[Bug testsuite/59494] [4.9 Regression] FAIL: gfortran.dg/vect/fast-math-mgrid-resid.f scan-tree-dump-times optimized "vect_[^\\n]*\\+ " 13

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59494

--- Comment #4 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
> I believe that is the only reason for the different number of vector additions.

I don't think the number of packed double operations is changed, only the
number of occurrences of the scanned regular expression:

[Book15] f90/bug% gfc -S -mtune=generic -O3 -ffast-math -msse2
-fpredictive-commoning -ftree-vectorize -fdump-tree-optimized
/opt/gcc/work/gcc/testsuite/gfortran.dg/vect/fast-math-mgrid-resid.f
[Book15] f90/bug% egrep "vect_[^\n]*\+ " fast-math-mgrid-resid.f.169t.optimized
| wc -l
      13
[Book15] f90/bug% grep addpd fast-math-mgrid-resid.s | wc -l                  
23
[Book15] f90/bug% grep subpd fast-math-mgrid-resid.s | wc -l                   
                       4
[Book15] f90/bug% grep mulpd fast-math-mgrid-resid.s | wc -l
4
[Book15] f90/bug% gfc -S -O3 -ffast-math -msse2 -fpredictive-commoning
-ftree-vectorize -fdump-tree-optimized
/opt/gcc/work/gcc/testsuite/gfortran.dg/vect/fast-math-mgrid-resid.f
[Book15] f90/bug% egrep "vect_[^\n]*\+ " fast-math-mgrid-resid.f.169t.optimized
| wc -l
      10
[Book15] f90/bug% grep addpd fast-math-mgrid-resid.s | wc -l
23
[Book15] f90/bug% grep subpd fast-math-mgrid-resid.s | wc -l
4
[Book15] f90/bug% grep mulpd fast-math-mgrid-resid.s | wc -l
4

> Well, I don't think configuring with arbitrary --with-cpu/tune is 
> a supported configuration for zero testsuite FAILs ...?

The tested configurations x86_64-apple-darwin* (IIRC defaulting to
--with-arch=core2 --with-cpu=core2) and x86_64-*-* configured with
--with-arch=corei7 --with-cpu=corei7. I also hope forbidden configurations are
rejected (as done for at least some compiling options).