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Copied from https://hg.mozilla.org/releases/mozilla-esr38/raw-rev/71f611fd27c7
# HG changeset patch
# User Jeff Walden <jwalden@mit.edu>
# Date 1458941573 25200
# Node ID 71f611fd27c7d6cb7d6dab9895c2922948042543
# Parent 861f6b83ce1deade2a976cabe059776ad51ce370
Bug 1246061. r=luke, r=froydnj, a=sylvestre
diff --git a/js/public/HashTable.h b/js/public/HashTable.h
--- a/js/public/HashTable.h
+++ b/js/public/HashTable.h
@@ -8,16 +8,17 @@
#define js_HashTable_h
#include "mozilla/Alignment.h"
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/Casting.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Move.h"
+#include "mozilla/Opaque.h"
#include "mozilla/PodOperations.h"
#include "mozilla/ReentrancyGuard.h"
#include "mozilla/TemplateLib.h"
#include "mozilla/TypeTraits.h"
#include "js/Utility.h"
namespace js {
@@ -27,16 +28,18 @@ template <class> struct DefaultHasher;
template <class, class> class HashMapEntry;
namespace detail {
template <class T> class HashTableEntry;
template <class T, class HashPolicy, class AllocPolicy> class HashTable;
}
/*****************************************************************************/
+using Generation = mozilla::Opaque<uint64_t>;
+
// A JS-friendly, STL-like container providing a hash-based map from keys to
// values. In particular, HashMap calls constructors and destructors of all
// objects added so non-PODs may be used safely.
//
// Key/Value requirements:
// - movable, destructible, assignable
// HashPolicy requirements:
// - see Hash Policy section below
@@ -200,17 +203,19 @@ class HashMap
return impl.sizeOfExcludingThis(mallocSizeOf);
}
size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return mallocSizeOf(this) + impl.sizeOfExcludingThis(mallocSizeOf);
}
// If |generation()| is the same before and after a HashMap operation,
// pointers into the table remain valid.
- uint32_t generation() const { return impl.generation(); }
+ Generation generation() const {
+ return impl.generation();
+ }
/************************************************** Shorthand operations */
bool has(const Lookup& l) const {
return impl.lookup(l).found();
}
// Overwrite existing value with v. Return false on oom.
@@ -431,17 +436,19 @@ class HashSet
return impl.sizeOfExcludingThis(mallocSizeOf);
}
size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return mallocSizeOf(this) + impl.sizeOfExcludingThis(mallocSizeOf);
}
// If |generation()| is the same before and after a HashSet operation,
// pointers into the table remain valid.
- uint32_t generation() const { return impl.generation(); }
+ Generation generation() const {
+ return impl.generation();
+ }
/************************************************** Shorthand operations */
bool has(const Lookup& l) const {
return impl.lookup(l).found();
}
// Add |u| if it is not present already. Return false on oom.
@@ -766,17 +773,17 @@ class HashTable : private AllocPolicy
// table operations unless |generation()| is tested.
class Ptr
{
friend class HashTable;
Entry* entry_;
#ifdef JS_DEBUG
const HashTable* table_;
- uint32_t generation;
+ Generation generation;
#endif
protected:
Ptr(Entry& entry, const HashTable& tableArg)
: entry_(&entry)
#ifdef JS_DEBUG
, table_(&tableArg)
, generation(tableArg.generation())
@@ -873,17 +880,17 @@ class HashTable : private AllocPolicy
while (cur < end && !cur->isLive())
++cur;
}
Entry* cur, *end;
#ifdef JS_DEBUG
const HashTable* table_;
uint64_t mutationCount;
- uint32_t generation;
+ Generation generation;
bool validEntry;
#endif
public:
Range()
: cur(nullptr)
, end(nullptr)
#ifdef JS_DEBUG
@@ -1012,18 +1019,18 @@ class HashTable : private AllocPolicy
// HashTable is not copyable or assignable
HashTable(const HashTable&) = delete;
void operator=(const HashTable&) = delete;
private:
static const size_t CAP_BITS = 24;
public:
- Entry* table; // entry storage
- uint32_t gen; // entry storage generation number
+ uint64_t gen; // entry storage generation number
+ Entry* table; // entry storage
uint32_t entryCount; // number of entries in table
uint32_t removedCount:CAP_BITS; // removed entry sentinels in table
uint32_t hashShift:8; // multiplicative hash shift
#ifdef JS_DEBUG
uint64_t mutationCount;
mutable bool mEntered;
mutable struct Stats
@@ -1097,18 +1104,18 @@ class HashTable : private AllocPolicy
for (Entry* e = oldTable, *end = e + capacity; e < end; ++e)
e->destroyIfLive();
alloc.free_(oldTable);
}
public:
explicit HashTable(AllocPolicy ap)
: AllocPolicy(ap)
+ , gen(0)
, table(nullptr)
- , gen(0)
, entryCount(0)
, removedCount(0)
, hashShift(sHashBits)
#ifdef JS_DEBUG
, mutationCount(0)
, mEntered(false)
#endif
{}
@@ -1524,20 +1531,20 @@ class HashTable : private AllocPolicy
}
uint32_t capacity() const
{
MOZ_ASSERT(table);
return JS_BIT(sHashBits - hashShift);
}
- uint32_t generation() const
+ Generation generation() const
{
MOZ_ASSERT(table);
- return gen;
+ return Generation(gen);
}
size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const
{
return mallocSizeOf(table);
}
size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const
diff --git a/js/src/jsapi.h b/js/src/jsapi.h
--- a/js/src/jsapi.h
+++ b/js/src/jsapi.h
@@ -270,20 +270,16 @@ class AutoHashMapRooter : protected Auto
size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return map.sizeOfExcludingThis(mallocSizeOf);
}
size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return map.sizeOfIncludingThis(mallocSizeOf);
}
- uint32_t generation() const {
- return map.generation();
- }
-
/************************************************** Shorthand operations */
bool has(const Lookup& l) const {
return map.has(l);
}
template<typename KeyInput, typename ValueInput>
bool put(const KeyInput& k, const ValueInput& v) {
@@ -385,20 +381,16 @@ class AutoHashSetRooter : protected Auto
size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return set.sizeOfExcludingThis(mallocSizeOf);
}
size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
return set.sizeOfIncludingThis(mallocSizeOf);
}
- uint32_t generation() const {
- return set.generation();
- }
-
/************************************************** Shorthand operations */
bool has(const Lookup& l) const {
return set.has(l);
}
bool put(const T& t) {
return set.put(t);
diff --git a/js/src/jscntxt.h b/js/src/jscntxt.h
--- a/js/src/jscntxt.h
+++ b/js/src/jscntxt.h
@@ -30,21 +30,21 @@ class DebugModeOSRVolatileJitFrameIterat
}
typedef HashSet<JSObject*> ObjectSet;
typedef HashSet<Shape*> ShapeSet;
/* Detects cycles when traversing an object graph. */
class AutoCycleDetector
{
+ Generation hashsetGenerationAtInit;
JSContext* cx;
RootedObject obj;
+ ObjectSet::AddPtr hashsetAddPointer;
bool cyclic;
- uint32_t hashsetGenerationAtInit;
- ObjectSet::AddPtr hashsetAddPointer;
MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
public:
AutoCycleDetector(JSContext* cx, HandleObject objArg
MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
: cx(cx), obj(cx, objArg), cyclic(true)
{
MOZ_GUARD_OBJECT_NOTIFIER_INIT;
diff --git a/js/src/jswatchpoint.cpp b/js/src/jswatchpoint.cpp
--- a/js/src/jswatchpoint.cpp
+++ b/js/src/jswatchpoint.cpp
@@ -22,25 +22,25 @@ DefaultHasher<WatchKey>::hash(const Look
{
return DefaultHasher<JSObject*>::hash(key.object.get()) ^ HashId(key.id.get());
}
namespace {
class AutoEntryHolder {
typedef WatchpointMap::Map Map;
+ Generation gen;
Map& map;
Map::Ptr p;
- uint32_t gen;
RootedObject obj;
RootedId id;
public:
AutoEntryHolder(JSContext* cx, Map& map, Map::Ptr p)
- : map(map), p(p), gen(map.generation()), obj(cx, p->key().object), id(cx, p->key().id)
+ : gen(map.generation()), map(map), p(p), obj(cx, p->key().object), id(cx, p->key().id)
{
MOZ_ASSERT(!p->value().held);
p->value().held = true;
}
~AutoEntryHolder() {
if (gen != map.generation())
p = map.lookup(WatchKey(obj, id));
diff --git a/js/src/shell/jsheaptools.cpp b/js/src/shell/jsheaptools.cpp
--- a/js/src/shell/jsheaptools.cpp
+++ b/js/src/shell/jsheaptools.cpp
@@ -267,17 +267,17 @@ HeapReverser::traverseEdge(void* cell, J
Map::AddPtr a = map.lookupForAdd(cell);
if (!a) {
/*
* We've never visited this cell before. Add it to the map (thus
* marking it as visited), and put it on the work stack, to be
* visited from the main loop.
*/
Node n(kind);
- uint32_t generation = map.generation();
+ Generation generation = map.generation();
if (!map.add(a, cell, Move(n)) ||
!work.append(Child(cell, kind)))
return false;
/* If the map has been resized, re-check the pointer. */
if (map.generation() != generation)
a = map.lookupForAdd(cell);
}
diff --git a/mfbt/Opaque.h b/mfbt/Opaque.h
new file mode 100644
--- /dev/null
+++ b/mfbt/Opaque.h
@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* An opaque integral type supporting only comparison operators. */
+
+#ifndef mozilla_Opaque_h
+#define mozilla_Opaque_h
+
+#include "mozilla/TypeTraits.h"
+
+namespace mozilla {
+
+/**
+ * Opaque<T> is a replacement for integral T in cases where only comparisons
+ * must be supported, and it's desirable to prevent accidental dependency on
+ * exact values.
+ */
+template<typename T>
+class Opaque final
+{
+ static_assert(mozilla::IsIntegral<T>::value,
+ "mozilla::Opaque only supports integral types");
+
+ T mValue;
+
+public:
+ Opaque() {}
+ explicit Opaque(T aValue) : mValue(aValue) {}
+
+ bool operator==(const Opaque& aOther) const {
+ return mValue == aOther.mValue;
+ }
+
+ bool operator!=(const Opaque& aOther) const {
+ return !(*this == aOther);
+ }
+};
+
+} // namespace mozilla
+
+#endif /* mozilla_Opaque_h */
diff --git a/mfbt/moz.build b/mfbt/moz.build
--- a/mfbt/moz.build
+++ b/mfbt/moz.build
@@ -48,16 +48,17 @@ EXPORTS.mozilla = [
'MathAlgorithms.h',
'Maybe.h',
'MaybeOneOf.h',
'MemoryChecking.h',
'MemoryReporting.h',
'Move.h',
'NullPtr.h',
'NumericLimits.h',
+ 'Opaque.h',
'Pair.h',
'PodOperations.h',
'Poison.h',
'Range.h',
'RangedPtr.h',
'RefCountType.h',
'ReentrancyGuard.h',
'RefPtr.h',
|