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// Copyright 2006-2008 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef V8_STUB_CACHE_H_
#define V8_STUB_CACHE_H_
#include "macro-assembler.h"
namespace v8 {
namespace internal {
// The stub cache is used for megamorphic calls and property accesses.
// It maps (map, name, type)->Code*
// The design of the table uses the inline cache stubs used for
// mono-morphic calls. The beauty of this, we do not have to
// invalidate the cache whenever a prototype map is changed. The stub
// validates the map chain as in the mono-morphic case.
class SCTableReference;
class StubCache : public AllStatic {
public:
struct Entry {
String* key;
Code* value;
};
static void Initialize(bool create_heap_objects);
// Computes the right stub matching. Inserts the result in the
// cache before returning. This might compile a stub if needed.
MUST_USE_RESULT static MaybeObject* ComputeLoadNonexistent(
String* name,
JSObject* receiver);
MUST_USE_RESULT static MaybeObject* ComputeLoadField(String* name,
JSObject* receiver,
JSObject* holder,
int field_index);
MUST_USE_RESULT static MaybeObject* ComputeLoadCallback(
String* name,
JSObject* receiver,
JSObject* holder,
AccessorInfo* callback);
MUST_USE_RESULT static MaybeObject* ComputeLoadConstant(String* name,
JSObject* receiver,
JSObject* holder,
Object* value);
MUST_USE_RESULT static MaybeObject* ComputeLoadInterceptor(String* name,
JSObject* receiver,
JSObject* holder);
MUST_USE_RESULT static MaybeObject* ComputeLoadNormal();
MUST_USE_RESULT static MaybeObject* ComputeLoadGlobal(
String* name,
JSObject* receiver,
GlobalObject* holder,
JSGlobalPropertyCell* cell,
bool is_dont_delete);
// ---
MUST_USE_RESULT static MaybeObject* ComputeKeyedLoadField(String* name,
JSObject* receiver,
JSObject* holder,
int field_index);
MUST_USE_RESULT static MaybeObject* ComputeKeyedLoadCallback(
String* name,
JSObject* receiver,
JSObject* holder,
AccessorInfo* callback);
MUST_USE_RESULT static MaybeObject* ComputeKeyedLoadConstant(
String* name,
JSObject* receiver,
JSObject* holder,
Object* value);
MUST_USE_RESULT static MaybeObject* ComputeKeyedLoadInterceptor(
String* name,
JSObject* receiver,
JSObject* holder);
MUST_USE_RESULT static MaybeObject* ComputeKeyedLoadArrayLength(
String* name,
JSArray* receiver);
MUST_USE_RESULT static MaybeObject* ComputeKeyedLoadStringLength(
String* name,
String* receiver);
MUST_USE_RESULT static MaybeObject* ComputeKeyedLoadFunctionPrototype(
String* name,
JSFunction* receiver);
// ---
MUST_USE_RESULT static MaybeObject* ComputeStoreField(String* name,
JSObject* receiver,
int field_index,
Map* transition = NULL);
MUST_USE_RESULT static MaybeObject* ComputeStoreNormal();
MUST_USE_RESULT static MaybeObject* ComputeStoreGlobal(
String* name,
GlobalObject* receiver,
JSGlobalPropertyCell* cell);
MUST_USE_RESULT static MaybeObject* ComputeStoreCallback(
String* name,
JSObject* receiver,
AccessorInfo* callback);
MUST_USE_RESULT static MaybeObject* ComputeStoreInterceptor(
String* name,
JSObject* receiver);
// ---
MUST_USE_RESULT static MaybeObject* ComputeKeyedStoreField(
String* name,
JSObject* receiver,
int field_index,
Map* transition = NULL);
// ---
MUST_USE_RESULT static MaybeObject* ComputeCallField(int argc,
InLoopFlag in_loop,
Code::Kind,
String* name,
Object* object,
JSObject* holder,
int index);
MUST_USE_RESULT static MaybeObject* ComputeCallConstant(int argc,
InLoopFlag in_loop,
Code::Kind,
String* name,
Object* object,
JSObject* holder,
JSFunction* function);
MUST_USE_RESULT static MaybeObject* ComputeCallNormal(int argc,
InLoopFlag in_loop,
Code::Kind,
String* name,
JSObject* receiver);
MUST_USE_RESULT static MaybeObject* ComputeCallInterceptor(int argc,
Code::Kind,
String* name,
Object* object,
JSObject* holder);
MUST_USE_RESULT static MaybeObject* ComputeCallGlobal(
int argc,
InLoopFlag in_loop,
Code::Kind,
String* name,
JSObject* receiver,
GlobalObject* holder,
JSGlobalPropertyCell* cell,
JSFunction* function);
// ---
MUST_USE_RESULT static MaybeObject* ComputeCallInitialize(int argc,
InLoopFlag in_loop,
Code::Kind kind);
static Handle<Code> ComputeCallInitialize(int argc, InLoopFlag in_loop);
static Handle<Code> ComputeKeyedCallInitialize(int argc, InLoopFlag in_loop);
MUST_USE_RESULT static MaybeObject* ComputeCallPreMonomorphic(
int argc,
InLoopFlag in_loop,
Code::Kind kind);
MUST_USE_RESULT static MaybeObject* ComputeCallNormal(int argc,
InLoopFlag in_loop,
Code::Kind kind);
MUST_USE_RESULT static MaybeObject* ComputeCallMegamorphic(int argc,
InLoopFlag in_loop,
Code::Kind kind);
MUST_USE_RESULT static MaybeObject* ComputeCallMiss(int argc,
Code::Kind kind);
// Finds the Code object stored in the Heap::non_monomorphic_cache().
MUST_USE_RESULT static Code* FindCallInitialize(int argc,
InLoopFlag in_loop,
Code::Kind kind);
#ifdef ENABLE_DEBUGGER_SUPPORT
MUST_USE_RESULT static MaybeObject* ComputeCallDebugBreak(int argc,
Code::Kind kind);
MUST_USE_RESULT static MaybeObject* ComputeCallDebugPrepareStepIn(
int argc,
Code::Kind kind);
#endif
// Update cache for entry hash(name, map).
static Code* Set(String* name, Map* map, Code* code);
// Clear the lookup table (@ mark compact collection).
static void Clear();
// Generate code for probing the stub cache table.
// Arguments extra and extra2 may be used to pass additional scratch
// registers. Set to no_reg if not needed.
static void GenerateProbe(MacroAssembler* masm,
Code::Flags flags,
Register receiver,
Register name,
Register scratch,
Register extra,
Register extra2 = no_reg);
enum Table {
kPrimary,
kSecondary
};
private:
friend class SCTableReference;
static const int kPrimaryTableSize = 2048;
static const int kSecondaryTableSize = 512;
static Entry primary_[];
static Entry secondary_[];
// Computes the hashed offsets for primary and secondary caches.
static int PrimaryOffset(String* name, Code::Flags flags, Map* map) {
// This works well because the heap object tag size and the hash
// shift are equal. Shifting down the length field to get the
// hash code would effectively throw away two bits of the hash
// code.
ASSERT(kHeapObjectTagSize == String::kHashShift);
// Compute the hash of the name (use entire hash field).
ASSERT(name->HasHashCode());
uint32_t field = name->hash_field();
// Using only the low bits in 64-bit mode is unlikely to increase the
// risk of collision even if the heap is spread over an area larger than
// 4Gb (and not at all if it isn't).
uint32_t map_low32bits =
static_cast<uint32_t>(reinterpret_cast<uintptr_t>(map));
// We always set the in_loop bit to zero when generating the lookup code
// so do it here too so the hash codes match.
uint32_t iflags =
(static_cast<uint32_t>(flags) & ~Code::kFlagsNotUsedInLookup);
// Base the offset on a simple combination of name, flags, and map.
uint32_t key = (map_low32bits + field) ^ iflags;
return key & ((kPrimaryTableSize - 1) << kHeapObjectTagSize);
}
static int SecondaryOffset(String* name, Code::Flags flags, int seed) {
// Use the seed from the primary cache in the secondary cache.
uint32_t string_low32bits =
static_cast<uint32_t>(reinterpret_cast<uintptr_t>(name));
// We always set the in_loop bit to zero when generating the lookup code
// so do it here too so the hash codes match.
uint32_t iflags =
(static_cast<uint32_t>(flags) & ~Code::kFlagsICInLoopMask);
uint32_t key = seed - string_low32bits + iflags;
return key & ((kSecondaryTableSize - 1) << kHeapObjectTagSize);
}
// Compute the entry for a given offset in exactly the same way as
// we do in generated code. We generate an hash code that already
// ends in String::kHashShift 0s. Then we shift it so it is a multiple
// of sizeof(Entry). This makes it easier to avoid making mistakes
// in the hashed offset computations.
static Entry* entry(Entry* table, int offset) {
const int shift_amount = kPointerSizeLog2 + 1 - String::kHashShift;
return reinterpret_cast<Entry*>(
reinterpret_cast<Address>(table) + (offset << shift_amount));
}
};
class SCTableReference {
public:
static SCTableReference keyReference(StubCache::Table table) {
return SCTableReference(
reinterpret_cast<Address>(&first_entry(table)->key));
}
static SCTableReference valueReference(StubCache::Table table) {
return SCTableReference(
reinterpret_cast<Address>(&first_entry(table)->value));
}
Address address() const { return address_; }
private:
explicit SCTableReference(Address address) : address_(address) {}
static StubCache::Entry* first_entry(StubCache::Table table) {
switch (table) {
case StubCache::kPrimary: return StubCache::primary_;
case StubCache::kSecondary: return StubCache::secondary_;
}
UNREACHABLE();
return NULL;
}
Address address_;
};
// ------------------------------------------------------------------------
// Support functions for IC stubs for callbacks.
MaybeObject* LoadCallbackProperty(Arguments args);
MaybeObject* StoreCallbackProperty(Arguments args);
// Support functions for IC stubs for interceptors.
MaybeObject* LoadPropertyWithInterceptorOnly(Arguments args);
MaybeObject* LoadPropertyWithInterceptorForLoad(Arguments args);
MaybeObject* LoadPropertyWithInterceptorForCall(Arguments args);
MaybeObject* StoreInterceptorProperty(Arguments args);
MaybeObject* CallInterceptorProperty(Arguments args);
MaybeObject* KeyedLoadPropertyWithInterceptor(Arguments args);
// The stub compiler compiles stubs for the stub cache.
class StubCompiler BASE_EMBEDDED {
public:
enum CheckType {
RECEIVER_MAP_CHECK,
STRING_CHECK,
NUMBER_CHECK,
BOOLEAN_CHECK
};
StubCompiler() : scope_(), masm_(NULL, 256), failure_(NULL) { }
MUST_USE_RESULT MaybeObject* CompileCallInitialize(Code::Flags flags);
MUST_USE_RESULT MaybeObject* CompileCallPreMonomorphic(Code::Flags flags);
MUST_USE_RESULT MaybeObject* CompileCallNormal(Code::Flags flags);
MUST_USE_RESULT MaybeObject* CompileCallMegamorphic(Code::Flags flags);
MUST_USE_RESULT MaybeObject* CompileCallMiss(Code::Flags flags);
#ifdef ENABLE_DEBUGGER_SUPPORT
MUST_USE_RESULT MaybeObject* CompileCallDebugBreak(Code::Flags flags);
MUST_USE_RESULT MaybeObject* CompileCallDebugPrepareStepIn(Code::Flags flags);
#endif
// Static functions for generating parts of stubs.
static void GenerateLoadGlobalFunctionPrototype(MacroAssembler* masm,
int index,
Register prototype);
// Generates prototype loading code that uses the objects from the
// context we were in when this function was called. If the context
// has changed, a jump to miss is performed. This ties the generated
// code to a particular context and so must not be used in cases
// where the generated code is not allowed to have references to
// objects from a context.
static void GenerateDirectLoadGlobalFunctionPrototype(MacroAssembler* masm,
int index,
Register prototype,
Label* miss);
static void GenerateFastPropertyLoad(MacroAssembler* masm,
Register dst, Register src,
JSObject* holder, int index);
static void GenerateLoadArrayLength(MacroAssembler* masm,
Register receiver,
Register scratch,
Label* miss_label);
static void GenerateLoadStringLength(MacroAssembler* masm,
Register receiver,
Register scratch1,
Register scratch2,
Label* miss_label);
static void GenerateLoadFunctionPrototype(MacroAssembler* masm,
Register receiver,
Register scratch1,
Register scratch2,
Label* miss_label);
static void GenerateStoreField(MacroAssembler* masm,
JSObject* object,
int index,
Map* transition,
Register receiver_reg,
Register name_reg,
Register scratch,
Label* miss_label);
static void GenerateLoadMiss(MacroAssembler* masm, Code::Kind kind);
// Generates code that verifies that the property holder has not changed
// (checking maps of objects in the prototype chain for fast and global
// objects or doing negative lookup for slow objects, ensures that the
// property cells for global objects are still empty) and checks that the map
// of the holder has not changed. If necessary the function also generates
// code for security check in case of global object holders. Helps to make
// sure that the current IC is still valid.
//
// The scratch and holder registers are always clobbered, but the object
// register is only clobbered if it the same as the holder register. The
// function returns a register containing the holder - either object_reg or
// holder_reg.
// The function can optionally (when save_at_depth !=
// kInvalidProtoDepth) save the object at the given depth by moving
// it to [esp + kPointerSize].
Register CheckPrototypes(JSObject* object,
Register object_reg,
JSObject* holder,
Register holder_reg,
Register scratch1,
Register scratch2,
String* name,
Label* miss) {
return CheckPrototypes(object, object_reg, holder, holder_reg, scratch1,
scratch2, name, kInvalidProtoDepth, miss);
}
Register CheckPrototypes(JSObject* object,
Register object_reg,
JSObject* holder,
Register holder_reg,
Register scratch1,
Register scratch2,
String* name,
int save_at_depth,
Label* miss);
protected:
MaybeObject* GetCodeWithFlags(Code::Flags flags, const char* name);
MaybeObject* GetCodeWithFlags(Code::Flags flags, String* name);
MacroAssembler* masm() { return &masm_; }
void set_failure(Failure* failure) { failure_ = failure; }
void GenerateLoadField(JSObject* object,
JSObject* holder,
Register receiver,
Register scratch1,
Register scratch2,
Register scratch3,
int index,
String* name,
Label* miss);
bool GenerateLoadCallback(JSObject* object,
JSObject* holder,
Register receiver,
Register name_reg,
Register scratch1,
Register scratch2,
Register scratch3,
AccessorInfo* callback,
String* name,
Label* miss,
Failure** failure);
void GenerateLoadConstant(JSObject* object,
JSObject* holder,
Register receiver,
Register scratch1,
Register scratch2,
Register scratch3,
Object* value,
String* name,
Label* miss);
void GenerateLoadInterceptor(JSObject* object,
JSObject* holder,
LookupResult* lookup,
Register receiver,
Register name_reg,
Register scratch1,
Register scratch2,
Register scratch3,
String* name,
Label* miss);
static void LookupPostInterceptor(JSObject* holder,
String* name,
LookupResult* lookup);
private:
HandleScope scope_;
MacroAssembler masm_;
Failure* failure_;
};
class LoadStubCompiler: public StubCompiler {
public:
MUST_USE_RESULT MaybeObject* CompileLoadNonexistent(String* name,
JSObject* object,
JSObject* last);
MUST_USE_RESULT MaybeObject* CompileLoadField(JSObject* object,
JSObject* holder,
int index,
String* name);
MUST_USE_RESULT MaybeObject* CompileLoadCallback(String* name,
JSObject* object,
JSObject* holder,
AccessorInfo* callback);
MUST_USE_RESULT MaybeObject* CompileLoadConstant(JSObject* object,
JSObject* holder,
Object* value,
String* name);
MUST_USE_RESULT MaybeObject* CompileLoadInterceptor(JSObject* object,
JSObject* holder,
String* name);
MUST_USE_RESULT MaybeObject* CompileLoadGlobal(JSObject* object,
GlobalObject* holder,
JSGlobalPropertyCell* cell,
String* name,
bool is_dont_delete);
private:
MaybeObject* GetCode(PropertyType type, String* name);
};
class KeyedLoadStubCompiler: public StubCompiler {
public:
MUST_USE_RESULT MaybeObject* CompileLoadField(String* name,
JSObject* object,
JSObject* holder,
int index);
MUST_USE_RESULT MaybeObject* CompileLoadCallback(String* name,
JSObject* object,
JSObject* holder,
AccessorInfo* callback);
MUST_USE_RESULT MaybeObject* CompileLoadConstant(String* name,
JSObject* object,
JSObject* holder,
Object* value);
MUST_USE_RESULT MaybeObject* CompileLoadInterceptor(JSObject* object,
JSObject* holder,
String* name);
MUST_USE_RESULT MaybeObject* CompileLoadArrayLength(String* name);
MUST_USE_RESULT MaybeObject* CompileLoadStringLength(String* name);
MUST_USE_RESULT MaybeObject* CompileLoadFunctionPrototype(String* name);
private:
MaybeObject* GetCode(PropertyType type, String* name);
};
class StoreStubCompiler: public StubCompiler {
public:
MUST_USE_RESULT MaybeObject* CompileStoreField(JSObject* object,
int index,
Map* transition,
String* name);
MUST_USE_RESULT MaybeObject* CompileStoreCallback(JSObject* object,
AccessorInfo* callbacks,
String* name);
MUST_USE_RESULT MaybeObject* CompileStoreInterceptor(JSObject* object,
String* name);
MUST_USE_RESULT MaybeObject* CompileStoreGlobal(GlobalObject* object,
JSGlobalPropertyCell* holder,
String* name);
private:
MUST_USE_RESULT MaybeObject* GetCode(PropertyType type, String* name);
};
class KeyedStoreStubCompiler: public StubCompiler {
public:
MaybeObject* CompileStoreField(JSObject* object,
int index,
Map* transition,
String* name);
private:
MaybeObject* GetCode(PropertyType type, String* name);
};
// List of functions with custom constant call IC stubs.
//
// Installation of custom call generators for the selected builtins is
// handled by the bootstrapper.
//
// Each entry has a name of a global object property holding an object
// optionally followed by ".prototype" (this controls whether the
// generator is set on the object itself or, in case it's a function,
// on the its instance prototype), a name of a builtin function on the
// object (the one the generator is set for), and a name of the
// generator (used to build ids and generator function names).
#define CUSTOM_CALL_IC_GENERATORS(V) \
V(Array.prototype, push, ArrayPush) \
V(Array.prototype, pop, ArrayPop) \
V(String.prototype, charCodeAt, StringCharCodeAt) \
V(String.prototype, charAt, StringCharAt) \
V(String, fromCharCode, StringFromCharCode) \
V(Math, floor, MathFloor) \
V(Math, abs, MathAbs)
class CallStubCompiler: public StubCompiler {
public:
enum {
#define DECLARE_CALL_GENERATOR_ID(ignored1, ignore2, name) \
k##name##CallGenerator,
CUSTOM_CALL_IC_GENERATORS(DECLARE_CALL_GENERATOR_ID)
#undef DECLARE_CALL_GENERATOR_ID
kNumCallGenerators
};
CallStubCompiler(int argc,
InLoopFlag in_loop,
Code::Kind kind,
InlineCacheHolderFlag cache_holder);
MUST_USE_RESULT MaybeObject* CompileCallField(JSObject* object,
JSObject* holder,
int index,
String* name);
MUST_USE_RESULT MaybeObject* CompileCallConstant(Object* object,
JSObject* holder,
JSFunction* function,
String* name,
CheckType check);
MUST_USE_RESULT MaybeObject* CompileCallInterceptor(JSObject* object,
JSObject* holder,
String* name);
MUST_USE_RESULT MaybeObject* CompileCallGlobal(JSObject* object,
GlobalObject* holder,
JSGlobalPropertyCell* cell,
JSFunction* function,
String* name);
// Compiles a custom call constant/global IC using the generator
// with given id. For constant calls cell is NULL.
MUST_USE_RESULT MaybeObject* CompileCustomCall(int generator_id,
Object* object,
JSObject* holder,
JSGlobalPropertyCell* cell,
JSFunction* function,
String* name);
#define DECLARE_CALL_GENERATOR(ignored1, ignored2, name) \
MUST_USE_RESULT MaybeObject* Compile##name##Call(Object* object, \
JSObject* holder, \
JSGlobalPropertyCell* cell, \
JSFunction* function, \
String* fname);
CUSTOM_CALL_IC_GENERATORS(DECLARE_CALL_GENERATOR)
#undef DECLARE_CALL_GENERATOR
private:
const ParameterCount arguments_;
const InLoopFlag in_loop_;
const Code::Kind kind_;
const InlineCacheHolderFlag cache_holder_;
const ParameterCount& arguments() { return arguments_; }
MUST_USE_RESULT MaybeObject* GetCode(PropertyType type, String* name);
// Convenience function. Calls GetCode above passing
// CONSTANT_FUNCTION type and the name of the given function.
MUST_USE_RESULT MaybeObject* GetCode(JSFunction* function);
void GenerateNameCheck(String* name, Label* miss);
void GenerateGlobalReceiverCheck(JSObject* object,
JSObject* holder,
String* name,
Label* miss);
// Generates code to load the function from the cell checking that
// it still contains the same function.
void GenerateLoadFunctionFromCell(JSGlobalPropertyCell* cell,
JSFunction* function,
Label* miss);
// Generates a jump to CallIC miss stub. Returns Failure if the jump cannot
// be generated.
MUST_USE_RESULT MaybeObject* GenerateMissBranch();
};
class ConstructStubCompiler: public StubCompiler {
public:
explicit ConstructStubCompiler() {}
MUST_USE_RESULT MaybeObject* CompileConstructStub(JSFunction* function);
private:
MaybeObject* GetCode();
};
// Holds information about possible function call optimizations.
class CallOptimization BASE_EMBEDDED {
public:
explicit CallOptimization(LookupResult* lookup);
explicit CallOptimization(JSFunction* function);
bool is_constant_call() const {
return constant_function_ != NULL;
}
JSFunction* constant_function() const {
ASSERT(constant_function_ != NULL);
return constant_function_;
}
bool is_simple_api_call() const {
return is_simple_api_call_;
}
FunctionTemplateInfo* expected_receiver_type() const {
ASSERT(is_simple_api_call_);
return expected_receiver_type_;
}
CallHandlerInfo* api_call_info() const {
ASSERT(is_simple_api_call_);
return api_call_info_;
}
// Returns the depth of the object having the expected type in the
// prototype chain between the two arguments.
int GetPrototypeDepthOfExpectedType(JSObject* object,
JSObject* holder) const;
private:
void Initialize(JSFunction* function);
// Determines whether the given function can be called using the
// fast api call builtin.
void AnalyzePossibleApiFunction(JSFunction* function);
JSFunction* constant_function_;
bool is_simple_api_call_;
FunctionTemplateInfo* expected_receiver_type_;
CallHandlerInfo* api_call_info_;
};
} } // namespace v8::internal
#endif // V8_STUB_CACHE_H_