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* [Bug tree-optimization/56770] Partial sums loop optimization
[not found] <bug-56770-4@http.gcc.gnu.org/bugzilla/>
@ 2013-03-29 15:29 ` dje at gcc dot gnu.org
2013-03-29 15:55 ` Joost.VandeVondele at mat dot ethz.ch
` (3 subsequent siblings)
4 siblings, 0 replies; 5+ messages in thread
From: dje at gcc dot gnu.org @ 2013-03-29 15:29 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56770
David Edelsohn <dje at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2013-03-29
Ever Confirmed|0 |1
--- Comment #1 from David Edelsohn <dje at gcc dot gnu.org> 2013-03-29 15:29:38 UTC ---
Currently not implemented in GCC.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug tree-optimization/56770] Partial sums loop optimization
[not found] <bug-56770-4@http.gcc.gnu.org/bugzilla/>
2013-03-29 15:29 ` [Bug tree-optimization/56770] Partial sums loop optimization dje at gcc dot gnu.org
@ 2013-03-29 15:55 ` Joost.VandeVondele at mat dot ethz.ch
2013-03-29 18:12 ` dje at gcc dot gnu.org
` (2 subsequent siblings)
4 siblings, 0 replies; 5+ messages in thread
From: Joost.VandeVondele at mat dot ethz.ch @ 2013-03-29 15:55 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56770
Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |Joost.VandeVondele at mat
| |dot ethz.ch
--- Comment #2 from Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch> 2013-03-29 15:55:38 UTC ---
well actually related to PR25621, I think, and partially implemented via
-fvariable-expansion-in-unroller -ffast-math
would be nice to have this enabled (and well working) at -O3 or so.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug tree-optimization/56770] Partial sums loop optimization
[not found] <bug-56770-4@http.gcc.gnu.org/bugzilla/>
2013-03-29 15:29 ` [Bug tree-optimization/56770] Partial sums loop optimization dje at gcc dot gnu.org
2013-03-29 15:55 ` Joost.VandeVondele at mat dot ethz.ch
@ 2013-03-29 18:12 ` dje at gcc dot gnu.org
2013-03-29 19:38 ` [Bug middle-end/56770] " steven at gcc dot gnu.org
2013-03-29 19:53 ` dje at gcc dot gnu.org
4 siblings, 0 replies; 5+ messages in thread
From: dje at gcc dot gnu.org @ 2013-03-29 18:12 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56770
--- Comment #3 from David Edelsohn <dje at gcc dot gnu.org> 2013-03-29 18:11:54 UTC ---
I tried -funroll-loops -fvariable-expansion-in-unroller. I did not see any
additional benefit from -fvariable-expansion-in-unroller.
Unrolling helped somewhat, the intermediate sum was computed in each loop
iteration instead of sunk after the loop.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/56770] Partial sums loop optimization
[not found] <bug-56770-4@http.gcc.gnu.org/bugzilla/>
` (2 preceding siblings ...)
2013-03-29 18:12 ` dje at gcc dot gnu.org
@ 2013-03-29 19:38 ` steven at gcc dot gnu.org
2013-03-29 19:53 ` dje at gcc dot gnu.org
4 siblings, 0 replies; 5+ messages in thread
From: steven at gcc dot gnu.org @ 2013-03-29 19:38 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56770
Steven Bosscher <steven at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |missed-optimization
Status|NEW |ASSIGNED
Component|tree-optimization |middle-end
AssignedTo|unassigned at gcc dot |steven at gcc dot gnu.org
|gnu.org |
--- Comment #4 from Steven Bosscher <steven at gcc dot gnu.org> 2013-03-29 19:38:21 UTC ---
Interesting idea, I'll have a look.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/56770] Partial sums loop optimization
[not found] <bug-56770-4@http.gcc.gnu.org/bugzilla/>
` (3 preceding siblings ...)
2013-03-29 19:38 ` [Bug middle-end/56770] " steven at gcc dot gnu.org
@ 2013-03-29 19:53 ` dje at gcc dot gnu.org
4 siblings, 0 replies; 5+ messages in thread
From: dje at gcc dot gnu.org @ 2013-03-29 19:53 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56770
--- Comment #5 from David Edelsohn <dje at gcc dot gnu.org> 2013-03-29 19:53:44 UTC ---
Segher pointed out that the transformed code example is has a bug. The first
revised loop should test j+1 < NZ.
for (j = 0; j+1 < NZ; j += 2){
fValue += Q[j] / r[j];
fValue1 += Q[j+1] / r[j+1];
}
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2013-03-29 19:53 UTC | newest]
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[not found] <bug-56770-4@http.gcc.gnu.org/bugzilla/>
2013-03-29 15:29 ` [Bug tree-optimization/56770] Partial sums loop optimization dje at gcc dot gnu.org
2013-03-29 15:55 ` Joost.VandeVondele at mat dot ethz.ch
2013-03-29 18:12 ` dje at gcc dot gnu.org
2013-03-29 19:38 ` [Bug middle-end/56770] " steven at gcc dot gnu.org
2013-03-29 19:53 ` dje at gcc dot gnu.org
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