Move function prototype handling into a special handler rather than IC

src/arm/lithium-codegen-arm.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"
 
 #include "src/arm/lithium-codegen-arm.h"
 #include "src/arm/lithium-gap-resolver-arm.h"
 #include "src/code-stubs.h"
 #include "src/hydrogen-osr.h"
@@ skipping 3125 matching lines @@
   Handle<Code> ic = LoadIC::initialize_stub(isolate(), NOT_CONTEXTUAL);
   CallCode(ic, RelocInfo::CODE_TARGET, instr, NEVER_INLINE_TARGET_ADDRESS);
 }
 
 
 void LCodeGen::DoLoadFunctionPrototype(LLoadFunctionPrototype* instr) {
   Register scratch = scratch0();
   Register function = ToRegister(instr->function());
   Register result = ToRegister(instr->result());
 
-  // Check that the function really is a function. Load map into the
-  // result register.
-  __ CompareObjectType(function, result, scratch, JS_FUNCTION_TYPE);
-  DeoptimizeIf(ne, instr->environment());
-
-  // Make sure that the function has an instance prototype.
-  Label non_instance;
-  __ ldrb(scratch, FieldMemOperand(result, Map::kBitFieldOffset));
-  __ tst(scratch, Operand(1 << Map::kHasNonInstancePrototype));
-  __ b(ne, &non_instance);
-
   // Get the prototype or initial map from the function.
   __ ldr(result,
          FieldMemOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
 
   // Check that the function has a prototype or an initial map.
   __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
   __ cmp(result, ip);
   DeoptimizeIf(eq, instr->environment());
 
   // If the function does not have an initial map, we're done.
   Label done;
   __ CompareObjectType(result, scratch, scratch, MAP_TYPE);
   __ b(ne, &done);
 
   // Get the prototype from the initial map.
   __ ldr(result, FieldMemOperand(result, Map::kPrototypeOffset));
-  __ jmp(&done);
-
-  // Non-instance prototype: Fetch prototype from constructor field
-  // in initial map.
-  __ bind(&non_instance);
-  __ ldr(result, FieldMemOperand(result, Map::kConstructorOffset));
 
   // All done.
   __ bind(&done);
 }
 
 
 void LCodeGen::DoLoadRoot(LLoadRoot* instr) {
   Register result = ToRegister(instr->result());
   __ LoadRoot(result, instr->index());
 }
@@ skipping 2701 matching lines @@
   __ Push(scope_info);
   __ push(ToRegister(instr->function()));
   CallRuntime(Runtime::kPushBlockContext, 2, instr);
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal