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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"
#include "src/objects-inl.h"
namespace v8 {
namespace internal {
namespace interpreter {
BreakableControlFlowBuilder::~BreakableControlFlowBuilder() {
BindBreakTarget();
DCHECK(break_labels_.empty() || break_labels_.is_bound());
if (block_coverage_builder_ != nullptr && needs_continuation_counter()) {
block_coverage_builder_->IncrementBlockCounter(
node_, SourceRangeKind::kContinuation);
}
}
void BreakableControlFlowBuilder::BindBreakTarget() {
break_labels_.Bind(builder());
}
void BreakableControlFlowBuilder::EmitJump(BytecodeLabels* sites) {
builder()->Jump(sites->New());
}
void BreakableControlFlowBuilder::EmitJumpIfTrue(
BytecodeArrayBuilder::ToBooleanMode mode, BytecodeLabels* sites) {
builder()->JumpIfTrue(mode, sites->New());
}
void BreakableControlFlowBuilder::EmitJumpIfFalse(
BytecodeArrayBuilder::ToBooleanMode mode, BytecodeLabels* sites) {
builder()->JumpIfFalse(mode, sites->New());
}
void BreakableControlFlowBuilder::EmitJumpIfUndefined(BytecodeLabels* sites) {
builder()->JumpIfUndefined(sites->New());
}
void BreakableControlFlowBuilder::EmitJumpIfNull(BytecodeLabels* sites) {
builder()->JumpIfNull(sites->New());
}
LoopBuilder::~LoopBuilder() {
DCHECK(continue_labels_.empty() || continue_labels_.is_bound());
// Restore the parent jump table.
if (generator_jump_table_location_ != nullptr) {
*generator_jump_table_location_ = parent_generator_jump_table_;
}
}
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_labels_.empty() && continue_labels_.empty());
builder()->Bind(&loop_header_);
}
void LoopBuilder::LoopHeaderInGenerator(
BytecodeJumpTable** generator_jump_table, int first_resume_id,
int resume_count) {
// Bind all the resume points that are inside the loop to be at the loop
// header.
for (int id = first_resume_id; id < first_resume_id + resume_count; ++id) {
builder()->Bind(*generator_jump_table, id);
}
// Create the loop header.
LoopHeader();
// Create a new jump table for after the loop header for only these
// resume points.
generator_jump_table_location_ = generator_jump_table;
parent_generator_jump_table_ = *generator_jump_table;
*generator_jump_table =
builder()->AllocateJumpTable(resume_count, first_resume_id);
}
void LoopBuilder::LoopBody() {
if (block_coverage_builder_ != nullptr) {
block_coverage_builder_->IncrementBlockCounter(block_coverage_body_slot_);
}
}
void LoopBuilder::JumpToHeader(int loop_depth) {
// Pass the proper loop nesting level to the backwards branch, to trigger
// on-stack replacement when armed for the given loop nesting depth.
int level = Min(loop_depth, AbstractCode::kMaxLoopNestingMarker - 1);
// 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()->JumpLoop(&loop_header_, level);
}
void LoopBuilder::BindContinueTarget() { continue_labels_.Bind(builder()); }
SwitchBuilder::~SwitchBuilder() {
#ifdef DEBUG
for (auto site : case_sites_) {
DCHECK(site.is_bound());
}
#endif
}
void SwitchBuilder::SetCaseTarget(int index, CaseClause* clause) {
BytecodeLabel& site = case_sites_.at(index);
builder()->Bind(&site);
if (block_coverage_builder_) {
block_coverage_builder_->IncrementBlockCounter(clause,
SourceRangeKind::kBody);
}
}
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_, catch_prediction_);
}
void TryCatchBuilder::EndCatch() { builder()->Bind(&exit_); }
void TryFinallyBuilder::BeginTry(Register context) {
builder()->MarkTryBegin(handler_id_, context);
}
void TryFinallyBuilder::LeaveTry() {
builder()->Jump(finalization_sites_.New());
}
void TryFinallyBuilder::EndTry() {
builder()->MarkTryEnd(handler_id_);
}
void TryFinallyBuilder::BeginHandler() {
builder()->Bind(&handler_);
builder()->MarkHandler(handler_id_, catch_prediction_);
}
void TryFinallyBuilder::BeginFinally() { finalization_sites_.Bind(builder()); }
void TryFinallyBuilder::EndFinally() {
// Nothing to be done here.
}
ConditionalControlFlowBuilder::~ConditionalControlFlowBuilder() {
if (!else_labels_.is_bound()) else_labels_.Bind(builder());
end_labels_.Bind(builder());
DCHECK(end_labels_.empty() || end_labels_.is_bound());
DCHECK(then_labels_.empty() || then_labels_.is_bound());
DCHECK(else_labels_.empty() || else_labels_.is_bound());
// IfStatement requires a continuation counter, Conditional does not (as it
// can only contain expressions).
if (block_coverage_builder_ != nullptr && node_->IsIfStatement()) {
block_coverage_builder_->IncrementBlockCounter(
node_, SourceRangeKind::kContinuation);
}
}
void ConditionalControlFlowBuilder::JumpToEnd() {
DCHECK(end_labels_.empty()); // May only be called once.
builder()->Jump(end_labels_.New());
}
void ConditionalControlFlowBuilder::Then() {
then_labels()->Bind(builder());
if (block_coverage_builder_ != nullptr) {
block_coverage_builder_->IncrementBlockCounter(block_coverage_then_slot_);
}
}
void ConditionalControlFlowBuilder::Else() {
else_labels()->Bind(builder());
if (block_coverage_builder_ != nullptr) {
block_coverage_builder_->IncrementBlockCounter(block_coverage_else_slot_);
}
}
} // namespace interpreter
} // namespace internal
} // namespace v8
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