Version 2.3.6

src/ia32/macro-assembler-ia32.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 654 matching lines @@
                                         Register result,
                                         Register result_end,
                                         Register scratch,
                                         Label* gc_required,
                                         AllocationFlags flags) {
   ASSERT(!result.is(result_end));
 
   // Load address of new object into result.
   LoadAllocationTopHelper(result, result_end, scratch, flags);
 
+  Register top_reg = result_end.is_valid() ? result_end : result;
+
   // Calculate new top and bail out if new space is exhausted.
   ExternalReference new_space_allocation_limit =
       ExternalReference::new_space_allocation_limit_address();
-  lea(result_end, Operand(result, object_size));
-  cmp(result_end, Operand::StaticVariable(new_space_allocation_limit));
+
+  if (top_reg.is(result)) {
+    add(Operand(top_reg), Immediate(object_size));
+  } else {
+    lea(top_reg, Operand(result, object_size));
+  }
+  cmp(top_reg, Operand::StaticVariable(new_space_allocation_limit));
   j(above, gc_required, not_taken);
 
+  // Update allocation top.
+  UpdateAllocationTopHelper(top_reg, scratch);
+
   // Tag result if requested.
-  if ((flags & TAG_OBJECT) != 0) {
-    lea(result, Operand(result, kHeapObjectTag));
+  if (top_reg.is(result)) {
+    if ((flags & TAG_OBJECT) != 0) {
+      sub(Operand(result), Immediate(object_size - kHeapObjectTag));
+    } else {
+      sub(Operand(result), Immediate(object_size));
+    }
+  } else if ((flags & TAG_OBJECT) != 0) {
+    add(Operand(result), Immediate(kHeapObjectTag));
   }
-
-  // Update allocation top.
-  UpdateAllocationTopHelper(result_end, scratch);
 }
 
 
 void MacroAssembler::AllocateInNewSpace(int header_size,
                                         ScaleFactor element_size,
                                         Register element_count,
                                         Register result,
                                         Register result_end,
                                         Register scratch,
                                         Label* gc_required,
@@ skipping 899 matching lines @@
 
   // Check that the code was patched as expected.
   ASSERT(masm_.pc_ == address_ + size_);
   ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32