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From: "neleai at seznam dot cz" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/67014] New: builtin_tolower is inefficient. Date: Sun, 26 Jul 2015 04:53:00 -0000 [thread overview] Message-ID: <bug-67014-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67014 Bug ID: 67014 Summary: builtin_tolower is inefficient. Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: neleai at seznam dot cz Target Milestone: --- Hi, When one uses __builtin_tolower it could be much slower to tolower. In this example builtin_tolower gets just expanded to call. If one uses tolower instead it gets expanded to getting table with __ctype_tolower_loc and then doing 1000 table lookups instead 1000 calls. #include <ctype.h> int foo(char *c) { int i; for(i=0;i<1000;i++) c[i]=__builtin_tolower(c[i]); }
next reply other threads:[~2015-07-26 4:53 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-07-26 4:53 neleai at seznam dot cz [this message] 2021-06-04 21:45 ` [Bug ipa/67014] " pinskia at gcc dot gnu.org 2021-06-10 15:17 ` marxin at gcc dot gnu.org 2021-08-18 12:40 ` marxin at gcc dot gnu.org
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