[Bug target/109547] [13] RISC-V: Multiple vsetvli for load/store loop

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109547

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Kito Cheng <k...@gcc.gnu.org>:

https://gcc.gnu.org/g:98fc9d38db95b3396a8540accc1bc45e71080650

commit r13-7386-g98fc9d38db95b3396a8540accc1bc45e71080650
Author: Juzhe-Zhong <juzhe.zh...@rivai.ai>
Date:   Fri Apr 7 09:34:13 2023 +0800

    RISC-V: Add local user vsetvl instruction elimination [PR109547]

    This patch is to enhance optimization for auto-vectorization.

    Before this patch:

    Loop:
    vsetvl a5,a2...
    vsetvl zero,a5...
    vle

    After this patch:

    Loop:
    vsetvl a5,a2
    vle

    gcc/ChangeLog:

            PR target/109547
            * config/riscv/riscv-vsetvl.cc (local_eliminate_vsetvl_insn): New
function.
            (vector_insn_info::skip_avl_compatible_p): Ditto.
            (vector_insn_info::merge): Remove default value.
            (pass_vsetvl::compute_local_backward_infos): Ditto.
            (pass_vsetvl::cleanup_insns): Add local vsetvl elimination.
            * config/riscv/riscv-vsetvl.h: Ditto.

    gcc/testsuite/ChangeLog:

            PR target/109547
            * gcc.target/riscv/rvv/vsetvl/pr109547.c: New.
            * gcc.target/riscv/rvv/vsetvl/vsetvl-17.c: Update scan
            condition.

    (cherry picked from commit d51f2456ee51bd59a79b4725ca0e488c25260bbf)