------- Comment #3 from burnus at gcc dot gnu dot org 2006-11-30 18:54 ------- Created an attachment (id=12717) --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=12717&action=view) icc -O3 -xW -S of only the function eos()
> but I think what ICC does is only calculates CS[1] instead of all of CS[i]. I don't think so. If I use: for(j = 0; j < NODES; j++) { CGAMMA = CGAMMA + CS[j]; } rather than CGAMMA = CGAMMA + CS[1]; the timings don't change. I also didn't include -ip or -ipo (inter process analysis). With this change: icc 0m2.324s; gcc 0m7.194s. > Also you are using VLAs so maybe ICC also converts those VLAs to normal > arrays. You might also want to add "-mfpmath=sse,387". This does not really help: gcc 0m7.066s -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30032