Use weak cells in map checks in polymorphic ICs.

src/ic/x64/ic-compiler-x64.cc

 // 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/v8.h"
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/ic/ic.h"
 #include "src/ic/ic-compiler.h"
@@ skipping 24 matching lines @@
 
 
 #undef __
 #define __ ACCESS_MASM(masm())
 
 
 Handle<Code> PropertyICCompiler::CompileKeyedStorePolymorphic(
     MapHandleList* receiver_maps, CodeHandleList* handler_stubs,
     MapHandleList* transitioned_maps) {
   Label miss;
-  __ JumpIfSmi(receiver(), &miss, Label::kNear);
+  __ JumpIfSmi(receiver(), &miss);
 
-  __ movp(scratch1(), FieldOperand(receiver(), HeapObject::kMapOffset));
+  Register map_reg = scratch1();
+  __ movp(map_reg, FieldOperand(receiver(), HeapObject::kMapOffset));
   int receiver_count = receiver_maps->length();
   for (int i = 0; i < receiver_count; ++i) {
+    Handle<WeakCell> cell = Map::WeakCellForMap(receiver_maps->at(i));
     // Check map and tail call if there's a match
-    __ Cmp(scratch1(), receiver_maps->at(i));
+    __ CmpWeakValue(map_reg, cell, scratch2());
     if (transitioned_maps->at(i).is_null()) {
       __ j(equal, handler_stubs->at(i), RelocInfo::CODE_TARGET);
     } else {
       Label next_map;
       __ j(not_equal, &next_map, Label::kNear);
-      __ Move(transition_map(), transitioned_maps->at(i),
-              RelocInfo::EMBEDDED_OBJECT);
+      Handle<WeakCell> cell = Map::WeakCellForMap(transitioned_maps->at(i));
+      __ LoadWeakValue(transition_map(), cell, &miss);
       __ jmp(handler_stubs->at(i), RelocInfo::CODE_TARGET);
       __ bind(&next_map);
     }
   }
 
   __ bind(&miss);
 
   TailCallBuiltin(masm(), MissBuiltin(kind()));
 
   // Return the generated code.
@@ skipping 33 matching lines @@
   DCHECK(kind() != Code::KEYED_STORE_IC ||
          map_reg.is(ElementTransitionAndStoreDescriptor::MapRegister()));
   __ movp(map_reg, FieldOperand(receiver(), HeapObject::kMapOffset));
   int receiver_count = types->length();
   int number_of_handled_maps = 0;
   for (int current = 0; current < receiver_count; ++current) {
     Handle<HeapType> type = types->at(current);
     Handle<Map> map = IC::TypeToMap(*type, isolate());
     if (!map->is_deprecated()) {
       number_of_handled_maps++;
+      Handle<WeakCell> cell = Map::WeakCellForMap(map);
       // Check map and tail call if there's a match
-      __ Cmp(map_reg, map);
+      __ CmpWeakValue(map_reg, cell, scratch2());
       if (type->Is(HeapType::Number())) {
         DCHECK(!number_case.is_unused());
         __ bind(&number_case);
       }
       __ j(equal, handlers->at(current), RelocInfo::CODE_TARGET);
     }
   }
   DCHECK(number_of_handled_maps > 0);
 
   __ bind(&miss);
   TailCallBuiltin(masm(), MissBuiltin(kind()));
 
   // Return the generated code.
   InlineCacheState state =
       number_of_handled_maps > 1 ? POLYMORPHIC : MONOMORPHIC;
   return GetCode(kind(), type, name, state);
 }
 
 
 #undef __
 }
 }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64