[Bug tree-optimization/15991] New: phi nodes with identical arguments still remain at t50.tailc

[Bug tree-optimization/15991] New: phi nodes with identical arguments still remain at t50.tailc

[kazu at cs dot umass dot edu]

# grep "PHI <0B([0-9]*), 0B([0-9]*)>" *.i.t50*
bb-reorder.i.t50.tailc:  # best_edge.1682_439 = PHI <0B(64), 0B(85)>;
cfgrtl.i.t50.tailc:  # x_36 = PHI <0B(4), 0B(8)>;
expmed.i.t50.tailc:  # tem_214 = PHI <0B(84), 0B(85)>;
optabs.i.t50.tailc:  # temp_393 = PHI <0B(30), 0B(29)>;
optabs.i.t50.tailc:  # temp_106 = PHI <0B(92), 0B(91)>;
recog.i.t50.tailc:  # eh_edge_50 = PHI <0B(34), 0B(31)>;
recog.i.t50.tailc:  # out_set_5 = PHI <0B(6), 0B(8)>;
tree-ssa-ccp.i.t50.tailc:  # uses_4 = PHI <0B(5), 0B(6)>;
tree-ssa-forwprop.i.t50.tailc:  # df_786 = PHI <0B(8), 0B(9)>;

I have yet to find a small testcase for the above.
It may be just a matter of running redphi one more time.

-- 
           Summary: phi nodes with identical arguments still remain at
                    t50.tailc
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: kazu at cs dot umass dot edu
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991

[Bug tree-optimization/15991] phi nodes with identical arguments still remain at t50.tailc

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-15 02:51 -------
Confirmed, this seems very important as we are missing a lot of constant propagation.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-06-15 02:51:32
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991

[Bug tree-optimization/15991] phi nodes with identical arguments still remain at t50.tailc

[rakdver at gcc dot gnu dot org]

------- Additional Comments From rakdver at gcc dot gnu dot org  2004-06-15 16:11 -------
kill_redundant_phi_nodes does not handle these cases since the variables are 
pointers, and copy propagating constants for pointers requires folding the 
statements and rewriting the ssa form afterwards, which I originally wanted to 
avoid.  Now that we from some reason need to rewrite the ssa form anyway, it 
should be fairly easy to implement.

I however do not know why dom+dce fail to eliminate this.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991

[Bug tree-optimization/15991] phi nodes with identical arguments still remain at t50.tailc

[rakdver at gcc dot gnu dot org]

------- Additional Comments From rakdver at gcc dot gnu dot org  2004-06-17 14:52 -------
Patch:

http://gcc.gnu.org/ml/gcc-patches/2004-06/msg01402.html

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991

[Bug tree-optimization/15991] phi nodes with identical arguments still remain at t50.tailc

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-06-17 17:47 -------
Subject: Bug 15991

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	rakdver@gcc.gnu.org	2004-06-17 17:47:47

Modified files:
	gcc            : ChangeLog tree-cfg.c tree-flow-inline.h 
	                 tree-flow.h tree-ssa.c tree-ssanames.c tree.h 

Log message:
	PR tree-optimization/15991
	* tree-cfg.c (tree_block_label): Export.
	* tree-flow-inline.h (bsi_after_labels): New function.
	* tree-flow.h (bsi_after_labels, tree_block_label): Declare.
	* tree-ssa.c (propagate_into_addr): New function.
	(replace_immediate_uses): Handle propagation of pointer constants.
	(raise_value): Do not restrict propagation of pointer constants.
	* tree-ssanames.c (duplicate_ssa_name): New function.
	* tree.h (duplicate_ssa_name): Declare.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.4016&r2=2.4017
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-cfg.c.diff?cvsroot=gcc&r1=2.12&r2=2.13
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-flow-inline.h.diff?cvsroot=gcc&r1=2.8&r2=2.9
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-flow.h.diff?cvsroot=gcc&r1=2.8&r2=2.9
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-ssa.c.diff?cvsroot=gcc&r1=2.9&r2=2.10
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-ssanames.c.diff?cvsroot=gcc&r1=2.2&r2=2.3
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree.h.diff?cvsroot=gcc&r1=1.519&r2=1.520



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991

[Bug tree-optimization/15991] phi nodes with identical arguments still remain at t50.tailc

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-17 17:53 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991

[Bug tree-optimization/15991] phi nodes with identical arguments still remain at t50.tailc

[dnovillo at redhat dot com]

------- Additional Comments From dnovillo at redhat dot com  2004-06-17 17:59 -------
Subject: Re:  phi nodes with identical
	arguments still remain at t50.tailc

On Thu, 2004-06-17 at 13:47, cvs-commit at gcc dot gnu dot org wrote:

> 	PR tree-optimization/15991
> 	* tree-cfg.c (tree_block_label): Export.
> 	* tree-flow-inline.h (bsi_after_labels): New function.
> 	* tree-flow.h (bsi_after_labels, tree_block_label): Declare.
> 	* tree-ssa.c (propagate_into_addr): New function.
> 	(replace_immediate_uses): Handle propagation of pointer constants.
> 	(raise_value): Do not restrict propagation of pointer constants.
> 	* tree-ssanames.c (duplicate_ssa_name): New function.
> 	* tree.h (duplicate_ssa_name): Declare.
> 
Did you also add a test case?  Or was there one present already?


Thanks.  Diego.



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991

[Bug tree-optimization/15991] phi nodes with identical arguments still remain at t50.tailc

[pinskia at gcc dot gnu dot org]

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15991