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[Bug tree-optimization/37525] [4.4 Regression] IVOPTS difference causing 20% degradation in 173.applu benchmark



------- Comment #1 from jakub at gcc dot gnu dot org  2008-09-17 15:12 -------
I guess the problem might be that Fortran has signed size_type_node (and
unsigned
sizetype), so what the newly added code in int_fits_type_p does breaks Fortran
assumptions.  Say for sizetype -25 (i.e. unsigned value), when it is
force_fit_type_double into a signed type, it becomes signed -25, and given that
type_low_bound (of sizetype) is 0 and -25 is smaller than 0, int_fits_type_p
fails.
Perhaps just adding another TYPE_UNSIGNED (size_type_node) check to the if
would be sufficient.
That said, I still think such change isn't appropriate for 4.3 branch.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dodji at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37525


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