Custom call IC for Math.floor.

src/ia32/disasm-ia32.cc

 // Copyright 2007-2008 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 1138 matching lines @@
             data += PrintRightOperand(data);
             AppendToBuffer(",%s", NameOfXMMRegister(regop));
           } else if (*data == 0xEF) {
              data++;
              int mod, regop, rm;
              get_modrm(*data, &mod, &regop, &rm);
              AppendToBuffer("pxor %s,%s",
                             NameOfXMMRegister(regop),
                             NameOfXMMRegister(rm));
              data++;
+          } else if (*data == 0x73) {
+             data++;
+             int mod, regop, rm;
+             get_modrm(*data, &mod, &regop, &rm);
+             int8_t imm8 = *reinterpret_cast<int8_t*>(data + 1);

[Erik Corry, 2010/09/20 11:56:50]

Why not just:
int imm8 = data[1];
?

[Vitaly Repeshko, 2010/09/21 12:54:49]

Almost done. I left static_cast there to avoid unsigned to signed warnings.

+             AppendToBuffer("psllq %s,%d",
+                            NameOfXMMRegister(rm),
+                            static_cast<int>(imm8));
+             data += 2;;
           } else {
             UnimplementedInstruction();
           }
         } else {
           UnimplementedInstruction();
         }
         break;
 
       case 0xFE:
         { data++;
@@ skipping 294 matching lines @@
       fprintf(f, "  ");
     }
     fprintf(f, "  %s\n", buffer.start());
   }
 }
 
 
 }  // namespace disasm
 
 #endif  // V8_TARGET_ARCH_IA32