Fix missing cases of empty_string canonicalization

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 1083 matching lines @@
   }
 
   lay(sp, MemOperand(sp, -kNumRequiredStackFrameSlots * kPointerSize));
   StoreP(MemOperand(sp), Operand::Zero(), r0);
   // Set the exit frame sp value to point just before the return address
   // location.
   lay(r1, MemOperand(sp, kStackFrameSPSlot * kPointerSize));
   StoreP(r1, MemOperand(fp, ExitFrameConstants::kSPOffset));
 }
 
-void MacroAssembler::InitializeNewString(Register string, Register length,
-                                         Heap::RootListIndex map_index,
-                                         Register scratch1, Register scratch2) {
-  SmiTag(scratch1, length);
-  LoadRoot(scratch2, map_index);
-  StoreP(scratch1, FieldMemOperand(string, String::kLengthOffset));
-  StoreP(FieldMemOperand(string, String::kHashFieldSlot),
-         Operand(String::kEmptyHashField), scratch1);
-  StoreP(scratch2, FieldMemOperand(string, HeapObject::kMapOffset));
-}
-
 int MacroAssembler::ActivationFrameAlignment() {
 #if !defined(USE_SIMULATOR)
   // Running on the real platform. Use the alignment as mandated by the local
   // environment.
   // Note: This will break if we ever start generating snapshots on one S390
   // platform for another S390 platform with a different alignment.
   return base::OS::ActivationFrameAlignment();
 #else  // Simulated
   // If we are using the simulator then we should always align to the expected
   // alignment. As the simulator is used to generate snapshots we do not know
@@ skipping 4238 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