[Bug fortran/53950] [4.7/4.8/4.9 Regression] 1.5 times slowdown from 4.4.0 to 4.7.0 with -m32

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53950

Dominique d'Humieres <dominiq at lps dot ens.fr> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW
            Summary|1.5 times slowdown from     |[4.7/4.8/4.9 Regression]
                   |4.4.0 to 4.7.0              |1.5 times slowdown from
                   |                            |4.4.0 to 4.7.0 with -m32

--- Comment #5 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
On a Core2Duo 2.5Ghz under x86_64-apple-darwin10, I get

            -m64           -m32
4.9.0    1.9743720      2.2397862
4.8.1    2.0542710      2.2539010
4.7.3    1.9538360      2.2104399
4.6.4    1.9587610      2.1613581
4.5.4    2.0137279      2.3153970
4.4.7    1.9963471      1.9965631

Note that with 4.8 and trunk, I had to change slightly the code otherwise the
loop is optimized out.