[Interpreter] Adds implementation of bytecode graph builder for LoadICSloppy/Strict

src/compiler/bytecode-graph-builder.cc

 // 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/compiler/bytecode-graph-builder.h"
 
 #include "src/compiler/linkage.h"
 #include "src/compiler/operator-properties.h"
 #include "src/interpreter/bytecode-array-iterator.h"
 
@@ skipping 80 matching lines @@
 bool BytecodeGraphBuilder::Environment::IsMarkedAsUnreachable() const {
   return GetControlDependency()->opcode() == IrOpcode::kDead;
 }
 
 
 void BytecodeGraphBuilder::Environment::MarkAsUnreachable() {
   UpdateControlDependency(builder()->jsgraph()->Dead());
 }
 
 
+class BytecodeGraphBuilder::FrameStateBeforeAndAfter {
+ public:
+  explicit FrameStateBeforeAndAfter(BytecodeGraphBuilder* builder)
+      : builder_(builder) {
+    // TODO(mythria): Replace with the actual frame state. Current
+    // implementation introduces empty frame state.
+    frame_state_before_ = builder_->jsgraph()->EmptyFrameState();
+  }
+
+  void AddToNode(Node* node) {
+    int count = OperatorProperties::GetFrameStateInputCount(node->op());
+    DCHECK_LE(count, 2);
+    if (count >= 1) {
+      // Add the frame state for after the operation.
+      DCHECK_EQ(IrOpcode::kDead,
+                NodeProperties::GetFrameStateInput(node, 0)->opcode());
+
+      // TODO(mythria): Replace with the actual frame state. Current
+      // implementation introduces empty frame state.
+      NodeProperties::ReplaceFrameStateInput(
+          node, 0, builder_->jsgraph()->EmptyFrameState());
+    }
+    if (count >= 2) {
+      // Add the frame state for before the operation.
+      DCHECK_EQ(IrOpcode::kDead,
+                NodeProperties::GetFrameStateInput(node, 1)->opcode());
+      NodeProperties::ReplaceFrameStateInput(node, 1, frame_state_before_);
+    }
+  }
+
+ private:
+  BytecodeGraphBuilder* builder_;
+  Node* frame_state_before_;
+};
+
+
 BytecodeGraphBuilder::BytecodeGraphBuilder(Zone* local_zone,
                                            CompilationInfo* compilation_info,
                                            JSGraph* jsgraph)
     : local_zone_(local_zone),
       info_(compilation_info),
       jsgraph_(jsgraph),
       input_buffer_size_(0),
       input_buffer_(nullptr),
       exit_controls_(local_zone) {
   bytecode_array_ = handle(info()->shared_info()->bytecode_array());
 }
 
 
 Node* BytecodeGraphBuilder::GetFunctionContext() {
   if (!function_context_.is_set()) {
     // Parameter (arity + 1) is special for the outer context of the function
     const Operator* op =
         common()->Parameter(bytecode_array()->parameter_count(), "%context");
     Node* node = NewNode(op, graph()->start());
     function_context_.set(node);
   }
   return function_context_.get();
 }
 
 
+Node* BytecodeGraphBuilder::GetFunctionClosure() {
+  if (!function_closure_.is_set()) {
+    const Operator* op = common()->Parameter(
+        Linkage::kJSFunctionCallClosureParamIndex, "%closure");
+    Node* node = NewNode(op, graph()->start());
+    function_closure_.set(node);
+  }
+  return function_closure_.get();
+}
+
+
+Node* BytecodeGraphBuilder::BuildLoadImmutableObjectField(Node* object,
+                                                          int offset) {
+  return graph()->NewNode(jsgraph()->machine()->Load(kMachAnyTagged), object,
+                          jsgraph()->IntPtrConstant(offset - kHeapObjectTag),
+                          graph()->start(), graph()->start());
+}
+
+
+Node* BytecodeGraphBuilder::BuildLoadFeedbackVector() {
+  if (!feedback_vector_.is_set()) {
+    Node* closure = GetFunctionClosure();
+    Node* shared = BuildLoadImmutableObjectField(
+        closure, JSFunction::kSharedFunctionInfoOffset);
+    Node* vector = BuildLoadImmutableObjectField(
+        shared, SharedFunctionInfo::kFeedbackVectorOffset);
+    feedback_vector_.set(vector);
+  }
+  return feedback_vector_.get();
+}
+
+
+VectorSlotPair BytecodeGraphBuilder::CreateVectorSlotPair(int slot_id) {
+  FeedbackVectorSlot slot = info()->feedback_vector()->ToSlot(slot_id);
+  return CreateVectorSlotPair(slot);
+}
+
+
+VectorSlotPair BytecodeGraphBuilder::CreateVectorSlotPair(

[rmcilroy, 2015/11/09 15:23:00]

Just inline this into the function above (I don't see a situation where we would
get a FeedbackVectorSlot without having first had to call ToSlot on an int).
Also, when you do this pull out feedback_vector as a variable so that you get it
once, rather than getting it from info and info->shared each time.

[mythria, 2015/11/10 09:55:35]

Done.

+    FeedbackVectorSlot slot) {
+  return VectorSlotPair(handle(info()->shared_info()->feedback_vector()), slot);
+}
+
+
+// TODO(mythria): This implementation introduces empty frame state. Replace with

[rmcilroy, 2015/11/09 15:23:00]

nit - /empty frame state/an empty frame state/

[mythria, 2015/11/10 09:55:35]

Done.

+// the correct frame state.
+void BytecodeGraphBuilder::PrepareFrameState(Node* node) {

[rmcilroy, 2015/11/09 15:23:00]

Unused? If so, please remove for now.

[mythria, 2015/11/10 09:55:35]

Done.

+  int count = OperatorProperties::GetFrameStateInputCount(node->op());
+  if (count > 0) {
+    DCHECK_EQ(1, count);
+    DCHECK_EQ(IrOpcode::kDead,
+              NodeProperties::GetFrameStateInput(node, 0)->opcode());
+    NodeProperties::ReplaceFrameStateInput(node, 0,
+                                           jsgraph()->EmptyFrameState());
+  }
+}
+
+
 bool BytecodeGraphBuilder::CreateGraph(bool stack_check) {
   // Set up the basic structure of the graph. Outputs for {Start} are
   // the formal parameters (including the receiver) plus context and
   // closure.
 
   // The additional count items are for the context and closure.
   int actual_parameter_count = bytecode_array()->parameter_count() + 2;
   graph()->SetStart(graph()->NewNode(common()->Start(actual_parameter_count)));
 
   Environment env(this, bytecode_array()->register_count(),
@@ skipping 172 matching lines @@
   UNIMPLEMENTED();
 }
 
 
 void BytecodeGraphBuilder::VisitStaContextSlot(
     const interpreter::BytecodeArrayIterator& iterator) {
   UNIMPLEMENTED();
 }
 
 
+void BytecodeGraphBuilder::BuildNamedLoad(
+    const interpreter::BytecodeArrayIterator& iterator) {
+  FrameStateBeforeAndAfter states(this);
+  Node* object = environment()->LookupRegister(iterator.GetRegisterOperand(0));
+  Handle<Name> name =
+      Handle<Name>::cast(iterator.GetConstantForIndexOperand(1));
+  VectorSlotPair feedback = CreateVectorSlotPair(iterator.GetIndexOperand(2));
+
+  const Operator* op = javascript()->LoadNamed(language_mode(), name, feedback);
+  Node* node = NewNode(op, object, BuildLoadFeedbackVector());
+  states.AddToNode(node);
+  environment()->BindAccumulator(node);
+}
+
+
 void BytecodeGraphBuilder::VisitLoadICSloppy(
     const interpreter::BytecodeArrayIterator& iterator) {
-  UNIMPLEMENTED();
+  DCHECK(is_sloppy(language_mode()));
+  BuildNamedLoad(iterator);
 }
 
 
 void BytecodeGraphBuilder::VisitLoadICStrict(
     const interpreter::BytecodeArrayIterator& iterator) {
-  UNIMPLEMENTED();
+  DCHECK(is_strict(language_mode()));
+  BuildNamedLoad(iterator);
 }
 
 
 void BytecodeGraphBuilder::VisitKeyedLoadICSloppy(
     const interpreter::BytecodeArrayIterator& iterator) {
   UNIMPLEMENTED();
 }
 
 
 void BytecodeGraphBuilder::VisitKeyedLoadICStrict(
     const interpreter::BytecodeArrayIterator& iterator) {
   UNIMPLEMENTED();
 }
 
 
 void BytecodeGraphBuilder::VisitLoadICSloppyWide(
     const interpreter::BytecodeArrayIterator& iterator) {
-  UNIMPLEMENTED();
+  DCHECK(is_sloppy(language_mode()));
+  BuildNamedLoad(iterator);
 }
 
 
 void BytecodeGraphBuilder::VisitLoadICStrictWide(
     const interpreter::BytecodeArrayIterator& iterator) {
-  UNIMPLEMENTED();
+  DCHECK(is_strict(language_mode()));
+  BuildNamedLoad(iterator);
 }
 
 
 void BytecodeGraphBuilder::VisitKeyedLoadICSloppyWide(
     const interpreter::BytecodeArrayIterator& iterator) {
   UNIMPLEMENTED();
 }
 
 
 void BytecodeGraphBuilder::VisitKeyedLoadICStrictWide(
@@ skipping 531 matching lines @@
 
 void BytecodeGraphBuilder::UpdateControlDependencyToLeaveFunction(Node* exit) {
   if (environment()->IsMarkedAsUnreachable()) return;
   environment()->MarkAsUnreachable();
   exit_controls_.push_back(exit);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8