Bug Summary

File:var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h
Warning:line 1725, column 7
Use of memory after it is freed

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name HeapSnapshot.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=all -relaxed-aliasing -ffp-contract=off -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/devtools/shared/heapsnapshot -fcoverage-compilation-dir=/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/devtools/shared/heapsnapshot -resource-dir /usr/lib/llvm-18/lib/clang/18 -include /var/lib/jenkins/workspace/firefox-scan-build/config/gcc_hidden.h -include /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/mozilla-config.h -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/stl_wrappers -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/system_wrappers -U _FORTIFY_SOURCE -D _FORTIFY_SOURCE=2 -D DEBUG=1 -D GOOGLE_PROTOBUF_NO_RTTI -D MOZ_HAS_MOZGLUE -D MOZILLA_INTERNAL_API -D IMPL_LIBXUL -D STATIC_EXPORTABLE_JS_API -I /var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/devtools/shared/heapsnapshot -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/ipc/ipdl/_ipdlheaders -I /var/lib/jenkins/workspace/firefox-scan-build/ipc/chromium/src -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/nspr -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/nss -D MOZILLA_CLIENT -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13 -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/x86_64-linux-gnu/c++/13 -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/backward -internal-isystem /usr/lib/llvm-18/lib/clang/18/include -internal-isystem /usr/local/include -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-error=tautological-type-limit-compare -Wno-invalid-offsetof -Wno-range-loop-analysis -Wno-deprecated-anon-enum-enum-conversion -Wno-deprecated-enum-enum-conversion -Wno-deprecated-this-capture -Wno-inline-new-delete -Wno-error=deprecated-declarations -Wno-error=array-bounds -Wno-error=free-nonheap-object -Wno-error=atomic-alignment -Wno-error=deprecated-builtins -Wno-psabi -Wno-error=builtin-macro-redefined -Wno-vla-cxx-extension -Wno-unknown-warning-option -fdeprecated-macro -ferror-limit 19 -stack-protector 2 -fstack-clash-protection -ftrivial-auto-var-init=pattern -fno-rtti -fgnuc-version=4.2.1 -fno-aligned-allocation -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2024-05-16-034744-15991-1 -x c++ /var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp

/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp

1/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
2/* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
5
6#include "HeapSnapshot.h"
7
8#include <google/protobuf/io/coded_stream.h>
9#include <google/protobuf/io/gzip_stream.h>
10#include <google/protobuf/io/zero_copy_stream_impl_lite.h>
11
12#include "js/Array.h" // JS::NewArrayObject
13#include "js/ColumnNumber.h" // JS::LimitedColumnNumberOneOrigin, JS::TaggedColumnNumberOneOrigin
14#include "js/Debug.h"
15#include "js/PropertyAndElement.h" // JS_DefineProperty
16#include "js/TypeDecls.h"
17#include "js/UbiNodeBreadthFirst.h"
18#include "js/UbiNodeCensus.h"
19#include "js/UbiNodeDominatorTree.h"
20#include "js/UbiNodeShortestPaths.h"
21#include "mozilla/Attributes.h"
22#include "mozilla/CycleCollectedJSContext.h"
23#include "mozilla/devtools/AutoMemMap.h"
24#include "mozilla/devtools/CoreDump.pb.h"
25#include "mozilla/devtools/DeserializedNode.h"
26#include "mozilla/devtools/DominatorTree.h"
27#include "mozilla/devtools/FileDescriptorOutputStream.h"
28#include "mozilla/devtools/HeapSnapshotTempFileHelperChild.h"
29#include "mozilla/devtools/ZeroCopyNSIOutputStream.h"
30#include "mozilla/dom/ChromeUtils.h"
31#include "mozilla/dom/ContentChild.h"
32#include "mozilla/dom/HeapSnapshotBinding.h"
33#include "mozilla/RangedPtr.h"
34#include "mozilla/Telemetry.h"
35#include "mozilla/Unused.h"
36
37#include "jsapi.h"
38#include "jsfriendapi.h"
39#include "js/GCVector.h"
40#include "js/MapAndSet.h"
41#include "js/Object.h" // JS::GetCompartment
42#include "nsComponentManagerUtils.h" // do_CreateInstance
43#include "nsCycleCollectionParticipant.h"
44#include "nsCRTGlue.h"
45#include "nsIFile.h"
46#include "nsIOutputStream.h"
47#include "nsISupportsImpl.h"
48#include "nsNetUtil.h"
49#include "nsPrintfCString.h"
50#include "prerror.h"
51#include "prio.h"
52#include "prtypes.h"
53#include "SpecialSystemDirectory.h"
54
55namespace mozilla {
56namespace devtools {
57
58using namespace JS;
59using namespace dom;
60
61using ::google::protobuf::io::ArrayInputStream;
62using ::google::protobuf::io::CodedInputStream;
63using ::google::protobuf::io::GzipInputStream;
64using ::google::protobuf::io::ZeroCopyInputStream;
65
66using JS::ubi::AtomOrTwoByteChars;
67using JS::ubi::ShortestPaths;
68
69MallocSizeOf GetCurrentThreadDebuggerMallocSizeOf() {
70 auto ccjscx = CycleCollectedJSContext::Get();
71 MOZ_ASSERT(ccjscx)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ccjscx)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(ccjscx))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("ccjscx", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 71); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ccjscx" ")");
do { *((volatile int*)__null) = 71; __attribute__((nomerge))
::abort(); } while (false); } } while (false)
;
72 auto cx = ccjscx->Context();
73 MOZ_ASSERT(cx)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(cx)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(cx))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("cx", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 73); AnnotateMozCrashReason("MOZ_ASSERT" "(" "cx" ")"); do {
*((volatile int*)__null) = 73; __attribute__((nomerge)) ::abort
(); } while (false); } } while (false)
;
74 auto mallocSizeOf = JS::dbg::GetDebuggerMallocSizeOf(cx);
75 MOZ_ASSERT(mallocSizeOf)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mallocSizeOf)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(mallocSizeOf))), 0))) { do {
} while (false); MOZ_ReportAssertionFailure("mallocSizeOf", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 75); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mallocSizeOf"
")"); do { *((volatile int*)__null) = 75; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
76 return mallocSizeOf;
77}
78
79/*** Cycle Collection Boilerplate *********************************************/
80
81NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(HeapSnapshot, mParent)static_assert(std::is_base_of<nsWrapperCache, HeapSnapshot
>::value, "Class should inherit nsWrapperCache"); HeapSnapshot
::cycleCollection HeapSnapshot::_cycleCollectorGlobal( nsCycleCollectionParticipant
::FlagMaybeSingleZoneJSHolder); void HeapSnapshot::cycleCollection
::Trace( void* p, const TraceCallbacks& aCallbacks, void*
aClosure) { HeapSnapshot* tmp = DowncastCCParticipant<HeapSnapshot
>(p); TraceWrapper(p, aCallbacks, aClosure); (void)tmp; } void
HeapSnapshot::cycleCollection::TraceWrapper( void* p, const TraceCallbacks
& aCallbacks, void* aClosure) { HeapSnapshot* tmp = DowncastCCParticipant
<HeapSnapshot>(p); tmp->TraceWrapper(aCallbacks, aClosure
); } void HeapSnapshot::cycleCollection::Unlink(void* p) { HeapSnapshot
* tmp = DowncastCCParticipant<HeapSnapshot>(p); ImplCycleCollectionUnlink
(tmp->mParent); tmp->ReleaseWrapper(p); (void)tmp; } nsresult
HeapSnapshot::cycleCollection::TraverseNative( void* p, nsCycleCollectionTraversalCallback
& cb) { HeapSnapshot* tmp = DowncastCCParticipant<HeapSnapshot
>(p); cb.DescribeRefCountedNode(tmp->mRefCnt.get(), "HeapSnapshot"
); ImplCycleCollectionTraverse(cb, tmp->mParent, "mParent"
, 0); (void)tmp; return NS_OK; }
82
83NS_IMPL_CYCLE_COLLECTING_ADDREF(HeapSnapshot)MozExternalRefCountType HeapSnapshot::AddRef(void) { static_assert
(!std::is_destructible_v<HeapSnapshot>, "Reference-counted class "
"HeapSnapshot" " should not have a public destructor. " "Make this class's destructor non-public"
); do { static_assert( mozilla::detail::AssertionConditionType
<decltype(int32_t(mRefCnt) >= 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(int32_t(mRefCnt) >= 0))),
0))) { do { } while (false); MOZ_ReportAssertionFailure("int32_t(mRefCnt) >= 0"
" (" "illegal refcnt" ")", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 83); AnnotateMozCrashReason("MOZ_ASSERT" "(" "int32_t(mRefCnt) >= 0"
") (" "illegal refcnt" ")"); do { *((volatile int*)__null) =
83; __attribute__((nomerge)) ::abort(); } while (false); } }
while (false); _mOwningThread.AssertOwnership("HeapSnapshot"
" not thread-safe"); nsISupports* base = HeapSnapshot::cycleCollection
::Upcast(this); nsrefcnt count = mRefCnt.incr(base); NS_LogAddRef
((this), (count), ("HeapSnapshot"), (uint32_t)(sizeof(*this))
); return count; }
84NS_IMPL_CYCLE_COLLECTING_RELEASE(HeapSnapshot)MozExternalRefCountType HeapSnapshot::Release(void) { do { static_assert
( mozilla::detail::AssertionConditionType<decltype(int32_t
(mRefCnt) > 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(int32_t(mRefCnt) > 0))), 0
))) { do { } while (false); MOZ_ReportAssertionFailure("int32_t(mRefCnt) > 0"
" (" "dup release" ")", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 84); AnnotateMozCrashReason("MOZ_ASSERT" "(" "int32_t(mRefCnt) > 0"
") (" "dup release" ")"); do { *((volatile int*)__null) = 84
; __attribute__((nomerge)) ::abort(); } while (false); } } while
(false); _mOwningThread.AssertOwnership("HeapSnapshot" " not thread-safe"
); nsISupports* base = HeapSnapshot::cycleCollection::Upcast(
this); nsrefcnt count = mRefCnt.decr(base); NS_LogRelease((this
), (count), ("HeapSnapshot")); return count; } void HeapSnapshot
::DeleteCycleCollectable(void) { delete (this); }
85
86NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(HeapSnapshot)nsresult HeapSnapshot::QueryInterface(const nsIID& aIID, void
** aInstancePtr) { do { if (!(aInstancePtr)) { NS_DebugBreak(
NS_DEBUG_ASSERTION, "QueryInterface requires a non-NULL destination!"
, "aInstancePtr", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 86); MOZ_PretendNoReturn(); } } while (0); nsISupports* foundInterface
; if (TopThreeWordsEquals( aIID, (nsXPCOMCycleCollectionParticipant
::COMTypeInfo<nsXPCOMCycleCollectionParticipant, void>::
kIID), (nsCycleCollectionISupports::COMTypeInfo<nsCycleCollectionISupports
, void>::kIID)) && (LowWordEquals(aIID, (nsXPCOMCycleCollectionParticipant
::COMTypeInfo<nsXPCOMCycleCollectionParticipant, void>::
kIID)) || LowWordEquals(aIID, (nsCycleCollectionISupports::COMTypeInfo
<nsCycleCollectionISupports, void>::kIID)))) { if (LowWordEquals
(aIID, (nsXPCOMCycleCollectionParticipant::COMTypeInfo<nsXPCOMCycleCollectionParticipant
, void>::kIID))) { *aInstancePtr = HeapSnapshot::cycleCollection
::GetParticipant(); return NS_OK; } if (LowWordEquals(aIID, (
nsCycleCollectionISupports::COMTypeInfo<nsCycleCollectionISupports
, void>::kIID))) { *aInstancePtr = HeapSnapshot::cycleCollection
::Upcast(this); return NS_OK; } foundInterface = nullptr; } else
87 NS_WRAPPERCACHE_INTERFACE_MAP_ENTRYif (aIID.Equals((nsWrapperCache::COMTypeInfo<nsWrapperCache
, void>::kIID))) { *aInstancePtr = static_cast<nsWrapperCache
*>(this); return NS_OK; } else
88 NS_INTERFACE_MAP_ENTRY(nsISupports)if (aIID.Equals(mozilla::detail::kImplementedIID<std::remove_reference_t
<decltype(*this)>, nsISupports>)) foundInterface = static_cast
<nsISupports*>(this); else
89NS_INTERFACE_MAP_ENDfoundInterface = 0; nsresult status; if (!foundInterface) { do
{ static_assert( mozilla::detail::AssertionConditionType<
decltype(!aIID.Equals((nsISupports::COMTypeInfo<nsISupports
, void>::kIID)))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!aIID.Equals((nsISupports::COMTypeInfo
<nsISupports, void>::kIID))))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("!aIID.Equals((nsISupports::COMTypeInfo<nsISupports, void>::kIID))"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 89); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!aIID.Equals((nsISupports::COMTypeInfo<nsISupports, void>::kIID))"
")"); do { *((volatile int*)__null) = 89; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false); status = NS_NOINTERFACE
; } else { (foundInterface)->AddRef(); status = NS_OK; } *
aInstancePtr = foundInterface; return status; }
90
91/* virtual */
92JSObject* HeapSnapshot::WrapObject(JSContext* aCx,
93 JS::Handle<JSObject*> aGivenProto) {
94 return HeapSnapshot_Binding::Wrap(aCx, this, aGivenProto);
95}
96
97/*** Reading Heap Snapshots ***************************************************/
98
99/* static */
100already_AddRefed<HeapSnapshot> HeapSnapshot::Create(JSContext* cx,
101 GlobalObject& global,
102 const uint8_t* buffer,
103 uint32_t size,
104 ErrorResult& rv) {
105 RefPtr<HeapSnapshot> snapshot = new HeapSnapshot(cx, global.GetAsSupports());
106 if (!snapshot->init(cx, buffer, size)) {
107 rv.Throw(NS_ERROR_UNEXPECTED);
108 return nullptr;
109 }
110 return snapshot.forget();
111}
112
113template <typename MessageType>
114static bool parseMessage(ZeroCopyInputStream& stream, uint32_t sizeOfMessage,
115 MessageType& message) {
116 // We need to create a new `CodedInputStream` for each message so that the
117 // 64MB limit is applied per-message rather than to the whole stream.
118 CodedInputStream codedStream(&stream);
119
120 // The protobuf message nesting that core dumps exhibit is dominated by
121 // allocation stacks' frames. In the most deeply nested case, each frame has
122 // two messages: a StackFrame message and a StackFrame::Data message. These
123 // frames are on top of a small constant of other messages. There are a
124 // MAX_STACK_DEPTH number of frames, so we multiply this by 3 to make room for
125 // the two messages per frame plus some head room for the constant number of
126 // non-dominating messages.
127 codedStream.SetRecursionLimit(HeapSnapshot::MAX_STACK_DEPTH * 3);
128
129 auto limit = codedStream.PushLimit(sizeOfMessage);
130 if (NS_WARN_IF(!message.ParseFromCodedStream(&codedStream))NS_warn_if_impl(!message.ParseFromCodedStream(&codedStream
), "!message.ParseFromCodedStream(&codedStream)", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 130)
||
131 NS_WARN_IF(!codedStream.ConsumedEntireMessage())NS_warn_if_impl(!codedStream.ConsumedEntireMessage(), "!codedStream.ConsumedEntireMessage()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 131)
||
132 NS_WARN_IF(codedStream.BytesUntilLimit() != 0)NS_warn_if_impl(codedStream.BytesUntilLimit() != 0, "codedStream.BytesUntilLimit() != 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 132)
) {
133 return false;
134 }
135
136 codedStream.PopLimit(limit);
137 return true;
138}
139
140template <typename CharT, typename InternedStringSet>
141struct GetOrInternStringMatcher {
142 InternedStringSet& internedStrings;
143
144 explicit GetOrInternStringMatcher(InternedStringSet& strings)
145 : internedStrings(strings) {}
146
147 const CharT* operator()(const std::string* str) {
148 MOZ_ASSERT(str)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(str)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(str))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("str", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 148); AnnotateMozCrashReason("MOZ_ASSERT" "(" "str" ")"); do
{ *((volatile int*)__null) = 148; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
149 size_t length = str->length() / sizeof(CharT);
150 auto tempString = reinterpret_cast<const CharT*>(str->data());
151
152 UniqueFreePtr<CharT[]> owned(NS_xstrndup(tempString, length));
153 if (!internedStrings.append(std::move(owned))) return nullptr;
154
155 return internedStrings.back().get();
156 }
157
158 const CharT* operator()(uint64_t ref) {
159 if (MOZ_LIKELY(ref < internedStrings.length())(__builtin_expect(!!(ref < internedStrings.length()), 1))) {
160 auto& string = internedStrings[ref];
161 MOZ_ASSERT(string)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(string)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(string))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("string", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 161); AnnotateMozCrashReason("MOZ_ASSERT" "(" "string" ")")
; do { *((volatile int*)__null) = 161; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
162 return string.get();
163 }
164
165 return nullptr;
166 }
167};
168
169template <
170 // Either char or char16_t.
171 typename CharT,
172 // A reference to either `internedOneByteStrings` or
173 // `internedTwoByteStrings` if CharT is char or char16_t respectively.
174 typename InternedStringSet>
175const CharT* HeapSnapshot::getOrInternString(
176 InternedStringSet& internedStrings, Maybe<StringOrRef>& maybeStrOrRef) {
177 // Incomplete message: has neither a string nor a reference to an already
178 // interned string.
179 if (MOZ_UNLIKELY(maybeStrOrRef.isNothing())(__builtin_expect(!!(maybeStrOrRef.isNothing()), 0))) return nullptr;
180
181 GetOrInternStringMatcher<CharT, InternedStringSet> m(internedStrings);
182 return maybeStrOrRef->match(m);
183}
184
185// Get a de-duplicated string as a Maybe<StringOrRef> from the given `msg`.
186#define GET_STRING_OR_REF_WITH_PROP_NAMES(msg, strPropertyName, \
187 refPropertyName) \
188 (msg.has_##refPropertyName() ? Some(StringOrRef(msg.refPropertyName())) \
189 : msg.has_##strPropertyName() ? Some(StringOrRef(&msg.strPropertyName())) \
190 : Nothing())
191
192#define GET_STRING_OR_REF(msg, property) \
193 (msg.has_##property##ref() ? Some(StringOrRef(msg.property##ref())) \
194 : msg.has_##property() ? Some(StringOrRef(&msg.property())) \
195 : Nothing())
196
197bool HeapSnapshot::saveNode(const protobuf::Node& node,
198 NodeIdSet& edgeReferents) {
199 // NB: de-duplicated string properties must be read back and interned in the
200 // same order here as they are written and serialized in
201 // `CoreDumpWriter::writeNode` or else indices in references to already
202 // serialized strings will be off.
203
204 if (NS_WARN_IF(!node.has_id())NS_warn_if_impl(!node.has_id(), "!node.has_id()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 204)
) return false;
205 NodeId id = node.id();
206
207 // NodeIds are derived from pointers (at most 48 bits) and we rely on them
208 // fitting into JS numbers (IEEE 754 doubles, can precisely store 53 bit
209 // integers) despite storing them on disk as 64 bit integers.
210 if (NS_WARN_IF(!JS::Value::isNumberRepresentable(id))NS_warn_if_impl(!JS::Value::isNumberRepresentable(id), "!JS::Value::isNumberRepresentable(id)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 210)
) return false;
211
212 // Should only deserialize each node once.
213 if (NS_WARN_IF(nodes.has(id))NS_warn_if_impl(nodes.has(id), "nodes.has(id)", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 213)
) return false;
214
215 if (NS_WARN_IF(!JS::ubi::Uint32IsValidCoarseType(node.coarsetype()))NS_warn_if_impl(!JS::ubi::Uint32IsValidCoarseType(node.coarsetype
()), "!JS::ubi::Uint32IsValidCoarseType(node.coarsetype())", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 215)
)
216 return false;
217 auto coarseType = JS::ubi::Uint32ToCoarseType(node.coarsetype());
218
219 Maybe<StringOrRef> typeNameOrRef =
220 GET_STRING_OR_REF_WITH_PROP_NAMES(node, typename_, typenameref);
221 auto typeName =
222 getOrInternString<char16_t>(internedTwoByteStrings, typeNameOrRef);
223 if (NS_WARN_IF(!typeName)NS_warn_if_impl(!typeName, "!typeName", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 223)
) return false;
224
225 if (NS_WARN_IF(!node.has_size())NS_warn_if_impl(!node.has_size(), "!node.has_size()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 225)
) return false;
226 uint64_t size = node.size();
227
228 auto edgesLength = node.edges_size();
229 DeserializedNode::EdgeVector edges;
230 if (NS_WARN_IF(!edges.reserve(edgesLength))NS_warn_if_impl(!edges.reserve(edgesLength), "!edges.reserve(edgesLength)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 230)
) return false;
231 for (decltype(edgesLength) i = 0; i < edgesLength; i++) {
232 auto& protoEdge = node.edges(i);
233
234 if (NS_WARN_IF(!protoEdge.has_referent())NS_warn_if_impl(!protoEdge.has_referent(), "!protoEdge.has_referent()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 234)
) return false;
235 NodeId referent = protoEdge.referent();
236
237 if (NS_WARN_IF(!edgeReferents.put(referent))NS_warn_if_impl(!edgeReferents.put(referent), "!edgeReferents.put(referent)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 237)
) return false;
238
239 const char16_t* edgeName = nullptr;
240 if (protoEdge.EdgeNameOrRef_case() !=
241 protobuf::Edge::EDGENAMEORREF_NOT_SET) {
242 Maybe<StringOrRef> edgeNameOrRef = GET_STRING_OR_REF(protoEdge, name);
243 edgeName =
244 getOrInternString<char16_t>(internedTwoByteStrings, edgeNameOrRef);
245 if (NS_WARN_IF(!edgeName)NS_warn_if_impl(!edgeName, "!edgeName", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 245)
) return false;
246 }
247
248 edges.infallibleAppend(DeserializedEdge(referent, edgeName));
249 }
250
251 Maybe<StackFrameId> allocationStack;
252 if (node.has_allocationstack()) {
253 StackFrameId id = 0;
254 if (NS_WARN_IF(!saveStackFrame(node.allocationstack(), id))NS_warn_if_impl(!saveStackFrame(node.allocationstack(), id), "!saveStackFrame(node.allocationstack(), id)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 254)
) return false;
255 allocationStack.emplace(id);
256 }
257 MOZ_ASSERT(allocationStack.isSome() == node.has_allocationstack())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(allocationStack.isSome() == node.has_allocationstack
())>::isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!(allocationStack.isSome() == node.has_allocationstack
()))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("allocationStack.isSome() == node.has_allocationstack()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 257); AnnotateMozCrashReason("MOZ_ASSERT" "(" "allocationStack.isSome() == node.has_allocationstack()"
")"); do { *((volatile int*)__null) = 257; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
258
259 const char* jsObjectClassName = nullptr;
260 if (node.JSObjectClassNameOrRef_case() !=
261 protobuf::Node::JSOBJECTCLASSNAMEORREF_NOT_SET) {
262 Maybe<StringOrRef> clsNameOrRef =
263 GET_STRING_OR_REF(node, jsobjectclassname);
264 jsObjectClassName =
265 getOrInternString<char>(internedOneByteStrings, clsNameOrRef);
266 if (NS_WARN_IF(!jsObjectClassName)NS_warn_if_impl(!jsObjectClassName, "!jsObjectClassName", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 266)
) return false;
267 }
268
269 const char* scriptFilename = nullptr;
270 if (node.ScriptFilenameOrRef_case() !=
271 protobuf::Node::SCRIPTFILENAMEORREF_NOT_SET) {
272 Maybe<StringOrRef> scriptFilenameOrRef =
273 GET_STRING_OR_REF(node, scriptfilename);
274 scriptFilename =
275 getOrInternString<char>(internedOneByteStrings, scriptFilenameOrRef);
276 if (NS_WARN_IF(!scriptFilename)NS_warn_if_impl(!scriptFilename, "!scriptFilename", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 276)
) return false;
277 }
278
279 const char16_t* descriptiveTypeName = nullptr;
280 if (node.descriptiveTypeNameOrRef_case() !=
281 protobuf::Node::DESCRIPTIVETYPENAMEORREF_NOT_SET) {
282 Maybe<StringOrRef> descriptiveTypeNameOrRef =
283 GET_STRING_OR_REF(node, descriptivetypename);
284 descriptiveTypeName = getOrInternString<char16_t>(internedTwoByteStrings,
285 descriptiveTypeNameOrRef);
286 if (NS_WARN_IF(!descriptiveTypeName)NS_warn_if_impl(!descriptiveTypeName, "!descriptiveTypeName",
"/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 286)
) return false;
287 }
288
289 if (NS_WARN_IF(!nodes.putNew(NS_warn_if_impl(!nodes.putNew( id, DeserializedNode(id, coarseType
, typeName, size, std::move(edges), allocationStack, jsObjectClassName
, scriptFilename, descriptiveTypeName, *this)), "!nodes.putNew( id, DeserializedNode(id, coarseType, typeName, size, std::move(edges), allocationStack, jsObjectClassName, scriptFilename, descriptiveTypeName, *this))"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 292)
290 id, DeserializedNode(id, coarseType, typeName, size, std::move(edges),NS_warn_if_impl(!nodes.putNew( id, DeserializedNode(id, coarseType
, typeName, size, std::move(edges), allocationStack, jsObjectClassName
, scriptFilename, descriptiveTypeName, *this)), "!nodes.putNew( id, DeserializedNode(id, coarseType, typeName, size, std::move(edges), allocationStack, jsObjectClassName, scriptFilename, descriptiveTypeName, *this))"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 292)
291 allocationStack, jsObjectClassName,NS_warn_if_impl(!nodes.putNew( id, DeserializedNode(id, coarseType
, typeName, size, std::move(edges), allocationStack, jsObjectClassName
, scriptFilename, descriptiveTypeName, *this)), "!nodes.putNew( id, DeserializedNode(id, coarseType, typeName, size, std::move(edges), allocationStack, jsObjectClassName, scriptFilename, descriptiveTypeName, *this))"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 292)
292 scriptFilename, descriptiveTypeName, *this)))NS_warn_if_impl(!nodes.putNew( id, DeserializedNode(id, coarseType
, typeName, size, std::move(edges), allocationStack, jsObjectClassName
, scriptFilename, descriptiveTypeName, *this)), "!nodes.putNew( id, DeserializedNode(id, coarseType, typeName, size, std::move(edges), allocationStack, jsObjectClassName, scriptFilename, descriptiveTypeName, *this))"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 292)
) {
293 return false;
294 };
295
296 return true;
297}
298
299bool HeapSnapshot::saveStackFrame(const protobuf::StackFrame& frame,
300 StackFrameId& outFrameId) {
301 // NB: de-duplicated string properties must be read in the same order here as
302 // they are written in `CoreDumpWriter::getProtobufStackFrame` or else indices
303 // in references to already serialized strings will be off.
304
305 if (frame.has_ref()) {
306 // We should only get a reference to the previous frame if we have already
307 // seen the previous frame.
308 if (!frames.has(frame.ref())) return false;
309
310 outFrameId = frame.ref();
311 return true;
312 }
313
314 // Incomplete message.
315 if (!frame.has_data()) return false;
316
317 auto data = frame.data();
318
319 if (!data.has_id()) return false;
320 StackFrameId id = data.id();
321
322 // This should be the first and only time we see this frame.
323 if (frames.has(id)) return false;
324
325 if (!data.has_line()) return false;
326 uint32_t line = data.line();
327
328 if (!data.has_column()) return false;
329 JS::TaggedColumnNumberOneOrigin column(
330 JS::LimitedColumnNumberOneOrigin(data.column()));
331
332 if (!data.has_issystem()) return false;
333 bool isSystem = data.issystem();
334
335 if (!data.has_isselfhosted()) return false;
336 bool isSelfHosted = data.isselfhosted();
337
338 Maybe<StringOrRef> sourceOrRef = GET_STRING_OR_REF(data, source);
339 auto source =
340 getOrInternString<char16_t>(internedTwoByteStrings, sourceOrRef);
341 if (!source) return false;
342
343 const char16_t* functionDisplayName = nullptr;
344 if (data.FunctionDisplayNameOrRef_case() !=
345 protobuf::StackFrame_Data::FUNCTIONDISPLAYNAMEORREF_NOT_SET) {
346 Maybe<StringOrRef> nameOrRef = GET_STRING_OR_REF(data, functiondisplayname);
347 functionDisplayName =
348 getOrInternString<char16_t>(internedTwoByteStrings, nameOrRef);
349 if (!functionDisplayName) return false;
350 }
351
352 Maybe<StackFrameId> parent;
353 if (data.has_parent()) {
354 StackFrameId parentId = 0;
355 if (!saveStackFrame(data.parent(), parentId)) return false;
356 parent = Some(parentId);
357 }
358
359 if (!frames.putNew(id,
360 DeserializedStackFrame(id, parent, line, column, source,
361 functionDisplayName, isSystem,
362 isSelfHosted, *this))) {
363 return false;
364 }
365
366 outFrameId = id;
367 return true;
368}
369
370#undef GET_STRING_OR_REF_WITH_PROP_NAMES
371#undef GET_STRING_OR_REF
372
373// Because protobuf messages aren't self-delimiting, we serialize each message
374// preceded by its size in bytes. When deserializing, we read this size and then
375// limit reading from the stream to the given byte size. If we didn't, then the
376// first message would consume the entire stream.
377static bool readSizeOfNextMessage(ZeroCopyInputStream& stream,
378 uint32_t* sizep) {
379 MOZ_ASSERT(sizep)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(sizep)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(sizep))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("sizep", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 379); AnnotateMozCrashReason("MOZ_ASSERT" "(" "sizep" ")");
do { *((volatile int*)__null) = 379; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false)
;
380 CodedInputStream codedStream(&stream);
381 return codedStream.ReadVarint32(sizep) && *sizep > 0;
382}
383
384bool HeapSnapshot::init(JSContext* cx, const uint8_t* buffer, uint32_t size) {
385 ArrayInputStream stream(buffer, size);
386 GzipInputStream gzipStream(&stream);
387 uint32_t sizeOfMessage = 0;
388
389 // First is the metadata.
390
391 protobuf::Metadata metadata;
392 if (NS_WARN_IF(!readSizeOfNextMessage(gzipStream, &sizeOfMessage))NS_warn_if_impl(!readSizeOfNextMessage(gzipStream, &sizeOfMessage
), "!readSizeOfNextMessage(gzipStream, &sizeOfMessage)", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 392)
)
393 return false;
394 if (!parseMessage(gzipStream, sizeOfMessage, metadata)) return false;
395 if (metadata.has_timestamp()) timestamp.emplace(metadata.timestamp());
396
397 // Next is the root node.
398
399 protobuf::Node root;
400 if (NS_WARN_IF(!readSizeOfNextMessage(gzipStream, &sizeOfMessage))NS_warn_if_impl(!readSizeOfNextMessage(gzipStream, &sizeOfMessage
), "!readSizeOfNextMessage(gzipStream, &sizeOfMessage)", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 400)
)
401 return false;
402 if (!parseMessage(gzipStream, sizeOfMessage, root)) return false;
403
404 // Although the id is optional in the protobuf format for future proofing, we
405 // can't currently do anything without it.
406 if (NS_WARN_IF(!root.has_id())NS_warn_if_impl(!root.has_id(), "!root.has_id()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 406)
) return false;
407 rootId = root.id();
408
409 // The set of all node ids we've found edges pointing to.
410 NodeIdSet edgeReferents(cx);
411
412 if (NS_WARN_IF(!saveNode(root, edgeReferents))NS_warn_if_impl(!saveNode(root, edgeReferents), "!saveNode(root, edgeReferents)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 412)
) return false;
413
414 // Finally, the rest of the nodes in the core dump.
415
416 // Test for the end of the stream. The protobuf library gives no way to tell
417 // the difference between an underlying read error and the stream being
418 // done. All we can do is attempt to read the size of the next message and
419 // extrapolate guestimations from the result of that operation.
420 while (readSizeOfNextMessage(gzipStream, &sizeOfMessage)) {
421 protobuf::Node node;
422 if (!parseMessage(gzipStream, sizeOfMessage, node)) return false;
423 if (NS_WARN_IF(!saveNode(node, edgeReferents))NS_warn_if_impl(!saveNode(node, edgeReferents), "!saveNode(node, edgeReferents)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 423)
) return false;
424 }
425
426 // Check the set of node ids referred to by edges we found and ensure that we
427 // have the node corresponding to each id. If we don't have all of them, it is
428 // unsafe to perform analyses of this heap snapshot.
429 for (auto iter = edgeReferents.iter(); !iter.done(); iter.next()) {
430 if (NS_WARN_IF(!nodes.has(iter.get()))NS_warn_if_impl(!nodes.has(iter.get()), "!nodes.has(iter.get())"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 430)
) return false;
431 }
432
433 return true;
434}
435
436/*** Heap Snapshot Analyses ***************************************************/
437
438void HeapSnapshot::TakeCensus(JSContext* cx, JS::Handle<JSObject*> options,
439 JS::MutableHandle<JS::Value> rval,
440 ErrorResult& rv) {
441 JS::ubi::Census census(cx);
442
443 JS::ubi::CountTypePtr rootType;
444 if (NS_WARN_IF(!JS::ubi::ParseCensusOptions(cx, census, options, rootType))NS_warn_if_impl(!JS::ubi::ParseCensusOptions(cx, census, options
, rootType), "!JS::ubi::ParseCensusOptions(cx, census, options, rootType)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 444)
) {
445 rv.Throw(NS_ERROR_UNEXPECTED);
446 return;
447 }
448
449 JS::ubi::RootedCount rootCount(cx, rootType->makeCount());
450 if (NS_WARN_IF(!rootCount)NS_warn_if_impl(!rootCount, "!rootCount", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 450)
) {
451 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
452 return;
453 }
454
455 JS::ubi::CensusHandler handler(census, rootCount,
456 GetCurrentThreadDebuggerMallocSizeOf());
457
458 {
459 JS::AutoCheckCannotGC nogc;
460
461 JS::ubi::CensusTraversal traversal(cx, handler, nogc);
462
463 if (NS_WARN_IF(!traversal.addStart(getRoot()))NS_warn_if_impl(!traversal.addStart(getRoot()), "!traversal.addStart(getRoot())"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 463)
) {
464 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
465 return;
466 }
467
468 if (NS_WARN_IF(!traversal.traverse())NS_warn_if_impl(!traversal.traverse(), "!traversal.traverse()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 468)
) {
469 rv.Throw(NS_ERROR_UNEXPECTED);
470 return;
471 }
472 }
473
474 if (NS_WARN_IF(!handler.report(cx, rval))NS_warn_if_impl(!handler.report(cx, rval), "!handler.report(cx, rval)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 474)
) {
475 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
476 return;
477 }
478}
479
480void HeapSnapshot::DescribeNode(JSContext* cx, JS::Handle<JSObject*> breakdown,
481 uint64_t nodeId,
482 JS::MutableHandle<JS::Value> rval,
483 ErrorResult& rv) {
484 MOZ_ASSERT(breakdown)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(breakdown)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(breakdown))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("breakdown", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 484); AnnotateMozCrashReason("MOZ_ASSERT" "(" "breakdown" ")"
); do { *((volatile int*)__null) = 484; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
485 JS::Rooted<JS::Value> breakdownVal(cx, JS::ObjectValue(*breakdown));
486 JS::Rooted<JS::GCVector<JSLinearString*>> seen(cx, cx);
487 JS::ubi::CountTypePtr rootType =
488 JS::ubi::ParseBreakdown(cx, breakdownVal, &seen);
489 if (NS_WARN_IF(!rootType)NS_warn_if_impl(!rootType, "!rootType", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 489)
) {
490 rv.Throw(NS_ERROR_UNEXPECTED);
491 return;
492 }
493
494 JS::ubi::RootedCount rootCount(cx, rootType->makeCount());
495 if (NS_WARN_IF(!rootCount)NS_warn_if_impl(!rootCount, "!rootCount", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 495)
) {
496 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
497 return;
498 }
499
500 JS::ubi::Node::Id id(nodeId);
501 Maybe<JS::ubi::Node> node = getNodeById(id);
502 if (NS_WARN_IF(node.isNothing())NS_warn_if_impl(node.isNothing(), "node.isNothing()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 502)
) {
503 rv.Throw(NS_ERROR_INVALID_ARG);
504 return;
505 }
506
507 MallocSizeOf mallocSizeOf = GetCurrentThreadDebuggerMallocSizeOf();
508 if (NS_WARN_IF(!rootCount->count(mallocSizeOf, *node))NS_warn_if_impl(!rootCount->count(mallocSizeOf, *node), "!rootCount->count(mallocSizeOf, *node)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 508)
) {
509 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
510 return;
511 }
512
513 if (NS_WARN_IF(!rootCount->report(cx, rval))NS_warn_if_impl(!rootCount->report(cx, rval), "!rootCount->report(cx, rval)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 513)
) {
514 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
515 return;
516 }
517}
518
519already_AddRefed<DominatorTree> HeapSnapshot::ComputeDominatorTree(
520 ErrorResult& rv) {
521 Maybe<JS::ubi::DominatorTree> maybeTree;
522 {
523 auto ccjscx = CycleCollectedJSContext::Get();
524 MOZ_ASSERT(ccjscx)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ccjscx)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(ccjscx))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("ccjscx", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 524); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ccjscx" ")")
; do { *((volatile int*)__null) = 524; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
525 auto cx = ccjscx->Context();
526 MOZ_ASSERT(cx)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(cx)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(cx))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("cx", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 526); AnnotateMozCrashReason("MOZ_ASSERT" "(" "cx" ")"); do
{ *((volatile int*)__null) = 526; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
527 JS::AutoCheckCannotGC nogc(cx);
528 maybeTree = JS::ubi::DominatorTree::Create(cx, nogc, getRoot());
529 }
530
531 if (NS_WARN_IF(maybeTree.isNothing())NS_warn_if_impl(maybeTree.isNothing(), "maybeTree.isNothing()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 531)
) {
532 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
533 return nullptr;
534 }
535
536 return MakeAndAddRef<DominatorTree>(std::move(*maybeTree), this, mParent);
537}
538
539void HeapSnapshot::ComputeShortestPaths(JSContext* cx, uint64_t start,
540 const Sequence<uint64_t>& targets,
541 uint64_t maxNumPaths,
542 JS::MutableHandle<JSObject*> results,
543 ErrorResult& rv) {
544 // First ensure that our inputs are valid.
545
546 if (NS_WARN_IF(maxNumPaths == 0)NS_warn_if_impl(maxNumPaths == 0, "maxNumPaths == 0", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 546)
) {
1
Assuming 'maxNumPaths' is not equal to 0
2
Taking false branch
547 rv.Throw(NS_ERROR_INVALID_ARG);
548 return;
549 }
550
551 Maybe<JS::ubi::Node> startNode = getNodeById(start);
552 if (NS_WARN_IF(startNode.isNothing())NS_warn_if_impl(startNode.isNothing(), "startNode.isNothing()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 552)
) {
3
Taking false branch
553 rv.Throw(NS_ERROR_INVALID_ARG);
554 return;
555 }
556
557 if (NS_WARN_IF(targets.Length() == 0)NS_warn_if_impl(targets.Length() == 0, "targets.Length() == 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 557)
) {
4
Assuming the condition is false
5
Taking false branch
558 rv.Throw(NS_ERROR_INVALID_ARG);
559 return;
560 }
561
562 // Aggregate the targets into a set and make sure that they exist in the heap
563 // snapshot.
564
565 JS::ubi::NodeSet targetsSet;
566
567 for (const auto& target : targets) {
568 Maybe<JS::ubi::Node> targetNode = getNodeById(target);
569 if (NS_WARN_IF(targetNode.isNothing())NS_warn_if_impl(targetNode.isNothing(), "targetNode.isNothing()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 569)
) {
6
Taking false branch
570 rv.Throw(NS_ERROR_INVALID_ARG);
571 return;
572 }
573
574 if (NS_WARN_IF(!targetsSet.put(*targetNode))NS_warn_if_impl(!targetsSet.put(*targetNode), "!targetsSet.put(*targetNode)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 574)
) {
7
Assuming the condition is false
8
Taking false branch
575 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
576 return;
577 }
578 }
579
580 // Walk the heap graph and find the shortest paths.
581
582 Maybe<ShortestPaths> maybeShortestPaths;
583 {
584 JS::AutoCheckCannotGC nogc(cx);
585 maybeShortestPaths = ShortestPaths::Create(
586 cx, nogc, maxNumPaths, *startNode, std::move(targetsSet));
587 }
588
589 if (NS_WARN_IF(maybeShortestPaths.isNothing())NS_warn_if_impl(maybeShortestPaths.isNothing(), "maybeShortestPaths.isNothing()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 589)
) {
9
Taking false branch
590 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
591 return;
592 }
593
594 auto& shortestPaths = *maybeShortestPaths;
595
596 // Convert the results into a Map object mapping target node IDs to arrays of
597 // paths found.
598
599 JS::Rooted<JSObject*> resultsMap(cx, JS::NewMapObject(cx));
600 if (NS_WARN_IF(!resultsMap)NS_warn_if_impl(!resultsMap, "!resultsMap", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 600)
) {
10
Taking true branch
601 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
602 return;
11
Calling implicit destructor for 'Maybe<JS::ubi::ShortestPaths>'
12
Calling '~MaybeStorage'
603 }
604
605 for (auto iter = shortestPaths.targetIter(); !iter.done(); iter.next()) {
606 JS::Rooted<JS::Value> key(cx, JS::NumberValue(iter.get().identifier()));
607 JS::RootedVector<JS::Value> paths(cx);
608
609 bool ok = shortestPaths.forEachPath(iter.get(), [&](JS::ubi::Path& path) {
610 JS::RootedVector<JS::Value> pathValues(cx);
611
612 for (JS::ubi::BackEdge* edge : path) {
613 JS::Rooted<JSObject*> pathPart(cx, JS_NewPlainObject(cx));
614 if (!pathPart) {
615 return false;
616 }
617
618 JS::Rooted<JS::Value> predecessor(
619 cx, NumberValue(edge->predecessor().identifier()));
620 if (!JS_DefineProperty(cx, pathPart, "predecessor", predecessor,
621 JSPROP_ENUMERATE)) {
622 return false;
623 }
624
625 JS::Rooted<JS::Value> edgeNameVal(cx, NullValue());
626 if (edge->name()) {
627 JS::Rooted<JSString*> edgeName(
628 cx, JS_AtomizeUCString(cx, edge->name().get()));
629 if (!edgeName) {
630 return false;
631 }
632 edgeNameVal = StringValue(edgeName);
633 }
634
635 if (!JS_DefineProperty(cx, pathPart, "edge", edgeNameVal,
636 JSPROP_ENUMERATE)) {
637 return false;
638 }
639
640 if (!pathValues.append(ObjectValue(*pathPart))) {
641 return false;
642 }
643 }
644
645 JS::Rooted<JSObject*> pathObj(cx, JS::NewArrayObject(cx, pathValues));
646 return pathObj && paths.append(ObjectValue(*pathObj));
647 });
648
649 if (NS_WARN_IF(!ok)NS_warn_if_impl(!ok, "!ok", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 649)
) {
650 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
651 return;
652 }
653
654 JS::Rooted<JSObject*> pathsArray(cx, JS::NewArrayObject(cx, paths));
655 if (NS_WARN_IF(!pathsArray)NS_warn_if_impl(!pathsArray, "!pathsArray", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 655)
) {
656 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
657 return;
658 }
659
660 JS::Rooted<JS::Value> pathsVal(cx, ObjectValue(*pathsArray));
661 if (NS_WARN_IF(!JS::MapSet(cx, resultsMap, key, pathsVal))NS_warn_if_impl(!JS::MapSet(cx, resultsMap, key, pathsVal), "!JS::MapSet(cx, resultsMap, key, pathsVal)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 661)
) {
662 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
663 return;
664 }
665 }
666
667 results.set(resultsMap);
668}
669
670/*** Saving Heap Snapshots ****************************************************/
671
672// If we are only taking a snapshot of the heap affected by the given set of
673// globals, find the set of compartments the globals are allocated
674// within. Returns false on OOM failure.
675static bool PopulateCompartmentsWithGlobals(
676 CompartmentSet& compartments, JS::HandleVector<JSObject*> globals) {
677 unsigned length = globals.length();
678 for (unsigned i = 0; i < length; i++) {
679 if (!compartments.put(JS::GetCompartment(globals[i]))) return false;
680 }
681
682 return true;
683}
684
685// Add the given set of globals as explicit roots in the given roots
686// list. Returns false on OOM failure.
687static bool AddGlobalsAsRoots(JS::HandleVector<JSObject*> globals,
688 ubi::RootList& roots) {
689 unsigned length = globals.length();
690 for (unsigned i = 0; i < length; i++) {
691 if (!roots.addRoot(ubi::Node(globals[i].get()), u"heap snapshot global")) {
692 return false;
693 }
694 }
695 return true;
696}
697
698// Choose roots and limits for a traversal, given `boundaries`. Set `roots` to
699// the set of nodes within the boundaries that are referred to by nodes
700// outside. If `boundaries` does not include all JS compartments, initialize
701// `compartments` to the set of included compartments; otherwise, leave
702// `compartments` uninitialized. (You can use compartments.initialized() to
703// check.)
704//
705// If `boundaries` is incoherent, or we encounter an error while trying to
706// handle it, or we run out of memory, set `rv` appropriately and return
707// `false`.
708//
709// Return value is a pair of the status and an AutoCheckCannotGC token,
710// forwarded from ubi::RootList::init(), to ensure that the caller does
711// not GC while the RootList is live and initialized.
712static std::pair<bool, AutoCheckCannotGC> EstablishBoundaries(
713 JSContext* cx, ErrorResult& rv, const HeapSnapshotBoundaries& boundaries,
714 ubi::RootList& roots, CompartmentSet& compartments) {
715 MOZ_ASSERT(!roots.initialized())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!roots.initialized())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!roots.initialized()))), 0))
) { do { } while (false); MOZ_ReportAssertionFailure("!roots.initialized()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 715); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!roots.initialized()"
")"); do { *((volatile int*)__null) = 715; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
716 MOZ_ASSERT(compartments.empty())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(compartments.empty())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(compartments.empty()))), 0))
) { do { } while (false); MOZ_ReportAssertionFailure("compartments.empty()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 716); AnnotateMozCrashReason("MOZ_ASSERT" "(" "compartments.empty()"
")"); do { *((volatile int*)__null) = 716; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
717
718 bool foundBoundaryProperty = false;
719
720 if (boundaries.mRuntime.WasPassed()) {
721 foundBoundaryProperty = true;
722
723 if (!boundaries.mRuntime.Value()) {
724 rv.Throw(NS_ERROR_INVALID_ARG);
725 return {false, AutoCheckCannotGC(cx)};
726 }
727
728 auto [ok, nogc] = roots.init();
729 if (!ok) {
730 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
731 return {false, nogc};
732 }
733 }
734
735 if (boundaries.mDebugger.WasPassed()) {
736 if (foundBoundaryProperty) {
737 rv.Throw(NS_ERROR_INVALID_ARG);
738 return {false, AutoCheckCannotGC(cx)};
739 }
740 foundBoundaryProperty = true;
741
742 JSObject* dbgObj = boundaries.mDebugger.Value();
743 if (!dbgObj || !dbg::IsDebugger(*dbgObj)) {
744 rv.Throw(NS_ERROR_INVALID_ARG);
745 return {false, AutoCheckCannotGC(cx)};
746 }
747
748 JS::RootedVector<JSObject*> globals(cx);
749 if (!dbg::GetDebuggeeGlobals(cx, *dbgObj, &globals) ||
750 !PopulateCompartmentsWithGlobals(compartments, globals) ||
751 !roots.init(compartments).first || !AddGlobalsAsRoots(globals, roots)) {
752 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
753 return {false, AutoCheckCannotGC(cx)};
754 }
755 }
756
757 if (boundaries.mGlobals.WasPassed()) {
758 if (foundBoundaryProperty) {
759 rv.Throw(NS_ERROR_INVALID_ARG);
760 return {false, AutoCheckCannotGC(cx)};
761 }
762 foundBoundaryProperty = true;
763
764 uint32_t length = boundaries.mGlobals.Value().Length();
765 if (length == 0) {
766 rv.Throw(NS_ERROR_INVALID_ARG);
767 return {false, AutoCheckCannotGC(cx)};
768 }
769
770 JS::RootedVector<JSObject*> globals(cx);
771 for (uint32_t i = 0; i < length; i++) {
772 JSObject* global = boundaries.mGlobals.Value().ElementAt(i);
773 if (!JS_IsGlobalObject(global)) {
774 rv.Throw(NS_ERROR_INVALID_ARG);
775 return {false, AutoCheckCannotGC(cx)};
776 }
777 if (!globals.append(global)) {
778 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
779 return {false, AutoCheckCannotGC(cx)};
780 }
781 }
782
783 if (!PopulateCompartmentsWithGlobals(compartments, globals) ||
784 !roots.init(compartments).first || !AddGlobalsAsRoots(globals, roots)) {
785 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
786 return {false, AutoCheckCannotGC(cx)};
787 }
788 }
789 AutoCheckCannotGC nogc(cx);
790
791 if (!foundBoundaryProperty) {
792 rv.Throw(NS_ERROR_INVALID_ARG);
793 return {false, nogc};
794 }
795
796 MOZ_ASSERT(roots.initialized())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(roots.initialized())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(roots.initialized()))), 0)))
{ do { } while (false); MOZ_ReportAssertionFailure("roots.initialized()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 796); AnnotateMozCrashReason("MOZ_ASSERT" "(" "roots.initialized()"
")"); do { *((volatile int*)__null) = 796; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
797 return {true, nogc};
798}
799
800// A variant covering all the various two-byte strings that we can get from the
801// ubi::Node API.
802class TwoByteString
803 : public Variant<JSAtom*, const char16_t*, JS::ubi::EdgeName> {
804 using Base = Variant<JSAtom*, const char16_t*, JS::ubi::EdgeName>;
805
806 struct CopyToBufferMatcher {
807 RangedPtr<char16_t> destination;
808 size_t maxLength;
809
810 CopyToBufferMatcher(RangedPtr<char16_t> destination, size_t maxLength)
811 : destination(destination), maxLength(maxLength) {}
812
813 size_t operator()(JS::ubi::EdgeName& ptr) {
814 return ptr ? operator()(ptr.get()) : 0;
815 }
816
817 size_t operator()(JSAtom* atom) {
818 MOZ_ASSERT(atom)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(atom)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(atom))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("atom", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 818); AnnotateMozCrashReason("MOZ_ASSERT" "(" "atom" ")"); do
{ *((volatile int*)__null) = 818; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
819 JS::ubi::AtomOrTwoByteChars s(atom);
820 return s.copyToBuffer(destination, maxLength);
821 }
822
823 size_t operator()(const char16_t* chars) {
824 MOZ_ASSERT(chars)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(chars)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(chars))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("chars", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 824); AnnotateMozCrashReason("MOZ_ASSERT" "(" "chars" ")");
do { *((volatile int*)__null) = 824; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false)
;
825 JS::ubi::AtomOrTwoByteChars s(chars);
826 return s.copyToBuffer(destination, maxLength);
827 }
828 };
829
830 public:
831 template <typename T>
832 MOZ_IMPLICIT TwoByteString(T&& rhs) : Base(std::forward<T>(rhs)) {}
833
834 template <typename T>
835 TwoByteString& operator=(T&& rhs) {
836 MOZ_ASSERT(this != &rhs, "self-move disallowed")do { static_assert( mozilla::detail::AssertionConditionType<
decltype(this != &rhs)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(this != &rhs))), 0))) { do
{ } while (false); MOZ_ReportAssertionFailure("this != &rhs"
" (" "self-move disallowed" ")", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 836); AnnotateMozCrashReason("MOZ_ASSERT" "(" "this != &rhs"
") (" "self-move disallowed" ")"); do { *((volatile int*)__null
) = 836; __attribute__((nomerge)) ::abort(); } while (false);
} } while (false)
;
837 this->~TwoByteString();
838 new (this) TwoByteString(std::forward<T>(rhs));
839 return *this;
840 }
841
842 TwoByteString(const TwoByteString&) = delete;
843 TwoByteString& operator=(const TwoByteString&) = delete;
844
845 // Rewrap the inner value of a JS::ubi::AtomOrTwoByteChars as a TwoByteString.
846 static TwoByteString from(JS::ubi::AtomOrTwoByteChars&& s) {
847 return s.match([](auto* a) { return TwoByteString(a); });
848 }
849
850 // Returns true if the given TwoByteString is non-null, false otherwise.
851 bool isNonNull() const {
852 return match([](auto& t) { return t != nullptr; });
853 }
854
855 // Return the length of the string, 0 if it is null.
856 size_t length() const {
857 return match(
858 [](JSAtom* atom) -> size_t {
859 MOZ_ASSERT(atom)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(atom)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(atom))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("atom", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 859); AnnotateMozCrashReason("MOZ_ASSERT" "(" "atom" ")"); do
{ *((volatile int*)__null) = 859; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
860 JS::ubi::AtomOrTwoByteChars s(atom);
861 return s.length();
862 },
863 [](const char16_t* chars) -> size_t {
864 MOZ_ASSERT(chars)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(chars)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(chars))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("chars", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 864); AnnotateMozCrashReason("MOZ_ASSERT" "(" "chars" ")");
do { *((volatile int*)__null) = 864; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false)
;
865 return NS_strlen(chars);
866 },
867 [](const JS::ubi::EdgeName& ptr) -> size_t {
868 MOZ_ASSERT(ptr)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 868); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ")"); do
{ *((volatile int*)__null) = 868; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
869 return NS_strlen(ptr.get());
870 });
871 }
872
873 // Copy the contents of a TwoByteString into the provided buffer. The buffer
874 // is NOT null terminated. The number of characters written is returned.
875 size_t copyToBuffer(RangedPtr<char16_t> destination, size_t maxLength) {
876 CopyToBufferMatcher m(destination, maxLength);
877 return match(m);
878 }
879
880 struct HashPolicy;
881};
882
883// A hashing policy for TwoByteString.
884//
885// Atoms are pointer hashed and use pointer equality, which means that we
886// tolerate some duplication across atoms and the other two types of two-byte
887// strings. In practice, we expect the amount of this duplication to be very low
888// because each type is generally a different semantic thing in addition to
889// having a slightly different representation. For example, the set of edge
890// names and the set stack frames' source names naturally tend not to overlap
891// very much if at all.
892struct TwoByteString::HashPolicy {
893 using Lookup = TwoByteString;
894
895 static js::HashNumber hash(const Lookup& l) {
896 return l.match(
897 [](const JSAtom* atom) {
898 return js::DefaultHasher<const JSAtom*>::hash(atom);
899 },
900 [](const char16_t* chars) {
901 MOZ_ASSERT(chars)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(chars)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(chars))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("chars", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 901); AnnotateMozCrashReason("MOZ_ASSERT" "(" "chars" ")");
do { *((volatile int*)__null) = 901; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false)
;
902 auto length = NS_strlen(chars);
903 return HashString(chars, length);
904 },
905 [](const JS::ubi::EdgeName& ptr) {
906 const char16_t* chars = ptr.get();
907 MOZ_ASSERT(chars)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(chars)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(chars))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("chars", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 907); AnnotateMozCrashReason("MOZ_ASSERT" "(" "chars" ")");
do { *((volatile int*)__null) = 907; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false)
;
908 auto length = NS_strlen(chars);
909 return HashString(chars, length);
910 });
911 }
912
913 struct EqualityMatcher {
914 const TwoByteString& rhs;
915 explicit EqualityMatcher(const TwoByteString& rhs) : rhs(rhs) {}
916
917 bool operator()(const JSAtom* atom) {
918 return rhs.is<JSAtom*>() && rhs.as<JSAtom*>() == atom;
919 }
920
921 bool operator()(const char16_t* chars) {
922 MOZ_ASSERT(chars)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(chars)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(chars))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("chars", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 922); AnnotateMozCrashReason("MOZ_ASSERT" "(" "chars" ")");
do { *((volatile int*)__null) = 922; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false)
;
923
924 const char16_t* rhsChars = nullptr;
925 if (rhs.is<const char16_t*>())
926 rhsChars = rhs.as<const char16_t*>();
927 else if (rhs.is<JS::ubi::EdgeName>())
928 rhsChars = rhs.as<JS::ubi::EdgeName>().get();
929 else
930 return false;
931 MOZ_ASSERT(rhsChars)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(rhsChars)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(rhsChars))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("rhsChars", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 931); AnnotateMozCrashReason("MOZ_ASSERT" "(" "rhsChars" ")"
); do { *((volatile int*)__null) = 931; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
932
933 auto length = NS_strlen(chars);
934 if (NS_strlen(rhsChars) != length) return false;
935
936 return memcmp(chars, rhsChars, length * sizeof(char16_t)) == 0;
937 }
938
939 bool operator()(const JS::ubi::EdgeName& ptr) {
940 MOZ_ASSERT(ptr)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 940); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ")"); do
{ *((volatile int*)__null) = 940; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
941 return operator()(ptr.get());
942 }
943 };
944
945 static bool match(const TwoByteString& k, const Lookup& l) {
946 EqualityMatcher eq(l);
947 return k.match(eq);
948 }
949
950 static void rekey(TwoByteString& k, TwoByteString&& newKey) {
951 k = std::move(newKey);
952 }
953};
954
955// Returns whether `edge` should be included in a heap snapshot of
956// `compartments`. The optional `policy` out-param is set to INCLUDE_EDGES
957// if we want to include the referent's edges, or EXCLUDE_EDGES if we don't
958// want to include them.
959static bool ShouldIncludeEdge(JS::CompartmentSet* compartments,
960 const ubi::Node& origin, const ubi::Edge& edge,
961 CoreDumpWriter::EdgePolicy* policy = nullptr) {
962 if (policy) {
963 *policy = CoreDumpWriter::INCLUDE_EDGES;
964 }
965
966 if (!compartments) {
967 // We aren't targeting a particular set of compartments, so serialize all
968 // the things!
969 return true;
970 }
971
972 // We are targeting a particular set of compartments. If this node is in our
973 // target set, serialize it and all of its edges. If this node is _not_ in our
974 // target set, we also serialize under the assumption that it is a shared
975 // resource being used by something in our target compartments since we
976 // reached it by traversing the heap graph. However, we do not serialize its
977 // outgoing edges and we abandon further traversal from this node.
978 //
979 // If the node does not belong to any compartment, we also serialize its
980 // outgoing edges. This case is relevant for Shapes: they don't belong to a
981 // specific compartment and contain edges to parent/kids Shapes we want to
982 // include. Note that these Shapes may contain pointers into our target
983 // compartment (the Shape's getter/setter JSObjects). However, we do not
984 // serialize nodes in other compartments that are reachable from these
985 // non-compartment nodes.
986
987 JS::Compartment* compartment = edge.referent.compartment();
988
989 if (!compartment || compartments->has(compartment)) {
990 return true;
991 }
992
993 if (policy) {
994 *policy = CoreDumpWriter::EXCLUDE_EDGES;
995 }
996
997 return !!origin.compartment();
998}
999
1000// A `CoreDumpWriter` that serializes nodes to protobufs and writes them to the
1001// given `ZeroCopyOutputStream`.
1002class MOZ_STACK_CLASS StreamWriter : public CoreDumpWriter {
1003 using FrameSet = js::HashSet<uint64_t>;
1004 using TwoByteStringMap =
1005 js::HashMap<TwoByteString, uint64_t, TwoByteString::HashPolicy>;
1006 using OneByteStringMap = js::HashMap<const char*, uint64_t>;
1007
1008 JSContext* cx;
1009 bool wantNames;
1010 // The set of |JS::ubi::StackFrame::identifier()|s that have already been
1011 // serialized and written to the core dump.
1012 FrameSet framesAlreadySerialized;
1013 // The set of two-byte strings that have already been serialized and written
1014 // to the core dump.
1015 TwoByteStringMap twoByteStringsAlreadySerialized;
1016 // The set of one-byte strings that have already been serialized and written
1017 // to the core dump.
1018 OneByteStringMap oneByteStringsAlreadySerialized;
1019
1020 ::google::protobuf::io::ZeroCopyOutputStream& stream;
1021
1022 JS::CompartmentSet* compartments;
1023
1024 bool writeMessage(const ::google::protobuf::MessageLite& message) {
1025 // We have to create a new CodedOutputStream when writing each message so
1026 // that the 64MB size limit used by Coded{Output,Input}Stream to prevent
1027 // integer overflow is enforced per message rather than on the whole stream.
1028 ::google::protobuf::io::CodedOutputStream codedStream(&stream);
1029 codedStream.WriteVarint32(message.ByteSizeLong());
1030 message.SerializeWithCachedSizes(&codedStream);
1031 return !codedStream.HadError();
1032 }
1033
1034 // Attach the full two-byte string or a reference to a two-byte string that
1035 // has already been serialized to a protobuf message.
1036 template <typename SetStringFunction, typename SetRefFunction>
1037 bool attachTwoByteString(TwoByteString& string, SetStringFunction setString,
1038 SetRefFunction setRef) {
1039 auto ptr = twoByteStringsAlreadySerialized.lookupForAdd(string);
1040 if (ptr) {
1041 setRef(ptr->value());
1042 return true;
1043 }
1044
1045 auto length = string.length();
1046 auto stringData = MakeUnique<std::string>(length * sizeof(char16_t), '\0');
1047 if (!stringData) return false;
1048
1049 auto buf = const_cast<char16_t*>(
1050 reinterpret_cast<const char16_t*>(stringData->data()));
1051 string.copyToBuffer(RangedPtr<char16_t>(buf, length), length);
1052
1053 uint64_t ref = twoByteStringsAlreadySerialized.count();
1054 if (!twoByteStringsAlreadySerialized.add(ptr, std::move(string), ref))
1055 return false;
1056
1057 setString(stringData.release());
1058 return true;
1059 }
1060
1061 // Attach the full one-byte string or a reference to a one-byte string that
1062 // has already been serialized to a protobuf message.
1063 template <typename SetStringFunction, typename SetRefFunction>
1064 bool attachOneByteString(const char* string, SetStringFunction setString,
1065 SetRefFunction setRef) {
1066 auto ptr = oneByteStringsAlreadySerialized.lookupForAdd(string);
1067 if (ptr) {
1068 setRef(ptr->value());
1069 return true;
1070 }
1071
1072 auto length = strlen(string);
1073 auto stringData = MakeUnique<std::string>(string, length);
1074 if (!stringData) return false;
1075
1076 uint64_t ref = oneByteStringsAlreadySerialized.count();
1077 if (!oneByteStringsAlreadySerialized.add(ptr, string, ref)) return false;
1078
1079 setString(stringData.release());
1080 return true;
1081 }
1082
1083 protobuf::StackFrame* getProtobufStackFrame(JS::ubi::StackFrame& frame,
1084 size_t depth = 1) {
1085 // NB: de-duplicated string properties must be written in the same order
1086 // here as they are read in `HeapSnapshot::saveStackFrame` or else indices
1087 // in references to already serialized strings will be off.
1088
1089 MOZ_ASSERT(frame,do { static_assert( mozilla::detail::AssertionConditionType<
decltype(frame)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(frame))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("frame" " (" "null frames should be represented as the lack of a serialized "
"stack frame" ")", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1091); AnnotateMozCrashReason("MOZ_ASSERT" "(" "frame" ") ("
"null frames should be represented as the lack of a serialized "
"stack frame" ")"); do { *((volatile int*)__null) = 1091; __attribute__
((nomerge)) ::abort(); } while (false); } } while (false)
1090 "null frames should be represented as the lack of a serialized "do { static_assert( mozilla::detail::AssertionConditionType<
decltype(frame)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(frame))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("frame" " (" "null frames should be represented as the lack of a serialized "
"stack frame" ")", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1091); AnnotateMozCrashReason("MOZ_ASSERT" "(" "frame" ") ("
"null frames should be represented as the lack of a serialized "
"stack frame" ")"); do { *((volatile int*)__null) = 1091; __attribute__
((nomerge)) ::abort(); } while (false); } } while (false)
1091 "stack frame")do { static_assert( mozilla::detail::AssertionConditionType<
decltype(frame)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(frame))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("frame" " (" "null frames should be represented as the lack of a serialized "
"stack frame" ")", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1091); AnnotateMozCrashReason("MOZ_ASSERT" "(" "frame" ") ("
"null frames should be represented as the lack of a serialized "
"stack frame" ")"); do { *((volatile int*)__null) = 1091; __attribute__
((nomerge)) ::abort(); } while (false); } } while (false)
;
1092
1093 auto id = frame.identifier();
1094 auto protobufStackFrame = MakeUnique<protobuf::StackFrame>();
1095 if (!protobufStackFrame) return nullptr;
1096
1097 if (framesAlreadySerialized.has(id)) {
1098 protobufStackFrame->set_ref(id);
1099 return protobufStackFrame.release();
1100 }
1101
1102 auto data = MakeUnique<protobuf::StackFrame_Data>();
1103 if (!data) return nullptr;
1104
1105 data->set_id(id);
1106 data->set_line(frame.line());
1107 data->set_column(frame.column().oneOriginValue());
1108 data->set_issystem(frame.isSystem());
1109 data->set_isselfhosted(frame.isSelfHosted(cx));
1110
1111 auto dupeSource = TwoByteString::from(frame.source());
1112 if (!attachTwoByteString(
1113 dupeSource,
1114 [&](std::string* source) { data->set_allocated_source(source); },
1115 [&](uint64_t ref) { data->set_sourceref(ref); })) {
1116 return nullptr;
1117 }
1118
1119 auto dupeName = TwoByteString::from(frame.functionDisplayName());
1120 if (dupeName.isNonNull()) {
1121 if (!attachTwoByteString(
1122 dupeName,
1123 [&](std::string* name) {
1124 data->set_allocated_functiondisplayname(name);
1125 },
1126 [&](uint64_t ref) { data->set_functiondisplaynameref(ref); })) {
1127 return nullptr;
1128 }
1129 }
1130
1131 auto parent = frame.parent();
1132 if (parent && depth < HeapSnapshot::MAX_STACK_DEPTH) {
1133 auto protobufParent = getProtobufStackFrame(parent, depth + 1);
1134 if (!protobufParent) return nullptr;
1135 data->set_allocated_parent(protobufParent);
1136 }
1137
1138 protobufStackFrame->set_allocated_data(data.release());
1139
1140 if (!framesAlreadySerialized.put(id)) return nullptr;
1141
1142 return protobufStackFrame.release();
1143 }
1144
1145 public:
1146 StreamWriter(JSContext* cx,
1147 ::google::protobuf::io::ZeroCopyOutputStream& stream,
1148 bool wantNames, JS::CompartmentSet* compartments)
1149 : cx(cx),
1150 wantNames(wantNames),
1151 framesAlreadySerialized(cx),
1152 twoByteStringsAlreadySerialized(cx),
1153 oneByteStringsAlreadySerialized(cx),
1154 stream(stream),
1155 compartments(compartments) {}
1156
1157 ~StreamWriter() override {}
1158
1159 bool writeMetadata(uint64_t timestamp) final {
1160 protobuf::Metadata metadata;
1161 metadata.set_timestamp(timestamp);
1162 return writeMessage(metadata);
1163 }
1164
1165 bool writeNode(const JS::ubi::Node& ubiNode, EdgePolicy includeEdges) final {
1166 // NB: de-duplicated string properties must be written in the same order
1167 // here as they are read in `HeapSnapshot::saveNode` or else indices in
1168 // references to already serialized strings will be off.
1169
1170 protobuf::Node protobufNode;
1171 protobufNode.set_id(ubiNode.identifier());
1172
1173 protobufNode.set_coarsetype(
1174 JS::ubi::CoarseTypeToUint32(ubiNode.coarseType()));
1175
1176 auto typeName = TwoByteString(ubiNode.typeName());
1177 if (NS_WARN_IF(!attachTwoByteString(NS_warn_if_impl(!attachTwoByteString( typeName, [&](std::
string* name) { protobufNode.set_allocated_typename_(name); }
, [&](uint64_t ref) { protobufNode.set_typenameref(ref); }
), "!attachTwoByteString( typeName, [&](std::string* name) { protobufNode.set_allocated_typename_(name); }, [&](uint64_t ref) { protobufNode.set_typenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1182)
1178 typeName,NS_warn_if_impl(!attachTwoByteString( typeName, [&](std::
string* name) { protobufNode.set_allocated_typename_(name); }
, [&](uint64_t ref) { protobufNode.set_typenameref(ref); }
), "!attachTwoByteString( typeName, [&](std::string* name) { protobufNode.set_allocated_typename_(name); }, [&](uint64_t ref) { protobufNode.set_typenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1182)
1179 [&](std::string* name) {NS_warn_if_impl(!attachTwoByteString( typeName, [&](std::
string* name) { protobufNode.set_allocated_typename_(name); }
, [&](uint64_t ref) { protobufNode.set_typenameref(ref); }
), "!attachTwoByteString( typeName, [&](std::string* name) { protobufNode.set_allocated_typename_(name); }, [&](uint64_t ref) { protobufNode.set_typenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1182)
1180 protobufNode.set_allocated_typename_(name);NS_warn_if_impl(!attachTwoByteString( typeName, [&](std::
string* name) { protobufNode.set_allocated_typename_(name); }
, [&](uint64_t ref) { protobufNode.set_typenameref(ref); }
), "!attachTwoByteString( typeName, [&](std::string* name) { protobufNode.set_allocated_typename_(name); }, [&](uint64_t ref) { protobufNode.set_typenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1182)
1181 },NS_warn_if_impl(!attachTwoByteString( typeName, [&](std::
string* name) { protobufNode.set_allocated_typename_(name); }
, [&](uint64_t ref) { protobufNode.set_typenameref(ref); }
), "!attachTwoByteString( typeName, [&](std::string* name) { protobufNode.set_allocated_typename_(name); }, [&](uint64_t ref) { protobufNode.set_typenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1182)
1182 [&](uint64_t ref) { protobufNode.set_typenameref(ref); }))NS_warn_if_impl(!attachTwoByteString( typeName, [&](std::
string* name) { protobufNode.set_allocated_typename_(name); }
, [&](uint64_t ref) { protobufNode.set_typenameref(ref); }
), "!attachTwoByteString( typeName, [&](std::string* name) { protobufNode.set_allocated_typename_(name); }, [&](uint64_t ref) { protobufNode.set_typenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1182)
) {
1183 return false;
1184 }
1185
1186 mozilla::MallocSizeOf mallocSizeOf = dbg::GetDebuggerMallocSizeOf(cx);
1187 MOZ_ASSERT(mallocSizeOf)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mallocSizeOf)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(mallocSizeOf))), 0))) { do {
} while (false); MOZ_ReportAssertionFailure("mallocSizeOf", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1187); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mallocSizeOf"
")"); do { *((volatile int*)__null) = 1187; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1188 protobufNode.set_size(ubiNode.size(mallocSizeOf));
1189
1190 if (includeEdges) {
1191 auto edges = ubiNode.edges(cx, wantNames);
1192 if (NS_WARN_IF(!edges)NS_warn_if_impl(!edges, "!edges", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1192)
) return false;
1193
1194 for (; !edges->empty(); edges->popFront()) {
1195 ubi::Edge& ubiEdge = edges->front();
1196 if (!ShouldIncludeEdge(compartments, ubiNode, ubiEdge)) {
1197 continue;
1198 }
1199
1200 protobuf::Edge* protobufEdge = protobufNode.add_edges();
1201 if (NS_WARN_IF(!protobufEdge)NS_warn_if_impl(!protobufEdge, "!protobufEdge", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1201)
) {
1202 return false;
1203 }
1204
1205 protobufEdge->set_referent(ubiEdge.referent.identifier());
1206
1207 if (wantNames && ubiEdge.name) {
1208 TwoByteString edgeName(std::move(ubiEdge.name));
1209 if (NS_WARN_IF(!attachTwoByteString(NS_warn_if_impl(!attachTwoByteString( edgeName, [&](std::
string* name) { protobufEdge->set_allocated_name(name); },
[&](uint64_t ref) { protobufEdge->set_nameref(ref); }
), "!attachTwoByteString( edgeName, [&](std::string* name) { protobufEdge->set_allocated_name(name); }, [&](uint64_t ref) { protobufEdge->set_nameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1214)
1210 edgeName,NS_warn_if_impl(!attachTwoByteString( edgeName, [&](std::
string* name) { protobufEdge->set_allocated_name(name); },
[&](uint64_t ref) { protobufEdge->set_nameref(ref); }
), "!attachTwoByteString( edgeName, [&](std::string* name) { protobufEdge->set_allocated_name(name); }, [&](uint64_t ref) { protobufEdge->set_nameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1214)
1211 [&](std::string* name) {NS_warn_if_impl(!attachTwoByteString( edgeName, [&](std::
string* name) { protobufEdge->set_allocated_name(name); },
[&](uint64_t ref) { protobufEdge->set_nameref(ref); }
), "!attachTwoByteString( edgeName, [&](std::string* name) { protobufEdge->set_allocated_name(name); }, [&](uint64_t ref) { protobufEdge->set_nameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1214)
1212 protobufEdge->set_allocated_name(name);NS_warn_if_impl(!attachTwoByteString( edgeName, [&](std::
string* name) { protobufEdge->set_allocated_name(name); },
[&](uint64_t ref) { protobufEdge->set_nameref(ref); }
), "!attachTwoByteString( edgeName, [&](std::string* name) { protobufEdge->set_allocated_name(name); }, [&](uint64_t ref) { protobufEdge->set_nameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1214)
1213 },NS_warn_if_impl(!attachTwoByteString( edgeName, [&](std::
string* name) { protobufEdge->set_allocated_name(name); },
[&](uint64_t ref) { protobufEdge->set_nameref(ref); }
), "!attachTwoByteString( edgeName, [&](std::string* name) { protobufEdge->set_allocated_name(name); }, [&](uint64_t ref) { protobufEdge->set_nameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1214)
1214 [&](uint64_t ref) { protobufEdge->set_nameref(ref); }))NS_warn_if_impl(!attachTwoByteString( edgeName, [&](std::
string* name) { protobufEdge->set_allocated_name(name); },
[&](uint64_t ref) { protobufEdge->set_nameref(ref); }
), "!attachTwoByteString( edgeName, [&](std::string* name) { protobufEdge->set_allocated_name(name); }, [&](uint64_t ref) { protobufEdge->set_nameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1214)
) {
1215 return false;
1216 }
1217 }
1218 }
1219 }
1220
1221 if (ubiNode.hasAllocationStack()) {
1222 auto ubiStackFrame = ubiNode.allocationStack();
1223 auto protoStackFrame = getProtobufStackFrame(ubiStackFrame);
1224 if (NS_WARN_IF(!protoStackFrame)NS_warn_if_impl(!protoStackFrame, "!protoStackFrame", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1224)
) return false;
1225 protobufNode.set_allocated_allocationstack(protoStackFrame);
1226 }
1227
1228 if (auto className = ubiNode.jsObjectClassName()) {
1229 if (NS_WARN_IF(!attachOneByteString(NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
1230 className,NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
1231 [&](std::string* name) {NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
1232 protobufNode.set_allocated_jsobjectclassname(name);NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
1233 },NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
1234 [&](uint64_t ref) {NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
1235 protobufNode.set_jsobjectclassnameref(ref);NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
1236 }))NS_warn_if_impl(!attachOneByteString( className, [&](std::
string* name) { protobufNode.set_allocated_jsobjectclassname(
name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref
(ref); }), "!attachOneByteString( className, [&](std::string* name) { protobufNode.set_allocated_jsobjectclassname(name); }, [&](uint64_t ref) { protobufNode.set_jsobjectclassnameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1236)
) {
1237 return false;
1238 }
1239 }
1240
1241 if (auto scriptFilename = ubiNode.scriptFilename()) {
1242 if (NS_WARN_IF(!attachOneByteString(NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
1243 scriptFilename,NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
1244 [&](std::string* name) {NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
1245 protobufNode.set_allocated_scriptfilename(name);NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
1246 },NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
1247 [&](uint64_t ref) {NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
1248 protobufNode.set_scriptfilenameref(ref);NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
1249 }))NS_warn_if_impl(!attachOneByteString( scriptFilename, [&]
(std::string* name) { protobufNode.set_allocated_scriptfilename
(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref
(ref); }), "!attachOneByteString( scriptFilename, [&](std::string* name) { protobufNode.set_allocated_scriptfilename(name); }, [&](uint64_t ref) { protobufNode.set_scriptfilenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1249)
) {
1250 return false;
1251 }
1252 }
1253
1254 if (ubiNode.descriptiveTypeName()) {
1255 auto descriptiveTypeName = TwoByteString(ubiNode.descriptiveTypeName());
1256 if (NS_WARN_IF(!attachTwoByteString(NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
1257 descriptiveTypeName,NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
1258 [&](std::string* name) {NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
1259 protobufNode.set_allocated_descriptivetypename(name);NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
1260 },NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
1261 [&](uint64_t ref) {NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
1262 protobufNode.set_descriptivetypenameref(ref);NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
1263 }))NS_warn_if_impl(!attachTwoByteString( descriptiveTypeName, [&
](std::string* name) { protobufNode.set_allocated_descriptivetypename
(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref
(ref); }), "!attachTwoByteString( descriptiveTypeName, [&](std::string* name) { protobufNode.set_allocated_descriptivetypename(name); }, [&](uint64_t ref) { protobufNode.set_descriptivetypenameref(ref); })"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1263)
) {
1264 return false;
1265 }
1266 }
1267
1268 return writeMessage(protobufNode);
1269 }
1270};
1271
1272// A JS::ubi::BreadthFirst handler that serializes a snapshot of the heap into a
1273// core dump.
1274class MOZ_STACK_CLASS HeapSnapshotHandler {
1275 CoreDumpWriter& writer;
1276 JS::CompartmentSet* compartments;
1277
1278 public:
1279 // For telemetry.
1280 uint32_t nodeCount;
1281 uint32_t edgeCount;
1282
1283 HeapSnapshotHandler(CoreDumpWriter& writer, JS::CompartmentSet* compartments)
1284 : writer(writer),
1285 compartments(compartments),
1286 nodeCount(0),
1287 edgeCount(0) {}
1288
1289 // JS::ubi::BreadthFirst handler interface.
1290
1291 class NodeData {};
1292 typedef JS::ubi::BreadthFirst<HeapSnapshotHandler> Traversal;
1293 bool operator()(Traversal& traversal, JS::ubi::Node origin,
1294 const JS::ubi::Edge& edge, NodeData*, bool first) {
1295 edgeCount++;
1296
1297 // We're only interested in the first time we reach edge.referent, not in
1298 // every edge arriving at that node. "But, don't we want to serialize every
1299 // edge in the heap graph?" you ask. Don't worry! This edge is still
1300 // serialized into the core dump. Serializing a node also serializes each of
1301 // its edges, and if we are traversing a given edge, we must have already
1302 // visited and serialized the origin node and its edges.
1303 if (!first) return true;
1304
1305 CoreDumpWriter::EdgePolicy policy;
1306 if (!ShouldIncludeEdge(compartments, origin, edge, &policy)) {
1307 // Because ShouldIncludeEdge considers the |origin| node as well, we don't
1308 // want to consider this node 'visited' until we write it to the core
1309 // dump.
1310 traversal.doNotMarkReferentAsVisited();
1311 return true;
1312 }
1313
1314 nodeCount++;
1315
1316 if (policy == CoreDumpWriter::EXCLUDE_EDGES) traversal.abandonReferent();
1317
1318 return writer.writeNode(edge.referent, policy);
1319 }
1320};
1321
1322bool WriteHeapGraph(JSContext* cx, const JS::ubi::Node& node,
1323 CoreDumpWriter& writer, bool wantNames,
1324 JS::CompartmentSet* compartments,
1325 JS::AutoCheckCannotGC& noGC, uint32_t& outNodeCount,
1326 uint32_t& outEdgeCount) {
1327 // Serialize the starting node to the core dump.
1328
1329 if (NS_WARN_IF(!writer.writeNode(node, CoreDumpWriter::INCLUDE_EDGES))NS_warn_if_impl(!writer.writeNode(node, CoreDumpWriter::INCLUDE_EDGES
), "!writer.writeNode(node, CoreDumpWriter::INCLUDE_EDGES)", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1329)
) {
1330 return false;
1331 }
1332
1333 // Walk the heap graph starting from the given node and serialize it into the
1334 // core dump.
1335
1336 HeapSnapshotHandler handler(writer, compartments);
1337 HeapSnapshotHandler::Traversal traversal(cx, handler, noGC);
1338 traversal.wantNames = wantNames;
1339
1340 bool ok = traversal.addStartVisited(node) && traversal.traverse();
1341
1342 if (ok) {
1343 outNodeCount = handler.nodeCount;
1344 outEdgeCount = handler.edgeCount;
1345 }
1346
1347 return ok;
1348}
1349
1350static unsigned long msSinceProcessCreation(const TimeStamp& now) {
1351 auto duration = now - TimeStamp::ProcessCreation();
1352 return (unsigned long)duration.ToMilliseconds();
1353}
1354
1355/* static */
1356already_AddRefed<nsIFile> HeapSnapshot::CreateUniqueCoreDumpFile(
1357 ErrorResult& rv, const TimeStamp& now, nsAString& outFilePath,
1358 nsAString& outSnapshotId) {
1359 MOZ_RELEASE_ASSERT(XRE_IsParentProcess())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(XRE_IsParentProcess())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(XRE_IsParentProcess()))), 0)
)) { do { } while (false); MOZ_ReportAssertionFailure("XRE_IsParentProcess()"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1359); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "XRE_IsParentProcess()"
")"); do { *((volatile int*)__null) = 1359; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1360 nsCOMPtr<nsIFile> file;
1361 rv = GetSpecialSystemDirectory(OS_TemporaryDirectory, getter_AddRefs(file));
1362 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1362)
) return nullptr;
1363
1364 nsAutoString tempPath;
1365 rv = file->GetPath(tempPath);
1366 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1366)
) return nullptr;
1367
1368 auto ms = msSinceProcessCreation(now);
1369 rv = file->AppendNative(nsPrintfCString("%lu.fxsnapshot", ms));
1370 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1370)
) return nullptr;
1371
1372 rv = file->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0666);
1373 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1373)
) return nullptr;
1374
1375 rv = file->GetPath(outFilePath);
1376 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1376)
) return nullptr;
1377
1378 // The snapshot ID must be computed in the process that created the
1379 // temp file, because TmpD may not be the same in all processes.
1380 outSnapshotId.Assign(Substring(
1381 outFilePath, tempPath.Length() + 1,
1382 outFilePath.Length() - tempPath.Length() - sizeof(".fxsnapshot")));
1383
1384 return file.forget();
1385}
1386
1387// Deletion policy for cleaning up PHeapSnapshotTempFileHelperChild pointers.
1388class DeleteHeapSnapshotTempFileHelperChild {
1389 public:
1390 constexpr DeleteHeapSnapshotTempFileHelperChild() {}
1391
1392 void operator()(PHeapSnapshotTempFileHelperChild* ptr) const {
1393 Unused << NS_WARN_IF(!HeapSnapshotTempFileHelperChild::Send__delete__(ptr))NS_warn_if_impl(!HeapSnapshotTempFileHelperChild::Send__delete__
(ptr), "!HeapSnapshotTempFileHelperChild::Send__delete__(ptr)"
, "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1393)
;
1394 }
1395};
1396
1397// A UniquePtr alias to automatically manage PHeapSnapshotTempFileHelperChild
1398// pointers.
1399using UniqueHeapSnapshotTempFileHelperChild =
1400 UniquePtr<PHeapSnapshotTempFileHelperChild,
1401 DeleteHeapSnapshotTempFileHelperChild>;
1402
1403// Get an nsIOutputStream that we can write the heap snapshot to. In non-e10s
1404// and in the e10s parent process, open a file directly and create an output
1405// stream for it. In e10s child processes, we are sandboxed without access to
1406// the filesystem. Use IPDL to request a file descriptor from the parent
1407// process.
1408static already_AddRefed<nsIOutputStream> getCoreDumpOutputStream(
1409 ErrorResult& rv, TimeStamp& start, nsAString& outFilePath,
1410 nsAString& outSnapshotId) {
1411 if (XRE_IsParentProcess()) {
1412 // Create the file and open the output stream directly.
1413
1414 nsCOMPtr<nsIFile> file = HeapSnapshot::CreateUniqueCoreDumpFile(
1415 rv, start, outFilePath, outSnapshotId);
1416 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1416)
) return nullptr;
1417
1418 nsCOMPtr<nsIOutputStream> outputStream;
1419 rv = NS_NewLocalFileOutputStream(getter_AddRefs(outputStream), file,
1420 PR_WRONLY0x02, -1, 0);
1421 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1421)
) return nullptr;
1422
1423 return outputStream.forget();
1424 }
1425 // Request a file descriptor from the parent process over IPDL.
1426
1427 auto cc = ContentChild::GetSingleton();
1428 if (!cc) {
1429 rv.Throw(NS_ERROR_UNEXPECTED);
1430 return nullptr;
1431 }
1432
1433 UniqueHeapSnapshotTempFileHelperChild helper(
1434 cc->SendPHeapSnapshotTempFileHelperConstructor());
1435 if (NS_WARN_IF(!helper)NS_warn_if_impl(!helper, "!helper", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1435)
) {
1436 rv.Throw(NS_ERROR_UNEXPECTED);
1437 return nullptr;
1438 }
1439
1440 OpenHeapSnapshotTempFileResponse response;
1441 if (!helper->SendOpenHeapSnapshotTempFile(&response)) {
1442 rv.Throw(NS_ERROR_UNEXPECTED);
1443 return nullptr;
1444 }
1445 if (response.type() == OpenHeapSnapshotTempFileResponse::Tnsresult) {
1446 rv.Throw(response.get_nsresult());
1447 return nullptr;
1448 }
1449
1450 auto opened = response.get_OpenedFile();
1451 outFilePath = opened.path();
1452 outSnapshotId = opened.snapshotId();
1453 nsCOMPtr<nsIOutputStream> outputStream =
1454 FileDescriptorOutputStream::Create(opened.descriptor());
1455 if (NS_WARN_IF(!outputStream)NS_warn_if_impl(!outputStream, "!outputStream", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1455)
) {
1456 rv.Throw(NS_ERROR_UNEXPECTED);
1457 return nullptr;
1458 }
1459
1460 return outputStream.forget();
1461}
1462
1463} // namespace devtools
1464
1465namespace dom {
1466
1467using namespace JS;
1468using namespace devtools;
1469
1470/* static */
1471void ChromeUtils::SaveHeapSnapshotShared(
1472 GlobalObject& global, const HeapSnapshotBoundaries& boundaries,
1473 nsAString& outFilePath, nsAString& outSnapshotId, ErrorResult& rv) {
1474 auto start = TimeStamp::Now();
1475
1476 bool wantNames = true;
1477 CompartmentSet compartments;
1478 uint32_t nodeCount = 0;
1479 uint32_t edgeCount = 0;
1480
1481 nsCOMPtr<nsIOutputStream> outputStream =
1482 getCoreDumpOutputStream(rv, start, outFilePath, outSnapshotId);
1483 if (NS_WARN_IF(rv.Failed())NS_warn_if_impl(rv.Failed(), "rv.Failed()", "/var/lib/jenkins/workspace/firefox-scan-build/devtools/shared/heapsnapshot/HeapSnapshot.cpp"
, 1483)
) return;
1484
1485 ZeroCopyNSIOutputStream zeroCopyStream(outputStream);
1486 ::google::protobuf::io::GzipOutputStream gzipStream(&zeroCopyStream);
1487
1488 JSContext* cx = global.Context();
1489
1490 {
1491 ubi::RootList rootList(cx, wantNames);
1492 auto [ok, nogc] =
1493 EstablishBoundaries(cx, rv, boundaries, rootList, compartments);
1494 if (!ok) {
1495 return;
1496 }
1497
1498 StreamWriter writer(cx, gzipStream, wantNames,
1499 !compartments.empty() ? &compartments : nullptr);
1500
1501 ubi::Node roots(&rootList);
1502
1503 // Serialize the initial heap snapshot metadata to the core dump.
1504 if (!writer.writeMetadata(PR_Now()) ||
1505 // Serialize the heap graph to the core dump, starting from our list of
1506 // roots.
1507 !WriteHeapGraph(cx, roots, writer, wantNames,
1508 !compartments.empty() ? &compartments : nullptr, nogc,
1509 nodeCount, edgeCount)) {
1510 rv.Throw(zeroCopyStream.failed() ? zeroCopyStream.result()
1511 : NS_ERROR_UNEXPECTED);
1512 return;
1513 }
1514 }
1515
1516 Telemetry::AccumulateTimeDelta(Telemetry::DEVTOOLS_SAVE_HEAP_SNAPSHOT_MS,
1517 start);
1518 Telemetry::Accumulate(Telemetry::DEVTOOLS_HEAP_SNAPSHOT_NODE_COUNT,
1519 nodeCount);
1520 Telemetry::Accumulate(Telemetry::DEVTOOLS_HEAP_SNAPSHOT_EDGE_COUNT,
1521 edgeCount);
1522}
1523
1524/* static */
1525uint64_t ChromeUtils::GetObjectNodeId(GlobalObject& global,
1526 JS::Handle<JSObject*> val) {
1527 JS::Rooted<JSObject*> obj(global.Context(), val);
1528
1529 JS::ubi::Node node(obj);
1530 return node.identifier();
1531}
1532
1533/* static */
1534void ChromeUtils::SaveHeapSnapshot(GlobalObject& global,
1535 const HeapSnapshotBoundaries& boundaries,
1536 nsAString& outFilePath, ErrorResult& rv) {
1537 nsAutoString snapshotId;
1538 SaveHeapSnapshotShared(global, boundaries, outFilePath, snapshotId, rv);
1539}
1540
1541/* static */
1542void ChromeUtils::SaveHeapSnapshotGetId(
1543 GlobalObject& global, const HeapSnapshotBoundaries& boundaries,
1544 nsAString& outSnapshotId, ErrorResult& rv) {
1545 nsAutoString filePath;
1546 SaveHeapSnapshotShared(global, boundaries, filePath, outSnapshotId, rv);
1547}
1548
1549/* static */
1550already_AddRefed<HeapSnapshot> ChromeUtils::ReadHeapSnapshot(
1551 GlobalObject& global, const nsAString& filePath, ErrorResult& rv) {
1552 auto start = TimeStamp::Now();
1553
1554 nsresult nsrv;
1555 nsCOMPtr<nsIFile> snapshotFile =
1556 do_CreateInstance("@mozilla.org/file/local;1", &nsrv);
1557
1558 if (NS_FAILED(nsrv)((bool)(__builtin_expect(!!(NS_FAILED_impl(nsrv)), 0)))) {
1559 rv = nsrv;
1560 return nullptr;
1561 }
1562
1563 rv = snapshotFile->InitWithPath(filePath);
1564 if (rv.Failed()) {
1565 return nullptr;
1566 }
1567
1568 AutoMemMap mm;
1569 rv = mm.init(snapshotFile);
1570 if (rv.Failed()) return nullptr;
1571
1572 RefPtr<HeapSnapshot> snapshot = HeapSnapshot::Create(
1573 global.Context(), global, reinterpret_cast<const uint8_t*>(mm.address()),
1574 mm.size(), rv);
1575
1576 if (!rv.Failed())
1577 Telemetry::AccumulateTimeDelta(Telemetry::DEVTOOLS_READ_HEAP_SNAPSHOT_MS,
1578 start);
1579
1580 return snapshot.forget();
1581}
1582
1583} // namespace dom
1584} // namespace mozilla

/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h

1/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2/* vim: set ts=8 sts=2 et sw=2 tw=80: */
3/* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7/* A class for optional values and in-place lazy construction. */
8
9#ifndef mozilla_Maybe_h
10#define mozilla_Maybe_h
11
12#include <functional>
13#include <new> // for placement new
14#include <ostream>
15#include <type_traits>
16#include <utility>
17
18#include "mozilla/Alignment.h"
19#include "mozilla/Assertions.h"
20#include "mozilla/Attributes.h"
21#include "mozilla/MaybeStorageBase.h"
22#include "mozilla/MemoryChecking.h"
23#include "mozilla/OperatorNewExtensions.h"
24#include "mozilla/Poison.h"
25#include "mozilla/ThreadSafety.h"
26
27class nsCycleCollectionTraversalCallback;
28
29template <typename T>
30inline void CycleCollectionNoteChild(
31 nsCycleCollectionTraversalCallback& aCallback, T* aChild, const char* aName,
32 uint32_t aFlags);
33
34namespace mozilla {
35
36struct Nothing {};
37
38inline constexpr bool operator==(const Nothing&, const Nothing&) {
39 return true;
40}
41
42template <class T>
43class Maybe;
44
45namespace detail {
46
47// You would think that poisoning Maybe instances could just be a call
48// to mozWritePoison. Unfortunately, using a simple call to
49// mozWritePoison generates poor code on MSVC for small structures. The
50// generated code contains (always not-taken) branches and does a bunch
51// of setup for `rep stos{l,q}`, even though we know at compile time
52// exactly how many words we're poisoning. Instead, we're going to
53// force MSVC to generate the code we want via recursive templates.
54
55// Write the given poisonValue into p at offset*sizeof(uintptr_t).
56template <size_t offset>
57inline void WritePoisonAtOffset(void* p, const uintptr_t poisonValue) {
58 memcpy(static_cast<char*>(p) + offset * sizeof(poisonValue), &poisonValue,
59 sizeof(poisonValue));
60}
61
62template <size_t Offset, size_t NOffsets>
63struct InlinePoisoner {
64 static void poison(void* p, const uintptr_t poisonValue) {
65 WritePoisonAtOffset<Offset>(p, poisonValue);
66 InlinePoisoner<Offset + 1, NOffsets>::poison(p, poisonValue);
67 }
68};
69
70template <size_t N>
71struct InlinePoisoner<N, N> {
72 static void poison(void*, const uintptr_t) {
73 // All done!
74 }
75};
76
77// We can't generate inline code for large structures, though, because we'll
78// blow out recursive template instantiation limits, and the code would be
79// bloated to boot. So provide a fallback to the out-of-line poisoner.
80template <size_t ObjectSize>
81struct OutOfLinePoisoner {
82 static MOZ_NEVER_INLINE__attribute__((noinline)) void poison(void* p, const uintptr_t) {
83 mozWritePoison(p, ObjectSize);
84 }
85};
86
87template <typename T>
88inline void PoisonObject(T* p) {
89 const uintptr_t POISON = mozPoisonValue();
90 std::conditional_t<(sizeof(T) <= 8 * sizeof(POISON)),
91 InlinePoisoner<0, sizeof(T) / sizeof(POISON)>,
92 OutOfLinePoisoner<sizeof(T)>>::poison(p, POISON);
93}
94
95template <typename T>
96struct MaybePoisoner {
97 static const size_t N = sizeof(T);
98
99 static void poison(void* aPtr) {
100#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED1
101 if (N >= sizeof(uintptr_t)) {
102 PoisonObject(static_cast<std::remove_cv_t<T>*>(aPtr));
103 }
104#endif
105 MOZ_MAKE_MEM_UNDEFINED(aPtr, N)do { } while (0);
106 }
107};
108
109template <typename T,
110 bool TriviallyDestructibleAndCopyable =
111 IsTriviallyDestructibleAndCopyable<T>,
112 bool Copyable = std::is_copy_constructible_v<T>,
113 bool Movable = std::is_move_constructible_v<T>>
114class Maybe_CopyMove_Enabler;
115
116#define MOZ_MAYBE_COPY_OPS() \
117 Maybe_CopyMove_Enabler(const Maybe_CopyMove_Enabler& aOther) { \
118 if (downcast(aOther).isSome()) { \
119 downcast(*this).emplace(*downcast(aOther)); \
120 } \
121 } \
122 \
123 Maybe_CopyMove_Enabler& operator=(const Maybe_CopyMove_Enabler& aOther) { \
124 return downcast(*this).template operator= <T>(downcast(aOther)); \
125 }
126
127#define MOZ_MAYBE_MOVE_OPS() \
128 constexpr Maybe_CopyMove_Enabler(Maybe_CopyMove_Enabler&& aOther) { \
129 if (downcast(aOther).isSome()) { \
130 downcast(*this).emplace(std::move(*downcast(aOther))); \
131 downcast(aOther).reset(); \
132 } \
133 } \
134 \
135 constexpr Maybe_CopyMove_Enabler& operator=( \
136 Maybe_CopyMove_Enabler&& aOther) { \
137 downcast(*this).template operator= <T>(std::move(downcast(aOther))); \
138 \
139 return *this; \
140 }
141
142#define MOZ_MAYBE_DOWNCAST() \
143 static constexpr Maybe<T>& downcast(Maybe_CopyMove_Enabler& aObj) { \
144 return static_cast<Maybe<T>&>(aObj); \
145 } \
146 static constexpr const Maybe<T>& downcast( \
147 const Maybe_CopyMove_Enabler& aObj) { \
148 return static_cast<const Maybe<T>&>(aObj); \
149 }
150
151template <typename T>
152class Maybe_CopyMove_Enabler<T, true, true, true> {
153 public:
154 Maybe_CopyMove_Enabler() = default;
155
156 Maybe_CopyMove_Enabler(const Maybe_CopyMove_Enabler&) = default;
157 Maybe_CopyMove_Enabler& operator=(const Maybe_CopyMove_Enabler&) = default;
158 constexpr Maybe_CopyMove_Enabler(Maybe_CopyMove_Enabler&& aOther) {
159 downcast(aOther).reset();
160 }
161 constexpr Maybe_CopyMove_Enabler& operator=(Maybe_CopyMove_Enabler&& aOther) {
162 downcast(aOther).reset();
163 return *this;
164 }
165
166 private:
167 MOZ_MAYBE_DOWNCAST()
168};
169
170template <typename T>
171class Maybe_CopyMove_Enabler<T, true, false, true> {
172 public:
173 Maybe_CopyMove_Enabler() = default;
174
175 Maybe_CopyMove_Enabler(const Maybe_CopyMove_Enabler&) = delete;
176 Maybe_CopyMove_Enabler& operator=(const Maybe_CopyMove_Enabler&) = delete;
177 constexpr Maybe_CopyMove_Enabler(Maybe_CopyMove_Enabler&& aOther) {
178 downcast(aOther).reset();
179 }
180 constexpr Maybe_CopyMove_Enabler& operator=(Maybe_CopyMove_Enabler&& aOther) {
181 downcast(aOther).reset();
182 return *this;
183 }
184
185 private:
186 MOZ_MAYBE_DOWNCAST()
187};
188
189template <typename T>
190class Maybe_CopyMove_Enabler<T, false, true, true> {
191 public:
192 Maybe_CopyMove_Enabler() = default;
193
194 MOZ_MAYBE_COPY_OPS()
195 MOZ_MAYBE_MOVE_OPS()
196
197 private:
198 MOZ_MAYBE_DOWNCAST()
199};
200
201template <typename T>
202class Maybe_CopyMove_Enabler<T, false, false, true> {
203 public:
204 Maybe_CopyMove_Enabler() = default;
205
206 Maybe_CopyMove_Enabler(const Maybe_CopyMove_Enabler&) = delete;
207 Maybe_CopyMove_Enabler& operator=(const Maybe_CopyMove_Enabler&) = delete;
208 MOZ_MAYBE_MOVE_OPS()
209
210 private:
211 MOZ_MAYBE_DOWNCAST()
212};
213
214template <typename T>
215class Maybe_CopyMove_Enabler<T, false, true, false> {
216 public:
217 Maybe_CopyMove_Enabler() = default;
218
219 MOZ_MAYBE_COPY_OPS()
220 Maybe_CopyMove_Enabler(Maybe_CopyMove_Enabler&&) = delete;
221 Maybe_CopyMove_Enabler& operator=(Maybe_CopyMove_Enabler&&) = delete;
222
223 private:
224 MOZ_MAYBE_DOWNCAST()
225};
226
227template <typename T, bool TriviallyDestructibleAndCopyable>
228class Maybe_CopyMove_Enabler<T, TriviallyDestructibleAndCopyable, false,
229 false> {
230 public:
231 Maybe_CopyMove_Enabler() = default;
232
233 Maybe_CopyMove_Enabler(const Maybe_CopyMove_Enabler&) = delete;
234 Maybe_CopyMove_Enabler& operator=(const Maybe_CopyMove_Enabler&) = delete;
235 Maybe_CopyMove_Enabler(Maybe_CopyMove_Enabler&&) = delete;
236 Maybe_CopyMove_Enabler& operator=(Maybe_CopyMove_Enabler&&) = delete;
237};
238
239#undef MOZ_MAYBE_COPY_OPS
240#undef MOZ_MAYBE_MOVE_OPS
241#undef MOZ_MAYBE_DOWNCAST
242
243template <typename T, bool TriviallyDestructibleAndCopyable =
244 IsTriviallyDestructibleAndCopyable<T>>
245struct MaybeStorage;
246
247template <typename T>
248struct MaybeStorage<T, false> : MaybeStorageBase<T> {
249 protected:
250 char mIsSome = false; // not bool -- guarantees minimal space consumption
251
252 MaybeStorage() = default;
253 explicit MaybeStorage(const T& aVal)
254 : MaybeStorageBase<T>{aVal}, mIsSome{true} {}
255 explicit MaybeStorage(T&& aVal)
256 : MaybeStorageBase<T>{std::move(aVal)}, mIsSome{true} {}
257
258 template <typename... Args>
259 explicit MaybeStorage(std::in_place_t, Args&&... aArgs)
260 : MaybeStorageBase<T>{std::in_place, std::forward<Args>(aArgs)...},
261 mIsSome{true} {}
262
263 public:
264 // Copy and move operations are no-ops, since copying is moving is implemented
265 // by Maybe_CopyMove_Enabler.
266
267 MaybeStorage(const MaybeStorage&) : MaybeStorageBase<T>{} {}
268 MaybeStorage& operator=(const MaybeStorage&) { return *this; }
269 MaybeStorage(MaybeStorage&&) : MaybeStorageBase<T>{} {}
270 MaybeStorage& operator=(MaybeStorage&&) { return *this; }
271
272 ~MaybeStorage() {
273 if (mIsSome
12.1
Field 'mIsSome' is 1
12.1
Field 'mIsSome' is 1
12.1
Field 'mIsSome' is 1
12.1
Field 'mIsSome' is 1
12.1
Field 'mIsSome' is 1
12.1
Field 'mIsSome' is 1
12.1
Field 'mIsSome' is 1
) {
13
Taking true branch
274 this->addr()->T::~T();
14
Calling implicit destructor for 'ShortestPaths'
15
Calling implicit destructor for 'HashMap<JS::ubi::Node, mozilla::Vector<mozilla::UniquePtr<JS::ubi::BackEdge, JS::DeletePolicy<JS::ubi::BackEdge>>, 0, js::SystemAllocPolicy>, mozilla::DefaultHasher<JS::ubi::Node>, js::SystemAllocPolicy>'
16
Calling '~HashTable'
28
Returning from '~HashTable'
29
Returning from destructor for 'HashMap<JS::ubi::Node, mozilla::Vector<mozilla::UniquePtr<JS::ubi::BackEdge, JS::DeletePolicy<JS::ubi::BackEdge>>, 0, js::SystemAllocPolicy>, mozilla::DefaultHasher<JS::ubi::Node>, js::SystemAllocPolicy>'
30
Returning; memory was released
275 }
276 }
31
Calling implicit destructor for 'MaybeStorageBase<JS::ubi::ShortestPaths, false>'
32
Calling '~Union'
277};
278
279template <typename T>
280struct MaybeStorage<T, true> : MaybeStorageBase<T> {
281 protected:
282 char mIsSome = false; // not bool -- guarantees minimal space consumption
283
284 constexpr MaybeStorage() = default;
285 constexpr explicit MaybeStorage(const T& aVal)
286 : MaybeStorageBase<T>{aVal}, mIsSome{true} {}
287 constexpr explicit MaybeStorage(T&& aVal)
288 : MaybeStorageBase<T>{std::move(aVal)}, mIsSome{true} {}
289
290 template <typename... Args>
291 constexpr explicit MaybeStorage(std::in_place_t, Args&&... aArgs)
292 : MaybeStorageBase<T>{std::in_place, std::forward<Args>(aArgs)...},
293 mIsSome{true} {}
294};
295
296template <typename T>
297struct IsMaybeImpl : std::false_type {};
298
299template <typename T>
300struct IsMaybeImpl<Maybe<T>> : std::true_type {};
301
302template <typename T>
303using IsMaybe = IsMaybeImpl<std::decay_t<T>>;
304
305} // namespace detail
306
307template <typename T, typename U = typename std::remove_cv<
308 typename std::remove_reference<T>::type>::type>
309constexpr Maybe<U> Some(T&& aValue);
310
311/*
312 * Maybe is a container class which contains either zero or one elements. It
313 * serves two roles. It can represent values which are *semantically* optional,
314 * augmenting a type with an explicit 'Nothing' value. In this role, it provides
315 * methods that make it easy to work with values that may be missing, along with
316 * equality and comparison operators so that Maybe values can be stored in
317 * containers. Maybe values can be constructed conveniently in expressions using
318 * type inference, as follows:
319 *
320 * void doSomething(Maybe<Foo> aFoo) {
321 * if (aFoo) // Make sure that aFoo contains a value...
322 * aFoo->takeAction(); // and then use |aFoo->| to access it.
323 * } // |*aFoo| also works!
324 *
325 * doSomething(Nothing()); // Passes a Maybe<Foo> containing no value.
326 * doSomething(Some(Foo(100))); // Passes a Maybe<Foo> containing |Foo(100)|.
327 *
328 * You'll note that it's important to check whether a Maybe contains a value
329 * before using it, using conversion to bool, |isSome()|, or |isNothing()|. You
330 * can avoid these checks, and sometimes write more readable code, using
331 * |valueOr()|, |ptrOr()|, and |refOr()|, which allow you to retrieve the value
332 * in the Maybe and provide a default for the 'Nothing' case. You can also use
333 * |apply()| to call a function only if the Maybe holds a value, and |map()| to
334 * transform the value in the Maybe, returning another Maybe with a possibly
335 * different type.
336 *
337 * Maybe's other role is to support lazily constructing objects without using
338 * dynamic storage. A Maybe directly contains storage for a value, but it's
339 * empty by default. |emplace()|, as mentioned above, can be used to construct a
340 * value in Maybe's storage. The value a Maybe contains can be destroyed by
341 * calling |reset()|; this will happen automatically if a Maybe is destroyed
342 * while holding a value.
343 *
344 * It's a common idiom in C++ to use a pointer as a 'Maybe' type, with a null
345 * value meaning 'Nothing' and any other value meaning 'Some'. You can convert
346 * from such a pointer to a Maybe value using 'ToMaybe()'.
347 *
348 * Maybe is inspired by similar types in the standard library of many other
349 * languages (e.g. Haskell's Maybe and Rust's Option). In the C++ world it's
350 * very similar to std::optional, which was proposed for C++14 and originated in
351 * Boost. The most important differences between Maybe and std::optional are:
352 *
353 * - std::optional<T> may be compared with T. We deliberately forbid that.
354 * - std::optional has |valueOr()|, equivalent to Maybe's |valueOr()|, but
355 * lacks corresponding methods for |refOr()| and |ptrOr()|.
356 * - std::optional lacks |map()| and |apply()|, making it less suitable for
357 * functional-style code.
358 * - std::optional lacks many convenience functions that Maybe has. Most
359 * unfortunately, it lacks equivalents of the type-inferred constructor
360 * functions |Some()| and |Nothing()|.
361 */
362template <class T>
363class MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS Maybe
364 : private detail::MaybeStorage<T>,
365 public detail::Maybe_CopyMove_Enabler<T> {
366 template <typename, bool, bool, bool>
367 friend class detail::Maybe_CopyMove_Enabler;
368
369 template <typename U, typename V>
370 friend constexpr Maybe<V> Some(U&& aValue);
371
372 struct SomeGuard {};
373
374 template <typename U>
375 constexpr Maybe(U&& aValue, SomeGuard)
376 : detail::MaybeStorage<T>{std::forward<U>(aValue)} {}
377
378 using detail::MaybeStorage<T>::mIsSome;
379 using detail::MaybeStorage<T>::mStorage;
380
381 void poisonData() { detail::MaybePoisoner<T>::poison(&mStorage.val); }
382
383 public:
384 using ValueType = T;
385
386 MOZ_ALLOW_TEMPORARY constexpr Maybe() = default;
387
388 MOZ_ALLOW_TEMPORARY MOZ_IMPLICIT constexpr Maybe(Nothing) : Maybe{} {}
389
390 template <typename... Args>
391 constexpr explicit Maybe(std::in_place_t, Args&&... aArgs)
392 : detail::MaybeStorage<T>{std::in_place, std::forward<Args>(aArgs)...} {}
393
394 /**
395 * Maybe<T> can be copy-constructed from a Maybe<U> if T is constructible from
396 * a const U&.
397 */
398 template <typename U,
399 std::enable_if_t<std::is_constructible_v<T, const U&>, bool> = true>
400 MOZ_IMPLICIT Maybe(const Maybe<U>& aOther) {
401 if (aOther.isSome()) {
402 emplace(*aOther);
403 }
404 }
405
406 template <typename U, std::enable_if_t<!std::is_constructible_v<T, const U&>,
407 bool> = true>
408 explicit Maybe(const Maybe<U>& aOther) = delete;
409
410 /**
411 * Maybe<T> can be move-constructed from a Maybe<U> if T is constructible from
412 * a U&&.
413 */
414 template <typename U,
415 std::enable_if_t<std::is_constructible_v<T, U&&>, bool> = true>
416 MOZ_IMPLICIT Maybe(Maybe<U>&& aOther) {
417 if (aOther.isSome()) {
418 emplace(std::move(*aOther));
419 aOther.reset();
420 }
421 }
422 template <typename U,
423 std::enable_if_t<!std::is_constructible_v<T, U&&>, bool> = true>
424 explicit Maybe(Maybe<U>&& aOther) = delete;
425
426 template <typename U,
427 std::enable_if_t<std::is_constructible_v<T, const U&>, bool> = true>
428 Maybe& operator=(const Maybe<U>& aOther) {
429 if (aOther.isSome()) {
430 if (mIsSome) {
431 ref() = aOther.ref();
432 } else {
433 emplace(*aOther);
434 }
435 } else {
436 reset();
437 }
438 return *this;
439 }
440
441 template <typename U, std::enable_if_t<!std::is_constructible_v<T, const U&>,
442 bool> = true>
443 Maybe& operator=(const Maybe<U>& aOther) = delete;
444
445 template <typename U,
446 std::enable_if_t<std::is_constructible_v<T, U&&>, bool> = true>
447 Maybe& operator=(Maybe<U>&& aOther) {
448 if (aOther.isSome()) {
449 if (mIsSome) {
450 ref() = std::move(aOther.ref());
451 } else {
452 emplace(std::move(*aOther));
453 }
454 aOther.reset();
455 } else {
456 reset();
457 }
458
459 return *this;
460 }
461
462 template <typename U,
463 std::enable_if_t<!std::is_constructible_v<T, U&&>, bool> = true>
464 Maybe& operator=(Maybe<U>&& aOther) = delete;
465
466 constexpr Maybe& operator=(Nothing) {
467 reset();
468 return *this;
469 }
470
471 /* Methods that check whether this Maybe contains a value */
472 constexpr explicit operator bool() const { return isSome(); }
473 constexpr bool isSome() const { return mIsSome; }
474 constexpr bool isNothing() const { return !mIsSome; }
475
476 /* Returns the contents of this Maybe<T> by value. Unsafe unless |isSome()|.
477 */
478 constexpr T value() const&;
479 constexpr T value() &&;
480 constexpr T value() const&&;
481
482 /**
483 * Move the contents of this Maybe<T> out of internal storage and return it
484 * without calling the destructor. The internal storage is also reset to
485 * avoid multiple calls. Unsafe unless |isSome()|.
486 */
487 constexpr T extract() {
488 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 488); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 488; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
489 T v = std::move(mStorage.val);
490 reset();
491 return v;
492 }
493
494 /**
495 * Returns the value (possibly |Nothing()|) by moving it out of this Maybe<T>
496 * and leaving |Nothing()| in its place.
497 */
498 Maybe<T> take() { return std::exchange(*this, Nothing()); }
499
500 /*
501 * Returns the contents of this Maybe<T> by value. If |isNothing()|, returns
502 * the default value provided.
503 *
504 * Note: If the value passed to aDefault is not the result of a trivial
505 * expression, but expensive to evaluate, e.g. |valueOr(ExpensiveFunction())|,
506 * use |valueOrFrom| instead, e.g.
507 * |valueOrFrom([arg] { return ExpensiveFunction(arg); })|. This ensures
508 * that the expensive expression is only evaluated when its result will
509 * actually be used.
510 */
511 template <typename V>
512 constexpr T valueOr(V&& aDefault) const {
513 if (isSome()) {
514 return ref();
515 }
516 return std::forward<V>(aDefault);
517 }
518
519 /*
520 * Returns the contents of this Maybe<T> by value. If |isNothing()|, returns
521 * the value returned from the function or functor provided.
522 */
523 template <typename F>
524 constexpr T valueOrFrom(F&& aFunc) const {
525 if (isSome()) {
526 return ref();
527 }
528 return aFunc();
529 }
530
531 /* Returns the contents of this Maybe<T> by pointer. Unsafe unless |isSome()|.
532 */
533 T* ptr();
534 constexpr const T* ptr() const;
535
536 /*
537 * Returns the contents of this Maybe<T> by pointer. If |isNothing()|,
538 * returns the default value provided.
539 */
540 T* ptrOr(T* aDefault) {
541 if (isSome()) {
542 return ptr();
543 }
544 return aDefault;
545 }
546
547 constexpr const T* ptrOr(const T* aDefault) const {
548 if (isSome()) {
549 return ptr();
550 }
551 return aDefault;
552 }
553
554 /*
555 * Returns the contents of this Maybe<T> by pointer. If |isNothing()|,
556 * returns the value returned from the function or functor provided.
557 */
558 template <typename F>
559 T* ptrOrFrom(F&& aFunc) {
560 if (isSome()) {
561 return ptr();
562 }
563 return aFunc();
564 }
565
566 template <typename F>
567 const T* ptrOrFrom(F&& aFunc) const {
568 if (isSome()) {
569 return ptr();
570 }
571 return aFunc();
572 }
573
574 constexpr T* operator->();
575 constexpr const T* operator->() const;
576
577 /* Returns the contents of this Maybe<T> by ref. Unsafe unless |isSome()|. */
578 constexpr T& ref() &;
579 constexpr const T& ref() const&;
580 constexpr T&& ref() &&;
581 constexpr const T&& ref() const&&;
582
583 /*
584 * Returns the contents of this Maybe<T> by ref. If |isNothing()|, returns
585 * the default value provided.
586 */
587 constexpr T& refOr(T& aDefault) {
588 if (isSome()) {
589 return ref();
590 }
591 return aDefault;
592 }
593
594 constexpr const T& refOr(const T& aDefault) const {
595 if (isSome()) {
596 return ref();
597 }
598 return aDefault;
599 }
600
601 /*
602 * Returns the contents of this Maybe<T> by ref. If |isNothing()|, returns the
603 * value returned from the function or functor provided.
604 */
605 template <typename F>
606 constexpr T& refOrFrom(F&& aFunc) {
607 if (isSome()) {
608 return ref();
609 }
610 return aFunc();
611 }
612
613 template <typename F>
614 constexpr const T& refOrFrom(F&& aFunc) const {
615 if (isSome()) {
616 return ref();
617 }
618 return aFunc();
619 }
620
621 constexpr T& operator*() &;
622 constexpr const T& operator*() const&;
623 constexpr T&& operator*() &&;
624 constexpr const T&& operator*() const&&;
625
626 /* If |isSome()|, runs the provided function or functor on the contents of
627 * this Maybe. */
628 template <typename Func>
629 constexpr Maybe& apply(Func&& aFunc) & {
630 if (isSome()) {
631 std::forward<Func>(aFunc)(ref());
632 }
633 return *this;
634 }
635
636 template <typename Func>
637 constexpr const Maybe& apply(Func&& aFunc) const& {
638 if (isSome()) {
639 std::forward<Func>(aFunc)(ref());
640 }
641 return *this;
642 }
643
644 template <typename Func>
645 constexpr Maybe& apply(Func&& aFunc) && {
646 if (isSome()) {
647 std::forward<Func>(aFunc)(extract());
648 }
649 return *this;
650 }
651
652 template <typename Func>
653 constexpr Maybe& apply(Func&& aFunc) const&& {
654 if (isSome()) {
655 std::forward<Func>(aFunc)(extract());
656 }
657 return *this;
658 }
659
660 /*
661 * If |isSome()|, runs the provided function and returns the result wrapped
662 * in a Maybe. If |isNothing()|, returns an empty Maybe value with the same
663 * value type as what the provided function would have returned.
664 */
665 template <typename Func>
666 constexpr auto map(Func&& aFunc) & {
667 if (isSome()) {
668 return Some(std::forward<Func>(aFunc)(ref()));
669 }
670 return Maybe<decltype(std::forward<Func>(aFunc)(ref()))>{};
671 }
672
673 template <typename Func>
674 constexpr auto map(Func&& aFunc) const& {
675 if (isSome()) {
676 return Some(std::forward<Func>(aFunc)(ref()));
677 }
678 return Maybe<decltype(std::forward<Func>(aFunc)(ref()))>{};
679 }
680
681 template <typename Func>
682 constexpr auto map(Func&& aFunc) && {
683 if (isSome()) {
684 return Some(std::forward<Func>(aFunc)(extract()));
685 }
686 return Maybe<decltype(std::forward<Func>(aFunc)(extract()))>{};
687 }
688
689 template <typename Func>
690 constexpr auto map(Func&& aFunc) const&& {
691 if (isSome()) {
692 return Some(std::forward<Func>(aFunc)(extract()));
693 }
694 return Maybe<decltype(std::forward<Func>(aFunc)(extract()))>{};
695 }
696
697 /*
698 * If |isSome()|, runs the provided function or functor on the contents of
699 * this Maybe and returns the result. Note that the provided function or
700 * functor must return a Maybe<U> of any type U.
701 * If |isNothing()|, returns an empty Maybe value with the same type as what
702 * the provided function would have returned.
703 */
704 template <typename Func>
705 constexpr auto andThen(Func&& aFunc) & {
706 static_assert(std::is_invocable_v<Func, T&>);
707 using U = std::invoke_result_t<Func, T&>;
708 static_assert(detail::IsMaybe<U>::value);
709 if (isSome()) {
710 return std::invoke(std::forward<Func>(aFunc), ref());
711 }
712 return std::remove_cv_t<std::remove_reference_t<U>>{};
713 }
714
715 template <typename Func>
716 constexpr auto andThen(Func&& aFunc) const& {
717 static_assert(std::is_invocable_v<Func, const T&>);
718 using U = std::invoke_result_t<Func, const T&>;
719 static_assert(detail::IsMaybe<U>::value);
720 if (isSome()) {
721 return std::invoke(std::forward<Func>(aFunc), ref());
722 }
723 return std::remove_cv_t<std::remove_reference_t<U>>{};
724 }
725
726 template <typename Func>
727 constexpr auto andThen(Func&& aFunc) && {
728 static_assert(std::is_invocable_v<Func, T&&>);
729 using U = std::invoke_result_t<Func, T&&>;
730 static_assert(detail::IsMaybe<U>::value);
731 if (isSome()) {
732 return std::invoke(std::forward<Func>(aFunc), extract());
733 }
734 return std::remove_cv_t<std::remove_reference_t<U>>{};
735 }
736
737 template <typename Func>
738 constexpr auto andThen(Func&& aFunc) const&& {
739 static_assert(std::is_invocable_v<Func, const T&&>);
740 using U = std::invoke_result_t<Func, const T&&>;
741 static_assert(detail::IsMaybe<U>::value);
742 if (isSome()) {
743 return std::invoke(std::forward<Func>(aFunc), extract());
744 }
745 return std::remove_cv_t<std::remove_reference_t<U>>{};
746 }
747
748 /*
749 * If |isNothing()|, runs the provided function or functor and returns its
750 * result. If |isSome()|, returns the contained value wrapped in a Maybe.
751 */
752 template <typename Func>
753 constexpr Maybe orElse(Func&& aFunc) & {
754 static_assert(std::is_invocable_v<Func>);
755 using U = std::invoke_result_t<Func>;
756 static_assert(
757 std::is_same_v<Maybe, std::remove_cv_t<std::remove_reference_t<U>>>);
758 if (isSome()) {
759 return *this;
760 }
761 return std::invoke(std::forward<Func>(aFunc));
762 }
763
764 template <typename Func>
765 constexpr Maybe orElse(Func&& aFunc) const& {
766 static_assert(std::is_invocable_v<Func>);
767 using U = std::invoke_result_t<Func>;
768 static_assert(
769 std::is_same_v<Maybe, std::remove_cv_t<std::remove_reference_t<U>>>);
770 if (isSome()) {
771 return *this;
772 }
773 return std::invoke(std::forward<Func>(aFunc));
774 }
775
776 template <typename Func>
777 constexpr Maybe orElse(Func&& aFunc) && {
778 static_assert(std::is_invocable_v<Func>);
779 using U = std::invoke_result_t<Func>;
780 static_assert(
781 std::is_same_v<Maybe, std::remove_cv_t<std::remove_reference_t<U>>>);
782 if (isSome()) {
783 return std::move(*this);
784 }
785 return std::invoke(std::forward<Func>(aFunc));
786 }
787
788 template <typename Func>
789 constexpr Maybe orElse(Func&& aFunc) const&& {
790 static_assert(std::is_invocable_v<Func>);
791 using U = std::invoke_result_t<Func>;
792 static_assert(
793 std::is_same_v<Maybe, std::remove_cv_t<std::remove_reference_t<U>>>);
794 if (isSome()) {
795 return std::move(*this);
796 }
797 return std::invoke(std::forward<Func>(aFunc));
798 }
799
800 /* If |isSome()|, empties this Maybe and destroys its contents. */
801 constexpr void reset() {
802 if (isSome()) {
803 if constexpr (!std::is_trivially_destructible_v<T>) {
804 /*
805 * Static analyzer gets confused if we have Maybe<MutexAutoLock>,
806 * so we suppress thread-safety warnings here
807 */
808 MOZ_PUSH_IGNORE_THREAD_SAFETYGCC diagnostic push GCC diagnostic ignored "-Wthread-safety"
809 ref().T::~T();
810 MOZ_POP_THREAD_SAFETYGCC diagnostic pop
811 poisonData();
812 }
813 mIsSome = false;
814 }
815 }
816
817 /*
818 * Constructs a T value in-place in this empty Maybe<T>'s storage. The
819 * arguments to |emplace()| are the parameters to T's constructor.
820 */
821 template <typename... Args>
822 constexpr void emplace(Args&&... aArgs);
823
824 template <typename U>
825 constexpr std::enable_if_t<std::is_same_v<T, U> &&
826 std::is_copy_constructible_v<U> &&
827 !std::is_move_constructible_v<U>>
828 emplace(U&& aArgs) {
829 emplace(aArgs);
830 }
831
832 friend std::ostream& operator<<(std::ostream& aStream,
833 const Maybe<T>& aMaybe) {
834 if (aMaybe) {
835 aStream << aMaybe.ref();
836 } else {
837 aStream << "<Nothing>";
838 }
839 return aStream;
840 }
841};
842
843template <typename T>
844class Maybe<T&> {
845 public:
846 constexpr Maybe() = default;
847 constexpr MOZ_IMPLICIT Maybe(Nothing) {}
848
849 void emplace(T& aRef) { mValue = &aRef; }
850
851 /* Methods that check whether this Maybe contains a value */
852 constexpr explicit operator bool() const { return isSome(); }
853 constexpr bool isSome() const { return mValue; }
854 constexpr bool isNothing() const { return !mValue; }
855
856 T& ref() const {
857 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 857); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 857; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
858 return *mValue;
859 }
860
861 T* operator->() const { return &ref(); }
862 T& operator*() const { return ref(); }
863
864 // Deliberately not defining value and ptr accessors, as these may be
865 // confusing on a reference-typed Maybe.
866
867 // XXX Should we define refOr?
868
869 void reset() { mValue = nullptr; }
870
871 template <typename Func>
872 const Maybe& apply(Func&& aFunc) const {
873 if (isSome()) {
874 std::forward<Func>(aFunc)(ref());
875 }
876 return *this;
877 }
878
879 template <typename Func>
880 auto map(Func&& aFunc) const {
881 Maybe<decltype(std::forward<Func>(aFunc)(ref()))> val;
882 if (isSome()) {
883 val.emplace(std::forward<Func>(aFunc)(ref()));
884 }
885 return val;
886 }
887
888 template <typename Func>
889 constexpr auto andThen(Func&& aFunc) const {
890 static_assert(std::is_invocable_v<Func, T&>);
891 using U = std::invoke_result_t<Func, T&>;
892 static_assert(detail::IsMaybe<U>::value);
893 if (isSome()) {
894 return std::invoke(std::forward<Func>(aFunc), ref());
895 }
896 return std::remove_cv_t<std::remove_reference_t<U>>{};
897 }
898
899 template <typename Func>
900 constexpr Maybe orElse(Func&& aFunc) const {
901 static_assert(std::is_invocable_v<Func>);
902 using U = std::invoke_result_t<Func>;
903 static_assert(
904 std::is_same_v<Maybe, std::remove_cv_t<std::remove_reference_t<U>>>);
905 if (isSome()) {
906 return *this;
907 }
908 return std::invoke(std::forward<Func>(aFunc));
909 }
910
911 bool refEquals(const Maybe<T&>& aOther) const {
912 return mValue == aOther.mValue;
913 }
914
915 bool refEquals(const T& aOther) const { return mValue == &aOther; }
916
917 private:
918 T* mValue = nullptr;
919};
920
921template <typename T>
922constexpr T Maybe<T>::value() const& {
923 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 923); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 923; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
924 return ref();
925}
926
927template <typename T>
928constexpr T Maybe<T>::value() && {
929 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 929); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 929; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
930 return std::move(ref());
931}
932
933template <typename T>
934constexpr T Maybe<T>::value() const&& {
935 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 935); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 935; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
936 return std::move(ref());
937}
938
939template <typename T>
940T* Maybe<T>::ptr() {
941 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 941); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 941; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
942 return &ref();
943}
944
945template <typename T>
946constexpr const T* Maybe<T>::ptr() const {
947 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 947); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 947; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
948 return &ref();
949}
950
951template <typename T>
952constexpr T* Maybe<T>::operator->() {
953 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 953); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 953; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
954 return ptr();
955}
956
957template <typename T>
958constexpr const T* Maybe<T>::operator->() const {
959 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 959); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 959; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
960 return ptr();
961}
962
963template <typename T>
964constexpr T& Maybe<T>::ref() & {
965 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 965); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 965; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
966 return mStorage.val;
967}
968
969template <typename T>
970constexpr const T& Maybe<T>::ref() const& {
971 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 971); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 971; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
972 return mStorage.val;
973}
974
975template <typename T>
976constexpr T&& Maybe<T>::ref() && {
977 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 977); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 977; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
978 return std::move(mStorage.val);
979}
980
981template <typename T>
982constexpr const T&& Maybe<T>::ref() const&& {
983 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 983); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 983; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
984 return std::move(mStorage.val);
985}
986
987template <typename T>
988constexpr T& Maybe<T>::operator*() & {
989 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 989); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 989; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
990 return ref();
991}
992
993template <typename T>
994constexpr const T& Maybe<T>::operator*() const& {
995 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 995); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 995; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
996 return ref();
997}
998
999template <typename T>
1000constexpr T&& Maybe<T>::operator*() && {
1001 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 1001); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 1001; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1002 return std::move(ref());
1003}
1004
1005template <typename T>
1006constexpr const T&& Maybe<T>::operator*() const&& {
1007 MOZ_RELEASE_ASSERT(isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 1007); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "isSome()"
")"); do { *((volatile int*)__null) = 1007; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1008 return std::move(ref());
1009}
1010
1011template <typename T>
1012template <typename... Args>
1013constexpr void Maybe<T>::emplace(Args&&... aArgs) {
1014 MOZ_RELEASE_ASSERT(!isSome())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!isSome())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!isSome()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("!isSome()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/Maybe.h"
, 1014); AnnotateMozCrashReason("MOZ_RELEASE_ASSERT" "(" "!isSome()"
")"); do { *((volatile int*)__null) = 1014; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1015 ::new (KnownNotNull, &mStorage.val) T(std::forward<Args>(aArgs)...);
1016 mIsSome = true;
1017}
1018
1019/*
1020 * Some() creates a Maybe<T> value containing the provided T value. If T has a
1021 * move constructor, it's used to make this as efficient as possible.
1022 *
1023 * Some() selects the type of Maybe it returns by removing any const, volatile,
1024 * or reference qualifiers from the type of the value you pass to it. This gives
1025 * it more intuitive behavior when used in expressions, but it also means that
1026 * if you need to construct a Maybe value that holds a const, volatile, or
1027 * reference value, you need to use emplace() instead.
1028 */
1029template <typename T, typename U>
1030constexpr Maybe<U> Some(T&& aValue) {
1031 return {std::forward<T>(aValue), typename Maybe<U>::SomeGuard{}};
1032}
1033
1034template <typename T>
1035constexpr Maybe<T&> SomeRef(T& aValue) {
1036 Maybe<T&> value;
1037 value.emplace(aValue);
1038 return value;
1039}
1040
1041template <typename T>
1042constexpr Maybe<T&> ToMaybeRef(T* const aPtr) {
1043 return aPtr ? SomeRef(*aPtr) : Nothing{};
1044}
1045
1046template <typename T>
1047Maybe<std::remove_cv_t<std::remove_reference_t<T>>> ToMaybe(T* aPtr) {
1048 if (aPtr) {
1049 return Some(*aPtr);
1050 }
1051 return Nothing();
1052}
1053
1054/*
1055 * Two Maybe<T> values are equal if
1056 * - both are Nothing, or
1057 * - both are Some, and the values they contain are equal.
1058 */
1059template <typename T>
1060constexpr bool operator==(const Maybe<T>& aLHS, const Maybe<T>& aRHS) {
1061 static_assert(!std::is_reference_v<T>,
1062 "operator== is not defined for Maybe<T&>, compare values or "
1063 "addresses explicitly instead");
1064 if (aLHS.isNothing() != aRHS.isNothing()) {
1065 return false;
1066 }
1067 return aLHS.isNothing() || *aLHS == *aRHS;
1068}
1069
1070template <typename T>
1071constexpr bool operator!=(const Maybe<T>& aLHS, const Maybe<T>& aRHS) {
1072 return !(aLHS == aRHS);
1073}
1074
1075/*
1076 * We support comparison to Nothing to allow reasonable expressions like:
1077 * if (maybeValue == Nothing()) { ... }
1078 */
1079template <typename T>
1080constexpr bool operator==(const Maybe<T>& aLHS, const Nothing& aRHS) {
1081 return aLHS.isNothing();
1082}
1083
1084template <typename T>
1085constexpr bool operator!=(const Maybe<T>& aLHS, const Nothing& aRHS) {
1086 return !(aLHS == aRHS);
1087}
1088
1089template <typename T>
1090constexpr bool operator==(const Nothing& aLHS, const Maybe<T>& aRHS) {
1091 return aRHS.isNothing();
1092}
1093
1094template <typename T>
1095constexpr bool operator!=(const Nothing& aLHS, const Maybe<T>& aRHS) {
1096 return !(aLHS == aRHS);
1097}
1098
1099/*
1100 * Maybe<T> values are ordered in the same way T values are ordered, except that
1101 * Nothing comes before anything else.
1102 */
1103template <typename T>
1104constexpr bool operator<(const Maybe<T>& aLHS, const Maybe<T>& aRHS) {
1105 if (aLHS.isNothing()) {
1106 return aRHS.isSome();
1107 }
1108 if (aRHS.isNothing()) {
1109 return false;
1110 }
1111 return *aLHS < *aRHS;
1112}
1113
1114template <typename T>
1115constexpr bool operator>(const Maybe<T>& aLHS, const Maybe<T>& aRHS) {
1116 return !(aLHS < aRHS || aLHS == aRHS);
1117}
1118
1119template <typename T>
1120constexpr bool operator<=(const Maybe<T>& aLHS, const Maybe<T>& aRHS) {
1121 return aLHS < aRHS || aLHS == aRHS;
1122}
1123
1124template <typename T>
1125constexpr bool operator>=(const Maybe<T>& aLHS, const Maybe<T>& aRHS) {
1126 return !(aLHS < aRHS);
1127}
1128
1129template <typename T>
1130inline void ImplCycleCollectionTraverse(
1131 nsCycleCollectionTraversalCallback& aCallback, mozilla::Maybe<T>& aField,
1132 const char* aName, uint32_t aFlags = 0) {
1133 if (aField) {
1134 ImplCycleCollectionTraverse(aCallback, aField.ref(), aName, aFlags);
1135 }
1136}
1137
1138template <typename T>
1139inline void ImplCycleCollectionUnlink(mozilla::Maybe<T>& aField) {
1140 if (aField) {
1141 ImplCycleCollectionUnlink(aField.ref());
1142 }
1143}
1144
1145} // namespace mozilla
1146
1147#endif /* mozilla_Maybe_h */

/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h

1/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
2 * vim: set ts=8 sts=2 et sw=2 tw=80:
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7#ifndef js_UbiNodeShortestPaths_h
8#define js_UbiNodeShortestPaths_h
9
10#include "mozilla/CheckedInt.h"
11#include "mozilla/Maybe.h"
12
13#include <utility>
14
15#include "js/AllocPolicy.h"
16#include "js/GCAPI.h"
17#include "js/UbiNode.h"
18#include "js/UbiNodeBreadthFirst.h"
19#include "js/UniquePtr.h"
20
21namespace JS {
22namespace ubi {
23
24/**
25 * A back edge along a path in the heap graph.
26 */
27struct JS_PUBLIC_API BackEdge {
28 private:
29 Node predecessor_;
30 EdgeName name_;
31
32 public:
33 using Ptr = js::UniquePtr<BackEdge>;
34
35 BackEdge() : predecessor_(), name_(nullptr) {}
36
37 [[nodiscard]] bool init(const Node& predecessor, Edge& edge) {
38 MOZ_ASSERT(!predecessor_)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!predecessor_)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!predecessor_))), 0))) { do {
} while (false); MOZ_ReportAssertionFailure("!predecessor_",
"/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 38); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!predecessor_"
")"); do { *((volatile int*)__null) = 38; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
39 MOZ_ASSERT(!name_)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!name_)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(!name_))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("!name_", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 39); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!name_" ")");
do { *((volatile int*)__null) = 39; __attribute__((nomerge))
::abort(); } while (false); } } while (false)
;
40
41 predecessor_ = predecessor;
42 name_ = std::move(edge.name);
43 return true;
44 }
45
46 BackEdge(const BackEdge&) = delete;
47 BackEdge& operator=(const BackEdge&) = delete;
48
49 BackEdge(BackEdge&& rhs)
50 : predecessor_(rhs.predecessor_), name_(std::move(rhs.name_)) {
51 MOZ_ASSERT(&rhs != this)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(&rhs != this)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(&rhs != this))), 0))) { do
{ } while (false); MOZ_ReportAssertionFailure("&rhs != this"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 51); AnnotateMozCrashReason("MOZ_ASSERT" "(" "&rhs != this"
")"); do { *((volatile int*)__null) = 51; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
52 }
53
54 BackEdge& operator=(BackEdge&& rhs) {
55 this->~BackEdge();
56 new (this) BackEdge(std::move(rhs));
57 return *this;
58 }
59
60 Ptr clone() const;
61
62 const EdgeName& name() const { return name_; }
63 EdgeName& name() { return name_; }
64
65 const JS::ubi::Node& predecessor() const { return predecessor_; }
66};
67
68/**
69 * A path is a series of back edges from which we discovered a target node.
70 */
71using Path = JS::ubi::Vector<BackEdge*>;
72
73/**
74 * The `JS::ubi::ShortestPaths` type represents a collection of up to N shortest
75 * retaining paths for each of a target set of nodes, starting from the same
76 * root node.
77 */
78struct JS_PUBLIC_API ShortestPaths {
79 private:
80 // Types, type aliases, and data members.
81
82 using BackEdgeVector = JS::ubi::Vector<BackEdge::Ptr>;
83 using NodeToBackEdgeVectorMap =
84 js::HashMap<Node, BackEdgeVector, js::DefaultHasher<Node>,
85 js::SystemAllocPolicy>;
86
87 struct Handler;
88 using Traversal = BreadthFirst<Handler>;
89
90 /**
91 * A `JS::ubi::BreadthFirst` traversal handler that records back edges for
92 * how we reached each node, allowing us to reconstruct the shortest
93 * retaining paths after the traversal.
94 */
95 struct Handler {
96 using NodeData = BackEdge;
97
98 ShortestPaths& shortestPaths;
99 size_t totalMaxPathsToRecord;
100 size_t totalPathsRecorded;
101
102 explicit Handler(ShortestPaths& shortestPaths)
103 : shortestPaths(shortestPaths),
104 totalMaxPathsToRecord(shortestPaths.targets_.count() *
105 shortestPaths.maxNumPaths_),
106 totalPathsRecorded(0) {}
107
108 bool operator()(Traversal& traversal, const JS::ubi::Node& origin,
109 JS::ubi::Edge& edge, BackEdge* back, bool first) {
110 MOZ_ASSERT(back)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(back)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(back))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("back", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 110); AnnotateMozCrashReason("MOZ_ASSERT" "(" "back" ")"); do
{ *((volatile int*)__null) = 110; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
111 MOZ_ASSERT(origin == shortestPaths.root_ ||do { static_assert( mozilla::detail::AssertionConditionType<
decltype(origin == shortestPaths.root_ || traversal.visited.has
(origin))>::isValid, "invalid assertion condition"); if ((
__builtin_expect(!!(!(!!(origin == shortestPaths.root_ || traversal
.visited.has(origin)))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("origin == shortestPaths.root_ || traversal.visited.has(origin)"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 112); AnnotateMozCrashReason("MOZ_ASSERT" "(" "origin == shortestPaths.root_ || traversal.visited.has(origin)"
")"); do { *((volatile int*)__null) = 112; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
112 traversal.visited.has(origin))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(origin == shortestPaths.root_ || traversal.visited.has
(origin))>::isValid, "invalid assertion condition"); if ((
__builtin_expect(!!(!(!!(origin == shortestPaths.root_ || traversal
.visited.has(origin)))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("origin == shortestPaths.root_ || traversal.visited.has(origin)"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 112); AnnotateMozCrashReason("MOZ_ASSERT" "(" "origin == shortestPaths.root_ || traversal.visited.has(origin)"
")"); do { *((volatile int*)__null) = 112; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
113 MOZ_ASSERT(totalPathsRecorded < totalMaxPathsToRecord)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(totalPathsRecorded < totalMaxPathsToRecord)>::
isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!(totalPathsRecorded < totalMaxPathsToRecord))), 0)
)) { do { } while (false); MOZ_ReportAssertionFailure("totalPathsRecorded < totalMaxPathsToRecord"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 113); AnnotateMozCrashReason("MOZ_ASSERT" "(" "totalPathsRecorded < totalMaxPathsToRecord"
")"); do { *((volatile int*)__null) = 113; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
114
115 if (first && !back->init(origin, edge)) {
116 return false;
117 }
118
119 if (!shortestPaths.targets_.has(edge.referent)) {
120 return true;
121 }
122
123 // If `first` is true, then we moved the edge's name into `back` in
124 // the above call to `init`. So clone that back edge to get the
125 // correct edge name. If `first` is not true, then our edge name is
126 // still in `edge`. This accounts for the asymmetry between
127 // `back->clone()` in the first branch, and the `init` call in the
128 // second branch.
129
130 if (first) {
131 BackEdgeVector paths;
132 if (!paths.reserve(shortestPaths.maxNumPaths_)) {
133 return false;
134 }
135 auto cloned = back->clone();
136 if (!cloned) {
137 return false;
138 }
139 paths.infallibleAppend(std::move(cloned));
140 if (!shortestPaths.paths_.putNew(edge.referent, std::move(paths))) {
141 return false;
142 }
143 totalPathsRecorded++;
144 } else {
145 auto ptr = shortestPaths.paths_.lookup(edge.referent);
146 MOZ_ASSERT(ptr,do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr" " (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 151); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ") (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")"); do { *((volatile int*)__null
) = 151; __attribute__((nomerge)) ::abort(); } while (false);
} } while (false)
147 "This isn't the first time we have seen the target node "do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr" " (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 151); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ") (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")"); do { *((volatile int*)__null
) = 151; __attribute__((nomerge)) ::abort(); } while (false);
} } while (false)
148 "`edge.referent`. "do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr" " (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 151); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ") (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")"); do { *((volatile int*)__null
) = 151; __attribute__((nomerge)) ::abort(); } while (false);
} } while (false)
149 "We should have inserted it into shortestPaths.paths_ the "do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr" " (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 151); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ") (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")"); do { *((volatile int*)__null
) = 151; __attribute__((nomerge)) ::abort(); } while (false);
} } while (false)
150 "first time we "do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr" " (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 151); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ") (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")"); do { *((volatile int*)__null
) = 151; __attribute__((nomerge)) ::abort(); } while (false);
} } while (false)
151 "saw it.")do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(ptr))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("ptr" " (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 151); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr" ") (" "This isn't the first time we have seen the target node "
"`edge.referent`. " "We should have inserted it into shortestPaths.paths_ the "
"first time we " "saw it." ")"); do { *((volatile int*)__null
) = 151; __attribute__((nomerge)) ::abort(); } while (false);
} } while (false)
;
152
153 if (ptr->value().length() < shortestPaths.maxNumPaths_) {
154 auto thisBackEdge = js::MakeUnique<BackEdge>();
155 if (!thisBackEdge || !thisBackEdge->init(origin, edge)) {
156 return false;
157 }
158 ptr->value().infallibleAppend(std::move(thisBackEdge));
159 totalPathsRecorded++;
160 }
161 }
162
163 MOZ_ASSERT(totalPathsRecorded <= totalMaxPathsToRecord)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(totalPathsRecorded <= totalMaxPathsToRecord)>::
isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!(totalPathsRecorded <= totalMaxPathsToRecord))), 0
))) { do { } while (false); MOZ_ReportAssertionFailure("totalPathsRecorded <= totalMaxPathsToRecord"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 163); AnnotateMozCrashReason("MOZ_ASSERT" "(" "totalPathsRecorded <= totalMaxPathsToRecord"
")"); do { *((volatile int*)__null) = 163; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
164 if (totalPathsRecorded == totalMaxPathsToRecord) {
165 traversal.stop();
166 }
167
168 return true;
169 }
170 };
171
172 // The maximum number of paths to record for each node.
173 uint32_t maxNumPaths_;
174
175 // The root node we are starting the search from.
176 Node root_;
177
178 // The set of nodes we are searching for paths to.
179 NodeSet targets_;
180
181 // The resulting paths.
182 NodeToBackEdgeVectorMap paths_;
183
184 // Need to keep alive the traversal's back edges so we can walk them later
185 // when the traversal is over when recreating the shortest paths.
186 Traversal::NodeMap backEdges_;
187
188 private:
189 // Private methods.
190
191 ShortestPaths(uint32_t maxNumPaths, const Node& root, NodeSet&& targets)
192 : maxNumPaths_(maxNumPaths),
193 root_(root),
194 targets_(std::move(targets)),
195 paths_(targets_.count()),
196 backEdges_() {
197 MOZ_ASSERT(maxNumPaths_ > 0)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(maxNumPaths_ > 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(maxNumPaths_ > 0))), 0)))
{ do { } while (false); MOZ_ReportAssertionFailure("maxNumPaths_ > 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 197); AnnotateMozCrashReason("MOZ_ASSERT" "(" "maxNumPaths_ > 0"
")"); do { *((volatile int*)__null) = 197; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
198 MOZ_ASSERT(root_)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(root_)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(root_))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("root_", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 198); AnnotateMozCrashReason("MOZ_ASSERT" "(" "root_" ")");
do { *((volatile int*)__null) = 198; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false)
;
199 }
200
201 public:
202 // Public methods.
203
204 ShortestPaths(ShortestPaths&& rhs)
205 : maxNumPaths_(rhs.maxNumPaths_),
206 root_(rhs.root_),
207 targets_(std::move(rhs.targets_)),
208 paths_(std::move(rhs.paths_)),
209 backEdges_(std::move(rhs.backEdges_)) {
210 MOZ_ASSERT(this != &rhs, "self-move is not allowed")do { static_assert( mozilla::detail::AssertionConditionType<
decltype(this != &rhs)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(this != &rhs))), 0))) { do
{ } while (false); MOZ_ReportAssertionFailure("this != &rhs"
" (" "self-move is not allowed" ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 210); AnnotateMozCrashReason("MOZ_ASSERT" "(" "this != &rhs"
") (" "self-move is not allowed" ")"); do { *((volatile int*
)__null) = 210; __attribute__((nomerge)) ::abort(); } while (
false); } } while (false)
;
211 }
212
213 ShortestPaths& operator=(ShortestPaths&& rhs) {
214 this->~ShortestPaths();
215 new (this) ShortestPaths(std::move(rhs));
216 return *this;
217 }
218
219 ShortestPaths(const ShortestPaths&) = delete;
220 ShortestPaths& operator=(const ShortestPaths&) = delete;
221
222 /**
223 * Construct a new `JS::ubi::ShortestPaths`, finding up to `maxNumPaths`
224 * shortest retaining paths for each target node in `targets` starting from
225 * `root`.
226 *
227 * The resulting `ShortestPaths` instance must not outlive the
228 * `JS::ubi::Node` graph it was constructed from.
229 *
230 * - For `JS::ubi::Node` graphs backed by the live heap graph, this means
231 * that the `ShortestPaths`'s lifetime _must_ be contained within the
232 * scope of the provided `AutoCheckCannotGC` reference because a GC will
233 * invalidate the nodes.
234 *
235 * - For `JS::ubi::Node` graphs backed by some other offline structure
236 * provided by the embedder, the resulting `ShortestPaths`'s lifetime is
237 * bounded by that offline structure's lifetime.
238 *
239 * Returns `mozilla::Nothing()` on OOM failure. It is the caller's
240 * responsibility to handle and report the OOM.
241 */
242 static mozilla::Maybe<ShortestPaths> Create(JSContext* cx,
243 AutoCheckCannotGC& noGC,
244 uint32_t maxNumPaths,
245 const Node& root,
246 NodeSet&& targets) {
247 MOZ_ASSERT(targets.count() > 0)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(targets.count() > 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(targets.count() > 0))), 0
))) { do { } while (false); MOZ_ReportAssertionFailure("targets.count() > 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 247); AnnotateMozCrashReason("MOZ_ASSERT" "(" "targets.count() > 0"
")"); do { *((volatile int*)__null) = 247; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
248 MOZ_ASSERT(maxNumPaths > 0)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(maxNumPaths > 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(maxNumPaths > 0))), 0))) {
do { } while (false); MOZ_ReportAssertionFailure("maxNumPaths > 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 248); AnnotateMozCrashReason("MOZ_ASSERT" "(" "maxNumPaths > 0"
")"); do { *((volatile int*)__null) = 248; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
249
250 mozilla::CheckedInt<uint32_t> max = maxNumPaths;
251 max *= targets.count();
252 if (!max.isValid()) {
253 return mozilla::Nothing();
254 }
255
256 ShortestPaths paths(maxNumPaths, root, std::move(targets));
257
258 Handler handler(paths);
259 Traversal traversal(cx, handler, noGC);
260 traversal.wantNames = true;
261 if (!traversal.addStart(root) || !traversal.traverse()) {
262 return mozilla::Nothing();
263 }
264
265 // Take ownership of the back edges we created while traversing the
266 // graph so that we can follow them from `paths_` and don't
267 // use-after-free.
268 paths.backEdges_ = std::move(traversal.visited);
269
270 return mozilla::Some(std::move(paths));
271 }
272
273 /**
274 * Get an iterator over each target node we searched for retaining paths
275 * for. The returned iterator must not outlive the `ShortestPaths`
276 * instance.
277 */
278 NodeSet::Iterator targetIter() const { return targets_.iter(); }
279
280 /**
281 * Invoke the provided functor/lambda/callable once for each retaining path
282 * discovered for `target`. The `func` is passed a single `JS::ubi::Path&`
283 * argument, which contains each edge along the path ordered starting from
284 * the root and ending at the target, and must not outlive the scope of the
285 * call.
286 *
287 * Note that it is possible that we did not find any paths from the root to
288 * the given target, in which case `func` will not be invoked.
289 */
290 template <class Func>
291 [[nodiscard]] bool forEachPath(const Node& target, Func func) {
292 MOZ_ASSERT(targets_.has(target))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(targets_.has(target))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(targets_.has(target)))), 0))
) { do { } while (false); MOZ_ReportAssertionFailure("targets_.has(target)"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 292); AnnotateMozCrashReason("MOZ_ASSERT" "(" "targets_.has(target)"
")"); do { *((volatile int*)__null) = 292; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
293
294 auto ptr = paths_.lookup(target);
295
296 // We didn't find any paths to this target, so nothing to do here.
297 if (!ptr) {
298 return true;
299 }
300
301 MOZ_ASSERT(ptr->value().length() <= maxNumPaths_)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(ptr->value().length() <= maxNumPaths_)>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(ptr->value().length() <= maxNumPaths_))), 0))) { do {
} while (false); MOZ_ReportAssertionFailure("ptr->value().length() <= maxNumPaths_"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 301); AnnotateMozCrashReason("MOZ_ASSERT" "(" "ptr->value().length() <= maxNumPaths_"
")"); do { *((volatile int*)__null) = 301; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
302
303 Path path;
304 for (const auto& backEdge : ptr->value()) {
305 path.clear();
306
307 if (!path.append(backEdge.get())) {
308 return false;
309 }
310
311 Node here = backEdge->predecessor();
312 MOZ_ASSERT(here)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(here)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(here))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("here", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 312); AnnotateMozCrashReason("MOZ_ASSERT" "(" "here" ")"); do
{ *((volatile int*)__null) = 312; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
313
314 while (here != root_) {
315 auto p = backEdges_.lookup(here);
316 MOZ_ASSERT(p)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(p)>::isValid, "invalid assertion condition"); if (
(__builtin_expect(!!(!(!!(p))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("p", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 316); AnnotateMozCrashReason("MOZ_ASSERT" "(" "p" ")"); do {
*((volatile int*)__null) = 316; __attribute__((nomerge)) ::abort
(); } while (false); } } while (false)
;
317 if (!path.append(&p->value())) {
318 return false;
319 }
320 here = p->value().predecessor();
321 MOZ_ASSERT(here)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(here)>::isValid, "invalid assertion condition"); if
((__builtin_expect(!!(!(!!(here))), 0))) { do { } while (false
); MOZ_ReportAssertionFailure("here", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/js/UbiNodeShortestPaths.h"
, 321); AnnotateMozCrashReason("MOZ_ASSERT" "(" "here" ")"); do
{ *((volatile int*)__null) = 321; __attribute__((nomerge)) ::
abort(); } while (false); } } while (false)
;
322 }
323
324 path.reverse();
325
326 if (!func(path)) {
327 return false;
328 }
329 }
330
331 return true;
332 }
333};
334
335#ifdef DEBUG1
336// A helper function to dump the first `maxNumPaths` shortest retaining paths to
337// `node` from the GC roots. Useful when GC things you expect to have been
338// reclaimed by the collector haven't been!
339//
340// Usage:
341//
342// JSObject* foo = ...;
343// JS::ubi::dumpPaths(rt, JS::ubi::Node(foo));
344JS_PUBLIC_API void dumpPaths(JSRuntime* rt, Node node,
345 uint32_t maxNumPaths = 10);
346#endif
347
348} // namespace ubi
349} // namespace JS
350
351#endif // js_UbiNodeShortestPaths_h

/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h

1/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2/* vim: set ts=8 sts=2 et sw=2 tw=80: */
3/* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7//---------------------------------------------------------------------------
8// Overview
9//---------------------------------------------------------------------------
10//
11// This file defines HashMap<Key, Value> and HashSet<T>, hash tables that are
12// fast and have a nice API.
13//
14// Both hash tables have two optional template parameters.
15//
16// - HashPolicy. This defines the operations for hashing and matching keys. The
17// default HashPolicy is appropriate when both of the following two
18// conditions are true.
19//
20// - The key type stored in the table (|Key| for |HashMap<Key, Value>|, |T|
21// for |HashSet<T>|) is an integer, pointer, UniquePtr, float, or double.
22//
23// - The type used for lookups (|Lookup|) is the same as the key type. This
24// is usually the case, but not always.
25//
26// There is also a |CStringHasher| policy for |char*| keys. If your keys
27// don't match any of the above cases, you must provide your own hash policy;
28// see the "Hash Policy" section below.
29//
30// - AllocPolicy. This defines how allocations are done by the table.
31//
32// - |MallocAllocPolicy| is the default and is usually appropriate; note that
33// operations (such as insertions) that might cause allocations are
34// fallible and must be checked for OOM. These checks are enforced by the
35// use of [[nodiscard]].
36//
37// - |InfallibleAllocPolicy| is another possibility; it allows the
38// abovementioned OOM checks to be done with MOZ_ALWAYS_TRUE().
39//
40// Note that entry storage allocation is lazy, and not done until the first
41// lookupForAdd(), put(), or putNew() is performed.
42//
43// See AllocPolicy.h for more details.
44//
45// Documentation on how to use HashMap and HashSet, including examples, is
46// present within those classes. Search for "class HashMap" and "class
47// HashSet".
48//
49// Both HashMap and HashSet are implemented on top of a third class, HashTable.
50// You only need to look at HashTable if you want to understand the
51// implementation.
52//
53// How does mozilla::HashTable (this file) compare with PLDHashTable (and its
54// subclasses, such as nsTHashtable)?
55//
56// - mozilla::HashTable is a lot faster, largely because it uses templates
57// throughout *and* inlines everything. PLDHashTable inlines operations much
58// less aggressively, and also uses "virtual ops" for operations like hashing
59// and matching entries that require function calls.
60//
61// - Correspondingly, mozilla::HashTable use is likely to increase executable
62// size much more than PLDHashTable.
63//
64// - mozilla::HashTable has a nicer API, with a proper HashSet vs. HashMap
65// distinction.
66//
67// - mozilla::HashTable requires more explicit OOM checking. As mentioned
68// above, the use of |InfallibleAllocPolicy| can simplify things.
69//
70// - mozilla::HashTable has a default capacity on creation of 32 and a minimum
71// capacity of 4. PLDHashTable has a default capacity on creation of 8 and a
72// minimum capacity of 8.
73
74#ifndef mozilla_HashTable_h
75#define mozilla_HashTable_h
76
77#include <utility>
78#include <type_traits>
79
80#include "mozilla/AllocPolicy.h"
81#include "mozilla/Assertions.h"
82#include "mozilla/Attributes.h"
83#include "mozilla/Casting.h"
84#include "mozilla/HashFunctions.h"
85#include "mozilla/MathAlgorithms.h"
86#include "mozilla/Maybe.h"
87#include "mozilla/MemoryChecking.h"
88#include "mozilla/MemoryReporting.h"
89#include "mozilla/Opaque.h"
90#include "mozilla/OperatorNewExtensions.h"
91#include "mozilla/ReentrancyGuard.h"
92#include "mozilla/UniquePtr.h"
93#include "mozilla/WrappingOperations.h"
94
95namespace mozilla {
96
97template <class, class = void>
98struct DefaultHasher;
99
100template <class, class>
101class HashMapEntry;
102
103namespace detail {
104
105template <typename T>
106class HashTableEntry;
107
108template <class T, class HashPolicy, class AllocPolicy>
109class HashTable;
110
111} // namespace detail
112
113// The "generation" of a hash table is an opaque value indicating the state of
114// modification of the hash table through its lifetime. If the generation of
115// a hash table compares equal at times T1 and T2, then lookups in the hash
116// table, pointers to (or into) hash table entries, etc. at time T1 are valid
117// at time T2. If the generation compares unequal, these computations are all
118// invalid and must be performed again to be used.
119//
120// Generations are meaningfully comparable only with respect to a single hash
121// table. It's always nonsensical to compare the generation of distinct hash
122// tables H1 and H2.
123using Generation = Opaque<uint64_t>;
124
125//---------------------------------------------------------------------------
126// HashMap
127//---------------------------------------------------------------------------
128
129// HashMap is a fast hash-based map from keys to values.
130//
131// Template parameter requirements:
132// - Key/Value: movable, destructible, assignable.
133// - HashPolicy: see the "Hash Policy" section below.
134// - AllocPolicy: see AllocPolicy.h.
135//
136// Note:
137// - HashMap is not reentrant: Key/Value/HashPolicy/AllocPolicy members
138// called by HashMap must not call back into the same HashMap object.
139//
140template <class Key, class Value, class HashPolicy = DefaultHasher<Key>,
141 class AllocPolicy = MallocAllocPolicy>
142class HashMap {
143 // -- Implementation details -----------------------------------------------
144
145 // HashMap is not copyable or assignable.
146 HashMap(const HashMap& hm) = delete;
147 HashMap& operator=(const HashMap& hm) = delete;
148
149 using TableEntry = HashMapEntry<Key, Value>;
150
151 struct MapHashPolicy : HashPolicy {
152 using Base = HashPolicy;
153 using KeyType = Key;
154
155 static const Key& getKey(TableEntry& aEntry) { return aEntry.key(); }
156
157 static void setKey(TableEntry& aEntry, Key& aKey) {
158 HashPolicy::rekey(aEntry.mutableKey(), aKey);
159 }
160 };
161
162 using Impl = detail::HashTable<TableEntry, MapHashPolicy, AllocPolicy>;
163 Impl mImpl;
164
165 friend class Impl::Enum;
166
167 public:
168 using Lookup = typename HashPolicy::Lookup;
169 using Entry = TableEntry;
170
171 // -- Initialization -------------------------------------------------------
172
173 explicit HashMap(AllocPolicy aAllocPolicy = AllocPolicy(),
174 uint32_t aLen = Impl::sDefaultLen)
175 : mImpl(std::move(aAllocPolicy), aLen) {}
176
177 explicit HashMap(uint32_t aLen) : mImpl(AllocPolicy(), aLen) {}
178
179 // HashMap is movable.
180 HashMap(HashMap&& aRhs) = default;
181 HashMap& operator=(HashMap&& aRhs) = default;
182
183 // -- Status and sizing ----------------------------------------------------
184
185 // The map's current generation.
186 Generation generation() const { return mImpl.generation(); }
187
188 // Is the map empty?
189 bool empty() const { return mImpl.empty(); }
190
191 // Number of keys/values in the map.
192 uint32_t count() const { return mImpl.count(); }
193
194 // Number of key/value slots in the map. Note: resize will happen well before
195 // count() == capacity().
196 uint32_t capacity() const { return mImpl.capacity(); }
197
198 // The size of the map's entry storage, in bytes. If the keys/values contain
199 // pointers to other heap blocks, you must iterate over the map and measure
200 // them separately; hence the "shallow" prefix.
201 size_t shallowSizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
202 return mImpl.shallowSizeOfExcludingThis(aMallocSizeOf);
203 }
204 size_t shallowSizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
205 return aMallocSizeOf(this) +
206 mImpl.shallowSizeOfExcludingThis(aMallocSizeOf);
207 }
208
209 // Attempt to minimize the capacity(). If the table is empty, this will free
210 // the empty storage and upon regrowth it will be given the minimum capacity.
211 void compact() { mImpl.compact(); }
212
213 // Attempt to reserve enough space to fit at least |aLen| elements. This is
214 // total capacity, including elements already present. Does nothing if the
215 // map already has sufficient capacity.
216 [[nodiscard]] bool reserve(uint32_t aLen) { return mImpl.reserve(aLen); }
217
218 // -- Lookups --------------------------------------------------------------
219
220 // Does the map contain a key/value matching |aLookup|?
221 bool has(const Lookup& aLookup) const {
222 return mImpl.lookup(aLookup).found();
223 }
224
225 // Return a Ptr indicating whether a key/value matching |aLookup| is
226 // present in the map. E.g.:
227 //
228 // using HM = HashMap<int,char>;
229 // HM h;
230 // if (HM::Ptr p = h.lookup(3)) {
231 // assert(p->key() == 3);
232 // char val = p->value();
233 // }
234 //
235 using Ptr = typename Impl::Ptr;
236 MOZ_ALWAYS_INLINEinline Ptr lookup(const Lookup& aLookup) const {
237 return mImpl.lookup(aLookup);
238 }
239
240 // Like lookup(), but does not assert if two threads call it at the same
241 // time. Only use this method when none of the threads will modify the map.
242 MOZ_ALWAYS_INLINEinline Ptr readonlyThreadsafeLookup(const Lookup& aLookup) const {
243 return mImpl.readonlyThreadsafeLookup(aLookup);
244 }
245
246 // -- Insertions -----------------------------------------------------------
247
248 // Overwrite existing value with |aValue|, or add it if not present. Returns
249 // false on OOM.
250 template <typename KeyInput, typename ValueInput>
251 [[nodiscard]] bool put(KeyInput&& aKey, ValueInput&& aValue) {
252 return put(aKey, std::forward<KeyInput>(aKey),
253 std::forward<ValueInput>(aValue));
254 }
255
256 template <typename KeyInput, typename ValueInput>
257 [[nodiscard]] bool put(const Lookup& aLookup, KeyInput&& aKey,
258 ValueInput&& aValue) {
259 AddPtr p = lookupForAdd(aLookup);
260 if (p) {
261 p->value() = std::forward<ValueInput>(aValue);
262 return true;
263 }
264 return add(p, std::forward<KeyInput>(aKey),
265 std::forward<ValueInput>(aValue));
266 }
267
268 // Like put(), but slightly faster. Must only be used when the given key is
269 // not already present. (In debug builds, assertions check this.)
270 template <typename KeyInput, typename ValueInput>
271 [[nodiscard]] bool putNew(KeyInput&& aKey, ValueInput&& aValue) {
272 return mImpl.putNew(aKey, std::forward<KeyInput>(aKey),
273 std::forward<ValueInput>(aValue));
274 }
275
276 template <typename KeyInput, typename ValueInput>
277 [[nodiscard]] bool putNew(const Lookup& aLookup, KeyInput&& aKey,
278 ValueInput&& aValue) {
279 return mImpl.putNew(aLookup, std::forward<KeyInput>(aKey),
280 std::forward<ValueInput>(aValue));
281 }
282
283 // Like putNew(), but should be only used when the table is known to be big
284 // enough for the insertion, and hashing cannot fail. Typically this is used
285 // to populate an empty map with known-unique keys after reserving space with
286 // reserve(), e.g.
287 //
288 // using HM = HashMap<int,char>;
289 // HM h;
290 // if (!h.reserve(3)) {
291 // MOZ_CRASH("OOM");
292 // }
293 // h.putNewInfallible(1, 'a'); // unique key
294 // h.putNewInfallible(2, 'b'); // unique key
295 // h.putNewInfallible(3, 'c'); // unique key
296 //
297 template <typename KeyInput, typename ValueInput>
298 void putNewInfallible(KeyInput&& aKey, ValueInput&& aValue) {
299 mImpl.putNewInfallible(aKey, std::forward<KeyInput>(aKey),
300 std::forward<ValueInput>(aValue));
301 }
302
303 // Like |lookup(l)|, but on miss, |p = lookupForAdd(l)| allows efficient
304 // insertion of Key |k| (where |HashPolicy::match(k,l) == true|) using
305 // |add(p,k,v)|. After |add(p,k,v)|, |p| points to the new key/value. E.g.:
306 //
307 // using HM = HashMap<int,char>;
308 // HM h;
309 // HM::AddPtr p = h.lookupForAdd(3);
310 // if (!p) {
311 // if (!h.add(p, 3, 'a')) {
312 // return false;
313 // }
314 // }
315 // assert(p->key() == 3);
316 // char val = p->value();
317 //
318 // N.B. The caller must ensure that no mutating hash table operations occur
319 // between a pair of lookupForAdd() and add() calls. To avoid looking up the
320 // key a second time, the caller may use the more efficient relookupOrAdd()
321 // method. This method reuses part of the hashing computation to more
322 // efficiently insert the key if it has not been added. For example, a
323 // mutation-handling version of the previous example:
324 //
325 // HM::AddPtr p = h.lookupForAdd(3);
326 // if (!p) {
327 // call_that_may_mutate_h();
328 // if (!h.relookupOrAdd(p, 3, 'a')) {
329 // return false;
330 // }
331 // }
332 // assert(p->key() == 3);
333 // char val = p->value();
334 //
335 using AddPtr = typename Impl::AddPtr;
336 MOZ_ALWAYS_INLINEinline AddPtr lookupForAdd(const Lookup& aLookup) {
337 return mImpl.lookupForAdd(aLookup);
338 }
339
340 // Add a key/value. Returns false on OOM.
341 template <typename KeyInput, typename ValueInput>
342 [[nodiscard]] bool add(AddPtr& aPtr, KeyInput&& aKey, ValueInput&& aValue) {
343 return mImpl.add(aPtr, std::forward<KeyInput>(aKey),
344 std::forward<ValueInput>(aValue));
345 }
346
347 // See the comment above lookupForAdd() for details.
348 template <typename KeyInput, typename ValueInput>
349 [[nodiscard]] bool relookupOrAdd(AddPtr& aPtr, KeyInput&& aKey,
350 ValueInput&& aValue) {
351 return mImpl.relookupOrAdd(aPtr, aKey, std::forward<KeyInput>(aKey),
352 std::forward<ValueInput>(aValue));
353 }
354
355 // -- Removal --------------------------------------------------------------
356
357 // Lookup and remove the key/value matching |aLookup|, if present.
358 void remove(const Lookup& aLookup) {
359 if (Ptr p = lookup(aLookup)) {
360 remove(p);
361 }
362 }
363
364 // Remove a previously found key/value (assuming aPtr.found()). The map must
365 // not have been mutated in the interim.
366 void remove(Ptr aPtr) { mImpl.remove(aPtr); }
367
368 // Remove all keys/values without changing the capacity.
369 void clear() { mImpl.clear(); }
370
371 // Like clear() followed by compact().
372 void clearAndCompact() { mImpl.clearAndCompact(); }
373
374 // -- Rekeying -------------------------------------------------------------
375
376 // Infallibly rekey one entry, if necessary. Requires that template
377 // parameters Key and HashPolicy::Lookup are the same type.
378 void rekeyIfMoved(const Key& aOldKey, const Key& aNewKey) {
379 if (aOldKey != aNewKey) {
380 rekeyAs(aOldKey, aNewKey, aNewKey);
381 }
382 }
383
384 // Infallibly rekey one entry if present, and return whether that happened.
385 bool rekeyAs(const Lookup& aOldLookup, const Lookup& aNewLookup,
386 const Key& aNewKey) {
387 if (Ptr p = lookup(aOldLookup)) {
388 mImpl.rekeyAndMaybeRehash(p, aNewLookup, aNewKey);
389 return true;
390 }
391 return false;
392 }
393
394 // -- Iteration ------------------------------------------------------------
395
396 // |iter()| returns an Iterator:
397 //
398 // HashMap<int, char> h;
399 // for (auto iter = h.iter(); !iter.done(); iter.next()) {
400 // char c = iter.get().value();
401 // }
402 //
403 using Iterator = typename Impl::Iterator;
404 Iterator iter() const { return mImpl.iter(); }
405
406 // |modIter()| returns a ModIterator:
407 //
408 // HashMap<int, char> h;
409 // for (auto iter = h.modIter(); !iter.done(); iter.next()) {
410 // if (iter.get().value() == 'l') {
411 // iter.remove();
412 // }
413 // }
414 //
415 // Table resize may occur in ModIterator's destructor.
416 using ModIterator = typename Impl::ModIterator;
417 ModIterator modIter() { return mImpl.modIter(); }
418
419 // These are similar to Iterator/ModIterator/iter(), but use different
420 // terminology.
421 using Range = typename Impl::Range;
422 using Enum = typename Impl::Enum;
423 Range all() const { return mImpl.all(); }
424};
425
426//---------------------------------------------------------------------------
427// HashSet
428//---------------------------------------------------------------------------
429
430// HashSet is a fast hash-based set of values.
431//
432// Template parameter requirements:
433// - T: movable, destructible, assignable.
434// - HashPolicy: see the "Hash Policy" section below.
435// - AllocPolicy: see AllocPolicy.h
436//
437// Note:
438// - HashSet is not reentrant: T/HashPolicy/AllocPolicy members called by
439// HashSet must not call back into the same HashSet object.
440//
441template <class T, class HashPolicy = DefaultHasher<T>,
442 class AllocPolicy = MallocAllocPolicy>
443class HashSet {
444 // -- Implementation details -----------------------------------------------
445
446 // HashSet is not copyable or assignable.
447 HashSet(const HashSet& hs) = delete;
448 HashSet& operator=(const HashSet& hs) = delete;
449
450 struct SetHashPolicy : HashPolicy {
451 using Base = HashPolicy;
452 using KeyType = T;
453
454 static const KeyType& getKey(const T& aT) { return aT; }
455
456 static void setKey(T& aT, KeyType& aKey) { HashPolicy::rekey(aT, aKey); }
457 };
458
459 using Impl = detail::HashTable<const T, SetHashPolicy, AllocPolicy>;
460 Impl mImpl;
461
462 friend class Impl::Enum;
463
464 public:
465 using Lookup = typename HashPolicy::Lookup;
466 using Entry = T;
467
468 // -- Initialization -------------------------------------------------------
469
470 explicit HashSet(AllocPolicy aAllocPolicy = AllocPolicy(),
471 uint32_t aLen = Impl::sDefaultLen)
472 : mImpl(std::move(aAllocPolicy), aLen) {}
473
474 explicit HashSet(uint32_t aLen) : mImpl(AllocPolicy(), aLen) {}
475
476 // HashSet is movable.
477 HashSet(HashSet&& aRhs) = default;
478 HashSet& operator=(HashSet&& aRhs) = default;
479
480 // -- Status and sizing ----------------------------------------------------
481
482 // The set's current generation.
483 Generation generation() const { return mImpl.generation(); }
484
485 // Is the set empty?
486 bool empty() const { return mImpl.empty(); }
487
488 // Number of elements in the set.
489 uint32_t count() const { return mImpl.count(); }
490
491 // Number of element slots in the set. Note: resize will happen well before
492 // count() == capacity().
493 uint32_t capacity() const { return mImpl.capacity(); }
494
495 // The size of the set's entry storage, in bytes. If the elements contain
496 // pointers to other heap blocks, you must iterate over the set and measure
497 // them separately; hence the "shallow" prefix.
498 size_t shallowSizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
499 return mImpl.shallowSizeOfExcludingThis(aMallocSizeOf);
500 }
501 size_t shallowSizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
502 return aMallocSizeOf(this) +
503 mImpl.shallowSizeOfExcludingThis(aMallocSizeOf);
504 }
505
506 // Attempt to minimize the capacity(). If the table is empty, this will free
507 // the empty storage and upon regrowth it will be given the minimum capacity.
508 void compact() { mImpl.compact(); }
509
510 // Attempt to reserve enough space to fit at least |aLen| elements. This is
511 // total capacity, including elements already present. Does nothing if the
512 // map already has sufficient capacity.
513 [[nodiscard]] bool reserve(uint32_t aLen) { return mImpl.reserve(aLen); }
514
515 // -- Lookups --------------------------------------------------------------
516
517 // Does the set contain an element matching |aLookup|?
518 bool has(const Lookup& aLookup) const {
519 return mImpl.lookup(aLookup).found();
520 }
521
522 // Return a Ptr indicating whether an element matching |aLookup| is present
523 // in the set. E.g.:
524 //
525 // using HS = HashSet<int>;
526 // HS h;
527 // if (HS::Ptr p = h.lookup(3)) {
528 // assert(*p == 3); // p acts like a pointer to int
529 // }
530 //
531 using Ptr = typename Impl::Ptr;
532 MOZ_ALWAYS_INLINEinline Ptr lookup(const Lookup& aLookup) const {
533 return mImpl.lookup(aLookup);
534 }
535
536 // Like lookup(), but does not assert if two threads call it at the same
537 // time. Only use this method when none of the threads will modify the set.
538 MOZ_ALWAYS_INLINEinline Ptr readonlyThreadsafeLookup(const Lookup& aLookup) const {
539 return mImpl.readonlyThreadsafeLookup(aLookup);
540 }
541
542 // -- Insertions -----------------------------------------------------------
543
544 // Add |aU| if it is not present already. Returns false on OOM.
545 template <typename U>
546 [[nodiscard]] bool put(U&& aU) {
547 AddPtr p = lookupForAdd(aU);
548 return p ? true : add(p, std::forward<U>(aU));
549 }
550
551 // Like put(), but slightly faster. Must only be used when the given element
552 // is not already present. (In debug builds, assertions check this.)
553 template <typename U>
554 [[nodiscard]] bool putNew(U&& aU) {
555 return mImpl.putNew(aU, std::forward<U>(aU));
556 }
557
558 // Like the other putNew(), but for when |Lookup| is different to |T|.
559 template <typename U>
560 [[nodiscard]] bool putNew(const Lookup& aLookup, U&& aU) {
561 return mImpl.putNew(aLookup, std::forward<U>(aU));
562 }
563
564 // Like putNew(), but should be only used when the table is known to be big
565 // enough for the insertion, and hashing cannot fail. Typically this is used
566 // to populate an empty set with known-unique elements after reserving space
567 // with reserve(), e.g.
568 //
569 // using HS = HashMap<int>;
570 // HS h;
571 // if (!h.reserve(3)) {
572 // MOZ_CRASH("OOM");
573 // }
574 // h.putNewInfallible(1); // unique element
575 // h.putNewInfallible(2); // unique element
576 // h.putNewInfallible(3); // unique element
577 //
578 template <typename U>
579 void putNewInfallible(const Lookup& aLookup, U&& aU) {
580 mImpl.putNewInfallible(aLookup, std::forward<U>(aU));
581 }
582
583 // Like |lookup(l)|, but on miss, |p = lookupForAdd(l)| allows efficient
584 // insertion of T value |t| (where |HashPolicy::match(t,l) == true|) using
585 // |add(p,t)|. After |add(p,t)|, |p| points to the new element. E.g.:
586 //
587 // using HS = HashSet<int>;
588 // HS h;
589 // HS::AddPtr p = h.lookupForAdd(3);
590 // if (!p) {
591 // if (!h.add(p, 3)) {
592 // return false;
593 // }
594 // }
595 // assert(*p == 3); // p acts like a pointer to int
596 //
597 // N.B. The caller must ensure that no mutating hash table operations occur
598 // between a pair of lookupForAdd() and add() calls. To avoid looking up the
599 // key a second time, the caller may use the more efficient relookupOrAdd()
600 // method. This method reuses part of the hashing computation to more
601 // efficiently insert the key if it has not been added. For example, a
602 // mutation-handling version of the previous example:
603 //
604 // HS::AddPtr p = h.lookupForAdd(3);
605 // if (!p) {
606 // call_that_may_mutate_h();
607 // if (!h.relookupOrAdd(p, 3, 3)) {
608 // return false;
609 // }
610 // }
611 // assert(*p == 3);
612 //
613 // Note that relookupOrAdd(p,l,t) performs Lookup using |l| and adds the
614 // entry |t|, where the caller ensures match(l,t).
615 using AddPtr = typename Impl::AddPtr;
616 MOZ_ALWAYS_INLINEinline AddPtr lookupForAdd(const Lookup& aLookup) {
617 return mImpl.lookupForAdd(aLookup);
618 }
619
620 // Add an element. Returns false on OOM.
621 template <typename U>
622 [[nodiscard]] bool add(AddPtr& aPtr, U&& aU) {
623 return mImpl.add(aPtr, std::forward<U>(aU));
624 }
625
626 // See the comment above lookupForAdd() for details.
627 template <typename U>
628 [[nodiscard]] bool relookupOrAdd(AddPtr& aPtr, const Lookup& aLookup,
629 U&& aU) {
630 return mImpl.relookupOrAdd(aPtr, aLookup, std::forward<U>(aU));
631 }
632
633 // -- Removal --------------------------------------------------------------
634
635 // Lookup and remove the element matching |aLookup|, if present.
636 void remove(const Lookup& aLookup) {
637 if (Ptr p = lookup(aLookup)) {
638 remove(p);
639 }
640 }
641
642 // Remove a previously found element (assuming aPtr.found()). The set must
643 // not have been mutated in the interim.
644 void remove(Ptr aPtr) { mImpl.remove(aPtr); }
645
646 // Remove all keys/values without changing the capacity.
647 void clear() { mImpl.clear(); }
648
649 // Like clear() followed by compact().
650 void clearAndCompact() { mImpl.clearAndCompact(); }
651
652 // -- Rekeying -------------------------------------------------------------
653
654 // Infallibly rekey one entry, if present. Requires that template parameters
655 // T and HashPolicy::Lookup are the same type.
656 void rekeyIfMoved(const Lookup& aOldValue, const T& aNewValue) {
657 if (aOldValue != aNewValue) {
658 rekeyAs(aOldValue, aNewValue, aNewValue);
659 }
660 }
661
662 // Infallibly rekey one entry if present, and return whether that happened.
663 bool rekeyAs(const Lookup& aOldLookup, const Lookup& aNewLookup,
664 const T& aNewValue) {
665 if (Ptr p = lookup(aOldLookup)) {
666 mImpl.rekeyAndMaybeRehash(p, aNewLookup, aNewValue);
667 return true;
668 }
669 return false;
670 }
671
672 // Infallibly replace the current key at |aPtr| with an equivalent key.
673 // Specifically, both HashPolicy::hash and HashPolicy::match must return
674 // identical results for the new and old key when applied against all
675 // possible matching values.
676 void replaceKey(Ptr aPtr, const Lookup& aLookup, const T& aNewValue) {
677 MOZ_ASSERT(aPtr.found())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(aPtr.found())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(aPtr.found()))), 0))) { do {
} while (false); MOZ_ReportAssertionFailure("aPtr.found()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 677); AnnotateMozCrashReason("MOZ_ASSERT" "(" "aPtr.found()"
")"); do { *((volatile int*)__null) = 677; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
678 MOZ_ASSERT(*aPtr != aNewValue)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(*aPtr != aNewValue)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(*aPtr != aNewValue))), 0))) {
do { } while (false); MOZ_ReportAssertionFailure("*aPtr != aNewValue"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 678); AnnotateMozCrashReason("MOZ_ASSERT" "(" "*aPtr != aNewValue"
")"); do { *((volatile int*)__null) = 678; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
679 MOZ_ASSERT(HashPolicy::match(*aPtr, aLookup))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(HashPolicy::match(*aPtr, aLookup))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(HashPolicy::match(*aPtr, aLookup
)))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("HashPolicy::match(*aPtr, aLookup)", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 679); AnnotateMozCrashReason("MOZ_ASSERT" "(" "HashPolicy::match(*aPtr, aLookup)"
")"); do { *((volatile int*)__null) = 679; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
680 MOZ_ASSERT(HashPolicy::match(aNewValue, aLookup))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(HashPolicy::match(aNewValue, aLookup))>::isValid,
"invalid assertion condition"); if ((__builtin_expect(!!(!(!
!(HashPolicy::match(aNewValue, aLookup)))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("HashPolicy::match(aNewValue, aLookup)"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 680); AnnotateMozCrashReason("MOZ_ASSERT" "(" "HashPolicy::match(aNewValue, aLookup)"
")"); do { *((volatile int*)__null) = 680; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
681 const_cast<T&>(*aPtr) = aNewValue;
682 MOZ_ASSERT(*lookup(aLookup) == aNewValue)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(*lookup(aLookup) == aNewValue)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(*lookup(aLookup) == aNewValue
))), 0))) { do { } while (false); MOZ_ReportAssertionFailure(
"*lookup(aLookup) == aNewValue", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 682); AnnotateMozCrashReason("MOZ_ASSERT" "(" "*lookup(aLookup) == aNewValue"
")"); do { *((volatile int*)__null) = 682; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
683 }
684 void replaceKey(Ptr aPtr, const T& aNewValue) {
685 replaceKey(aPtr, aNewValue, aNewValue);
686 }
687
688 // -- Iteration ------------------------------------------------------------
689
690 // |iter()| returns an Iterator:
691 //
692 // HashSet<int> h;
693 // for (auto iter = h.iter(); !iter.done(); iter.next()) {
694 // int i = iter.get();
695 // }
696 //
697 using Iterator = typename Impl::Iterator;
698 Iterator iter() const { return mImpl.iter(); }
699
700 // |modIter()| returns a ModIterator:
701 //
702 // HashSet<int> h;
703 // for (auto iter = h.modIter(); !iter.done(); iter.next()) {
704 // if (iter.get() == 42) {
705 // iter.remove();
706 // }
707 // }
708 //
709 // Table resize may occur in ModIterator's destructor.
710 using ModIterator = typename Impl::ModIterator;
711 ModIterator modIter() { return mImpl.modIter(); }
712
713 // These are similar to Iterator/ModIterator/iter(), but use different
714 // terminology.
715 using Range = typename Impl::Range;
716 using Enum = typename Impl::Enum;
717 Range all() const { return mImpl.all(); }
718};
719
720//---------------------------------------------------------------------------
721// Hash Policy
722//---------------------------------------------------------------------------
723
724// A hash policy |HP| for a hash table with key-type |Key| must provide:
725//
726// - a type |HP::Lookup| to use to lookup table entries;
727//
728// - a static member function |HP::hash| that hashes lookup values:
729//
730// static mozilla::HashNumber hash(const Lookup&);
731//
732// - a static member function |HP::match| that tests equality of key and
733// lookup values:
734//
735// static bool match(const Key& aKey, const Lookup& aLookup);
736//
737// |aKey| and |aLookup| can have different hash numbers, only when a
738// collision happens with |prepareHash| operation, which is less frequent.
739// Thus, |HP::match| shouldn't assume the hash equality in the comparison,
740// even if the hash numbers are almost always same between them.
741//
742// Normally, Lookup = Key. In general, though, different values and types of
743// values can be used to lookup and store. If a Lookup value |l| is not equal
744// to the added Key value |k|, the user must ensure that |HP::match(k,l)| is
745// true. E.g.:
746//
747// mozilla::HashSet<Key, HP>::AddPtr p = h.lookup(l);
748// if (!p) {
749// assert(HP::match(k, l)); // must hold
750// h.add(p, k);
751// }
752
753// A pointer hashing policy that uses HashGeneric() to create good hashes for
754// pointers. Note that we don't shift out the lowest k bits because we don't
755// want to assume anything about the alignment of the pointers.
756template <typename Key>
757struct PointerHasher {
758 using Lookup = Key;
759
760 static HashNumber hash(const Lookup& aLookup) { return HashGeneric(aLookup); }
761
762 static bool match(const Key& aKey, const Lookup& aLookup) {
763 return aKey == aLookup;
764 }
765
766 static void rekey(Key& aKey, const Key& aNewKey) { aKey = aNewKey; }
767};
768
769// The default hash policy, which only works with integers.
770template <class Key, typename>
771struct DefaultHasher {
772 using Lookup = Key;
773
774 static HashNumber hash(const Lookup& aLookup) {
775 // Just convert the integer to a HashNumber and use that as is. (This
776 // discards the high 32-bits of 64-bit integers!) ScrambleHashCode() is
777 // subsequently called on the value to improve the distribution.
778 return aLookup;
779 }
780
781 static bool match(const Key& aKey, const Lookup& aLookup) {
782 // Use builtin or overloaded operator==.
783 return aKey == aLookup;
784 }
785
786 static void rekey(Key& aKey, const Key& aNewKey) { aKey = aNewKey; }
787};
788
789// A DefaultHasher specialization for enums.
790template <class T>
791struct DefaultHasher<T, std::enable_if_t<std::is_enum_v<T>>> {
792 using Key = T;
793 using Lookup = Key;
794
795 static HashNumber hash(const Lookup& aLookup) { return HashGeneric(aLookup); }
796
797 static bool match(const Key& aKey, const Lookup& aLookup) {
798 // Use builtin or overloaded operator==.
799 return aKey == static_cast<Key>(aLookup);
800 }
801
802 static void rekey(Key& aKey, const Key& aNewKey) { aKey = aNewKey; }
803};
804
805// A DefaultHasher specialization for pointers.
806template <class T>
807struct DefaultHasher<T*> : PointerHasher<T*> {};
808
809// A DefaultHasher specialization for mozilla::UniquePtr.
810template <class T, class D>
811struct DefaultHasher<UniquePtr<T, D>> {
812 using Key = UniquePtr<T, D>;
813 using Lookup = Key;
814 using PtrHasher = PointerHasher<T*>;
815
816 static HashNumber hash(const Lookup& aLookup) {
817 return PtrHasher::hash(aLookup.get());
818 }
819
820 static bool match(const Key& aKey, const Lookup& aLookup) {
821 return PtrHasher::match(aKey.get(), aLookup.get());
822 }
823
824 static void rekey(UniquePtr<T, D>& aKey, UniquePtr<T, D>&& aNewKey) {
825 aKey = std::move(aNewKey);
826 }
827};
828
829// A DefaultHasher specialization for doubles.
830template <>
831struct DefaultHasher<double> {
832 using Key = double;
833 using Lookup = Key;
834
835 static HashNumber hash(const Lookup& aLookup) {
836 // Just xor the high bits with the low bits, and then treat the bits of the
837 // result as a uint32_t.
838 static_assert(sizeof(HashNumber) == 4,
839 "subsequent code assumes a four-byte hash");
840 uint64_t u = BitwiseCast<uint64_t>(aLookup);
841 return HashNumber(u ^ (u >> 32));
842 }
843
844 static bool match(const Key& aKey, const Lookup& aLookup) {
845 return BitwiseCast<uint64_t>(aKey) == BitwiseCast<uint64_t>(aLookup);
846 }
847};
848
849// A DefaultHasher specialization for floats.
850template <>
851struct DefaultHasher<float> {
852 using Key = float;
853 using Lookup = Key;
854
855 static HashNumber hash(const Lookup& aLookup) {
856 // Just use the value as if its bits form an integer. ScrambleHashCode() is
857 // subsequently called on the value to improve the distribution.
858 static_assert(sizeof(HashNumber) == 4,
859 "subsequent code assumes a four-byte hash");
860 return HashNumber(BitwiseCast<uint32_t>(aLookup));
861 }
862
863 static bool match(const Key& aKey, const Lookup& aLookup) {
864 return BitwiseCast<uint32_t>(aKey) == BitwiseCast<uint32_t>(aLookup);
865 }
866};
867
868// A hash policy for C strings.
869struct CStringHasher {
870 using Key = const char*;
871 using Lookup = const char*;
872
873 static HashNumber hash(const Lookup& aLookup) { return HashString(aLookup); }
874
875 static bool match(const Key& aKey, const Lookup& aLookup) {
876 return strcmp(aKey, aLookup) == 0;
877 }
878};
879
880//---------------------------------------------------------------------------
881// Fallible Hashing Interface
882//---------------------------------------------------------------------------
883
884// Most of the time generating a hash code is infallible, but sometimes it is
885// necessary to generate hash codes on demand in a way that can fail. Specialize
886// this class for your own hash policy to provide fallible hashing.
887//
888// This is used by MovableCellHasher to handle the fact that generating a unique
889// ID for cell pointer may fail due to OOM.
890//
891// The default implementations of these methods delegate to the usual HashPolicy
892// implementation and always succeed.
893template <typename HashPolicy>
894struct FallibleHashMethods {
895 // Return true if a hashcode is already available for its argument, and
896 // sets |aHashOut|. Once this succeeds for a specific argument it
897 // must continue to do so.
898 //
899 // Return false if a hashcode is not already available. This implies that any
900 // lookup must fail, as the hash code would have to have been successfully
901 // created on insertion.
902 template <typename Lookup>
903 static bool maybeGetHash(Lookup&& aLookup, HashNumber* aHashOut) {
904 *aHashOut = HashPolicy::hash(aLookup);
905 return true;
906 }
907
908 // Fallible method to ensure a hashcode exists for its argument and create one
909 // if not. Sets |aHashOut| to the hashcode and retuns true on success. Returns
910 // false on error, e.g. out of memory.
911 template <typename Lookup>
912 static bool ensureHash(Lookup&& aLookup, HashNumber* aHashOut) {
913 *aHashOut = HashPolicy::hash(aLookup);
914 return true;
915 }
916};
917
918template <typename HashPolicy, typename Lookup>
919static bool MaybeGetHash(Lookup&& aLookup, HashNumber* aHashOut) {
920 return FallibleHashMethods<typename HashPolicy::Base>::maybeGetHash(
921 std::forward<Lookup>(aLookup), aHashOut);
922}
923
924template <typename HashPolicy, typename Lookup>
925static bool EnsureHash(Lookup&& aLookup, HashNumber* aHashOut) {
926 return FallibleHashMethods<typename HashPolicy::Base>::ensureHash(
927 std::forward<Lookup>(aLookup), aHashOut);
928}
929
930//---------------------------------------------------------------------------
931// Implementation Details (HashMapEntry, HashTableEntry, HashTable)
932//---------------------------------------------------------------------------
933
934// Both HashMap and HashSet are implemented by a single HashTable that is even
935// more heavily parameterized than the other two. This leaves HashTable gnarly
936// and extremely coupled to HashMap and HashSet; thus code should not use
937// HashTable directly.
938
939template <class Key, class Value>
940class HashMapEntry {
941 Key key_;
942 Value value_;
943
944 template <class, class, class>
945 friend class detail::HashTable;
946 template <class>
947 friend class detail::HashTableEntry;
948 template <class, class, class, class>
949 friend class HashMap;
950
951 public:
952 template <typename KeyInput, typename ValueInput>
953 HashMapEntry(KeyInput&& aKey, ValueInput&& aValue)
954 : key_(std::forward<KeyInput>(aKey)),
955 value_(std::forward<ValueInput>(aValue)) {}
956
957 HashMapEntry(HashMapEntry&& aRhs) = default;
958 HashMapEntry& operator=(HashMapEntry&& aRhs) = default;
959
960 using KeyType = Key;
961 using ValueType = Value;
962
963 const Key& key() const { return key_; }
964
965 // Use this method with caution! If the key is changed such that its hash
966 // value also changes, the map will be left in an invalid state.
967 Key& mutableKey() { return key_; }
968
969 const Value& value() const { return value_; }
970 Value& value() { return value_; }
971
972 private:
973 HashMapEntry(const HashMapEntry&) = delete;
974 void operator=(const HashMapEntry&) = delete;
975};
976
977namespace detail {
978
979template <class T, class HashPolicy, class AllocPolicy>
980class HashTable;
981
982template <typename T>
983class EntrySlot;
984
985template <typename T>
986class HashTableEntry {
987 private:
988 using NonConstT = std::remove_const_t<T>;
989
990 // Instead of having a hash table entry store that looks like this:
991 //
992 // +--------+--------+--------+--------+
993 // | entry0 | entry1 | .... | entryN |
994 // +--------+--------+--------+--------+
995 //
996 // where the entries contained their cached hash code, we're going to lay out
997 // the entry store thusly:
998 //
999 // +-------+-------+-------+-------+--------+--------+--------+--------+
1000 // | hash0 | hash1 | ... | hashN | entry0 | entry1 | .... | entryN |
1001 // +-------+-------+-------+-------+--------+--------+--------+--------+
1002 //
1003 // with all the cached hashes prior to the actual entries themselves.
1004 //
1005 // We do this because implementing the first strategy requires us to make
1006 // HashTableEntry look roughly like:
1007 //
1008 // template <typename T>
1009 // class HashTableEntry {
1010 // HashNumber mKeyHash;
1011 // T mValue;
1012 // };
1013 //
1014 // The problem with this setup is that, depending on the layout of `T`, there
1015 // may be platform ABI-mandated padding between `mKeyHash` and the first
1016 // member of `T`. This ABI-mandated padding is wasted space, and can be
1017 // surprisingly common, e.g. when `T` is a single pointer on 64-bit platforms.
1018 // In such cases, we're throwing away a quarter of our entry store on padding,
1019 // which is undesirable.
1020 //
1021 // The second layout above, namely:
1022 //
1023 // +-------+-------+-------+-------+--------+--------+--------+--------+
1024 // | hash0 | hash1 | ... | hashN | entry0 | entry1 | .... | entryN |
1025 // +-------+-------+-------+-------+--------+--------+--------+--------+
1026 //
1027 // means there is no wasted space between the hashes themselves, and no wasted
1028 // space between the entries themselves. However, we would also like there to
1029 // be no gap between the last hash and the first entry. The memory allocator
1030 // guarantees the alignment of the start of the hashes. The use of a
1031 // power-of-two capacity of at least 4 guarantees that the alignment of the
1032 // *end* of the hash array is no less than the alignment of the start.
1033 // Finally, the static_asserts here guarantee that the entries themselves
1034 // don't need to be any more aligned than the alignment of the entry store
1035 // itself.
1036 //
1037 // This assertion is safe for 32-bit builds because on both Windows and Linux
1038 // (including Android), the minimum alignment for allocations larger than 8
1039 // bytes is 8 bytes, and the actual data for entries in our entry store is
1040 // guaranteed to have that alignment as well, thanks to the power-of-two
1041 // number of cached hash values stored prior to the entry data.
1042
1043 // The allocation policy must allocate a table with at least this much
1044 // alignment.
1045 static constexpr size_t kMinimumAlignment = 8;
1046
1047 static_assert(alignof(HashNumber) <= kMinimumAlignment,
1048 "[N*2 hashes, N*2 T values] allocation's alignment must be "
1049 "enough to align each hash");
1050 static_assert(alignof(NonConstT) <= 2 * sizeof(HashNumber),
1051 "subsequent N*2 T values must not require more than an even "
1052 "number of HashNumbers provides");
1053
1054 static const HashNumber sFreeKey = 0;
1055 static const HashNumber sRemovedKey = 1;
1056 static const HashNumber sCollisionBit = 1;
1057
1058 alignas(NonConstT) unsigned char mValueData[sizeof(NonConstT)];
1059
1060 private:
1061 template <class, class, class>
1062 friend class HashTable;
1063 template <typename>
1064 friend class EntrySlot;
1065
1066 // Some versions of GCC treat it as a -Wstrict-aliasing violation (ergo a
1067 // -Werror compile error) to reinterpret_cast<> |mValueData| to |T*|, even
1068 // through |void*|. Placing the latter cast in these separate functions
1069 // breaks the chain such that affected GCC versions no longer warn/error.
1070 void* rawValuePtr() { return mValueData; }
1071
1072 static bool isLiveHash(HashNumber hash) { return hash > sRemovedKey; }
1073
1074 HashTableEntry(const HashTableEntry&) = delete;
1075 void operator=(const HashTableEntry&) = delete;
1076
1077 NonConstT* valuePtr() { return reinterpret_cast<NonConstT*>(rawValuePtr()); }
1078
1079 void destroyStoredT() {
1080 NonConstT* ptr = valuePtr();
1081 ptr->~T();
1082 MOZ_MAKE_MEM_UNDEFINED(ptr, sizeof(*ptr))do { } while (0);
1083 }
1084
1085 public:
1086 HashTableEntry() = default;
1087
1088 ~HashTableEntry() { MOZ_MAKE_MEM_UNDEFINED(this, sizeof(*this))do { } while (0); }
1089
1090 void destroy() { destroyStoredT(); }
1091
1092 void swap(HashTableEntry* aOther, bool aIsLive) {
1093 // This allows types to use Argument-Dependent-Lookup, and thus use a custom
1094 // std::swap, which is needed by types like JS::Heap and such.
1095 using std::swap;
1096
1097 if (this == aOther) {
1098 return;
1099 }
1100 if (aIsLive) {
1101 swap(*valuePtr(), *aOther->valuePtr());
1102 } else {
1103 *aOther->valuePtr() = std::move(*valuePtr());
1104 destroy();
1105 }
1106 }
1107
1108 T& get() { return *valuePtr(); }
1109
1110 NonConstT& getMutable() { return *valuePtr(); }
1111};
1112
1113// A slot represents a cached hash value and its associated entry stored
1114// in the hash table. These two things are not stored in contiguous memory.
1115template <class T>
1116class EntrySlot {
1117 using NonConstT = std::remove_const_t<T>;
1118
1119 using Entry = HashTableEntry<T>;
1120
1121 Entry* mEntry;
1122 HashNumber* mKeyHash;
1123
1124 template <class, class, class>
1125 friend class HashTable;
1126
1127 EntrySlot(Entry* aEntry, HashNumber* aKeyHash)
1128 : mEntry(aEntry), mKeyHash(aKeyHash) {}
1129
1130 public:
1131 static bool isLiveHash(HashNumber hash) { return hash > Entry::sRemovedKey; }
1132
1133 EntrySlot(const EntrySlot&) = default;
1134 EntrySlot(EntrySlot&& aOther) = default;
1135
1136 EntrySlot& operator=(const EntrySlot&) = default;
1137 EntrySlot& operator=(EntrySlot&&) = default;
1138
1139 bool operator==(const EntrySlot& aRhs) const { return mEntry == aRhs.mEntry; }
1140
1141 bool operator<(const EntrySlot& aRhs) const { return mEntry < aRhs.mEntry; }
1142
1143 EntrySlot& operator++() {
1144 ++mEntry;
1145 ++mKeyHash;
1146 return *this;
1147 }
1148
1149 void destroy() { mEntry->destroy(); }
1150
1151 void swap(EntrySlot& aOther) {
1152 mEntry->swap(aOther.mEntry, aOther.isLive());
1153 std::swap(*mKeyHash, *aOther.mKeyHash);
1154 }
1155
1156 T& get() const { return mEntry->get(); }
1157
1158 NonConstT& getMutable() { return mEntry->getMutable(); }
1159
1160 bool isFree() const { return *mKeyHash == Entry::sFreeKey; }
1161
1162 void clearLive() {
1163 MOZ_ASSERT(isLive())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isLive())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isLive()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isLive()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1163); AnnotateMozCrashReason("MOZ_ASSERT" "(" "isLive()" ")"
); do { *((volatile int*)__null) = 1163; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1164 *mKeyHash = Entry::sFreeKey;
1165 mEntry->destroyStoredT();
1166 }
1167
1168 void clear() {
1169 if (isLive()) {
1170 mEntry->destroyStoredT();
1171 }
1172 MOZ_MAKE_MEM_UNDEFINED(mEntry, sizeof(*mEntry))do { } while (0);
1173 *mKeyHash = Entry::sFreeKey;
1174 }
1175
1176 bool isRemoved() const { return *mKeyHash == Entry::sRemovedKey; }
1177
1178 void removeLive() {
1179 MOZ_ASSERT(isLive())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isLive())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isLive()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isLive()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1179); AnnotateMozCrashReason("MOZ_ASSERT" "(" "isLive()" ")"
); do { *((volatile int*)__null) = 1179; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1180 *mKeyHash = Entry::sRemovedKey;
1181 mEntry->destroyStoredT();
1182 }
1183
1184 bool isLive() const { return isLiveHash(*mKeyHash); }
1185
1186 void setCollision() {
1187 MOZ_ASSERT(isLive())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isLive())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isLive()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isLive()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1187); AnnotateMozCrashReason("MOZ_ASSERT" "(" "isLive()" ")"
); do { *((volatile int*)__null) = 1187; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1188 *mKeyHash |= Entry::sCollisionBit;
1189 }
1190 void unsetCollision() { *mKeyHash &= ~Entry::sCollisionBit; }
1191 bool hasCollision() const { return *mKeyHash & Entry::sCollisionBit; }
1192 bool matchHash(HashNumber hn) {
1193 return (*mKeyHash & ~Entry::sCollisionBit) == hn;
1194 }
1195 HashNumber getKeyHash() const { return *mKeyHash & ~Entry::sCollisionBit; }
1196
1197 template <typename... Args>
1198 void setLive(HashNumber aHashNumber, Args&&... aArgs) {
1199 MOZ_ASSERT(!isLive())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!isLive())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!isLive()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("!isLive()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1199); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!isLive()" ")"
); do { *((volatile int*)__null) = 1199; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1200 *mKeyHash = aHashNumber;
1201 new (KnownNotNull, mEntry->valuePtr()) T(std::forward<Args>(aArgs)...);
1202 MOZ_ASSERT(isLive())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isLive())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isLive()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isLive()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1202); AnnotateMozCrashReason("MOZ_ASSERT" "(" "isLive()" ")"
); do { *((volatile int*)__null) = 1202; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1203 }
1204
1205 Entry* toEntry() const { return mEntry; }
1206};
1207
1208template <class T, class HashPolicy, class AllocPolicy>
1209class HashTable : private AllocPolicy {
1210 friend class mozilla::ReentrancyGuard;
1211
1212 using NonConstT = std::remove_const_t<T>;
1213 using Key = typename HashPolicy::KeyType;
1214 using Lookup = typename HashPolicy::Lookup;
1215
1216 public:
1217 using Entry = HashTableEntry<T>;
1218 using Slot = EntrySlot<T>;
1219
1220 template <typename F>
1221 static void forEachSlot(char* aTable, uint32_t aCapacity, F&& f) {
1222 auto hashes = reinterpret_cast<HashNumber*>(aTable);
1223 auto entries = reinterpret_cast<Entry*>(&hashes[aCapacity]);
1224 Slot slot(entries, hashes);
1225 for (size_t i = 0; i < size_t(aCapacity); ++i) {
1226 f(slot);
1227 ++slot;
1228 }
1229 }
1230
1231 // A nullable pointer to a hash table element. A Ptr |p| can be tested
1232 // either explicitly |if (p.found()) p->...| or using boolean conversion
1233 // |if (p) p->...|. Ptr objects must not be used after any mutating hash
1234 // table operations unless |generation()| is tested.
1235 class Ptr {
1236 friend class HashTable;
1237
1238 Slot mSlot;
1239#ifdef DEBUG1
1240 const HashTable* mTable;
1241 Generation mGeneration;
1242#endif
1243
1244 protected:
1245 Ptr(Slot aSlot, const HashTable& aTable)
1246 : mSlot(aSlot)
1247#ifdef DEBUG1
1248 ,
1249 mTable(&aTable),
1250 mGeneration(aTable.generation())
1251#endif
1252 {
1253 }
1254
1255 // This constructor is used only by AddPtr() within lookupForAdd().
1256 explicit Ptr(const HashTable& aTable)
1257 : mSlot(nullptr, nullptr)
1258#ifdef DEBUG1
1259 ,
1260 mTable(&aTable),
1261 mGeneration(aTable.generation())
1262#endif
1263 {
1264 }
1265
1266 bool isValid() const { return !!mSlot.toEntry(); }
1267
1268 public:
1269 Ptr()
1270 : mSlot(nullptr, nullptr)
1271#ifdef DEBUG1
1272 ,
1273 mTable(nullptr),
1274 mGeneration(0)
1275#endif
1276 {
1277 }
1278
1279 bool found() const {
1280 if (!isValid()) {
1281 return false;
1282 }
1283#ifdef DEBUG1
1284 MOZ_ASSERT(mGeneration == mTable->generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mGeneration == mTable->generation())>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(mGeneration == mTable->generation()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mGeneration == mTable->generation()"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1284); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mGeneration == mTable->generation()"
")"); do { *((volatile int*)__null) = 1284; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1285#endif
1286 return mSlot.isLive();
1287 }
1288
1289 explicit operator bool() const { return found(); }
1290
1291 bool operator==(const Ptr& aRhs) const {
1292 MOZ_ASSERT(found() && aRhs.found())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(found() && aRhs.found())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(found() && aRhs.found
()))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("found() && aRhs.found()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1292); AnnotateMozCrashReason("MOZ_ASSERT" "(" "found() && aRhs.found()"
")"); do { *((volatile int*)__null) = 1292; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1293 return mSlot == aRhs.mSlot;
1294 }
1295
1296 bool operator!=(const Ptr& aRhs) const {
1297#ifdef DEBUG1
1298 MOZ_ASSERT(mGeneration == mTable->generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mGeneration == mTable->generation())>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(mGeneration == mTable->generation()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mGeneration == mTable->generation()"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1298); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mGeneration == mTable->generation()"
")"); do { *((volatile int*)__null) = 1298; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1299#endif
1300 return !(*this == aRhs);
1301 }
1302
1303 T& operator*() const {
1304#ifdef DEBUG1
1305 MOZ_ASSERT(found())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(found())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(found()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("found()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1305); AnnotateMozCrashReason("MOZ_ASSERT" "(" "found()" ")"
); do { *((volatile int*)__null) = 1305; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1306 MOZ_ASSERT(mGeneration == mTable->generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mGeneration == mTable->generation())>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(mGeneration == mTable->generation()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mGeneration == mTable->generation()"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1306); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mGeneration == mTable->generation()"
")"); do { *((volatile int*)__null) = 1306; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1307#endif
1308 return mSlot.get();
1309 }
1310
1311 T* operator->() const {
1312#ifdef DEBUG1
1313 MOZ_ASSERT(found())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(found())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(found()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("found()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1313); AnnotateMozCrashReason("MOZ_ASSERT" "(" "found()" ")"
); do { *((volatile int*)__null) = 1313; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1314 MOZ_ASSERT(mGeneration == mTable->generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mGeneration == mTable->generation())>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(mGeneration == mTable->generation()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mGeneration == mTable->generation()"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1314); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mGeneration == mTable->generation()"
")"); do { *((volatile int*)__null) = 1314; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1315#endif
1316 return &mSlot.get();
1317 }
1318 };
1319
1320 // A Ptr that can be used to add a key after a failed lookup.
1321 class AddPtr : public Ptr {
1322 friend class HashTable;
1323
1324 HashNumber mKeyHash;
1325#ifdef DEBUG1
1326 uint64_t mMutationCount;
1327#endif
1328
1329 AddPtr(Slot aSlot, const HashTable& aTable, HashNumber aHashNumber)
1330 : Ptr(aSlot, aTable),
1331 mKeyHash(aHashNumber)
1332#ifdef DEBUG1
1333 ,
1334 mMutationCount(aTable.mMutationCount)
1335#endif
1336 {
1337 }
1338
1339 // This constructor is used when lookupForAdd() is performed on a table
1340 // lacking entry storage; it leaves mSlot null but initializes everything
1341 // else.
1342 AddPtr(const HashTable& aTable, HashNumber aHashNumber)
1343 : Ptr(aTable),
1344 mKeyHash(aHashNumber)
1345#ifdef DEBUG1
1346 ,
1347 mMutationCount(aTable.mMutationCount)
1348#endif
1349 {
1350 MOZ_ASSERT(isLive())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isLive())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isLive()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("isLive()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1350); AnnotateMozCrashReason("MOZ_ASSERT" "(" "isLive()" ")"
); do { *((volatile int*)__null) = 1350; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1351 }
1352
1353 bool isLive() const { return isLiveHash(mKeyHash); }
1354
1355 public:
1356 AddPtr() : mKeyHash(0) {}
1357 };
1358
1359 // A hash table iterator that (mostly) doesn't allow table modifications.
1360 // As with Ptr/AddPtr, Iterator objects must not be used after any mutating
1361 // hash table operation unless the |generation()| is tested.
1362 class Iterator {
1363 void moveToNextLiveEntry() {
1364 while (++mCur < mEnd && !mCur.isLive()) {
1365 continue;
1366 }
1367 }
1368
1369 protected:
1370 friend class HashTable;
1371
1372 explicit Iterator(const HashTable& aTable)
1373 : mCur(aTable.slotForIndex(0)),
1374 mEnd(aTable.slotForIndex(aTable.capacity()))
1375#ifdef DEBUG1
1376 ,
1377 mTable(aTable),
1378 mMutationCount(aTable.mMutationCount),
1379 mGeneration(aTable.generation()),
1380 mValidEntry(true)
1381#endif
1382 {
1383 if (!done() && !mCur.isLive()) {
1384 moveToNextLiveEntry();
1385 }
1386 }
1387
1388 Slot mCur;
1389 Slot mEnd;
1390#ifdef DEBUG1
1391 const HashTable& mTable;
1392 uint64_t mMutationCount;
1393 Generation mGeneration;
1394 bool mValidEntry;
1395#endif
1396
1397 public:
1398 bool done() const {
1399 MOZ_ASSERT(mGeneration == mTable.generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mGeneration == mTable.generation())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(mGeneration == mTable.generation
()))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("mGeneration == mTable.generation()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1399); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mGeneration == mTable.generation()"
")"); do { *((volatile int*)__null) = 1399; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1400 MOZ_ASSERT(mMutationCount == mTable.mMutationCount)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mMutationCount == mTable.mMutationCount)>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(mMutationCount == mTable.mMutationCount))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mMutationCount == mTable.mMutationCount"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1400); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mMutationCount == mTable.mMutationCount"
")"); do { *((volatile int*)__null) = 1400; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1401 return mCur == mEnd;
1402 }
1403
1404 T& get() const {
1405 MOZ_ASSERT(!done())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!done())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!done()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("!done()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1405); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!done()" ")"
); do { *((volatile int*)__null) = 1405; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1406 MOZ_ASSERT(mValidEntry)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mValidEntry)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(mValidEntry))), 0))) { do { }
while (false); MOZ_ReportAssertionFailure("mValidEntry", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1406); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mValidEntry"
")"); do { *((volatile int*)__null) = 1406; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1407 MOZ_ASSERT(mGeneration == mTable.generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mGeneration == mTable.generation())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(mGeneration == mTable.generation
()))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("mGeneration == mTable.generation()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1407); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mGeneration == mTable.generation()"
")"); do { *((volatile int*)__null) = 1407; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1408 MOZ_ASSERT(mMutationCount == mTable.mMutationCount)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mMutationCount == mTable.mMutationCount)>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(mMutationCount == mTable.mMutationCount))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mMutationCount == mTable.mMutationCount"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1408); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mMutationCount == mTable.mMutationCount"
")"); do { *((volatile int*)__null) = 1408; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1409 return mCur.get();
1410 }
1411
1412 void next() {
1413 MOZ_ASSERT(!done())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!done())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!done()))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("!done()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1413); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!done()" ")"
); do { *((volatile int*)__null) = 1413; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1414 MOZ_ASSERT(mGeneration == mTable.generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mGeneration == mTable.generation())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(mGeneration == mTable.generation
()))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("mGeneration == mTable.generation()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1414); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mGeneration == mTable.generation()"
")"); do { *((volatile int*)__null) = 1414; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1415 MOZ_ASSERT(mMutationCount == mTable.mMutationCount)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mMutationCount == mTable.mMutationCount)>::isValid
, "invalid assertion condition"); if ((__builtin_expect(!!(!(
!!(mMutationCount == mTable.mMutationCount))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mMutationCount == mTable.mMutationCount"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1415); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mMutationCount == mTable.mMutationCount"
")"); do { *((volatile int*)__null) = 1415; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1416 moveToNextLiveEntry();
1417#ifdef DEBUG1
1418 mValidEntry = true;
1419#endif
1420 }
1421 };
1422
1423 // A hash table iterator that permits modification, removal and rekeying.
1424 // Since rehashing when elements were removed during enumeration would be
1425 // bad, it is postponed until the ModIterator is destructed. Since the
1426 // ModIterator's destructor touches the hash table, the user must ensure
1427 // that the hash table is still alive when the destructor runs.
1428 class ModIterator : public Iterator {
1429 friend class HashTable;
1430
1431 HashTable& mTable;
1432 bool mRekeyed;
1433 bool mRemoved;
1434
1435 // ModIterator is movable but not copyable.
1436 ModIterator(const ModIterator&) = delete;
1437 void operator=(const ModIterator&) = delete;
1438
1439 protected:
1440 explicit ModIterator(HashTable& aTable)
1441 : Iterator(aTable), mTable(aTable), mRekeyed(false), mRemoved(false) {}
1442
1443 public:
1444 MOZ_IMPLICIT ModIterator(ModIterator&& aOther)
1445 : Iterator(aOther),
1446 mTable(aOther.mTable),
1447 mRekeyed(aOther.mRekeyed),
1448 mRemoved(aOther.mRemoved) {
1449 aOther.mRekeyed = false;
1450 aOther.mRemoved = false;
1451 }
1452
1453 // Removes the current element from the table, leaving |get()|
1454 // invalid until the next call to |next()|.
1455 void remove() {
1456 mTable.remove(this->mCur);
1457 mRemoved = true;
1458#ifdef DEBUG1
1459 this->mValidEntry = false;
1460 this->mMutationCount = mTable.mMutationCount;
1461#endif
1462 }
1463
1464 NonConstT& getMutable() {
1465 MOZ_ASSERT(!this->done())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!this->done())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!this->done()))), 0))) { do
{ } while (false); MOZ_ReportAssertionFailure("!this->done()"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1465); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!this->done()"
")"); do { *((volatile int*)__null) = 1465; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1466 MOZ_ASSERT(this->mValidEntry)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(this->mValidEntry)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(this->mValidEntry))), 0))
) { do { } while (false); MOZ_ReportAssertionFailure("this->mValidEntry"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1466); AnnotateMozCrashReason("MOZ_ASSERT" "(" "this->mValidEntry"
")"); do { *((volatile int*)__null) = 1466; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1467 MOZ_ASSERT(this->mGeneration == this->Iterator::mTable.generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(this->mGeneration == this->Iterator::mTable.generation
())>::isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!(this->mGeneration == this->Iterator::mTable.generation
()))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("this->mGeneration == this->Iterator::mTable.generation()"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1467); AnnotateMozCrashReason("MOZ_ASSERT" "(" "this->mGeneration == this->Iterator::mTable.generation()"
")"); do { *((volatile int*)__null) = 1467; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1468 MOZ_ASSERT(this->mMutationCount == this->Iterator::mTable.mMutationCount)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(this->mMutationCount == this->Iterator::mTable
.mMutationCount)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(this->mMutationCount == this
->Iterator::mTable.mMutationCount))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("this->mMutationCount == this->Iterator::mTable.mMutationCount"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1468); AnnotateMozCrashReason("MOZ_ASSERT" "(" "this->mMutationCount == this->Iterator::mTable.mMutationCount"
")"); do { *((volatile int*)__null) = 1468; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1469 return this->mCur.getMutable();
1470 }
1471
1472 // Removes the current element and re-inserts it into the table with
1473 // a new key at the new Lookup position. |get()| is invalid after
1474 // this operation until the next call to |next()|.
1475 void rekey(const Lookup& l, const Key& k) {
1476 MOZ_ASSERT(&k != &HashPolicy::getKey(this->mCur.get()))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(&k != &HashPolicy::getKey(this->mCur.get(
)))>::isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!(&k != &HashPolicy::getKey(this->mCur.get(
))))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("&k != &HashPolicy::getKey(this->mCur.get())", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1476); AnnotateMozCrashReason("MOZ_ASSERT" "(" "&k != &HashPolicy::getKey(this->mCur.get())"
")"); do { *((volatile int*)__null) = 1476; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1477 Ptr p(this->mCur, mTable);
1478 mTable.rekeyWithoutRehash(p, l, k);
1479 mRekeyed = true;
1480#ifdef DEBUG1
1481 this->mValidEntry = false;
1482 this->mMutationCount = mTable.mMutationCount;
1483#endif
1484 }
1485
1486 void rekey(const Key& k) { rekey(k, k); }
1487
1488 // Potentially rehashes the table.
1489 ~ModIterator() {
1490 if (mRekeyed) {
1491 mTable.mGen++;
1492 mTable.infallibleRehashIfOverloaded();
1493 }
1494
1495 if (mRemoved) {
1496 mTable.compact();
1497 }
1498 }
1499 };
1500
1501 // Range is similar to Iterator, but uses different terminology.
1502 class Range {
1503 friend class HashTable;
1504
1505 Iterator mIter;
1506
1507 protected:
1508 explicit Range(const HashTable& table) : mIter(table) {}
1509
1510 public:
1511 bool empty() const { return mIter.done(); }
1512
1513 T& front() const { return mIter.get(); }
1514
1515 void popFront() { return mIter.next(); }
1516 };
1517
1518 // Enum is similar to ModIterator, but uses different terminology.
1519 class Enum {
1520 ModIterator mIter;
1521
1522 // Enum is movable but not copyable.
1523 Enum(const Enum&) = delete;
1524 void operator=(const Enum&) = delete;
1525
1526 public:
1527 template <class Map>
1528 explicit Enum(Map& map) : mIter(map.mImpl) {}
1529
1530 MOZ_IMPLICIT Enum(Enum&& other) : mIter(std::move(other.mIter)) {}
1531
1532 bool empty() const { return mIter.done(); }
1533
1534 T& front() const { return mIter.get(); }
1535
1536 void popFront() { return mIter.next(); }
1537
1538 void removeFront() { mIter.remove(); }
1539
1540 NonConstT& mutableFront() { return mIter.getMutable(); }
1541
1542 void rekeyFront(const Lookup& aLookup, const Key& aKey) {
1543 mIter.rekey(aLookup, aKey);
1544 }
1545
1546 void rekeyFront(const Key& aKey) { mIter.rekey(aKey); }
1547 };
1548
1549 // HashTable is movable
1550 HashTable(HashTable&& aRhs) : AllocPolicy(std::move(aRhs)) { moveFrom(aRhs); }
1551 HashTable& operator=(HashTable&& aRhs) {
1552 MOZ_ASSERT(this != &aRhs, "self-move assignment is prohibited")do { static_assert( mozilla::detail::AssertionConditionType<
decltype(this != &aRhs)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(this != &aRhs))), 0))) {
do { } while (false); MOZ_ReportAssertionFailure("this != &aRhs"
" (" "self-move assignment is prohibited" ")", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1552); AnnotateMozCrashReason("MOZ_ASSERT" "(" "this != &aRhs"
") (" "self-move assignment is prohibited" ")"); do { *((volatile
int*)__null) = 1552; __attribute__((nomerge)) ::abort(); } while
(false); } } while (false)
;
1553 if (mTable) {
1554 destroyTable(*this, mTable, capacity());
1555 }
1556 AllocPolicy::operator=(std::move(aRhs));
1557 moveFrom(aRhs);
1558 return *this;
1559 }
1560
1561 private:
1562 void moveFrom(HashTable& aRhs) {
1563 mGen = aRhs.mGen;
1564 mHashShift = aRhs.mHashShift;
1565 mTable = aRhs.mTable;
1566 mEntryCount = aRhs.mEntryCount;
1567 mRemovedCount = aRhs.mRemovedCount;
1568#ifdef DEBUG1
1569 mMutationCount = aRhs.mMutationCount;
1570 mEntered = aRhs.mEntered;
1571#endif
1572 aRhs.mTable = nullptr;
1573 aRhs.clearAndCompact();
1574 }
1575
1576 // HashTable is not copyable or assignable
1577 HashTable(const HashTable&) = delete;
1578 void operator=(const HashTable&) = delete;
1579
1580 static const uint32_t CAP_BITS = 30;
1581
1582 public:
1583 uint64_t mGen : 56; // entry storage generation number
1584 uint64_t mHashShift : 8; // multiplicative hash shift
1585 char* mTable; // entry storage
1586 uint32_t mEntryCount; // number of entries in mTable
1587 uint32_t mRemovedCount; // removed entry sentinels in mTable
1588
1589#ifdef DEBUG1
1590 uint64_t mMutationCount;
1591 mutable bool mEntered;
1592#endif
1593
1594 // The default initial capacity is 32 (enough to hold 16 elements), but it
1595 // can be as low as 4.
1596 static const uint32_t sDefaultLen = 16;
1597 static const uint32_t sMinCapacity = 4;
1598 // See the comments in HashTableEntry about this value.
1599 static_assert(sMinCapacity >= 4, "too-small sMinCapacity breaks assumptions");
1600 static const uint32_t sMaxInit = 1u << (CAP_BITS - 1);
1601 static const uint32_t sMaxCapacity = 1u << CAP_BITS;
1602
1603 // Hash-table alpha is conceptually a fraction, but to avoid floating-point
1604 // math we implement it as a ratio of integers.
1605 static const uint8_t sAlphaDenominator = 4;
1606 static const uint8_t sMinAlphaNumerator = 1; // min alpha: 1/4
1607 static const uint8_t sMaxAlphaNumerator = 3; // max alpha: 3/4
1608
1609 static const HashNumber sFreeKey = Entry::sFreeKey;
1610 static const HashNumber sRemovedKey = Entry::sRemovedKey;
1611 static const HashNumber sCollisionBit = Entry::sCollisionBit;
1612
1613 static uint32_t bestCapacity(uint32_t aLen) {
1614 static_assert(
1615 (sMaxInit * sAlphaDenominator) / sAlphaDenominator == sMaxInit,
1616 "multiplication in numerator below could overflow");
1617 static_assert(
1618 sMaxInit * sAlphaDenominator <= UINT32_MAX(4294967295U) - sMaxAlphaNumerator,
1619 "numerator calculation below could potentially overflow");
1620
1621 // Callers should ensure this is true.
1622 MOZ_ASSERT(aLen <= sMaxInit)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(aLen <= sMaxInit)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(aLen <= sMaxInit))), 0)))
{ do { } while (false); MOZ_ReportAssertionFailure("aLen <= sMaxInit"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1622); AnnotateMozCrashReason("MOZ_ASSERT" "(" "aLen <= sMaxInit"
")"); do { *((volatile int*)__null) = 1622; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1623
1624 // Compute the smallest capacity allowing |aLen| elements to be
1625 // inserted without rehashing: ceil(aLen / max-alpha). (Ceiling
1626 // integral division: <http://stackoverflow.com/a/2745086>.)
1627 uint32_t capacity = (aLen * sAlphaDenominator + sMaxAlphaNumerator - 1) /
1628 sMaxAlphaNumerator;
1629 capacity = (capacity < sMinCapacity) ? sMinCapacity : RoundUpPow2(capacity);
1630
1631 MOZ_ASSERT(capacity >= aLen)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(capacity >= aLen)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(capacity >= aLen))), 0)))
{ do { } while (false); MOZ_ReportAssertionFailure("capacity >= aLen"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1631); AnnotateMozCrashReason("MOZ_ASSERT" "(" "capacity >= aLen"
")"); do { *((volatile int*)__null) = 1631; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1632 MOZ_ASSERT(capacity <= sMaxCapacity)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(capacity <= sMaxCapacity)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(capacity <= sMaxCapacity)
)), 0))) { do { } while (false); MOZ_ReportAssertionFailure("capacity <= sMaxCapacity"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1632); AnnotateMozCrashReason("MOZ_ASSERT" "(" "capacity <= sMaxCapacity"
")"); do { *((volatile int*)__null) = 1632; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1633
1634 return capacity;
1635 }
1636
1637 static uint32_t hashShift(uint32_t aLen) {
1638 // Reject all lengths whose initial computed capacity would exceed
1639 // sMaxCapacity. Round that maximum aLen down to the nearest power of two
1640 // for speedier code.
1641 if (MOZ_UNLIKELY(aLen > sMaxInit)(__builtin_expect(!!(aLen > sMaxInit), 0))) {
1642 MOZ_CRASH("initial length is too large")do { do { } while (false); MOZ_ReportCrash("" "initial length is too large"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1642); AnnotateMozCrashReason("MOZ_CRASH(" "initial length is too large"
")"); do { *((volatile int*)__null) = 1642; __attribute__((nomerge
)) ::abort(); } while (false); } while (false)
;
1643 }
1644
1645 return kHashNumberBits - mozilla::CeilingLog2(bestCapacity(aLen));
1646 }
1647
1648 static bool isLiveHash(HashNumber aHash) { return Entry::isLiveHash(aHash); }
1649
1650 static HashNumber prepareHash(HashNumber aInputHash) {
1651 HashNumber keyHash = ScrambleHashCode(aInputHash);
1652
1653 // Avoid reserved hash codes.
1654 if (!isLiveHash(keyHash)) {
1655 keyHash -= (sRemovedKey + 1);
1656 }
1657 return keyHash & ~sCollisionBit;
1658 }
1659
1660 enum FailureBehavior { DontReportFailure = false, ReportFailure = true };
1661
1662 // Fake a struct that we're going to alloc. See the comments in
1663 // HashTableEntry about how the table is laid out, and why it's safe.
1664 struct FakeSlot {
1665 unsigned char c[sizeof(HashNumber) + sizeof(typename Entry::NonConstT)];
1666 };
1667
1668 static char* createTable(AllocPolicy& aAllocPolicy, uint32_t aCapacity,
1669 FailureBehavior aReportFailure = ReportFailure) {
1670 FakeSlot* fake =
1671 aReportFailure
1672 ? aAllocPolicy.template pod_malloc<FakeSlot>(aCapacity)
1673 : aAllocPolicy.template maybe_pod_malloc<FakeSlot>(aCapacity);
1674
1675 MOZ_ASSERT((reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment) ==do { static_assert( mozilla::detail::AssertionConditionType<
decltype((reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment
) == 0)>::isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!((reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment
) == 0))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("(reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment) == 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1676); AnnotateMozCrashReason("MOZ_ASSERT" "(" "(reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment) == 0"
")"); do { *((volatile int*)__null) = 1676; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
1676 0)do { static_assert( mozilla::detail::AssertionConditionType<
decltype((reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment
) == 0)>::isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!((reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment
) == 0))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("(reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment) == 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1676); AnnotateMozCrashReason("MOZ_ASSERT" "(" "(reinterpret_cast<uintptr_t>(fake) % Entry::kMinimumAlignment) == 0"
")"); do { *((volatile int*)__null) = 1676; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1677
1678 char* table = reinterpret_cast<char*>(fake);
1679 if (table) {
1680 forEachSlot(table, aCapacity, [&](Slot& slot) {
1681 *slot.mKeyHash = sFreeKey;
1682 new (KnownNotNull, slot.toEntry()) Entry();
1683 });
1684 }
1685 return table;
1686 }
1687
1688 static void destroyTable(AllocPolicy& aAllocPolicy, char* aOldTable,
1689 uint32_t aCapacity) {
1690 forEachSlot(aOldTable, aCapacity, [&](const Slot& slot) {
1691 if (slot.isLive()) {
1692 slot.toEntry()->destroyStoredT();
1693 }
1694 });
1695 freeTable(aAllocPolicy, aOldTable, aCapacity);
20
Calling 'HashTable::freeTable'
26
Returning; memory was released via 2nd parameter
1696 }
1697
1698 static void freeTable(AllocPolicy& aAllocPolicy, char* aOldTable,
1699 uint32_t aCapacity) {
1700 FakeSlot* fake = reinterpret_cast<FakeSlot*>(aOldTable);
1701 aAllocPolicy.free_(fake, aCapacity);
21
Calling 'AllocPolicyBase::free_'
25
Returning; memory was released via 1st parameter
1702 }
1703
1704 public:
1705 HashTable(AllocPolicy aAllocPolicy, uint32_t aLen)
1706 : AllocPolicy(std::move(aAllocPolicy)),
1707 mGen(0),
1708 mHashShift(hashShift(aLen)),
1709 mTable(nullptr),
1710 mEntryCount(0),
1711 mRemovedCount(0)
1712#ifdef DEBUG1
1713 ,
1714 mMutationCount(0),
1715 mEntered(false)
1716#endif
1717 {
1718 }
1719
1720 explicit HashTable(AllocPolicy aAllocPolicy)
1721 : HashTable(aAllocPolicy, sDefaultLen) {}
1722
1723 ~HashTable() {
1724 if (mTable
35.1
Field 'mTable' is non-null
35.1
Field 'mTable' is non-null
35.1
Field 'mTable' is non-null
35.1
Field 'mTable' is non-null
35.1
Field 'mTable' is non-null
35.1
Field 'mTable' is non-null
35.1
Field 'mTable' is non-null
) {
17
Assuming field 'mTable' is non-null
18
Taking true branch
36
Taking true branch
1725 destroyTable(*this, mTable, capacity());
19
Calling 'HashTable::destroyTable'
27
Returning; memory was released via 2nd parameter
37
Use of memory after it is freed
1726 }
1727 }
1728
1729 private:
1730 HashNumber hash1(HashNumber aHash0) const { return aHash0 >> mHashShift; }
1731
1732 struct DoubleHash {
1733 HashNumber mHash2;
1734 HashNumber mSizeMask;
1735 };
1736
1737 DoubleHash hash2(HashNumber aCurKeyHash) const {
1738 uint32_t sizeLog2 = kHashNumberBits - mHashShift;
1739 DoubleHash dh = {((aCurKeyHash << sizeLog2) >> mHashShift) | 1,
1740 (HashNumber(1) << sizeLog2) - 1};
1741 return dh;
1742 }
1743
1744 static HashNumber applyDoubleHash(HashNumber aHash1,
1745 const DoubleHash& aDoubleHash) {
1746 return WrappingSubtract(aHash1, aDoubleHash.mHash2) & aDoubleHash.mSizeMask;
1747 }
1748
1749 static MOZ_ALWAYS_INLINEinline bool match(T& aEntry, const Lookup& aLookup) {
1750 return HashPolicy::match(HashPolicy::getKey(aEntry), aLookup);
1751 }
1752
1753 enum LookupReason { ForNonAdd, ForAdd };
1754
1755 Slot slotForIndex(HashNumber aIndex) const {
1756 auto hashes = reinterpret_cast<HashNumber*>(mTable);
1757 auto entries = reinterpret_cast<Entry*>(&hashes[capacity()]);
1758 return Slot(&entries[aIndex], &hashes[aIndex]);
1759 }
1760
1761 // Warning: in order for readonlyThreadsafeLookup() to be safe this
1762 // function must not modify the table in any way when Reason==ForNonAdd.
1763 template <LookupReason Reason>
1764 MOZ_ALWAYS_INLINEinline Slot lookup(const Lookup& aLookup,
1765 HashNumber aKeyHash) const {
1766 MOZ_ASSERT(isLiveHash(aKeyHash))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(isLiveHash(aKeyHash))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(isLiveHash(aKeyHash)))), 0))
) { do { } while (false); MOZ_ReportAssertionFailure("isLiveHash(aKeyHash)"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1766); AnnotateMozCrashReason("MOZ_ASSERT" "(" "isLiveHash(aKeyHash)"
")"); do { *((volatile int*)__null) = 1766; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1767 MOZ_ASSERT(!(aKeyHash & sCollisionBit))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!(aKeyHash & sCollisionBit))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!(aKeyHash & sCollisionBit
)))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("!(aKeyHash & sCollisionBit)", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1767); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!(aKeyHash & sCollisionBit)"
")"); do { *((volatile int*)__null) = 1767; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1768 MOZ_ASSERT(mTable)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mTable)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(mTable))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mTable", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1768); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mTable" ")"
); do { *((volatile int*)__null) = 1768; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1769
1770 // Compute the primary hash address.
1771 HashNumber h1 = hash1(aKeyHash);
1772 Slot slot = slotForIndex(h1);
1773
1774 // Miss: return space for a new entry.
1775 if (slot.isFree()) {
1776 return slot;
1777 }
1778
1779 // Hit: return entry.
1780 if (slot.matchHash(aKeyHash) && match(slot.get(), aLookup)) {
1781 return slot;
1782 }
1783
1784 // Collision: double hash.
1785 DoubleHash dh = hash2(aKeyHash);
1786
1787 // Save the first removed entry pointer so we can recycle later.
1788 Maybe<Slot> firstRemoved;
1789
1790 while (true) {
1791 if (Reason == ForAdd && !firstRemoved) {
1792 if (MOZ_UNLIKELY(slot.isRemoved())(__builtin_expect(!!(slot.isRemoved()), 0))) {
1793 firstRemoved.emplace(slot);
1794 } else {
1795 slot.setCollision();
1796 }
1797 }
1798
1799 h1 = applyDoubleHash(h1, dh);
1800
1801 slot = slotForIndex(h1);
1802 if (slot.isFree()) {
1803 return firstRemoved.refOr(slot);
1804 }
1805
1806 if (slot.matchHash(aKeyHash) && match(slot.get(), aLookup)) {
1807 return slot;
1808 }
1809 }
1810 }
1811
1812 // This is a copy of lookup() hardcoded to the assumptions:
1813 // 1. the lookup is for an add;
1814 // 2. the key, whose |keyHash| has been passed, is not in the table.
1815 Slot findNonLiveSlot(HashNumber aKeyHash) {
1816 MOZ_ASSERT(!(aKeyHash & sCollisionBit))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!(aKeyHash & sCollisionBit))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!(aKeyHash & sCollisionBit
)))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("!(aKeyHash & sCollisionBit)", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1816); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!(aKeyHash & sCollisionBit)"
")"); do { *((volatile int*)__null) = 1816; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1817 MOZ_ASSERT(mTable)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mTable)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(mTable))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mTable", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1817); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mTable" ")"
); do { *((volatile int*)__null) = 1817; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1818
1819 // We assume 'aKeyHash' has already been distributed.
1820
1821 // Compute the primary hash address.
1822 HashNumber h1 = hash1(aKeyHash);
1823 Slot slot = slotForIndex(h1);
1824
1825 // Miss: return space for a new entry.
1826 if (!slot.isLive()) {
1827 return slot;
1828 }
1829
1830 // Collision: double hash.
1831 DoubleHash dh = hash2(aKeyHash);
1832
1833 while (true) {
1834 slot.setCollision();
1835
1836 h1 = applyDoubleHash(h1, dh);
1837
1838 slot = slotForIndex(h1);
1839 if (!slot.isLive()) {
1840 return slot;
1841 }
1842 }
1843 }
1844
1845 enum RebuildStatus { NotOverloaded, Rehashed, RehashFailed };
1846
1847 RebuildStatus changeTableSize(
1848 uint32_t newCapacity, FailureBehavior aReportFailure = ReportFailure) {
1849 MOZ_ASSERT(IsPowerOfTwo(newCapacity))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(IsPowerOfTwo(newCapacity))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(IsPowerOfTwo(newCapacity))))
, 0))) { do { } while (false); MOZ_ReportAssertionFailure("IsPowerOfTwo(newCapacity)"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1849); AnnotateMozCrashReason("MOZ_ASSERT" "(" "IsPowerOfTwo(newCapacity)"
")"); do { *((volatile int*)__null) = 1849; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1850 MOZ_ASSERT(!!mTable == !!capacity())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!!mTable == !!capacity())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!!mTable == !!capacity()))),
0))) { do { } while (false); MOZ_ReportAssertionFailure("!!mTable == !!capacity()"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1850); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!!mTable == !!capacity()"
")"); do { *((volatile int*)__null) = 1850; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1851
1852 // Look, but don't touch, until we succeed in getting new entry store.
1853 char* oldTable = mTable;
1854 uint32_t oldCapacity = capacity();
1855 uint32_t newLog2 = mozilla::CeilingLog2(newCapacity);
1856
1857 if (MOZ_UNLIKELY(newCapacity > sMaxCapacity)(__builtin_expect(!!(newCapacity > sMaxCapacity), 0))) {
1858 if (aReportFailure) {
1859 this->reportAllocOverflow();
1860 }
1861 return RehashFailed;
1862 }
1863
1864 char* newTable = createTable(*this, newCapacity, aReportFailure);
1865 if (!newTable) {
1866 return RehashFailed;
1867 }
1868
1869 // We can't fail from here on, so update table parameters.
1870 mHashShift = kHashNumberBits - newLog2;
1871 mRemovedCount = 0;
1872 mGen++;
1873 mTable = newTable;
1874
1875 // Copy only live entries, leaving removed ones behind.
1876 forEachSlot(oldTable, oldCapacity, [&](Slot& slot) {
1877 if (slot.isLive()) {
1878 HashNumber hn = slot.getKeyHash();
1879 findNonLiveSlot(hn).setLive(
1880 hn, std::move(const_cast<typename Entry::NonConstT&>(slot.get())));
1881 }
1882
1883 slot.clear();
1884 });
1885
1886 // All entries have been destroyed, no need to destroyTable.
1887 freeTable(*this, oldTable, oldCapacity);
1888 return Rehashed;
1889 }
1890
1891 RebuildStatus rehashIfOverloaded(
1892 FailureBehavior aReportFailure = ReportFailure) {
1893 static_assert(sMaxCapacity <= UINT32_MAX(4294967295U) / sMaxAlphaNumerator,
1894 "multiplication below could overflow");
1895
1896 // Note: if capacity() is zero, this will always succeed, which is
1897 // what we want.
1898 bool overloaded = mEntryCount + mRemovedCount >=
1899 capacity() * sMaxAlphaNumerator / sAlphaDenominator;
1900
1901 if (!overloaded) {
1902 return NotOverloaded;
1903 }
1904
1905 // Succeed if a quarter or more of all entries are removed. Note that this
1906 // always succeeds if capacity() == 0 (i.e. entry storage has not been
1907 // allocated), which is what we want, because it means changeTableSize()
1908 // will allocate the requested capacity rather than doubling it.
1909 bool manyRemoved = mRemovedCount >= (capacity() >> 2);
1910 uint32_t newCapacity = manyRemoved ? rawCapacity() : rawCapacity() * 2;
1911 return changeTableSize(newCapacity, aReportFailure);
1912 }
1913
1914 void infallibleRehashIfOverloaded() {
1915 if (rehashIfOverloaded(DontReportFailure) == RehashFailed) {
1916 rehashTableInPlace();
1917 }
1918 }
1919
1920 void remove(Slot& aSlot) {
1921 MOZ_ASSERT(mTable)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mTable)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(mTable))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mTable", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1921); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mTable" ")"
); do { *((volatile int*)__null) = 1921; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1922
1923 if (aSlot.hasCollision()) {
1924 aSlot.removeLive();
1925 mRemovedCount++;
1926 } else {
1927 aSlot.clearLive();
1928 }
1929 mEntryCount--;
1930#ifdef DEBUG1
1931 mMutationCount++;
1932#endif
1933 }
1934
1935 void shrinkIfUnderloaded() {
1936 static_assert(sMaxCapacity <= UINT32_MAX(4294967295U) / sMinAlphaNumerator,
1937 "multiplication below could overflow");
1938 bool underloaded =
1939 capacity() > sMinCapacity &&
1940 mEntryCount <= capacity() * sMinAlphaNumerator / sAlphaDenominator;
1941
1942 if (underloaded) {
1943 (void)changeTableSize(capacity() / 2, DontReportFailure);
1944 }
1945 }
1946
1947 // This is identical to changeTableSize(currentSize), but without requiring
1948 // a second table. We do this by recycling the collision bits to tell us if
1949 // the element is already inserted or still waiting to be inserted. Since
1950 // already-inserted elements win any conflicts, we get the same table as we
1951 // would have gotten through random insertion order.
1952 void rehashTableInPlace() {
1953 mRemovedCount = 0;
1954 mGen++;
1955 forEachSlot(mTable, capacity(), [&](Slot& slot) { slot.unsetCollision(); });
1956 for (uint32_t i = 0; i < capacity();) {
1957 Slot src = slotForIndex(i);
1958
1959 if (!src.isLive() || src.hasCollision()) {
1960 ++i;
1961 continue;
1962 }
1963
1964 HashNumber keyHash = src.getKeyHash();
1965 HashNumber h1 = hash1(keyHash);
1966 DoubleHash dh = hash2(keyHash);
1967 Slot tgt = slotForIndex(h1);
1968 while (true) {
1969 if (!tgt.hasCollision()) {
1970 src.swap(tgt);
1971 tgt.setCollision();
1972 break;
1973 }
1974
1975 h1 = applyDoubleHash(h1, dh);
1976 tgt = slotForIndex(h1);
1977 }
1978 }
1979
1980 // TODO: this algorithm leaves collision bits on *all* elements, even if
1981 // they are on no collision path. We have the option of setting the
1982 // collision bits correctly on a subsequent pass or skipping the rehash
1983 // unless we are totally filled with tombstones: benchmark to find out
1984 // which approach is best.
1985 }
1986
1987 // Prefer to use putNewInfallible; this function does not check
1988 // invariants.
1989 template <typename... Args>
1990 void putNewInfallibleInternal(HashNumber aKeyHash, Args&&... aArgs) {
1991 MOZ_ASSERT(mTable)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(mTable)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(mTable))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mTable", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 1991); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mTable" ")"
); do { *((volatile int*)__null) = 1991; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
1992
1993 Slot slot = findNonLiveSlot(aKeyHash);
1994
1995 if (slot.isRemoved()) {
1996 mRemovedCount--;
1997 aKeyHash |= sCollisionBit;
1998 }
1999
2000 slot.setLive(aKeyHash, std::forward<Args>(aArgs)...);
2001 mEntryCount++;
2002#ifdef DEBUG1
2003 mMutationCount++;
2004#endif
2005 }
2006
2007 public:
2008 void clear() {
2009 forEachSlot(mTable, capacity(), [&](Slot& slot) { slot.clear(); });
2010 mRemovedCount = 0;
2011 mEntryCount = 0;
2012#ifdef DEBUG1
2013 mMutationCount++;
2014#endif
2015 }
2016
2017 // Resize the table down to the smallest capacity that doesn't overload the
2018 // table. Since we call shrinkIfUnderloaded() on every remove, you only need
2019 // to call this after a bulk removal of items done without calling remove().
2020 void compact() {
2021 if (empty()) {
2022 // Free the entry storage.
2023 freeTable(*this, mTable, capacity());
2024 mGen++;
2025 mHashShift = hashShift(0); // gives minimum capacity on regrowth
2026 mTable = nullptr;
2027 mRemovedCount = 0;
2028 return;
2029 }
2030
2031 uint32_t bestCapacity = this->bestCapacity(mEntryCount);
2032 MOZ_ASSERT(bestCapacity <= capacity())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(bestCapacity <= capacity())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(bestCapacity <= capacity(
)))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("bestCapacity <= capacity()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2032); AnnotateMozCrashReason("MOZ_ASSERT" "(" "bestCapacity <= capacity()"
")"); do { *((volatile int*)__null) = 2032; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2033
2034 if (bestCapacity < capacity()) {
2035 (void)changeTableSize(bestCapacity, DontReportFailure);
2036 }
2037 }
2038
2039 void clearAndCompact() {
2040 clear();
2041 compact();
2042 }
2043
2044 [[nodiscard]] bool reserve(uint32_t aLen) {
2045 if (aLen == 0) {
2046 return true;
2047 }
2048
2049 if (MOZ_UNLIKELY(aLen > sMaxInit)(__builtin_expect(!!(aLen > sMaxInit), 0))) {
2050 this->reportAllocOverflow();
2051 return false;
2052 }
2053
2054 uint32_t bestCapacity = this->bestCapacity(aLen);
2055 if (bestCapacity <= capacity()) {
2056 return true; // Capacity is already sufficient.
2057 }
2058
2059 RebuildStatus status = changeTableSize(bestCapacity, ReportFailure);
2060 MOZ_ASSERT(status != NotOverloaded)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(status != NotOverloaded)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(status != NotOverloaded))), 0
))) { do { } while (false); MOZ_ReportAssertionFailure("status != NotOverloaded"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2060); AnnotateMozCrashReason("MOZ_ASSERT" "(" "status != NotOverloaded"
")"); do { *((volatile int*)__null) = 2060; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2061 return status != RehashFailed;
2062 }
2063
2064 Iterator iter() const { return Iterator(*this); }
2065
2066 ModIterator modIter() { return ModIterator(*this); }
2067
2068 Range all() const { return Range(*this); }
2069
2070 bool empty() const { return mEntryCount == 0; }
2071
2072 uint32_t count() const { return mEntryCount; }
2073
2074 uint32_t rawCapacity() const { return 1u << (kHashNumberBits - mHashShift); }
2075
2076 uint32_t capacity() const { return mTable ? rawCapacity() : 0; }
2077
2078 Generation generation() const { return Generation(mGen); }
2079
2080 size_t shallowSizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
2081 return aMallocSizeOf(mTable);
2082 }
2083
2084 size_t shallowSizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
2085 return aMallocSizeOf(this) + shallowSizeOfExcludingThis(aMallocSizeOf);
2086 }
2087
2088 MOZ_ALWAYS_INLINEinline Ptr readonlyThreadsafeLookup(const Lookup& aLookup) const {
2089 if (empty()) {
2090 return Ptr();
2091 }
2092
2093 HashNumber inputHash;
2094 if (!MaybeGetHash<HashPolicy>(aLookup, &inputHash)) {
2095 return Ptr();
2096 }
2097
2098 HashNumber keyHash = prepareHash(inputHash);
2099 return Ptr(lookup<ForNonAdd>(aLookup, keyHash), *this);
2100 }
2101
2102 MOZ_ALWAYS_INLINEinline Ptr lookup(const Lookup& aLookup) const {
2103 ReentrancyGuard g(*this);
2104 return readonlyThreadsafeLookup(aLookup);
2105 }
2106
2107 MOZ_ALWAYS_INLINEinline AddPtr lookupForAdd(const Lookup& aLookup) {
2108 ReentrancyGuard g(*this);
2109
2110 HashNumber inputHash;
2111 if (!EnsureHash<HashPolicy>(aLookup, &inputHash)) {
2112 return AddPtr();
2113 }
2114
2115 HashNumber keyHash = prepareHash(inputHash);
2116
2117 if (!mTable) {
2118 return AddPtr(*this, keyHash);
2119 }
2120
2121 // Directly call the constructor in the return statement to avoid
2122 // excess copying when building with Visual Studio 2017.
2123 // See bug 1385181.
2124 return AddPtr(lookup<ForAdd>(aLookup, keyHash), *this, keyHash);
2125 }
2126
2127 template <typename... Args>
2128 [[nodiscard]] bool add(AddPtr& aPtr, Args&&... aArgs) {
2129 ReentrancyGuard g(*this);
2130 MOZ_ASSERT_IF(aPtr.isValid(), mTable)do { if (aPtr.isValid()) { do { static_assert( mozilla::detail
::AssertionConditionType<decltype(mTable)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(mTable))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("mTable", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2130); AnnotateMozCrashReason("MOZ_ASSERT" "(" "mTable" ")"
); do { *((volatile int*)__null) = 2130; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false); } } while (
false)
;
2131 MOZ_ASSERT_IF(aPtr.isValid(), aPtr.mTable == this)do { if (aPtr.isValid()) { do { static_assert( mozilla::detail
::AssertionConditionType<decltype(aPtr.mTable == this)>
::isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!(aPtr.mTable == this))), 0))) { do { } while (false);
MOZ_ReportAssertionFailure("aPtr.mTable == this", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2131); AnnotateMozCrashReason("MOZ_ASSERT" "(" "aPtr.mTable == this"
")"); do { *((volatile int*)__null) = 2131; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false); } } while (
false)
;
2132 MOZ_ASSERT(!aPtr.found())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!aPtr.found())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!aPtr.found()))), 0))) { do {
} while (false); MOZ_ReportAssertionFailure("!aPtr.found()",
"/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2132); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!aPtr.found()"
")"); do { *((volatile int*)__null) = 2132; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2133 MOZ_ASSERT(!(aPtr.mKeyHash & sCollisionBit))do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!(aPtr.mKeyHash & sCollisionBit))>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!(aPtr.mKeyHash & sCollisionBit
)))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("!(aPtr.mKeyHash & sCollisionBit)", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2133); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!(aPtr.mKeyHash & sCollisionBit)"
")"); do { *((volatile int*)__null) = 2133; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2134
2135 // Check for error from ensureHash() here.
2136 if (!aPtr.isLive()) {
2137 return false;
2138 }
2139
2140 MOZ_ASSERT(aPtr.mGeneration == generation())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(aPtr.mGeneration == generation())>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(aPtr.mGeneration == generation
()))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("aPtr.mGeneration == generation()", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2140); AnnotateMozCrashReason("MOZ_ASSERT" "(" "aPtr.mGeneration == generation()"
")"); do { *((volatile int*)__null) = 2140; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2141#ifdef DEBUG1
2142 MOZ_ASSERT(aPtr.mMutationCount == mMutationCount)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(aPtr.mMutationCount == mMutationCount)>::isValid,
"invalid assertion condition"); if ((__builtin_expect(!!(!(!
!(aPtr.mMutationCount == mMutationCount))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("aPtr.mMutationCount == mMutationCount"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2142); AnnotateMozCrashReason("MOZ_ASSERT" "(" "aPtr.mMutationCount == mMutationCount"
")"); do { *((volatile int*)__null) = 2142; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2143#endif
2144
2145 if (!aPtr.isValid()) {
2146 MOZ_ASSERT(!mTable && mEntryCount == 0)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!mTable && mEntryCount == 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(!mTable && mEntryCount
== 0))), 0))) { do { } while (false); MOZ_ReportAssertionFailure
("!mTable && mEntryCount == 0", "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2146); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!mTable && mEntryCount == 0"
")"); do { *((volatile int*)__null) = 2146; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2147 uint32_t newCapacity = rawCapacity();
2148 RebuildStatus status = changeTableSize(newCapacity, ReportFailure);
2149 MOZ_ASSERT(status != NotOverloaded)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(status != NotOverloaded)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(status != NotOverloaded))), 0
))) { do { } while (false); MOZ_ReportAssertionFailure("status != NotOverloaded"
, "/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/mozilla/HashTable.h"
, 2149); AnnotateMozCrashReason("MOZ_ASSERT" "(" "status != NotOverloaded"
")"); do { *((volatile int*)__null) = 2149; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false)
;
2150 if (status == RehashFailed) {
2151 return false;
2152 }
2153 aPtr.mSlot = findNonLiveSlot(aPtr.mKeyHash);
2154
2155 } else if (aPtr.mSlot.isRemoved()) {
2156 // Changing an entry from removed to live does not affect whether we are
2157 // overloaded and can be handled separately.
2158 if (!this->checkSimulatedOOM()) {
2159 return false;
2160 }
2161 mRemovedCount--;
2162 aPtr.mKeyHash |= sCollisionBit;
2163
2164 } else {
2165 // Preserve the validity of |aPtr.mSlot|.
2166 RebuildSt