[Bug tree-optimization/39672] New: Local statics not promoted to const

[Bug tree-optimization/39672] New: Local statics not promoted to const

[rguenth at gcc dot gnu dot org]

For

int foo(void)
{
  static int blah = 1;
  return blah;
}

we should be able to promote blah to TREE_READONLY during ipa-reference (or
local analysis) if blah does not have its address taken and is not written
to in the function body.

This occurs for example in 189.lucas via

        real(kind=r16), save :: mt,one=1,two=2,one_fourth,pi,theta,theta2

note the save attribute.


-- 
           Summary: Local statics not promoted to const
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rguenth at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39672

[Bug tree-optimization/39672] Local statics not promoted to const

[hubicka at ucw dot cz]

------- Comment #1 from hubicka at ucw dot cz  2009-04-07 11:44 -------
Subject: Re:   New: Local statics not promoted to const

ipa-reference definitly is supposed to do this transform.  I will debug
why it does not in this testcase.

Honza


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39672

[Bug tree-optimization/39672] Local statics not promoted to const

[rguenther at suse dot de]

------- Comment #2 from rguenther at suse dot de  2009-04-07 12:14 -------
Subject: Re:  Local statics not promoted to
 const

On Tue, 7 Apr 2009, hubicka at ucw dot cz wrote:

> ------- Comment #1 from hubicka at ucw dot cz  2009-04-07 11:44 -------
> Subject: Re:   New: Local statics not promoted to const
> 
> ipa-reference definitly is supposed to do this transform.  I will debug
> why it does not in this testcase.

I think it only adjusts global statics.

Richard.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39672

[Bug tree-optimization/39672] Local statics not promoted to const

[hubicka at ucw dot cz]

------- Comment #3 from hubicka at ucw dot cz  2009-04-07 15:14 -------
Subject: Re:  Local statics not promoted to const

> I think it only adjusts global statics.
This is why I originally implemented varpool to have both local and
global static alike, so it should not.

Well, time to debug it ;)

Honza


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39672

[Bug tree-optimization/39672] Local statics not promoted to const

[rguenth at gcc dot gnu dot org]

------- Comment #4 from rguenth at gcc dot gnu dot org  2009-04-08 10:21 -------
Err, this works.  I just messed up my local tree.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WORKSFORME


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39672