blob: 873509190ccab689667ba52b266a4405b81e6c2e [file] [log] [blame]
// Copyright 2019 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/parsing/literal-buffer.h"
#include "src/heap/factory.h"
#include "src/isolate.h"
#include "src/memcopy.h"
namespace v8 {
namespace internal {
Handle<String> LiteralBuffer::Internalize(Isolate* isolate) const {
if (is_one_byte()) {
return isolate->factory()->InternalizeOneByteString(one_byte_literal());
}
return isolate->factory()->InternalizeTwoByteString(two_byte_literal());
}
int LiteralBuffer::NewCapacity(int min_capacity) {
return min_capacity < (kMaxGrowth / (kGrowthFactor - 1))
? min_capacity * kGrowthFactor
: min_capacity + kMaxGrowth;
}
void LiteralBuffer::ExpandBuffer() {
int min_capacity = Max(kInitialCapacity, backing_store_.length());
Vector<byte> new_store = Vector<byte>::New(NewCapacity(min_capacity));
if (position_ > 0) {
MemCopy(new_store.begin(), backing_store_.begin(), position_);
}
backing_store_.Dispose();
backing_store_ = new_store;
}
void LiteralBuffer::ConvertToTwoByte() {
DCHECK(is_one_byte());
Vector<byte> new_store;
int new_content_size = position_ * kUC16Size;
if (new_content_size >= backing_store_.length()) {
// Ensure room for all currently read code units as UC16 as well
// as the code unit about to be stored.
new_store = Vector<byte>::New(NewCapacity(new_content_size));
} else {
new_store = backing_store_;
}
uint8_t* src = backing_store_.begin();
uint16_t* dst = reinterpret_cast<uint16_t*>(new_store.begin());
for (int i = position_ - 1; i >= 0; i--) {
dst[i] = src[i];
}
if (new_store.begin() != backing_store_.begin()) {
backing_store_.Dispose();
backing_store_ = new_store;
}
position_ = new_content_size;
is_one_byte_ = false;
}
void LiteralBuffer::AddTwoByteChar(uc32 code_unit) {
DCHECK(!is_one_byte());
if (position_ >= backing_store_.length()) ExpandBuffer();
if (code_unit <=
static_cast<uc32>(unibrow::Utf16::kMaxNonSurrogateCharCode)) {
*reinterpret_cast<uint16_t*>(&backing_store_[position_]) = code_unit;
position_ += kUC16Size;
} else {
*reinterpret_cast<uint16_t*>(&backing_store_[position_]) =
unibrow::Utf16::LeadSurrogate(code_unit);
position_ += kUC16Size;
if (position_ >= backing_store_.length()) ExpandBuffer();
*reinterpret_cast<uint16_t*>(&backing_store_[position_]) =
unibrow::Utf16::TrailSurrogate(code_unit);
position_ += kUC16Size;
}
}
} // namespace internal
} // namespace v8