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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/98865] New: Missed transform of (a >> 63) * b Date: Thu, 28 Jan 2021 13:38:30 +0000 [thread overview] Message-ID: <bug-98865-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98865 Bug ID: 98865 Summary: Missed transform of (a >> 63) * b Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: rguenth at gcc dot gnu.org Target Milestone: --- unsigned long foo (unsigned long a, unsigned long b) { return (a >> 63) * b; } generates foo: .LFB0: .cfi_startproc shrq $63, %rdi movq %rdi, %rax imulq %rsi, %rax ret but we can do (like llvm): foo: # @foo .cfi_startproc # %bb.0: movq %rdi, %rax sarq $63, %rax andq %rsi, %rax retq
next reply other threads:[~2021-01-28 13:38 UTC|newest] Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-01-28 13:38 rguenth at gcc dot gnu.org [this message] 2021-01-28 13:40 ` [Bug middle-end/98865] " rguenth at gcc dot gnu.org 2021-01-28 14:26 ` jakub at gcc dot gnu.org 2021-03-07 2:46 ` pinskia at gcc dot gnu.org 2021-07-20 22:19 ` pinskia at gcc dot gnu.org 2021-09-22 18:19 ` cvs-commit at gcc dot gnu.org 2022-01-11 11:19 ` rguenth at gcc dot gnu.org 2022-05-18 15:24 ` cvs-commit at gcc dot gnu.org 2022-05-19 16:55 ` cvs-commit at gcc dot gnu.org 2022-05-27 8:02 ` cvs-commit at gcc dot gnu.org 2022-05-28 9:18 ` roger at nextmovesoftware dot com
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