[Bug middle-end/81376] unnecessary cast before comparison

[ygribov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81376

--- Comment #4 from Yury Gribov <ygribov at gcc dot gnu.org> ---
Author: ygribov
Date: Fri Oct 12 20:35:20 2018
New Revision: 265131

URL: https://gcc.gnu.org/viewcvs?rev=265131&root=gcc&view=rev
Log:
Add pattern to remove useless float casts in comparisons.

        PR middle-end/81376

        gcc/
        * real.c (format_helper::can_represent_integral_type_p): New function
        * real.h (format_helper::can_represent_integral_type_p): Ditto.
        * match.pd: New pattern.

        gcc/testsuite/
        * c-c++-common/pr81376.c: New test.
        * gcc.target/i386/387-ficom-2.c: Update test.
        * gcc.target/i386/387-ficom-2.c: Ditto.

Added:
    trunk/gcc/testsuite/c-c++-common/pr81376.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/match.pd
    trunk/gcc/real.c
    trunk/gcc/real.h
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.target/i386/387-ficom-1.c
    trunk/gcc/testsuite/gcc.target/i386/387-ficom-2.c