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// Copyright 2015 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/interpreter/control-flow-builders.h"
namespace v8 {
namespace internal {
namespace interpreter {
BreakableControlFlowBuilder::~BreakableControlFlowBuilder() {
DCHECK(break_sites_.empty());
}
void BreakableControlFlowBuilder::SetBreakTarget(const BytecodeLabel& target) {
BindLabels(target, &break_sites_);
}
void BreakableControlFlowBuilder::EmitJump(ZoneVector<BytecodeLabel>* sites) {
sites->push_back(BytecodeLabel());
builder()->Jump(&sites->back());
}
void BreakableControlFlowBuilder::EmitJumpIfTrue(
ZoneVector<BytecodeLabel>* sites) {
sites->push_back(BytecodeLabel());
builder()->JumpIfTrue(&sites->back());
}
void BreakableControlFlowBuilder::EmitJumpIfFalse(
ZoneVector<BytecodeLabel>* sites) {
sites->push_back(BytecodeLabel());
builder()->JumpIfFalse(&sites->back());
}
void BreakableControlFlowBuilder::EmitJumpIfUndefined(
ZoneVector<BytecodeLabel>* sites) {
sites->push_back(BytecodeLabel());
builder()->JumpIfUndefined(&sites->back());
}
void BreakableControlFlowBuilder::EmitJumpIfNull(
ZoneVector<BytecodeLabel>* sites) {
sites->push_back(BytecodeLabel());
builder()->JumpIfNull(&sites->back());
}
void BreakableControlFlowBuilder::EmitJump(ZoneVector<BytecodeLabel>* sites,
int index) {
builder()->Jump(&sites->at(index));
}
void BreakableControlFlowBuilder::EmitJumpIfTrue(
ZoneVector<BytecodeLabel>* sites, int index) {
builder()->JumpIfTrue(&sites->at(index));
}
void BreakableControlFlowBuilder::EmitJumpIfFalse(
ZoneVector<BytecodeLabel>* sites, int index) {
builder()->JumpIfFalse(&sites->at(index));
}
void BreakableControlFlowBuilder::BindLabels(const BytecodeLabel& target,
ZoneVector<BytecodeLabel>* sites) {
for (size_t i = 0; i < sites->size(); i++) {
BytecodeLabel& site = sites->at(i);
builder()->Bind(target, &site);
}
sites->clear();
}
void BlockBuilder::EndBlock() {
builder()->Bind(&block_end_);
SetBreakTarget(block_end_);
}
LoopBuilder::~LoopBuilder() { DCHECK(continue_sites_.empty()); }
void LoopBuilder::LoopHeader() {
// Jumps from before the loop header into the loop violate ordering
// requirements of bytecode basic blocks. The only entry into a loop
// must be the loop header. Surely breaks is okay? Not if nested
// and misplaced between the headers.
DCHECK(break_sites_.empty() && continue_sites_.empty());
builder()->Bind(&loop_header_);
}
void LoopBuilder::EndLoop() {
// Loop must have closed form, i.e. all loop elements are within the loop,
// the loop header precedes the body and next elements in the loop.
DCHECK(loop_header_.is_bound());
builder()->Bind(&loop_end_);
SetBreakTarget(loop_end_);
if (next_.is_bound()) {
DCHECK(!condition_.is_bound() || next_.offset() >= condition_.offset());
SetContinueTarget(next_);
} else {
DCHECK(condition_.is_bound());
DCHECK_GE(condition_.offset(), loop_header_.offset());
DCHECK_LE(condition_.offset(), loop_end_.offset());
SetContinueTarget(condition_);
}
}
void LoopBuilder::SetContinueTarget(const BytecodeLabel& target) {
BindLabels(target, &continue_sites_);
}
SwitchBuilder::~SwitchBuilder() {
#ifdef DEBUG
for (auto site : case_sites_) {
DCHECK(site.is_bound());
}
#endif
}
void SwitchBuilder::SetCaseTarget(int index) {
BytecodeLabel& site = case_sites_.at(index);
builder()->Bind(&site);
}
void TryCatchBuilder::BeginTry(Register context) {
builder()->MarkTryBegin(handler_id_, context);
}
void TryCatchBuilder::EndTry() {
builder()->MarkTryEnd(handler_id_);
builder()->Jump(&exit_);
builder()->Bind(&handler_);
builder()->MarkHandler(handler_id_, true);
}
void TryCatchBuilder::EndCatch() { builder()->Bind(&exit_); }
void TryFinallyBuilder::BeginTry(Register context) {
builder()->MarkTryBegin(handler_id_, context);
}
void TryFinallyBuilder::LeaveTry() {
finalization_sites_.push_back(BytecodeLabel());
builder()->Jump(&finalization_sites_.back());
}
void TryFinallyBuilder::EndTry() {
builder()->MarkTryEnd(handler_id_);
}
void TryFinallyBuilder::BeginHandler() {
builder()->Bind(&handler_);
builder()->MarkHandler(handler_id_, will_catch_);
}
void TryFinallyBuilder::BeginFinally() {
for (size_t i = 0; i < finalization_sites_.size(); i++) {
BytecodeLabel& site = finalization_sites_.at(i);
builder()->Bind(&site);
}
}
void TryFinallyBuilder::EndFinally() {
// Nothing to be done here.
}
} // namespace interpreter
} // namespace internal
} // namespace v8
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