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From: "f.boesing at gmx dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/67242] New: Missing optimization with float
Date: Sun, 16 Aug 2015 20:12:00 -0000 [thread overview]
Message-ID: <bug-67242-4@http.gcc.gnu.org/bugzilla/> (raw)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67242
Bug ID: 67242
Summary: Missing optimization with float
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: f.boesing at gmx dot de
Target Milestone: ---
testcase:
int n, dummy;
float dummyfloat;
void bug(void)
{
for(n=0; n<1000; n++)
dummy = n;
for(n=0; n<1000; n++)
dummyfloat = n;
}
the first loop (dummy=) is optimized away with -O2 and -O3
the second (dummyfloat=) NOT.
Tested with 4.9.2 & 4.9.3, targets x86-64, arm-thumb and arm.
commandline: gcc -O2 bug.c -S
next reply other threads:[~2015-08-16 20:12 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-16 20:12 f.boesing at gmx dot de [this message]
2015-08-16 20:14 ` [Bug c/67242] " f.boesing at gmx dot de
2015-08-16 20:28 ` f.boesing at gmx dot de
2015-08-17 7:24 ` [Bug tree-optimization/67242] Missing optimization with float IV in SCEV-CCP rguenth at gcc dot gnu.org
2021-12-15 21:56 ` pinskia at gcc dot gnu.org
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