* Jan Beulich <[EMAIL PROTECTED]> wrote: > This generally allows better code to be generated, since the zero- > extension during 32-bit operations comes for free (needed when the > result is used as array index or similar), whereas sign extension must > be done explicitly and frequently requires a one byte larger > instruction due to the necessary rex64 prefix.
good catch! Applied your patch to x86.git - queued it up for v2.6.25. I bet there are tons of other instances where we use signed instead of unsigned and get worse code generation. Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/