[Bug tree-optimization/18048] [4.0 Regression] mgrid loop performance regression with ivopts (register pressure)

[dje at gcc dot gnu dot org]

--- Additional Comments From dje at gcc dot gnu dot org  2005-02-14 16:03 
---
With -O2/-O3 -funroll loops -fswitch-loops -fpeel-loops, mgrid (and swim) no 
longer regress.  With just -O2/-O3, performance regression for mgrid remains 
(and swim performance dropped dramatically).

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18048

[Bug tree-optimization/18048] [4.0 Regression] mgrid loop performance regression with ivopts (register pressure)

[pinskia at gcc dot gnu dot org]

--- Additional Comments From pinskia at gcc dot gnu dot org  2005-02-14 
15:52 ---
(In reply to comment #15)
> Is this fixed now? 
No, it regressed again.
See .

-- 
   What|Removed |Added

 Status|WAITING |NEW
   Last reconfirmed|2004-10-22 17:35:50 |2005-02-14 15:52:02
   date||


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18048

[Bug tree-optimization/18048] [4.0 Regression] mgrid loop performance regression with ivopts (register pressure)

[steven at gcc dot gnu dot org]

--- Additional Comments From steven at gcc dot gnu dot org  2005-02-14 
10:22 ---
Is this fixed now? 

-- 
   What|Removed |Added

 Status|NEW |WAITING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18048

[Bug tree-optimization/18048] [4.0 Regression] mgrid loop performance regression with ivopts (register pressure)

[pinskia at gcc dot gnu dot org]

--- Additional Comments From pinskia at gcc dot gnu dot org  2005-02-10 
21:15 ---
I looked at the code generation after Zdenek's patch for PR 19701 and it looks 
much better but I don't 
have a machine to test SPEC on.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18048

[Bug tree-optimization/18048] [4.0 Regression] mgrid loop performance regression with ivopts (register pressure)

[pinskia at gcc dot gnu dot org]

-- 
Bug 18048 depends on bug 19701, which changed state.

Bug 19701 Summary: [4.0 regression] Way too many IVs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19701

   What|Old Value   |New Value

 Status|NEW |RESOLVED
 Resolution||FIXED

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18048

[Bug tree-optimization/18048] [4.0 Regression] mgrid loop performance regression with ivopts (register pressure)

[pinskia at gcc dot gnu dot org]

--- Additional Comments From pinskia at gcc dot gnu dot org  2005-01-30 
04:36 ---
PR 19701 is an example of where ivopts causes a regression in that we create 
too many IVs.

-- 
   What|Removed |Added

  BugsThisDependsOn||19701


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18048