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From: "rguenth at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/28685] Multiple comparisons are not simplified Date: Sun, 12 Oct 2008 20:46:00 -0000 [thread overview] Message-ID: <20081012204538.9542.qmail@sourceware.org> (raw) In-Reply-To: <bug-28685-1649@http.gcc.gnu.org/bugzilla/> ------- Comment #4 from rguenth at gcc dot gnu dot org 2008-10-12 20:45 ------- Another similar, but yet different case: int test(int a, int b) { int lt = a < b; int eq = a == b; if (lt) return 1; return eq; } this is what we "optimize" it to: test (int a, int b) { int eq; <bb 2>: eq_5 = a_2(D) == b_3(D); if (a_2(D) < b_3(D)) goto <bb 4>; else goto <bb 3>; <bb 3>: <bb 4>: # eq_1 = PHI <1(2), eq_5(3)> return eq_1; test: pushl %ebp movl $1, %eax movl %esp, %ebp movl 12(%ebp), %edx cmpl %edx, 8(%ebp) jl .L3 sete %al movzbl %al, %eax .L3: popl %ebp ret -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28685
next prev parent reply other threads:[~2008-10-12 20:46 UTC|newest] Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top 2006-08-10 18:15 [Bug middle-end/28685] New: " uros at kss-loka dot si 2006-08-10 18:18 ` [Bug middle-end/28685] " pinskia at gcc dot gnu dot org 2008-04-30 15:13 ` rguenth at gcc dot gnu dot org 2008-09-06 16:34 ` ubizjak at gmail dot com 2008-10-12 20:46 ` rguenth at gcc dot gnu dot org [this message] 2009-04-24 9:24 ` rguenth at gcc dot gnu dot org 2009-04-24 9:25 ` rguenth at gcc dot gnu dot org 2009-06-24 7:49 ` steven at gcc dot gnu dot org 2009-06-24 9:15 ` rguenth at gcc dot gnu dot org 2009-09-17 10:25 ` ubizjak at gmail dot com 2010-05-07 2:32 ` sandra at codesourcery dot com 2010-05-08 3:44 ` sandra at codesourcery dot com 2010-05-08 15:54 ` sandra at gcc dot gnu dot org 2010-05-24 13:22 ` sandra at codesourcery dot com 2010-05-25 8:12 ` rguenther at suse dot de 2010-06-01 2:24 ` sandra at codesourcery dot com 2010-06-08 18:16 ` sandra at gcc dot gnu dot org [not found] <bug-28685-4@http.gcc.gnu.org/bugzilla/> 2012-01-12 1:07 ` pinskia at gcc dot gnu.org 2012-02-05 12:42 ` ubizjak at gmail dot com 2012-02-06 21:37 ` ubizjak at gmail dot com 2012-04-22 12:42 ` ubizjak at gmail dot com 2012-04-22 12:46 ` ubizjak at gmail dot com 2012-04-22 12:48 ` ubizjak at gmail dot com 2014-10-31 4:02 ` pinskia at gcc dot gnu.org
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