On Mon, 2013-11-11 at 15:34 -0800, H. Peter Anvin wrote: > On 11/10/2013 06:22 PM, Joe Perches wrote: > > > > Perhaps the current x86 bitops asm code is being conflated > > with the ideal implementation? > > > Yes, by you. Really? I don't think so. How does the use of signed long for an index where no negative values are possible or the use of a negative int for BIT_MASK make sense? > x86 has instructions that operate on signed bitindicies. indices. > It doesn't > have instructions that operate on unsigned bitindicies. Unless someone > is willing to do the work to prove that shift and mask is actually > faster than using the hardware instructions (which I doubt, but it is > always a possibility), that's what we have. That doesn't mean x86 is the ideal implementation. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
