public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "bergner at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined Date: Fri, 03 Dec 2021 18:52:22 +0000 [thread overview] Message-ID: <bug-103548-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548 Bug ID: 103548 Summary: Identical MMA assemble quads are incorrectly combined Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: bergner at gcc dot gnu.org Target Milestone: --- We incorrectly combine multiple identical build/assemble quads/accs leading to incorrect assembly being generated: typedef unsigned char vec_t __attribute__((vector_size(16))); void foo (__vector_quad *dst, vec_t *src) { __vector_quad quad0, quad1; /* Adjacent loads should be combined into two lxvp instructions. and identical build accs should not be combined. */ __builtin_mma_build_acc (&quad0, src[0], src[1], src[2], src[3]); __builtin_mma_build_acc (&quad1, src[0], src[1], src[2], src[3]); dst[0] = quad0; dst[2] = quad1; } ...gives: lxv 3,0(4) lxv 2,16(4) lxv 1,32(4) lxv 0,48(4) xxmtacc 0 xxmfacc 0 stxvp 2,0(3) stxvp 0,32(3) xxmfacc 0 stxvp 2,128(3) stxvp 0,160(3) blr Notive we only have 4 loads and 1 xxmtacc but 2 xxmfacc. This is incorrect. I have a patch I'm testing. Note that for build/assemble pair, we are allowed to combine identical calls...amd we do.
next reply other threads:[~2021-12-03 18:52 UTC|newest] Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-12-03 18:52 bergner at gcc dot gnu.org [this message] 2021-12-03 19:45 ` [Bug target/103548] " bergner at gcc dot gnu.org 2021-12-14 21:00 ` cvs-commit at gcc dot gnu.org 2021-12-14 23:19 ` bergner at gcc dot gnu.org 2022-05-06 8:32 ` jakub at gcc dot gnu.org 2023-05-08 12:23 ` rguenth at gcc dot gnu.org
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=bug-103548-4@http.gcc.gnu.org/bugzilla/ \ --to=gcc-bugzilla@gcc.gnu.org \ --cc=gcc-bugs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).