[Bug tree-optimization/23821] [4.0/4.1 Regression] DOM and VRP creating harder to optimize code

2005-11-14 Thread rakdver at gcc dot gnu dot org 


--- Comment #5 from rakdver at gcc dot gnu dot org  2005-11-14 09:16 ---
The testcase comes from gcc testsuite.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23821

[Bug tree-optimization/23821] [4.0/4.1 Regression] DOM and VRP creating harder to optimize code

2005-11-13 Thread steven at gcc dot gnu dot org 


--- Comment #4 from steven at gcc dot gnu dot org  2005-11-13 16:17 ---
What happens here is just copy propagation by DOM and VRP for conditional
copies, e.g. with if (a==b) ... we can record b as a copy of a, or a as a
copy of b.  In this case, copy propagation just happens to make IV analysis
hard (or impossible).

Now, this sounds bad.  But does this code really happen often enough in real
world code to justify spending hours on figuring out how to fix this?

Zdenek, where does your example come from?


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23821

[Bug tree-optimization/23821] [4.0/4.1 Regression] DOM and VRP creating harder to optimize code

2005-10-30 Thread mmitchel at gcc dot gnu dot org 


--- Comment #3 from mmitchel at gcc dot gnu dot org  2005-10-31 05:42 
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Leaving as P2, pending investigation.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23821

[Bug tree-optimization/23821] [4.0/4.1 Regression] DOM and VRP creating harder to optimize code

2005-10-16 Thread pinskia at gcc dot gnu dot org 


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pinskia at gcc dot gnu dot org changed:

   What|Removed |Added

 CC||pinskia at gcc dot gnu dot
   ||org
   Severity|normal  |minor


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23821

[Bug tree-optimization/23821] [4.0/4.1 Regression] DOM and VRP creating harder to optimize code

2005-09-27 Thread mmitchel at gcc dot gnu dot org 


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   What|Removed |Added

   Target Milestone|4.0.2   |4.0.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23821

[Bug tree-optimization/23821] [4.0/4.1 Regression] DOM and VRP creating harder to optimize code

2005-09-11 Thread pinskia at gcc dot gnu dot org 

--- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-11 
15:19 ---
It is not just DOM on the mainline, it is also VRP

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   What|Removed |Added

Summary|[4.0/4.1 Regression] Dom|[4.0/4.1 Regression] DOM and
   |creating harder to optimize |VRP creating harder to
   |code|optimize code


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23821