[Bug target/121787] [Trunk] RISC-V rv64gcv: crash at -O1/2/3

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121787

--- Comment #4 from Jeffrey A. Law <law at gcc dot gnu.org> ---
One of Avinash's recent changes seems to have made this go latent.  But I don't
think it really fixed whatever the underlying issue is.


commit 7d966cc35ad01d70cd9bfb6f531c938a7b6110b7
Author: Avinash Jayakar <avinashd@linux.ibm.com>
Date:   Sat Nov 8 09:57:59 2025 +0530

    isel: Check bounds before converting VIEW_CONVERT to VEC_SET.

    The function gimple_expand_vec_set_expr in the isel pass, converted
    VIEW_CONVERT_EXPR to VEC_SET_EXPR without checking the bounds on the index,
    which cause ICE on targets that supported VEC_SET_EXPR like x86 and
powerpc.
    This patch adds a bound check on the index operand and rejects the
conversion
    if index is out of bound.

    2025-11-08  Avinash Jayakar  <avinashd@linux.ibm.com>

    gcc/ChangeLog:
            PR tree-optimization/122126
            * gimple-isel.cc (gimple_expand_vec_set_extract_expr): Add bound
check.