[cleanup] Delete MacroAssembler::CopyBytes, it is dead code

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 2903 matching lines @@
   // Initialize the JSValue.
   LoadGlobalFunctionInitialMap(constructor, scratch1, scratch2);
   StoreP(scratch1, FieldMemOperand(result, HeapObject::kMapOffset), r0);
   LoadRoot(scratch1, Heap::kEmptyFixedArrayRootIndex);
   StoreP(scratch1, FieldMemOperand(result, JSObject::kPropertiesOffset), r0);
   StoreP(scratch1, FieldMemOperand(result, JSObject::kElementsOffset), r0);
   StoreP(value, FieldMemOperand(result, JSValue::kValueOffset), r0);
   STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
 }
 
-void MacroAssembler::CopyBytes(Register src, Register dst, Register length,
-                               Register scratch) {
-  Label big_loop, left_bytes, done, fake_call;
-
-  DCHECK(!scratch.is(r0));
-
-  // big loop moves 256 bytes at a time
-  bind(&big_loop);
-  CmpP(length, Operand(static_cast<intptr_t>(0x100)));
-  blt(&left_bytes);
-
-  mvc(MemOperand(dst), MemOperand(src), 0x100);
-
-  AddP(src, Operand(static_cast<intptr_t>(0x100)));
-  AddP(dst, Operand(static_cast<intptr_t>(0x100)));
-  SubP(length, Operand(static_cast<intptr_t>(0x100)));
-  b(&big_loop);
-
-  bind(&left_bytes);
-  CmpP(length, Operand::Zero());
-  beq(&done);
-
-  // TODO(john.yan): More optimal version is to use MVC
-  // Sequence below has some undiagnosed issue.
-  /*
-  b(scratch, &fake_call);  // use brasl to Save mvc addr to scratch
-  mvc(MemOperand(dst), MemOperand(src), 1);
-  bind(&fake_call);
-  SubP(length, Operand(static_cast<intptr_t>(-1)));
-  ex(length, MemOperand(scratch));  // execute mvc instr above
-  AddP(src, length);
-  AddP(dst, length);
-  AddP(src, Operand(static_cast<intptr_t>(0x1)));
-  AddP(dst, Operand(static_cast<intptr_t>(0x1)));
-  */
-
-  mvc(MemOperand(dst), MemOperand(src), 1);
-  AddP(src, Operand(static_cast<intptr_t>(0x1)));
-  AddP(dst, Operand(static_cast<intptr_t>(0x1)));
-  SubP(length, Operand(static_cast<intptr_t>(0x1)));
-
-  b(&left_bytes);
-  bind(&done);
-}
-
 void MacroAssembler::InitializeNFieldsWithFiller(Register current_address,
                                                  Register count,
                                                  Register filler) {
   Label loop;
   bind(&loop);
   StoreP(filler, MemOperand(current_address));
   AddP(current_address, current_address, Operand(kPointerSize));
   BranchOnCount(r1, &loop);
 }
 
@@ skipping 2453 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