[runtime] Replace global object link with native context link in all contexts.

src/crankshaft/hydrogen.cc

 // Copyright 2013 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/crankshaft/hydrogen.h"
 
 #include <sstream>
 
 #include "src/allocation-site-scopes.h"
 #include "src/ast/ast-numbering.h"
@@ skipping 1841 matching lines @@
   // the JSRegExpResult allocation.
   ElementsKind elements_kind = FAST_ELEMENTS;
   HValue* size = BuildCalculateElementsSize(elements_kind, length);
 
   // Allocate the JSRegExpResult and the FixedArray in one step.
   HValue* result = Add<HAllocate>(
       Add<HConstant>(JSRegExpResult::kSize), HType::JSArray(),
       NOT_TENURED, JS_ARRAY_TYPE);
 
   // Initialize the JSRegExpResult header.
-  HValue* global_object = Add<HLoadNamedField>(
+  HValue* native_context = Add<HLoadNamedField>(
       context(), nullptr,
-      HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
-  HValue* native_context = Add<HLoadNamedField>(
-      global_object, nullptr, HObjectAccess::ForJSGlobalObjectNativeContext());
+      HObjectAccess::ForContextSlot(Context::NATIVE_CONTEXT_INDEX));
   Add<HStoreNamedField>(
       result, HObjectAccess::ForMap(),
       Add<HLoadNamedField>(
           native_context, nullptr,
           HObjectAccess::ForContextSlot(Context::REGEXP_RESULT_MAP_INDEX)));
   HConstant* empty_fixed_array =
       Add<HConstant>(isolate()->factory()->empty_fixed_array());
   Add<HStoreNamedField>(
       result, HObjectAccess::ForJSArrayOffset(JSArray::kPropertiesOffset),
       empty_fixed_array);
@@ skipping 1376 matching lines @@
     // since the counter is bounded by the new space size.
     memento_create_count->ClearFlag(HValue::kCanOverflow);
     Add<HStoreNamedField>(
         allocation_site, HObjectAccess::ForAllocationSiteOffset(
             AllocationSite::kPretenureCreateCountOffset), memento_create_count);
   }
 }
 
 
 HInstruction* HGraphBuilder::BuildGetNativeContext() {
-  // Get the global object, then the native context
-  HValue* global_object = Add<HLoadNamedField>(
+  return Add<HLoadNamedField>(
       context(), nullptr,
-      HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
-  return Add<HLoadNamedField>(global_object, nullptr,
-                              HObjectAccess::ForObservableJSObjectOffset(
-                                  JSGlobalObject::kNativeContextOffset));
+      HObjectAccess::ForContextSlot(Context::NATIVE_CONTEXT_INDEX));
 }
 
 
 HInstruction* HGraphBuilder::BuildGetNativeContext(HValue* closure) {
   // Get the global object, then the native context
   HInstruction* context = Add<HLoadNamedField>(
       closure, nullptr, HObjectAccess::ForFunctionContextPointer());
-  HInstruction* global_object = Add<HLoadNamedField>(
+  return Add<HLoadNamedField>(
       context, nullptr,
-      HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
-  HObjectAccess access = HObjectAccess::ForObservableJSObjectOffset(
-      JSGlobalObject::kNativeContextOffset);
-  return Add<HLoadNamedField>(global_object, nullptr, access);
+      HObjectAccess::ForContextSlot(Context::NATIVE_CONTEXT_INDEX));
 }
 
 
 HInstruction* HGraphBuilder::BuildGetScriptContext(int context_index) {
   HValue* native_context = BuildGetNativeContext();
   HValue* script_context_table = Add<HLoadNamedField>(
       native_context, nullptr,
       HObjectAccess::ForContextSlot(Context::SCRIPT_CONTEXT_TABLE_INDEX));
   return Add<HLoadNamedField>(script_context_table, nullptr,
                               HObjectAccess::ForScriptContext(context_index));
@@ skipping 250 matching lines @@
   if (fill_mode == FILL_WITH_HOLE) {
     builder()->BuildFillElementsWithHole(elements_location_, kind_,
                                          graph()->GetConstant0(), capacity);
   }
 
   return array_object;
 }
 
 
 HValue* HGraphBuilder::AddLoadJSBuiltin(int context_index) {
-  HValue* global_object = Add<HLoadNamedField>(
-      context(), nullptr,
-      HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
-  HObjectAccess access = HObjectAccess::ForObservableJSObjectOffset(
-      JSGlobalObject::kNativeContextOffset);
-  HValue* native_context = Add<HLoadNamedField>(global_object, nullptr, access);
+  HValue* native_context = BuildGetNativeContext();
   HObjectAccess function_access = HObjectAccess::ForContextSlot(context_index);
   return Add<HLoadNamedField>(native_context, nullptr, function_access);
 }
 
 
 HOptimizedGraphBuilder::HOptimizedGraphBuilder(CompilationInfo* info)
     : HGraphBuilder(info),
       function_state_(NULL),
       initial_function_state_(this, info, NORMAL_RETURN, 0),
       ast_context_(NULL),
@@ skipping 2138 matching lines @@
           } else {
             instr = New<HLoadNamedField>(cell_constant, nullptr, access,
                                          field_maps, HType::HeapObject());
           }
           instr->ClearDependsOnFlag(kInobjectFields);
           instr->SetDependsOnFlag(kGlobalVars);
           return ast_context()->ReturnInstruction(instr, expr->id());
         }
       } else {
         HValue* global_object = Add<HLoadNamedField>(
-            context(), nullptr,
-            HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
+            BuildGetNativeContext(), nullptr,
+            HObjectAccess::ForContextSlot(Context::EXTENSION_INDEX));
         HLoadGlobalGeneric* instr = New<HLoadGlobalGeneric>(
             global_object, variable->name(), ast_context()->typeof_mode());
         instr->SetVectorAndSlot(handle(current_feedback_vector(), isolate()),
                                 expr->VariableFeedbackSlot());
         return ast_context()->ReturnInstruction(instr, expr->id());
       }
     }
 
     case VariableLocation::PARAMETER:
     case VariableLocation::LOCAL: {
@@ skipping 1192 matching lines @@
       }
     }
     HInstruction* instr = Add<HStoreNamedField>(cell_constant, access, value);
     instr->ClearChangesFlag(kInobjectFields);
     instr->SetChangesFlag(kGlobalVars);
     if (instr->HasObservableSideEffects()) {
       Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
     }
   } else {
     HValue* global_object = Add<HLoadNamedField>(
-        context(), nullptr,
-        HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
+        BuildGetNativeContext(), nullptr,
+        HObjectAccess::ForContextSlot(Context::EXTENSION_INDEX));
     HStoreNamedGeneric* instr =
         Add<HStoreNamedGeneric>(global_object, var->name(), value,
                                 function_language_mode(), PREMONOMORPHIC);
     Handle<TypeFeedbackVector> vector =
         handle(current_feedback_vector(), isolate());
     instr->SetVectorAndSlot(vector, slot);
     USE(instr);
     DCHECK(instr->HasObservableSideEffects());
     Add<HSimulate>(ast_id, REMOVABLE_SIMULATE);
   }
@@ skipping 3081 matching lines @@
   // We HForceRepresentation here to avoid allocations during an *-to-tagged
   // HChange that could cause GC while the array buffer object is not fully
   // initialized.
   HObjectAccess byte_length_access(HObjectAccess::ForJSArrayBufferByteLength());
   byte_length = AddUncasted<HForceRepresentation>(
       byte_length, byte_length_access.representation());
   HAllocate* result =
       BuildAllocate(Add<HConstant>(JSArrayBuffer::kSizeWithInternalFields),
                     HType::JSObject(), JS_ARRAY_BUFFER_TYPE, HAllocationMode());
 
-  HValue* global_object = Add<HLoadNamedField>(
-      context(), nullptr,
-      HObjectAccess::ForContextSlot(Context::GLOBAL_OBJECT_INDEX));
-  HValue* native_context = Add<HLoadNamedField>(
-      global_object, nullptr, HObjectAccess::ForJSGlobalObjectNativeContext());
+  HValue* native_context = BuildGetNativeContext();
   Add<HStoreNamedField>(
       result, HObjectAccess::ForMap(),
       Add<HLoadNamedField>(
           native_context, nullptr,
           HObjectAccess::ForContextSlot(Context::ARRAY_BUFFER_MAP_INDEX)));
 
   HConstant* empty_fixed_array =
       Add<HConstant>(isolate()->factory()->empty_fixed_array());
   Add<HStoreNamedField>(
       result, HObjectAccess::ForJSArrayOffset(JSArray::kPropertiesOffset),
@@ skipping 3588 matching lines @@
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8