"David Mathog" <mat...@caltech.edu> writes: > I compiled that with a target program and gprof showed > all the time in resulting binary in the inlined functions. It ran about > 4X slower than the SSE2 hardware version, which is about what I > expected. So, so far so good. What I am worried about now is that > since it was invoked with "-msse2" the compiler may still be generating > SSE2 calls within the inlined functions. Is there a way to definitively > disable this but still retain -msse2 on the command line?
No. If I understand what you are doing, I don't think you want to use -msse2 at all. In fact I think you want -mno-sse2. > Actually, one thing I was never very clear on, do -msse2 -m3dnow > etc. only provide access to the corresponding machine operations through > the _mm* (or whatever) definitions in the header file, or does the > compiler also figure out vector operations by itself during the > optimization phase of compilation? The latter: the compiler also figures out vector operations by itself, particularly if you use the -ftree-vectorize option. Ian
