[Bug optimization/14187] New: [tree-ssa] restricted pointers should not alias

[Bug optimization/14187] New: [tree-ssa] restricted pointers should not alias

[dann at godzilla dot ics dot uci dot edu]

Given:
extern void link_error (void);

void bar0 (int * __restrict__ arr1, int * __restrict__ arr2)
{
  arr1[0] = 1;
  arr2[0] = 1;
  if (arr1[0] != 1)
    link_error ();
}

arr1 and arr2 should not alias, hence the "if" should be eliminated

The .optimized dump is: 

bar0 (arr1, arr2)
{
<bb 0>:
  #   TMT.46_5 = VDEF <TMT.46_4>;
  *arr1 = 1;
  #   TMT.46_6 = VDEF <TMT.46_5>;
  *arr2 = 1;
  if (*arr1 != 1) goto <L0>; else goto <L1>;

<L0>:;
  #   TMT.46_7 = VDEF <TMT.46_6>;
  link_error ();

<L1>:;
  return;

}

-- 
           Summary: [tree-ssa] restricted pointers should not alias
           Product: gcc
           Version: unknown
            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=14187

[Bug optimization/14187] [tree-ssa] restricted pointers should not alias

[falk at debian dot org]

------- Additional Comments From falk at debian dot org  2004-02-18 11:04 -------
Works for me with GNU C version 3.5-tree-ssa 20040217 (merged
20040211) (alphaev68-unknown-linux-gnu):

0000000000000000 <bar0>:
   0:   01 00 3f 20     lda     t0,1
   4:   00 00 31 b0     stl     t0,0(a1)
   8:   00 00 30 b0     stl     t0,0(a0)
   c:   01 80 fa 6b     ret

Which version and target are you seeing this problem for?

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14187

[Bug optimization/14187] [tree-ssa] restricted pointers should not alias on the tree level

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-02-18 13:06 -------
Confirmed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |enhancement
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
           Keywords|                            |pessimizes-code
   Last reconfirmed|0000-00-00 00:00:00         |2004-02-18 13:06:02
               date|                            |
            Summary|[tree-ssa] restricted       |[tree-ssa] restricted
                   |pointers should not alias   |pointers should not alias on
                   |                            |the tree level
   Target Milestone|---                         |tree-ssa
            Version|unknown                     |tree-ssa


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14187

[Bug optimization/14187] [tree-ssa] restricted pointers should not alias on the tree level

[dnovillo at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |dnovillo at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14187

[Bug optimization/14187] [tree-ssa] restricted pointers should not alias on the tree level

[dann at godzilla dot ics dot uci dot edu]

------- Additional Comments From dann at godzilla dot ics dot uci dot edu  2004-03-12 17:15 -------
Interestingly the following code is optimized:

#include <stdlib.h>

extern int foo (int * , int *);
void bar1 (void)
{
  int * arr1 = malloc (12);
  int * arr2 = malloc (12);
  arr1[0] = 1;
  arr2[0] = 1;
  if (arr1[0] != 1)
    link_error ();
  foo (arr1, arr2);
}


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14187

[Bug tree-optimization/14187] [tree-ssa] restricted pointers should not alias on the tree level

[pinskia at gcc dot gnu dot org]

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14187

[Bug tree-optimization/14187] [tree-ssa] restricted pointers should not alias on the tree level

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-07-02 00:19 -------
Patch here: <http://gcc.gnu.org/ml/gcc-patches/2004-07/msg00116.html>.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14187