[Bug middle-end/112679] ICE in expand_float, at optabs.cc:5724 with bitint

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112679

--- Comment #2 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:31669ec1d01c93fb0a63a7053ad314c17fa5a416

commit r14-5818-g31669ec1d01c93fb0a63a7053ad314c17fa5a416
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Nov 24 11:30:30 2023 +0100

    lower-bitint: Lower FLOAT_EXPR from BITINT_TYPE INTEGER_CST [PR112679]

    The bitint lowering pass only does something if it sees BITINT_TYPE
(medium,
    large, huge) SSA_NAMEs.  In the past I've already ran into one special case
    where the above doesn't work well, if there is a store of medium/large/huge
    BITINT_TYPE INTEGER_CST into memory, there might not be any BITINT_TYPE
    SSA_NAMEs in the function, yet we need to lower.  This has been solved by
    also checking for SSA_NAME_IS_VIRTUAL_OPERAND if at the vdef there isn't
    such a store (the whole intent is make the pass as cheap as possible in the
    currently very likely case that the IL doesn't have any BITINT_TYPEs at
    all).
    And the following testcase shows a similar problem.  With -frounding-math
    we don't fold some of FLOAT_EXPRs with INTEGER_CST operands, and if those
    INTEGER_CSTs are medium/large/huge BITINT_TYPEs, we need to either cast
    the INTEGER_CST to corresponding INTEGER_TYPE (for medium) or lower to
    internal fn call which is later turned into libgcc call (for large/huge).
    The following patch does that, but of course admittedly this discovery
    of stores and FLOAT_EXPRs means we already look through quite a few
    SSA_NAME_DEF_STMTs even when BITINT_TYPEs never appear.

    2023-11-23  Jakub Jelinek  <jakub@redhat.com>

            PR middle-end/112679
            * gimple-lower-bitint.cc (gimple_lower_bitint): Also stop first
loop on
            floating point SSA_NAME set in FLOAT_EXPR assignment from
BITINT_TYPE
            INTEGER_CST.  Set has_large_huge for those if that BITINT_TYPE is
large
            or huge.  Set kind to such FLOAT_EXPR assignment rhs1 BITINT_TYPE's
kind.

            * gcc.dg/bitint-42.c: New test.