Cleanup: use xorps to zero out an xmm register on ia32 too.

src/ia32/disasm-ia32.cc

-// Copyright 2007-2008 the V8 project authors. All rights reserved.
+// Copyright 2011 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
 //       with the distribution.
@@ skipping 962 matching lines @@
             AppendToBuffer("%s", f0mnem);
             data += 2;
           } else if (f0byte == 0x28) {
             data += 2;
             int mod, regop, rm;
             get_modrm(*data, &mod, &regop, &rm);
             AppendToBuffer("movaps %s,%s",
                            NameOfXMMRegister(regop),
                            NameOfXMMRegister(rm));
             data++;
+          } else if (f0byte == 0x57) {
+            data += 2;
+            int mod, regop, rm;
+            get_modrm(*data, &mod, &regop, &rm);
+            AppendToBuffer("xorps %s,%s",
+                           NameOfXMMRegister(regop),
+                           NameOfXMMRegister(rm));
+            data++;
           } else if ((f0byte & 0xF0) == 0x80) {
             data += JumpConditional(data, branch_hint);
           } else if (f0byte == 0xBE || f0byte == 0xBF || f0byte == 0xB6 ||
                      f0byte == 0xB7 || f0byte == 0xAF) {
             data += 2;
             data += PrintOperands(f0mnem, REG_OPER_OP_ORDER, data);
           } else if ((f0byte & 0xF0) == 0x90) {
             data += SetCC(data);
           } else if ((f0byte & 0xF0) == 0x40) {
             data += CMov(data);
@@ skipping 617 matching lines @@
       fprintf(f, "  ");
     }
     fprintf(f, "  %s\n", buffer.start());
   }
 }
 
 
 }  // namespace disasm
 
 #endif  // V8_TARGET_ARCH_IA32