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[Bug middle-end/40106] [4.4/4.5 Regression] Weird interaction between optimize_insn_for_speed_p and -funsafe-math-optimizations



------- Comment #49 from dominiq at lps dot ens dot fr  2010-03-19 15:40 -------
A few remarks about comments #47 and #48

> Note that this PR isn't too serious as -fwhole-file isn't the default
> for Fortran so we do not run into this unfortunate interaction of
> profile estimation and inlining.

The test in comment #31 shows that you don't need -fwhole-file nor inlining to
trigger this PR.

> +             || (n == 2

Isn't it n==3?

I have done some tests of replacing 1.5 in the test in comment #31 with some
other values (up to 15.5, but not in a systematic way). On
x86_64-apple-darwin10, the multiplications are always a win for size (based on
the size of a.out) over the call to pow. Is my metric flawed? If yes, what
should I use? If no could embedded system experts have a look at this kind of
optimization?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40106


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