[Bug tree-optimization/110271] [14 Regression] UICE on pycryptodome-3.17.0 during GIMPLE pass: widening_mul: in gsi_replace, at gimple-iterator.cc:437

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110271

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:5b67116a85298bbe358b036d34ad23119cebbdac

commit r14-1895-g5b67116a85298bbe358b036d34ad23119cebbdac
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Jun 16 19:46:36 2023 +0200

    tree-ssa-math-opts: Fix up uaddc/usubc pattern matching [PR110271]

    The following testcase ICEs, because I misremembered what the return value
    from match_arith_overflow is.  It isn't true if __builtin_*_overflow was
    matched, but it is true only in the BIT_NOT_EXPR case if stmt was removed.

    So, if match_arith_overflow matches something, gsi_stmt (gsi) will not
    be stmt and match_uaddc_usubc will be confused and can ICE.

    The following patch fixes it by checking if gsi_stmt (gsi) == stmt,
    in that case we know it is still a PLUS_EXPR/MINUS_EXPR and we can try to
    pattern match it further as UADDC/USUBC.

    2023-06-16  Jakub Jelinek  <jakub@redhat.com>

            PR tree-optimization/110271
            * tree-ssa-math-opts.cc (math_opts_dom_walker::after_dom_children)
            <case PLUS_EXPR>: Ignore return value from match_arith_overflow,
            instead call match_uaddc_usubc only if gsi_stmt (gsi) is still
stmt.

            * gcc.c-torture/compile/pr110271.c: New test.