Certain program have support for either of these extentions. The program will most likely use the best one for the job.
They can be mutually exclusive, however, if you use the CFLAG -mfpmath=sse,387. As far as I know it, it will try to use SSE instructions for math where possible, in detriment of using the 387 math co-processor. But this only get any advantage when using AMD64 processors. I never tested it, I just copied what the Gentoo Wiki says about it. ;P 2006/1/12, Willie Wong <[EMAIL PROTECTED]>: > On Thu, Jan 12, 2006 at 03:09:40PM -0700, Penguin Lover Tom Smith squawked: > > Are these flags mutually exclusive? > > > > I know, for example, that if I have a Pentium II that the MMX flag > > should apply while the sse and sse2 flags would not. > > > > But what if I have a Pentium III or IV? Would I only use the most recent > > "optimization" or do I need to add all three to take advantage of each one? > > > > I checked the USE flag descriptions and there wasn't anything indicating > > indicating whether the can or should be used together. > > > Not quite sure how it works officially. But I run a Pentium IV, and I > have mmx mmxext sse sse2 enabled, so they are at least NOT mutually > exclusive. > > W > -- > All science is either physics or stamp collecting. > ~Ernest Rutherford > Sortir en Pantoufles: up 61 days, 15:40 > -- > gentoo-user@gentoo.org mailing list > > -- gentoo-user@gentoo.org mailing list
