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From: "acoplan at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/103633] New: Missed popcount recognition Date: Thu, 09 Dec 2021 15:29:59 +0000 [thread overview] Message-ID: <bug-103633-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103633 Bug ID: 103633 Summary: Missed popcount recognition Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: acoplan at gcc dot gnu.org Target Milestone: --- For: int f1 (unsigned long b) { int c = 0; while (b) { b &= b - 1; c++; } return c; } int f2(unsigned long x) { int c = 0; for (; x; x >>= 1) { if (x & 1) c++; } return c; } GCC recognizes f1 as popcount but not the more naive f2.
next reply other threads:[~2021-12-09 15:29 UTC|newest] Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-12-09 15:29 acoplan at gcc dot gnu.org [this message] 2021-12-09 15:42 ` [Bug tree-optimization/103633] " pinskia at gcc dot gnu.org 2022-10-10 18:10 ` pinskia at gcc dot gnu.org
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