[Bug ipa/114247] RISC-V: miscompile at -O3 and IPA SRA

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114247

--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Martin Jambor
<jamborm@gcc.gnu.org>:

https://gcc.gnu.org/g:44191982c6bd41db1c9d126ea2f15febec3c1f81

commit r12-10442-g44191982c6bd41db1c9d126ea2f15febec3c1f81
Author: Martin Jambor <mjambor@suse.cz>
Date:   Tue May 14 14:13:36 2024 +0200

    ipa: Force args obtined through pass-through maps to the expected type (PR
114247)

    Interactions of IPA-CP and IPA-SRA on the same data is a rather big
    source of issues, I'm afraid.  PR 113964 is a situation where IPA-CP
    propagates an unsigned short in a union parameter into a function
    which itself calls a different function which has a same union
    parameter and both these union parameters are split with IPA-SRA.  The
    leaf function however uses a signed short member of the union.

    In the calling function, we get the unsigned constant as the
    replacement for the union and it is then passed in the call without
    any type compatibility checks.  Apparently on riscv64 it matters
    whether the parameter is signed or unsigned short and so the leaf
    function can see different values.

    Fixed by using useless_type_conversion_p at the appropriate place and
    if it fails, use force_value_to type as elsewhere in similar
    situations.

    gcc/ChangeLog:

    2024-04-04  Martin Jambor  <mjambor@suse.cz>

            PR ipa/114247
            * ipa-param-manipulation.cc (ipa_param_adjustments::modify_call):
            Force values obtined through pass-through maps to the expected
            split type.

    gcc/testsuite/ChangeLog:

    2024-04-04  Patrick O'Neill  <patrick@rivosinc.com>
                Martin Jambor  <mjambor@suse.cz>

            PR ipa/114247
            * gcc.dg/ipa/pr114247.c: New test.

    (cherry picked from commit 8cd0d29270d4ed86c69b80c08de66dcb6c1e22fe)