icpc avx optimization

icpc avx optimization

Hi,

      The intel C++ compiler icpc provides following flags for using AVX:

       -xAVX,  -xavx,  -mavx

      which one should be used and which is more effective?

Thanks

2 posts / 0 new
Last post
For more complete information about compiler optimizations, see our Optimization Notice.

If both -xAVX and -xavx are accepted, they would be the same. -mavx differs in that there is no run-time check to see whether the program you have built is running on a recognized Intel AVX platform, so instead of a message about incompatibility you would see illegal instruction fault on a non-AVX platform.
Among the ways you could check is to generate asm files (option -S) and compare to see that the generated code is the same. As far as I know, differences could be taken as evidence of a bug.
Any of the available options will run on an Intel AVX platform, but in most cases the AVX code should run as fast or faster than the backward compatible options.

Leave a Comment

Please sign in to add a comment. Not a member? Join today