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Re: [RFC] Enabling loop unrolls at -O3?
Giovanni Bajo wrote:
If -O1 means "optimize, but be fast", what does -O2 mean? And what does -O3
mean? If -O2 means "the current set of optimizer that we put in -O2", that's
unsatisfying for me.
Right, that's exactly my point, you want some clear statement of the
goals of different levels, defining -On as merely being better
performance than -O(n+1) at the expense of worse compile time
is really not sufficient.
With large applications, it is often a big job to test out different
optimization levels, so this is not always the practical way of choosing.