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Re: [RFC] Enabling loop unrolls at -O3?
Giovanni Bajo wrote:
Steven Bosscher <stevenb@suse.de> wrote:
I guess the issue is what does "huge" mean, it is hard to discuss based
on loaded adjectives taking the place of data :-)
Huge here means 15-20% on x86* hosts.
I don't consider this huge for -O3. I think -O3 can be slower if it achieves
better code, and -funroll-loops makes it do just that.
I would certainly agree, I am not sure I even find it huge for -O2.
After all 20% compile time represents a couple of months advance
in computer hardware (and that is true across the board, even if
you are talking about upgrading 1990 hardware to 1991 hardware :-))