Refactor and improve inlined double-aligned allocations

src/ia32/code-stubs-ia32.cc

 // Copyright 2012 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 322 matching lines @@
   int elements_size = 0;
   if (length > 0) {
     elements_size = mode == FastCloneShallowArrayStub::CLONE_DOUBLE_ELEMENTS
         ? FixedDoubleArray::SizeFor(length)
         : FixedArray::SizeFor(length);
   }
   int size = JSArray::kSize + elements_size;
 
   // Allocate both the JS array and the elements array in one big
   // allocation. This avoids multiple limit checks.
-  __ AllocateInNewSpace(size, eax, ebx, edx, fail, TAG_OBJECT);
+  AllocationFlags flags = TAG_OBJECT;
+  if (mode == FastCloneShallowArrayStub::CLONE_DOUBLE_ELEMENTS) {
+    flags = static_cast<AllocationFlags>(DOUBLE_ALIGNMENT | flags);
+  }
+  __ AllocateInNewSpace(size, eax, ebx, edx, fail, flags);
 
   // Copy the JS array part.
   for (int i = 0; i < JSArray::kSize; i += kPointerSize) {
     if ((i != JSArray::kElementsOffset) || (length == 0)) {
       __ mov(ebx, FieldOperand(ecx, i));
       __ mov(FieldOperand(eax, i), ebx);
     }
   }
 
   if (length > 0) {
@@ skipping 3718 matching lines @@
   __ JumpIfNotSmi(ebx, &slowcase);
   __ cmp(ebx, Immediate(Smi::FromInt(kMaxInlineLength)));
   __ j(above, &slowcase);
   // Smi-tagging is equivalent to multiplying by 2.
   STATIC_ASSERT(kSmiTag == 0);
   STATIC_ASSERT(kSmiTagSize == 1);
   // Allocate RegExpResult followed by FixedArray with size in ebx.
   // JSArray:   [Map][empty properties][Elements][Length-smi][index][input]
   // Elements:  [Map][Length][..elements..]
   __ AllocateInNewSpace(JSRegExpResult::kSize + FixedArray::kHeaderSize,
-                        times_half_pointer_size,
-                        ebx,  // In: Number of elements (times 2, being a smi)
+                        times_pointer_size,
+                        ebx,  // In: Number of elements as a smi
+                        REGISTER_VALUE_IS_SMI,
                         eax,  // Out: Start of allocation (tagged).
                         ecx,  // Out: End of allocation.
                         edx,  // Scratch register
                         &slowcase,
                         TAG_OBJECT);
   // eax: Start of allocated area, object-tagged.
 
   // Set JSArray map to global.regexp_result_map().
   // Set empty properties FixedArray.
   // Set elements to point to FixedArray allocated right after the JSArray.
@@ skipping 3376 matching lines @@
   // Restore ecx.
   __ pop(ecx);
   __ ret(0);
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32