Monthly Archives: November 2011

The Generic SSE2 Loop

In response to a couple of comments on my post about find-first-bit-set in SSE2 registers, amounting to “what use is a routine that only does 16-byte bitvecs”, I thought I’d post the canonic, generic loop through memory using SSE2 ops. … Continue reading

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SSE2 bit trick: ffs/fls for XMM registers

For the full “C” code that uses this idea for an arbitrary-length byte vector, see this later blog post In a discussion about all the wonderful uses of the combination movemask(pcmpxx(a,b)), it occurred to me that this gives you a … Continue reading

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