Remove high promotion mode.

src/x64/macro-assembler-x64.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 "v8.h"
 
 #if V8_TARGET_ARCH_X64
 
 #include "bootstrapper.h"
 #include "codegen.h"
@@ skipping 4542 matching lines @@
   // Set the map. The other fields are left uninitialized.
   LoadRoot(kScratchRegister, Heap::kConsStringMapRootIndex);
   movp(FieldOperand(result, HeapObject::kMapOffset), kScratchRegister);
 }
 
 
 void MacroAssembler::AllocateAsciiConsString(Register result,
                                              Register scratch1,
                                              Register scratch2,
                                              Label* gc_required) {
-  Label allocate_new_space, install_map;
-  AllocationFlags flags = TAG_OBJECT;
-
-  ExternalReference high_promotion_mode = ExternalReference::
-      new_space_high_promotion_mode_active_address(isolate());
-
-  Load(scratch1, high_promotion_mode);
-  testb(scratch1, Immediate(1));
-  j(zero, &allocate_new_space);
   Allocate(ConsString::kSize,
            result,
            scratch1,
            scratch2,
            gc_required,
-           static_cast<AllocationFlags>(flags | PRETENURE_OLD_POINTER_SPACE));
-
-  jmp(&install_map);
-
-  bind(&allocate_new_space);
-  Allocate(ConsString::kSize,
-           result,
-           scratch1,
-           scratch2,
-           gc_required,
-           flags);
-
-  bind(&install_map);
+           TAG_OBJECT);
 
   // Set the map. The other fields are left uninitialized.
   LoadRoot(kScratchRegister, Heap::kConsAsciiStringMapRootIndex);
   movp(FieldOperand(result, HeapObject::kMapOffset), kScratchRegister);
 }
 
 
 void MacroAssembler::AllocateTwoByteSlicedString(Register result,
                                           Register scratch1,
                                           Register scratch2,
@@ skipping 634 matching lines @@
   if (ms.shift() > 0) sarl(rdx, Immediate(ms.shift()));
   movl(rax, dividend);
   shrl(rax, Immediate(31));
   addl(rdx, rax);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64