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From: "bonzini at gnu dot org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/26190] New: combine misses some distributivity Date: Thu, 09 Feb 2006 09:06:00 -0000 [thread overview] Message-ID: <bug-26190-7849@http.gcc.gnu.org/bugzilla/> (raw) In this code, unsigned short crc (unsigned short crc, unsigned char data) { unsigned char i, x16; for (i = 0; i < 8; i++) { x16 = (data ^ (unsigned char) crc) & 1; data >>= 1; if (x16) { crc ^= 0x4002; crc >>= 1; crc |= 0x8000; } else crc >>= 1; } return crc; } the `then' branch of the if-statement should become crc >>= 1; crc ^= 0xA001; Seems related to bug 16798. Paolo -- Summary: combine misses some distributivity Product: gcc Version: 4.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: rtl-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: bonzini at gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26190
next reply other threads:[~2006-02-09 9:06 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2006-02-09 9:06 bonzini at gnu dot org [this message] 2006-02-09 9:07 ` [Bug rtl-optimization/26190] " bonzini at gnu dot org 2006-02-09 13:31 ` pinskia at gcc dot gnu dot org 2006-02-25 19:49 ` pinskia at gcc dot gnu dot org
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