[Bug target/105504] Fails to break dependency for vcvtss2sd xmm, xmm, mem

cvs-commit at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Wed Jun 8 03:24:53 GMT 2022


--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by hongtao Liu <liuhongt@gcc.gnu.org>:


commit r13-1009-g5e005393d4ff0a428c5f55b9ba7f65d6078a7cf5
Author: liuhongt <hongtao.liu@intel.com>
Date:   Mon May 30 15:30:51 2022 +0800

    Disparages SSE_REGS alternatives sligntly with ?v instead of *v in

    So alternative v won't be igored in record_reg_classess.

    Similar for *r alternatives in some vector patterns.

    It helps testcase in the PR, also RA now makes better decisions for

            movd    %esi, %xmm0
            movd    %edi, %xmm1
    -       movl    %esi, -12(%rsp)
            paddd   %xmm0, %xmm1
            pinsrd  $0, %esi, %xmm0
            paddd   %xmm1, %xmm0

    The patch has no big impact on SPEC2017 for both O2 and Ofast
    march=native run.

    And I noticed there's some changes in SPEC2017 from code like

    mov mem, %eax
    vmovd %eax, %xmm0
    mov %eax, 64(%rsp)


    vmovd mem, %xmm0
    vmovd %xmm0, 64(%rsp)

    Which should be exactly what we want?


            PR target/105513
            PR target/105504
            * config/i386/i386.md (*movsi_internal): Change alternative
            from *v to ?v.
            (*movdi_internal): Ditto.
            * config/i386/sse.md (vec_set<mode>_0): Change alternative *r
            to ?r.
            (*vec_extractv4sf_mem): Ditto.
            (*vec_extracthf): Ditto.


            * gcc.target/i386/pr105513-1.c: New test.
            * gcc.target/i386/extract-insert-combining.c: Add new
            scan-assembler-not for spill.

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