[Bug target/93141] Missed optimization : Use of adc when checking overflow

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93141

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Thu Jan  9 08:18:51 2020
New Revision: 280029

URL: https://gcc.gnu.org/viewcvs?rev=280029&root=gcc&view=rev
Log:
        PR target/93141
        * config/i386/i386.md (subv<mode>4): Use SWIDWI iterator instead of
        SWI.  Use <general_hilo_operand> instead of <general_operand>.  Use
        CONST_SCALAR_INT_P instead of CONST_INT_P.
        (*subv<mode>4_1): Rename to ...
        (subv<mode>4_1): ... this.
        (*subv<dwi>4_doubleword, *addv<dwi>4_doubleword_1): New
        define_insn_and_split patterns.
        (*subv<mode>4_overflow_1, *addv<mode>4_overflow_2): New define_insn
        patterns.

        * gcc.target/i386/pr93141-1.c: Add tests with constants that have MSB
        of the low half of the constant set.
        * gcc.target/i386/pr93141-2.c: New test.

Added:
    trunk/gcc/testsuite/gcc.target/i386/pr93141-2.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/i386.md
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.target/i386/pr93141-1.c