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* [Bug tree-optimization/27800] New: extra temprorary created when gimplifying return
@ 2006-05-29 18:20 dann at godzilla dot ics dot uci dot edu
2006-05-29 20:52 ` [Bug tree-optimization/27800] " dann at godzilla dot ics dot uci dot edu
2006-05-29 21:14 ` pinskia at gcc dot gnu dot org
0 siblings, 2 replies; 3+ messages in thread
From: dann at godzilla dot ics dot uci dot edu @ 2006-05-29 18:20 UTC (permalink / raw)
To: gcc-bugs
One would think that the temporaries created when gimplifying the following
2 functions would be the same:
void hhh (int a, int b, int c){ bar (a?b:c); }
int iii (int a, int b, int c){ return (a?b:c); }
But they are not:
hhh (a, b, c)
{
int iftmp.0;
if (a != 0)
{
iftmp.0 = b;
}
else
{
iftmp.0 = c;
}
bar (iftmp.0);
}
This one is fine.
But this one:
iii (a, b, c)
{
int D.2128;
int iftmp.1;
if (a != 0)
{
iftmp.1 = b;
}
else
{
iftmp.1 = c;
}
D.2128 = iftmp.1;
return D.2128;
}
creates an extra temporary for the return expression. It would be more memory
efficient if it would just use "iftmp.1" as the first function does.
--
Summary: extra temprorary created when gimplifying return
Product: gcc
Version: 4.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: dann at godzilla dot ics dot uci dot edu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27800
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug tree-optimization/27800] extra temprorary created when gimplifying return
2006-05-29 18:20 [Bug tree-optimization/27800] New: extra temprorary created when gimplifying return dann at godzilla dot ics dot uci dot edu
@ 2006-05-29 20:52 ` dann at godzilla dot ics dot uci dot edu
2006-05-29 21:14 ` pinskia at gcc dot gnu dot org
1 sibling, 0 replies; 3+ messages in thread
From: dann at godzilla dot ics dot uci dot edu @ 2006-05-29 20:52 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from dann at godzilla dot ics dot uci dot edu 2006-05-29 20:51 -------
An even simpler example which occurs quite frequently in programs:
int jjj (int a){ return bar (a); }
jjj (a)
{
int D.1891;
int D.1892;
D.1892 = bar (a);
D.1891 = D.1892;
return D.1891;
}
--
dann at godzilla dot ics dot uci dot edu changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|extra temprorary created |extra temprorary created
|when gimplifying return |when gimplifying return
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27800
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug tree-optimization/27800] extra temprorary created when gimplifying return
2006-05-29 18:20 [Bug tree-optimization/27800] New: extra temprorary created when gimplifying return dann at godzilla dot ics dot uci dot edu
2006-05-29 20:52 ` [Bug tree-optimization/27800] " dann at godzilla dot ics dot uci dot edu
@ 2006-05-29 21:14 ` pinskia at gcc dot gnu dot org
1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-05-29 21:14 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from pinskia at gcc dot gnu dot org 2006-05-29 21:13 -------
Confirmed.
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2006-05-29 21:13:57
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27800
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2006-05-29 21:14 UTC | newest]
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2006-05-29 18:20 [Bug tree-optimization/27800] New: extra temprorary created when gimplifying return dann at godzilla dot ics dot uci dot edu
2006-05-29 20:52 ` [Bug tree-optimization/27800] " dann at godzilla dot ics dot uci dot edu
2006-05-29 21:14 ` pinskia at gcc dot gnu dot org
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