[runtime] Remove the redundant %_IsObject intrinsic.

src/full-codegen/arm64/full-codegen-arm64.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.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/compiler.h"
@@ skipping 3047 matching lines @@
 
   uint64_t sign_mask = V8_UINT64_C(1) << (kSmiShift + kSmiValueSize - 1);
 
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   __ TestAndSplit(x0, kSmiTagMask | sign_mask, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
-void FullCodeGenerator::EmitIsObject(CallRuntime* expr) {
-  ZoneList<Expression*>* args = expr->arguments();
-  DCHECK(args->length() == 1);
-
-  VisitForAccumulatorValue(args->at(0));
-
-  Label materialize_true, materialize_false;
-  Label* if_true = NULL;
-  Label* if_false = NULL;
-  Label* fall_through = NULL;
-  context()->PrepareTest(&materialize_true, &materialize_false,
-                         &if_true, &if_false, &fall_through);
-
-  __ JumpIfSmi(x0, if_false);
-  __ JumpIfRoot(x0, Heap::kNullValueRootIndex, if_true);
-  __ Ldr(x10, FieldMemOperand(x0, HeapObject::kMapOffset));
-  // Undetectable objects behave like undefined when tested with typeof.
-  __ Ldrb(x11, FieldMemOperand(x10, Map::kBitFieldOffset));
-  __ Tbnz(x11, Map::kIsUndetectable, if_false);
-  __ Ldrb(x12, FieldMemOperand(x10, Map::kInstanceTypeOffset));
-  __ Cmp(x12, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE);
-  __ B(lt, if_false);
-  __ Cmp(x12, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
-  PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  Split(le, if_true, if_false, fall_through);
-
-  context()->Plug(if_true, if_false);
-}
-
-
 void FullCodeGenerator::EmitIsSpecObject(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
@@ skipping 2293 matching lines @@
   }
 
   return INTERRUPT;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64