[Bug tree-optimization/30104] missed code motion optimization (invariant control structures)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=30104

Andrew Pinski  changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 Resolution|--- |FIXED
   Target Milestone|--- |5.0

--- Comment #6 from Andrew Pinski  ---
Been fixed since at least 5.0.  Might have been fixed earlier.

Note the code is not exactly the same on aarch64-linux-gnu but the inner loops
are.

[Bug tree-optimization/30104] missed code motion optimization (invariant control structures)

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30104

Andrew Pinski pinskia at gcc dot gnu.org changed:

   What|Removed |Added

   Keywords||TREE
   Last reconfirmed|2006-12-07 14:17:34 |2012-02-08

--- Comment #5 from Andrew Pinski pinskia at gcc dot gnu.org 2012-02-08 
23:17:57 UTC ---
On MIPS64-linux-gnu, the code is the same in the assembly but we don't do this
at the tree level yet.

[Bug tree-optimization/30104] missed code motion optimization (invariant control structures)

[rguenth at gcc dot gnu dot org]

--- Comment #1 from rguenth at gcc dot gnu dot org  2006-12-07 14:17 ---
Confirmed.


-- 

rguenth at gcc dot gnu dot org changed:

   What|Removed |Added

 CC||rguenth at gcc dot gnu dot
   ||org
   Severity|normal  |enhancement
 Status|UNCONFIRMED |NEW
 Ever Confirmed|0   |1
   Keywords||missed-optimization
   Last reconfirmed|-00-00 00:00:00 |2006-12-07 14:17:34
   date||


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30104

[Bug tree-optimization/30104] missed code motion optimization (invariant control structures)

[pinskia at gcc dot gnu dot org]

--- Comment #2 from pinskia at gcc dot gnu dot org  2006-12-07 16:46 ---
isn't this the same as loop  unswitching?
PS This was done from a PS3! 


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30104

[Bug tree-optimization/30104] missed code motion optimization (invariant control structures)

[rguenth at gcc dot gnu dot org]

--- Comment #3 from rguenth at gcc dot gnu dot org  2006-12-07 16:49 ---
unswitching would duplicate the whole loop here, so not exactly I think.  But
if-conversion to

  j = COND_EXPR p, 1, 2

or

  j = 2 - (int)p;

would make j loop invariant.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30104

[Bug tree-optimization/30104] missed code motion optimization (invariant control structures)

[dann at godzilla dot ics dot uci dot edu]

--- Comment #4 from dann at godzilla dot ics dot uci dot edu  2006-12-07 
18:24 ---
(In reply to comment #3)
 unswitching would duplicate the whole loop here, so not exactly I think.  But
 if-conversion to
 
   j = COND_EXPR p, 1, 2
 
 or
 
   j = 2 - (int)p;
 
 would make j loop invariant.

if-conversion would solve this particular testcase, but the more general case
of moving invariant control structures out of the loop is probably more
interesting. 


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30104