[Bug tree-optimization/110199] [12/13/14 Regression] Missing VRP transformation with MIN_EXPR and known relation

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110199

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jeff Law <law@gcc.gnu.org>:

https://gcc.gnu.org/g:8fe27ed193d60f6cd8b34761858a720c95eabbdb

commit r14-9419-g8fe27ed193d60f6cd8b34761858a720c95eabbdb
Author: jlaw <jeffreyalaw@gmail.com>
Date:   Sun Mar 10 11:58:00 2024 -0600

    [committed] [PR tree-optimization/110199] Simplify MIN/MAX more often

    So as I mentioned in the BZ, the case of

    t = MIN_EXPR (A, B)

    where we know something about the relationship between A and B can be
trivially
    handled by some existing code in DOM.  That existing code would simplify
when A
    == B.  But by testing GE and LE instead of EQ we can cover more cases with
    minimal effort.  When applicable the MIN/MAX turns into a simple copy.

    I made one other change.  We have other binary operations that we simplify
when
    we know something about the relationship between the operands.  That code
was
    not canonicalizing the order of operands when building the expression to
lookup
    in the hash tables to discover that relationship.  Since those paths are
only
    testing for equality, we can trivially reverse them and not have to worry
about
    changing codes or anything like that.  So extremely safe and avoids having
to
    come back and fix that code to match the MIN_EXPR/MAX_EXPR case later.

    Bootstrapped on x86 and also tested on the crosses.  I briefly thought
there
    was an sh regression, but that was actually the recent fwprop changes
twiddling
    code generation for one test.

            PR tree-optimization/110199
    gcc/
            * tree-ssa-scopedtables.cc
            (avail_exprs_stack::simplify_binary_operation): Generalize handling
            of MIN_EXPR/MAX_EXPR to allow additional simplifications. 
Canonicalize
            comparison operands for other cases.

    gcc/testsuite

            * gcc.dg/tree-ssa/minmax-27.c: New test.
            * gcc.dg/tree-ssa/minmax-28.c: New test.