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From: "rsandifo at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/95341] New: Poor vector_size decomposition when SVE is enabled Date: Tue, 26 May 2020 16:44:05 +0000 [thread overview] Message-ID: <bug-95341-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95341 Bug ID: 95341 Summary: Poor vector_size decomposition when SVE is enabled Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: rsandifo at gcc dot gnu.org Target Milestone: --- Target: aarch64*-*-* Compiling the following with -O2 -march=armv8-a: typedef unsigned int uint_vec __attribute__((vector_size(32))); uint_vec f1(uint_vec x, uint_vec y) { return x + y; } generates nice Advanced SIMD code: ld1 {v4.16b - v5.16b}, [x0] ld1 {v2.16b - v3.16b}, [x1] add v0.4s, v4.4s, v2.4s add v1.4s, v5.4s, v3.4s st1 {v0.16b - v1.16b}, [x8] ret But compiling with -march=armv8.2-a+sve generates extremely bad scalar code, so bad that I'll spare people's eyes by not quoting it here. I haven't yet analysed this or checked whether it's a regression.
next reply other threads:[~2020-05-26 16:44 UTC|newest] Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-05-26 16:44 rsandifo at gcc dot gnu.org [this message] 2020-05-26 16:55 ` [Bug target/95341] " ktkachov at gcc dot gnu.org 2020-05-26 17:13 ` ktkachov at gcc dot gnu.org 2020-05-26 17:21 ` rsandifo at gcc dot gnu.org 2020-05-27 7:38 ` rguenth at gcc dot gnu.org 2024-02-27 8:08 ` pinskia at gcc dot gnu.org
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