[Bug rtl-optimization/60473] optimization after shift sub-optimal

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60473

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Roger Sayle <sayle@gcc.gnu.org>:

https://gcc.gnu.org/g:76eafcc395d2bcd4147cb1ba1a8aff321571402f

commit r11-2551-g76eafcc395d2bcd4147cb1ba1a8aff321571402f
Author: Roger Sayle <roger@nextmovesoftware.com>
Date:   Tue Aug 4 16:56:06 2020 +0100

    Test case for PR rtl-optimization/60473

    PR rtl-optimization/60473 is code quality regression that has
    been cured by improvements to register allocation.  For the function
    in the test case, GCC 4.4, 4.5 and 4.6 generated very poor code
    requiring two mov instructions, and GCC 4.7 and 4.8 (when the PR was
    filed) produced better but still poor code with one mov instruction.
    Since GCC 4.9 (including current mainline), it generates optimal
    code with no mov instructions, matching what used to be generated
    in GCC 4.1.

    2020-08-04  Roger Sayle  <roger@nextmovesoftware.com>

    gcc/testsuite/ChangeLog
            PR rtl-optimization/60473
            * gcc.target/i386/pr60473.c: New test.