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|
// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef V8_HYDROGEN_H_
#define V8_HYDROGEN_H_
#include "v8.h"
#include "allocation.h"
#include "ast.h"
#include "compiler.h"
#include "hydrogen-instructions.h"
#include "type-info.h"
#include "zone.h"
namespace v8 {
namespace internal {
// Forward declarations.
class BitVector;
class HEnvironment;
class HGraph;
class HLoopInformation;
class HTracer;
class LAllocator;
class LChunk;
class LiveRange;
class HBasicBlock: public ZoneObject {
public:
explicit HBasicBlock(HGraph* graph);
virtual ~HBasicBlock() { }
// Simple accessors.
int block_id() const { return block_id_; }
void set_block_id(int id) { block_id_ = id; }
HGraph* graph() const { return graph_; }
const ZoneList<HPhi*>* phis() const { return &phis_; }
HInstruction* first() const { return first_; }
HInstruction* last() const { return last_; }
void set_last(HInstruction* instr) { last_ = instr; }
HInstruction* GetLastInstruction();
HControlInstruction* end() const { return end_; }
HLoopInformation* loop_information() const { return loop_information_; }
const ZoneList<HBasicBlock*>* predecessors() const { return &predecessors_; }
bool HasPredecessor() const { return predecessors_.length() > 0; }
const ZoneList<HBasicBlock*>* dominated_blocks() const {
return &dominated_blocks_;
}
const ZoneList<int>* deleted_phis() const {
return &deleted_phis_;
}
void RecordDeletedPhi(int merge_index) {
deleted_phis_.Add(merge_index);
}
HBasicBlock* dominator() const { return dominator_; }
HEnvironment* last_environment() const { return last_environment_; }
int argument_count() const { return argument_count_; }
void set_argument_count(int count) { argument_count_ = count; }
int first_instruction_index() const { return first_instruction_index_; }
void set_first_instruction_index(int index) {
first_instruction_index_ = index;
}
int last_instruction_index() const { return last_instruction_index_; }
void set_last_instruction_index(int index) {
last_instruction_index_ = index;
}
void AttachLoopInformation();
void DetachLoopInformation();
bool IsLoopHeader() const { return loop_information() != NULL; }
bool IsStartBlock() const { return block_id() == 0; }
void PostProcessLoopHeader(IterationStatement* stmt);
bool IsFinished() const { return end_ != NULL; }
void AddPhi(HPhi* phi);
void RemovePhi(HPhi* phi);
void AddInstruction(HInstruction* instr);
bool Dominates(HBasicBlock* other) const;
int LoopNestingDepth() const;
void SetInitialEnvironment(HEnvironment* env);
void ClearEnvironment() { last_environment_ = NULL; }
bool HasEnvironment() const { return last_environment_ != NULL; }
void UpdateEnvironment(HEnvironment* env) { last_environment_ = env; }
HBasicBlock* parent_loop_header() const { return parent_loop_header_; }
void set_parent_loop_header(HBasicBlock* block) {
ASSERT(parent_loop_header_ == NULL);
parent_loop_header_ = block;
}
bool HasParentLoopHeader() const { return parent_loop_header_ != NULL; }
void SetJoinId(int ast_id);
void Finish(HControlInstruction* last);
void FinishExit(HControlInstruction* instruction);
void Goto(HBasicBlock* block, bool drop_extra = false);
int PredecessorIndexOf(HBasicBlock* predecessor) const;
void AddSimulate(int ast_id) { AddInstruction(CreateSimulate(ast_id)); }
void AssignCommonDominator(HBasicBlock* other);
void FinishExitWithDeoptimization(HDeoptimize::UseEnvironment has_uses) {
FinishExit(CreateDeoptimize(has_uses));
}
// Add the inlined function exit sequence, adding an HLeaveInlined
// instruction and updating the bailout environment.
void AddLeaveInlined(HValue* return_value,
HBasicBlock* target,
bool drop_extra = false);
// If a target block is tagged as an inline function return, all
// predecessors should contain the inlined exit sequence:
//
// LeaveInlined
// Simulate (caller's environment)
// Goto (target block)
bool IsInlineReturnTarget() const { return is_inline_return_target_; }
void MarkAsInlineReturnTarget() { is_inline_return_target_ = true; }
bool IsDeoptimizing() const { return is_deoptimizing_; }
void MarkAsDeoptimizing() { is_deoptimizing_ = true; }
inline Zone* zone();
#ifdef DEBUG
void Verify();
#endif
private:
void RegisterPredecessor(HBasicBlock* pred);
void AddDominatedBlock(HBasicBlock* block);
HSimulate* CreateSimulate(int ast_id);
HDeoptimize* CreateDeoptimize(HDeoptimize::UseEnvironment has_uses);
int block_id_;
HGraph* graph_;
ZoneList<HPhi*> phis_;
HInstruction* first_;
HInstruction* last_;
HControlInstruction* end_;
HLoopInformation* loop_information_;
ZoneList<HBasicBlock*> predecessors_;
HBasicBlock* dominator_;
ZoneList<HBasicBlock*> dominated_blocks_;
HEnvironment* last_environment_;
// Outgoing parameter count at block exit, set during lithium translation.
int argument_count_;
// Instruction indices into the lithium code stream.
int first_instruction_index_;
int last_instruction_index_;
ZoneList<int> deleted_phis_;
HBasicBlock* parent_loop_header_;
bool is_inline_return_target_;
bool is_deoptimizing_;
};
class HLoopInformation: public ZoneObject {
public:
explicit HLoopInformation(HBasicBlock* loop_header)
: back_edges_(4),
loop_header_(loop_header),
blocks_(8),
stack_check_(NULL) {
blocks_.Add(loop_header);
}
virtual ~HLoopInformation() {}
const ZoneList<HBasicBlock*>* back_edges() const { return &back_edges_; }
const ZoneList<HBasicBlock*>* blocks() const { return &blocks_; }
HBasicBlock* loop_header() const { return loop_header_; }
HBasicBlock* GetLastBackEdge() const;
void RegisterBackEdge(HBasicBlock* block);
HStackCheck* stack_check() const { return stack_check_; }
void set_stack_check(HStackCheck* stack_check) {
stack_check_ = stack_check;
}
private:
void AddBlock(HBasicBlock* block);
ZoneList<HBasicBlock*> back_edges_;
HBasicBlock* loop_header_;
ZoneList<HBasicBlock*> blocks_;
HStackCheck* stack_check_;
};
class HGraph: public ZoneObject {
public:
explicit HGraph(CompilationInfo* info);
Isolate* isolate() { return isolate_; }
Zone* zone() { return isolate_->zone(); }
const ZoneList<HBasicBlock*>* blocks() const { return &blocks_; }
const ZoneList<HPhi*>* phi_list() const { return phi_list_; }
HBasicBlock* entry_block() const { return entry_block_; }
HEnvironment* start_environment() const { return start_environment_; }
void InitializeInferredTypes();
void InsertTypeConversions();
void InsertRepresentationChanges();
void MarkDeoptimizeOnUndefined();
void ComputeMinusZeroChecks();
bool ProcessArgumentsObject();
void EliminateRedundantPhis();
void EliminateUnreachablePhis();
void Canonicalize();
void OrderBlocks();
void AssignDominators();
void ReplaceCheckedValues();
void PropagateDeoptimizingMark();
// Returns false if there are phi-uses of the arguments-object
// which are not supported by the optimizing compiler.
bool CheckArgumentsPhiUses();
// Returns false if there are phi-uses of an uninitialized const
// which are not supported by the optimizing compiler.
bool CheckConstPhiUses();
void CollectPhis();
Handle<Code> Compile(CompilationInfo* info);
void set_undefined_constant(HConstant* constant) {
undefined_constant_.set(constant);
}
HConstant* GetConstantUndefined() const { return undefined_constant_.get(); }
HConstant* GetConstant1();
HConstant* GetConstantMinus1();
HConstant* GetConstantTrue();
HConstant* GetConstantFalse();
HConstant* GetConstantHole();
HBasicBlock* CreateBasicBlock();
HArgumentsObject* GetArgumentsObject() const {
return arguments_object_.get();
}
bool HasArgumentsObject() const { return arguments_object_.is_set(); }
void SetArgumentsObject(HArgumentsObject* object) {
arguments_object_.set(object);
}
int GetMaximumValueID() const { return values_.length(); }
int GetNextBlockID() { return next_block_id_++; }
int GetNextValueID(HValue* value) {
values_.Add(value);
return values_.length() - 1;
}
HValue* LookupValue(int id) const {
if (id >= 0 && id < values_.length()) return values_[id];
return NULL;
}
#ifdef DEBUG
void Verify(bool do_full_verify) const;
#endif
private:
void Postorder(HBasicBlock* block,
BitVector* visited,
ZoneList<HBasicBlock*>* order,
HBasicBlock* loop_header);
void PostorderLoopBlocks(HLoopInformation* loop,
BitVector* visited,
ZoneList<HBasicBlock*>* order,
HBasicBlock* loop_header);
HConstant* GetConstant(SetOncePointer<HConstant>* pointer,
Object* value);
void MarkAsDeoptimizingRecursively(HBasicBlock* block);
void InsertTypeConversions(HInstruction* instr);
void PropagateMinusZeroChecks(HValue* value, BitVector* visited);
void RecursivelyMarkPhiDeoptimizeOnUndefined(HPhi* phi);
void InsertRepresentationChangeForUse(HValue* value,
HValue* use_value,
int use_index,
Representation to);
void InsertRepresentationChangesForValue(HValue* value);
void InferTypes(ZoneList<HValue*>* worklist);
void InitializeInferredTypes(int from_inclusive, int to_inclusive);
void CheckForBackEdge(HBasicBlock* block, HBasicBlock* successor);
Isolate* isolate_;
int next_block_id_;
HBasicBlock* entry_block_;
HEnvironment* start_environment_;
ZoneList<HBasicBlock*> blocks_;
ZoneList<HValue*> values_;
ZoneList<HPhi*>* phi_list_;
SetOncePointer<HConstant> undefined_constant_;
SetOncePointer<HConstant> constant_1_;
SetOncePointer<HConstant> constant_minus1_;
SetOncePointer<HConstant> constant_true_;
SetOncePointer<HConstant> constant_false_;
SetOncePointer<HConstant> constant_hole_;
SetOncePointer<HArgumentsObject> arguments_object_;
DISALLOW_COPY_AND_ASSIGN(HGraph);
};
Zone* HBasicBlock::zone() { return graph_->zone(); }
class HEnvironment: public ZoneObject {
public:
HEnvironment(HEnvironment* outer,
Scope* scope,
Handle<JSFunction> closure);
// Simple accessors.
Handle<JSFunction> closure() const { return closure_; }
const ZoneList<HValue*>* values() const { return &values_; }
const ZoneList<int>* assigned_variables() const {
return &assigned_variables_;
}
int parameter_count() const { return parameter_count_; }
int specials_count() const { return specials_count_; }
int local_count() const { return local_count_; }
HEnvironment* outer() const { return outer_; }
int pop_count() const { return pop_count_; }
int push_count() const { return push_count_; }
int ast_id() const { return ast_id_; }
void set_ast_id(int id) { ast_id_ = id; }
int length() const { return values_.length(); }
bool is_special_index(int i) const {
return i >= parameter_count() && i < parameter_count() + specials_count();
}
void Bind(Variable* variable, HValue* value) {
Bind(IndexFor(variable), value);
}
void Bind(int index, HValue* value);
void BindContext(HValue* value) {
Bind(parameter_count(), value);
}
HValue* Lookup(Variable* variable) const {
return Lookup(IndexFor(variable));
}
HValue* Lookup(int index) const {
HValue* result = values_[index];
ASSERT(result != NULL);
return result;
}
HValue* LookupContext() const {
// Return first special.
return Lookup(parameter_count());
}
void Push(HValue* value) {
ASSERT(value != NULL);
++push_count_;
values_.Add(value);
}
HValue* Pop() {
ASSERT(!ExpressionStackIsEmpty());
if (push_count_ > 0) {
--push_count_;
} else {
++pop_count_;
}
return values_.RemoveLast();
}
void Drop(int count);
HValue* Top() const { return ExpressionStackAt(0); }
bool ExpressionStackIsEmpty() const;
HValue* ExpressionStackAt(int index_from_top) const {
int index = length() - index_from_top - 1;
ASSERT(HasExpressionAt(index));
return values_[index];
}
void SetExpressionStackAt(int index_from_top, HValue* value);
HEnvironment* Copy() const;
HEnvironment* CopyWithoutHistory() const;
HEnvironment* CopyAsLoopHeader(HBasicBlock* block) const;
// Create an "inlined version" of this environment, where the original
// environment is the outer environment but the top expression stack
// elements are moved to an inner environment as parameters.
HEnvironment* CopyForInlining(Handle<JSFunction> target,
FunctionLiteral* function,
HConstant* undefined,
CallKind call_kind) const;
void AddIncomingEdge(HBasicBlock* block, HEnvironment* other);
void ClearHistory() {
pop_count_ = 0;
push_count_ = 0;
assigned_variables_.Rewind(0);
}
void SetValueAt(int index, HValue* value) {
ASSERT(index < length());
values_[index] = value;
}
void PrintTo(StringStream* stream);
void PrintToStd();
private:
explicit HEnvironment(const HEnvironment* other);
// True if index is included in the expression stack part of the environment.
bool HasExpressionAt(int index) const;
void Initialize(int parameter_count, int local_count, int stack_height);
void Initialize(const HEnvironment* other);
// Map a variable to an environment index. Parameter indices are shifted
// by 1 (receiver is parameter index -1 but environment index 0).
// Stack-allocated local indices are shifted by the number of parameters.
int IndexFor(Variable* variable) const {
ASSERT(variable->IsStackAllocated());
int shift = variable->IsParameter()
? 1
: parameter_count_ + specials_count_;
return variable->index() + shift;
}
Handle<JSFunction> closure_;
// Value array [parameters] [specials] [locals] [temporaries].
ZoneList<HValue*> values_;
ZoneList<int> assigned_variables_;
int parameter_count_;
int specials_count_;
int local_count_;
HEnvironment* outer_;
int pop_count_;
int push_count_;
int ast_id_;
};
class HGraphBuilder;
enum ArgumentsAllowedFlag {
ARGUMENTS_NOT_ALLOWED,
ARGUMENTS_ALLOWED
};
// This class is not BASE_EMBEDDED because our inlining implementation uses
// new and delete.
class AstContext {
public:
bool IsEffect() const { return kind_ == Expression::kEffect; }
bool IsValue() const { return kind_ == Expression::kValue; }
bool IsTest() const { return kind_ == Expression::kTest; }
// 'Fill' this context with a hydrogen value. The value is assumed to
// have already been inserted in the instruction stream (or not need to
// be, e.g., HPhi). Call this function in tail position in the Visit
// functions for expressions.
virtual void ReturnValue(HValue* value) = 0;
// Add a hydrogen instruction to the instruction stream (recording an
// environment simulation if necessary) and then fill this context with
// the instruction as value.
virtual void ReturnInstruction(HInstruction* instr, int ast_id) = 0;
// Finishes the current basic block and materialize a boolean for
// value context, nothing for effect, generate a branch for test context.
// Call this function in tail position in the Visit functions for
// expressions.
virtual void ReturnControl(HControlInstruction* instr, int ast_id) = 0;
void set_for_typeof(bool for_typeof) { for_typeof_ = for_typeof; }
bool is_for_typeof() { return for_typeof_; }
protected:
AstContext(HGraphBuilder* owner, Expression::Context kind);
virtual ~AstContext();
HGraphBuilder* owner() const { return owner_; }
inline Zone* zone();
// We want to be able to assert, in a context-specific way, that the stack
// height makes sense when the context is filled.
#ifdef DEBUG
int original_length_;
#endif
private:
HGraphBuilder* owner_;
Expression::Context kind_;
AstContext* outer_;
bool for_typeof_;
};
class EffectContext: public AstContext {
public:
explicit EffectContext(HGraphBuilder* owner)
: AstContext(owner, Expression::kEffect) {
}
virtual ~EffectContext();
virtual void ReturnValue(HValue* value);
virtual void ReturnInstruction(HInstruction* instr, int ast_id);
virtual void ReturnControl(HControlInstruction* instr, int ast_id);
};
class ValueContext: public AstContext {
public:
explicit ValueContext(HGraphBuilder* owner, ArgumentsAllowedFlag flag)
: AstContext(owner, Expression::kValue), flag_(flag) {
}
virtual ~ValueContext();
virtual void ReturnValue(HValue* value);
virtual void ReturnInstruction(HInstruction* instr, int ast_id);
virtual void ReturnControl(HControlInstruction* instr, int ast_id);
bool arguments_allowed() { return flag_ == ARGUMENTS_ALLOWED; }
private:
ArgumentsAllowedFlag flag_;
};
class TestContext: public AstContext {
public:
TestContext(HGraphBuilder* owner,
Expression* condition,
HBasicBlock* if_true,
HBasicBlock* if_false)
: AstContext(owner, Expression::kTest),
condition_(condition),
if_true_(if_true),
if_false_(if_false) {
}
virtual void ReturnValue(HValue* value);
virtual void ReturnInstruction(HInstruction* instr, int ast_id);
virtual void ReturnControl(HControlInstruction* instr, int ast_id);
static TestContext* cast(AstContext* context) {
ASSERT(context->IsTest());
return reinterpret_cast<TestContext*>(context);
}
Expression* condition() const { return condition_; }
HBasicBlock* if_true() const { return if_true_; }
HBasicBlock* if_false() const { return if_false_; }
private:
// Build the shared core part of the translation unpacking a value into
// control flow.
void BuildBranch(HValue* value);
Expression* condition_;
HBasicBlock* if_true_;
HBasicBlock* if_false_;
};
class FunctionState {
public:
FunctionState(HGraphBuilder* owner,
CompilationInfo* info,
TypeFeedbackOracle* oracle,
bool drop_extra);
~FunctionState();
CompilationInfo* compilation_info() { return compilation_info_; }
TypeFeedbackOracle* oracle() { return oracle_; }
AstContext* call_context() { return call_context_; }
bool drop_extra() { return drop_extra_; }
HBasicBlock* function_return() { return function_return_; }
TestContext* test_context() { return test_context_; }
void ClearInlinedTestContext() {
delete test_context_;
test_context_ = NULL;
}
FunctionState* outer() { return outer_; }
private:
HGraphBuilder* owner_;
CompilationInfo* compilation_info_;
TypeFeedbackOracle* oracle_;
// During function inlining, expression context of the call being
// inlined. NULL when not inlining.
AstContext* call_context_;
// Indicate if we have to drop an extra value from the environment on
// return from inlined functions.
bool drop_extra_;
// When inlining in an effect of value context, this is the return block.
// It is NULL otherwise. When inlining in a test context, there are a
// pair of return blocks in the context. When not inlining, there is no
// local return point.
HBasicBlock* function_return_;
// When inlining a call in a test context, a context containing a pair of
// return blocks. NULL in all other cases.
TestContext* test_context_;
FunctionState* outer_;
};
class HGraphBuilder: public AstVisitor {
public:
enum BreakType { BREAK, CONTINUE };
enum SwitchType { UNKNOWN_SWITCH, SMI_SWITCH, STRING_SWITCH };
// A class encapsulating (lazily-allocated) break and continue blocks for
// a breakable statement. Separated from BreakAndContinueScope so that it
// can have a separate lifetime.
class BreakAndContinueInfo BASE_EMBEDDED {
public:
explicit BreakAndContinueInfo(BreakableStatement* target)
: target_(target), break_block_(NULL), continue_block_(NULL) {
}
BreakableStatement* target() { return target_; }
HBasicBlock* break_block() { return break_block_; }
void set_break_block(HBasicBlock* block) { break_block_ = block; }
HBasicBlock* continue_block() { return continue_block_; }
void set_continue_block(HBasicBlock* block) { continue_block_ = block; }
private:
BreakableStatement* target_;
HBasicBlock* break_block_;
HBasicBlock* continue_block_;
};
// A helper class to maintain a stack of current BreakAndContinueInfo
// structures mirroring BreakableStatement nesting.
class BreakAndContinueScope BASE_EMBEDDED {
public:
BreakAndContinueScope(BreakAndContinueInfo* info, HGraphBuilder* owner)
: info_(info), owner_(owner), next_(owner->break_scope()) {
owner->set_break_scope(this);
}
~BreakAndContinueScope() { owner_->set_break_scope(next_); }
BreakAndContinueInfo* info() { return info_; }
HGraphBuilder* owner() { return owner_; }
BreakAndContinueScope* next() { return next_; }
// Search the break stack for a break or continue target.
HBasicBlock* Get(BreakableStatement* stmt, BreakType type);
private:
BreakAndContinueInfo* info_;
HGraphBuilder* owner_;
BreakAndContinueScope* next_;
};
HGraphBuilder(CompilationInfo* info, TypeFeedbackOracle* oracle);
HGraph* CreateGraph();
// Simple accessors.
HGraph* graph() const { return graph_; }
BreakAndContinueScope* break_scope() const { return break_scope_; }
void set_break_scope(BreakAndContinueScope* head) { break_scope_ = head; }
HBasicBlock* current_block() const { return current_block_; }
void set_current_block(HBasicBlock* block) { current_block_ = block; }
HEnvironment* environment() const {
return current_block()->last_environment();
}
bool inline_bailout() { return inline_bailout_; }
// Adding instructions.
HInstruction* AddInstruction(HInstruction* instr);
void AddSimulate(int ast_id);
// Bailout environment manipulation.
void Push(HValue* value) { environment()->Push(value); }
HValue* Pop() { return environment()->Pop(); }
void Bailout(const char* reason);
HBasicBlock* CreateJoin(HBasicBlock* first,
HBasicBlock* second,
int join_id);
TypeFeedbackOracle* oracle() const { return function_state()->oracle(); }
FunctionState* function_state() const { return function_state_; }
private:
// Type of a member function that generates inline code for a native function.
typedef void (HGraphBuilder::*InlineFunctionGenerator)(CallRuntime* call);
// Forward declarations for inner scope classes.
class SubgraphScope;
static const InlineFunctionGenerator kInlineFunctionGenerators[];
static const int kMaxCallPolymorphism = 4;
static const int kMaxLoadPolymorphism = 4;
static const int kMaxStorePolymorphism = 4;
static const int kMaxInlinedNodes = 196;
static const int kMaxInlinedSize = 196;
static const int kMaxSourceSize = 600;
// Simple accessors.
void set_function_state(FunctionState* state) { function_state_ = state; }
AstContext* ast_context() const { return ast_context_; }
void set_ast_context(AstContext* context) { ast_context_ = context; }
// Accessors forwarded to the function state.
CompilationInfo* info() const {
return function_state()->compilation_info();
}
AstContext* call_context() const {
return function_state()->call_context();
}
HBasicBlock* function_return() const {
return function_state()->function_return();
}
TestContext* inlined_test_context() const {
return function_state()->test_context();
}
void ClearInlinedTestContext() {
function_state()->ClearInlinedTestContext();
}
StrictModeFlag function_strict_mode_flag() {
return function_state()->compilation_info()->is_classic_mode()
? kNonStrictMode : kStrictMode;
}
// Generators for inline runtime functions.
#define INLINE_FUNCTION_GENERATOR_DECLARATION(Name, argc, ressize) \
void Generate##Name(CallRuntime* call);
INLINE_FUNCTION_LIST(INLINE_FUNCTION_GENERATOR_DECLARATION)
INLINE_RUNTIME_FUNCTION_LIST(INLINE_FUNCTION_GENERATOR_DECLARATION)
#undef INLINE_FUNCTION_GENERATOR_DECLARATION
void HandleDeclaration(VariableProxy* proxy,
VariableMode mode,
FunctionLiteral* function);
void VisitDelete(UnaryOperation* expr);
void VisitVoid(UnaryOperation* expr);
void VisitTypeof(UnaryOperation* expr);
void VisitAdd(UnaryOperation* expr);
void VisitSub(UnaryOperation* expr);
void VisitBitNot(UnaryOperation* expr);
void VisitNot(UnaryOperation* expr);
void VisitComma(BinaryOperation* expr);
void VisitLogicalExpression(BinaryOperation* expr);
void VisitArithmeticExpression(BinaryOperation* expr);
void PreProcessOsrEntry(IterationStatement* statement);
// True iff. we are compiling for OSR and the statement is the entry.
bool HasOsrEntryAt(IterationStatement* statement);
void VisitLoopBody(IterationStatement* stmt,
HBasicBlock* loop_entry,
BreakAndContinueInfo* break_info);
// Create a back edge in the flow graph. body_exit is the predecessor
// block and loop_entry is the successor block. loop_successor is the
// block where control flow exits the loop normally (e.g., via failure of
// the condition) and break_block is the block where control flow breaks
// from the loop. All blocks except loop_entry can be NULL. The return
// value is the new successor block which is the join of loop_successor
// and break_block, or NULL.
HBasicBlock* CreateLoop(IterationStatement* statement,
HBasicBlock* loop_entry,
HBasicBlock* body_exit,
HBasicBlock* loop_successor,
HBasicBlock* break_block);
HBasicBlock* JoinContinue(IterationStatement* statement,
HBasicBlock* exit_block,
HBasicBlock* continue_block);
HValue* Top() const { return environment()->Top(); }
void Drop(int n) { environment()->Drop(n); }
void Bind(Variable* var, HValue* value) { environment()->Bind(var, value); }
// The value of the arguments object is allowed in some but not most value
// contexts. (It's allowed in all effect contexts and disallowed in all
// test contexts.)
void VisitForValue(Expression* expr,
ArgumentsAllowedFlag flag = ARGUMENTS_NOT_ALLOWED);
void VisitForTypeOf(Expression* expr);
void VisitForEffect(Expression* expr);
void VisitForControl(Expression* expr,
HBasicBlock* true_block,
HBasicBlock* false_block);
// Visit an argument subexpression and emit a push to the outgoing
// arguments. Returns the hydrogen value that was pushed.
HValue* VisitArgument(Expression* expr);
void VisitArgumentList(ZoneList<Expression*>* arguments);
// Visit a list of expressions from left to right, each in a value context.
void VisitExpressions(ZoneList<Expression*>* exprs);
void AddPhi(HPhi* phi);
void PushAndAdd(HInstruction* instr);
// Remove the arguments from the bailout environment and emit instructions
// to push them as outgoing parameters.
template <int V> HInstruction* PreProcessCall(HCall<V>* call);
void TraceRepresentation(Token::Value op,
TypeInfo info,
HValue* value,
Representation rep);
static Representation ToRepresentation(TypeInfo info);
void SetUpScope(Scope* scope);
virtual void VisitStatements(ZoneList<Statement*>* statements);
#define DECLARE_VISIT(type) virtual void Visit##type(type* node);
AST_NODE_LIST(DECLARE_VISIT)
#undef DECLARE_VISIT
HBasicBlock* CreateBasicBlock(HEnvironment* env);
HBasicBlock* CreateLoopHeaderBlock();
// Helpers for flow graph construction.
enum GlobalPropertyAccess {
kUseCell,
kUseGeneric
};
GlobalPropertyAccess LookupGlobalProperty(Variable* var,
LookupResult* lookup,
bool is_store);
bool TryArgumentsAccess(Property* expr);
// Try to optimize fun.apply(receiver, arguments) pattern.
bool TryCallApply(Call* expr);
bool TryInline(Call* expr, bool drop_extra = false);
bool TryInlineBuiltinFunction(Call* expr,
HValue* receiver,
Handle<Map> receiver_map,
CheckType check_type);
// If --trace-inlining, print a line of the inlining trace. Inlining
// succeeded if the reason string is NULL and failed if there is a
// non-NULL reason string.
void TraceInline(Handle<JSFunction> target,
Handle<JSFunction> caller,
const char* failure_reason);
void HandleGlobalVariableAssignment(Variable* var,
HValue* value,
int position,
int ast_id);
void HandlePropertyAssignment(Assignment* expr);
void HandleCompoundAssignment(Assignment* expr);
void HandlePolymorphicStoreNamedField(Assignment* expr,
HValue* object,
HValue* value,
SmallMapList* types,
Handle<String> name);
void HandlePolymorphicCallNamed(Call* expr,
HValue* receiver,
SmallMapList* types,
Handle<String> name);
void HandleLiteralCompareTypeof(CompareOperation* expr,
HTypeof* typeof_expr,
Handle<String> check);
void HandleLiteralCompareNil(CompareOperation* expr,
HValue* value,
NilValue nil);
HStringCharCodeAt* BuildStringCharCodeAt(HValue* context,
HValue* string,
HValue* index);
HInstruction* BuildBinaryOperation(BinaryOperation* expr,
HValue* left,
HValue* right);
HInstruction* BuildIncrement(bool returns_original_input,
CountOperation* expr);
HLoadNamedField* BuildLoadNamedField(HValue* object,
Property* expr,
Handle<Map> type,
LookupResult* result,
bool smi_and_map_check);
HInstruction* BuildLoadNamedGeneric(HValue* object, Property* expr);
HInstruction* BuildLoadKeyedGeneric(HValue* object,
HValue* key);
HInstruction* BuildExternalArrayElementAccess(
HValue* external_elements,
HValue* checked_key,
HValue* val,
ElementsKind elements_kind,
bool is_store);
HInstruction* BuildFastElementAccess(HValue* elements,
HValue* checked_key,
HValue* val,
ElementsKind elements_kind,
bool is_store);
HInstruction* BuildMonomorphicElementAccess(HValue* object,
HValue* key,
HValue* val,
Handle<Map> map,
bool is_store);
HValue* HandlePolymorphicElementAccess(HValue* object,
HValue* key,
HValue* val,
Expression* prop,
int ast_id,
int position,
bool is_store,
bool* has_side_effects);
HValue* HandleKeyedElementAccess(HValue* obj,
HValue* key,
HValue* val,
Expression* expr,
int ast_id,
int position,
bool is_store,
bool* has_side_effects);
HInstruction* BuildLoadNamed(HValue* object,
Property* prop,
Handle<Map> map,
Handle<String> name);
HInstruction* BuildStoreNamed(HValue* object,
HValue* value,
Expression* expr);
HInstruction* BuildStoreNamedField(HValue* object,
Handle<String> name,
HValue* value,
Handle<Map> type,
LookupResult* lookup,
bool smi_and_map_check);
HInstruction* BuildStoreNamedGeneric(HValue* object,
Handle<String> name,
HValue* value);
HInstruction* BuildStoreKeyedGeneric(HValue* object,
HValue* key,
HValue* value);
HValue* BuildContextChainWalk(Variable* var);
void AddCheckConstantFunction(Call* expr,
HValue* receiver,
Handle<Map> receiver_map,
bool smi_and_map_check);
Zone* zone() { return zone_; }
// The translation state of the currently-being-translated function.
FunctionState* function_state_;
// The base of the function state stack.
FunctionState initial_function_state_;
// Expression context of the currently visited subexpression. NULL when
// visiting statements.
AstContext* ast_context_;
// A stack of breakable statements entered.
BreakAndContinueScope* break_scope_;
HGraph* graph_;
HBasicBlock* current_block_;
int inlined_count_;
Zone* zone_;
bool inline_bailout_;
friend class FunctionState; // Pushes and pops the state stack.
friend class AstContext; // Pushes and pops the AST context stack.
DISALLOW_COPY_AND_ASSIGN(HGraphBuilder);
};
Zone* AstContext::zone() { return owner_->zone(); }
class HValueMap: public ZoneObject {
public:
HValueMap()
: array_size_(0),
lists_size_(0),
count_(0),
present_flags_(0),
array_(NULL),
lists_(NULL),
free_list_head_(kNil) {
ResizeLists(kInitialSize);
Resize(kInitialSize);
}
void Kill(GVNFlagSet flags);
void Add(HValue* value) {
present_flags_.Add(value->gvn_flags());
Insert(value);
}
HValue* Lookup(HValue* value) const;
HValueMap* Copy(Zone* zone) const {
return new(zone) HValueMap(zone, this);
}
bool IsEmpty() const { return count_ == 0; }
private:
// A linked list of HValue* values. Stored in arrays.
struct HValueMapListElement {
HValue* value;
int next; // Index in the array of the next list element.
};
static const int kNil = -1; // The end of a linked list
// Must be a power of 2.
static const int kInitialSize = 16;
HValueMap(Zone* zone, const HValueMap* other);
void Resize(int new_size);
void ResizeLists(int new_size);
void Insert(HValue* value);
uint32_t Bound(uint32_t value) const { return value & (array_size_ - 1); }
int array_size_;
int lists_size_;
int count_; // The number of values stored in the HValueMap.
GVNFlagSet present_flags_; // All flags that are in any value in the
// HValueMap.
HValueMapListElement* array_; // Primary store - contains the first value
// with a given hash. Colliding elements are stored in linked lists.
HValueMapListElement* lists_; // The linked lists containing hash collisions.
int free_list_head_; // Unused elements in lists_ are on the free list.
};
class HStatistics: public Malloced {
public:
void Initialize(CompilationInfo* info);
void Print();
void SaveTiming(const char* name, int64_t ticks, unsigned size);
static HStatistics* Instance() {
static SetOncePointer<HStatistics> instance;
if (!instance.is_set()) {
instance.set(new HStatistics());
}
return instance.get();
}
private:
HStatistics()
: timing_(5),
names_(5),
sizes_(5),
total_(0),
total_size_(0),
full_code_gen_(0),
source_size_(0) { }
List<int64_t> timing_;
List<const char*> names_;
List<unsigned> sizes_;
int64_t total_;
unsigned total_size_;
int64_t full_code_gen_;
double source_size_;
};
class HPhase BASE_EMBEDDED {
public:
static const char* const kFullCodeGen;
static const char* const kTotal;
explicit HPhase(const char* name) { Begin(name, NULL, NULL, NULL); }
HPhase(const char* name, HGraph* graph) {
Begin(name, graph, NULL, NULL);
}
HPhase(const char* name, LChunk* chunk) {
Begin(name, NULL, chunk, NULL);
}
HPhase(const char* name, LAllocator* allocator) {
Begin(name, NULL, NULL, allocator);
}
~HPhase() {
End();
}
private:
void Begin(const char* name,
HGraph* graph,
LChunk* chunk,
LAllocator* allocator);
void End() const;
int64_t start_;
const char* name_;
HGraph* graph_;
LChunk* chunk_;
LAllocator* allocator_;
unsigned start_allocation_size_;
};
class HTracer: public Malloced {
public:
void TraceCompilation(FunctionLiteral* function);
void TraceHydrogen(const char* name, HGraph* graph);
void TraceLithium(const char* name, LChunk* chunk);
void TraceLiveRanges(const char* name, LAllocator* allocator);
static HTracer* Instance() {
static SetOncePointer<HTracer> instance;
if (!instance.is_set()) {
instance.set(new HTracer("hydrogen.cfg"));
}
return instance.get();
}
private:
class Tag BASE_EMBEDDED {
public:
Tag(HTracer* tracer, const char* name) {
name_ = name;
tracer_ = tracer;
tracer->PrintIndent();
tracer->trace_.Add("begin_%s\n", name);
tracer->indent_++;
}
~Tag() {
tracer_->indent_--;
tracer_->PrintIndent();
tracer_->trace_.Add("end_%s\n", name_);
ASSERT(tracer_->indent_ >= 0);
tracer_->FlushToFile();
}
private:
HTracer* tracer_;
const char* name_;
};
explicit HTracer(const char* filename)
: filename_(filename), trace_(&string_allocator_), indent_(0) {
WriteChars(filename, "", 0, false);
}
void TraceLiveRange(LiveRange* range, const char* type);
void Trace(const char* name, HGraph* graph, LChunk* chunk);
void FlushToFile();
void PrintEmptyProperty(const char* name) {
PrintIndent();
trace_.Add("%s\n", name);
}
void PrintStringProperty(const char* name, const char* value) {
PrintIndent();
trace_.Add("%s \"%s\"\n", name, value);
}
void PrintLongProperty(const char* name, int64_t value) {
PrintIndent();
trace_.Add("%s %d000\n", name, static_cast<int>(value / 1000));
}
void PrintBlockProperty(const char* name, int block_id) {
PrintIndent();
trace_.Add("%s \"B%d\"\n", name, block_id);
}
void PrintIntProperty(const char* name, int value) {
PrintIndent();
trace_.Add("%s %d\n", name, value);
}
void PrintIndent() {
for (int i = 0; i < indent_; i++) {
trace_.Add(" ");
}
}
const char* filename_;
HeapStringAllocator string_allocator_;
StringStream trace_;
int indent_;
};
} } // namespace v8::internal
#endif // V8_HYDROGEN_H_
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