[Bug optimization/14736] New: [tree-ssa] code quality regression

[Bug optimization/14736] New: [tree-ssa] code quality regression

[dann at godzilla dot ics dot uci dot edu]

There seems to be a code quality regression in tree-ssa between 
2004/03/08 and 2004/03/20 

The .vars dump for generate-3.4.ii from PR8361 generated by 
gcc version 3.5-tree-ssa 20040308 (merged 20040305)
has 100840 lines
the one generated by
gcc version 3.5-tree-ssa 20040320 (merged 20040307)
has 85811 lines.

Granted the number of lines in .vars is not the best measure of code
quality, but given the 15% size difference something seems wrong. 

Looking at the diff between the 2 I saw the following type of
difference in a few places:

 <L5>:;
-  if (__result == __first) goto <L6>; else goto <L7>;
+  se = (struct ELEMENT &)__first;
+  if (__result == (struct ELEMENT * const)se) goto <L6>; else goto <L7>; 


Given that this code is from std::vector::iterator it appears in quite a
few places. Look for example at:
typename std::vector<_Tp, _Alloc>::iterator std::vector<_Tp,
_Alloc>::erase(__gnu_cxx::__normal_iterator<_Tp*, std::vector<_Tp, _Alloc> >,
__gnu_cxx::__normal_iterator<_Tp*, std::vector<_Tp, _Alloc> >) [with _Tp =
STACK<int>::ELEMENT, _Alloc = std::allocator<STACK<int>::ELEMENT>] (this,
__first, __last)



Another oddity is code like:

<L38>:;
  __first = __first;
  __result = __result;

-- 
           Summary: [tree-ssa] code quality regression
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dann at godzilla dot ics dot uci dot edu
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-03-25 23:34 -------
Assigning to Diego.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |dnovillo at gcc dot gnu dot
                   |dot org                     |org
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-03-25 23:34:57
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-04-06 19:14 -------
I think this is better now but I might be looking into the wrong .vars the one with my cast 
pass included.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |compile-time-hog, memory-
                   |                            |hog, pessimizes-code
   Target Milestone|---                         |tree-ssa


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-16 01:25 -------
I think these regressions come from the movement away from convert to fold_convert in 
the middle-end.  I think I have a fix which also gets rid of most of the usefulness of my 
cast pass.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-17 00:01 -------
And no my patch did not fix this part but another some more work in fold_convert can 
help.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-02 04:32 -------
Mine caused by Dale's patch to use the language hooks.  I have a patch.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dnovillo at gcc dot gnu dot
                   |                            |org
         AssignedTo|dnovillo at gcc dot gnu dot |pinskia at gcc dot gnu dot
                   |org                         |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-02 04:33 -------
Here is the patch:
Index: tree-ssa.c
===============================================================
====
RCS file: /cvs/gcc/gcc/gcc/tree-ssa.c,v
retrieving revision 2.3
diff -u -p -r2.3 tree-ssa.c
--- tree-ssa.c	14 May 2004 02:29:23 -0000	2.3
+++ tree-ssa.c	2 Jun 2004 04:32:50 -0000
@@ -555,7 +555,8 @@ tree_ssa_useless_type_conversion_1 (tree
      so strip conversions that just switch between them.  */
   else if (POINTER_TYPE_P (inner_type)
            && POINTER_TYPE_P (outer_type)
-           && lang_hooks.types_compatible_p (inner_type, outer_type))
+           && lang_hooks.types_compatible_p (TREE_TYPE (inner_type),
+					     TREE_TYPE (outer_type)))
     return true;
 
   /* If both the inner and outer types are integral types, then the


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-02 04:41 -------
Much newer and simpler patch: <http://gcc.gnu.org/ml/gcc-patches/2004-06/msg00087.html>.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[dann at godzilla dot ics dot uci dot edu]

------- Additional Comments From dann at godzilla dot ics dot uci dot edu  2004-06-02 17:38 -------
(In reply to comment #7)
> Much newer and simpler patch:
<http://gcc.gnu.org/ml/gcc-patches/2004-06/msg00087.html>.

Great! Thanks for taking care of this!
Could you also post some before and after numbers? They should be very interesting. 
Like the number of lines in the dump files, or the number of temp variables
created. 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-06-02 18:56 -------
Subject: Bug 14736

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	pinskia@gcc.gnu.org	2004-06-02 18:56:54

Modified files:
	gcc            : ChangeLog tree-ssa.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/g++.dg/tree-ssa: ssa-cast-1.C ssa-sra-1.C 
	                               ssa-sra-2.C 

Log message:
	2004-06-02  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR tree-optimization/14736
	* g++.dg/tree-ssa/ssa-cast-1.C: New Test.
	
	PR tree-optimization/14042
	* g++.dg/tree-ssa/ssa-sra-1.C: New Test.
	
	PR tree-optimization/14729
	* g++.dg/tree-ssa/ssa-sra-2.C: New Test.
	
	2004-06-02  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR tree-optimization/14042
	PR tree-optimization/14729
	PR tree-optimization/14736
	* tree-ssa.c: Check the type which the pointer points to
	instead of the pointer types.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.3822&r2=2.3823
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-ssa.c.diff?cvsroot=gcc&r1=2.3&r2=2.4
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.3804&r2=1.3805
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/tree-ssa/ssa-cast-1.C.diff?cvsroot=gcc&r1=NONE&r2=1.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/tree-ssa/ssa-sra-1.C.diff?cvsroot=gcc&r1=NONE&r2=1.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/tree-ssa/ssa-sra-2.C.diff?cvsroot=gcc&r1=NONE&r2=1.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-02 19:00 -------
Dann, sorry I did not do any timings or any other numbers because I was to lazy to do any and I 
wantted to get this in and fixed.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736

[Bug tree-optimization/14736] [tree-ssa] code quality regression

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-02 19:58 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14736