   SSE/SSE2 Clock Cycle Count
  Is there a list of the SSE\SSE2 instruction set with the number of clock cycles used by that instruction?I can''t find it with google and need it to see which of the functions is faster without benchmarking it (inreliable). 
  Cycle counting has been misleading and a waste of time since the 286. With modern deep parallel pipeline CPUs it is an even bigger waste of time. Don''t try and construct "fast" code on paper by refering to a cycle count table and using the instructions with the smallest cycle sum. The number of cycles it will take to complete an instruction in the real world is far, far more complex then a simple lookup table. Write real code and profile it, otherwise all your conclusions will be worth less than the bytes of harddrive space they occupy. ;  http://www.cpuid.com/sse.php ;  Michaelson, it''s certainly true that code execution time != sum of instruction latencies, but such a reference is very useful. Some instructions are just slow on a particular processor (especially on Athlons, with vector-path decode), and going all-out includes perfect ordering of your dependency chains (yes, even with huge reorder buffers, this makes a difference). Sure, you will need to know other limitations than instruction issue rate and latency, but you don''t get anywhere without such a table.AMD''s Athlon optimization guide has a list of all instructions, but the timings are completely different than the P IV (and Athlons don''t support SSE2).Good link, thanks!p.s. perhaps by profiler Michalson means one that simulates the CPU pipes, telling you the actual # of cycles something took, as opposed to basic time-based profilers. That is also good, but it''s better to have a reference. ;  Is there also a list of fpu (fadd, fmul, fld, etc.) instructions? ;quote:Original post by Jan Wassenberg  AMD''s Athlon optimization guide has a list of all instructions, but the timings are completely different than the P IV (and Athlons don''t support SSE2).Apart from the Athlon64 based chips which do ;  When I say Athlon, I mean Athlon, not Athlon64 hmm, I''ve got to get me one of those.. 