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v8/src/assembler.cc

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// Copyright (c) 1994-2006 Sun Microsystems Inc.
// 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.
//
// - Redistribution 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 Sun Microsystems or the names of 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.
// The original source code covered by the above license above has been
// modified significantly by Google Inc.
// Copyright 2012 the V8 project authors. All rights reserved.
#include "assembler.h"
#include <cmath>
#include "api.h"
#include "builtins.h"
#include "counters.h"
#include "cpu.h"
#include "debug.h"
#include "deoptimizer.h"
#include "execution.h"
#include "ic.h"
#include "isolate-inl.h"
#include "jsregexp.h"
#include "lazy-instance.h"
#include "platform.h"
#include "regexp-macro-assembler.h"
#include "regexp-stack.h"
#include "runtime.h"
#include "serialize.h"
#include "store-buffer-inl.h"
#include "stub-cache.h"
#include "token.h"
#if V8_TARGET_ARCH_IA32
#include "ia32/assembler-ia32-inl.h"
#elif V8_TARGET_ARCH_X64
#include "x64/assembler-x64-inl.h"
#elif V8_TARGET_ARCH_ARM
#include "arm/assembler-arm-inl.h"
#elif V8_TARGET_ARCH_MIPS
#include "mips/assembler-mips-inl.h"
#else
#error "Unknown architecture."
#endif
// Include native regexp-macro-assembler.
#ifndef V8_INTERPRETED_REGEXP
#if V8_TARGET_ARCH_IA32
#include "ia32/regexp-macro-assembler-ia32.h"
#elif V8_TARGET_ARCH_X64
#include "x64/regexp-macro-assembler-x64.h"
#elif V8_TARGET_ARCH_ARM
#include "arm/regexp-macro-assembler-arm.h"
#elif V8_TARGET_ARCH_MIPS
#include "mips/regexp-macro-assembler-mips.h"
#else // Unknown architecture.
#error "Unknown architecture."
#endif // Target architecture.
#endif // V8_INTERPRETED_REGEXP
namespace v8 {
namespace internal {
// -----------------------------------------------------------------------------
// Common double constants.
struct DoubleConstant BASE_EMBEDDED {
double min_int;
double one_half;
double minus_one_half;
double minus_zero;
double zero;
double uint8_max_value;
double negative_infinity;
double canonical_non_hole_nan;
double the_hole_nan;
double uint32_bias;
};
static DoubleConstant double_constants;
const char* const RelocInfo::kFillerCommentString = "DEOPTIMIZATION PADDING";
static bool math_exp_data_initialized = false;
static Mutex* math_exp_data_mutex = NULL;
static double* math_exp_constants_array = NULL;
static double* math_exp_log_table_array = NULL;
// -----------------------------------------------------------------------------
// Implementation of AssemblerBase
AssemblerBase::AssemblerBase(Isolate* isolate, void* buffer, int buffer_size)
: isolate_(isolate),
jit_cookie_(0),
enabled_cpu_features_(0),
emit_debug_code_(FLAG_debug_code),
predictable_code_size_(false) {
if (FLAG_mask_constants_with_cookie && isolate != NULL) {
jit_cookie_ = isolate->random_number_generator()->NextInt();
}
if (buffer == NULL) {
// Do our own buffer management.
if (buffer_size <= kMinimalBufferSize) {
buffer_size = kMinimalBufferSize;
if (isolate->assembler_spare_buffer() != NULL) {
buffer = isolate->assembler_spare_buffer();
isolate->set_assembler_spare_buffer(NULL);
}
}
if (buffer == NULL) buffer = NewArray<byte>(buffer_size);
own_buffer_ = true;
} else {
// Use externally provided buffer instead.
ASSERT(buffer_size > 0);
own_buffer_ = false;
}
buffer_ = static_cast<byte*>(buffer);
buffer_size_ = buffer_size;
pc_ = buffer_;
}
AssemblerBase::~AssemblerBase() {
if (own_buffer_) {
if (isolate() != NULL &&
isolate()->assembler_spare_buffer() == NULL &&
buffer_size_ == kMinimalBufferSize) {
isolate()->set_assembler_spare_buffer(buffer_);
} else {
DeleteArray(buffer_);
}
}
}
// -----------------------------------------------------------------------------
// Implementation of PredictableCodeSizeScope
PredictableCodeSizeScope::PredictableCodeSizeScope(AssemblerBase* assembler,
int expected_size)
: assembler_(assembler),
expected_size_(expected_size),
start_offset_(assembler->pc_offset()),
old_value_(assembler->predictable_code_size()) {
assembler_->set_predictable_code_size(true);
}
PredictableCodeSizeScope::~PredictableCodeSizeScope() {
// TODO(svenpanne) Remove the 'if' when everything works.
if (expected_size_ >= 0) {
CHECK_EQ(expected_size_, assembler_->pc_offset() - start_offset_);
}
assembler_->set_predictable_code_size(old_value_);
}
// -----------------------------------------------------------------------------
// Implementation of CpuFeatureScope
#ifdef DEBUG
CpuFeatureScope::CpuFeatureScope(AssemblerBase* assembler, CpuFeature f)
: assembler_(assembler) {
ASSERT(CpuFeatures::IsSafeForSnapshot(f));
old_enabled_ = assembler_->enabled_cpu_features();
uint64_t mask = static_cast<uint64_t>(1) << f;
// TODO(svenpanne) This special case below doesn't belong here!
#if V8_TARGET_ARCH_ARM
// ARMv7 is implied by VFP3.
if (f == VFP3) {
mask |= static_cast<uint64_t>(1) << ARMv7;
}
#endif
assembler_->set_enabled_cpu_features(old_enabled_ | mask);
}
CpuFeatureScope::~CpuFeatureScope() {
assembler_->set_enabled_cpu_features(old_enabled_);
}
#endif
// -----------------------------------------------------------------------------
// Implementation of PlatformFeatureScope
PlatformFeatureScope::PlatformFeatureScope(CpuFeature f)
: old_cross_compile_(CpuFeatures::cross_compile_) {
// CpuFeatures is a global singleton, therefore this is only safe in
// single threaded code.
ASSERT(Serializer::enabled());
uint64_t mask = static_cast<uint64_t>(1) << f;
CpuFeatures::cross_compile_ |= mask;
}
PlatformFeatureScope::~PlatformFeatureScope() {
CpuFeatures::cross_compile_ = old_cross_compile_;
}
// -----------------------------------------------------------------------------
// Implementation of Label
int Label::pos() const {
if (pos_ < 0) return -pos_ - 1;
if (pos_ > 0) return pos_ - 1;
UNREACHABLE();
return 0;
}
// -----------------------------------------------------------------------------
// Implementation of RelocInfoWriter and RelocIterator
//
// Relocation information is written backwards in memory, from high addresses
// towards low addresses, byte by byte. Therefore, in the encodings listed
// below, the first byte listed it at the highest address, and successive
// bytes in the record are at progressively lower addresses.
//
// Encoding
//
// The most common modes are given single-byte encodings. Also, it is
// easy to identify the type of reloc info and skip unwanted modes in
// an iteration.
//
// The encoding relies on the fact that there are fewer than 14
// different relocation modes using standard non-compact encoding.
//
// The first byte of a relocation record has a tag in its low 2 bits:
// Here are the record schemes, depending on the low tag and optional higher
// tags.
//
// Low tag:
// 00: embedded_object: [6-bit pc delta] 00
//
// 01: code_target: [6-bit pc delta] 01
//
// 10: short_data_record: [6-bit pc delta] 10 followed by
// [6-bit data delta] [2-bit data type tag]
//
// 11: long_record [2-bit high tag][4 bit middle_tag] 11
// followed by variable data depending on type.
//
// 2-bit data type tags, used in short_data_record and data_jump long_record:
// code_target_with_id: 00
// position: 01
// statement_position: 10
// comment: 11 (not used in short_data_record)
//
// Long record format:
// 4-bit middle_tag:
// 0000 - 1100 : Short record for RelocInfo::Mode middle_tag + 2
// (The middle_tag encodes rmode - RelocInfo::LAST_COMPACT_ENUM,
// and is between 0000 and 1100)
// The format is:
// 00 [4 bit middle_tag] 11 followed by
// 00 [6 bit pc delta]
//
// 1101: constant pool. Used on ARM only for now.
// The format is: 11 1101 11
// signed int (size of the constant pool).
// 1110: long_data_record
// The format is: [2-bit data_type_tag] 1110 11
// signed intptr_t, lowest byte written first
// (except data_type code_target_with_id, which
// is followed by a signed int, not intptr_t.)
//
// 1111: long_pc_jump
// The format is:
// pc-jump: 00 1111 11,
// 00 [6 bits pc delta]
// or
// pc-jump (variable length):
// 01 1111 11,
// [7 bits data] 0
// ...
// [7 bits data] 1
// (Bits 6..31 of pc delta, with leading zeroes
// dropped, and last non-zero chunk tagged with 1.)
const int kMaxStandardNonCompactModes = 14;
const int kTagBits = 2;
const int kTagMask = (1 << kTagBits) - 1;
const int kExtraTagBits = 4;
const int kLocatableTypeTagBits = 2;
const int kSmallDataBits = kBitsPerByte - kLocatableTypeTagBits;
const int kEmbeddedObjectTag = 0;
const int kCodeTargetTag = 1;
const int kLocatableTag = 2;
const int kDefaultTag = 3;
const int kPCJumpExtraTag = (1 << kExtraTagBits) - 1;
const int kSmallPCDeltaBits = kBitsPerByte - kTagBits;
const int kSmallPCDeltaMask = (1 << kSmallPCDeltaBits) - 1;
const int RelocInfo::kMaxSmallPCDelta = kSmallPCDeltaMask;
const int kVariableLengthPCJumpTopTag = 1;
const int kChunkBits = 7;
const int kChunkMask = (1 << kChunkBits) - 1;
const int kLastChunkTagBits = 1;
const int kLastChunkTagMask = 1;
const int kLastChunkTag = 1;
const int kDataJumpExtraTag = kPCJumpExtraTag - 1;
const int kCodeWithIdTag = 0;
const int kNonstatementPositionTag = 1;
const int kStatementPositionTag = 2;
const int kCommentTag = 3;
const int kConstPoolExtraTag = kPCJumpExtraTag - 2;
const int kConstPoolTag = 3;
uint32_t RelocInfoWriter::WriteVariableLengthPCJump(uint32_t pc_delta) {
// Return if the pc_delta can fit in kSmallPCDeltaBits bits.
// Otherwise write a variable length PC jump for the bits that do
// not fit in the kSmallPCDeltaBits bits.
if (is_uintn(pc_delta, kSmallPCDeltaBits)) return pc_delta;
WriteExtraTag(kPCJumpExtraTag, kVariableLengthPCJumpTopTag);
uint32_t pc_jump = pc_delta >> kSmallPCDeltaBits;
ASSERT(pc_jump > 0);
// Write kChunkBits size chunks of the pc_jump.
for (; pc_jump > 0; pc_jump = pc_jump >> kChunkBits) {
byte b = pc_jump & kChunkMask;
*--pos_ = b << kLastChunkTagBits;
}
// Tag the last chunk so it can be identified.
*pos_ = *pos_ | kLastChunkTag;
// Return the remaining kSmallPCDeltaBits of the pc_delta.
return pc_delta & kSmallPCDeltaMask;
}
void RelocInfoWriter::WriteTaggedPC(uint32_t pc_delta, int tag) {
// Write a byte of tagged pc-delta, possibly preceded by var. length pc-jump.
pc_delta = WriteVariableLengthPCJump(pc_delta);
*--pos_ = pc_delta << kTagBits | tag;
}
void RelocInfoWriter::WriteTaggedData(intptr_t data_delta, int tag) {
*--pos_ = static_cast<byte>(data_delta << kLocatableTypeTagBits | tag);
}
void RelocInfoWriter::WriteExtraTag(int extra_tag, int top_tag) {
*--pos_ = static_cast<int>(top_tag << (kTagBits + kExtraTagBits) |
extra_tag << kTagBits |
kDefaultTag);
}
void RelocInfoWriter::WriteExtraTaggedPC(uint32_t pc_delta, int extra_tag) {
// Write two-byte tagged pc-delta, possibly preceded by var. length pc-jump.
pc_delta = WriteVariableLengthPCJump(pc_delta);
WriteExtraTag(extra_tag, 0);
*--pos_ = pc_delta;
}
void RelocInfoWriter::WriteExtraTaggedIntData(int data_delta, int top_tag) {
WriteExtraTag(kDataJumpExtraTag, top_tag);
for (int i = 0; i < kIntSize; i++) {
*--pos_ = static_cast<byte>(data_delta);
// Signed right shift is arithmetic shift. Tested in test-utils.cc.
data_delta = data_delta >> kBitsPerByte;
}
}
void RelocInfoWriter::WriteExtraTaggedConstPoolData(int data) {
WriteExtraTag(kConstPoolExtraTag, kConstPoolTag);
for (int i = 0; i < kIntSize; i++) {
*--pos_ = static_cast<byte>(data);
// Signed right shift is arithmetic shift. Tested in test-utils.cc.
data = data >> kBitsPerByte;
}
}
void RelocInfoWriter::WriteExtraTaggedData(intptr_t data_delta, int top_tag) {
WriteExtraTag(kDataJumpExtraTag, top_tag);
for (int i = 0; i < kIntptrSize; i++) {
*--pos_ = static_cast<byte>(data_delta);
// Signed right shift is arithmetic shift. Tested in test-utils.cc.
data_delta = data_delta >> kBitsPerByte;
}
}
void RelocInfoWriter::Write(const RelocInfo* rinfo) {
#ifdef DEBUG
byte* begin_pos = pos_;
#endif
ASSERT(rinfo->rmode() < RelocInfo::NUMBER_OF_MODES);
ASSERT(rinfo->pc() - last_pc_ >= 0);
ASSERT(RelocInfo::LAST_STANDARD_NONCOMPACT_ENUM - RelocInfo::LAST_COMPACT_ENUM
<= kMaxStandardNonCompactModes);
// Use unsigned delta-encoding for pc.
uint32_t pc_delta = static_cast<uint32_t>(rinfo->pc() - last_pc_);
RelocInfo::Mode rmode = rinfo->rmode();
// The two most common modes are given small tags, and usually fit in a byte.
if (rmode == RelocInfo::EMBEDDED_OBJECT) {
WriteTaggedPC(pc_delta, kEmbeddedObjectTag);
} else if (rmode == RelocInfo::CODE_TARGET) {
WriteTaggedPC(pc_delta, kCodeTargetTag);
ASSERT(begin_pos - pos_ <= RelocInfo::kMaxCallSize);
} else if (rmode == RelocInfo::CODE_TARGET_WITH_ID) {
// Use signed delta-encoding for id.
ASSERT(static_cast<int>(rinfo->data()) == rinfo->data());
int id_delta = static_cast<int>(rinfo->data()) - last_id_;
// Check if delta is small enough to fit in a tagged byte.
if (is_intn(id_delta, kSmallDataBits)) {
WriteTaggedPC(pc_delta, kLocatableTag);
WriteTaggedData(id_delta, kCodeWithIdTag);
} else {
// Otherwise, use costly encoding.
WriteExtraTaggedPC(pc_delta, kPCJumpExtraTag);
WriteExtraTaggedIntData(id_delta, kCodeWithIdTag);
}
last_id_ = static_cast<int>(rinfo->data());
} else if (RelocInfo::IsPosition(rmode)) {
// Use signed delta-encoding for position.
ASSERT(static_cast<int>(rinfo->data()) == rinfo->data());
int pos_delta = static_cast<int>(rinfo->data()) - last_position_;
int pos_type_tag = (rmode == RelocInfo::POSITION) ? kNonstatementPositionTag
: kStatementPositionTag;
// Check if delta is small enough to fit in a tagged byte.
if (is_intn(pos_delta, kSmallDataBits)) {
WriteTaggedPC(pc_delta, kLocatableTag);
WriteTaggedData(pos_delta, pos_type_tag);
} else {
// Otherwise, use costly encoding.
WriteExtraTaggedPC(pc_delta, kPCJumpExtraTag);
WriteExtraTaggedIntData(pos_delta, pos_type_tag);
}
last_position_ = static_cast<int>(rinfo->data());
} else if (RelocInfo::IsComment(rmode)) {
// Comments are normally not generated, so we use the costly encoding.
WriteExtraTaggedPC(pc_delta, kPCJumpExtraTag);
WriteExtraTaggedData(rinfo->data(), kCommentTag);
ASSERT(begin_pos - pos_ >= RelocInfo::kMinRelocCommentSize);
} else if (RelocInfo::IsConstPool(rmode)) {
WriteExtraTaggedPC(pc_delta, kPCJumpExtraTag);
WriteExtraTaggedConstPoolData(static_cast<int>(rinfo->data()));
} else {
ASSERT(rmode > RelocInfo::LAST_COMPACT_ENUM);
int saved_mode = rmode - RelocInfo::LAST_COMPACT_ENUM;
// For all other modes we simply use the mode as the extra tag.
// None of these modes need a data component.
ASSERT(saved_mode < kPCJumpExtraTag && saved_mode < kDataJumpExtraTag);
WriteExtraTaggedPC(pc_delta, saved_mode);
}
last_pc_ = rinfo->pc();
#ifdef DEBUG
ASSERT(begin_pos - pos_ <= kMaxSize);
#endif
}
inline int RelocIterator::AdvanceGetTag() {
return *--pos_ & kTagMask;
}
inline int RelocIterator::GetExtraTag() {
return (*pos_ >> kTagBits) & ((1 << kExtraTagBits) - 1);
}
inline int RelocIterator::GetTopTag() {
return *pos_ >> (kTagBits + kExtraTagBits);
}
inline void RelocIterator::ReadTaggedPC() {
rinfo_.pc_ += *pos_ >> kTagBits;
}
inline void RelocIterator::AdvanceReadPC() {
rinfo_.pc_ += *--pos_;
}
void RelocIterator::AdvanceReadId() {
int x = 0;
for (int i = 0; i < kIntSize; i++) {
x |= static_cast<int>(*--pos_) << i * kBitsPerByte;
}
last_id_ += x;
rinfo_.data_ = last_id_;
}
void RelocIterator::AdvanceReadConstPoolData() {
int x = 0;
for (int i = 0; i < kIntSize; i++) {
x |= static_cast<int>(*--pos_) << i * kBitsPerByte;
}
rinfo_.data_ = x;
}
void RelocIterator::AdvanceReadPosition() {
int x = 0;
for (int i = 0; i < kIntSize; i++) {
x |= static_cast<int>(*--pos_) << i * kBitsPerByte;
}
last_position_ += x;
rinfo_.data_ = last_position_;
}
void RelocIterator::AdvanceReadData() {
intptr_t x = 0;
for (int i = 0; i < kIntptrSize; i++) {
x |= static_cast<intptr_t>(*--pos_) << i * kBitsPerByte;
}
rinfo_.data_ = x;
}
void RelocIterator::AdvanceReadVariableLengthPCJump() {
// Read the 32-kSmallPCDeltaBits most significant bits of the
// pc jump in kChunkBits bit chunks and shift them into place.
// Stop when the last chunk is encountered.
uint32_t pc_jump = 0;
for (int i = 0; i < kIntSize; i++) {
byte pc_jump_part = *--pos_;
pc_jump |= (pc_jump_part >> kLastChunkTagBits) << i * kChunkBits;
if ((pc_jump_part & kLastChunkTagMask) == 1) break;
}
// The least significant kSmallPCDeltaBits bits will be added
// later.
rinfo_.pc_ += pc_jump << kSmallPCDeltaBits;
}
inline int RelocIterator::GetLocatableTypeTag() {
return *pos_ & ((1 << kLocatableTypeTagBits) - 1);
}
inline void RelocIterator::ReadTaggedId() {
int8_t signed_b = *pos_;
// Signed right shift is arithmetic shift. Tested in test-utils.cc.
last_id_ += signed_b >> kLocatableTypeTagBits;
rinfo_.data_ = last_id_;
}
inline void RelocIterator::ReadTaggedPosition() {
int8_t signed_b = *pos_;
// Signed right shift is arithmetic shift. Tested in test-utils.cc.
last_position_ += signed_b >> kLocatableTypeTagBits;
rinfo_.data_ = last_position_;
}
static inline RelocInfo::Mode GetPositionModeFromTag(int tag) {
ASSERT(tag == kNonstatementPositionTag ||
tag == kStatementPositionTag);
return (tag == kNonstatementPositionTag) ?
RelocInfo::POSITION :
RelocInfo::STATEMENT_POSITION;
}
void RelocIterator::next() {
ASSERT(!done());
// Basically, do the opposite of RelocInfoWriter::Write.
// Reading of data is as far as possible avoided for unwanted modes,
// but we must always update the pc.
//
// We exit this loop by returning when we find a mode we want.
while (pos_ > end_) {
int tag = AdvanceGetTag();
if (tag == kEmbeddedObjectTag) {
ReadTaggedPC();
if (SetMode(RelocInfo::EMBEDDED_OBJECT)) return;
} else if (tag == kCodeTargetTag) {
ReadTaggedPC();
if (SetMode(RelocInfo::CODE_TARGET)) return;
} else if (tag == kLocatableTag) {
ReadTaggedPC();
Advance();
int locatable_tag = GetLocatableTypeTag();
if (locatable_tag == kCodeWithIdTag) {
if (SetMode(RelocInfo::CODE_TARGET_WITH_ID)) {
ReadTaggedId();
return;
}
} else {
// Compact encoding is never used for comments,
// so it must be a position.
ASSERT(locatable_tag == kNonstatementPositionTag ||
locatable_tag == kStatementPositionTag);
if (mode_mask_ & RelocInfo::kPositionMask) {
ReadTaggedPosition();
if (SetMode(GetPositionModeFromTag(locatable_tag))) return;
}
}
} else {
ASSERT(tag == kDefaultTag);
int extra_tag = GetExtraTag();
if (extra_tag == kPCJumpExtraTag) {
if (GetTopTag() == kVariableLengthPCJumpTopTag) {
AdvanceReadVariableLengthPCJump();
} else {
AdvanceReadPC();
}
} else if (extra_tag == kDataJumpExtraTag) {
int locatable_tag = GetTopTag();
if (locatable_tag == kCodeWithIdTag) {
if (SetMode(RelocInfo::CODE_TARGET_WITH_ID)) {
AdvanceReadId();
return;
}
Advance(kIntSize);
} else if (locatable_tag != kCommentTag) {
ASSERT(locatable_tag == kNonstatementPositionTag ||
locatable_tag == kStatementPositionTag);
if (mode_mask_ & RelocInfo::kPositionMask) {
AdvanceReadPosition();
if (SetMode(GetPositionModeFromTag(locatable_tag))) return;
} else {
Advance(kIntSize);
}
} else {
ASSERT(locatable_tag == kCommentTag);
if (SetMode(RelocInfo::COMMENT)) {
AdvanceReadData();
return;
}
Advance(kIntptrSize);
}
} else if ((extra_tag == kConstPoolExtraTag) &&
(GetTopTag() == kConstPoolTag)) {
if (SetMode(RelocInfo::CONST_POOL)) {
AdvanceReadConstPoolData();
return;
}
Advance(kIntSize);
} else {
AdvanceReadPC();
int rmode = extra_tag + RelocInfo::LAST_COMPACT_ENUM;
if (SetMode(static_cast<RelocInfo::Mode>(rmode))) return;
}
}
}
if (code_age_sequence_ != NULL) {
byte* old_code_age_sequence = code_age_sequence_;
code_age_sequence_ = NULL;
if (SetMode(RelocInfo::CODE_AGE_SEQUENCE)) {
rinfo_.data_ = 0;
rinfo_.pc_ = old_code_age_sequence;
return;
}
}
done_ = true;
}
RelocIterator::RelocIterator(Code* code, int mode_mask) {
rinfo_.host_ = code;
rinfo_.pc_ = code->instruction_start();
rinfo_.data_ = 0;
// Relocation info is read backwards.
pos_ = code->relocation_start() + code->relocation_size();
end_ = code->relocation_start();
done_ = false;
mode_mask_ = mode_mask;
last_id_ = 0;
last_position_ = 0;
byte* sequence = code->FindCodeAgeSequence();
if (sequence != NULL && !Code::IsYoungSequence(sequence)) {
code_age_sequence_ = sequence;
} else {
code_age_sequence_ = NULL;
}
if (mode_mask_ == 0) pos_ = end_;
next();
}
RelocIterator::RelocIterator(const CodeDesc& desc, int mode_mask) {
rinfo_.pc_ = desc.buffer;
rinfo_.data_ = 0;
// Relocation info is read backwards.
pos_ = desc.buffer + desc.buffer_size;
end_ = pos_ - desc.reloc_size;
done_ = false;
mode_mask_ = mode_mask;
last_id_ = 0;
last_position_ = 0;
code_age_sequence_ = NULL;
if (mode_mask_ == 0) pos_ = end_;
next();
}
// -----------------------------------------------------------------------------
// Implementation of RelocInfo
#ifdef DEBUG
bool RelocInfo::RequiresRelocation(const CodeDesc& desc) {
// Ensure there are no code targets or embedded objects present in the
// deoptimization entries, they would require relocation after code
// generation.
int mode_mask = RelocInfo::kCodeTargetMask |
RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
RelocInfo::ModeMask(RelocInfo::CELL) |
RelocInfo::kApplyMask;
RelocIterator it(desc, mode_mask);
return !it.done();
}
#endif
#ifdef ENABLE_DISASSEMBLER
const char* RelocInfo::RelocModeName(RelocInfo::Mode rmode) {
switch (rmode) {
case RelocInfo::NONE32:
return "no reloc 32";
case RelocInfo::NONE64:
return "no reloc 64";
case RelocInfo::EMBEDDED_OBJECT:
return "embedded object";
case RelocInfo::CONSTRUCT_CALL:
return "code target (js construct call)";
case RelocInfo::CODE_TARGET_CONTEXT:
return "code target (context)";
case RelocInfo::DEBUG_BREAK:
#ifndef ENABLE_DEBUGGER_SUPPORT
UNREACHABLE();
#endif
return "debug break";
case RelocInfo::CODE_TARGET:
return "code target";
case RelocInfo::CODE_TARGET_WITH_ID:
return "code target with id";
case RelocInfo::CELL:
return "property cell";
case RelocInfo::RUNTIME_ENTRY:
return "runtime entry";
case RelocInfo::JS_RETURN:
return "js return";
case RelocInfo::COMMENT:
return "comment";
case RelocInfo::POSITION:
return "position";
case RelocInfo::STATEMENT_POSITION:
return "statement position";
case RelocInfo::EXTERNAL_REFERENCE:
return "external reference";
case RelocInfo::INTERNAL_REFERENCE:
return "internal reference";
case RelocInfo::CONST_POOL:
return "constant pool";
case RelocInfo::DEBUG_BREAK_SLOT:
#ifndef ENABLE_DEBUGGER_SUPPORT
UNREACHABLE();
#endif
return "debug break slot";
case RelocInfo::CODE_AGE_SEQUENCE:
return "code_age_sequence";
case RelocInfo::NUMBER_OF_MODES:
UNREACHABLE();
return "number_of_modes";
}
return "unknown relocation type";
}
void RelocInfo::Print(Isolate* isolate, FILE* out) {
PrintF(out, "%p %s", pc_, RelocModeName(rmode_));
if (IsComment(rmode_)) {
PrintF(out, " (%s)", reinterpret_cast<char*>(data_));
} else if (rmode_ == EMBEDDED_OBJECT) {
PrintF(out, " (");
target_object()->ShortPrint(out);
PrintF(out, ")");
} else if (rmode_ == EXTERNAL_REFERENCE) {
ExternalReferenceEncoder ref_encoder(isolate);
PrintF(out, " (%s) (%p)",
ref_encoder.NameOfAddress(target_reference()),
target_reference());
} else if (IsCodeTarget(rmode_)) {
Code* code = Code::GetCodeFromTargetAddress(target_address());
PrintF(out, " (%s) (%p)", Code::Kind2String(code->kind()),
target_address());
if (rmode_ == CODE_TARGET_WITH_ID) {
PrintF(out, " (id=%d)", static_cast<int>(data_));
}
} else if (IsPosition(rmode_)) {
PrintF(out, " (%" V8_PTR_PREFIX "d)", data());
} else if (IsRuntimeEntry(rmode_) &&
isolate->deoptimizer_data() != NULL) {
// Depotimization bailouts are stored as runtime entries.
int id = Deoptimizer::GetDeoptimizationId(
isolate, target_address(), Deoptimizer::EAGER);
if (id != Deoptimizer::kNotDeoptimizationEntry) {
PrintF(out, " (deoptimization bailout %d)", id);
}
}
PrintF(out, "\n");
}
#endif // ENABLE_DISASSEMBLER
#ifdef VERIFY_HEAP
void RelocInfo::Verify() {
switch (rmode_) {
case EMBEDDED_OBJECT:
Object::VerifyPointer(target_object());
break;
case CELL:
Object::VerifyPointer(target_cell());
break;
case DEBUG_BREAK:
#ifndef ENABLE_DEBUGGER_SUPPORT
UNREACHABLE();
break;
#endif
case CONSTRUCT_CALL:
case CODE_TARGET_CONTEXT:
case CODE_TARGET_WITH_ID:
case CODE_TARGET: {
// convert inline target address to code object
Address addr = target_address();
CHECK(addr != NULL);
// Check that we can find the right code object.
Code* code = Code::GetCodeFromTargetAddress(addr);
Object* found = code->GetIsolate()->FindCodeObject(addr);
CHECK(found->IsCode());
CHECK(code->address() == HeapObject::cast(found)->address());
break;
}
case RUNTIME_ENTRY:
case JS_RETURN:
case COMMENT:
case POSITION:
case STATEMENT_POSITION:
case EXTERNAL_REFERENCE:
case INTERNAL_REFERENCE:
case CONST_POOL:
case DEBUG_BREAK_SLOT:
case NONE32:
case NONE64:
break;
case NUMBER_OF_MODES:
UNREACHABLE();
break;
case CODE_AGE_SEQUENCE:
ASSERT(Code::IsYoungSequence(pc_) || code_age_stub()->IsCode());
break;
}
}
#endif // VERIFY_HEAP
// -----------------------------------------------------------------------------
// Implementation of ExternalReference
void ExternalReference::SetUp() {
double_constants.min_int = kMinInt;
double_constants.one_half = 0.5;
double_constants.minus_one_half = -0.5;
double_constants.minus_zero = -0.0;
double_constants.uint8_max_value = 255;
double_constants.zero = 0.0;
double_constants.canonical_non_hole_nan = OS::nan_value();
double_constants.the_hole_nan = BitCast<double>(kHoleNanInt64);
double_constants.negative_infinity = -V8_INFINITY;
double_constants.uint32_bias =
static_cast<double>(static_cast<uint32_t>(0xFFFFFFFF)) + 1;
math_exp_data_mutex = new Mutex();
}
void ExternalReference::InitializeMathExpData() {
// Early return?
if (math_exp_data_initialized) return;
LockGuard<Mutex> lock_guard(math_exp_data_mutex);
if (!math_exp_data_initialized) {
// If this is changed, generated code must be adapted too.
const int kTableSizeBits = 11;
const int kTableSize = 1 << kTableSizeBits;
const double kTableSizeDouble = static_cast<double>(kTableSize);
math_exp_constants_array = new double[9];
// Input values smaller than this always return 0.
math_exp_constants_array[0] = -708.39641853226408;
// Input values larger than this always return +Infinity.
math_exp_constants_array[1] = 709.78271289338397;
math_exp_constants_array[2] = V8_INFINITY;
// The rest is black magic. Do not attempt to understand it. It is
// loosely based on the "expd" function published at:
// http://herumi.blogspot.com/2011/08/fast-double-precision-exponential.html
const double constant3 = (1 << kTableSizeBits) / log(2.0);
math_exp_constants_array[3] = constant3;
math_exp_constants_array[4] =
static_cast<double>(static_cast<int64_t>(3) << 51);
math_exp_constants_array[5] = 1 / constant3;
math_exp_constants_array[6] = 3.0000000027955394;
math_exp_constants_array[7] = 0.16666666685227835;
math_exp_constants_array[8] = 1;
math_exp_log_table_array = new double[kTableSize];
for (int i = 0; i < kTableSize; i++) {
double value = pow(2, i / kTableSizeDouble);
uint64_t bits = BitCast<uint64_t, double>(value);
bits &= (static_cast<uint64_t>(1) << 52) - 1;
double mantissa = BitCast<double, uint64_t>(bits);
math_exp_log_table_array[i] = mantissa;
}
math_exp_data_initialized = true;
}
}
void ExternalReference::TearDownMathExpData() {
delete[] math_exp_constants_array;
delete[] math_exp_log_table_array;
delete math_exp_data_mutex;
}
ExternalReference::ExternalReference(Builtins::CFunctionId id, Isolate* isolate)
: address_(Redirect(isolate, Builtins::c_function_address(id))) {}
ExternalReference::ExternalReference(
ApiFunction* fun,
Type type = ExternalReference::BUILTIN_CALL,
Isolate* isolate = NULL)
: address_(Redirect(isolate, fun->address(), type)) {}
ExternalReference::ExternalReference(Builtins::Name name, Isolate* isolate)
: address_(isolate->builtins()->builtin_address(name)) {}
ExternalReference::ExternalReference(Runtime::FunctionId id,
Isolate* isolate)
: address_(Redirect(isolate, Runtime::FunctionForId(id)->entry)) {}
ExternalReference::ExternalReference(const Runtime::Function* f,
Isolate* isolate)
: address_(Redirect(isolate, f->entry)) {}
ExternalReference ExternalReference::isolate_address(Isolate* isolate) {
return ExternalReference(isolate);
}
ExternalReference::ExternalReference(const IC_Utility& ic_utility,
Isolate* isolate)
: address_(Redirect(isolate, ic_utility.address())) {}
#ifdef ENABLE_DEBUGGER_SUPPORT
ExternalReference::ExternalReference(const Debug_Address& debug_address,
Isolate* isolate)
: address_(debug_address.address(isolate)) {}
#endif
ExternalReference::ExternalReference(StatsCounter* counter)
: address_(reinterpret_cast<Address>(counter->GetInternalPointer())) {}
ExternalReference::ExternalReference(Isolate::AddressId id, Isolate* isolate)
: address_(isolate->get_address_from_id(id)) {}
ExternalReference::ExternalReference(const SCTableReference& table_ref)
: address_(table_ref.address()) {}
ExternalReference ExternalReference::
incremental_marking_record_write_function(Isolate* isolate) {
return ExternalReference(Redirect(
isolate,
FUNCTION_ADDR(IncrementalMarking::RecordWriteFromCode)));
}
ExternalReference ExternalReference::
incremental_evacuation_record_write_function(Isolate* isolate) {
return ExternalReference(Redirect(
isolate,
FUNCTION_ADDR(IncrementalMarking::RecordWriteForEvacuationFromCode)));
}
ExternalReference ExternalReference::
store_buffer_overflow_function(Isolate* isolate) {
return ExternalReference(Redirect(
isolate,
FUNCTION_ADDR(StoreBuffer::StoreBufferOverflow)));
}
ExternalReference ExternalReference::flush_icache_function(Isolate* isolate) {
return ExternalReference(Redirect(isolate, FUNCTION_ADDR(CPU::FlushICache)));
}
ExternalReference ExternalReference::perform_gc_function(Isolate* isolate) {
return
ExternalReference(Redirect(isolate, FUNCTION_ADDR(Runtime::PerformGC)));
}
ExternalReference ExternalReference::delete_handle_scope_extensions(
Isolate* isolate) {
return ExternalReference(Redirect(
isolate,
FUNCTION_ADDR(HandleScope::DeleteExtensions)));
}
ExternalReference ExternalReference::random_uint32_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate, FUNCTION_ADDR(V8::Random)));
}
ExternalReference ExternalReference::get_date_field_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate, FUNCTION_ADDR(JSDate::GetField)));
}
ExternalReference ExternalReference::get_make_code_young_function(
Isolate* isolate) {
return ExternalReference(Redirect(
isolate, FUNCTION_ADDR(Code::MakeCodeAgeSequenceYoung)));
}
ExternalReference ExternalReference::get_mark_code_as_executed_function(
Isolate* isolate) {
return ExternalReference(Redirect(
isolate, FUNCTION_ADDR(Code::MarkCodeAsExecuted)));
}
ExternalReference ExternalReference::date_cache_stamp(Isolate* isolate) {
return ExternalReference(isolate->date_cache()->stamp_address());
}
ExternalReference ExternalReference::stress_deopt_count(Isolate* isolate) {
return ExternalReference(isolate->stress_deopt_count_address());
}
ExternalReference ExternalReference::transcendental_cache_array_address(
Isolate* isolate) {
return ExternalReference(
isolate->transcendental_cache()->cache_array_address());
}
ExternalReference ExternalReference::new_deoptimizer_function(
Isolate* isolate) {
return ExternalReference(
Redirect(isolate, FUNCTION_ADDR(Deoptimizer::New)));
}
ExternalReference ExternalReference::compute_output_frames_function(
Isolate* isolate) {
return ExternalReference(
Redirect(isolate, FUNCTION_ADDR(Deoptimizer::ComputeOutputFrames)));
}
ExternalReference ExternalReference::log_enter_external_function(
Isolate* isolate) {
return ExternalReference(
Redirect(isolate, FUNCTION_ADDR(Logger::EnterExternal)));
}
ExternalReference ExternalReference::log_leave_external_function(
Isolate* isolate) {
return ExternalReference(
Redirect(isolate, FUNCTION_ADDR(Logger::LeaveExternal)));
}
ExternalReference ExternalReference::keyed_lookup_cache_keys(Isolate* isolate) {
return ExternalReference(isolate->keyed_lookup_cache()->keys_address());
}
ExternalReference ExternalReference::keyed_lookup_cache_field_offsets(
Isolate* isolate) {
return ExternalReference(
isolate->keyed_lookup_cache()->field_offsets_address());
}
ExternalReference ExternalReference::roots_array_start(Isolate* isolate) {
return ExternalReference(isolate->heap()->roots_array_start());
}
ExternalReference ExternalReference::allocation_sites_list_address(
Isolate* isolate) {
return ExternalReference(isolate->heap()->allocation_sites_list_address());
}
ExternalReference ExternalReference::address_of_stack_limit(Isolate* isolate) {
return ExternalReference(isolate->stack_guard()->address_of_jslimit());
}
ExternalReference ExternalReference::address_of_real_stack_limit(
Isolate* isolate) {
return ExternalReference(isolate->stack_guard()->address_of_real_jslimit());
}
ExternalReference ExternalReference::address_of_regexp_stack_limit(
Isolate* isolate) {
return ExternalReference(isolate->regexp_stack()->limit_address());
}
ExternalReference ExternalReference::new_space_start(Isolate* isolate) {
return ExternalReference(isolate->heap()->NewSpaceStart());
}
ExternalReference ExternalReference::store_buffer_top(Isolate* isolate) {
return ExternalReference(isolate->heap()->store_buffer()->TopAddress());
}
ExternalReference ExternalReference::new_space_mask(Isolate* isolate) {
return ExternalReference(reinterpret_cast<Address>(
isolate->heap()->NewSpaceMask()));
}
ExternalReference ExternalReference::new_space_allocation_top_address(
Isolate* isolate) {
return ExternalReference(isolate->heap()->NewSpaceAllocationTopAddress());
}
ExternalReference ExternalReference::heap_always_allocate_scope_depth(
Isolate* isolate) {
Heap* heap = isolate->heap();
return ExternalReference(heap->always_allocate_scope_depth_address());
}
ExternalReference ExternalReference::new_space_allocation_limit_address(
Isolate* isolate) {
return ExternalReference(isolate->heap()->NewSpaceAllocationLimitAddress());
}
ExternalReference ExternalReference::old_pointer_space_allocation_top_address(
Isolate* isolate) {
return ExternalReference(
isolate->heap()->OldPointerSpaceAllocationTopAddress());
}
ExternalReference ExternalReference::old_pointer_space_allocation_limit_address(
Isolate* isolate) {
return ExternalReference(
isolate->heap()->OldPointerSpaceAllocationLimitAddress());
}
ExternalReference ExternalReference::old_data_space_allocation_top_address(
Isolate* isolate) {
return ExternalReference(
isolate->heap()->OldDataSpaceAllocationTopAddress());
}
ExternalReference ExternalReference::old_data_space_allocation_limit_address(
Isolate* isolate) {
return ExternalReference(
isolate->heap()->OldDataSpaceAllocationLimitAddress());
}
ExternalReference ExternalReference::
new_space_high_promotion_mode_active_address(Isolate* isolate) {
return ExternalReference(
isolate->heap()->NewSpaceHighPromotionModeActiveAddress());
}
ExternalReference ExternalReference::handle_scope_level_address(
Isolate* isolate) {
return ExternalReference(HandleScope::current_level_address(isolate));
}
ExternalReference ExternalReference::handle_scope_next_address(
Isolate* isolate) {
return ExternalReference(HandleScope::current_next_address(isolate));
}
ExternalReference ExternalReference::handle_scope_limit_address(
Isolate* isolate) {
return ExternalReference(HandleScope::current_limit_address(isolate));
}
ExternalReference ExternalReference::scheduled_exception_address(
Isolate* isolate) {
return ExternalReference(isolate->scheduled_exception_address());
}
ExternalReference ExternalReference::address_of_pending_message_obj(
Isolate* isolate) {
return ExternalReference(isolate->pending_message_obj_address());
}
ExternalReference ExternalReference::address_of_has_pending_message(
Isolate* isolate) {
return ExternalReference(isolate->has_pending_message_address());
}
ExternalReference ExternalReference::address_of_pending_message_script(
Isolate* isolate) {
return ExternalReference(isolate->pending_message_script_address());
}
ExternalReference ExternalReference::address_of_min_int() {
return ExternalReference(reinterpret_cast<void*>(&double_constants.min_int));
}
ExternalReference ExternalReference::address_of_one_half() {
return ExternalReference(reinterpret_cast<void*>(&double_constants.one_half));
}
ExternalReference ExternalReference::address_of_minus_one_half() {
return ExternalReference(
reinterpret_cast<void*>(&double_constants.minus_one_half));
}
ExternalReference ExternalReference::address_of_minus_zero() {
return ExternalReference(
reinterpret_cast<void*>(&double_constants.minus_zero));
}
ExternalReference ExternalReference::address_of_zero() {
return ExternalReference(reinterpret_cast<void*>(&double_constants.zero));
}
ExternalReference ExternalReference::address_of_uint8_max_value() {
return ExternalReference(
reinterpret_cast<void*>(&double_constants.uint8_max_value));
}
ExternalReference ExternalReference::address_of_negative_infinity() {
return ExternalReference(
reinterpret_cast<void*>(&double_constants.negative_infinity));
}
ExternalReference ExternalReference::address_of_canonical_non_hole_nan() {
return ExternalReference(
reinterpret_cast<void*>(&double_constants.canonical_non_hole_nan));
}
ExternalReference ExternalReference::address_of_the_hole_nan() {
return ExternalReference(
reinterpret_cast<void*>(&double_constants.the_hole_nan));
}
ExternalReference ExternalReference::address_of_uint32_bias() {
return ExternalReference(
reinterpret_cast<void*>(&double_constants.uint32_bias));
}
#ifndef V8_INTERPRETED_REGEXP
ExternalReference ExternalReference::re_check_stack_guard_state(
Isolate* isolate) {
Address function;
#if V8_TARGET_ARCH_X64
function = FUNCTION_ADDR(RegExpMacroAssemblerX64::CheckStackGuardState);
#elif V8_TARGET_ARCH_IA32
function = FUNCTION_ADDR(RegExpMacroAssemblerIA32::CheckStackGuardState);
#elif V8_TARGET_ARCH_ARM
function = FUNCTION_ADDR(RegExpMacroAssemblerARM::CheckStackGuardState);
#elif V8_TARGET_ARCH_MIPS
function = FUNCTION_ADDR(RegExpMacroAssemblerMIPS::CheckStackGuardState);
#else
UNREACHABLE();
#endif
return ExternalReference(Redirect(isolate, function));
}
ExternalReference ExternalReference::re_grow_stack(Isolate* isolate) {
return ExternalReference(
Redirect(isolate, FUNCTION_ADDR(NativeRegExpMacroAssembler::GrowStack)));
}
ExternalReference ExternalReference::re_case_insensitive_compare_uc16(
Isolate* isolate) {
return ExternalReference(Redirect(
isolate,
FUNCTION_ADDR(NativeRegExpMacroAssembler::CaseInsensitiveCompareUC16)));
}
ExternalReference ExternalReference::re_word_character_map() {
return ExternalReference(
NativeRegExpMacroAssembler::word_character_map_address());
}
ExternalReference ExternalReference::address_of_static_offsets_vector(
Isolate* isolate) {
return ExternalReference(
reinterpret_cast<Address>(isolate->jsregexp_static_offsets_vector()));
}
ExternalReference ExternalReference::address_of_regexp_stack_memory_address(
Isolate* isolate) {
return ExternalReference(
isolate->regexp_stack()->memory_address());
}
ExternalReference ExternalReference::address_of_regexp_stack_memory_size(
Isolate* isolate) {
return ExternalReference(isolate->regexp_stack()->memory_size_address());
}
#endif // V8_INTERPRETED_REGEXP
static double add_two_doubles(double x, double y) {
return x + y;
}
static double sub_two_doubles(double x, double y) {
return x - y;
}
static double mul_two_doubles(double x, double y) {
return x * y;
}
static double div_two_doubles(double x, double y) {
return x / y;
}
static double mod_two_doubles(double x, double y) {
return modulo(x, y);
}
static double math_sin_double(double x) {
return sin(x);
}
static double math_cos_double(double x) {
return cos(x);
}
static double math_tan_double(double x) {
return tan(x);
}
static double math_log_double(double x) {
return log(x);
}
ExternalReference ExternalReference::math_sin_double_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(math_sin_double),
BUILTIN_FP_CALL));
}
ExternalReference ExternalReference::math_cos_double_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(math_cos_double),
BUILTIN_FP_CALL));
}
ExternalReference ExternalReference::math_tan_double_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(math_tan_double),
BUILTIN_FP_CALL));
}
ExternalReference ExternalReference::math_log_double_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(math_log_double),
BUILTIN_FP_CALL));
}
ExternalReference ExternalReference::math_exp_constants(int constant_index) {
ASSERT(math_exp_data_initialized);
return ExternalReference(
reinterpret_cast<void*>(math_exp_constants_array + constant_index));
}
ExternalReference ExternalReference::math_exp_log_table() {
ASSERT(math_exp_data_initialized);
return ExternalReference(reinterpret_cast<void*>(math_exp_log_table_array));
}
ExternalReference ExternalReference::page_flags(Page* page) {
return ExternalReference(reinterpret_cast<Address>(page) +
MemoryChunk::kFlagsOffset);
}
ExternalReference ExternalReference::ForDeoptEntry(Address entry) {
return ExternalReference(entry);
}
double power_helper(double x, double y) {
int y_int = static_cast<int>(y);
if (y == y_int) {
return power_double_int(x, y_int); // Returns 1 if exponent is 0.
}
if (y == 0.5) {
return (std::isinf(x)) ? V8_INFINITY
: fast_sqrt(x + 0.0); // Convert -0 to +0.
}
if (y == -0.5) {
return (std::isinf(x)) ? 0 : 1.0 / fast_sqrt(x + 0.0); // Convert -0 to +0.
}
return power_double_double(x, y);
}
// Helper function to compute x^y, where y is known to be an
// integer. Uses binary decomposition to limit the number of
// multiplications; see the discussion in "Hacker's Delight" by Henry
// S. Warren, Jr., figure 11-6, page 213.
double power_double_int(double x, int y) {
double m = (y < 0) ? 1 / x : x;
unsigned n = (y < 0) ? -y : y;
double p = 1;
while (n != 0) {
if ((n & 1) != 0) p *= m;
m *= m;
if ((n & 2) != 0) p *= m;
m *= m;
n >>= 2;
}
return p;
}
double power_double_double(double x, double y) {
#if defined(__MINGW64_VERSION_MAJOR) && \
(!defined(__MINGW64_VERSION_RC) || __MINGW64_VERSION_RC < 1)
// MinGW64 has a custom implementation for pow. This handles certain
// special cases that are different.
if ((x == 0.0 || std::isinf(x)) && std::isfinite(y)) {
double f;
if (modf(y, &f) != 0.0) return ((x == 0.0) ^ (y > 0)) ? V8_INFINITY : 0;
}
if (x == 2.0) {
int y_int = static_cast<int>(y);
if (y == y_int) return ldexp(1.0, y_int);
}
#endif
// The checks for special cases can be dropped in ia32 because it has already
// been done in generated code before bailing out here.
if (std::isnan(y) || ((x == 1 || x == -1) && std::isinf(y))) {
return OS::nan_value();
}
return pow(x, y);
}
ExternalReference ExternalReference::power_double_double_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(power_double_double),
BUILTIN_FP_FP_CALL));
}
ExternalReference ExternalReference::power_double_int_function(
Isolate* isolate) {
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(power_double_int),
BUILTIN_FP_INT_CALL));
}
static int native_compare_doubles(double y, double x) {
if (x == y) return EQUAL;
return x < y ? LESS : GREATER;
}
bool EvalComparison(Token::Value op, double op1, double op2) {
ASSERT(Token::IsCompareOp(op));
switch (op) {
case Token::EQ:
case Token::EQ_STRICT: return (op1 == op2);
case Token::NE: return (op1 != op2);
case Token::LT: return (op1 < op2);
case Token::GT: return (op1 > op2);
case Token::LTE: return (op1 <= op2);
case Token::GTE: return (op1 >= op2);
default:
UNREACHABLE();
return false;
}
}
ExternalReference ExternalReference::double_fp_operation(
Token::Value operation, Isolate* isolate) {
typedef double BinaryFPOperation(double x, double y);
BinaryFPOperation* function = NULL;
switch (operation) {
case Token::ADD:
function = &add_two_doubles;
break;
case Token::SUB:
function = &sub_two_doubles;
break;
case Token::MUL:
function = &mul_two_doubles;
break;
case Token::DIV:
function = &div_two_doubles;
break;
case Token::MOD:
function = &mod_two_doubles;
break;
default:
UNREACHABLE();
}
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(function),
BUILTIN_FP_FP_CALL));
}
ExternalReference ExternalReference::compare_doubles(Isolate* isolate) {
return ExternalReference(Redirect(isolate,
FUNCTION_ADDR(native_compare_doubles),
BUILTIN_COMPARE_CALL));
}
#ifdef ENABLE_DEBUGGER_SUPPORT
ExternalReference ExternalReference::debug_break(Isolate* isolate) {
return ExternalReference(Redirect(isolate, FUNCTION_ADDR(Debug_Break)));
}
ExternalReference ExternalReference::debug_step_in_fp_address(
Isolate* isolate) {
return ExternalReference(isolate->debug()->step_in_fp_addr());
}
#endif
void PositionsRecorder::RecordPosition(int pos) {
ASSERT(pos != RelocInfo::kNoPosition);
ASSERT(pos >= 0);
state_.current_position = pos;
#ifdef ENABLE_GDB_JIT_INTERFACE
if (gdbjit_lineinfo_ != NULL) {
gdbjit_lineinfo_->SetPosition(assembler_->pc_offset(), pos, false);
}
#endif
LOG_CODE_EVENT(assembler_->isolate(),
CodeLinePosInfoAddPositionEvent(jit_handler_data_,
assembler_->pc_offset(),
pos));
}
void PositionsRecorder::RecordStatementPosition(int pos) {
ASSERT(pos != RelocInfo::kNoPosition);
ASSERT(pos >= 0);
state_.current_statement_position = pos;
#ifdef ENABLE_GDB_JIT_INTERFACE
if (gdbjit_lineinfo_ != NULL) {
gdbjit_lineinfo_->SetPosition(assembler_->pc_offset(), pos, true);
}
#endif
LOG_CODE_EVENT(assembler_->isolate(),
CodeLinePosInfoAddStatementPositionEvent(
jit_handler_data_,
assembler_->pc_offset(),
pos));
}
bool PositionsRecorder::WriteRecordedPositions() {
bool written = false;
// Write the statement position if it is different from what was written last
// time.
if (state_.current_statement_position != state_.written_statement_position) {
EnsureSpace ensure_space(assembler_);
assembler_->RecordRelocInfo(RelocInfo::STATEMENT_POSITION,
state_.current_statement_position);
state_.written_statement_position = state_.current_statement_position;
written = true;
}
// Write the position if it is different from what was written last time and
// also different from the written statement position.
if (state_.current_position != state_.written_position &&
state_.current_position != state_.written_statement_position) {
EnsureSpace ensure_space(assembler_);
assembler_->RecordRelocInfo(RelocInfo::POSITION, state_.current_position);
state_.written_position = state_.current_position;
written = true;
}
// Return whether something was written.
return written;
}
} } // namespace v8::internal
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