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* [Bug tree-optimization/100802] New: VRP fails to fold comparison with known value orders
@ 2021-05-27 14:56 fxue at os dot amperecomputing.com
2021-11-05 21:40 ` [Bug tree-optimization/100802] VRP fails to fold comparison using " amacleod at redhat dot com
2021-11-16 1:49 ` fxue at os dot amperecomputing.com
0 siblings, 2 replies; 3+ messages in thread
From: fxue at os dot amperecomputing.com @ 2021-05-27 14:56 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100802
Bug ID: 100802
Summary: VRP fails to fold comparison with known value orders
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: fxue at os dot amperecomputing.com
Target Milestone: ---
In the case below, it is obvious that we have value orders as i < a <= b inside
loop. So "if (i >= b)" could be optimized away, but VRP fails to do that.
int f1();
int f2();
int foo (unsigned a, unsigned b)
{
if (a <= b)
{
for (unsigned i = 0; i < a; i++)
{
f1 ();
if (i >= b)
f2 ();
}
}
return 0;
}
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-11-16 1:49 UTC | newest]
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2021-05-27 14:56 [Bug tree-optimization/100802] New: VRP fails to fold comparison with known value orders fxue at os dot amperecomputing.com
2021-11-05 21:40 ` [Bug tree-optimization/100802] VRP fails to fold comparison using " amacleod at redhat dot com
2021-11-16 1:49 ` fxue at os dot amperecomputing.com
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