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code-stub-assembler.cc
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// Copyright 2016 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.
#include "src/codegen/code-stub-assembler.h"
#include <stdio.h>
#include <functional>
#include "include/v8-internal.h"
#include "src/base/macros.h"
#include "src/codegen/code-factory.h"
#include "src/codegen/tnode.h"
#include "src/common/globals.h"
#include "src/execution/frames-inl.h"
#include "src/execution/frames.h"
#include "src/execution/protectors.h"
#include "src/heap/heap-inl.h" // For MemoryChunk. TODO(jkummerow): Drop.
#include "src/heap/memory-chunk.h"
#include "src/logging/counters.h"
#include "src/numbers/integer-literal-inl.h"
#include "src/objects/api-callbacks.h"
#include "src/objects/cell.h"
#include "src/objects/descriptor-array.h"
#include "src/objects/function-kind.h"
#include "src/objects/heap-number.h"
#include "src/objects/instance-type-inl.h"
#include "src/objects/instance-type.h"
#include "src/objects/js-generator.h"
#include "src/objects/oddball.h"
#include "src/objects/ordered-hash-table-inl.h"
#include "src/objects/property-cell.h"
#include "src/objects/property-descriptor-object.h"
#include "src/roots/roots.h"
namespace v8 {
namespace internal {
namespace {
Builtin BigIntComparisonBuiltinOf(Operation const& op) {
switch (op) {
case Operation::kLessThan:
return Builtin::kBigIntLessThan;
case Operation::kGreaterThan:
return Builtin::kBigIntGreaterThan;
case Operation::kLessThanOrEqual:
return Builtin::kBigIntLessThanOrEqual;
case Operation::kGreaterThanOrEqual:
return Builtin::kBigIntGreaterThanOrEqual;
default:
UNREACHABLE();
}
}
} // namespace
CodeStubAssembler::CodeStubAssembler(compiler::CodeAssemblerState* state)
: compiler::CodeAssembler(state),
TorqueGeneratedExportedMacrosAssembler(state) {
if (DEBUG_BOOL && v8_flags.csa_trap_on_node != nullptr) {
HandleBreakOnNode();
}
}
void CodeStubAssembler::HandleBreakOnNode() {
// v8_flags.csa_trap_on_node should be in a form "STUB,NODE" where STUB is a
// string specifying the name of a stub and NODE is number specifying node id.
const char* name = state()->name();
size_t name_length = strlen(name);
if (strncmp(v8_flags.csa_trap_on_node, name, name_length) != 0) {
// Different name.
return;
}
size_t option_length = strlen(v8_flags.csa_trap_on_node);
if (option_length < name_length + 2 ||
v8_flags.csa_trap_on_node[name_length] != ',') {
// Option is too short.
return;
}
const char* start = &v8_flags.csa_trap_on_node[name_length + 1];
char* end;
int node_id = static_cast<int>(strtol(start, &end, 10));
if (start == end) {
// Bad node id.
return;
}
BreakOnNode(node_id);
}
void CodeStubAssembler::Dcheck(const BranchGenerator& branch,
const char* message, const char* file, int line,
std::initializer_list<ExtraNode> extra_nodes) {
#if defined(DEBUG)
if (v8_flags.debug_code) {
Check(branch, message, file, line, extra_nodes);
}
#endif
}
void CodeStubAssembler::Dcheck(const NodeGenerator<BoolT>& condition_body,
const char* message, const char* file, int line,
std::initializer_list<ExtraNode> extra_nodes) {
#if defined(DEBUG)
if (v8_flags.debug_code) {
Check(condition_body, message, file, line, extra_nodes);
}
#endif
}
void CodeStubAssembler::Dcheck(TNode<Word32T> condition_node,
const char* message, const char* file, int line,
std::initializer_list<ExtraNode> extra_nodes) {
#if defined(DEBUG)
if (v8_flags.debug_code) {
Check(condition_node, message, file, line, extra_nodes);
}
#endif
}
void CodeStubAssembler::Check(const BranchGenerator& branch,
const char* message, const char* file, int line,
std::initializer_list<ExtraNode> extra_nodes) {
Label ok(this);
Label not_ok(this, Label::kDeferred);
if (message != nullptr) {
Comment("[ Assert: ", message);
} else {
Comment("[ Assert");
}
branch(&ok, ¬_ok);
BIND(¬_ok);
std::vector<FileAndLine> file_and_line;
if (file != nullptr) {
file_and_line.push_back({file, line});
}
FailAssert(message, file_and_line, extra_nodes);
BIND(&ok);
Comment("] Assert");
}
void CodeStubAssembler::Check(const NodeGenerator<BoolT>& condition_body,
const char* message, const char* file, int line,
std::initializer_list<ExtraNode> extra_nodes) {
BranchGenerator branch = [=](Label* ok, Label* not_ok) {
TNode<BoolT> condition = condition_body();
Branch(condition, ok, not_ok);
};
Check(branch, message, file, line, extra_nodes);
}
void CodeStubAssembler::Check(TNode<Word32T> condition_node,
const char* message, const char* file, int line,
std::initializer_list<ExtraNode> extra_nodes) {
BranchGenerator branch = [=](Label* ok, Label* not_ok) {
Branch(condition_node, ok, not_ok);
};
Check(branch, message, file, line, extra_nodes);
}
void CodeStubAssembler::IncrementCallCount(
TNode<FeedbackVector> feedback_vector, TNode<UintPtrT> slot_id) {
Comment("increment call count");
TNode<Smi> call_count =
CAST(LoadFeedbackVectorSlot(feedback_vector, slot_id, kTaggedSize));
// The lowest {FeedbackNexus::CallCountField::kShift} bits of the call
// count are used as flags. To increment the call count by 1 we hence
// have to increment by 1 << {FeedbackNexus::CallCountField::kShift}.
TNode<Smi> new_count = SmiAdd(
call_count, SmiConstant(1 << FeedbackNexus::CallCountField::kShift));
// Count is Smi, so we don't need a write barrier.
StoreFeedbackVectorSlot(feedback_vector, slot_id, new_count,
SKIP_WRITE_BARRIER, kTaggedSize);
}
void CodeStubAssembler::FastCheck(TNode<BoolT> condition) {
Label ok(this), not_ok(this, Label::kDeferred);
Branch(condition, &ok, ¬_ok);
BIND(¬_ok);
Unreachable();
BIND(&ok);
}
void CodeStubAssembler::FailAssert(
const char* message, const std::vector<FileAndLine>& files_and_lines,
std::initializer_list<ExtraNode> extra_nodes) {
DCHECK_NOT_NULL(message);
base::EmbeddedVector<char, 1024> chars;
std::stringstream stream;
for (auto it = files_and_lines.rbegin(); it != files_and_lines.rend(); ++it) {
if (it->first != nullptr) {
stream << " [" << it->first << ":" << it->second << "]";
#ifndef DEBUG
// To limit the size of these strings in release builds, we include only
// the innermost macro's file name and line number.
break;
#endif
}
}
std::string files_and_lines_text = stream.str();
if (files_and_lines_text.size() != 0) {
SNPrintF(chars, "%s%s", message, files_and_lines_text.c_str());
message = chars.begin();
}
TNode<String> message_node = StringConstant(message);
#ifdef DEBUG
// Only print the extra nodes in debug builds.
for (auto& node : extra_nodes) {
CallRuntime(Runtime::kPrintWithNameForAssert, SmiConstant(0),
StringConstant(node.second), node.first);
}
#endif
AbortCSADcheck(message_node);
Unreachable();
}
TNode<Int32T> CodeStubAssembler::SelectInt32Constant(TNode<BoolT> condition,
int true_value,
int false_value) {
return SelectConstant<Int32T>(condition, Int32Constant(true_value),
Int32Constant(false_value));
}
TNode<IntPtrT> CodeStubAssembler::SelectIntPtrConstant(TNode<BoolT> condition,
int true_value,
int false_value) {
return SelectConstant<IntPtrT>(condition, IntPtrConstant(true_value),
IntPtrConstant(false_value));
}
TNode<Oddball> CodeStubAssembler::SelectBooleanConstant(
TNode<BoolT> condition) {
return SelectConstant<Oddball>(condition, TrueConstant(), FalseConstant());
}
TNode<Smi> CodeStubAssembler::SelectSmiConstant(TNode<BoolT> condition,
Smi true_value,
Smi false_value) {
return SelectConstant<Smi>(condition, SmiConstant(true_value),
SmiConstant(false_value));
}
TNode<Smi> CodeStubAssembler::NoContextConstant() {
return SmiConstant(Context::kNoContext);
}
#define HEAP_CONSTANT_ACCESSOR(rootIndexName, rootAccessorName, name) \
TNode<std::remove_pointer<std::remove_reference<decltype( \
std::declval<Heap>().rootAccessorName())>::type>::type> \
CodeStubAssembler::name##Constant() { \
return UncheckedCast<std::remove_pointer<std::remove_reference<decltype( \
std::declval<Heap>().rootAccessorName())>::type>::type>( \
LoadRoot(RootIndex::k##rootIndexName)); \
}
HEAP_MUTABLE_IMMOVABLE_OBJECT_LIST(HEAP_CONSTANT_ACCESSOR)
#undef HEAP_CONSTANT_ACCESSOR
#define HEAP_CONSTANT_ACCESSOR(rootIndexName, rootAccessorName, name) \
TNode<std::remove_pointer<std::remove_reference<decltype( \
std::declval<ReadOnlyRoots>().rootAccessorName())>::type>::type> \
CodeStubAssembler::name##Constant() { \
return UncheckedCast<std::remove_pointer<std::remove_reference<decltype( \
std::declval<ReadOnlyRoots>().rootAccessorName())>::type>::type>( \
LoadRoot(RootIndex::k##rootIndexName)); \
}
HEAP_IMMUTABLE_IMMOVABLE_OBJECT_LIST(HEAP_CONSTANT_ACCESSOR)
#undef HEAP_CONSTANT_ACCESSOR
#define HEAP_CONSTANT_TEST(rootIndexName, rootAccessorName, name) \
TNode<BoolT> CodeStubAssembler::Is##name(TNode<Object> value) { \
return TaggedEqual(value, name##Constant()); \
} \
TNode<BoolT> CodeStubAssembler::IsNot##name(TNode<Object> value) { \
return TaggedNotEqual(value, name##Constant()); \
}
HEAP_IMMOVABLE_OBJECT_LIST(HEAP_CONSTANT_TEST)
#undef HEAP_CONSTANT_TEST
TNode<BInt> CodeStubAssembler::BIntConstant(int value) {
#if defined(BINT_IS_SMI)
return SmiConstant(value);
#elif defined(BINT_IS_INTPTR)
return IntPtrConstant(value);
#else
#error Unknown architecture.
#endif
}
template <>
TNode<Smi> CodeStubAssembler::IntPtrOrSmiConstant<Smi>(int value) {
return SmiConstant(value);
}
template <>
TNode<IntPtrT> CodeStubAssembler::IntPtrOrSmiConstant<IntPtrT>(int value) {
return IntPtrConstant(value);
}
template <>
TNode<UintPtrT> CodeStubAssembler::IntPtrOrSmiConstant<UintPtrT>(int value) {
return Unsigned(IntPtrConstant(value));
}
template <>
TNode<RawPtrT> CodeStubAssembler::IntPtrOrSmiConstant<RawPtrT>(int value) {
return ReinterpretCast<RawPtrT>(IntPtrConstant(value));
}
bool CodeStubAssembler::TryGetIntPtrOrSmiConstantValue(
TNode<Smi> maybe_constant, int* value) {
Smi smi_constant;
if (TryToSmiConstant(maybe_constant, &smi_constant)) {
*value = Smi::ToInt(smi_constant);
return true;
}
return false;
}
bool CodeStubAssembler::TryGetIntPtrOrSmiConstantValue(
TNode<IntPtrT> maybe_constant, int* value) {
int32_t int32_constant;
if (TryToInt32Constant(maybe_constant, &int32_constant)) {
*value = int32_constant;
return true;
}
return false;
}
TNode<IntPtrT> CodeStubAssembler::IntPtrRoundUpToPowerOfTwo32(
TNode<IntPtrT> value) {
Comment("IntPtrRoundUpToPowerOfTwo32");
CSA_DCHECK(this, UintPtrLessThanOrEqual(value, IntPtrConstant(0x80000000u)));
value = Signed(IntPtrSub(value, IntPtrConstant(1)));
for (int i = 1; i <= 16; i *= 2) {
value = Signed(WordOr(value, WordShr(value, IntPtrConstant(i))));
}
return Signed(IntPtrAdd(value, IntPtrConstant(1)));
}
TNode<BoolT> CodeStubAssembler::WordIsPowerOfTwo(TNode<IntPtrT> value) {
intptr_t constant;
if (TryToIntPtrConstant(value, &constant)) {
return BoolConstant(base::bits::IsPowerOfTwo(constant));
}
// value && !(value & (value - 1))
return IntPtrEqual(
Select<IntPtrT>(
IntPtrEqual(value, IntPtrConstant(0)),
[=] { return IntPtrConstant(1); },
[=] { return WordAnd(value, IntPtrSub(value, IntPtrConstant(1))); }),
IntPtrConstant(0));
}
TNode<Float64T> CodeStubAssembler::Float64Round(TNode<Float64T> x) {
TNode<Float64T> one = Float64Constant(1.0);
TNode<Float64T> one_half = Float64Constant(0.5);
Label return_x(this);
// Round up {x} towards Infinity.
TVARIABLE(Float64T, var_x, Float64Ceil(x));
GotoIf(Float64LessThanOrEqual(Float64Sub(var_x.value(), one_half), x),
&return_x);
var_x = Float64Sub(var_x.value(), one);
Goto(&return_x);
BIND(&return_x);
return var_x.value();
}
TNode<Float64T> CodeStubAssembler::Float64Ceil(TNode<Float64T> x) {
TVARIABLE(Float64T, var_x, x);
Label round_op_supported(this), round_op_fallback(this), return_x(this);
// Use UniqueInt32Constant instead of BoolConstant here in order to ensure
// that the graph structure does not depend on the value of the predicate
// (BoolConstant uses cached nodes).
Branch(UniqueInt32Constant(IsFloat64RoundUpSupported()), &round_op_supported,
&round_op_fallback);
BIND(&round_op_supported);
{
// This optional operation is used behind a static check and we rely
// on the dead code elimination to remove this unused unsupported
// instruction. We generate builtins this way in order to ensure that
// builtins PGO profiles are interchangeable between architectures.
var_x = Float64RoundUp(x);
Goto(&return_x);
}
BIND(&round_op_fallback);
{
TNode<Float64T> one = Float64Constant(1.0);
TNode<Float64T> zero = Float64Constant(0.0);
TNode<Float64T> two_52 = Float64Constant(4503599627370496.0E0);
TNode<Float64T> minus_two_52 = Float64Constant(-4503599627370496.0E0);
Label return_minus_x(this);
// Check if {x} is greater than zero.
Label if_xgreaterthanzero(this), if_xnotgreaterthanzero(this);
Branch(Float64GreaterThan(x, zero), &if_xgreaterthanzero,
&if_xnotgreaterthanzero);
BIND(&if_xgreaterthanzero);
{
// Just return {x} unless it's in the range ]0,2^52[.
GotoIf(Float64GreaterThanOrEqual(x, two_52), &return_x);
// Round positive {x} towards Infinity.
var_x = Float64Sub(Float64Add(two_52, x), two_52);
GotoIfNot(Float64LessThan(var_x.value(), x), &return_x);
var_x = Float64Add(var_x.value(), one);
Goto(&return_x);
}
BIND(&if_xnotgreaterthanzero);
{
// Just return {x} unless it's in the range ]-2^52,0[
GotoIf(Float64LessThanOrEqual(x, minus_two_52), &return_x);
GotoIfNot(Float64LessThan(x, zero), &return_x);
// Round negated {x} towards Infinity and return the result negated.
TNode<Float64T> minus_x = Float64Neg(x);
var_x = Float64Sub(Float64Add(two_52, minus_x), two_52);
GotoIfNot(Float64GreaterThan(var_x.value(), minus_x), &return_minus_x);
var_x = Float64Sub(var_x.value(), one);
Goto(&return_minus_x);
}
BIND(&return_minus_x);
var_x = Float64Neg(var_x.value());
Goto(&return_x);
}
BIND(&return_x);
return var_x.value();
}
TNode<Float64T> CodeStubAssembler::Float64Floor(TNode<Float64T> x) {
TVARIABLE(Float64T, var_x, x);
Label round_op_supported(this), round_op_fallback(this), return_x(this);
// Use UniqueInt32Constant instead of BoolConstant here in order to ensure
// that the graph structure does not depend on the value of the predicate
// (BoolConstant uses cached nodes).
Branch(UniqueInt32Constant(IsFloat64RoundDownSupported()),
&round_op_supported, &round_op_fallback);
BIND(&round_op_supported);
{
// This optional operation is used behind a static check and we rely
// on the dead code elimination to remove this unused unsupported
// instruction. We generate builtins this way in order to ensure that
// builtins PGO profiles are interchangeable between architectures.
var_x = Float64RoundDown(x);
Goto(&return_x);
}
BIND(&round_op_fallback);
{
TNode<Float64T> one = Float64Constant(1.0);
TNode<Float64T> zero = Float64Constant(0.0);
TNode<Float64T> two_52 = Float64Constant(4503599627370496.0E0);
TNode<Float64T> minus_two_52 = Float64Constant(-4503599627370496.0E0);
Label return_minus_x(this);
// Check if {x} is greater than zero.
Label if_xgreaterthanzero(this), if_xnotgreaterthanzero(this);
Branch(Float64GreaterThan(x, zero), &if_xgreaterthanzero,
&if_xnotgreaterthanzero);
BIND(&if_xgreaterthanzero);
{
// Just return {x} unless it's in the range ]0,2^52[.
GotoIf(Float64GreaterThanOrEqual(x, two_52), &return_x);
// Round positive {x} towards -Infinity.
var_x = Float64Sub(Float64Add(two_52, x), two_52);
GotoIfNot(Float64GreaterThan(var_x.value(), x), &return_x);
var_x = Float64Sub(var_x.value(), one);
Goto(&return_x);
}
BIND(&if_xnotgreaterthanzero);
{
// Just return {x} unless it's in the range ]-2^52,0[
GotoIf(Float64LessThanOrEqual(x, minus_two_52), &return_x);
GotoIfNot(Float64LessThan(x, zero), &return_x);
// Round negated {x} towards -Infinity and return the result negated.
TNode<Float64T> minus_x = Float64Neg(x);
var_x = Float64Sub(Float64Add(two_52, minus_x), two_52);
GotoIfNot(Float64LessThan(var_x.value(), minus_x), &return_minus_x);
var_x = Float64Add(var_x.value(), one);
Goto(&return_minus_x);
}
BIND(&return_minus_x);
var_x = Float64Neg(var_x.value());
Goto(&return_x);
}
BIND(&return_x);
return var_x.value();
}
TNode<Float64T> CodeStubAssembler::Float64RoundToEven(TNode<Float64T> x) {
TVARIABLE(Float64T, var_result);
Label round_op_supported(this), round_op_fallback(this), done(this);
// Use UniqueInt32Constant instead of BoolConstant here in order to ensure
// that the graph structure does not depend on the value of the predicate
// (BoolConstant uses cached nodes).
Branch(UniqueInt32Constant(IsFloat64RoundTiesEvenSupported()),
&round_op_supported, &round_op_fallback);
BIND(&round_op_supported);
{
// This optional operation is used behind a static check and we rely
// on the dead code elimination to remove this unused unsupported
// instruction. We generate builtins this way in order to ensure that
// builtins PGO profiles are interchangeable between architectures.
var_result = Float64RoundTiesEven(x);
Goto(&done);
}
BIND(&round_op_fallback);
{
// See ES#sec-touint8clamp for details.
TNode<Float64T> f = Float64Floor(x);
TNode<Float64T> f_and_half = Float64Add(f, Float64Constant(0.5));
Label return_f(this), return_f_plus_one(this);
GotoIf(Float64LessThan(f_and_half, x), &return_f_plus_one);
GotoIf(Float64LessThan(x, f_and_half), &return_f);
{
TNode<Float64T> f_mod_2 = Float64Mod(f, Float64Constant(2.0));
Branch(Float64Equal(f_mod_2, Float64Constant(0.0)), &return_f,
&return_f_plus_one);
}
BIND(&return_f);
var_result = f;
Goto(&done);
BIND(&return_f_plus_one);
var_result = Float64Add(f, Float64Constant(1.0));
Goto(&done);
}
BIND(&done);
return var_result.value();
}
TNode<Float64T> CodeStubAssembler::Float64Trunc(TNode<Float64T> x) {
TVARIABLE(Float64T, var_x, x);
Label trunc_op_supported(this), trunc_op_fallback(this), return_x(this);
// Use UniqueInt32Constant instead of BoolConstant here in order to ensure
// that the graph structure does not depend on the value of the predicate
// (BoolConstant uses cached nodes).
Branch(UniqueInt32Constant(IsFloat64RoundTruncateSupported()),
&trunc_op_supported, &trunc_op_fallback);
BIND(&trunc_op_supported);
{
// This optional operation is used behind a static check and we rely
// on the dead code elimination to remove this unused unsupported
// instruction. We generate builtins this way in order to ensure that
// builtins PGO profiles are interchangeable between architectures.
var_x = Float64RoundTruncate(x);
Goto(&return_x);
}
BIND(&trunc_op_fallback);
{
TNode<Float64T> one = Float64Constant(1.0);
TNode<Float64T> zero = Float64Constant(0.0);
TNode<Float64T> two_52 = Float64Constant(4503599627370496.0E0);
TNode<Float64T> minus_two_52 = Float64Constant(-4503599627370496.0E0);
Label return_minus_x(this);
// Check if {x} is greater than 0.
Label if_xgreaterthanzero(this), if_xnotgreaterthanzero(this);
Branch(Float64GreaterThan(x, zero), &if_xgreaterthanzero,
&if_xnotgreaterthanzero);
BIND(&if_xgreaterthanzero);
{
Label round_op_supported(this), round_op_fallback(this);
Branch(UniqueInt32Constant(IsFloat64RoundDownSupported()),
&round_op_supported, &round_op_fallback);
BIND(&round_op_supported);
{
// This optional operation is used behind a static check and we rely
// on the dead code elimination to remove this unused unsupported
// instruction. We generate builtins this way in order to ensure that
// builtins PGO profiles are interchangeable between architectures.
var_x = Float64RoundDown(x);
Goto(&return_x);
}
BIND(&round_op_fallback);
{
// Just return {x} unless it's in the range ]0,2^52[.
GotoIf(Float64GreaterThanOrEqual(x, two_52), &return_x);
// Round positive {x} towards -Infinity.
var_x = Float64Sub(Float64Add(two_52, x), two_52);
GotoIfNot(Float64GreaterThan(var_x.value(), x), &return_x);
var_x = Float64Sub(var_x.value(), one);
Goto(&return_x);
}
}
BIND(&if_xnotgreaterthanzero);
{
Label round_op_supported(this), round_op_fallback(this);
Branch(UniqueInt32Constant(IsFloat64RoundUpSupported()),
&round_op_supported, &round_op_fallback);
BIND(&round_op_supported);
{
// This optional operation is used behind a static check and we rely
// on the dead code elimination to remove this unused unsupported
// instruction. We generate builtins this way in order to ensure that
// builtins PGO profiles are interchangeable between architectures.
var_x = Float64RoundUp(x);
Goto(&return_x);
}
BIND(&round_op_fallback);
{
// Just return {x} unless its in the range ]-2^52,0[.
GotoIf(Float64LessThanOrEqual(x, minus_two_52), &return_x);
GotoIfNot(Float64LessThan(x, zero), &return_x);
// Round negated {x} towards -Infinity and return result negated.
TNode<Float64T> minus_x = Float64Neg(x);
var_x = Float64Sub(Float64Add(two_52, minus_x), two_52);
GotoIfNot(Float64GreaterThan(var_x.value(), minus_x), &return_minus_x);
var_x = Float64Sub(var_x.value(), one);
Goto(&return_minus_x);
}
}
BIND(&return_minus_x);
var_x = Float64Neg(var_x.value());
Goto(&return_x);
}
BIND(&return_x);
return var_x.value();
}
TNode<IntPtrT> CodeStubAssembler::PopulationCountFallback(
TNode<UintPtrT> value) {
// Taken from slow path of base::bits::CountPopulation, the comments here show
// C++ code and comments from there for reference.
// Fall back to divide-and-conquer popcount (see "Hacker's Delight" by Henry
// S. Warren, Jr.), chapter 5-1.
constexpr uintptr_t mask[] = {static_cast<uintptr_t>(0x5555555555555555),
static_cast<uintptr_t>(0x3333333333333333),
static_cast<uintptr_t>(0x0f0f0f0f0f0f0f0f)};
// TNode<UintPtrT> value = Unsigned(value_word);
TNode<UintPtrT> lhs, rhs;
// Start with 64 buckets of 1 bits, holding values from [0,1].
// {value = ((value >> 1) & mask[0]) + (value & mask[0])}
lhs = WordAnd(WordShr(value, UintPtrConstant(1)), UintPtrConstant(mask[0]));
rhs = WordAnd(value, UintPtrConstant(mask[0]));
value = UintPtrAdd(lhs, rhs);
// Having 32 buckets of 2 bits, holding values from [0,2] now.
// {value = ((value >> 2) & mask[1]) + (value & mask[1])}
lhs = WordAnd(WordShr(value, UintPtrConstant(2)), UintPtrConstant(mask[1]));
rhs = WordAnd(value, UintPtrConstant(mask[1]));
value = UintPtrAdd(lhs, rhs);
// Having 16 buckets of 4 bits, holding values from [0,4] now.
// {value = ((value >> 4) & mask[2]) + (value & mask[2])}
lhs = WordAnd(WordShr(value, UintPtrConstant(4)), UintPtrConstant(mask[2]));
rhs = WordAnd(value, UintPtrConstant(mask[2]));
value = UintPtrAdd(lhs, rhs);
// Having 8 buckets of 8 bits, holding values from [0,8] now.
// From this point on, the buckets are bigger than the number of bits
// required to hold the values, and the buckets are bigger the maximum
// result, so there's no need to mask value anymore, since there's no
// more risk of overflow between buckets.
// {value = (value >> 8) + value}
lhs = WordShr(value, UintPtrConstant(8));
value = UintPtrAdd(lhs, value);
// Having 4 buckets of 16 bits, holding values from [0,16] now.
// {value = (value >> 16) + value}
lhs = WordShr(value, UintPtrConstant(16));
value = UintPtrAdd(lhs, value);
if (Is64()) {
// Having 2 buckets of 32 bits, holding values from [0,32] now.
// {value = (value >> 32) + value}
lhs = WordShr(value, UintPtrConstant(32));
value = UintPtrAdd(lhs, value);
}
// Having 1 buckets of sizeof(intptr_t) bits, holding values from [0,64] now.
// {return static_cast<unsigned>(value & 0xff)}
return Signed(WordAnd(value, UintPtrConstant(0xff)));
}
TNode<Int64T> CodeStubAssembler::PopulationCount64(TNode<Word64T> value) {
if (IsWord64PopcntSupported()) {
return Word64Popcnt(value);
}
if (Is32()) {
// Unsupported.
UNREACHABLE();
}
return ReinterpretCast<Int64T>(
PopulationCountFallback(ReinterpretCast<UintPtrT>(value)));
}
TNode<Int32T> CodeStubAssembler::PopulationCount32(TNode<Word32T> value) {
if (IsWord32PopcntSupported()) {
return Word32Popcnt(value);
}
if (Is32()) {
TNode<IntPtrT> res =
PopulationCountFallback(ReinterpretCast<UintPtrT>(value));
return ReinterpretCast<Int32T>(res);
} else {
TNode<IntPtrT> res = PopulationCountFallback(
ReinterpretCast<UintPtrT>(ChangeUint32ToUint64(value)));
return TruncateInt64ToInt32(ReinterpretCast<Int64T>(res));
}
}
TNode<Int64T> CodeStubAssembler::CountTrailingZeros64(TNode<Word64T> value) {
if (IsWord64CtzSupported()) {
return Word64Ctz(value);
}
if (Is32()) {
// Unsupported.
UNREACHABLE();
}
// Same fallback as in base::bits::CountTrailingZeros.
// Fall back to popcount (see "Hacker's Delight" by Henry S. Warren, Jr.),
// chapter 5-4. On x64, since is faster than counting in a loop and faster
// than doing binary search.
TNode<Word64T> lhs = Word64Not(value);
TNode<Word64T> rhs = Uint64Sub(Unsigned(value), Uint64Constant(1));
return PopulationCount64(Word64And(lhs, rhs));
}
TNode<Int32T> CodeStubAssembler::CountTrailingZeros32(TNode<Word32T> value) {
if (IsWord32CtzSupported()) {
return Word32Ctz(value);
}
if (Is32()) {
// Same fallback as in Word64CountTrailingZeros.
TNode<Word32T> lhs = Word32BitwiseNot(value);
TNode<Word32T> rhs = Int32Sub(Signed(value), Int32Constant(1));
return PopulationCount32(Word32And(lhs, rhs));
} else {
TNode<Int64T> res64 = CountTrailingZeros64(ChangeUint32ToUint64(value));
return TruncateInt64ToInt32(Signed(res64));
}
}
TNode<Int64T> CodeStubAssembler::CountLeadingZeros64(TNode<Word64T> value) {
return Word64Clz(value);
}
TNode<Int32T> CodeStubAssembler::CountLeadingZeros32(TNode<Word32T> value) {
return Word32Clz(value);
}
template <>
TNode<Smi> CodeStubAssembler::TaggedToParameter(TNode<Smi> value) {
return value;
}
template <>
TNode<IntPtrT> CodeStubAssembler::TaggedToParameter(TNode<Smi> value) {
return SmiUntag(value);
}
TNode<IntPtrT> CodeStubAssembler::TaggedIndexToIntPtr(
TNode<TaggedIndex> value) {
return Signed(WordSarShiftOutZeros(BitcastTaggedToWordForTagAndSmiBits(value),
IntPtrConstant(kSmiTagSize)));
}
TNode<TaggedIndex> CodeStubAssembler::IntPtrToTaggedIndex(
TNode<IntPtrT> value) {
return ReinterpretCast<TaggedIndex>(
BitcastWordToTaggedSigned(WordShl(value, IntPtrConstant(kSmiTagSize))));
}
TNode<Smi> CodeStubAssembler::TaggedIndexToSmi(TNode<TaggedIndex> value) {
if (SmiValuesAre32Bits()) {
DCHECK_EQ(kSmiShiftSize, 31);
return BitcastWordToTaggedSigned(
WordShl(BitcastTaggedToWordForTagAndSmiBits(value),
IntPtrConstant(kSmiShiftSize)));
}
DCHECK(SmiValuesAre31Bits());
DCHECK_EQ(kSmiShiftSize, 0);
return ReinterpretCast<Smi>(value);
}
TNode<TaggedIndex> CodeStubAssembler::SmiToTaggedIndex(TNode<Smi> value) {
if (kSystemPointerSize == kInt32Size) {
return ReinterpretCast<TaggedIndex>(value);
}
if (SmiValuesAre32Bits()) {
DCHECK_EQ(kSmiShiftSize, 31);
return ReinterpretCast<TaggedIndex>(BitcastWordToTaggedSigned(
WordSar(BitcastTaggedToWordForTagAndSmiBits(value),
IntPtrConstant(kSmiShiftSize))));
}
DCHECK(SmiValuesAre31Bits());
DCHECK_EQ(kSmiShiftSize, 0);
// Just sign-extend the lower 32 bits.
TNode<Int32T> raw =
TruncateWordToInt32(BitcastTaggedToWordForTagAndSmiBits(value));
return ReinterpretCast<TaggedIndex>(
BitcastWordToTaggedSigned(ChangeInt32ToIntPtr(raw)));
}
TNode<Smi> CodeStubAssembler::NormalizeSmiIndex(TNode<Smi> smi_index) {
if (COMPRESS_POINTERS_BOOL) {
TNode<Int32T> raw =
TruncateWordToInt32(BitcastTaggedToWordForTagAndSmiBits(smi_index));
smi_index = BitcastWordToTaggedSigned(ChangeInt32ToIntPtr(raw));
}
return smi_index;
}
TNode<Smi> CodeStubAssembler::SmiFromInt32(TNode<Int32T> value) {
if (COMPRESS_POINTERS_BOOL) {
static_assert(!COMPRESS_POINTERS_BOOL || (kSmiShiftSize + kSmiTagSize == 1),
"Use shifting instead of add");
return BitcastWordToTaggedSigned(
ChangeUint32ToWord(Int32Add(value, value)));
}
return SmiTag(ChangeInt32ToIntPtr(value));
}
TNode<Smi> CodeStubAssembler::SmiFromUint32(TNode<Uint32T> value) {
CSA_DCHECK(this, IntPtrLessThan(ChangeUint32ToWord(value),
IntPtrConstant(Smi::kMaxValue)));
return SmiFromInt32(Signed(value));
}
TNode<BoolT> CodeStubAssembler::IsValidPositiveSmi(TNode<IntPtrT> value) {
intptr_t constant_value;
if (TryToIntPtrConstant(value, &constant_value)) {
return (static_cast<uintptr_t>(constant_value) <=
static_cast<uintptr_t>(Smi::kMaxValue))
? Int32TrueConstant()
: Int32FalseConstant();
}
return UintPtrLessThanOrEqual(value, IntPtrConstant(Smi::kMaxValue));
}
TNode<Smi> CodeStubAssembler::SmiTag(TNode<IntPtrT> value) {
int32_t constant_value;
if (TryToInt32Constant(value, &constant_value) &&
Smi::IsValid(constant_value)) {
return SmiConstant(constant_value);
}
if (COMPRESS_POINTERS_BOOL) {
return SmiFromInt32(TruncateIntPtrToInt32(value));
}
TNode<Smi> smi =
BitcastWordToTaggedSigned(WordShl(value, SmiShiftBitsConstant()));
return smi;
}
TNode<IntPtrT> CodeStubAssembler::SmiUntag(TNode<Smi> value) {
intptr_t constant_value;
if (TryToIntPtrConstant(value, &constant_value)) {
return IntPtrConstant(constant_value >> (kSmiShiftSize + kSmiTagSize));
}
TNode<IntPtrT> raw_bits = BitcastTaggedToWordForTagAndSmiBits(value);
if (COMPRESS_POINTERS_BOOL) {
// Clear the upper half using sign-extension.
raw_bits = ChangeInt32ToIntPtr(TruncateIntPtrToInt32(raw_bits));
}
return Signed(WordSarShiftOutZeros(raw_bits, SmiShiftBitsConstant()));
}
TNode<Int32T> CodeStubAssembler::SmiToInt32(TNode<Smi> value) {
if (COMPRESS_POINTERS_BOOL) {
return Signed(Word32SarShiftOutZeros(
TruncateIntPtrToInt32(BitcastTaggedToWordForTagAndSmiBits(value)),
SmiShiftBitsConstant32()));
}
TNode<IntPtrT> result = SmiUntag(value);
return TruncateIntPtrToInt32(result);
}
TNode<Float64T> CodeStubAssembler::SmiToFloat64(TNode<Smi> value) {
return ChangeInt32ToFloat64(SmiToInt32(value));
}
TNode<Smi> CodeStubAssembler::SmiMax(TNode<Smi> a, TNode<Smi> b) {
return SelectConstant<Smi>(SmiLessThan(a, b), b, a);
}
TNode<Smi> CodeStubAssembler::SmiMin(TNode<Smi> a, TNode<Smi> b) {
return SelectConstant<Smi>(SmiLessThan(a, b), a, b);
}
TNode<IntPtrT> CodeStubAssembler::TryIntPtrAdd(TNode<IntPtrT> a,
TNode<IntPtrT> b,
Label* if_overflow) {
TNode<PairT<IntPtrT, BoolT>> pair = IntPtrAddWithOverflow(a, b);
TNode<BoolT> overflow = Projection<1>(pair);
GotoIf(overflow, if_overflow);
return Projection<0>(pair);
}
TNode<IntPtrT> CodeStubAssembler::TryIntPtrSub(TNode<IntPtrT> a,
TNode<IntPtrT> b,
Label* if_overflow) {
TNode<PairT<IntPtrT, BoolT>> pair = IntPtrSubWithOverflow(a, b);
TNode<BoolT> overflow = Projection<1>(pair);
GotoIf(overflow, if_overflow);
return Projection<0>(pair);
}
TNode<IntPtrT> CodeStubAssembler::TryIntPtrMul(TNode<IntPtrT> a,
TNode<IntPtrT> b,
Label* if_overflow) {
TNode<PairT<IntPtrT, BoolT>> pair = IntPtrMulWithOverflow(a, b);
TNode<BoolT> overflow = Projection<1>(pair);
GotoIf(overflow, if_overflow);
return Projection<0>(pair);
}
TNode<IntPtrT> CodeStubAssembler::TryIntPtrDiv(TNode<IntPtrT> a,
TNode<IntPtrT> b,
Label* if_div_zero) {
GotoIf(IntPtrEqual(b, IntPtrConstant(0)), if_div_zero);
return IntPtrDiv(a, b);
}
TNode<IntPtrT> CodeStubAssembler::TryIntPtrMod(TNode<IntPtrT> a,
TNode<IntPtrT> b,
Label* if_div_zero) {
GotoIf(IntPtrEqual(b, IntPtrConstant(0)), if_div_zero);
return IntPtrMod(a, b);
}
TNode<Int32T> CodeStubAssembler::TryInt32Mul(TNode<Int32T> a, TNode<Int32T> b,
Label* if_overflow) {
TNode<PairT<Int32T, BoolT>> pair = Int32MulWithOverflow(a, b);
TNode<BoolT> overflow = Projection<1>(pair);
GotoIf(overflow, if_overflow);
return Projection<0>(pair);
}
TNode<Smi> CodeStubAssembler::TrySmiAdd(TNode<Smi> lhs, TNode<Smi> rhs,
Label* if_overflow) {
if (SmiValuesAre32Bits()) {
return BitcastWordToTaggedSigned(
TryIntPtrAdd(BitcastTaggedToWordForTagAndSmiBits(lhs),
BitcastTaggedToWordForTagAndSmiBits(rhs), if_overflow));
} else {
DCHECK(SmiValuesAre31Bits());
TNode<PairT<Int32T, BoolT>> pair = Int32AddWithOverflow(
TruncateIntPtrToInt32(BitcastTaggedToWordForTagAndSmiBits(lhs)),
TruncateIntPtrToInt32(BitcastTaggedToWordForTagAndSmiBits(rhs)));
TNode<BoolT> overflow = Projection<1>(pair);
GotoIf(overflow, if_overflow);
TNode<Int32T> result = Projection<0>(pair);
return BitcastWordToTaggedSigned(ChangeInt32ToIntPtr(result));
}
}
TNode<Smi> CodeStubAssembler::TrySmiSub(TNode<Smi> lhs, TNode<Smi> rhs,
Label* if_overflow) {
if (SmiValuesAre32Bits()) {
TNode<PairT<IntPtrT, BoolT>> pair =
IntPtrSubWithOverflow(BitcastTaggedToWordForTagAndSmiBits(lhs),
BitcastTaggedToWordForTagAndSmiBits(rhs));
TNode<BoolT> overflow = Projection<1>(pair);
GotoIf(overflow, if_overflow);