[Bug target/116512] [12/13/14/15 Regression] vzeroupper emitted even though the upper half of the z registers are returned

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116512

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

https://gcc.gnu.org/g:6585b06303d8fd9da907f443fc0da9faed303712

commit r12-10694-g6585b06303d8fd9da907f443fc0da9faed303712
Author: liuhongt <hongtao....@intel.com>
Date:   Thu Aug 29 11:39:20 2024 +0800

    Check avx upper register for parallel.

    For function arguments/return, when it's BLK mode, it's put in a
    parallel with an expr_list, and the expr_list contains the real mode
    and registers.
    Current ix86_check_avx_upper_register only checked for SSE_REG_P, and
    failed to handle that. The patch extend the handle to each subrtx.

    gcc/ChangeLog:

            PR target/116512
            * config/i386/i386.cc (ix86_check_avx_upper_register): Iterate
            subrtx to scan for avx upper register.
            (ix86_check_avx_upper_stores): Inline old
            ix86_check_avx_upper_register.
            (ix86_avx_u128_mode_needed): Ditto, and replace
            FOR_EACH_SUBRTX with call to new
            ix86_check_avx_upper_register.

    gcc/testsuite/ChangeLog:

            * gcc.target/i386/pr116512.c: New test.

    (cherry picked from commit ab214ef734bfc3dcffcf79ff9e1dd651c2b40566)