On 02/09/2012 10:20 AM, xunxun wrote: > I use the code main.c (test sin speed) > > On Win7 64bit, gcc 4.6.2 32bit > > gcc -O3 -ffast-math main.c -o main.exe > > run main.exe will cost 6.853s. > > When linking with intel libM no fastmath > > gcc -O3 main.c -o main.exe libmmt.lib libircmt.lib > > run main.exe will cost 4.367s. Ah okay, I get it now, its sin, not exp. I suspect that it's the argument reduction step that's slowing you down. Andrew.
