[crankshaft] Fragmentation-free allocation folding.

src/crankshaft/arm64/lithium-arm64.cc

 // Copyright 2013 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 "src/crankshaft/arm64/lithium-arm64.h"
 
 #include <sstream>
 
 #include "src/crankshaft/arm64/lithium-codegen-arm64.h"
 #include "src/crankshaft/hydrogen-osr.h"
@@ skipping 823 matching lines @@
   } else if (instr->representation().IsDouble()) {
     return DoArithmeticD(Token::ADD, instr);
   } else {
     DCHECK(instr->representation().IsTagged());
     return DoArithmeticT(Token::ADD, instr);
   }
 }
 
 
 LInstruction* LChunkBuilder::DoAllocate(HAllocate* instr) {
-  info()->MarkAsDeferredCalling();
-  LOperand* context = UseAny(instr->context());
   LOperand* size = UseRegisterOrConstant(instr->size());
   LOperand* temp1 = TempRegister();
   LOperand* temp2 = TempRegister();
-  LOperand* temp3 = instr->MustPrefillWithFiller() ? TempRegister() : NULL;
-  LAllocate* result = new(zone()) LAllocate(context, size, temp1, temp2, temp3);
-  return AssignPointerMap(DefineAsRegister(result));
+  if (instr->IsAllocationFolded()) {
+    LFastAllocate* result = new (zone()) LFastAllocate(size, temp1, temp2);
+    return DefineAsRegister(result);
+  } else {
+    info()->MarkAsDeferredCalling();
+    LOperand* context = UseAny(instr->context());
+    LOperand* temp3 = instr->MustPrefillWithFiller() ? TempRegister() : NULL;
+    LAllocate* result =
+        new (zone()) LAllocate(context, size, temp1, temp2, temp3);
+    return AssignPointerMap(DefineAsRegister(result));
+  }
 }
 
 
 LInstruction* LChunkBuilder::DoApplyArguments(HApplyArguments* instr) {
   LOperand* function = UseFixed(instr->function(), x1);
   LOperand* receiver = UseFixed(instr->receiver(), x0);
   LOperand* length = UseFixed(instr->length(), x2);
   LOperand* elements = UseFixed(instr->elements(), x3);
   LApplyArguments* result = new(zone()) LApplyArguments(function,
                                                         receiver,
@@ skipping 1753 matching lines @@
 
 LInstruction* LChunkBuilder::DoWrapReceiver(HWrapReceiver* instr) {
   LOperand* receiver = UseRegister(instr->receiver());
   LOperand* function = UseRegister(instr->function());
   LWrapReceiver* result = new(zone()) LWrapReceiver(receiver, function);
   return AssignEnvironment(DefineAsRegister(result));
 }
 
 }  // namespace internal
 }  // namespace v8