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From: "xxs_chy at outlook dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/114797] New: Missed optimization : fail to merge memset with unrelated clobber Date: Sun, 21 Apr 2024 17:20:44 +0000 [thread overview] Message-ID: <bug-114797-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114797 Bug ID: 114797 Summary: Missed optimization : fail to merge memset with unrelated clobber Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: xxs_chy at outlook dot com Target Milestone: --- Godbolt link: https://godbolt.org/z/E581jvaPs Code like: ``` void src(char* config){ char stack[208]; memset(stack, 0, 184); *config = 0; memset(stack + 184, 0, 8); use(stack); } ``` can be transformed to ``` void tgt(char* config){ char stack[208]; memset(stack, 0, 192); *config = 0; use(stack); } ``` GCC doesn't merge them even both memsets overlap: https://godbolt.org/z/ffc6b8zqs
next reply other threads:[~2024-04-21 17:20 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-04-21 17:20 xxs_chy at outlook dot com [this message] 2024-04-21 19:26 ` [Bug tree-optimization/114797] " pinskia at gcc dot gnu.org 2024-04-21 19:55 ` xxs_chy at outlook dot com 2024-04-21 19:58 ` pinskia at gcc dot gnu.org
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