| // Copyright 2014 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/compiler/js-builtin-reducer.h" |
| #include "src/compiler/js-graph.h" |
| #include "src/compiler/node-matchers.h" |
| #include "src/compiler/node-properties.h" |
| #include "src/compiler/simplified-operator.h" |
| #include "src/objects-inl.h" |
| #include "src/types.h" |
| |
| namespace v8 { |
| namespace internal { |
| namespace compiler { |
| |
| |
| // Helper class to access JSCallFunction nodes that are potential candidates |
| // for reduction when they have a BuiltinFunctionId associated with them. |
| class JSCallReduction { |
| public: |
| explicit JSCallReduction(Node* node) : node_(node) {} |
| |
| // Determines whether the node is a JSCallFunction operation that targets a |
| // constant callee being a well-known builtin with a BuiltinFunctionId. |
| bool HasBuiltinFunctionId() { |
| if (node_->opcode() != IrOpcode::kJSCallFunction) return false; |
| HeapObjectMatcher m(NodeProperties::GetValueInput(node_, 0)); |
| if (!m.HasValue() || !m.Value()->IsJSFunction()) return false; |
| Handle<JSFunction> function = Handle<JSFunction>::cast(m.Value()); |
| return function->shared()->HasBuiltinFunctionId(); |
| } |
| |
| // Retrieves the BuiltinFunctionId as described above. |
| BuiltinFunctionId GetBuiltinFunctionId() { |
| DCHECK_EQ(IrOpcode::kJSCallFunction, node_->opcode()); |
| HeapObjectMatcher m(NodeProperties::GetValueInput(node_, 0)); |
| Handle<JSFunction> function = Handle<JSFunction>::cast(m.Value()); |
| return function->shared()->builtin_function_id(); |
| } |
| |
| // Determines whether the call takes zero inputs. |
| bool InputsMatchZero() { return GetJSCallArity() == 0; } |
| |
| // Determines whether the call takes one input of the given type. |
| bool InputsMatchOne(Type* t1) { |
| return GetJSCallArity() == 1 && |
| NodeProperties::GetType(GetJSCallInput(0))->Is(t1); |
| } |
| |
| // Determines whether the call takes two inputs of the given types. |
| bool InputsMatchTwo(Type* t1, Type* t2) { |
| return GetJSCallArity() == 2 && |
| NodeProperties::GetType(GetJSCallInput(0))->Is(t1) && |
| NodeProperties::GetType(GetJSCallInput(1))->Is(t2); |
| } |
| |
| // Determines whether the call takes inputs all of the given type. |
| bool InputsMatchAll(Type* t) { |
| for (int i = 0; i < GetJSCallArity(); i++) { |
| if (!NodeProperties::GetType(GetJSCallInput(i))->Is(t)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| Node* left() { return GetJSCallInput(0); } |
| Node* right() { return GetJSCallInput(1); } |
| |
| int GetJSCallArity() { |
| DCHECK_EQ(IrOpcode::kJSCallFunction, node_->opcode()); |
| // Skip first (i.e. callee) and second (i.e. receiver) operand. |
| return node_->op()->ValueInputCount() - 2; |
| } |
| |
| Node* GetJSCallInput(int index) { |
| DCHECK_EQ(IrOpcode::kJSCallFunction, node_->opcode()); |
| DCHECK_LT(index, GetJSCallArity()); |
| // Skip first (i.e. callee) and second (i.e. receiver) operand. |
| return NodeProperties::GetValueInput(node_, index + 2); |
| } |
| |
| private: |
| Node* node_; |
| }; |
| |
| |
| JSBuiltinReducer::JSBuiltinReducer(Editor* editor, JSGraph* jsgraph) |
| : AdvancedReducer(editor), jsgraph_(jsgraph) {} |
| |
| |
| // ECMA-262, section 15.8.2.11. |
| Reduction JSBuiltinReducer::ReduceMathMax(Node* node) { |
| JSCallReduction r(node); |
| if (r.InputsMatchZero()) { |
| // Math.max() -> -Infinity |
| return Replace(jsgraph()->Constant(-V8_INFINITY)); |
| } |
| if (r.InputsMatchOne(Type::Number())) { |
| // Math.max(a:number) -> a |
| return Replace(r.left()); |
| } |
| if (r.InputsMatchAll(Type::Integral32())) { |
| // Math.max(a:int32, b:int32, ...) |
| Node* value = r.GetJSCallInput(0); |
| for (int i = 1; i < r.GetJSCallArity(); i++) { |
| Node* const input = r.GetJSCallInput(i); |
| value = graph()->NewNode( |
| common()->Select(MachineRepresentation::kNone), |
| graph()->NewNode(simplified()->NumberLessThan(), input, value), value, |
| input); |
| } |
| return Replace(value); |
| } |
| return NoChange(); |
| } |
| |
| |
| // ES6 draft 08-24-14, section 20.2.2.19. |
| Reduction JSBuiltinReducer::ReduceMathImul(Node* node) { |
| JSCallReduction r(node); |
| if (r.InputsMatchTwo(Type::Integral32(), Type::Integral32())) { |
| // Math.imul(a:int32, b:int32) -> Int32Mul(a, b) |
| Node* value = graph()->NewNode(machine()->Int32Mul(), r.left(), r.right()); |
| return Replace(value); |
| } |
| return NoChange(); |
| } |
| |
| |
| // ES6 draft 08-24-14, section 20.2.2.17. |
| Reduction JSBuiltinReducer::ReduceMathFround(Node* node) { |
| JSCallReduction r(node); |
| if (r.InputsMatchOne(Type::Number())) { |
| // Math.fround(a:number) -> TruncateFloat64ToFloat32(a) |
| Node* value = |
| graph()->NewNode(machine()->TruncateFloat64ToFloat32(), r.left()); |
| return Replace(value); |
| } |
| return NoChange(); |
| } |
| |
| |
| Reduction JSBuiltinReducer::Reduce(Node* node) { |
| Reduction reduction = NoChange(); |
| JSCallReduction r(node); |
| |
| // Dispatch according to the BuiltinFunctionId if present. |
| if (!r.HasBuiltinFunctionId()) return NoChange(); |
| switch (r.GetBuiltinFunctionId()) { |
| case kMathMax: |
| reduction = ReduceMathMax(node); |
| break; |
| case kMathImul: |
| reduction = ReduceMathImul(node); |
| break; |
| case kMathFround: |
| reduction = ReduceMathFround(node); |
| break; |
| default: |
| break; |
| } |
| |
| // Replace builtin call assuming replacement nodes are pure values that don't |
| // produce an effect. Replaces {node} with {reduction} and relaxes effects. |
| if (reduction.Changed()) ReplaceWithValue(node, reduction.replacement()); |
| |
| return reduction; |
| } |
| |
| |
| Graph* JSBuiltinReducer::graph() const { return jsgraph()->graph(); } |
| |
| |
| Isolate* JSBuiltinReducer::isolate() const { return jsgraph()->isolate(); } |
| |
| |
| CommonOperatorBuilder* JSBuiltinReducer::common() const { |
| return jsgraph()->common(); |
| } |
| |
| |
| MachineOperatorBuilder* JSBuiltinReducer::machine() const { |
| return jsgraph()->machine(); |
| } |
| |
| |
| SimplifiedOperatorBuilder* JSBuiltinReducer::simplified() const { |
| return jsgraph()->simplified(); |
| } |
| |
| } // namespace compiler |
| } // namespace internal |
| } // namespace v8 |