[stubs] Port LoadFunctionPrototypeStub to CSA

src/s390/macro-assembler-s390.cc

 // Copyright 2014 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 <assert.h>  // For assert
 #include <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #if V8_TARGET_ARCH_S390
 
 #include "src/base/bits.h"
@@ skipping 1948 matching lines @@
   LoadP(result, FieldMemOperand(map, Map::kConstructorOrBackPointerOffset));
   bind(&loop);
   JumpIfSmi(result, &done);
   CompareObjectType(result, temp, temp2, MAP_TYPE);
   bne(&done);
   LoadP(result, FieldMemOperand(result, Map::kConstructorOrBackPointerOffset));
   b(&loop);
   bind(&done);
 }
 
-void MacroAssembler::TryGetFunctionPrototype(Register function, Register result,
-                                             Register scratch, Label* miss) {
-  // Get the prototype or initial map from the function.
-  LoadP(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.
-  CompareRoot(result, Heap::kTheHoleValueRootIndex);
-  beq(miss);
-
-  // If the function does not have an initial map, we're done.
-  Label done;
-  CompareObjectType(result, scratch, scratch, MAP_TYPE);
-  bne(&done, Label::kNear);
-
-  // Get the prototype from the initial map.
-  LoadP(result, FieldMemOperand(result, Map::kPrototypeOffset));
-
-  // All done.
-  bind(&done);
-}
-
 void MacroAssembler::CallStub(CodeStub* stub, TypeFeedbackId ast_id,
                               Condition cond) {
   DCHECK(AllowThisStubCall(stub));  // Stub calls are not allowed in some stubs.
   Call(stub->GetCode(), RelocInfo::CODE_TARGET, ast_id, cond);
 }
 
 void MacroAssembler::TailCallStub(CodeStub* stub, Condition cond) {
   Jump(stub->GetCode(), RelocInfo::CODE_TARGET, cond);
 }
 
@@ skipping 3349 matching lines @@
   }
   if (mag.shift > 0) ShiftRightArith(result, result, Operand(mag.shift));
   ExtractBit(r0, dividend, 31);
   AddP(result, r0);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_S390