Richard Freeman <[EMAIL PROTECTED]> posted [EMAIL PROTECTED], excerpted below, on Fri, 18 Jul 2008 15:34:53 -0400:
> Personally, I use -Os across the board when it doesn't break. As you > said I tend to be memory/IO bound, and optimizing for size helps with > both (swapping causes IO). I'd probably benefit from using -O3 on the > aforementioned CPU-intensive apps. I did before gcc-4.3, but with 4.3, several of the other flags (-freorder- blocks-and-partition, for instance, which increases cache hit rates but also increases size) I was using folded into -O2 but not -Os, and I decided -O2 was a better choice as a result. Has anyone done a study of -Os vs -O2 with gcc-4.3.x, similar to the ICC/ gcc-4.x study linked upthread? On x86_64 would be an extra bonus, particularly if it were on AMD, or if both Intel and AMD were studied, as would the effect of such flags as -freorder-blocks-and-partition, as mentioned above. I'd love to see links, if so! -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- gentoo-dev@lists.gentoo.org mailing list
