Revert of [intrinsic] Drop the %_ValueOf intrinsic.

src/full-codegen/mips/full-codegen-mips.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.
 
 #if V8_TARGET_ARCH_MIPS
 
 // Note on Mips implementation:
 //
 // The result_register() for mips is the 'v0' register, which is defined
 // by the ABI to contain function return values. However, the first
@@ skipping 2841 matching lines @@
   // Non-JS objects have class null.
   __ bind(&null);
   __ LoadRoot(v0, Heap::kNullValueRootIndex);
 
   // All done.
   __ bind(&done);
 
   context()->Plug(v0);
 }
 
+
+void FullCodeGenerator::EmitValueOf(CallRuntime* expr) {
+  ZoneList<Expression*>* args = expr->arguments();
+  DCHECK(args->length() == 1);
+
+  VisitForAccumulatorValue(args->at(0));  // Load the object.
+
+  Label done;
+  // If the object is a smi return the object.
+  __ JumpIfSmi(v0, &done);
+  // If the object is not a value type, return the object.
+  __ GetObjectType(v0, a1, a1);
+  __ Branch(&done, ne, a1, Operand(JS_VALUE_TYPE));
+
+  __ lw(v0, FieldMemOperand(v0, JSValue::kValueOffset));
+
+  __ bind(&done);
+  context()->Plug(v0);
+}
+
 
 void FullCodeGenerator::EmitStringCharFromCode(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label done;
   StringCharFromCodeGenerator generator(v0, a1);
   generator.GenerateFast(masm_);
@@ skipping 908 matching lines @@
          reinterpret_cast<uint32_t>(
              isolate->builtins()->OnStackReplacement()->entry()));
   return ON_STACK_REPLACEMENT;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS