Microoptimization to regexps.

src/mips/code-stubs-mips.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 5387 matching lines @@
   // v0: JSArray, tagged.
   // a3: FixedArray, tagged.
   // t1: Number of elements in array, untagged.
 
   // Set map.
   __ li(a2, Operand(masm->isolate()->factory()->fixed_array_map()));
   __ sw(a2, FieldMemOperand(a3, HeapObject::kMapOffset));
   // Set FixedArray length.
   __ sll(t2, t1, kSmiTagSize);
   __ sw(t2, FieldMemOperand(a3, FixedArray::kLengthOffset));
-  // Fill contents of fixed-array with the-hole.
-  __ li(a2, Operand(masm->isolate()->factory()->the_hole_value()));
+  // Fill contents of fixed-array with undefined.
+  __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
   __ Addu(a3, a3, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-  // Fill fixed array elements with hole.
+  // Fill fixed array elements with undefined.
   // v0: JSArray, tagged.
-  // a2: the hole.
+  // a2: undefined.
   // a3: Start of elements in FixedArray.
   // t1: Number of elements to fill.
   Label loop;
   __ sll(t1, t1, kPointerSizeLog2);  // Convert num elements to num bytes.
   __ addu(t1, t1, a3);  // Point past last element to store.
   __ bind(&loop);
   __ Branch(&done, ge, a3, Operand(t1));  // Break when a3 past end of elem.
   __ sw(a2, MemOperand(a3));
   __ Branch(&loop, USE_DELAY_SLOT);
   __ addiu(a3, a3, kPointerSize);  // In branch delay slot.
@@ skipping 2402 matching lines @@
   __ Pop(ra, t1, a1);
   __ Ret();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS