[compiler] Stop delegating CompilationInfo::context.

This implements the CompilationInfo::context explicitly instead of
delegating to the underlying ParseInfo. This is in preparation for
ParseInfo not having to store the context at all soon.

R=jochen@chromium.org

Review-Url: https://codereview.chromium.org/2316083002
Cr-Commit-Position: refs/heads/master@{#39244}

src/compilation-info.cc

@@ -27,8 +27,6 @@ namespace internal {
 PARSE_INFO_GETTER(Handle<Script>, script)
 PARSE_INFO_GETTER(FunctionLiteral*, literal)
 PARSE_INFO_GETTER_WITH_DEFAULT(DeclarationScope*, scope, nullptr)
-PARSE_INFO_GETTER_WITH_DEFAULT(Handle<Context>, context,
-                               Handle<Context>::null())
 PARSE_INFO_GETTER(Handle<SharedFunctionInfo>, shared_info)
 
 #undef PARSE_INFO_GETTER
@@ -178,6 +176,12 @@ bool CompilationInfo::ExpectsJSReceiverAsReceiver() {
   return is_sloppy(parse_info()->language_mode()) && !parse_info()->is_native();
 }
 
+bool CompilationInfo::has_context() const { return !closure().is_null(); }
+
+Context* CompilationInfo::context() const {
+  return has_context() ? closure()->context() : nullptr;
+}
+
 bool CompilationInfo::has_native_context() const {
   return !closure().is_null() && (closure()->native_context() != nullptr);
 }

src/compilation-info.h

@@ -68,7 +68,6 @@ class CompilationInfo final {
   Handle<Script> script() const;
   FunctionLiteral* literal() const;
   DeclarationScope* scope() const;
-  Handle<Context> context() const;
   Handle<SharedFunctionInfo> shared_info() const;
   bool has_shared_info() const;
   // -----------------------------------------------------------
@@ -218,6 +217,9 @@ class CompilationInfo final {
            (FLAG_trap_on_stub_deopt && IsStub());
   }
 
+  bool has_context() const;
+  Context* context() const;
+
   bool has_native_context() const;
   Context* native_context() const;
 

src/compiler/code-generator.cc

@@ -284,7 +284,7 @@ void CodeGenerator::RecordSafepoint(ReferenceMap* references,
 bool CodeGenerator::IsMaterializableFromFrame(Handle<HeapObject> object,
                                               int* slot_return) {
   if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) {
-    if (object.is_identical_to(info()->context()) && !info()->is_osr()) {
+    if (*object == info()->context() && !info()->is_osr()) {
       *slot_return = Frame::kContextSlot;
       return true;
     } else if (object.is_identical_to(info()->closure())) {

src/compiler/pipeline.cc

@@ -799,7 +799,7 @@ struct InliningPhase {
     JSContextSpecialization context_specialization(
         &graph_reducer, data->jsgraph(),
         data->info()->is_function_context_specializing()
-            ? data->info()->context()
+            ? handle(data->info()->context())
             : MaybeHandle<Context>());
     JSFrameSpecialization frame_specialization(data->info()->osr_frame(),
                                                data->jsgraph());