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* [Bug optimization/15268] New: [tree-ssa] return statements are not combined on the tree level
@ 2004-05-03 17:19 pinskia at gcc dot gnu dot org
  2004-05-03 17:23 ` [Bug optimization/15268] " pinskia at gcc dot gnu dot org
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-05-03 17:19 UTC (permalink / raw)
  To: gcc-bugs

The following code (Derived from PR 15245) is not optimized to "return 0;" on the tree 
level.

char *f(char *x)
{
    char *ret = (char*)0;
    if( x > (char*)1 ) {
      if(x)
        return (char*)0;
    } 
    return ret;
}

-- 
           Summary: [tree-ssa] return statements are not combined on the
                    tree level
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Keywords: pessimizes-code, memory-hog, compile-time-hog, TREE
          Severity: enhancement
          Priority: P2
         Component: optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15268


^ permalink raw reply	[flat|nested] 6+ messages in thread
* [Bug optimization/15268] [tree-ssa] return statements are not combined on the tree level
  2004-05-03 17:19 [Bug optimization/15268] New: [tree-ssa] return statements are not combined on the tree level pinskia at gcc dot gnu dot org
@ 2004-05-03 17:23 ` pinskia at gcc dot gnu dot org
  2004-05-24 21:35 ` [Bug tree-optimization/15268] " pinskia at gcc dot gnu dot org
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-05-03 17:23 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-03 17:23 -------
Confirmed.  The reason why I put memory-hog and compile-time-hog is because the 
conversion from tree to RTL is costly and  also there are more basic blocks in rtl which is 
removed later on.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-05-03 17:23:33
               date|                            |
   Target Milestone|---                         |tree-ssa


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15268


^ permalink raw reply	[flat|nested] 6+ messages in thread
* [Bug tree-optimization/15268] [tree-ssa] return statements are not combined on the tree level
  2004-05-03 17:19 [Bug optimization/15268] New: [tree-ssa] return statements are not combined on the tree level pinskia at gcc dot gnu dot org
  2004-05-03 17:23 ` [Bug optimization/15268] " pinskia at gcc dot gnu dot org
@ 2004-05-24 21:35 ` pinskia at gcc dot gnu dot org
  2004-06-04 19:38 ` kazu at cs dot umass dot edu
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-05-24 21:35 UTC (permalink / raw)
  To: gcc-bugs



-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.5.0                       |---


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15268


^ permalink raw reply	[flat|nested] 6+ messages in thread
* [Bug tree-optimization/15268] [tree-ssa] return statements are not combined on the tree level
  2004-05-03 17:19 [Bug optimization/15268] New: [tree-ssa] return statements are not combined on the tree level pinskia at gcc dot gnu dot org
  2004-05-03 17:23 ` [Bug optimization/15268] " pinskia at gcc dot gnu dot org
  2004-05-24 21:35 ` [Bug tree-optimization/15268] " pinskia at gcc dot gnu dot org
@ 2004-06-04 19:38 ` kazu at cs dot umass dot edu
  2004-06-07 17:59 ` pinskia at gcc dot gnu dot org
  2004-07-09  7:10 ` pinskia at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: kazu at cs dot umass dot edu @ 2004-06-04 19:38 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From kazu at cs dot umass dot edu  2004-06-04 19:38 -------
The last tree-ssa form looks like so:

f (x)
{
  char * ret;

<bb 0>:
  if (x_2 > 1B) goto <L0>; else goto <L2>;

<L0>:;
  if (x_2 != 0B) goto <L1>; else goto <L2>;

<L1>:;
  return 0B;

<L2>:;
  return 0B;

}


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15268


^ permalink raw reply	[flat|nested] 6+ messages in thread
* [Bug tree-optimization/15268] [tree-ssa] return statements are not combined on the tree level
  2004-05-03 17:19 [Bug optimization/15268] New: [tree-ssa] return statements are not combined on the tree level pinskia at gcc dot gnu dot org
                   ` (2 preceding siblings ...)
  2004-06-04 19:38 ` kazu at cs dot umass dot edu
@ 2004-06-07 17:59 ` pinskia at gcc dot gnu dot org
  2004-07-09  7:10 ` pinskia at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-06-07 17:59 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-07 17:59 -------
Fixed by:
2004-06-07  Richard Henderson  <rth@redhat.com>

        * gimple-low.c (struct lower_data): Add the_return_label and
        one_return_stmt.
        (lower_function_body): Initialize and use them.
        (lower_return_expr): New.
        (lower_stmt): Call it.
        * gimplify.c (gimplify_return_expr): Force the argument to be either
        null or a result_decl.
        * tree-gimple.c: Update gimple grammer to match.
        * tree-ssa-copyrename.c (copy_rename_partition_coalesce): Deny
        coalescing of result_decls.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15268


^ permalink raw reply	[flat|nested] 6+ messages in thread
* [Bug tree-optimization/15268] [tree-ssa] return statements are not combined on the tree level
  2004-05-03 17:19 [Bug optimization/15268] New: [tree-ssa] return statements are not combined on the tree level pinskia at gcc dot gnu dot org
                   ` (3 preceding siblings ...)
  2004-06-07 17:59 ` pinskia at gcc dot gnu dot org
@ 2004-07-09  7:10 ` pinskia at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-07-09  7:10 UTC (permalink / raw)
  To: gcc-bugs



-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |3.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15268


^ permalink raw reply	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2004-07-09  7:10 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2004-05-03 17:19 [Bug optimization/15268] New: [tree-ssa] return statements are not combined on the tree level pinskia at gcc dot gnu dot org
2004-05-03 17:23 ` [Bug optimization/15268] " pinskia at gcc dot gnu dot org
2004-05-24 21:35 ` [Bug tree-optimization/15268] " pinskia at gcc dot gnu dot org
2004-06-04 19:38 ` kazu at cs dot umass dot edu
2004-06-07 17:59 ` pinskia at gcc dot gnu dot org
2004-07-09  7:10 ` pinskia at gcc dot gnu dot org

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