Galloth <[EMAIL PROTECTED]> writes: > I want ask, if there is posibilities that gcc will be automaticaly > generates MMX instruction? I tried -mtune, -march -mmmx. But gcc stil > generates code without MMX instruction. On net I found only > information about inline assembler function or citation from man page. > I tried to compile program for adding two arrays of 24 chars.
This question is appropriate for the mailing list [EMAIL PROTECTED], not for [EMAIL PROTECTED] Please take any follow-ups to gcc-help. Thanks. In some cases gcc may be able to automatically generate MMX instructions if you use the -ftree-vectorize option. Otherwise, you need to write your code using the macros defined in the header file mmintrin.h. This can be found in the gcc source code in gcc/config/i386/mmintrin.h. It will also be installed with gcc somewhere on your system. It implements an interface documented by Intel; the documentation is available somewhere on the Intel web site. Ian
