[turbofan] Introduce JSCreateLowering for optimizing JSCreate nodes.

test/unittests/compiler/js-create-lowering-unittest.cc

+// Copyright 2016 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-create-lowering.h"
+#include "src/code-factory.h"
+#include "src/compiler/access-builder.h"
+#include "src/compiler/js-graph.h"
+#include "src/compiler/js-operator.h"
+#include "src/compiler/machine-operator.h"
+#include "src/compiler/node-properties.h"
+#include "src/compiler/operator-properties.h"
+#include "src/isolate-inl.h"
+#include "test/unittests/compiler/compiler-test-utils.h"
+#include "test/unittests/compiler/graph-unittest.h"
+#include "test/unittests/compiler/node-test-utils.h"
+#include "testing/gmock-support.h"
+
+using testing::_;
+using testing::BitEq;
+using testing::IsNaN;
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+class JSCreateLoweringTest : public TypedGraphTest {
+ public:
+  JSCreateLoweringTest()
+      : TypedGraphTest(3), javascript_(zone()), deps_(isolate(), zone()) {}
+  ~JSCreateLoweringTest() override {}
+
+ protected:
+  Reduction Reduce(Node* node) {
+    MachineOperatorBuilder machine(zone());
+    SimplifiedOperatorBuilder simplified(zone());
+    JSGraph jsgraph(isolate(), graph(), common(), javascript(), &simplified,
+                    &machine);
+    // TODO(titzer): mock the GraphReducer here for better unit testing.
+    GraphReducer graph_reducer(zone(), graph());
+    JSCreateLowering reducer(&graph_reducer, &deps_, &jsgraph);
+    return reducer.Reduce(node);
+  }
+
+  Node* FrameState(Handle<SharedFunctionInfo> shared, Node* outer_frame_state) {
+    Node* state_values = graph()->NewNode(common()->StateValues(0));
+    return graph()->NewNode(
+        common()->FrameState(BailoutId::None(),
+                             OutputFrameStateCombine::Ignore(),
+                             common()->CreateFrameStateFunctionInfo(
+                                 FrameStateType::kJavaScriptFunction, 1, 0,
+                                 shared, CALL_MAINTAINS_NATIVE_CONTEXT)),
+        state_values, state_values, state_values, NumberConstant(0),
+        UndefinedConstant(), outer_frame_state);
+  }
+
+  Handle<JSArrayBuffer> NewArrayBuffer(void* bytes, size_t byte_length) {

[Michael Starzinger, 2016/02/08 12:10:40]

nit: This method is not used, let's drop it.

[Benedikt Meurer, 2016/02/08 12:12:05]

Done.

+    Handle<JSArrayBuffer> buffer = factory()->NewJSArrayBuffer();
+    JSArrayBuffer::Setup(buffer, isolate(), true, bytes, byte_length);
+    return buffer;
+  }
+
+  JSOperatorBuilder* javascript() { return &javascript_; }
+
+ private:
+  JSOperatorBuilder javascript_;
+  CompilationDependencies deps_;
+};
+
+TEST_F(JSCreateLoweringTest, JSCreate) {
+  Handle<JSFunction> function = isolate()->object_function();
+  Node* const target = Parameter(Type::Constant(function, graph()->zone()));
+  Node* const context = Parameter(Type::Any());
+  Node* const effect = graph()->start();
+  Reduction r = Reduce(graph()->NewNode(javascript()->Create(), target, target,
+                                        context, EmptyFrameState(), effect));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(
+      r.replacement(),
+      IsFinishRegion(
+          IsAllocate(IsNumberConstant(function->initial_map()->instance_size()),
+                     IsBeginRegion(effect), _),
+          _));
+}
+
+// -----------------------------------------------------------------------------
+// JSCreateArguments
+
+TEST_F(JSCreateLoweringTest, JSCreateArgumentsViaStub) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = UndefinedConstant();
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Node* const frame_state = FrameState(shared, graph()->start());
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->CreateArguments(CreateArgumentsType::kMappedArguments),
+      closure, context, frame_state, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(
+      r.replacement(),
+      IsCall(_,
+             IsHeapConstant(
+                 CodeFactory::ArgumentsAccess(isolate(), false, false).code()),
+             closure, IsNumberConstant(0), _, effect, control));
+}
+
+TEST_F(JSCreateLoweringTest, JSCreateArgumentsRestParameterViaStub) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = UndefinedConstant();
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Node* const frame_state = FrameState(shared, graph()->start());
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->CreateArguments(CreateArgumentsType::kRestParameter),
+      closure, context, frame_state, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(
+      r.replacement(),
+      IsCall(_, IsHeapConstant(
+                    CodeFactory::FastNewRestParameter(isolate()).code()),
+             closure, context, frame_state, effect, control));
+}
+
+TEST_F(JSCreateLoweringTest, JSCreateArgumentsInlinedMapped) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = UndefinedConstant();
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Node* const frame_state_outer = FrameState(shared, graph()->start());
+  Node* const frame_state_inner = FrameState(shared, frame_state_outer);
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->CreateArguments(CreateArgumentsType::kMappedArguments),
+      closure, context, frame_state_inner, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsFinishRegion(
+                  IsAllocate(IsNumberConstant(Heap::kSloppyArgumentsObjectSize),
+                             _, control),
+                  _));
+}
+
+TEST_F(JSCreateLoweringTest, JSCreateArgumentsInlinedUnmapped) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = UndefinedConstant();
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Node* const frame_state_outer = FrameState(shared, graph()->start());
+  Node* const frame_state_inner = FrameState(shared, frame_state_outer);
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->CreateArguments(CreateArgumentsType::kUnmappedArguments),
+      closure, context, frame_state_inner, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsFinishRegion(
+                  IsAllocate(IsNumberConstant(Heap::kStrictArgumentsObjectSize),
+                             _, control),
+                  _));
+}
+
+TEST_F(JSCreateLoweringTest, JSCreateArgumentsInlinedRestArray) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = UndefinedConstant();
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Node* const frame_state_outer = FrameState(shared, graph()->start());
+  Node* const frame_state_inner = FrameState(shared, frame_state_outer);
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->CreateArguments(CreateArgumentsType::kRestParameter),
+      closure, context, frame_state_inner, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsFinishRegion(
+                  IsAllocate(IsNumberConstant(JSArray::kSize), _, control), _));
+}
+
+// -----------------------------------------------------------------------------
+// JSCreateFunctionContext
+
+TEST_F(JSCreateLoweringTest, JSCreateFunctionContextViaInlinedAllocation) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = Parameter(Type::Any());
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Reduction const r =
+      Reduce(graph()->NewNode(javascript()->CreateFunctionContext(8), closure,
+                              context, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsFinishRegion(IsAllocate(IsNumberConstant(Context::SizeFor(
+                                            8 + Context::MIN_CONTEXT_SLOTS)),
+                                        IsBeginRegion(_), control),
+                             _));
+}
+
+// -----------------------------------------------------------------------------
+// JSCreateWithContext
+
+TEST_F(JSCreateLoweringTest, JSCreateWithContext) {
+  Node* const object = Parameter(Type::Receiver());
+  Node* const closure = Parameter(Type::Function());
+  Node* const context = Parameter(Type::Any());
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Reduction r =
+      Reduce(graph()->NewNode(javascript()->CreateWithContext(), object,
+                              closure, context, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsFinishRegion(IsAllocate(IsNumberConstant(Context::SizeFor(
+                                            Context::MIN_CONTEXT_SLOTS)),
+                                        IsBeginRegion(_), control),
+                             _));
+}
+
+// -----------------------------------------------------------------------------
+// JSCreateCatchContext
+
+TEST_F(JSCreateLoweringTest, JSCreateCatchContext) {
+  Handle<String> name = factory()->length_string();
+  Node* const exception = Parameter(Type::Receiver());
+  Node* const closure = Parameter(Type::Function());
+  Node* const context = Parameter(Type::Any());
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Reduction r =
+      Reduce(graph()->NewNode(javascript()->CreateCatchContext(name), exception,
+                              closure, context, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsFinishRegion(IsAllocate(IsNumberConstant(Context::SizeFor(
+                                            Context::MIN_CONTEXT_SLOTS + 1)),
+                                        IsBeginRegion(_), control),
+                             _));
+}
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8