// Copyright 2012 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/ast/ast-numbering.h"
#include "src/ast/ast.h"
#include "src/ast/scopes.h"
#include "src/compiler.h"
#include "src/objects-inl.h"
namespace v8 {
namespace internal {
class AstNumberingVisitor final : public AstVisitor<AstNumberingVisitor> {
public:
AstNumberingVisitor(uintptr_t stack_limit, Zone* zone,
Compiler::EagerInnerFunctionLiterals* eager_literals)
: zone_(zone),
eager_literals_(eager_literals),
next_id_(BailoutId::FirstUsable().ToInt()),
yield_count_(0),
properties_(zone),
language_mode_(SLOPPY),
slot_cache_(zone),
disable_crankshaft_reason_(kNoReason),
dont_optimize_reason_(kNoReason),
catch_prediction_(HandlerTable::UNCAUGHT) {
InitializeAstVisitor(stack_limit);
}
bool Renumber(FunctionLiteral* node);
private:
// AST node visitor interface.
#define DEFINE_VISIT(type) void Visit##type(type* node);
AST_NODE_LIST(DEFINE_VISIT)
#undef DEFINE_VISIT
void VisitVariableProxy(VariableProxy* node, TypeofMode typeof_mode);
void VisitVariableProxyReference(VariableProxy* node);
void VisitPropertyReference(Property* node);
void VisitReference(Expression* expr);
void VisitStatementsAndDeclarations(Block* node);
void VisitStatements(ZoneList<Statement*>* statements);
void VisitDeclarations(Declaration::List* declarations);
void VisitArguments(ZoneList<Expression*>* arguments);
void VisitLiteralProperty(LiteralProperty* property);
int ReserveIdRange(int n) {
int tmp = next_id_;
next_id_ += n;
return tmp;
}
void IncrementNodeCount() { properties_.add_node_count(1); }
void DisableSelfOptimization() {
properties_.flags() |= AstProperties::kDontSelfOptimize;
}
void DisableOptimization(BailoutReason reason) {
dont_optimize_reason_ = reason;
DisableSelfOptimization();
}
void DisableFullCodegenAndCrankshaft(BailoutReason reason) {
disable_crankshaft_reason_ = reason;
properties_.flags() |= AstProperties::kMustUseIgnitionTurbo;
}
template <typename Node>
void ReserveFeedbackSlots(Node* node) {
node->AssignFeedbackSlots(properties_.get_spec(), language_mode_,
&slot_cache_);
}
class LanguageModeScope {
public:
LanguageModeScope(AstNumberingVisitor* visitor, LanguageMode language_mode)
: visitor_(visitor), outer_language_mode_(visitor->language_mode_) {
visitor_->language_mode_ = language_mode;
}
~LanguageModeScope() { visitor_->language_mode_ = outer_language_mode_; }
private:
AstNumberingVisitor* visitor_;
LanguageMode outer_language_mode_;
};
BailoutReason dont_optimize_reason() const { return dont_optimize_reason_; }
Zone* zone() const { return zone_; }
Zone* zone_;
Compiler::EagerInnerFunctionLiterals* eager_literals_;
int next_id_;
int yield_count_;
AstProperties properties_;
LanguageMode language_mode_;
// The slot cache allows us to reuse certain feedback slots.
FeedbackSlotCache slot_cache_;
BailoutReason disable_crankshaft_reason_;
BailoutReason dont_optimize_reason_;
HandlerTable::CatchPrediction catch_prediction_;
DEFINE_AST_VISITOR_SUBCLASS_MEMBERS();
DISALLOW_COPY_AND_ASSIGN(AstNumberingVisitor);
};
void AstNumberingVisitor::VisitVariableDeclaration(VariableDeclaration* node) {
IncrementNodeCount();
VisitVariableProxy(node->proxy());
}
void AstNumberingVisitor::VisitEmptyStatement(EmptyStatement* node) {
IncrementNodeCount();
}
void AstNumberingVisitor::VisitSloppyBlockFunctionStatement(
SloppyBlockFunctionStatement* node) {
IncrementNodeCount();
Visit(node->statement());
}
void AstNumberingVisitor::VisitContinueStatement(ContinueStatement* node) {
IncrementNodeCount();
}
void AstNumberingVisitor::VisitBreakStatement(BreakStatement* node) {
IncrementNodeCount();
}
void AstNumberingVisitor::VisitDebuggerStatement(DebuggerStatement* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kDebuggerStatement);
}
void AstNumberingVisitor::VisitNativeFunctionLiteral(
NativeFunctionLiteral* node) {
IncrementNodeCount();
DisableOptimization(kNativeFunctionLiteral);
node->set_base_id(ReserveIdRange(NativeFunctionLiteral::num_ids()));
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitDoExpression(DoExpression* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(DoExpression::num_ids()));
Visit(node->block());
Visit(node->result());
}
void AstNumberingVisitor::VisitLiteral(Literal* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(Literal::num_ids()));
}
void AstNumberingVisitor::VisitRegExpLiteral(RegExpLiteral* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(RegExpLiteral::num_ids()));
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitVariableProxyReference(VariableProxy* node) {
IncrementNodeCount();
switch (node->var()->location()) {
case VariableLocation::LOOKUP:
DisableFullCodegenAndCrankshaft(
kReferenceToAVariableWhichRequiresDynamicLookup);
break;
case VariableLocation::MODULE:
DisableFullCodegenAndCrankshaft(kReferenceToModuleVariable);
break;
default:
break;
}
node->set_base_id(ReserveIdRange(VariableProxy::num_ids()));
}
void AstNumberingVisitor::VisitVariableProxy(VariableProxy* node,
TypeofMode typeof_mode) {
VisitVariableProxyReference(node);
node->AssignFeedbackSlots(properties_.get_spec(), typeof_mode, &slot_cache_);
}
void AstNumberingVisitor::VisitVariableProxy(VariableProxy* node) {
VisitVariableProxy(node, NOT_INSIDE_TYPEOF);
}
void AstNumberingVisitor::VisitThisFunction(ThisFunction* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(ThisFunction::num_ids()));
}
void AstNumberingVisitor::VisitSuperPropertyReference(
SuperPropertyReference* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kSuperReference);
node->set_base_id(ReserveIdRange(SuperPropertyReference::num_ids()));
Visit(node->this_var());
Visit(node->home_object());
}
void AstNumberingVisitor::VisitSuperCallReference(SuperCallReference* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kSuperReference);
node->set_base_id(ReserveIdRange(SuperCallReference::num_ids()));
Visit(node->this_var());
Visit(node->new_target_var());
Visit(node->this_function_var());
}
void AstNumberingVisitor::VisitExpressionStatement(ExpressionStatement* node) {
IncrementNodeCount();
Visit(node->expression());
}
void AstNumberingVisitor::VisitReturnStatement(ReturnStatement* node) {
IncrementNodeCount();
Visit(node->expression());
DCHECK(!node->is_async_return() ||
properties_.flags() & AstProperties::kMustUseIgnitionTurbo);
}
void AstNumberingVisitor::VisitYield(Yield* node) {
node->set_yield_id(yield_count_);
yield_count_++;
IncrementNodeCount();
node->set_base_id(ReserveIdRange(Yield::num_ids()));
Visit(node->generator_object());
Visit(node->expression());
}
void AstNumberingVisitor::VisitThrow(Throw* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(Throw::num_ids()));
Visit(node->exception());
}
void AstNumberingVisitor::VisitUnaryOperation(UnaryOperation* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(UnaryOperation::num_ids()));
if ((node->op() == Token::TYPEOF) && node->expression()->IsVariableProxy()) {
VariableProxy* proxy = node->expression()->AsVariableProxy();
VisitVariableProxy(proxy, INSIDE_TYPEOF);
} else {
Visit(node->expression());
}
}
void AstNumberingVisitor::VisitCountOperation(CountOperation* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(CountOperation::num_ids()));
Visit(node->expression());
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitBlock(Block* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(Block::num_ids()));
Scope* scope = node->scope();
if (scope != nullptr) {
LanguageModeScope language_mode_scope(this, scope->language_mode());
VisitStatementsAndDeclarations(node);
} else {
VisitStatementsAndDeclarations(node);
}
}
void AstNumberingVisitor::VisitStatementsAndDeclarations(Block* node) {
Scope* scope = node->scope();
DCHECK(scope == nullptr || !scope->HasBeenRemoved());
if (scope) VisitDeclarations(scope->declarations());
VisitStatements(node->statements());
}
void AstNumberingVisitor::VisitFunctionDeclaration(FunctionDeclaration* node) {
IncrementNodeCount();
VisitVariableProxy(node->proxy());
VisitFunctionLiteral(node->fun());
}
void AstNumberingVisitor::VisitCallRuntime(CallRuntime* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(CallRuntime::num_ids()));
VisitArguments(node->arguments());
// To support catch prediction within async/await:
//
// The AstNumberingVisitor is when catch prediction currently occurs, and it
// is the only common point that has access to this information. The parser
// just doesn't know yet. Take the following two cases of catch prediction:
//
// try { await fn(); } catch (e) { }
// try { await fn(); } finally { }
//
// When parsing the await that we want to mark as caught or uncaught, it's
// not yet known whether it will be followed by a 'finally' or a 'catch.
// The AstNumberingVisitor is what learns whether it is caught. To make
// the information available later to the runtime, the AstNumberingVisitor
// has to stash it somewhere. Changing the runtime function into another
// one in ast-numbering seemed like a simple and straightforward solution to
// that problem.
if (node->is_jsruntime() &&
node->context_index() == Context::ASYNC_FUNCTION_AWAIT_CAUGHT_INDEX &&
catch_prediction_ == HandlerTable::ASYNC_AWAIT) {
node->set_context_index(Context::ASYNC_FUNCTION_AWAIT_UNCAUGHT_INDEX);
}
}
void AstNumberingVisitor::VisitWithStatement(WithStatement* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kWithStatement);
Visit(node->expression());
Visit(node->statement());
}
void AstNumberingVisitor::VisitDoWhileStatement(DoWhileStatement* node) {
IncrementNodeCount();
DisableSelfOptimization();
node->set_base_id(ReserveIdRange(DoWhileStatement::num_ids()));
node->set_first_yield_id(yield_count_);
Visit(node->body());
Visit(node->cond());
node->set_yield_count(yield_count_ - node->first_yield_id());
}
void AstNumberingVisitor::VisitWhileStatement(WhileStatement* node) {
IncrementNodeCount();
DisableSelfOptimization();
node->set_base_id(ReserveIdRange(WhileStatement::num_ids()));
node->set_first_yield_id(yield_count_);
Visit(node->cond());
Visit(node->body());
node->set_yield_count(yield_count_ - node->first_yield_id());
}
void AstNumberingVisitor::VisitTryCatchStatement(TryCatchStatement* node) {
DCHECK(node->scope() == nullptr || !node->scope()->HasBeenRemoved());
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kTryCatchStatement);
{
const HandlerTable::CatchPrediction old_prediction = catch_prediction_;
// This node uses its own prediction, unless it's "uncaught", in which case
// we adopt the prediction of the outer try-block.
HandlerTable::CatchPrediction catch_prediction = node->catch_prediction();
if (catch_prediction != HandlerTable::UNCAUGHT) {
catch_prediction_ = catch_prediction;
}
node->set_catch_prediction(catch_prediction_);
Visit(node->try_block());
catch_prediction_ = old_prediction;
}
Visit(node->catch_block());
}
void AstNumberingVisitor::VisitTryFinallyStatement(TryFinallyStatement* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kTryFinallyStatement);
// We can't know whether the finally block will override ("catch") an
// exception thrown in the try block, so we just adopt the outer prediction.
node->set_catch_prediction(catch_prediction_);
Visit(node->try_block());
Visit(node->finally_block());
}
void AstNumberingVisitor::VisitPropertyReference(Property* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(Property::num_ids()));
Visit(node->key());
Visit(node->obj());
}
void AstNumberingVisitor::VisitReference(Expression* expr) {
DCHECK(expr->IsProperty() || expr->IsVariableProxy());
if (expr->IsProperty()) {
VisitPropertyReference(expr->AsProperty());
} else {
VisitVariableProxyReference(expr->AsVariableProxy());
}
}
void AstNumberingVisitor::VisitProperty(Property* node) {
VisitPropertyReference(node);
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitAssignment(Assignment* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(Assignment::num_ids()));
if (node->is_compound()) VisitBinaryOperation(node->binary_operation());
VisitReference(node->target());
Visit(node->value());
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitBinaryOperation(BinaryOperation* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(BinaryOperation::num_ids()));
Visit(node->left());
Visit(node->right());
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitCompareOperation(CompareOperation* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(CompareOperation::num_ids()));
Visit(node->left());
Visit(node->right());
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitSpread(Spread* node) {
IncrementNodeCount();
// We can only get here from spread calls currently.
DisableFullCodegenAndCrankshaft(kSpreadCall);
node->set_base_id(ReserveIdRange(Spread::num_ids()));
Visit(node->expression());
}
void AstNumberingVisitor::VisitEmptyParentheses(EmptyParentheses* node) {
UNREACHABLE();
}
void AstNumberingVisitor::VisitGetIterator(GetIterator* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kGetIterator);
node->set_base_id(ReserveIdRange(GetIterator::num_ids()));
Visit(node->iterable());
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitForInStatement(ForInStatement* node) {
IncrementNodeCount();
DisableSelfOptimization();
node->set_base_id(ReserveIdRange(ForInStatement::num_ids()));
Visit(node->enumerable()); // Not part of loop.
node->set_first_yield_id(yield_count_);
Visit(node->each());
Visit(node->body());
node->set_yield_count(yield_count_ - node->first_yield_id());
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitForOfStatement(ForOfStatement* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kForOfStatement);
node->set_base_id(ReserveIdRange(ForOfStatement::num_ids()));
Visit(node->assign_iterator()); // Not part of loop.
node->set_first_yield_id(yield_count_);
Visit(node->next_result());
Visit(node->result_done());
Visit(node->assign_each());
Visit(node->body());
node->set_yield_count(yield_count_ - node->first_yield_id());
}
void AstNumberingVisitor::VisitConditional(Conditional* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(Conditional::num_ids()));
Visit(node->condition());
Visit(node->then_expression());
Visit(node->else_expression());
}
void AstNumberingVisitor::VisitIfStatement(IfStatement* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(IfStatement::num_ids()));
Visit(node->condition());
Visit(node->then_statement());
if (node->HasElseStatement()) {
Visit(node->else_statement());
}
}
void AstNumberingVisitor::VisitSwitchStatement(SwitchStatement* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(SwitchStatement::num_ids()));
Visit(node->tag());
ZoneList<CaseClause*>* cases = node->cases();
for (int i = 0; i < cases->length(); i++) {
VisitCaseClause(cases->at(i));
}
}
void AstNumberingVisitor::VisitCaseClause(CaseClause* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(CaseClause::num_ids()));
if (!node->is_default()) Visit(node->label());
VisitStatements(node->statements());
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitForStatement(ForStatement* node) {
IncrementNodeCount();
DisableSelfOptimization();
node->set_base_id(ReserveIdRange(ForStatement::num_ids()));
if (node->init() != NULL) Visit(node->init()); // Not part of loop.
node->set_first_yield_id(yield_count_);
if (node->cond() != NULL) Visit(node->cond());
if (node->next() != NULL) Visit(node->next());
Visit(node->body());
node->set_yield_count(yield_count_ - node->first_yield_id());
}
void AstNumberingVisitor::VisitClassLiteral(ClassLiteral* node) {
IncrementNodeCount();
DisableFullCodegenAndCrankshaft(kClassLiteral);
node->set_base_id(ReserveIdRange(ClassLiteral::num_ids()));
if (node->extends()) Visit(node->extends());
if (node->constructor()) Visit(node->constructor());
if (node->class_variable_proxy()) {
VisitVariableProxy(node->class_variable_proxy());
}
for (int i = 0; i < node->properties()->length(); i++) {
VisitLiteralProperty(node->properties()->at(i));
}
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitObjectLiteral(ObjectLiteral* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(node->num_ids()));
for (int i = 0; i < node->properties()->length(); i++) {
VisitLiteralProperty(node->properties()->at(i));
}
node->InitDepthAndFlags();
// Mark all computed expressions that are bound to a key that
// is shadowed by a later occurrence of the same key. For the
// marked expressions, no store code will be is emitted.
node->CalculateEmitStore(zone_);
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitLiteralProperty(LiteralProperty* node) {
if (node->is_computed_name())
DisableFullCodegenAndCrankshaft(kComputedPropertyName);
Visit(node->key());
Visit(node->value());
}
void AstNumberingVisitor::VisitArrayLiteral(ArrayLiteral* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(node->num_ids()));
for (int i = 0; i < node->values()->length(); i++) {
Visit(node->values()->at(i));
}
node->InitDepthAndFlags();
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitCall(Call* node) {
if (node->is_possibly_eval()) {
DisableFullCodegenAndCrankshaft(kFunctionCallsEval);
}
IncrementNodeCount();
ReserveFeedbackSlots(node);
node->set_base_id(ReserveIdRange(Call::num_ids()));
Visit(node->expression());
VisitArguments(node->arguments());
}
void AstNumberingVisitor::VisitCallNew(CallNew* node) {
IncrementNodeCount();
ReserveFeedbackSlots(node);
node->set_base_id(ReserveIdRange(CallNew::num_ids()));
Visit(node->expression());
VisitArguments(node->arguments());
}
void AstNumberingVisitor::VisitStatements(ZoneList<Statement*>* statements) {
if (statements == NULL) return;
for (int i = 0; i < statements->length(); i++) {
Visit(statements->at(i));
}
}
void AstNumberingVisitor::VisitDeclarations(Declaration::List* decls) {
for (Declaration* decl : *decls) Visit(decl);
}
void AstNumberingVisitor::VisitArguments(ZoneList<Expression*>* arguments) {
for (int i = 0; i < arguments->length(); i++) {
Visit(arguments->at(i));
}
}
void AstNumberingVisitor::VisitFunctionLiteral(FunctionLiteral* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(FunctionLiteral::num_ids()));
if (node->ShouldEagerCompile()) {
if (eager_literals_) {
eager_literals_->Add(new (zone())
ThreadedListZoneEntry<FunctionLiteral*>(node));
}
// If the function literal is being eagerly compiled, recurse into the
// declarations and body of the function literal.
if (!AstNumbering::Renumber(stack_limit_, zone_, node, eager_literals_)) {
SetStackOverflow();
return;
}
}
ReserveFeedbackSlots(node);
}
void AstNumberingVisitor::VisitRewritableExpression(
RewritableExpression* node) {
IncrementNodeCount();
node->set_base_id(ReserveIdRange(RewritableExpression::num_ids()));
Visit(node->expression());
}
bool AstNumberingVisitor::Renumber(FunctionLiteral* node) {
DeclarationScope* scope = node->scope();
DCHECK(!scope->HasBeenRemoved());
if (scope->new_target_var() != nullptr ||
scope->this_function_var() != nullptr) {
DisableFullCodegenAndCrankshaft(kSuperReference);
}
if (scope->arguments() != nullptr &&
!scope->arguments()->IsStackAllocated()) {
DisableFullCodegenAndCrankshaft(kContextAllocatedArguments);
}
if (scope->rest_parameter() != nullptr) {
DisableFullCodegenAndCrankshaft(kRestParameter);
}
if (IsResumableFunction(node->kind())) {
DisableFullCodegenAndCrankshaft(kGenerator);
}
if (IsClassConstructor(node->kind())) {
DisableFullCodegenAndCrankshaft(kClassConstructorFunction);
}
LanguageModeScope language_mode_scope(this, node->language_mode());
VisitDeclarations(scope->declarations());
VisitStatements(node->body());
node->set_ast_properties(&properties_);
node->set_dont_optimize_reason(dont_optimize_reason());
node->set_yield_count(yield_count_);
if (FLAG_trace_opt) {
if (disable_crankshaft_reason_ != kNoReason) {
// TODO(leszeks): This is a quick'n'dirty fix to allow the debug name of
// the function to be accessed in the below print. This DCHECK will fail
// if we move ast numbering off the main thread, but that won't be before
// we remove FCG, in which case this entire check isn't necessary anyway.
AllowHandleDereference allow_deref;
DCHECK(!node->debug_name().is_null());
PrintF("[enforcing Ignition and TurboFan for %s because: %s\n",
node->debug_name()->ToCString().get(),
GetBailoutReason(disable_crankshaft_reason_));
}
}
return !HasStackOverflow();
}
bool AstNumbering::Renumber(
uintptr_t stack_limit, Zone* zone, FunctionLiteral* function,
Compiler::EagerInnerFunctionLiterals* eager_literals) {
DisallowHeapAllocation no_allocation;
DisallowHandleAllocation no_handles;
DisallowHandleDereference no_deref;
AstNumberingVisitor visitor(stack_limit, zone, eager_literals);
return visitor.Renumber(function);
}
} // namespace internal
} // namespace v8