public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "vineet.gupta at linux dot dev" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/105666] New: RISC-V 507.cactuBSSN_r build has costly FMV instructions Date: Thu, 19 May 2022 22:33:33 +0000 [thread overview] Message-ID: <bug-105666-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105666 Bug ID: 105666 Summary: RISC-V 507.cactuBSSN_r build has costly FMV instructions Product: gcc Version: 12.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: vineet.gupta at linux dot dev Target Milestone: --- Created attachment 53001 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53001&action=edit Test case to generate FMV.d.x instructions SPEC2017 FP benchmark 507.cactu: ML_BSSN_Advect.cc:ML_BSSN_Advect_Body() has really ugly code causing high register pressure and ensuing spills of both FP and int register. Current riscv TARGET_REGISTER_MOVE_COST lacking any cost considerations, resorts to fp <--> int mov as opposed to spilling to stack. | fmv.d.x fa5,s9 # PDupwindNthSymm2Xt1, PDupwindNthSymm2Xt1 | .LVL325: | ld s9,184(sp) # _12469, %sfp | ... | .LVL339: | fmv.x.d s4,fa5 # PDupwindNthSymm2Xt1, PDupwindNthSymm2Xt1 The FMV.d.x / FMV.x.d instructions could be costly on certain micro-architectures and thus needs to be made tunable. Test case attached: ripped off of existing gcc/testsuite/gcc.c-torture/execute/pr28982a.c
next reply other threads:[~2022-05-19 22:33 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-05-19 22:33 vineet.gupta at linux dot dev [this message] 2022-05-19 22:45 ` [Bug target/105666] " vineet.gupta at linux dot dev 2022-05-19 22:51 ` pinskia at gcc dot gnu.org 2022-05-23 19:35 ` vineet.gupta at linux dot dev 2022-05-24 16:12 ` vineet.gupta at linux dot dev
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-105666-4@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).