[stubs] Port LoadFunctionPrototypeStub to CSA

src/mips64/macro-assembler-mips64.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 <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
@@ skipping 4919 matching lines @@
   ld(result, FieldMemOperand(map, Map::kConstructorOrBackPointerOffset));
   bind(&loop);
   JumpIfSmi(result, &done);
   GetObjectType(result, temp, temp2);
   Branch(&done, ne, temp2, Operand(MAP_TYPE));
   ld(result, FieldMemOperand(result, Map::kConstructorOrBackPointerOffset));
   Branch(&loop);
   bind(&done);
 }
 
-
-void MacroAssembler::TryGetFunctionPrototype(Register function, Register result,
-                                             Register scratch, Label* miss) {
-  // Get the prototype or initial map from the function.
-  ld(result,
-     FieldMemOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
-
-  // If the prototype or initial map is the hole, don't return it and
-  // simply miss the cache instead. This will allow us to allocate a
-  // prototype object on-demand in the runtime system.
-  LoadRoot(t8, Heap::kTheHoleValueRootIndex);
-  Branch(miss, eq, result, Operand(t8));
-
-  // If the function does not have an initial map, we're done.
-  Label done;
-  GetObjectType(result, scratch, scratch);
-  Branch(&done, ne, scratch, Operand(MAP_TYPE));
-
-  // Get the prototype from the initial map.
-  ld(result, FieldMemOperand(result, Map::kPrototypeOffset));
-
-  // All done.
-  bind(&done);
-}
-
-
 void MacroAssembler::GetObjectType(Register object,
                                    Register map,
                                    Register type_reg) {
   ld(map, FieldMemOperand(object, HeapObject::kMapOffset));
   lbu(type_reg, FieldMemOperand(map, Map::kInstanceTypeOffset));
 }
 
 
 // -----------------------------------------------------------------------------
 // Runtime calls.
@@ skipping 1949 matching lines @@
   if (mag.shift > 0) sra(result, result, mag.shift);
   srl(at, dividend, 31);
   Addu(result, result, Operand(at));
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64