Reland parts of 'Use weak cells in map checks in polymorphic ICs'

src/x87/macro-assembler-x87.cc

 // Copyright 2012 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_X87
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
@@ skipping 2526 matching lines @@
   AllowDeferredHandleDereference using_raw_address;
   if (isolate()->heap()->InNewSpace(*object)) {
     Handle<Cell> cell = isolate()->factory()->NewCell(object);
     push(Operand::ForCell(cell));
   } else {
     Push(object);
   }
 }
 
 
+void MacroAssembler::CmpWeakValue(Register value, Handle<WeakCell> cell,
+                                  Register scratch) {
+  mov(scratch, cell);
+  cmp(value, FieldOperand(scratch, WeakCell::kValueOffset));
+}
+
+
+void MacroAssembler::LoadWeakValue(Register value, Handle<WeakCell> cell,
+                                   Label* miss) {
+  mov(value, cell);
+  mov(value, FieldOperand(value, WeakCell::kValueOffset));
+  JumpIfSmi(value, miss);
+}
+
+
 void MacroAssembler::Ret() {
   ret(0);
 }
 
 
 void MacroAssembler::Ret(int bytes_dropped, Register scratch) {
   if (is_uint16(bytes_dropped)) {
     ret(bytes_dropped);
   } else {
     pop(scratch);
@@ skipping 805 matching lines @@
   if (mag.shift > 0) sar(edx, mag.shift);
   mov(eax, dividend);
   shr(eax, 31);
   add(edx, eax);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X87