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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/114169] miss optimization of repeat load&store in place Date: Thu, 07 Mar 2024 08:46:16 +0000 [thread overview] Message-ID: <bug-114169-4-aPIF7hRiwx@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-114169-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114169 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Severity|normal |enhancement Status|UNCONFIRMED |NEW Last reconfirmed| |2024-03-07 Ever confirmed|0 |1 Component|rtl-optimization |middle-end --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Confirmed. Reduced testcase: ``` struct S0 { int f0; int t[3+4]; }; struct S0 g_2; struct S0 g_4; void func_1() { //struct S0 b = g_2; g_4 = g_2; struct S0 b = g_4; g_4.f0 = 0; g_2 = b; } void func_2() { struct S0 b = g_2; g_4 = b; g_4.f0 = 0; g_2 = b; } ``` We still get an extra load/store with func_2 but it least it is not a dependent load/store ... Basically GCC doesn't notice that g_2 = b = g_2 was a no-op.
prev parent reply other threads:[~2024-03-07 8:46 UTC|newest] Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-02-29 15:35 [Bug rtl-optimization/114169] New: " absoler at smail dot nju.edu.cn 2024-03-07 8:46 ` pinskia at gcc dot gnu.org [this message]
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