[Bug target/58529] GCC -funroll-loops 150% slower with -march=native on x86-64

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58529

--- Comment #10 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Playing around with --param max-unroll-times= gives:

0        real    0m1.499s        user    0m1.497s        sys     0m0.000s
1        real    0m1.492s        user    0m1.490s        sys     0m0.000s
2        real    0m1.138s        user    0m1.137s        sys     0m0.000s
3        real    0m1.146s        user    0m1.144s        sys     0m0.000s
4        real    0m0.932s        user    0m0.930s        sys     0m0.001s
5        real    0m0.955s        user    0m0.953s        sys     0m0.000s
6        real    0m0.934s        user    0m0.933s        sys     0m0.000s
7        real    0m0.934s        user    0m0.932s        sys     0m0.001s
8        real    0m2.480s        user    0m2.477s        sys     0m0.000s
9        real    0m2.481s        user    0m2.479s        sys     0m0.000s
10       real    0m2.482s        user    0m2.478s        sys     0m0.001s
11       real    0m2.480s        user    0m2.477s        sys     0m0.000s
12       real    0m2.477s        user    0m2.474s        sys     0m0.000s