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|
// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_COMMON_GLOBALS_H_
#define V8_COMMON_GLOBALS_H_
#include <stddef.h>
#include <stdint.h>
#include <limits>
#include <ostream>
#include "include/v8-internal.h"
#include "src/base/atomic-utils.h"
#include "src/base/build_config.h"
#include "src/base/flags.h"
#include "src/base/logging.h"
#include "src/base/macros.h"
#define V8_INFINITY std::numeric_limits<double>::infinity()
namespace v8 {
namespace base {
class Mutex;
class RecursiveMutex;
} // namespace base
namespace internal {
constexpr int KB = 1024;
constexpr int MB = KB * 1024;
constexpr int GB = MB * 1024;
// Determine whether we are running in a simulated environment.
// Setting USE_SIMULATOR explicitly from the build script will force
// the use of a simulated environment.
#if !defined(USE_SIMULATOR)
#if (V8_TARGET_ARCH_ARM64 && !V8_HOST_ARCH_ARM64)
#define USE_SIMULATOR 1
#endif
#if (V8_TARGET_ARCH_ARM && !V8_HOST_ARCH_ARM)
#define USE_SIMULATOR 1
#endif
#if (V8_TARGET_ARCH_PPC && !V8_HOST_ARCH_PPC)
#define USE_SIMULATOR 1
#endif
#if (V8_TARGET_ARCH_PPC64 && !V8_HOST_ARCH_PPC64)
#define USE_SIMULATOR 1
#endif
#if (V8_TARGET_ARCH_MIPS && !V8_HOST_ARCH_MIPS)
#define USE_SIMULATOR 1
#endif
#if (V8_TARGET_ARCH_MIPS64 && !V8_HOST_ARCH_MIPS64)
#define USE_SIMULATOR 1
#endif
#if (V8_TARGET_ARCH_S390 && !V8_HOST_ARCH_S390)
#define USE_SIMULATOR 1
#endif
#endif
// Determine whether the architecture uses an embedded constant pool
// (contiguous constant pool embedded in code object).
#if V8_TARGET_ARCH_PPC || V8_TARGET_ARCH_PPC64
#define V8_EMBEDDED_CONSTANT_POOL true
#else
#define V8_EMBEDDED_CONSTANT_POOL false
#endif
#ifdef V8_TARGET_ARCH_ARM
// Set stack limit lower for ARM than for other architectures because
// stack allocating MacroAssembler takes 120K bytes.
// See issue crbug.com/405338
#define V8_DEFAULT_STACK_SIZE_KB 864
#else
// Slightly less than 1MB, since Windows' default stack size for
// the main execution thread is 1MB for both 32 and 64-bit.
#define V8_DEFAULT_STACK_SIZE_KB 984
#endif
// Minimum stack size in KB required by compilers.
constexpr int kStackSpaceRequiredForCompilation = 40;
// In order to emit more efficient stack checks in optimized code,
// deoptimization may implicitly exceed the V8 stack limit by this many bytes.
// Stack checks in functions with `difference between optimized and unoptimized
// stack frame sizes <= slack` can simply emit the simple stack check.
constexpr int kStackLimitSlackForDeoptimizationInBytes = 256;
// Sanity-check, assuming that we aim for a real OS stack size of at least 1MB.
STATIC_ASSERT(V8_DEFAULT_STACK_SIZE_KB* KB +
kStackLimitSlackForDeoptimizationInBytes <=
MB);
// Determine whether double field unboxing feature is enabled.
#if V8_TARGET_ARCH_64_BIT && !defined(V8_COMPRESS_POINTERS)
#define V8_DOUBLE_FIELDS_UNBOXING false
#else
#define V8_DOUBLE_FIELDS_UNBOXING false
#endif
// Determine whether tagged pointers are 8 bytes (used in Torque layouts for
// choosing where to insert padding).
#if V8_TARGET_ARCH_64_BIT && !defined(V8_COMPRESS_POINTERS)
#define TAGGED_SIZE_8_BYTES true
#else
#define TAGGED_SIZE_8_BYTES false
#endif
// Some types of tracing require the SFI to store a unique ID.
#if defined(V8_TRACE_MAPS) || defined(V8_TRACE_IGNITION)
#define V8_SFI_HAS_UNIQUE_ID true
#else
#define V8_SFI_HAS_UNIQUE_ID false
#endif
#if defined(V8_OS_WIN) && defined(V8_TARGET_ARCH_X64)
#define V8_OS_WIN_X64 true
#endif
#if defined(V8_OS_WIN) && defined(V8_TARGET_ARCH_ARM64)
#define V8_OS_WIN_ARM64 true
#endif
#if defined(V8_OS_WIN_X64) || defined(V8_OS_WIN_ARM64)
#define V8_OS_WIN64 true
#endif
// Superclass for classes only using static method functions.
// The subclass of AllStatic cannot be instantiated at all.
class AllStatic {
#ifdef DEBUG
public:
AllStatic() = delete;
#endif
};
using byte = uint8_t;
// -----------------------------------------------------------------------------
// Constants
constexpr int kMaxInt = 0x7FFFFFFF;
constexpr int kMinInt = -kMaxInt - 1;
constexpr int kMaxInt8 = (1 << 7) - 1;
constexpr int kMinInt8 = -(1 << 7);
constexpr int kMaxUInt8 = (1 << 8) - 1;
constexpr int kMinUInt8 = 0;
constexpr int kMaxInt16 = (1 << 15) - 1;
constexpr int kMinInt16 = -(1 << 15);
constexpr int kMaxUInt16 = (1 << 16) - 1;
constexpr int kMinUInt16 = 0;
constexpr uint32_t kMaxUInt32 = 0xFFFFFFFFu;
constexpr int kMinUInt32 = 0;
constexpr int kUInt8Size = sizeof(uint8_t);
constexpr int kByteSize = sizeof(byte);
constexpr int kCharSize = sizeof(char);
constexpr int kShortSize = sizeof(short); // NOLINT
constexpr int kUInt16Size = sizeof(uint16_t);
constexpr int kIntSize = sizeof(int);
constexpr int kInt32Size = sizeof(int32_t);
constexpr int kInt64Size = sizeof(int64_t);
constexpr int kUInt32Size = sizeof(uint32_t);
constexpr int kSizetSize = sizeof(size_t);
constexpr int kFloatSize = sizeof(float);
constexpr int kDoubleSize = sizeof(double);
constexpr int kIntptrSize = sizeof(intptr_t);
constexpr int kUIntptrSize = sizeof(uintptr_t);
constexpr int kSystemPointerSize = sizeof(void*);
constexpr int kSystemPointerHexDigits = kSystemPointerSize == 4 ? 8 : 12;
constexpr int kPCOnStackSize = kSystemPointerSize;
constexpr int kFPOnStackSize = kSystemPointerSize;
#if V8_TARGET_ARCH_X64 || V8_TARGET_ARCH_IA32
constexpr int kElidedFrameSlots = kPCOnStackSize / kSystemPointerSize;
#else
constexpr int kElidedFrameSlots = 0;
#endif
constexpr int kDoubleSizeLog2 = 3;
constexpr size_t kMaxWasmCodeMB = 1024;
constexpr size_t kMaxWasmCodeMemory = kMaxWasmCodeMB * MB;
#if V8_TARGET_ARCH_ARM64
// ARM64 only supports direct calls within a 128 MB range.
constexpr size_t kMaxWasmCodeSpaceSize = 128 * MB;
#else
constexpr size_t kMaxWasmCodeSpaceSize = kMaxWasmCodeMemory;
#endif
#if V8_HOST_ARCH_64_BIT
constexpr int kSystemPointerSizeLog2 = 3;
constexpr intptr_t kIntptrSignBit =
static_cast<intptr_t>(uintptr_t{0x8000000000000000});
constexpr bool kPlatformRequiresCodeRange = true;
#if (V8_HOST_ARCH_PPC || V8_HOST_ARCH_PPC64) && \
(V8_TARGET_ARCH_PPC || V8_TARGET_ARCH_PPC64) && V8_OS_LINUX
constexpr size_t kMaximalCodeRangeSize = 512 * MB;
constexpr size_t kMinExpectedOSPageSize = 64 * KB; // OS page on PPC Linux
#elif V8_TARGET_ARCH_ARM64
constexpr size_t kMaximalCodeRangeSize = 128 * MB;
constexpr size_t kMinExpectedOSPageSize = 4 * KB; // OS page.
#else
constexpr size_t kMaximalCodeRangeSize = 128 * MB;
constexpr size_t kMinExpectedOSPageSize = 4 * KB; // OS page.
#endif
#if V8_OS_WIN
constexpr size_t kMinimumCodeRangeSize = 4 * MB;
constexpr size_t kReservedCodeRangePages = 1;
#else
constexpr size_t kMinimumCodeRangeSize = 3 * MB;
constexpr size_t kReservedCodeRangePages = 0;
#endif
#else
constexpr int kSystemPointerSizeLog2 = 2;
constexpr intptr_t kIntptrSignBit = 0x80000000;
#if (V8_HOST_ARCH_PPC || V8_HOST_ARCH_PPC64) && \
(V8_TARGET_ARCH_PPC || V8_TARGET_ARCH_PPC64) && V8_OS_LINUX
constexpr bool kPlatformRequiresCodeRange = false;
constexpr size_t kMaximalCodeRangeSize = 0 * MB;
constexpr size_t kMinimumCodeRangeSize = 0 * MB;
constexpr size_t kMinExpectedOSPageSize = 64 * KB; // OS page on PPC Linux
#elif V8_TARGET_ARCH_MIPS
constexpr bool kPlatformRequiresCodeRange = false;
constexpr size_t kMaximalCodeRangeSize = 2048LL * MB;
constexpr size_t kMinimumCodeRangeSize = 0 * MB;
constexpr size_t kMinExpectedOSPageSize = 4 * KB; // OS page.
#else
constexpr bool kPlatformRequiresCodeRange = false;
constexpr size_t kMaximalCodeRangeSize = 0 * MB;
constexpr size_t kMinimumCodeRangeSize = 0 * MB;
constexpr size_t kMinExpectedOSPageSize = 4 * KB; // OS page.
#endif
constexpr size_t kReservedCodeRangePages = 0;
#endif
STATIC_ASSERT(kSystemPointerSize == (1 << kSystemPointerSizeLog2));
#ifdef V8_COMPRESS_POINTERS
static_assert(
kSystemPointerSize == kInt64Size,
"Pointer compression can be enabled only for 64-bit architectures");
constexpr int kTaggedSize = kInt32Size;
constexpr int kTaggedSizeLog2 = 2;
// These types define raw and atomic storage types for tagged values stored
// on V8 heap.
using Tagged_t = uint32_t;
using AtomicTagged_t = base::Atomic32;
#else
constexpr int kTaggedSize = kSystemPointerSize;
constexpr int kTaggedSizeLog2 = kSystemPointerSizeLog2;
// These types define raw and atomic storage types for tagged values stored
// on V8 heap.
using Tagged_t = Address;
using AtomicTagged_t = base::AtomicWord;
#endif // V8_COMPRESS_POINTERS
STATIC_ASSERT(kTaggedSize == (1 << kTaggedSizeLog2));
STATIC_ASSERT((kTaggedSize == 8) == TAGGED_SIZE_8_BYTES);
using AsAtomicTagged = base::AsAtomicPointerImpl<AtomicTagged_t>;
STATIC_ASSERT(sizeof(Tagged_t) == kTaggedSize);
STATIC_ASSERT(sizeof(AtomicTagged_t) == kTaggedSize);
STATIC_ASSERT(kTaggedSize == kApiTaggedSize);
// TODO(ishell): use kTaggedSize or kSystemPointerSize instead.
#ifndef V8_COMPRESS_POINTERS
constexpr int kPointerSize = kSystemPointerSize;
constexpr int kPointerSizeLog2 = kSystemPointerSizeLog2;
STATIC_ASSERT(kPointerSize == (1 << kPointerSizeLog2));
#endif
constexpr int kEmbedderDataSlotSize = kSystemPointerSize;
constexpr int kEmbedderDataSlotSizeInTaggedSlots =
kEmbedderDataSlotSize / kTaggedSize;
STATIC_ASSERT(kEmbedderDataSlotSize >= kSystemPointerSize);
constexpr int kExternalAllocationSoftLimit =
internal::Internals::kExternalAllocationSoftLimit;
// Maximum object size that gets allocated into regular pages. Objects larger
// than that size are allocated in large object space and are never moved in
// memory. This also applies to new space allocation, since objects are never
// migrated from new space to large object space. Takes double alignment into
// account.
//
// Current value: half of the page size.
constexpr int kMaxRegularHeapObjectSize = (1 << (kPageSizeBits - 1));
constexpr int kBitsPerByte = 8;
constexpr int kBitsPerByteLog2 = 3;
constexpr int kBitsPerSystemPointer = kSystemPointerSize * kBitsPerByte;
constexpr int kBitsPerSystemPointerLog2 =
kSystemPointerSizeLog2 + kBitsPerByteLog2;
constexpr int kBitsPerInt = kIntSize * kBitsPerByte;
// IEEE 754 single precision floating point number bit layout.
constexpr uint32_t kBinary32SignMask = 0x80000000u;
constexpr uint32_t kBinary32ExponentMask = 0x7f800000u;
constexpr uint32_t kBinary32MantissaMask = 0x007fffffu;
constexpr int kBinary32ExponentBias = 127;
constexpr int kBinary32MaxExponent = 0xFE;
constexpr int kBinary32MinExponent = 0x01;
constexpr int kBinary32MantissaBits = 23;
constexpr int kBinary32ExponentShift = 23;
// Quiet NaNs have bits 51 to 62 set, possibly the sign bit, and no
// other bits set.
constexpr uint64_t kQuietNaNMask = static_cast<uint64_t>(0xfff) << 51;
// Latin1/UTF-16 constants
// Code-point values in Unicode 4.0 are 21 bits wide.
// Code units in UTF-16 are 16 bits wide.
using uc16 = uint16_t;
using uc32 = int32_t;
constexpr int kOneByteSize = kCharSize;
constexpr int kUC16Size = sizeof(uc16); // NOLINT
// 128 bit SIMD value size.
constexpr int kSimd128Size = 16;
// FUNCTION_ADDR(f) gets the address of a C function f.
#define FUNCTION_ADDR(f) (reinterpret_cast<v8::internal::Address>(f))
// FUNCTION_CAST<F>(addr) casts an address into a function
// of type F. Used to invoke generated code from within C.
template <typename F>
F FUNCTION_CAST(byte* addr) {
return reinterpret_cast<F>(reinterpret_cast<Address>(addr));
}
template <typename F>
F FUNCTION_CAST(Address addr) {
return reinterpret_cast<F>(addr);
}
// Determine whether the architecture uses function descriptors
// which provide a level of indirection between the function pointer
// and the function entrypoint.
#if (V8_HOST_ARCH_PPC || V8_HOST_ARCH_PPC64) && \
(V8_OS_AIX || (V8_TARGET_ARCH_PPC64 && V8_TARGET_BIG_ENDIAN && \
(!defined(_CALL_ELF) || _CALL_ELF == 1)))
#define USES_FUNCTION_DESCRIPTORS 1
#define FUNCTION_ENTRYPOINT_ADDRESS(f) \
(reinterpret_cast<v8::internal::Address*>( \
&(reinterpret_cast<intptr_t*>(f)[0])))
#else
#define USES_FUNCTION_DESCRIPTORS 0
#endif
// -----------------------------------------------------------------------------
// Declarations for use in both the preparser and the rest of V8.
// The Strict Mode (ECMA-262 5th edition, 4.2.2).
enum class LanguageMode : bool { kSloppy, kStrict };
static const size_t LanguageModeSize = 2;
inline size_t hash_value(LanguageMode mode) {
return static_cast<size_t>(mode);
}
inline const char* LanguageMode2String(LanguageMode mode) {
switch (mode) {
case LanguageMode::kSloppy:
return "sloppy";
case LanguageMode::kStrict:
return "strict";
}
UNREACHABLE();
}
inline std::ostream& operator<<(std::ostream& os, LanguageMode mode) {
return os << LanguageMode2String(mode);
}
inline bool is_sloppy(LanguageMode language_mode) {
return language_mode == LanguageMode::kSloppy;
}
inline bool is_strict(LanguageMode language_mode) {
return language_mode != LanguageMode::kSloppy;
}
inline bool is_valid_language_mode(int language_mode) {
return language_mode == static_cast<int>(LanguageMode::kSloppy) ||
language_mode == static_cast<int>(LanguageMode::kStrict);
}
inline LanguageMode construct_language_mode(bool strict_bit) {
return static_cast<LanguageMode>(strict_bit);
}
// Return kStrict if either of the language modes is kStrict, or kSloppy
// otherwise.
inline LanguageMode stricter_language_mode(LanguageMode mode1,
LanguageMode mode2) {
STATIC_ASSERT(LanguageModeSize == 2);
return static_cast<LanguageMode>(static_cast<int>(mode1) |
static_cast<int>(mode2));
}
// A non-keyed store is of the form a.x = foo or a["x"] = foo whereas
// a keyed store is of the form a[expression] = foo.
enum class StoreOrigin { kMaybeKeyed, kNamed };
enum TypeofMode : int { INSIDE_TYPEOF, NOT_INSIDE_TYPEOF };
// Enums used by CEntry.
enum SaveFPRegsMode { kDontSaveFPRegs, kSaveFPRegs };
enum ArgvMode { kArgvOnStack, kArgvInRegister };
// This constant is used as an undefined value when passing source positions.
constexpr int kNoSourcePosition = -1;
// This constant is used to signal the function entry implicit stack check
// bytecode offset.
constexpr int kFunctionEntryBytecodeOffset = -1;
// This constant is used to indicate missing deoptimization information.
constexpr int kNoDeoptimizationId = -1;
// Deoptimize bailout kind:
// - Eager: a check failed in the optimized code and deoptimization happens
// immediately.
// - Lazy: the code has been marked as dependent on some assumption which
// is checked elsewhere and can trigger deoptimization the next time the
// code is executed.
// - Soft: similar to lazy deoptimization, but does not contribute to the
// total deopt count which can lead to disabling optimization for a function.
enum class DeoptimizeKind : uint8_t {
kEager,
kSoft,
kLazy,
kLastDeoptimizeKind = kLazy
};
inline size_t hash_value(DeoptimizeKind kind) {
return static_cast<size_t>(kind);
}
inline std::ostream& operator<<(std::ostream& os, DeoptimizeKind kind) {
switch (kind) {
case DeoptimizeKind::kEager:
return os << "Eager";
case DeoptimizeKind::kSoft:
return os << "Soft";
case DeoptimizeKind::kLazy:
return os << "Lazy";
}
UNREACHABLE();
}
enum class IsolateAllocationMode {
// Allocate Isolate in C++ heap using default new/delete operators.
kInCppHeap,
// Allocate Isolate in a committed region inside V8 heap reservation.
kInV8Heap,
#ifdef V8_COMPRESS_POINTERS
kDefault = kInV8Heap,
#else
kDefault = kInCppHeap,
#endif
};
// Indicates whether the lookup is related to sloppy-mode block-scoped
// function hoisting, and is a synthetic assignment for that.
enum class LookupHoistingMode { kNormal, kLegacySloppy };
inline std::ostream& operator<<(std::ostream& os,
const LookupHoistingMode& mode) {
switch (mode) {
case LookupHoistingMode::kNormal:
return os << "normal hoisting";
case LookupHoistingMode::kLegacySloppy:
return os << "legacy sloppy hoisting";
}
UNREACHABLE();
}
static_assert(kSmiValueSize <= 32, "Unsupported Smi tagging scheme");
// Smi sign bit position must be 32-bit aligned so we can use sign extension
// instructions on 64-bit architectures without additional shifts.
static_assert((kSmiValueSize + kSmiShiftSize + kSmiTagSize) % 32 == 0,
"Unsupported Smi tagging scheme");
constexpr bool kIsSmiValueInUpper32Bits =
(kSmiValueSize + kSmiShiftSize + kSmiTagSize) == 64;
constexpr bool kIsSmiValueInLower32Bits =
(kSmiValueSize + kSmiShiftSize + kSmiTagSize) == 32;
static_assert(!SmiValuesAre32Bits() == SmiValuesAre31Bits(),
"Unsupported Smi tagging scheme");
static_assert(SmiValuesAre32Bits() == kIsSmiValueInUpper32Bits,
"Unsupported Smi tagging scheme");
static_assert(SmiValuesAre31Bits() == kIsSmiValueInLower32Bits,
"Unsupported Smi tagging scheme");
// Mask for the sign bit in a smi.
constexpr intptr_t kSmiSignMask = static_cast<intptr_t>(
uintptr_t{1} << (kSmiValueSize + kSmiShiftSize + kSmiTagSize - 1));
// Desired alignment for tagged pointers.
constexpr int kObjectAlignmentBits = kTaggedSizeLog2;
constexpr intptr_t kObjectAlignment = 1 << kObjectAlignmentBits;
constexpr intptr_t kObjectAlignmentMask = kObjectAlignment - 1;
// Desired alignment for system pointers.
constexpr intptr_t kPointerAlignment = (1 << kSystemPointerSizeLog2);
constexpr intptr_t kPointerAlignmentMask = kPointerAlignment - 1;
// Desired alignment for double values.
constexpr intptr_t kDoubleAlignment = 8;
constexpr intptr_t kDoubleAlignmentMask = kDoubleAlignment - 1;
// Desired alignment for generated code is 32 bytes (to improve cache line
// utilization).
constexpr int kCodeAlignmentBits = 5;
constexpr intptr_t kCodeAlignment = 1 << kCodeAlignmentBits;
constexpr intptr_t kCodeAlignmentMask = kCodeAlignment - 1;
const Address kWeakHeapObjectMask = 1 << 1;
// The lower 32 bits of the cleared weak reference value is always equal to
// the |kClearedWeakHeapObjectLower32| constant but on 64-bit architectures
// the value of the upper 32 bits part may be
// 1) zero when pointer compression is disabled,
// 2) upper 32 bits of the isolate root value when pointer compression is
// enabled.
// This is necessary to make pointer decompression computation also suitable
// for cleared weak reference.
// Note, that real heap objects can't have lower 32 bits equal to 3 because
// this offset belongs to page header. So, in either case it's enough to
// compare only the lower 32 bits of a MaybeObject value in order to figure
// out if it's a cleared reference or not.
const uint32_t kClearedWeakHeapObjectLower32 = 3;
// Zap-value: The value used for zapping dead objects.
// Should be a recognizable hex value tagged as a failure.
#ifdef V8_HOST_ARCH_64_BIT
constexpr uint64_t kClearedFreeMemoryValue = 0;
constexpr uint64_t kZapValue = uint64_t{0xdeadbeedbeadbeef};
constexpr uint64_t kHandleZapValue = uint64_t{0x1baddead0baddeaf};
constexpr uint64_t kGlobalHandleZapValue = uint64_t{0x1baffed00baffedf};
constexpr uint64_t kFromSpaceZapValue = uint64_t{0x1beefdad0beefdaf};
constexpr uint64_t kDebugZapValue = uint64_t{0xbadbaddbbadbaddb};
constexpr uint64_t kSlotsZapValue = uint64_t{0xbeefdeadbeefdeef};
constexpr uint64_t kFreeListZapValue = 0xfeed1eaffeed1eaf;
#else
constexpr uint32_t kClearedFreeMemoryValue = 0;
constexpr uint32_t kZapValue = 0xdeadbeef;
constexpr uint32_t kHandleZapValue = 0xbaddeaf;
constexpr uint32_t kGlobalHandleZapValue = 0xbaffedf;
constexpr uint32_t kFromSpaceZapValue = 0xbeefdaf;
constexpr uint32_t kSlotsZapValue = 0xbeefdeef;
constexpr uint32_t kDebugZapValue = 0xbadbaddb;
constexpr uint32_t kFreeListZapValue = 0xfeed1eaf;
#endif
constexpr int kCodeZapValue = 0xbadc0de;
constexpr uint32_t kPhantomReferenceZap = 0xca11bac;
// Page constants.
static const intptr_t kPageAlignmentMask = (intptr_t{1} << kPageSizeBits) - 1;
// On Intel architecture, cache line size is 64 bytes.
// On ARM it may be less (32 bytes), but as far this constant is
// used for aligning data, it doesn't hurt to align on a greater value.
#define PROCESSOR_CACHE_LINE_SIZE 64
// Constants relevant to double precision floating point numbers.
// If looking only at the top 32 bits, the QNaN mask is bits 19 to 30.
constexpr uint32_t kQuietNaNHighBitsMask = 0xfff << (51 - 32);
enum class HeapObjectReferenceType {
WEAK,
STRONG,
};
enum class ArgumentsType {
kRuntime,
kJS,
};
// -----------------------------------------------------------------------------
// Forward declarations for frequently used classes
class AccessorInfo;
template <ArgumentsType>
class Arguments;
using RuntimeArguments = Arguments<ArgumentsType::kRuntime>;
using JavaScriptArguments = Arguments<ArgumentsType::kJS>;
class Assembler;
class ClassScope;
class Code;
class CodeSpace;
class Context;
class DeclarationScope;
class Debug;
class DebugInfo;
class Descriptor;
class DescriptorArray;
class TransitionArray;
class ExternalReference;
class FeedbackVector;
class FixedArray;
class Foreign;
class FreeStoreAllocationPolicy;
class FunctionTemplateInfo;
class GlobalDictionary;
template <typename T>
class Handle;
class Heap;
class HeapObject;
class HeapObjectReference;
class IC;
class InterceptorInfo;
class Isolate;
class JSReceiver;
class JSArray;
class JSFunction;
class JSObject;
class MacroAssembler;
class Map;
class MapSpace;
class MarkCompactCollector;
template <typename T>
class MaybeHandle;
class MaybeObject;
class MemoryChunk;
class MessageLocation;
class ModuleScope;
class Name;
class NameDictionary;
class NativeContext;
class NewSpace;
class NewLargeObjectSpace;
class NumberDictionary;
class Object;
class OldLargeObjectSpace;
template <HeapObjectReferenceType kRefType, typename StorageType>
class TaggedImpl;
class StrongTaggedValue;
class TaggedValue;
class CompressedObjectSlot;
class CompressedMaybeObjectSlot;
class CompressedMapWordSlot;
class CompressedHeapObjectSlot;
class FullObjectSlot;
class FullMaybeObjectSlot;
class FullHeapObjectSlot;
class OldSpace;
class ReadOnlySpace;
class RelocInfo;
class Scope;
class ScopeInfo;
class Script;
class SimpleNumberDictionary;
class Smi;
template <typename Config, class Allocator = FreeStoreAllocationPolicy>
class SplayTree;
class String;
class StringStream;
class Struct;
class Symbol;
class Variable;
enum class SlotLocation { kOnHeap, kOffHeap };
template <SlotLocation slot_location>
struct SlotTraits;
// Off-heap slots are always full-pointer slots.
template <>
struct SlotTraits<SlotLocation::kOffHeap> {
using TObjectSlot = FullObjectSlot;
using TMaybeObjectSlot = FullMaybeObjectSlot;
using THeapObjectSlot = FullHeapObjectSlot;
};
// On-heap slots are either full-pointer slots or compressed slots depending
// on whether the pointer compression is enabled or not.
template <>
struct SlotTraits<SlotLocation::kOnHeap> {
#ifdef V8_COMPRESS_POINTERS
using TObjectSlot = CompressedObjectSlot;
using TMaybeObjectSlot = CompressedMaybeObjectSlot;
using THeapObjectSlot = CompressedHeapObjectSlot;
#else
using TObjectSlot = FullObjectSlot;
using TMaybeObjectSlot = FullMaybeObjectSlot;
using THeapObjectSlot = FullHeapObjectSlot;
#endif
};
// An ObjectSlot instance describes a kTaggedSize-sized on-heap field ("slot")
// holding Object value (smi or strong heap object).
using ObjectSlot = SlotTraits<SlotLocation::kOnHeap>::TObjectSlot;
// A MaybeObjectSlot instance describes a kTaggedSize-sized on-heap field
// ("slot") holding MaybeObject (smi or weak heap object or strong heap object).
using MaybeObjectSlot = SlotTraits<SlotLocation::kOnHeap>::TMaybeObjectSlot;
// A HeapObjectSlot instance describes a kTaggedSize-sized field ("slot")
// holding a weak or strong pointer to a heap object (think:
// HeapObjectReference).
using HeapObjectSlot = SlotTraits<SlotLocation::kOnHeap>::THeapObjectSlot;
using WeakSlotCallback = bool (*)(FullObjectSlot pointer);
using WeakSlotCallbackWithHeap = bool (*)(Heap* heap, FullObjectSlot pointer);
// -----------------------------------------------------------------------------
// Miscellaneous
// NOTE: SpaceIterator depends on AllocationSpace enumeration values being
// consecutive.
enum AllocationSpace {
RO_SPACE, // Immortal, immovable and immutable objects,
NEW_SPACE, // Young generation semispaces for regular objects collected with
// Scavenger.
OLD_SPACE, // Old generation regular object space.
CODE_SPACE, // Old generation code object space, marked executable.
MAP_SPACE, // Old generation map object space, non-movable.
LO_SPACE, // Old generation large object space.
CODE_LO_SPACE, // Old generation large code object space.
NEW_LO_SPACE, // Young generation large object space.
FIRST_SPACE = RO_SPACE,
LAST_SPACE = NEW_LO_SPACE,
FIRST_MUTABLE_SPACE = NEW_SPACE,
LAST_MUTABLE_SPACE = NEW_LO_SPACE,
FIRST_GROWABLE_PAGED_SPACE = OLD_SPACE,
LAST_GROWABLE_PAGED_SPACE = MAP_SPACE
};
constexpr int kSpaceTagSize = 4;
STATIC_ASSERT(FIRST_SPACE == 0);
enum class AllocationType : uint8_t {
kYoung, // Regular object allocated in NEW_SPACE or NEW_LO_SPACE
kOld, // Regular object allocated in OLD_SPACE or LO_SPACE
kCode, // Code object allocated in CODE_SPACE or CODE_LO_SPACE
kMap, // Map object allocated in MAP_SPACE
kReadOnly // Object allocated in RO_SPACE
};
inline size_t hash_value(AllocationType kind) {
return static_cast<uint8_t>(kind);
}
inline std::ostream& operator<<(std::ostream& os, AllocationType kind) {
switch (kind) {
case AllocationType::kYoung:
return os << "Young";
case AllocationType::kOld:
return os << "Old";
case AllocationType::kCode:
return os << "Code";
case AllocationType::kMap:
return os << "Map";
case AllocationType::kReadOnly:
return os << "ReadOnly";
}
UNREACHABLE();
}
// TODO(ishell): review and rename kWordAligned to kTaggedAligned.
enum AllocationAlignment {
kWordAligned,
kDoubleAligned,
kDoubleUnaligned,
kCodeAligned
};
enum class AccessMode { ATOMIC, NON_ATOMIC };
enum class AllowLargeObjects { kFalse, kTrue };
enum MinimumCapacity {
USE_DEFAULT_MINIMUM_CAPACITY,
USE_CUSTOM_MINIMUM_CAPACITY
};
enum GarbageCollector { SCAVENGER, MARK_COMPACTOR, MINOR_MARK_COMPACTOR };
enum class LocalSpaceKind {
kNone,
kOffThreadSpace,
kCompactionSpaceForScavenge,
kCompactionSpaceForMarkCompact,
kCompactionSpaceForMinorMarkCompact,
kFirstCompactionSpace = kCompactionSpaceForScavenge,
kLastCompactionSpace = kCompactionSpaceForMinorMarkCompact,
};
enum Executability { NOT_EXECUTABLE, EXECUTABLE };
enum VisitMode {
VISIT_ALL,
VISIT_ALL_IN_MINOR_MC_MARK,
VISIT_ALL_IN_MINOR_MC_UPDATE,
VISIT_ALL_IN_SCAVENGE,
VISIT_ALL_IN_SWEEP_NEWSPACE,
VISIT_ONLY_STRONG,
VISIT_ONLY_STRONG_IGNORE_STACK,
VISIT_FOR_SERIALIZATION,
};
enum class BytecodeFlushMode {
kDoNotFlushBytecode,
kFlushBytecode,
kStressFlushBytecode,
};
// Indicates whether a script should be parsed and compiled in REPL mode.
enum class REPLMode {
kYes,
kNo,
};
inline REPLMode construct_repl_mode(bool is_repl_mode) {
return is_repl_mode ? REPLMode::kYes : REPLMode::kNo;
}
// Flag indicating whether code is built into the VM (one of the natives files).
enum NativesFlag { NOT_NATIVES_CODE, EXTENSION_CODE, INSPECTOR_CODE };
// ParseRestriction is used to restrict the set of valid statements in a
// unit of compilation. Restriction violations cause a syntax error.
enum ParseRestriction {
NO_PARSE_RESTRICTION, // All expressions are allowed.
ONLY_SINGLE_FUNCTION_LITERAL // Only a single FunctionLiteral expression.
};
// State for inline cache call sites. Aliased as IC::State.
enum InlineCacheState {
// No feedback will be collected.
NO_FEEDBACK,
// Has never been executed.
UNINITIALIZED,
// Has been executed and only one receiver type has been seen.
MONOMORPHIC,
// Check failed due to prototype (or map deprecation).
RECOMPUTE_HANDLER,
// Multiple receiver types have been seen.
POLYMORPHIC,
// Many receiver types have been seen.
MEGAMORPHIC,
// A generic handler is installed and no extra typefeedback is recorded.
GENERIC,
};
// Printing support.
inline const char* InlineCacheState2String(InlineCacheState state) {
switch (state) {
case NO_FEEDBACK:
return "NOFEEDBACK";
case UNINITIALIZED:
return "UNINITIALIZED";
case MONOMORPHIC:
return "MONOMORPHIC";
case RECOMPUTE_HANDLER:
return "RECOMPUTE_HANDLER";
case POLYMORPHIC:
return "POLYMORPHIC";
case MEGAMORPHIC:
return "MEGAMORPHIC";
case GENERIC:
return "GENERIC";
}
UNREACHABLE();
}
enum WhereToStart { kStartAtReceiver, kStartAtPrototype };
enum ResultSentinel { kNotFound = -1, kUnsupported = -2 };
enum ShouldThrow {
kThrowOnError = Internals::kThrowOnError,
kDontThrow = Internals::kDontThrow
};
// The Store Buffer (GC).
enum StoreBufferEvent {
kStoreBufferFullEvent,
kStoreBufferStartScanningPagesEvent,
kStoreBufferScanningPageEvent
};
using StoreBufferCallback = void (*)(Heap* heap, MemoryChunk* page,
StoreBufferEvent event);
// Union used for customized checking of the IEEE double types
// inlined within v8 runtime, rather than going to the underlying
// platform headers and libraries
union IeeeDoubleLittleEndianArchType {
double d;
struct {
unsigned int man_low : 32;
unsigned int man_high : 20;
unsigned int exp : 11;
unsigned int sign : 1;
} bits;
};
union IeeeDoubleBigEndianArchType {
double d;
struct {
unsigned int sign : 1;
unsigned int exp : 11;
unsigned int man_high : 20;
unsigned int man_low : 32;
} bits;
};
#if V8_TARGET_LITTLE_ENDIAN
using IeeeDoubleArchType = IeeeDoubleLittleEndianArchType;
constexpr int kIeeeDoubleMantissaWordOffset = 0;
constexpr int kIeeeDoubleExponentWordOffset = 4;
#else
using IeeeDoubleArchType = IeeeDoubleBigEndianArchType;
constexpr int kIeeeDoubleMantissaWordOffset = 4;
constexpr int kIeeeDoubleExponentWordOffset = 0;
#endif
// -----------------------------------------------------------------------------
// Macros
// Testers for test.
#define HAS_SMI_TAG(value) \
((static_cast<i::Tagged_t>(value) & ::i::kSmiTagMask) == ::i::kSmiTag)
#define HAS_STRONG_HEAP_OBJECT_TAG(value) \
(((static_cast<i::Tagged_t>(value) & ::i::kHeapObjectTagMask) == \
::i::kHeapObjectTag))
#define HAS_WEAK_HEAP_OBJECT_TAG(value) \
(((static_cast<i::Tagged_t>(value) & ::i::kHeapObjectTagMask) == \
::i::kWeakHeapObjectTag))
// OBJECT_POINTER_ALIGN returns the value aligned as a HeapObject pointer
#define OBJECT_POINTER_ALIGN(value) \
(((value) + ::i::kObjectAlignmentMask) & ~::i::kObjectAlignmentMask)
// OBJECT_POINTER_PADDING returns the padding size required to align value
// as a HeapObject pointer
#define OBJECT_POINTER_PADDING(value) (OBJECT_POINTER_ALIGN(value) - (value))
// POINTER_SIZE_ALIGN returns the value aligned as a system pointer.
#define POINTER_SIZE_ALIGN(value) \
(((value) + ::i::kPointerAlignmentMask) & ~::i::kPointerAlignmentMask)
// POINTER_SIZE_PADDING returns the padding size required to align value
// as a system pointer.
#define POINTER_SIZE_PADDING(value) (POINTER_SIZE_ALIGN(value) - (value))
// CODE_POINTER_ALIGN returns the value aligned as a generated code segment.
#define CODE_POINTER_ALIGN(value) \
(((value) + ::i::kCodeAlignmentMask) & ~::i::kCodeAlignmentMask)
// CODE_POINTER_PADDING returns the padding size required to align value
// as a generated code segment.
#define CODE_POINTER_PADDING(value) (CODE_POINTER_ALIGN(value) - (value))
// DOUBLE_POINTER_ALIGN returns the value algined for double pointers.
#define DOUBLE_POINTER_ALIGN(value) \
(((value) + ::i::kDoubleAlignmentMask) & ~::i::kDoubleAlignmentMask)
// Defines hints about receiver values based on structural knowledge.
enum class ConvertReceiverMode : unsigned {
kNullOrUndefined, // Guaranteed to be null or undefined.
kNotNullOrUndefined, // Guaranteed to never be null or undefined.
kAny // No specific knowledge about receiver.
};
inline size_t hash_value(ConvertReceiverMode mode) {
return bit_cast<unsigned>(mode);
}
inline std::ostream& operator<<(std::ostream& os, ConvertReceiverMode mode) {
switch (mode) {
case ConvertReceiverMode::kNullOrUndefined:
return os << "NULL_OR_UNDEFINED";
case ConvertReceiverMode::kNotNullOrUndefined:
return os << "NOT_NULL_OR_UNDEFINED";
case ConvertReceiverMode::kAny:
return os << "ANY";
}
UNREACHABLE();
}
// Valid hints for the abstract operation OrdinaryToPrimitive,
// implemented according to ES6, section 7.1.1.
enum class OrdinaryToPrimitiveHint { kNumber, kString };
// Valid hints for the abstract operation ToPrimitive,
// implemented according to ES6, section 7.1.1.
enum class ToPrimitiveHint { kDefault, kNumber, kString };
// Defines specifics about arguments object or rest parameter creation.
enum class CreateArgumentsType : uint8_t {
kMappedArguments,
kUnmappedArguments,
kRestParameter
};
inline size_t hash_value(CreateArgumentsType type) {
return bit_cast<uint8_t>(type);
}
inline std::ostream& operator<<(std::ostream& os, CreateArgumentsType type) {
switch (type) {
case CreateArgumentsType::kMappedArguments:
return os << "MAPPED_ARGUMENTS";
case CreateArgumentsType::kUnmappedArguments:
return os << "UNMAPPED_ARGUMENTS";
case CreateArgumentsType::kRestParameter:
return os << "REST_PARAMETER";
}
UNREACHABLE();
}
enum ScopeType : uint8_t {
CLASS_SCOPE, // The scope introduced by a class.
EVAL_SCOPE, // The top-level scope for an eval source.
FUNCTION_SCOPE, // The top-level scope for a function.
MODULE_SCOPE, // The scope introduced by a module literal
SCRIPT_SCOPE, // The top-level scope for a script or a top-level eval.
CATCH_SCOPE, // The scope introduced by catch.
BLOCK_SCOPE, // The scope introduced by a new block.
WITH_SCOPE // The scope introduced by with.
};
inline std::ostream& operator<<(std::ostream& os, ScopeType type) {
switch (type) {
case ScopeType::EVAL_SCOPE:
return os << "EVAL_SCOPE";
case ScopeType::FUNCTION_SCOPE:
return os << "FUNCTION_SCOPE";
case ScopeType::MODULE_SCOPE:
return os << "MODULE_SCOPE";
case ScopeType::SCRIPT_SCOPE:
return os << "SCRIPT_SCOPE";
case ScopeType::CATCH_SCOPE:
return os << "CATCH_SCOPE";
case ScopeType::BLOCK_SCOPE:
return os << "BLOCK_SCOPE";
case ScopeType::CLASS_SCOPE:
return os << "CLASS_SCOPE";
case ScopeType::WITH_SCOPE:
return os << "WITH_SCOPE";
}
UNREACHABLE();
}
// AllocationSiteMode controls whether allocations are tracked by an allocation
// site.
enum AllocationSiteMode {
DONT_TRACK_ALLOCATION_SITE,
TRACK_ALLOCATION_SITE,
LAST_ALLOCATION_SITE_MODE = TRACK_ALLOCATION_SITE
};
enum class AllocationSiteUpdateMode { kUpdate, kCheckOnly };
// The mips architecture prior to revision 5 has inverted encoding for sNaN.
#if (V8_TARGET_ARCH_MIPS && !defined(_MIPS_ARCH_MIPS32R6) && \
(!defined(USE_SIMULATOR) || !defined(_MIPS_TARGET_SIMULATOR))) || \
(V8_TARGET_ARCH_MIPS64 && !defined(_MIPS_ARCH_MIPS64R6) && \
(!defined(USE_SIMULATOR) || !defined(_MIPS_TARGET_SIMULATOR)))
constexpr uint32_t kHoleNanUpper32 = 0xFFFF7FFF;
constexpr uint32_t kHoleNanLower32 = 0xFFFF7FFF;
#else
constexpr uint32_t kHoleNanUpper32 = 0xFFF7FFFF;
constexpr uint32_t kHoleNanLower32 = 0xFFF7FFFF;
#endif
constexpr uint64_t kHoleNanInt64 =
(static_cast<uint64_t>(kHoleNanUpper32) << 32) | kHoleNanLower32;
// ES6 section 20.1.2.6 Number.MAX_SAFE_INTEGER
constexpr uint64_t kMaxSafeIntegerUint64 = 9007199254740991; // 2^53-1
constexpr double kMaxSafeInteger = static_cast<double>(kMaxSafeIntegerUint64);
constexpr double kMaxUInt32Double = double{kMaxUInt32};
// The order of this enum has to be kept in sync with the predicates below.
enum class VariableMode : uint8_t {
// User declared variables:
kLet, // declared via 'let' declarations (first lexical)
kConst, // declared via 'const' declarations (last lexical)
kVar, // declared via 'var', and 'function' declarations
// Variables introduced by the compiler:
kTemporary, // temporary variables (not user-visible), stack-allocated
// unless the scope as a whole has forced context allocation
kDynamic, // always require dynamic lookup (we don't know
// the declaration)
kDynamicGlobal, // requires dynamic lookup, but we know that the
// variable is global unless it has been shadowed
// by an eval-introduced variable
kDynamicLocal, // requires dynamic lookup, but we know that the
// variable is local and where it is unless it
// has been shadowed by an eval-introduced
// variable
// Variables for private methods or accessors whose access require
// brand check. Declared only in class scopes by the compiler
// and allocated only in class contexts:
kPrivateMethod, // Does not coexist with any other variable with the same
// name in the same scope.
kPrivateSetterOnly, // Incompatible with variables with the same name but
// any mode other than kPrivateGetterOnly. Transition to
// kPrivateGetterAndSetter if a later declaration for the
// same name with kPrivateGetterOnly is made.
kPrivateGetterOnly, // Incompatible with variables with the same name but
// any mode other than kPrivateSetterOnly. Transition to
// kPrivateGetterAndSetter if a later declaration for the
// same name with kPrivateSetterOnly is made.
kPrivateGetterAndSetter, // Does not coexist with any other variable with the
// same name in the same scope.
kLastLexicalVariableMode = kConst,
};
// Printing support
#ifdef DEBUG
inline const char* VariableMode2String(VariableMode mode) {
switch (mode) {
case VariableMode::kVar:
return "VAR";
case VariableMode::kLet:
return "LET";
case VariableMode::kPrivateGetterOnly:
return "PRIVATE_GETTER_ONLY";
case VariableMode::kPrivateSetterOnly:
return "PRIVATE_SETTER_ONLY";
case VariableMode::kPrivateMethod:
return "PRIVATE_METHOD";
case VariableMode::kPrivateGetterAndSetter:
return "PRIVATE_GETTER_AND_SETTER";
case VariableMode::kConst:
return "CONST";
case VariableMode::kDynamic:
return "DYNAMIC";
case VariableMode::kDynamicGlobal:
return "DYNAMIC_GLOBAL";
case VariableMode::kDynamicLocal:
return "DYNAMIC_LOCAL";
case VariableMode::kTemporary:
return "TEMPORARY";
}
UNREACHABLE();
}
#endif
enum VariableKind : uint8_t {
NORMAL_VARIABLE,
PARAMETER_VARIABLE,
THIS_VARIABLE,
SLOPPY_BLOCK_FUNCTION_VARIABLE,
SLOPPY_FUNCTION_NAME_VARIABLE
};
inline bool IsDynamicVariableMode(VariableMode mode) {
return mode >= VariableMode::kDynamic && mode <= VariableMode::kDynamicLocal;
}
inline bool IsDeclaredVariableMode(VariableMode mode) {
STATIC_ASSERT(static_cast<uint8_t>(VariableMode::kLet) ==
0); // Implies that mode >= VariableMode::kLet.
return mode <= VariableMode::kVar;
}
inline bool IsPrivateMethodOrAccessorVariableMode(VariableMode mode) {
return mode >= VariableMode::kPrivateMethod &&
mode <= VariableMode::kPrivateGetterAndSetter;
}
inline bool IsSerializableVariableMode(VariableMode mode) {
return IsDeclaredVariableMode(mode) ||
IsPrivateMethodOrAccessorVariableMode(mode);
}
inline bool IsConstVariableMode(VariableMode mode) {
return mode == VariableMode::kConst ||
IsPrivateMethodOrAccessorVariableMode(mode);
}
inline bool IsLexicalVariableMode(VariableMode mode) {
STATIC_ASSERT(static_cast<uint8_t>(VariableMode::kLet) ==
0); // Implies that mode >= VariableMode::kLet.
return mode <= VariableMode::kLastLexicalVariableMode;
}
enum VariableLocation : uint8_t {
// Before and during variable allocation, a variable whose location is
// not yet determined. After allocation, a variable looked up as a
// property on the global object (and possibly absent). name() is the
// variable name, index() is invalid.
UNALLOCATED,
// A slot in the parameter section on the stack. index() is the
// parameter index, counting left-to-right. The receiver is index -1;
// the first parameter is index 0.
PARAMETER,
// A slot in the local section on the stack. index() is the variable
// index in the stack frame, starting at 0.
LOCAL,
// An indexed slot in a heap context. index() is the variable index in
// the context object on the heap, starting at 0. scope() is the
// corresponding scope.
CONTEXT,
// A named slot in a heap context. name() is the variable name in the
// context object on the heap, with lookup starting at the current
// context. index() is invalid.
LOOKUP,
// A named slot in a module's export table.
MODULE,
// An indexed slot in a script context. index() is the variable
// index in the context object on the heap, starting at 0.
// Important: REPL_GLOBAL variables from different scripts with the
// same name share a single script context slot. Every
// script context will reserve a slot, but only one will be used.
// REPL_GLOBAL variables are stored in script contexts, but accessed like
// globals, i.e. they always require a lookup at runtime to find the right
// script context.
REPL_GLOBAL,
kLastVariableLocation = REPL_GLOBAL
};
// ES6 specifies declarative environment records with mutable and immutable
// bindings that can be in two states: initialized and uninitialized.
// When accessing a binding, it needs to be checked for initialization.
// However in the following cases the binding is initialized immediately
// after creation so the initialization check can always be skipped:
//
// 1. Var declared local variables.
// var foo;
// 2. A local variable introduced by a function declaration.
// function foo() {}
// 3. Parameters
// function x(foo) {}
// 4. Catch bound variables.
// try {} catch (foo) {}
// 6. Function name variables of named function expressions.
// var x = function foo() {}
// 7. Implicit binding of 'this'.
// 8. Implicit binding of 'arguments' in functions.
//
// The following enum specifies a flag that indicates if the binding needs a
// distinct initialization step (kNeedsInitialization) or if the binding is
// immediately initialized upon creation (kCreatedInitialized).
enum InitializationFlag : uint8_t { kNeedsInitialization, kCreatedInitialized };
// Static variables can only be used with the class in the closest
// class scope as receivers.
enum class IsStaticFlag : uint8_t { kNotStatic, kStatic };
enum MaybeAssignedFlag : uint8_t { kNotAssigned, kMaybeAssigned };
enum class InterpreterPushArgsMode : unsigned {
kArrayFunction,
kWithFinalSpread,
kOther
};
inline size_t hash_value(InterpreterPushArgsMode mode) {
return bit_cast<unsigned>(mode);
}
inline std::ostream& operator<<(std::ostream& os,
InterpreterPushArgsMode mode) {
switch (mode) {
case InterpreterPushArgsMode::kArrayFunction:
return os << "ArrayFunction";
case InterpreterPushArgsMode::kWithFinalSpread:
return os << "WithFinalSpread";
case InterpreterPushArgsMode::kOther:
return os << "Other";
}
UNREACHABLE();
}
inline uint32_t ObjectHash(Address address) {
// All objects are at least pointer aligned, so we can remove the trailing
// zeros.
return static_cast<uint32_t>(address >> kTaggedSizeLog2);
}
// Type feedback is encoded in such a way that, we can combine the feedback
// at different points by performing an 'OR' operation. Type feedback moves
// to a more generic type when we combine feedback.
//
// kSignedSmall -> kSignedSmallInputs -> kNumber -> kNumberOrOddball -> kAny
// kString -> kAny
// kBigInt -> kAny
//
// Technically we wouldn't need the separation between the kNumber and the
// kNumberOrOddball values here, since for binary operations, we always
// truncate oddballs to numbers. In practice though it causes TurboFan to
// generate quite a lot of unused code though if we always handle numbers
// and oddballs everywhere, although in 99% of the use sites they are only
// used with numbers.
class BinaryOperationFeedback {
public:
enum {
kNone = 0x0,
kSignedSmall = 0x1,
kSignedSmallInputs = 0x3,
kNumber = 0x7,
kNumberOrOddball = 0xF,
kString = 0x10,
kBigInt = 0x20,
kAny = 0x7F
};
};
// Type feedback is encoded in such a way that, we can combine the feedback
// at different points by performing an 'OR' operation. Type feedback moves
// to a more generic type when we combine feedback.
//
// kSignedSmall -> kNumber -> kNumberOrOddball -> kAny
// kReceiver -> kReceiverOrNullOrUndefined -> kAny
// kInternalizedString -> kString -> kAny
// kSymbol -> kAny
// kBigInt -> kAny
//
// This is distinct from BinaryOperationFeedback on purpose, because the
// feedback that matters differs greatly as well as the way it is consumed.
class CompareOperationFeedback {
public:
enum {
kNone = 0x000,
kSignedSmall = 0x001,
kNumber = 0x003,
kNumberOrOddball = 0x007,
kInternalizedString = 0x008,
kString = 0x018,
kSymbol = 0x020,
kBigInt = 0x040,
kReceiver = 0x080,
kReceiverOrNullOrUndefined = 0x180,
kAny = 0x1ff
};
};
enum class Operation {
// Binary operations.
kAdd,
kSubtract,
kMultiply,
kDivide,
kModulus,
kExponentiate,
kBitwiseAnd,
kBitwiseOr,
kBitwiseXor,
kShiftLeft,
kShiftRight,
kShiftRightLogical,
// Unary operations.
kBitwiseNot,
kNegate,
kIncrement,
kDecrement,
// Compare operations.
kEqual,
kStrictEqual,
kLessThan,
kLessThanOrEqual,
kGreaterThan,
kGreaterThanOrEqual,
};
// Type feedback is encoded in such a way that, we can combine the feedback
// at different points by performing an 'OR' operation. Type feedback moves
// to a more generic type when we combine feedback.
// kNone -> kEnumCacheKeysAndIndices -> kEnumCacheKeys -> kAny
class ForInFeedback {
public:
enum {
kNone = 0x0,
kEnumCacheKeysAndIndices = 0x1,
kEnumCacheKeys = 0x3,
kAny = 0x7
};
};
STATIC_ASSERT((ForInFeedback::kNone |
ForInFeedback::kEnumCacheKeysAndIndices) ==
ForInFeedback::kEnumCacheKeysAndIndices);
STATIC_ASSERT((ForInFeedback::kEnumCacheKeysAndIndices |
ForInFeedback::kEnumCacheKeys) == ForInFeedback::kEnumCacheKeys);
STATIC_ASSERT((ForInFeedback::kEnumCacheKeys | ForInFeedback::kAny) ==
ForInFeedback::kAny);
enum class UnicodeEncoding : uint8_t {
// Different unicode encodings in a |word32|:
UTF16, // hi 16bits -> trailing surrogate or 0, low 16bits -> lead surrogate
UTF32, // full UTF32 code unit / Unicode codepoint
};
inline size_t hash_value(UnicodeEncoding encoding) {
return static_cast<uint8_t>(encoding);
}
inline std::ostream& operator<<(std::ostream& os, UnicodeEncoding encoding) {
switch (encoding) {
case UnicodeEncoding::UTF16:
return os << "UTF16";
case UnicodeEncoding::UTF32:
return os << "UTF32";
}
UNREACHABLE();
}
enum class IterationKind { kKeys, kValues, kEntries };
inline std::ostream& operator<<(std::ostream& os, IterationKind kind) {
switch (kind) {
case IterationKind::kKeys:
return os << "IterationKind::kKeys";
case IterationKind::kValues:
return os << "IterationKind::kValues";
case IterationKind::kEntries:
return os << "IterationKind::kEntries";
}
UNREACHABLE();
}
enum class CollectionKind { kMap, kSet };
inline std::ostream& operator<<(std::ostream& os, CollectionKind kind) {
switch (kind) {
case CollectionKind::kMap:
return os << "CollectionKind::kMap";
case CollectionKind::kSet:
return os << "CollectionKind::kSet";
}
UNREACHABLE();
}
// Flags for the runtime function kDefineDataPropertyInLiteral. A property can
// be enumerable or not, and, in case of functions, the function name
// can be set or not.
enum class DataPropertyInLiteralFlag {
kNoFlags = 0,
kDontEnum = 1 << 0,
kSetFunctionName = 1 << 1
};
using DataPropertyInLiteralFlags = base::Flags<DataPropertyInLiteralFlag>;
DEFINE_OPERATORS_FOR_FLAGS(DataPropertyInLiteralFlags)
enum ExternalArrayType {
kExternalInt8Array = 1,
kExternalUint8Array,
kExternalInt16Array,
kExternalUint16Array,
kExternalInt32Array,
kExternalUint32Array,
kExternalFloat32Array,
kExternalFloat64Array,
kExternalUint8ClampedArray,
kExternalBigInt64Array,
kExternalBigUint64Array,
};
struct AssemblerDebugInfo {
AssemblerDebugInfo(const char* name, const char* file, int line)
: name(name), file(file), line(line) {}
const char* name;
const char* file;
int line;
};
inline std::ostream& operator<<(std::ostream& os,
const AssemblerDebugInfo& info) {
os << "(" << info.name << ":" << info.file << ":" << info.line << ")";
return os;
}
enum class OptimizationMarker {
kLogFirstExecution,
kNone,
kCompileOptimized,
kCompileOptimizedConcurrent,
kInOptimizationQueue
};
inline std::ostream& operator<<(std::ostream& os,
const OptimizationMarker& marker) {
switch (marker) {
case OptimizationMarker::kLogFirstExecution:
return os << "OptimizationMarker::kLogFirstExecution";
case OptimizationMarker::kNone:
return os << "OptimizationMarker::kNone";
case OptimizationMarker::kCompileOptimized:
return os << "OptimizationMarker::kCompileOptimized";
case OptimizationMarker::kCompileOptimizedConcurrent:
return os << "OptimizationMarker::kCompileOptimizedConcurrent";
case OptimizationMarker::kInOptimizationQueue:
return os << "OptimizationMarker::kInOptimizationQueue";
}
UNREACHABLE();
return os;
}
enum class SpeculationMode { kAllowSpeculation, kDisallowSpeculation };
inline std::ostream& operator<<(std::ostream& os,
SpeculationMode speculation_mode) {
switch (speculation_mode) {
case SpeculationMode::kAllowSpeculation:
return os << "SpeculationMode::kAllowSpeculation";
case SpeculationMode::kDisallowSpeculation:
return os << "SpeculationMode::kDisallowSpeculation";
}
UNREACHABLE();
return os;
}
enum class BlockingBehavior { kBlock, kDontBlock };
enum class ConcurrencyMode { kNotConcurrent, kConcurrent };
#define FOR_EACH_ISOLATE_ADDRESS_NAME(C) \
C(Handler, handler) \
C(CEntryFP, c_entry_fp) \
C(CFunction, c_function) \
C(Context, context) \
C(PendingException, pending_exception) \
C(PendingHandlerContext, pending_handler_context) \
C(PendingHandlerEntrypoint, pending_handler_entrypoint) \
C(PendingHandlerConstantPool, pending_handler_constant_pool) \
C(PendingHandlerFP, pending_handler_fp) \
C(PendingHandlerSP, pending_handler_sp) \
C(ExternalCaughtException, external_caught_exception) \
C(JSEntrySP, js_entry_sp)
enum IsolateAddressId {
#define DECLARE_ENUM(CamelName, hacker_name) k##CamelName##Address,
FOR_EACH_ISOLATE_ADDRESS_NAME(DECLARE_ENUM)
#undef DECLARE_ENUM
kIsolateAddressCount
};
enum class PoisoningMitigationLevel {
kPoisonAll,
kDontPoison,
kPoisonCriticalOnly
};
enum class LoadSensitivity {
kCritical, // Critical loads are poisoned whenever we can run untrusted
// code (i.e., when --untrusted-code-mitigations is on).
kUnsafe, // Unsafe loads are poisoned when full poisoning is on
// (--branch-load-poisoning).
kSafe // Safe loads are never poisoned.
};
// The reason for a WebAssembly trap.
#define FOREACH_WASM_TRAPREASON(V) \
V(TrapUnreachable) \
V(TrapMemOutOfBounds) \
V(TrapUnalignedAccess) \
V(TrapDivByZero) \
V(TrapDivUnrepresentable) \
V(TrapRemByZero) \
V(TrapFloatUnrepresentable) \
V(TrapFuncInvalid) \
V(TrapFuncSigMismatch) \
V(TrapDataSegmentDropped) \
V(TrapElemSegmentDropped) \
V(TrapTableOutOfBounds) \
V(TrapBrOnExnNullRef) \
V(TrapRethrowNullRef)
enum KeyedAccessLoadMode {
STANDARD_LOAD,
LOAD_IGNORE_OUT_OF_BOUNDS,
};
enum KeyedAccessStoreMode {
STANDARD_STORE,
STORE_AND_GROW_HANDLE_COW,
STORE_IGNORE_OUT_OF_BOUNDS,
STORE_HANDLE_COW
};
enum MutableMode { MUTABLE, IMMUTABLE };
inline bool IsCOWHandlingStoreMode(KeyedAccessStoreMode store_mode) {
return store_mode == STORE_HANDLE_COW ||
store_mode == STORE_AND_GROW_HANDLE_COW;
}
inline bool IsGrowStoreMode(KeyedAccessStoreMode store_mode) {
return store_mode == STORE_AND_GROW_HANDLE_COW;
}
enum IcCheckType { ELEMENT, PROPERTY };
// Helper stubs can be called in different ways depending on where the target
// code is located and how the call sequence is expected to look like:
// - CodeObject: Call on-heap {Code} object via {RelocInfo::CODE_TARGET}.
// - WasmRuntimeStub: Call native {WasmCode} stub via
// {RelocInfo::WASM_STUB_CALL}.
// - BuiltinPointer: Call a builtin based on a builtin pointer with dynamic
// contents. If builtins are embedded, we call directly into off-heap code
// without going through the on-heap Code trampoline.
enum class StubCallMode {
kCallCodeObject,
kCallWasmRuntimeStub,
kCallBuiltinPointer,
};
constexpr int kFunctionLiteralIdInvalid = -1;
constexpr int kFunctionLiteralIdTopLevel = 0;
constexpr int kSmallOrderedHashSetMinCapacity = 4;
constexpr int kSmallOrderedHashMapMinCapacity = 4;
static const uint16_t kDontAdaptArgumentsSentinel = static_cast<uint16_t>(-1);
// Opaque data type for identifying stack frames. Used extensively
// by the debugger.
// ID_MIN_VALUE and ID_MAX_VALUE are specified to ensure that enumeration type
// has correct value range (see Issue 830 for more details).
enum StackFrameId { ID_MIN_VALUE = kMinInt, ID_MAX_VALUE = kMaxInt, NO_ID = 0 };
enum class ExceptionStatus : bool { kException = false, kSuccess = true };
V8_INLINE bool operator!(ExceptionStatus status) {
return !static_cast<bool>(status);
}
enum class TraceRetainingPathMode { kEnabled, kDisabled };
// Used in the ScopeInfo flags fields for the function name variable for named
// function expressions, and for the receiver. Must be declared here so that it
// can be used in Torque.
enum class VariableAllocationInfo { NONE, STACK, CONTEXT, UNUSED };
} // namespace internal
} // namespace v8
namespace i = v8::internal;
#endif // V8_COMMON_GLOBALS_H_
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