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cobalt / cobalt / 2a8c847d785c1602f60915c8e0112e0aec6a15a5 / . / src / v8 / src / builtins / builtins-string-gen.cc
blob: 195572de8ed0f38cea7776f62437fcc25ce077ad [file] [log] [blame]
// Copyright 2017 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/builtins/builtins-string-gen.h"
#include "src/builtins/builtins-regexp-gen.h"
#include "src/builtins/builtins-utils-gen.h"
#include "src/builtins/builtins.h"
#include "src/code-factory.h"
#include "src/factory-inl.h"
#include "src/objects.h"
namespace v8 {
namespace internal {
typedef compiler::Node Node;
template <class T>
using TNode = compiler::TNode<T>;
Node* StringBuiltinsAssembler::DirectStringData(Node* string,
Node* string_instance_type) {
// Compute the effective offset of the first character.
VARIABLE(var_data, MachineType::PointerRepresentation());
Label if_sequential(this), if_external(this), if_join(this);
Branch(Word32Equal(Word32And(string_instance_type,
Int32Constant(kStringRepresentationMask)),
Int32Constant(kSeqStringTag)),
&if_sequential, &if_external);
BIND(&if_sequential);
{
var_data.Bind(IntPtrAdd(
IntPtrConstant(SeqOneByteString::kHeaderSize - kHeapObjectTag),
BitcastTaggedToWord(string)));
Goto(&if_join);
}
BIND(&if_external);
{
// This is only valid for ExternalStrings where the resource data
// pointer is cached (i.e. no short external strings).
CSA_ASSERT(
this, Word32NotEqual(Word32And(string_instance_type,
Int32Constant(kShortExternalStringMask)),
Int32Constant(kShortExternalStringTag)));
var_data.Bind(LoadObjectField(string, ExternalString::kResourceDataOffset,
MachineType::Pointer()));
Goto(&if_join);
}
BIND(&if_join);
return var_data.value();
}
void StringBuiltinsAssembler::DispatchOnStringEncodings(
Node* const lhs_instance_type, Node* const rhs_instance_type,
Label* if_one_one, Label* if_one_two, Label* if_two_one,
Label* if_two_two) {
STATIC_ASSERT(kStringEncodingMask == 0x8);
STATIC_ASSERT(kTwoByteStringTag == 0x0);
STATIC_ASSERT(kOneByteStringTag == 0x8);
// First combine the encodings.
Node* const encoding_mask = Int32Constant(kStringEncodingMask);
Node* const lhs_encoding = Word32And(lhs_instance_type, encoding_mask);
Node* const rhs_encoding = Word32And(rhs_instance_type, encoding_mask);
Node* const combined_encodings =
Word32Or(lhs_encoding, Word32Shr(rhs_encoding, 1));
// Then dispatch on the combined encoding.
Label unreachable(this, Label::kDeferred);
int32_t values[] = {
kOneByteStringTag | (kOneByteStringTag >> 1),
kOneByteStringTag | (kTwoByteStringTag >> 1),
kTwoByteStringTag | (kOneByteStringTag >> 1),
kTwoByteStringTag | (kTwoByteStringTag >> 1),
};
Label* labels[] = {
if_one_one, if_one_two, if_two_one, if_two_two,
};
STATIC_ASSERT(arraysize(values) == arraysize(labels));
Switch(combined_encodings, &unreachable, values, labels, arraysize(values));
BIND(&unreachable);
Unreachable();
}
template <typename SubjectChar, typename PatternChar>
Node* StringBuiltinsAssembler::CallSearchStringRaw(Node* const subject_ptr,
Node* const subject_length,
Node* const search_ptr,
Node* const search_length,
Node* const start_position) {
Node* const function_addr = ExternalConstant(
ExternalReference::search_string_raw<SubjectChar, PatternChar>(
isolate()));
Node* const isolate_ptr =
ExternalConstant(ExternalReference::isolate_address(isolate()));
MachineType type_ptr = MachineType::Pointer();
MachineType type_intptr = MachineType::IntPtr();
Node* const result = CallCFunction6(
type_intptr, type_ptr, type_ptr, type_intptr, type_ptr, type_intptr,
type_intptr, function_addr, isolate_ptr, subject_ptr, subject_length,
search_ptr, search_length, start_position);
return result;
}
Node* StringBuiltinsAssembler::PointerToStringDataAtIndex(
Node* const string_data, Node* const index, String::Encoding encoding) {
const ElementsKind kind = (encoding == String::ONE_BYTE_ENCODING)
? UINT8_ELEMENTS
: UINT16_ELEMENTS;
Node* const offset_in_bytes =
ElementOffsetFromIndex(index, kind, INTPTR_PARAMETERS);
return IntPtrAdd(string_data, offset_in_bytes);
}
void StringBuiltinsAssembler::ConvertAndBoundsCheckStartArgument(
Node* context, Variable* var_start, Node* start, Node* string_length) {
TNode<Object> const start_int = ToInteger_Inline(
CAST(context), CAST(start), CodeStubAssembler::kTruncateMinusZero);
TNode<Smi> const zero = SmiConstant(0);
Label done(this);
Label if_issmi(this), if_isheapnumber(this, Label::kDeferred);
Branch(TaggedIsSmi(start_int), &if_issmi, &if_isheapnumber);
BIND(&if_issmi);
{
TNode<Smi> const start_int_smi = CAST(start_int);
var_start->Bind(Select(
SmiLessThan(start_int_smi, zero),
[&] { return SmiMax(SmiAdd(string_length, start_int_smi), zero); },
[&] { return start_int_smi; }, MachineRepresentation::kTagged));
Goto(&done);
}
BIND(&if_isheapnumber);
{
// If {start} is a heap number, it is definitely out of bounds. If it is
// negative, {start} = max({string_length} + {start}),0) = 0'. If it is
// positive, set {start} to {string_length} which ultimately results in
// returning an empty string.
TNode<HeapNumber> const start_int_hn = CAST(start_int);
TNode<Float64T> const float_zero = Float64Constant(0.);
TNode<Float64T> const start_float = LoadHeapNumberValue(start_int_hn);
var_start->Bind(SelectTaggedConstant<Smi>(
Float64LessThan(start_float, float_zero), zero, string_length));
Goto(&done);
}
BIND(&done);
}
void StringBuiltinsAssembler::GenerateStringEqual(Node* context, Node* left,
Node* right) {
VARIABLE(var_left, MachineRepresentation::kTagged, left);
VARIABLE(var_right, MachineRepresentation::kTagged, right);
Label if_equal(this), if_notequal(this), if_indirect(this, Label::kDeferred),
restart(this, {&var_left, &var_right});
TNode<IntPtrT> lhs_length = LoadStringLengthAsWord(left);
TNode<IntPtrT> rhs_length = LoadStringLengthAsWord(right);
// Strings with different lengths cannot be equal.
GotoIf(WordNotEqual(lhs_length, rhs_length), &if_notequal);
Goto(&restart);
BIND(&restart);
Node* lhs = var_left.value();
Node* rhs = var_right.value();
Node* lhs_instance_type = LoadInstanceType(lhs);
Node* rhs_instance_type = LoadInstanceType(rhs);
StringEqual_Core(context, lhs, lhs_instance_type, rhs, rhs_instance_type,
lhs_length, &if_equal, &if_notequal, &if_indirect);
BIND(&if_indirect);
{
// Try to unwrap indirect strings, restart the above attempt on success.
MaybeDerefIndirectStrings(&var_left, lhs_instance_type, &var_right,
rhs_instance_type, &restart);
TailCallRuntime(Runtime::kStringEqual, context, lhs, rhs);
}
BIND(&if_equal);
Return(TrueConstant());
BIND(&if_notequal);
Return(FalseConstant());
}
void StringBuiltinsAssembler::StringEqual_Core(
Node* context, Node* lhs, Node* lhs_instance_type, Node* rhs,
Node* rhs_instance_type, TNode<IntPtrT> length, Label* if_equal,
Label* if_not_equal, Label* if_indirect) {
CSA_ASSERT(this, IsString(lhs));
CSA_ASSERT(this, IsString(rhs));
CSA_ASSERT(this, WordEqual(LoadStringLengthAsWord(lhs), length));
CSA_ASSERT(this, WordEqual(LoadStringLengthAsWord(rhs), length));
// Fast check to see if {lhs} and {rhs} refer to the same String object.
GotoIf(WordEqual(lhs, rhs), if_equal);
// Combine the instance types into a single 16-bit value, so we can check
// both of them at once.
Node* both_instance_types = Word32Or(
lhs_instance_type, Word32Shl(rhs_instance_type, Int32Constant(8)));
// Check if both {lhs} and {rhs} are internalized. Since we already know
// that they're not the same object, they're not equal in that case.
int const kBothInternalizedMask =
kIsNotInternalizedMask | (kIsNotInternalizedMask << 8);
int const kBothInternalizedTag = kInternalizedTag | (kInternalizedTag << 8);
GotoIf(Word32Equal(Word32And(both_instance_types,
Int32Constant(kBothInternalizedMask)),
Int32Constant(kBothInternalizedTag)),
if_not_equal);
// Check if both {lhs} and {rhs} are direct strings, and that in case of
// ExternalStrings the data pointer is cached.
STATIC_ASSERT(kShortExternalStringTag != 0);
STATIC_ASSERT(kIsIndirectStringTag != 0);
int const kBothDirectStringMask =
kIsIndirectStringMask | kShortExternalStringMask |
((kIsIndirectStringMask | kShortExternalStringMask) << 8);
GotoIfNot(Word32Equal(Word32And(both_instance_types,
Int32Constant(kBothDirectStringMask)),
Int32Constant(0)),
if_indirect);
// Dispatch based on the {lhs} and {rhs} string encoding.
int const kBothStringEncodingMask =
kStringEncodingMask | (kStringEncodingMask << 8);
int const kOneOneByteStringTag = kOneByteStringTag | (kOneByteStringTag << 8);
int const kTwoTwoByteStringTag = kTwoByteStringTag | (kTwoByteStringTag << 8);
int const kOneTwoByteStringTag = kOneByteStringTag | (kTwoByteStringTag << 8);
Label if_oneonebytestring(this), if_twotwobytestring(this),
if_onetwobytestring(this), if_twoonebytestring(this);
Node* masked_instance_types =
Word32And(both_instance_types, Int32Constant(kBothStringEncodingMask));
GotoIf(
Word32Equal(masked_instance_types, Int32Constant(kOneOneByteStringTag)),
&if_oneonebytestring);
GotoIf(
Word32Equal(masked_instance_types, Int32Constant(kTwoTwoByteStringTag)),
&if_twotwobytestring);
Branch(
Word32Equal(masked_instance_types, Int32Constant(kOneTwoByteStringTag)),
&if_onetwobytestring, &if_twoonebytestring);
BIND(&if_oneonebytestring);
StringEqual_Loop(lhs, lhs_instance_type, MachineType::Uint8(), rhs,
rhs_instance_type, MachineType::Uint8(), length, if_equal,
if_not_equal);
BIND(&if_twotwobytestring);
StringEqual_Loop(lhs, lhs_instance_type, MachineType::Uint16(), rhs,
rhs_instance_type, MachineType::Uint16(), length, if_equal,
if_not_equal);
BIND(&if_onetwobytestring);
StringEqual_Loop(lhs, lhs_instance_type, MachineType::Uint8(), rhs,
rhs_instance_type, MachineType::Uint16(), length, if_equal,
if_not_equal);
BIND(&if_twoonebytestring);
StringEqual_Loop(lhs, lhs_instance_type, MachineType::Uint16(), rhs,
rhs_instance_type, MachineType::Uint8(), length, if_equal,
if_not_equal);
}
void StringBuiltinsAssembler::StringEqual_Loop(
Node* lhs, Node* lhs_instance_type, MachineType lhs_type, Node* rhs,
Node* rhs_instance_type, MachineType rhs_type, TNode<IntPtrT> length,
Label* if_equal, Label* if_not_equal) {
CSA_ASSERT(this, IsString(lhs));
CSA_ASSERT(this, IsString(rhs));
CSA_ASSERT(this, WordEqual(LoadStringLengthAsWord(lhs), length));
CSA_ASSERT(this, WordEqual(LoadStringLengthAsWord(rhs), length));
// Compute the effective offset of the first character.
Node* lhs_data = DirectStringData(lhs, lhs_instance_type);
Node* rhs_data = DirectStringData(rhs, rhs_instance_type);
// Loop over the {lhs} and {rhs} strings to see if they are equal.
TVARIABLE(IntPtrT, var_offset, IntPtrConstant(0));
Label loop(this, &var_offset);
Goto(&loop);
BIND(&loop);
{
// If {offset} equals {end}, no difference was found, so the
// strings are equal.
GotoIf(WordEqual(var_offset, length), if_equal);
// Load the next characters from {lhs} and {rhs}.
Node* lhs_value =
Load(lhs_type, lhs_data,
WordShl(var_offset, ElementSizeLog2Of(lhs_type.representation())));
Node* rhs_value =
Load(rhs_type, rhs_data,
WordShl(var_offset, ElementSizeLog2Of(rhs_type.representation())));
// Check if the characters match.
GotoIf(Word32NotEqual(lhs_value, rhs_value), if_not_equal);
// Advance to next character.
var_offset = IntPtrAdd(var_offset, IntPtrConstant(1));
Goto(&loop);
}
}
void StringBuiltinsAssembler::GenerateStringAt(char const* method_name,
TNode<Context> context,
Node* receiver,
TNode<Object> maybe_position,
TNode<Object> default_return,
StringAtAccessor accessor) {
// Check that {receiver} is coercible to Object and convert it to a String.
TNode<String> string = ToThisString(context, receiver, method_name);
// Convert the {position} to a Smi and check that it's in bounds of the
// {string}.
Label if_outofbounds(this, Label::kDeferred);
TNode<Number> position = ToInteger_Inline(
context, maybe_position, CodeStubAssembler::kTruncateMinusZero);
GotoIfNot(TaggedIsSmi(position), &if_outofbounds);
TNode<IntPtrT> index = SmiUntag(CAST(position));
TNode<IntPtrT> length = LoadStringLengthAsWord(string);
GotoIfNot(UintPtrLessThan(index, length), &if_outofbounds);
TNode<Object> result = accessor(string, length, index);
Return(result);
BIND(&if_outofbounds);
Return(default_return);
}
void StringBuiltinsAssembler::GenerateStringRelationalComparison(Node* context,
Node* left,
Node* right,
Operation op) {
VARIABLE(var_left, MachineRepresentation::kTagged, left);
VARIABLE(var_right, MachineRepresentation::kTagged, right);
Variable* input_vars[2] = {&var_left, &var_right};
Label if_less(this), if_equal(this), if_greater(this);
Label restart(this, 2, input_vars);
Goto(&restart);
BIND(&restart);
Node* lhs = var_left.value();
Node* rhs = var_right.value();
// Fast check to see if {lhs} and {rhs} refer to the same String object.
GotoIf(WordEqual(lhs, rhs), &if_equal);
// Load instance types of {lhs} and {rhs}.
Node* lhs_instance_type = LoadInstanceType(lhs);
Node* rhs_instance_type = LoadInstanceType(rhs);
// Combine the instance types into a single 16-bit value, so we can check
// both of them at once.
Node* both_instance_types = Word32Or(
lhs_instance_type, Word32Shl(rhs_instance_type, Int32Constant(8)));
// Check that both {lhs} and {rhs} are flat one-byte strings.
int const kBothSeqOneByteStringMask =
kStringEncodingMask | kStringRepresentationMask |
((kStringEncodingMask | kStringRepresentationMask) << 8);
int const kBothSeqOneByteStringTag =
kOneByteStringTag | kSeqStringTag |
((kOneByteStringTag | kSeqStringTag) << 8);
Label if_bothonebyteseqstrings(this), if_notbothonebyteseqstrings(this);
Branch(Word32Equal(Word32And(both_instance_types,
Int32Constant(kBothSeqOneByteStringMask)),
Int32Constant(kBothSeqOneByteStringTag)),
&if_bothonebyteseqstrings, &if_notbothonebyteseqstrings);
BIND(&if_bothonebyteseqstrings);
{
// Load the length of {lhs} and {rhs}.
TNode<IntPtrT> lhs_length = LoadStringLengthAsWord(lhs);
TNode<IntPtrT> rhs_length = LoadStringLengthAsWord(rhs);
// Determine the minimum length.
TNode<IntPtrT> length = IntPtrMin(lhs_length, rhs_length);
// Compute the effective offset of the first character.
TNode<IntPtrT> begin =
IntPtrConstant(SeqOneByteString::kHeaderSize - kHeapObjectTag);
// Compute the first offset after the string from the length.
TNode<IntPtrT> end = IntPtrAdd(begin, length);
// Loop over the {lhs} and {rhs} strings to see if they are equal.
TVARIABLE(IntPtrT, var_offset, begin);
Label loop(this, &var_offset);
Goto(&loop);
BIND(&loop);
{
// Check if {offset} equals {end}.
Label if_done(this), if_notdone(this);
Branch(WordEqual(var_offset, end), &if_done, &if_notdone);
BIND(&if_notdone);
{
// Load the next characters from {lhs} and {rhs}.
Node* lhs_value = Load(MachineType::Uint8(), lhs, var_offset);
Node* rhs_value = Load(MachineType::Uint8(), rhs, var_offset);
// Check if the characters match.
Label if_valueissame(this), if_valueisnotsame(this);
Branch(Word32Equal(lhs_value, rhs_value), &if_valueissame,
&if_valueisnotsame);
BIND(&if_valueissame);
{
// Advance to next character.
var_offset = IntPtrAdd(var_offset, IntPtrConstant(1));
}
Goto(&loop);
BIND(&if_valueisnotsame);
Branch(Uint32LessThan(lhs_value, rhs_value), &if_less, &if_greater);
}
BIND(&if_done);
{
// All characters up to the min length are equal, decide based on
// string length.
GotoIf(IntPtrEqual(lhs_length, rhs_length), &if_equal);
Branch(IntPtrLessThan(lhs_length, rhs_length), &if_less, &if_greater);
}
}
}
BIND(&if_notbothonebyteseqstrings);
{
// Try to unwrap indirect strings, restart the above attempt on success.
MaybeDerefIndirectStrings(&var_left, lhs_instance_type, &var_right,
rhs_instance_type, &restart);
// TODO(bmeurer): Add support for two byte string relational comparisons.
switch (op) {
case Operation::kLessThan:
TailCallRuntime(Runtime::kStringLessThan, context, lhs, rhs);
break;
case Operation::kLessThanOrEqual:
TailCallRuntime(Runtime::kStringLessThanOrEqual, context, lhs, rhs);
break;
case Operation::kGreaterThan:
TailCallRuntime(Runtime::kStringGreaterThan, context, lhs, rhs);
break;
case Operation::kGreaterThanOrEqual:
TailCallRuntime(Runtime::kStringGreaterThanOrEqual, context, lhs, rhs);
break;
default:
UNREACHABLE();
}
}
BIND(&if_less);
switch (op) {
case Operation::kLessThan:
case Operation::kLessThanOrEqual:
Return(TrueConstant());
break;
case Operation::kGreaterThan:
case Operation::kGreaterThanOrEqual:
Return(FalseConstant());
break;
default:
UNREACHABLE();
}
BIND(&if_equal);
switch (op) {
case Operation::kLessThan:
case Operation::kGreaterThan:
Return(FalseConstant());
break;
case Operation::kLessThanOrEqual:
case Operation::kGreaterThanOrEqual:
Return(TrueConstant());
break;
default:
UNREACHABLE();
}
BIND(&if_greater);
switch (op) {
case Operation::kLessThan:
case Operation::kLessThanOrEqual:
Return(FalseConstant());
break;
case Operation::kGreaterThan:
case Operation::kGreaterThanOrEqual:
Return(TrueConstant());
break;
default:
UNREACHABLE();
}
}
TF_BUILTIN(StringEqual, StringBuiltinsAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* left = Parameter(Descriptor::kLeft);
Node* right = Parameter(Descriptor::kRight);
GenerateStringEqual(context, left, right);
}
TF_BUILTIN(StringLessThan, StringBuiltinsAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* left = Parameter(Descriptor::kLeft);
Node* right = Parameter(Descriptor::kRight);
GenerateStringRelationalComparison(context, left, right,
Operation::kLessThan);
}
TF_BUILTIN(StringLessThanOrEqual, StringBuiltinsAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* left = Parameter(Descriptor::kLeft);
Node* right = Parameter(Descriptor::kRight);
GenerateStringRelationalComparison(context, left, right,
Operation::kLessThanOrEqual);
}
TF_BUILTIN(StringGreaterThan, StringBuiltinsAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* left = Parameter(Descriptor::kLeft);
Node* right = Parameter(Descriptor::kRight);
GenerateStringRelationalComparison(context, left, right,
Operation::kGreaterThan);
}
TF_BUILTIN(StringGreaterThanOrEqual, StringBuiltinsAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* left = Parameter(Descriptor::kLeft);
Node* right = Parameter(Descriptor::kRight);
GenerateStringRelationalComparison(context, left, right,
Operation::kGreaterThanOrEqual);
}
TF_BUILTIN(StringCharAt, StringBuiltinsAssembler) {
Node* receiver = Parameter(Descriptor::kReceiver);
Node* position = Parameter(Descriptor::kPosition);
// Load the character code at the {position} from the {receiver}.
TNode<Int32T> code = StringCharCodeAt(receiver, position);
// And return the single character string with only that {code}
TNode<String> result = StringFromCharCode(code);
Return(result);
}
TF_BUILTIN(StringCharCodeAt, StringBuiltinsAssembler) {
Node* receiver = Parameter(Descriptor::kReceiver);
Node* position = Parameter(Descriptor::kPosition);
// Load the character code at the {position} from the {receiver}.
TNode<Int32T> code = StringCharCodeAt(receiver, position);
// And return it as TaggedSigned value.
// TODO(turbofan): Allow builtins to return values untagged.
TNode<Smi> result = SmiFromWord32(code);
Return(result);
}
TF_BUILTIN(StringCodePointAt, StringBuiltinsAssembler) {
Node* receiver = Parameter(Descriptor::kReceiver);
Node* position = Parameter(Descriptor::kPosition);
// TODO(sigurds) Figure out if passing length as argument pays off.
TNode<IntPtrT> length = LoadStringLengthAsWord(receiver);
// Load the character code at the {position} from the {receiver}.
TNode<Int32T> code =
LoadSurrogatePairAt(receiver, length, position, UnicodeEncoding::UTF32);
// And return it as TaggedSigned value.
// TODO(turbofan): Allow builtins to return values untagged.
TNode<Smi> result = SmiFromWord32(code);
Return(result);
}
// -----------------------------------------------------------------------------
// ES6 section 21.1 String Objects
// ES6 #sec-string.fromcharcode
TF_BUILTIN(StringFromCharCode, CodeStubAssembler) {
// TODO(ishell): use constants from Descriptor once the JSFunction linkage
// arguments are reordered.
TNode<Int32T> argc =
UncheckedCast<Int32T>(Parameter(BuiltinDescriptor::kArgumentsCount));
Node* context = Parameter(BuiltinDescriptor::kContext);
CodeStubArguments arguments(this, ChangeInt32ToIntPtr(argc));
TNode<Smi> smi_argc = SmiTag(arguments.GetLength(INTPTR_PARAMETERS));
// Check if we have exactly one argument (plus the implicit receiver), i.e.
// if the parent frame is not an arguments adaptor frame.
Label if_oneargument(this), if_notoneargument(this);
Branch(Word32Equal(argc, Int32Constant(1)), &if_oneargument,
&if_notoneargument);
BIND(&if_oneargument);
{
// Single argument case, perform fast single character string cache lookup
// for one-byte code units, or fall back to creating a single character
// string on the fly otherwise.
Node* code = arguments.AtIndex(0);
Node* code32 = TruncateTaggedToWord32(context, code);
TNode<Int32T> code16 =
Signed(Word32And(code32, Int32Constant(String::kMaxUtf16CodeUnit)));
Node* result = StringFromCharCode(code16);
arguments.PopAndReturn(result);
}
Node* code16 = nullptr;
BIND(&if_notoneargument);
{
Label two_byte(this);
// Assume that the resulting string contains only one-byte characters.
Node* one_byte_result = AllocateSeqOneByteString(context, smi_argc);
TVARIABLE(IntPtrT, var_max_index);
var_max_index = IntPtrConstant(0);
// Iterate over the incoming arguments, converting them to 8-bit character
// codes. Stop if any of the conversions generates a code that doesn't fit
// in 8 bits.
CodeStubAssembler::VariableList vars({&var_max_index}, zone());
arguments.ForEach(vars, [this, context, &two_byte, &var_max_index, &code16,
one_byte_result](Node* arg) {
Node* code32 = TruncateTaggedToWord32(context, arg);
code16 = Word32And(code32, Int32Constant(String::kMaxUtf16CodeUnit));
GotoIf(
Int32GreaterThan(code16, Int32Constant(String::kMaxOneByteCharCode)),
&two_byte);
// The {code16} fits into the SeqOneByteString {one_byte_result}.
Node* offset = ElementOffsetFromIndex(
var_max_index, UINT8_ELEMENTS, CodeStubAssembler::INTPTR_PARAMETERS,
SeqOneByteString::kHeaderSize - kHeapObjectTag);
StoreNoWriteBarrier(MachineRepresentation::kWord8, one_byte_result,
offset, code16);
var_max_index = IntPtrAdd(var_max_index, IntPtrConstant(1));
});
arguments.PopAndReturn(one_byte_result);
BIND(&two_byte);
// At least one of the characters in the string requires a 16-bit
// representation. Allocate a SeqTwoByteString to hold the resulting
// string.
Node* two_byte_result = AllocateSeqTwoByteString(context, smi_argc);
// Copy the characters that have already been put in the 8-bit string into
// their corresponding positions in the new 16-bit string.
TNode<IntPtrT> zero = IntPtrConstant(0);
CopyStringCharacters(one_byte_result, two_byte_result, zero, zero,
var_max_index, String::ONE_BYTE_ENCODING,
String::TWO_BYTE_ENCODING);
// Write the character that caused the 8-bit to 16-bit fault.
Node* max_index_offset = ElementOffsetFromIndex(
var_max_index, UINT16_ELEMENTS, CodeStubAssembler::INTPTR_PARAMETERS,
SeqTwoByteString::kHeaderSize - kHeapObjectTag);
StoreNoWriteBarrier(MachineRepresentation::kWord16, two_byte_result,
max_index_offset, code16);
var_max_index = IntPtrAdd(var_max_index, IntPtrConstant(1));
// Resume copying the passed-in arguments from the same place where the
// 8-bit copy stopped, but this time copying over all of the characters
// using a 16-bit representation.
arguments.ForEach(
vars,
[this, context, two_byte_result, &var_max_index](Node* arg) {
Node* code32 = TruncateTaggedToWord32(context, arg);
Node* code16 =
Word32And(code32, Int32Constant(String::kMaxUtf16CodeUnit));
Node* offset = ElementOffsetFromIndex(
var_max_index, UINT16_ELEMENTS,
CodeStubAssembler::INTPTR_PARAMETERS,
SeqTwoByteString::kHeaderSize - kHeapObjectTag);
StoreNoWriteBarrier(MachineRepresentation::kWord16, two_byte_result,
offset, code16);
var_max_index = IntPtrAdd(var_max_index, IntPtrConstant(1));
},
var_max_index);
arguments.PopAndReturn(two_byte_result);
}
}
// ES6 #sec-string.prototype.charat
TF_BUILTIN(StringPrototypeCharAt, StringBuiltinsAssembler) {
TNode<Context> context = CAST(Parameter(Descriptor::kContext));
Node* receiver = Parameter(Descriptor::kReceiver);
TNode<Object> maybe_position = CAST(Parameter(Descriptor::kPosition));
GenerateStringAt("String.prototype.charAt", context, receiver, maybe_position,
EmptyStringConstant(),
[this](TNode<String> string, TNode<IntPtrT> length,
TNode<IntPtrT> index) {
TNode<Int32T> code = StringCharCodeAt(string, index);
return StringFromCharCode(code);
});
}
// ES6 #sec-string.prototype.charcodeat
TF_BUILTIN(StringPrototypeCharCodeAt, StringBuiltinsAssembler) {
TNode<Context> context = CAST(Parameter(Descriptor::kContext));
Node* receiver = Parameter(Descriptor::kReceiver);
TNode<Object> maybe_position = CAST(Parameter(Descriptor::kPosition));
GenerateStringAt("String.prototype.charCodeAt", context, receiver,
maybe_position, NanConstant(),
[this](TNode<String> receiver, TNode<IntPtrT> length,
TNode<IntPtrT> index) {
Node* value = StringCharCodeAt(receiver, index);
return SmiFromWord32(value);
});
}
// ES6 #sec-string.prototype.codepointat
TF_BUILTIN(StringPrototypeCodePointAt, StringBuiltinsAssembler) {
TNode<Context> context = CAST(Parameter(Descriptor::kContext));
Node* receiver = Parameter(Descriptor::kReceiver);
TNode<Object> maybe_position = CAST(Parameter(Descriptor::kPosition));
GenerateStringAt("String.prototype.codePointAt", context, receiver,
maybe_position, UndefinedConstant(),
[this](TNode<String> receiver, TNode<IntPtrT> length,
TNode<IntPtrT> index) {
Node* value = LoadSurrogatePairAt(receiver, length, index,
UnicodeEncoding::UTF32);
return SmiFromWord32(value);
});
}
// ES6 String.prototype.concat(...args)
// ES6 #sec-string.prototype.concat
TF_BUILTIN(StringPrototypeConcat, CodeStubAssembler) {
// TODO(ishell): use constants from Descriptor once the JSFunction linkage
// arguments are reordered.
CodeStubArguments arguments(
this, ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount)));
Node* receiver = arguments.GetReceiver();
Node* context = Parameter(BuiltinDescriptor::kContext);
// Check that {receiver} is coercible to Object and convert it to a String.
receiver = ToThisString(context, receiver, "String.prototype.concat");
// Concatenate all the arguments passed to this builtin.
VARIABLE(var_result, MachineRepresentation::kTagged);
var_result.Bind(receiver);
arguments.ForEach(
CodeStubAssembler::VariableList({&var_result}, zone()),
[this, context, &var_result](Node* arg) {
arg = ToString_Inline(context, arg);
var_result.Bind(CallStub(CodeFactory::StringAdd(isolate()), context,
var_result.value(), arg));
});
arguments.PopAndReturn(var_result.value());
}
void StringBuiltinsAssembler::StringIndexOf(
Node* const subject_string, Node* const search_string, Node* const position,
std::function<void(Node*)> f_return) {
CSA_ASSERT(this, IsString(subject_string));
CSA_ASSERT(this, IsString(search_string));
CSA_ASSERT(this, TaggedIsSmi(position));
TNode<IntPtrT> const int_zero = IntPtrConstant(0);
TNode<IntPtrT> const search_length = LoadStringLengthAsWord(search_string);
TNode<IntPtrT> const subject_length = LoadStringLengthAsWord(subject_string);
TNode<IntPtrT> const start_position = IntPtrMax(SmiUntag(position), int_zero);
Label zero_length_needle(this), return_minus_1(this);
{
GotoIf(IntPtrEqual(int_zero, search_length), &zero_length_needle);
// Check that the needle fits in the start position.
GotoIfNot(IntPtrLessThanOrEqual(search_length,
IntPtrSub(subject_length, start_position)),
&return_minus_1);
}
// If the string pointers are identical, we can just return 0. Note that this
// implies {start_position} == 0 since we've passed the check above.
Label return_zero(this);
GotoIf(WordEqual(subject_string, search_string), &return_zero);
// Try to unpack subject and search strings. Bail to runtime if either needs
// to be flattened.
ToDirectStringAssembler subject_to_direct(state(), subject_string);
ToDirectStringAssembler search_to_direct(state(), search_string);
Label call_runtime_unchecked(this, Label::kDeferred);
subject_to_direct.TryToDirect(&call_runtime_unchecked);
search_to_direct.TryToDirect(&call_runtime_unchecked);
// Load pointers to string data.
Node* const subject_ptr =
subject_to_direct.PointerToData(&call_runtime_unchecked);
Node* const search_ptr =
search_to_direct.PointerToData(&call_runtime_unchecked);
Node* const subject_offset = subject_to_direct.offset();
Node* const search_offset = search_to_direct.offset();
// Like String::IndexOf, the actual matching is done by the optimized
// SearchString method in string-search.h. Dispatch based on string instance
// types, then call straight into C++ for matching.
CSA_ASSERT(this, IntPtrGreaterThan(search_length, int_zero));
CSA_ASSERT(this, IntPtrGreaterThanOrEqual(start_position, int_zero));
CSA_ASSERT(this, IntPtrGreaterThanOrEqual(subject_length, start_position));
CSA_ASSERT(this,
IntPtrLessThanOrEqual(search_length,
IntPtrSub(subject_length, start_position)));
Label one_one(this), one_two(this), two_one(this), two_two(this);
DispatchOnStringEncodings(subject_to_direct.instance_type(),
search_to_direct.instance_type(), &one_one,
&one_two, &two_one, &two_two);
typedef const uint8_t onebyte_t;
typedef const uc16 twobyte_t;
BIND(&one_one);
{
Node* const adjusted_subject_ptr = PointerToStringDataAtIndex(
subject_ptr, subject_offset, String::ONE_BYTE_ENCODING);
Node* const adjusted_search_ptr = PointerToStringDataAtIndex(
search_ptr, search_offset, String::ONE_BYTE_ENCODING);
Label direct_memchr_call(this), generic_fast_path(this);
Branch(IntPtrEqual(search_length, IntPtrConstant(1)), &direct_memchr_call,
&generic_fast_path);
// An additional fast path that calls directly into memchr for 1-length
// search strings.
BIND(&direct_memchr_call);
{
Node* const string_addr = IntPtrAdd(adjusted_subject_ptr, start_position);
Node* const search_length = IntPtrSub(subject_length, start_position);
Node* const search_byte =
ChangeInt32ToIntPtr(Load(MachineType::Uint8(), adjusted_search_ptr));
Node* const memchr =
ExternalConstant(ExternalReference::libc_memchr_function(isolate()));
Node* const result_address =
CallCFunction3(MachineType::Pointer(), MachineType::Pointer(),
MachineType::IntPtr(), MachineType::UintPtr(), memchr,
string_addr, search_byte, search_length);
GotoIf(WordEqual(result_address, int_zero), &return_minus_1);
Node* const result_index =
IntPtrAdd(IntPtrSub(result_address, string_addr), start_position);
f_return(SmiTag(result_index));
}
BIND(&generic_fast_path);
{
Node* const result = CallSearchStringRaw<onebyte_t, onebyte_t>(
adjusted_subject_ptr, subject_length, adjusted_search_ptr,
search_length, start_position);
f_return(SmiTag(result));
}
}
BIND(&one_two);
{
Node* const adjusted_subject_ptr = PointerToStringDataAtIndex(
subject_ptr, subject_offset, String::ONE_BYTE_ENCODING);
Node* const adjusted_search_ptr = PointerToStringDataAtIndex(
search_ptr, search_offset, String::TWO_BYTE_ENCODING);
Node* const result = CallSearchStringRaw<onebyte_t, twobyte_t>(
adjusted_subject_ptr, subject_length, adjusted_search_ptr,
search_length, start_position);
f_return(SmiTag(result));
}
BIND(&two_one);
{
Node* const adjusted_subject_ptr = PointerToStringDataAtIndex(
subject_ptr, subject_offset, String::TWO_BYTE_ENCODING);
Node* const adjusted_search_ptr = PointerToStringDataAtIndex(
search_ptr, search_offset, String::ONE_BYTE_ENCODING);
Node* const result = CallSearchStringRaw<twobyte_t, onebyte_t>(
adjusted_subject_ptr, subject_length, adjusted_search_ptr,
search_length, start_position);
f_return(SmiTag(result));
}
BIND(&two_two);
{
Node* const adjusted_subject_ptr = PointerToStringDataAtIndex(
subject_ptr, subject_offset, String::TWO_BYTE_ENCODING);
Node* const adjusted_search_ptr = PointerToStringDataAtIndex(
search_ptr, search_offset, String::TWO_BYTE_ENCODING);
Node* const result = CallSearchStringRaw<twobyte_t, twobyte_t>(
adjusted_subject_ptr, subject_length, adjusted_search_ptr,
search_length, start_position);
f_return(SmiTag(result));
}
BIND(&return_minus_1);
f_return(SmiConstant(-1));
BIND(&return_zero);
f_return(SmiConstant(0));
BIND(&zero_length_needle);
{
Comment("0-length search_string");
f_return(SmiTag(IntPtrMin(subject_length, start_position)));
}
BIND(&call_runtime_unchecked);
{
// Simplified version of the runtime call where the types of the arguments
// are already known due to type checks in this stub.
Comment("Call Runtime Unchecked");
Node* result =
CallRuntime(Runtime::kStringIndexOfUnchecked, NoContextConstant(),
subject_string, search_string, position);
f_return(result);
}
}
// ES6 String.prototype.indexOf(searchString [, position])
// #sec-string.prototype.indexof
// Unchecked helper for builtins lowering.
TF_BUILTIN(StringIndexOf, StringBuiltinsAssembler) {
Node* receiver = Parameter(Descriptor::kReceiver);
Node* search_string = Parameter(Descriptor::kSearchString);
Node* position = Parameter(Descriptor::kPosition);
StringIndexOf(receiver, search_string, position,
[this](Node* result) { this->Return(result); });
}
// ES6 String.prototype.includes(searchString [, position])
// #sec-string.prototype.includes
TF_BUILTIN(StringPrototypeIncludes, StringIncludesIndexOfAssembler) {
Generate(kIncludes);
}
// ES6 String.prototype.indexOf(searchString [, position])
// #sec-string.prototype.indexof
TF_BUILTIN(StringPrototypeIndexOf, StringIncludesIndexOfAssembler) {
Generate(kIndexOf);
}
void StringIncludesIndexOfAssembler::Generate(SearchVariant variant) {
// TODO(ishell): use constants from Descriptor once the JSFunction linkage
// arguments are reordered.
Node* argc = Parameter(BuiltinDescriptor::kArgumentsCount);
Node* const context = Parameter(BuiltinDescriptor::kContext);
CodeStubArguments arguments(this, ChangeInt32ToIntPtr(argc));
Node* const receiver = arguments.GetReceiver();
// From now on use word-size argc value.
argc = arguments.GetLength(INTPTR_PARAMETERS);
VARIABLE(var_search_string, MachineRepresentation::kTagged);
VARIABLE(var_position, MachineRepresentation::kTagged);
Label argc_1(this), argc_2(this), call_runtime(this, Label::kDeferred),
fast_path(this);
GotoIf(IntPtrEqual(argc, IntPtrConstant(1)), &argc_1);
GotoIf(IntPtrGreaterThan(argc, IntPtrConstant(1)), &argc_2);
{
Comment("0 Argument case");
CSA_ASSERT(this, IntPtrEqual(argc, IntPtrConstant(0)));
Node* const undefined = UndefinedConstant();
var_search_string.Bind(undefined);
var_position.Bind(undefined);
Goto(&call_runtime);
}
BIND(&argc_1);
{
Comment("1 Argument case");
var_search_string.Bind(arguments.AtIndex(0));
var_position.Bind(SmiConstant(0));
Goto(&fast_path);
}
BIND(&argc_2);
{
Comment("2 Argument case");
var_search_string.Bind(arguments.AtIndex(0));
var_position.Bind(arguments.AtIndex(1));
GotoIfNot(TaggedIsSmi(var_position.value()), &call_runtime);
Goto(&fast_path);
}
BIND(&fast_path);
{
Comment("Fast Path");
Node* const search = var_search_string.value();
Node* const position = var_position.value();
GotoIf(TaggedIsSmi(receiver), &call_runtime);
GotoIf(TaggedIsSmi(search), &call_runtime);
GotoIfNot(IsString(receiver), &call_runtime);
GotoIfNot(IsString(search), &call_runtime);
StringIndexOf(receiver, search, position, [&](Node* result) {
CSA_ASSERT(this, TaggedIsSmi(result));
arguments.PopAndReturn((variant == kIndexOf)
? result
: SelectBooleanConstant(SmiGreaterThanOrEqual(
result, SmiConstant(0))));
});
}
BIND(&call_runtime);
{
Comment("Call Runtime");
Runtime::FunctionId runtime = variant == kIndexOf
? Runtime::kStringIndexOf
: Runtime::kStringIncludes;
Node* const result =
CallRuntime(runtime, context, receiver, var_search_string.value(),
var_position.value());
arguments.PopAndReturn(result);
}
}
void StringBuiltinsAssembler::RequireObjectCoercible(Node* const context,
Node* const value,
const char* method_name) {
Label out(this), throw_exception(this, Label::kDeferred);
Branch(IsNullOrUndefined(value), &throw_exception, &out);
BIND(&throw_exception);
TailCallRuntime(Runtime::kThrowCalledOnNullOrUndefined, context,
StringConstant(method_name));
BIND(&out);
}
void StringBuiltinsAssembler::MaybeCallFunctionAtSymbol(
Node* const context, Node* const object, Node* const maybe_string,
Handle<Symbol> symbol, const NodeFunction0& regexp_call,
const NodeFunction1& generic_call, CodeStubArguments* args) {
Label out(this);
// Smis definitely don't have an attached symbol.
GotoIf(TaggedIsSmi(object), &out);
Node* const object_map = LoadMap(object);
// Skip the slow lookup for Strings.
{
Label next(this);
GotoIfNot(IsStringInstanceType(LoadMapInstanceType(object_map)), &next);
Node* const native_context = LoadNativeContext(context);
Node* const initial_proto_initial_map = LoadContextElement(
native_context, Context::STRING_FUNCTION_PROTOTYPE_MAP_INDEX);
Node* const string_fun =
LoadContextElement(native_context, Context::STRING_FUNCTION_INDEX);
Node* const initial_map =
LoadObjectField(string_fun, JSFunction::kPrototypeOrInitialMapOffset);
Node* const proto_map = LoadMap(CAST(LoadMapPrototype(initial_map)));
Branch(WordEqual(proto_map, initial_proto_initial_map), &out, &next);
BIND(&next);
}
// Take the fast path for RegExps.
// There's two conditions: {object} needs to be a fast regexp, and
// {maybe_string} must be a string (we can't call ToString on the fast path
// since it may mutate {object}).
{
Label stub_call(this), slow_lookup(this);
GotoIf(TaggedIsSmi(maybe_string), &slow_lookup);
GotoIfNot(IsString(maybe_string), &slow_lookup);
RegExpBuiltinsAssembler regexp_asm(state());
regexp_asm.BranchIfFastRegExp(context, object, object_map, &stub_call,
&slow_lookup);
BIND(&stub_call);
// TODO(jgruber): Add a no-JS scope once it exists.
Node* const result = regexp_call();
if (args == nullptr) {
Return(result);
} else {
args->PopAndReturn(result);
}
BIND(&slow_lookup);
}
GotoIf(IsNullOrUndefined(object), &out);
// Fall back to a slow lookup of {object[symbol]}.
//
// The spec uses GetMethod({object}, {symbol}), which has a few quirks:
// * null values are turned into undefined, and
// * an exception is thrown if the value is not undefined, null, or callable.
// We handle the former by jumping to {out} for null values as well, while
// the latter is already handled by the Call({maybe_func}) operation.
Node* const maybe_func = GetProperty(context, object, symbol);
GotoIf(IsUndefined(maybe_func), &out);
GotoIf(IsNull(maybe_func), &out);
// Attempt to call the function.
Node* const result = generic_call(maybe_func);
if (args == nullptr) {
Return(result);
} else {
args->PopAndReturn(result);
}
BIND(&out);
}
compiler::Node* StringBuiltinsAssembler::IndexOfDollarChar(Node* const context,
Node* const string) {
CSA_ASSERT(this, IsString(string));
Node* const dollar_string = HeapConstant(
isolate()->factory()->LookupSingleCharacterStringFromCode('$'));
Node* const dollar_ix = CallBuiltin(Builtins::kStringIndexOf, context, string,
dollar_string, SmiConstant(0));
CSA_ASSERT(this, TaggedIsSmi(dollar_ix));
return dollar_ix;
}
compiler::Node* StringBuiltinsAssembler::GetSubstitution(
Node* context, Node* subject_string, Node* match_start_index,
Node* match_end_index, Node* replace_string) {
CSA_ASSERT(this, IsString(subject_string));
CSA_ASSERT(this, IsString(replace_string));
CSA_ASSERT(this, TaggedIsPositiveSmi(match_start_index));
CSA_ASSERT(this, TaggedIsPositiveSmi(match_end_index));
VARIABLE(var_result, MachineRepresentation::kTagged, replace_string);
Label runtime(this), out(this);
// In this primitive implementation we simply look for the next '$' char in
// {replace_string}. If it doesn't exist, we can simply return
// {replace_string} itself. If it does, then we delegate to
// String::GetSubstitution, passing in the index of the first '$' to avoid
// repeated scanning work.
// TODO(jgruber): Possibly extend this in the future to handle more complex
// cases without runtime calls.
Node* const dollar_index = IndexOfDollarChar(context, replace_string);
Branch(SmiIsNegative(dollar_index), &out, &runtime);
BIND(&runtime);
{
CSA_ASSERT(this, TaggedIsPositiveSmi(dollar_index));
Node* const matched =
CallBuiltin(Builtins::kSubString, context, subject_string,
match_start_index, match_end_index);
Node* const replacement_string =
CallRuntime(Runtime::kGetSubstitution, context, matched, subject_string,
match_start_index, replace_string, dollar_index);
var_result.Bind(replacement_string);
Goto(&out);
}
BIND(&out);
return var_result.value();
}
// ES6 #sec-string.prototype.repeat
TF_BUILTIN(StringPrototypeRepeat, StringBuiltinsAssembler) {
Label invalid_count(this), invalid_string_length(this),
return_emptystring(this);
TNode<Context> context = CAST(Parameter(Descriptor::kContext));
Node* const receiver = Parameter(Descriptor::kReceiver);
TNode<Object> count = CAST(Parameter(Descriptor::kCount));
Node* const string =
ToThisString(context, receiver, "String.prototype.repeat");
Node* const is_stringempty =
SmiEqual(LoadStringLengthAsSmi(string), SmiConstant(0));
VARIABLE(
var_count, MachineRepresentation::kTagged,
ToInteger_Inline(context, count, CodeStubAssembler::kTruncateMinusZero));
// Verifies a valid count and takes a fast path when the result will be an
// empty string.
{
Label if_count_isheapnumber(this, Label::kDeferred);
GotoIfNot(TaggedIsSmi(var_count.value()), &if_count_isheapnumber);
// If count is a SMI, throw a RangeError if less than 0 or greater than
// the maximum string length.
GotoIf(SmiLessThan(var_count.value(), SmiConstant(0)), &invalid_count);
GotoIf(SmiEqual(var_count.value(), SmiConstant(0)), &return_emptystring);
GotoIf(is_stringempty, &return_emptystring);
GotoIf(SmiGreaterThan(var_count.value(), SmiConstant(String::kMaxLength)),
&invalid_string_length);
Return(CallBuiltin(Builtins::kStringRepeat, context, string,
var_count.value()));
// If count is a Heap Number...
// 1) If count is Infinity, throw a RangeError exception
// 2) If receiver is an empty string, return an empty string
// 3) Otherwise, throw RangeError exception
BIND(&if_count_isheapnumber);
{
CSA_ASSERT(this, IsNumberNormalized(var_count.value()));
Node* const number_value = LoadHeapNumberValue(var_count.value());
GotoIf(Float64Equal(number_value, Float64Constant(V8_INFINITY)),
&invalid_count);
GotoIf(Float64LessThan(number_value, Float64Constant(0.0)),
&invalid_count);
Branch(is_stringempty, &return_emptystring, &invalid_string_length);
}
}
BIND(&return_emptystring);
Return(EmptyStringConstant());
BIND(&invalid_count);
{
CallRuntime(Runtime::kThrowRangeError, context,
SmiConstant(MessageTemplate::kInvalidCountValue),
var_count.value());
Unreachable();
}
BIND(&invalid_string_length);
{
CallRuntime(Runtime::kThrowInvalidStringLength, context);
Unreachable();
}
}
// Helper with less checks
TF_BUILTIN(StringRepeat, StringBuiltinsAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const string = Parameter(Descriptor::kString);
Node* const count = Parameter(Descriptor::kCount);
CSA_ASSERT(this, IsString(string));
CSA_ASSERT(this, Word32BinaryNot(IsEmptyString(string)));
CSA_ASSERT(this, TaggedIsPositiveSmi(count));
CSA_ASSERT(this, SmiLessThanOrEqual(count, SmiConstant(String::kMaxLength)));
// The string is repeated with the following algorithm:
// let n = count;
// let power_of_two_repeats = string;
// let result = "";
// while (true) {
// if (n & 1) result += s;
// n >>= 1;
// if (n === 0) return result;
// power_of_two_repeats += power_of_two_repeats;
// }
VARIABLE(var_result, MachineRepresentation::kTagged, EmptyStringConstant());
VARIABLE(var_temp, MachineRepresentation::kTagged, string);
VARIABLE(var_count, MachineRepresentation::kTagged, count);
Callable stringadd_callable =
CodeFactory::StringAdd(isolate(), STRING_ADD_CHECK_NONE, NOT_TENURED);
Label loop(this, {&var_count, &var_result, &var_temp}), return_result(this);
Goto(&loop);
BIND(&loop);
{
{
Label next(this);
GotoIfNot(SmiToWord32(SmiAnd(var_count.value(), SmiConstant(1))), &next);
var_result.Bind(CallStub(stringadd_callable, context, var_result.value(),
var_temp.value()));
Goto(&next);
BIND(&next);
}
var_count.Bind(SmiShr(var_count.value(), 1));
GotoIf(SmiEqual(var_count.value(), SmiConstant(0)), &return_result);
var_temp.Bind(CallStub(stringadd_callable, context, var_temp.value(),
var_temp.value()));
Goto(&loop);
}
BIND(&return_result);
Return(var_result.value());
}
// ES6 #sec-string.prototype.replace
TF_BUILTIN(StringPrototypeReplace, StringBuiltinsAssembler) {
Label out(this);
Node* const receiver = Parameter(Descriptor::kReceiver);
Node* const search = Parameter(Descriptor::kSearch);
Node* const replace = Parameter(Descriptor::kReplace);
Node* const context = Parameter(Descriptor::kContext);
Node* const smi_zero = SmiConstant(0);
RequireObjectCoercible(context, receiver, "String.prototype.replace");
// Redirect to replacer method if {search[@@replace]} is not undefined.
MaybeCallFunctionAtSymbol(
context, search, receiver, isolate()->factory()->replace_symbol(),
[=]() {
return CallBuiltin(Builtins::kRegExpReplace, context, search, receiver,
replace);
},
[=](Node* fn) {
Callable call_callable = CodeFactory::Call(isolate());
return CallJS(call_callable, context, fn, search, receiver, replace);
});
// Convert {receiver} and {search} to strings.
TNode<String> const subject_string = ToString_Inline(context, receiver);
TNode<String> const search_string = ToString_Inline(context, search);
TNode<Smi> const subject_length = LoadStringLengthAsSmi(subject_string);
TNode<Smi> const search_length = LoadStringLengthAsSmi(search_string);
// Fast-path single-char {search}, long cons {receiver}, and simple string
// {replace}.
{
Label next(this);
GotoIfNot(SmiEqual(search_length, SmiConstant(1)), &next);
GotoIfNot(SmiGreaterThan(subject_length, SmiConstant(0xFF)), &next);
GotoIf(TaggedIsSmi(replace), &next);
GotoIfNot(IsString(replace), &next);
Node* const subject_instance_type = LoadInstanceType(subject_string);
GotoIfNot(IsConsStringInstanceType(subject_instance_type), &next);
GotoIf(TaggedIsPositiveSmi(IndexOfDollarChar(context, replace)), &next);
// Searching by traversing a cons string tree and replace with cons of
// slices works only when the replaced string is a single character, being
// replaced by a simple string and only pays off for long strings.
// TODO(jgruber): Reevaluate if this is still beneficial.
// TODO(jgruber): TailCallRuntime when it correctly handles adapter frames.
Return(CallRuntime(Runtime::kStringReplaceOneCharWithString, context,
subject_string, search_string, replace));
BIND(&next);
}
// TODO(jgruber): Extend StringIndexOf to handle two-byte strings and
// longer substrings - we can handle up to 8 chars (one-byte) / 4 chars
// (2-byte).
Node* const match_start_index =
CallBuiltin(Builtins::kStringIndexOf, context, subject_string,
search_string, smi_zero);
CSA_ASSERT(this, TaggedIsSmi(match_start_index));
// Early exit if no match found.
{
Label next(this), return_subject(this);
GotoIfNot(SmiIsNegative(match_start_index), &next);
// The spec requires to perform ToString(replace) if the {replace} is not
// callable even if we are going to exit here.
// Since ToString() being applied to Smi does not have side effects for
// numbers we can skip it.
GotoIf(TaggedIsSmi(replace), &return_subject);
GotoIf(IsCallableMap(LoadMap(replace)), &return_subject);
// TODO(jgruber): Could introduce ToStringSideeffectsStub which only
// performs observable parts of ToString.
ToString_Inline(context, replace);
Goto(&return_subject);
BIND(&return_subject);
Return(subject_string);
BIND(&next);
}
Node* const match_end_index = SmiAdd(match_start_index, search_length);
Callable stringadd_callable =
CodeFactory::StringAdd(isolate(), STRING_ADD_CHECK_NONE, NOT_TENURED);
VARIABLE(var_result, MachineRepresentation::kTagged, EmptyStringConstant());
// Compute the prefix.
{
Label next(this);
GotoIf(SmiEqual(match_start_index, smi_zero), &next);
Node* const prefix =
CallBuiltin(Builtins::kSubString, context, subject_string, smi_zero,
match_start_index);
var_result.Bind(prefix);
Goto(&next);
BIND(&next);
}
// Compute the string to replace with.
Label if_iscallablereplace(this), if_notcallablereplace(this);
GotoIf(TaggedIsSmi(replace), &if_notcallablereplace);
Branch(IsCallableMap(LoadMap(replace)), &if_iscallablereplace,
&if_notcallablereplace);
BIND(&if_iscallablereplace);
{
Callable call_callable = CodeFactory::Call(isolate());
Node* const replacement =
CallJS(call_callable, context, replace, UndefinedConstant(),
search_string, match_start_index, subject_string);
Node* const replacement_string = ToString_Inline(context, replacement);
var_result.Bind(CallStub(stringadd_callable, context, var_result.value(),
replacement_string));
Goto(&out);
}
BIND(&if_notcallablereplace);
{
Node* const replace_string = ToString_Inline(context, replace);
Node* const replacement =
GetSubstitution(context, subject_string, match_start_index,
match_end_index, replace_string);
var_result.Bind(
CallStub(stringadd_callable, context, var_result.value(), replacement));
Goto(&out);
}
BIND(&out);
{
Node* const suffix =
CallBuiltin(Builtins::kSubString, context, subject_string,
match_end_index, subject_length);
Node* const result =
CallStub(stringadd_callable, context, var_result.value(), suffix);
Return(result);
}
}
class StringMatchSearchAssembler : public StringBuiltinsAssembler {
public:
explicit StringMatchSearchAssembler(compiler::CodeAssemblerState* state)
: StringBuiltinsAssembler(state) {}
protected:
enum Variant { kMatch, kSearch };
void Generate(Variant variant, const char* method_name, Node* const receiver,
Node* maybe_regexp, Node* const context) {
Label call_regexp_match_search(this);
Builtins::Name builtin;
Handle<Symbol> symbol;
if (variant == kMatch) {
builtin = Builtins::kRegExpMatchFast;
symbol = isolate()->factory()->match_symbol();
} else {
builtin = Builtins::kRegExpSearchFast;
symbol = isolate()->factory()->search_symbol();
}
RequireObjectCoercible(context, receiver, method_name);
MaybeCallFunctionAtSymbol(
context, maybe_regexp, receiver, symbol,
[=] { return CallBuiltin(builtin, context, maybe_regexp, receiver); },
[=](Node* fn) {
Callable call_callable = CodeFactory::Call(isolate());
return CallJS(call_callable, context, fn, maybe_regexp, receiver);
});
// maybe_regexp is not a RegExp nor has [@@match / @@search] property.
{
RegExpBuiltinsAssembler regexp_asm(state());
Node* const receiver_string = ToString_Inline(context, receiver);
Node* const pattern = Select(
IsUndefined(maybe_regexp), [=] { return EmptyStringConstant(); },
[=] { return ToString_Inline(context, maybe_regexp); },
MachineRepresentation::kTagged);
// Create RegExp
// TODO(pwong): This could be factored out as a helper (RegExpCreate) that
// also does the "is fast" checks.
Node* const native_context = LoadNativeContext(context);
Node* const regexp_function =
LoadContextElement(native_context, Context::REGEXP_FUNCTION_INDEX);
Node* const initial_map = LoadObjectField(
regexp_function, JSFunction::kPrototypeOrInitialMapOffset);
Node* const regexp = CallRuntime(
Runtime::kRegExpInitializeAndCompile, context,
AllocateJSObjectFromMap(initial_map), pattern, EmptyStringConstant());
Label fast_path(this), slow_path(this);
regexp_asm.BranchIfFastRegExp(context, regexp, initial_map, &fast_path,
&slow_path);
BIND(&fast_path);
Return(CallBuiltin(builtin, context, regexp, receiver_string));
BIND(&slow_path);
{
Node* const maybe_func = GetProperty(context, regexp, symbol);
Callable call_callable = CodeFactory::Call(isolate());
Return(CallJS(call_callable, context, maybe_func, regexp,
receiver_string));
}
}
}
};
// ES6 #sec-string.prototype.match
TF_BUILTIN(StringPrototypeMatch, StringMatchSearchAssembler) {
Node* const receiver = Parameter(Descriptor::kReceiver);
Node* const maybe_regexp = Parameter(Descriptor::kRegexp);
Node* const context = Parameter(Descriptor::kContext);
Generate(kMatch, "String.prototype.match", receiver, maybe_regexp, context);
}
class StringPadAssembler : public StringBuiltinsAssembler {
public:
explicit StringPadAssembler(compiler::CodeAssemblerState* state)
: StringBuiltinsAssembler(state) {}
protected:
enum Variant { kStart, kEnd };
void Generate(Variant variant, const char* method_name) {
Node* const context = Parameter(BuiltinDescriptor::kContext);
Node* argc =
ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount));
CodeStubArguments arguments(this, argc);
Node* const receiver = arguments.GetReceiver();
Node* const receiver_string = ToThisString(context, receiver, method_name);
TNode<Smi> const string_length = LoadStringLengthAsSmi(receiver_string);
TVARIABLE(String, var_fill_string, StringConstant(" "));
TVARIABLE(IntPtrT, var_fill_length, IntPtrConstant(1));
Label argc_2(this), dont_pad(this), invalid_string_length(this), pad(this);
// If no max_length was provided, return the string.
GotoIf(IntPtrEqual(argc, IntPtrConstant(0)), &dont_pad);
Node* const max_length = ToLength_Inline(context, arguments.AtIndex(0));
CSA_ASSERT(this, IsNumberNormalized(max_length));
// Throw if max_length is not a smi or greater than the max string length.
GotoIfNot(Word32And(TaggedIsSmi(max_length),
SmiLessThanOrEqual(max_length,
SmiConstant(String::kMaxLength))),
&invalid_string_length);
// If the max_length is less than length of the string, return the string.
CSA_ASSERT(this, TaggedIsPositiveSmi(max_length));
GotoIf(SmiLessThanOrEqual(max_length, string_length), &dont_pad);
Branch(IntPtrEqual(argc, IntPtrConstant(1)), &pad, &argc_2);
BIND(&argc_2);
{
Node* const fill = arguments.AtIndex(1);
GotoIf(IsUndefined(fill), &pad);
var_fill_string = ToString_Inline(context, fill);
var_fill_length = LoadStringLengthAsWord(var_fill_string);
Branch(IntPtrGreaterThan(var_fill_length, IntPtrConstant(0)), &pad,
&dont_pad);
}
BIND(&pad);
{
CSA_ASSERT(this, IntPtrGreaterThan(var_fill_length, IntPtrConstant(0)));
CSA_ASSERT(this, SmiGreaterThan(max_length, string_length));
Callable stringadd_callable =
CodeFactory::StringAdd(isolate(), STRING_ADD_CHECK_NONE, NOT_TENURED);
TNode<Smi> const pad_length = SmiSub(max_length, string_length);
VARIABLE(var_pad, MachineRepresentation::kTagged);
Label single_char_fill(this), multi_char_fill(this), return_result(this);
Branch(IntPtrEqual(var_fill_length, IntPtrConstant(1)), &single_char_fill,
&multi_char_fill);
// Fast path for a single character fill. No need to calculate number of
// repetitions or remainder.
BIND(&single_char_fill);
{
var_pad.Bind(CallBuiltin(Builtins::kStringRepeat, context,
static_cast<Node*>(var_fill_string),
pad_length));
Goto(&return_result);
}
BIND(&multi_char_fill);
{
TNode<Int32T> const fill_length_word32 =
TruncateWordToWord32(var_fill_length);
TNode<Int32T> const pad_length_word32 = SmiToWord32(pad_length);
TNode<Int32T> const repetitions_word32 =
Int32Div(pad_length_word32, fill_length_word32);
TNode<Int32T> const remaining_word32 =
Int32Mod(pad_length_word32, fill_length_word32);
var_pad.Bind(CallBuiltin(Builtins::kStringRepeat, context,
static_cast<Node*>(var_fill_string),
SmiFromWord32(repetitions_word32)));
GotoIfNot(remaining_word32, &return_result);
{
Node* const remainder_string =
CallBuiltin(Builtins::kSubString, context,
static_cast<Node*>(var_fill_string), SmiConstant(0),
SmiFromWord32(remaining_word32));
var_pad.Bind(CallStub(stringadd_callable, context, var_pad.value(),
remainder_string));
Goto(&return_result);
}
}
BIND(&return_result);
CSA_ASSERT(this,
SmiEqual(pad_length, LoadStringLengthAsSmi(var_pad.value())));
arguments.PopAndReturn(variant == kStart
? CallStub(stringadd_callable, context,
var_pad.value(), receiver_string)
: CallStub(stringadd_callable, context,
receiver_string, var_pad.value()));
}
BIND(&dont_pad);
arguments.PopAndReturn(receiver_string);
BIND(&invalid_string_length);
{
CallRuntime(Runtime::kThrowInvalidStringLength, context);
Unreachable();
}
}
};
TF_BUILTIN(StringPrototypePadEnd, StringPadAssembler) {
Generate(kEnd, "String.prototype.padEnd");
}
TF_BUILTIN(StringPrototypePadStart, StringPadAssembler) {
Generate(kStart, "String.prototype.padStart");
}
// ES6 #sec-string.prototype.search
TF_BUILTIN(StringPrototypeSearch, StringMatchSearchAssembler) {
Node* const receiver = Parameter(Descriptor::kReceiver);
Node* const maybe_regexp = Parameter(Descriptor::kRegexp);
Node* const context = Parameter(Descriptor::kContext);
Generate(kSearch, "String.prototype.search", receiver, maybe_regexp, context);
}
// ES6 section 21.1.3.18 String.prototype.slice ( start, end )
TF_BUILTIN(StringPrototypeSlice, StringBuiltinsAssembler) {
Label out(this);
VARIABLE(var_start, MachineRepresentation::kTagged);
VARIABLE(var_end, MachineRepresentation::kTagged);
const int kStart = 0;
const int kEnd = 1;
Node* argc =
ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount));
CodeStubArguments args(this, argc);
Node* const receiver = args.GetReceiver();
Node* const start = args.GetOptionalArgumentValue(kStart);
TNode<Object> end = CAST(args.GetOptionalArgumentValue(kEnd));
TNode<Context> context = CAST(Parameter(BuiltinDescriptor::kContext));
TNode<Smi> const smi_zero = SmiConstant(0);
// 1. Let O be ? RequireObjectCoercible(this value).
RequireObjectCoercible(context, receiver, "String.prototype.slice");
// 2. Let S be ? ToString(O).
Node* const subject_string =
CallBuiltin(Builtins::kToString, context, receiver);
// 3. Let len be the number of elements in S.
TNode<Smi> const length = LoadStringLengthAsSmi(subject_string);
// Conversions and bounds-checks for {start}.
ConvertAndBoundsCheckStartArgument(context, &var_start, start, length);
// 5. If end is undefined, let intEnd be len;
var_end.Bind(length);
GotoIf(IsUndefined(end), &out);
// else let intEnd be ? ToInteger(end).
Node* const end_int =
ToInteger_Inline(context, end, CodeStubAssembler::kTruncateMinusZero);
// 7. If intEnd < 0, let to be max(len + intEnd, 0);
// otherwise let to be min(intEnd, len).
Label if_issmi(this), if_isheapnumber(this, Label::kDeferred);
Branch(TaggedIsSmi(end_int), &if_issmi, &if_isheapnumber);
BIND(&if_issmi);
{
Node* const length_plus_end = SmiAdd(length, end_int);
var_end.Bind(Select(SmiLessThan(end_int, smi_zero),
[&] { return SmiMax(length_plus_end, smi_zero); },
[&] { return SmiMin(length, end_int); },
MachineRepresentation::kTagged));
Goto(&out);
}
BIND(&if_isheapnumber);
{
// If {end} is a heap number, it is definitely out of bounds. If it is
// negative, {int_end} = max({length} + {int_end}),0) = 0'. If it is
// positive, set {int_end} to {length} which ultimately results in
// returning an empty string.
Node* const float_zero = Float64Constant(0.);
Node* const end_float = LoadHeapNumberValue(end_int);
var_end.Bind(SelectTaggedConstant<Smi>(
Float64LessThan(end_float, float_zero), smi_zero, length));
Goto(&out);
}
Label return_emptystring(this);
BIND(&out);
{
GotoIf(SmiLessThanOrEqual(var_end.value(), var_start.value()),
&return_emptystring);
Node* const result =
SubString(context, subject_string, var_start.value(), var_end.value(),
SubStringFlags::FROM_TO_ARE_BOUNDED);
args.PopAndReturn(result);
}
BIND(&return_emptystring);
args.PopAndReturn(EmptyStringConstant());
}
// ES6 section 21.1.3.19 String.prototype.split ( separator, limit )
TF_BUILTIN(StringPrototypeSplit, StringBuiltinsAssembler) {
const int kSeparatorArg = 0;
const int kLimitArg = 1;
Node* const argc =
ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount));
CodeStubArguments args(this, argc);
Node* const receiver = args.GetReceiver();
Node* const separator = args.GetOptionalArgumentValue(kSeparatorArg);
Node* const limit = args.GetOptionalArgumentValue(kLimitArg);
Node* const context = Parameter(BuiltinDescriptor::kContext);
Node* const smi_zero = SmiConstant(0);
RequireObjectCoercible(context, receiver, "String.prototype.split");
// Redirect to splitter method if {separator[@@split]} is not undefined.
MaybeCallFunctionAtSymbol(
context, separator, receiver, isolate()->factory()->split_symbol(),
[=]() {
return CallBuiltin(Builtins::kRegExpSplit, context, separator, receiver,
limit);
},
[=](Node* fn) {
Callable call_callable = CodeFactory::Call(isolate());
return CallJS(call_callable, context, fn, separator, receiver, limit);
},
&args);
// String and integer conversions.
Node* const subject_string = ToString_Inline(context, receiver);
Node* const limit_number =
Select(IsUndefined(limit), [=]() { return NumberConstant(kMaxUInt32); },
[=]() { return ToUint32(context, limit); },
MachineRepresentation::kTagged);
Node* const separator_string = ToString_Inline(context, separator);
// Shortcut for {limit} == 0.
{
Label next(this);
GotoIfNot(SmiEqual(limit_number, smi_zero), &next);
const ElementsKind kind = PACKED_ELEMENTS;
Node* const native_context = LoadNativeContext(context);
Node* const array_map = LoadJSArrayElementsMap(kind, native_context);
Node* const length = smi_zero;
Node* const capacity = IntPtrConstant(0);
Node* const result = AllocateJSArray(kind, array_map, capacity, length);
args.PopAndReturn(result);
BIND(&next);
}
// ECMA-262 says that if {separator} is undefined, the result should
// be an array of size 1 containing the entire string.
{
Label next(this);
GotoIfNot(IsUndefined(separator), &next);
const ElementsKind kind = PACKED_ELEMENTS;
Node* const native_context = LoadNativeContext(context);
Node* const array_map = LoadJSArrayElementsMap(kind, native_context);
Node* const length = SmiConstant(1);
Node* const capacity = IntPtrConstant(1);
Node* const result = AllocateJSArray(kind, array_map, capacity, length);
Node* const fixed_array = LoadElements(result);
StoreFixedArrayElement(fixed_array, 0, subject_string);
args.PopAndReturn(result);
BIND(&next);
}
// If the separator string is empty then return the elements in the subject.
{
Label next(this);
GotoIfNot(SmiEqual(LoadStringLengthAsSmi(separator_string), SmiConstant(0)),
&next);
Node* const result = CallRuntime(Runtime::kStringToArray, context,
subject_string, limit_number);
args.PopAndReturn(result);
BIND(&next);
}
Node* const result =
CallRuntime(Runtime::kStringSplit, context, subject_string,
separator_string, limit_number);
args.PopAndReturn(result);
}
// ES6 #sec-string.prototype.substr
TF_BUILTIN(StringPrototypeSubstr, StringBuiltinsAssembler) {
const int kStartArg = 0;
const int kLengthArg = 1;
Node* const argc =
ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount));
CodeStubArguments args(this, argc);
Node* const receiver = args.GetReceiver();
Node* const start = args.GetOptionalArgumentValue(kStartArg);
TNode<Object> length = CAST(args.GetOptionalArgumentValue(kLengthArg));
TNode<Context> context = CAST(Parameter(BuiltinDescriptor::kContext));
Label out(this);
TVARIABLE(Smi, var_start);
TVARIABLE(Number, var_length);
TNode<Smi> const zero = SmiConstant(0);
// Check that {receiver} is coercible to Object and convert it to a String.
Node* const string =
ToThisString(context, receiver, "String.prototype.substr");
TNode<Smi> const string_length = LoadStringLengthAsSmi(string);
// Conversions and bounds-checks for {start}.
ConvertAndBoundsCheckStartArgument(context, &var_start, start, string_length);
// Conversions and bounds-checks for {length}.
Label if_issmi(this), if_isheapnumber(this, Label::kDeferred);
// Default to {string_length} if {length} is undefined.
{
Label if_isundefined(this, Label::kDeferred), if_isnotundefined(this);
Branch(IsUndefined(length), &if_isundefined, &if_isnotundefined);
BIND(&if_isundefined);
var_length = string_length;
Goto(&if_issmi);
BIND(&if_isnotundefined);
var_length = ToInteger_Inline(context, length,
CodeStubAssembler::kTruncateMinusZero);
}
TVARIABLE(Smi, var_result_length);
Branch(TaggedIsSmi(var_length), &if_issmi, &if_isheapnumber);
// Set {length} to min(max({length}, 0), {string_length} - {start}
BIND(&if_issmi);
{
TNode<Smi> const positive_length = SmiMax(CAST(var_length), zero);
TNode<Smi> const minimal_length = SmiSub(string_length, var_start);
var_result_length = SmiMin(positive_length, minimal_length);
GotoIfNot(SmiLessThanOrEqual(var_result_length, zero), &out);
args.PopAndReturn(EmptyStringConstant());
}
BIND(&if_isheapnumber);
{
// If {length} is a heap number, it is definitely out of bounds. There are
// two cases according to the spec: if it is negative, "" is returned; if
// it is positive, then length is set to {string_length} - {start}.
CSA_ASSERT(this, IsHeapNumber(var_length));
Label if_isnegative(this), if_ispositive(this);
TNode<Float64T> const float_zero = Float64Constant(0.);
TNode<Float64T> const length_float = LoadHeapNumberValue(CAST(var_length));
Branch(Float64LessThan(length_float, float_zero), &if_isnegative,
&if_ispositive);
BIND(&if_isnegative);
args.PopAndReturn(EmptyStringConstant());
BIND(&if_ispositive);
{
var_result_length = SmiSub(string_length, var_start);
GotoIfNot(SmiLessThanOrEqual(var_result_length, zero), &out);
args.PopAndReturn(EmptyStringConstant());
}
}
BIND(&out);
{
TNode<Smi> const end = SmiAdd(var_start, var_result_length);
Node* const result = SubString(context, string, var_start, end);
args.PopAndReturn(result);
}
}
TNode<Smi> StringBuiltinsAssembler::ToSmiBetweenZeroAnd(
SloppyTNode<Context> context, SloppyTNode<Object> value,
SloppyTNode<Smi> limit) {
Label out(this);
TVARIABLE(Smi, var_result);
TNode<Object> const value_int =
ToInteger_Inline(context, value, CodeStubAssembler::kTruncateMinusZero);
Label if_issmi(this), if_isnotsmi(this, Label::kDeferred);
Branch(TaggedIsSmi(value_int), &if_issmi, &if_isnotsmi);
BIND(&if_issmi);
{
Label if_isinbounds(this), if_isoutofbounds(this, Label::kDeferred);
Branch(SmiAbove(value_int, limit), &if_isoutofbounds, &if_isinbounds);
BIND(&if_isinbounds);
{
var_result = CAST(value_int);
Goto(&out);
}
BIND(&if_isoutofbounds);
{
TNode<Smi> const zero = SmiConstant(0);
var_result =
SelectTaggedConstant(SmiLessThan(value_int, zero), zero, limit);
Goto(&out);
}
}
BIND(&if_isnotsmi);
{
// {value} is a heap number - in this case, it is definitely out of bounds.
TNode<HeapNumber> value_int_hn = CAST(value_int);
TNode<Float64T> const float_zero = Float64Constant(0.);
TNode<Smi> const smi_zero = SmiConstant(0);
TNode<Float64T> const value_float = LoadHeapNumberValue(value_int_hn);
var_result = SelectTaggedConstant(Float64LessThan(value_float, float_zero),
smi_zero, limit);
Goto(&out);
}
BIND(&out);
return var_result;
}
TF_BUILTIN(SubString, CodeStubAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* string = Parameter(Descriptor::kString);
Node* from = Parameter(Descriptor::kFrom);
Node* to = Parameter(Descriptor::kTo);
Return(SubString(context, string, from, to));
}
// ES6 #sec-string.prototype.substring
TF_BUILTIN(StringPrototypeSubstring, StringBuiltinsAssembler) {
const int kStartArg = 0;
const int kEndArg = 1;
Node* const argc =
ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount));
CodeStubArguments args(this, argc);
Node* const receiver = args.GetReceiver();
Node* const start = args.GetOptionalArgumentValue(kStartArg);
Node* const end = args.GetOptionalArgumentValue(kEndArg);
Node* const context = Parameter(BuiltinDescriptor::kContext);
Label out(this);
VARIABLE(var_start, MachineRepresentation::kTagged);
VARIABLE(var_end, MachineRepresentation::kTagged);
// Check that {receiver} is coercible to Object and convert it to a String.
Node* const string =
ToThisString(context, receiver, "String.prototype.substring");
Node* const length = LoadStringLengthAsSmi(string);
// Conversion and bounds-checks for {start}.
var_start.Bind(ToSmiBetweenZeroAnd(context, start, length));
// Conversion and bounds-checks for {end}.
{
var_end.Bind(length);
GotoIf(IsUndefined(end), &out);
var_end.Bind(ToSmiBetweenZeroAnd(context, end, length));
Label if_endislessthanstart(this);
Branch(SmiLessThan(var_end.value(), var_start.value()),
&if_endislessthanstart, &out);
BIND(&if_endislessthanstart);
{
Node* const tmp = var_end.value();
var_end.Bind(var_start.value());
var_start.Bind(tmp);
Goto(&out);
}
}
BIND(&out);
{
Node* result =
SubString(context, string, var_start.value(), var_end.value());
args.PopAndReturn(result);
}
}
// ES6 #sec-string.prototype.trim
TF_BUILTIN(StringPrototypeTrim, StringTrimAssembler) {
Generate(String::kTrim, "String.prototype.trim");
}
// Non-standard WebKit extension
TF_BUILTIN(StringPrototypeTrimLeft, StringTrimAssembler) {
Generate(String::kTrimLeft, "String.prototype.trimLeft");
}
// Non-standard WebKit extension
TF_BUILTIN(StringPrototypeTrimRight, StringTrimAssembler) {
Generate(String::kTrimRight, "String.prototype.trimRight");
}
void StringTrimAssembler::Generate(String::TrimMode mode,
const char* method_name) {
Label return_emptystring(this), if_runtime(this);
Node* const argc = Parameter(BuiltinDescriptor::kArgumentsCount);
Node* const context = Parameter(BuiltinDescriptor::kContext);
CodeStubArguments arguments(this, ChangeInt32ToIntPtr(argc));
Node* const receiver = arguments.GetReceiver();
// Check that {receiver} is coercible to Object and convert it to a String.
Node* const string = ToThisString(context, receiver, method_name);
TNode<IntPtrT> const string_length = LoadStringLengthAsWord(string);
ToDirectStringAssembler to_direct(state(), string);
to_direct.TryToDirect(&if_runtime);
Node* const string_data = to_direct.PointerToData(&if_runtime);
Node* const instance_type = to_direct.instance_type();
Node* const is_stringonebyte = IsOneByteStringInstanceType(instance_type);
Node* const string_data_offset = to_direct.offset();
TVARIABLE(IntPtrT, var_start, IntPtrConstant(0));
TVARIABLE(IntPtrT, var_end, IntPtrSub(string_length, IntPtrConstant(1)));
if (mode == String::kTrimLeft || mode == String::kTrim) {
ScanForNonWhiteSpaceOrLineTerminator(string_data, string_data_offset,
is_stringonebyte, &var_start,
string_length, 1, &return_emptystring);
}
if (mode == String::kTrimRight || mode == String::kTrim) {
ScanForNonWhiteSpaceOrLineTerminator(
string_data, string_data_offset, is_stringonebyte, &var_end,
IntPtrConstant(-1), -1, &return_emptystring);
}
arguments.PopAndReturn(SubString(context, string, SmiTag(var_start),
SmiAdd(SmiTag(var_end), SmiConstant(1)),
SubStringFlags::FROM_TO_ARE_BOUNDED));
BIND(&if_runtime);
arguments.PopAndReturn(
CallRuntime(Runtime::kStringTrim, context, string, SmiConstant(mode)));
BIND(&return_emptystring);
arguments.PopAndReturn(EmptyStringConstant());
}
void StringTrimAssembler::ScanForNonWhiteSpaceOrLineTerminator(
Node* const string_data, Node* const string_data_offset,
Node* const is_stringonebyte, Variable* const var_index, Node* const end,
int increment, Label* const if_none_found) {
Label if_stringisonebyte(this), out(this);
GotoIf(is_stringonebyte, &if_stringisonebyte);
// Two Byte String
BuildLoop(
var_index, end, increment, if_none_found, &out, [&](Node* const index) {
return Load(
MachineType::Uint16(), string_data,
WordShl(IntPtrAdd(index, string_data_offset), IntPtrConstant(1)));
});
BIND(&if_stringisonebyte);
BuildLoop(var_index, end, increment, if_none_found, &out,
[&](Node* const index) {
return Load(MachineType::Uint8(), string_data,
IntPtrAdd(index, string_data_offset));
});
BIND(&out);
}
void StringTrimAssembler::BuildLoop(Variable* const var_index, Node* const end,
int increment, Label* const if_none_found,
Label* const out,
std::function<Node*(Node*)> get_character) {
Label loop(this, var_index);
Goto(&loop);
BIND(&loop);
{
Node* const index = var_index->value();
GotoIf(IntPtrEqual(index, end), if_none_found);
GotoIfNotWhiteSpaceOrLineTerminator(
UncheckedCast<Uint32T>(get_character(index)), out);
Increment(var_index, increment);
Goto(&loop);
}
}
void StringTrimAssembler::GotoIfNotWhiteSpaceOrLineTerminator(
Node* const char_code, Label* const if_not_whitespace) {
Label out(this);
// 0x0020 - SPACE (Intentionally out of order to fast path a commmon case)
GotoIf(Word32Equal(char_code, Int32Constant(0x0020)), &out);
// 0x0009 - HORIZONTAL TAB
GotoIf(Uint32LessThan(char_code, Int32Constant(0x0009)), if_not_whitespace);
// 0x000A - LINE FEED OR NEW LINE
// 0x000B - VERTICAL TAB
// 0x000C - FORMFEED
// 0x000D - HORIZONTAL TAB
GotoIf(Uint32LessThanOrEqual(char_code, Int32Constant(0x000D)), &out);
// Common Non-whitespace characters
GotoIf(Uint32LessThan(char_code, Int32Constant(0x00A0)), if_not_whitespace);
// 0x00A0 - NO-BREAK SPACE
GotoIf(Word32Equal(char_code, Int32Constant(0x00A0)), &out);
// 0x1680 - Ogham Space Mark
GotoIf(Word32Equal(char_code, Int32Constant(0x1680)), &out);
// 0x2000 - EN QUAD
GotoIf(Uint32LessThan(char_code, Int32Constant(0x2000)), if_not_whitespace);
// 0x2001 - EM QUAD
// 0x2002 - EN SPACE
// 0x2003 - EM SPACE
// 0x2004 - THREE-PER-EM SPACE
// 0x2005 - FOUR-PER-EM SPACE
// 0x2006 - SIX-PER-EM SPACE
// 0x2007 - FIGURE SPACE
// 0x2008 - PUNCTUATION SPACE
// 0x2009 - THIN SPACE
// 0x200A - HAIR SPACE
GotoIf(Uint32LessThanOrEqual(char_code, Int32Constant(0x200A)), &out);
// 0x2028 - LINE SEPARATOR
GotoIf(Word32Equal(char_code, Int32Constant(0x2028)), &out);
// 0x2029 - PARAGRAPH SEPARATOR
GotoIf(Word32Equal(char_code, Int32Constant(0x2029)), &out);
// 0x202F - NARROW NO-BREAK SPACE
GotoIf(Word32Equal(char_code, Int32Constant(0x202F)), &out);
// 0x205F - MEDIUM MATHEMATICAL SPACE
GotoIf(Word32Equal(char_code, Int32Constant(0x205F)), &out);
// 0xFEFF - BYTE ORDER MARK
GotoIf(Word32Equal(char_code, Int32Constant(0xFEFF)), &out);
// 0x3000 - IDEOGRAPHIC SPACE
Branch(Word32Equal(char_code, Int32Constant(0x3000)), &out,
if_not_whitespace);
BIND(&out);
}
// ES6 #sec-string.prototype.tostring
TF_BUILTIN(StringPrototypeToString, CodeStubAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* receiver = Parameter(Descriptor::kReceiver);
Node* result = ToThisValue(context, receiver, PrimitiveType::kString,
"String.prototype.toString");
Return(result);
}
// ES6 #sec-string.prototype.valueof
TF_BUILTIN(StringPrototypeValueOf, CodeStubAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* receiver = Parameter(Descriptor::kReceiver);
Node* result = ToThisValue(context, receiver, PrimitiveType::kString,
"String.prototype.valueOf");
Return(result);
}
TF_BUILTIN(StringPrototypeIterator, CodeStubAssembler) {
Node* context = Parameter(Descriptor::kContext);
Node* receiver = Parameter(Descriptor::kReceiver);
Node* string =
ToThisString(context, receiver, "String.prototype[Symbol.iterator]");
Node* native_context = LoadNativeContext(context);
Node* map =
LoadContextElement(native_context, Context::STRING_ITERATOR_MAP_INDEX);
Node* iterator = Allocate(JSStringIterator::kSize);
StoreMapNoWriteBarrier(iterator, map);
StoreObjectFieldRoot(iterator, JSValue::kPropertiesOrHashOffset,
Heap::kEmptyFixedArrayRootIndex);
StoreObjectFieldRoot(iterator, JSObject::kElementsOffset,
Heap::kEmptyFixedArrayRootIndex);
StoreObjectFieldNoWriteBarrier(iterator, JSStringIterator::kStringOffset,
string);
Node* index = SmiConstant(0);
StoreObjectFieldNoWriteBarrier(iterator, JSStringIterator::kNextIndexOffset,
index);
Return(iterator);
}
// Return the |word32| codepoint at {index}. Supports SeqStrings and
// ExternalStrings.
TNode<Int32T> StringBuiltinsAssembler::LoadSurrogatePairAt(
SloppyTNode<String> string, SloppyTNode<IntPtrT> length,
SloppyTNode<IntPtrT> index, UnicodeEncoding encoding) {
Label handle_surrogate_pair(this), return_result(this);
TVARIABLE(Int32T, var_result);
TVARIABLE(Int32T, var_trail);
var_result = StringCharCodeAt(string, index);
var_trail = Int32Constant(0);
GotoIf(Word32NotEqual(Word32And(var_result, Int32Constant(0xFC00)),
Int32Constant(0xD800)),
&return_result);
TNode<IntPtrT> next_index = IntPtrAdd(index, IntPtrConstant(1));
GotoIfNot(IntPtrLessThan(next_index, length), &return_result);
var_trail = StringCharCodeAt(string, next_index);
Branch(Word32Equal(Word32And(var_trail, Int32Constant(0xFC00)),
Int32Constant(0xDC00)),
&handle_surrogate_pair, &return_result);
BIND(&handle_surrogate_pair);
{
TNode<Int32T> lead = var_result;
TNode<Int32T> trail = var_trail;
// Check that this path is only taken if a surrogate pair is found
CSA_SLOW_ASSERT(this,
Uint32GreaterThanOrEqual(lead, Int32Constant(0xD800)));
CSA_SLOW_ASSERT(this, Uint32LessThan(lead, Int32Constant(0xDC00)));
CSA_SLOW_ASSERT(this,
Uint32GreaterThanOrEqual(trail, Int32Constant(0xDC00)));
CSA_SLOW_ASSERT(this, Uint32LessThan(trail, Int32Constant(0xE000)));
switch (encoding) {
case UnicodeEncoding::UTF16:
var_result = Signed(Word32Or(
// Need to swap the order for big-endian platforms
#if V8_TARGET_BIG_ENDIAN
Word32Shl(lead, Int32Constant(16)), trail));
#else
Word32Shl(trail, Int32Constant(16)), lead));
#endif
break;
case UnicodeEncoding::UTF32: {
// Convert UTF16 surrogate pair into |word32| code point, encoded as
// UTF32.
TNode<Int32T> surrogate_offset =
Int32Constant(0x10000 - (0xD800 << 10) - 0xDC00);
// (lead << 10) + trail + SURROGATE_OFFSET
var_result = Signed(Int32Add(Word32Shl(lead, Int32Constant(10)),
Int32Add(trail, surrogate_offset)));
break;
}
}
Goto(&return_result);
}
BIND(&return_result);
return var_result;
}
// ES6 #sec-%stringiteratorprototype%.next
TF_BUILTIN(StringIteratorPrototypeNext, StringBuiltinsAssembler) {
VARIABLE(var_value, MachineRepresentation::kTagged);
VARIABLE(var_done, MachineRepresentation::kTagged);
var_value.Bind(UndefinedConstant());
var_done.Bind(TrueConstant());
Label throw_bad_receiver(this), next_codepoint(this), return_result(this);
Node* context = Parameter(Descriptor::kContext);
Node* iterator = Parameter(Descriptor::kReceiver);
GotoIf(TaggedIsSmi(iterator), &throw_bad_receiver);
GotoIfNot(
InstanceTypeEqual(LoadInstanceType(iterator), JS_STRING_ITERATOR_TYPE),
&throw_bad_receiver);
Node* string = LoadObjectField(iterator, JSStringIterator::kStringOffset);
TNode<IntPtrT> position = SmiUntag(
CAST(LoadObjectField(iterator, JSStringIterator::kNextIndexOffset)));
TNode<IntPtrT> length = LoadStringLengthAsWord(string);
Branch(IntPtrLessThan(position, length), &next_codepoint, &return_result);
BIND(&next_codepoint);
{
UnicodeEncoding encoding = UnicodeEncoding::UTF16;
TNode<Int32T> ch = LoadSurrogatePairAt(string, length, position, encoding);
TNode<String> value = StringFromCodePoint(ch, encoding);
var_value.Bind(value);
TNode<IntPtrT> length = LoadStringLengthAsWord(value);
StoreObjectFieldNoWriteBarrier(iterator, JSStringIterator::kNextIndexOffset,
SmiTag(Signed(IntPtrAdd(position, length))));
var_done.Bind(FalseConstant());
Goto(&return_result);
}
BIND(&return_result);
{
Node* result =
AllocateJSIteratorResult(context, var_value.value(), var_done.value());
Return(result);
}
BIND(&throw_bad_receiver);
{
// The {receiver} is not a valid JSGeneratorObject.
CallRuntime(Runtime::kThrowIncompatibleMethodReceiver, context,
StringConstant("String Iterator.prototype.next"), iterator);
Unreachable();
}
}
// -----------------------------------------------------------------------------
// ES6 section B.2.3 Additional Properties of the String.prototype object
class StringHtmlAssembler : public StringBuiltinsAssembler {
public:
explicit StringHtmlAssembler(compiler::CodeAssemblerState* state)
: StringBuiltinsAssembler(state) {}
protected:
void Generate(Node* const context, Node* const receiver,
const char* method_name, const char* tag_name) {
Node* const string = ToThisString(context, receiver, method_name);
std::string open_tag = "<" + std::string(tag_name) + ">";
std::string close_tag = "</" + std::string(tag_name) + ">";
Node* strings[] = {StringConstant(open_tag.c_str()), string,
StringConstant(close_tag.c_str())};
Return(ConcatStrings(context, strings, arraysize(strings)));
}
void GenerateWithAttribute(Node* const context, Node* const receiver,
const char* method_name, const char* tag_name,
const char* attr, Node* const value) {
Node* const string = ToThisString(context, receiver, method_name);
Node* const value_string =
EscapeQuotes(context, ToString_Inline(context, value));
std::string open_tag_attr =
"<" + std::string(tag_name) + " " + std::string(attr) + "=\"";
std::string close_tag = "</" + std::string(tag_name) + ">";
Node* strings[] = {StringConstant(open_tag_attr.c_str()), value_string,
StringConstant("\">"), string,
StringConstant(close_tag.c_str())};
Return(ConcatStrings(context, strings, arraysize(strings)));
}
Node* ConcatStrings(Node* const context, Node** strings, int len) {
VARIABLE(var_result, MachineRepresentation::kTagged, strings[0]);
for (int i = 1; i < len; i++) {
var_result.Bind(CallStub(CodeFactory::StringAdd(isolate()), context,
var_result.value(), strings[i]));
}
return var_result.value();
}
Node* EscapeQuotes(Node* const context, Node* const string) {
CSA_ASSERT(this, IsString(string));
Node* const regexp_function = LoadContextElement(
LoadNativeContext(context), Context::REGEXP_FUNCTION_INDEX);
Node* const initial_map = LoadObjectField(
regexp_function, JSFunction::kPrototypeOrInitialMapOffset);
// TODO(pwong): Refactor to not allocate RegExp
Node* const regexp =
CallRuntime(Runtime::kRegExpInitializeAndCompile, context,
AllocateJSObjectFromMap(initial_map), StringConstant("\""),
StringConstant("g"));
return CallRuntime(Runtime::kRegExpInternalReplace, context, regexp, string,
StringConstant("&quot;"));
}
};
// ES6 #sec-string.prototype.anchor
TF_BUILTIN(StringPrototypeAnchor, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Node* const value = Parameter(Descriptor::kValue);
GenerateWithAttribute(context, receiver, "String.prototype.anchor", "a",
"name", value);
}
// ES6 #sec-string.prototype.big
TF_BUILTIN(StringPrototypeBig, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.big", "big");
}
// ES6 #sec-string.prototype.blink
TF_BUILTIN(StringPrototypeBlink, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.blink", "blink");
}
// ES6 #sec-string.prototype.bold
TF_BUILTIN(StringPrototypeBold, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.bold", "b");
}
// ES6 #sec-string.prototype.fontcolor
TF_BUILTIN(StringPrototypeFontcolor, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Node* const value = Parameter(Descriptor::kValue);
GenerateWithAttribute(context, receiver, "String.prototype.fontcolor", "font",
"color", value);
}
// ES6 #sec-string.prototype.fontsize
TF_BUILTIN(StringPrototypeFontsize, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Node* const value = Parameter(Descriptor::kValue);
GenerateWithAttribute(context, receiver, "String.prototype.fontsize", "font",
"size", value);
}
// ES6 #sec-string.prototype.fixed
TF_BUILTIN(StringPrototypeFixed, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.fixed", "tt");
}
// ES6 #sec-string.prototype.italics
TF_BUILTIN(StringPrototypeItalics, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.italics", "i");
}
// ES6 #sec-string.prototype.link
TF_BUILTIN(StringPrototypeLink, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Node* const value = Parameter(Descriptor::kValue);
GenerateWithAttribute(context, receiver, "String.prototype.link", "a", "href",
value);
}
// ES6 #sec-string.prototype.small
TF_BUILTIN(StringPrototypeSmall, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.small", "small");
}
// ES6 #sec-string.prototype.strike
TF_BUILTIN(StringPrototypeStrike, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.strike", "strike");
}
// ES6 #sec-string.prototype.sub
TF_BUILTIN(StringPrototypeSub, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.sub", "sub");
}
// ES6 #sec-string.prototype.sup
TF_BUILTIN(StringPrototypeSup, StringHtmlAssembler) {
Node* const context = Parameter(Descriptor::kContext);
Node* const receiver = Parameter(Descriptor::kReceiver);
Generate(context, receiver, "String.prototype.sup", "sup");
}
} // namespace internal
} // namespace v8