[Bug optimization/14109] New: Can not compile correctly with -O1 option on IA64.

[Bug optimization/14109] New: Can not compile correctly with -O1 option on IA64.

[wf_cs at yahoo dot com]

On ia64 with -O1 the compiler runs into dead cycle compiling this C code:

void
fft (double fxr[], int m)
{
  int l;
  int le;
  double u1 = 1.0;
  double w1;

  l = 1;
  while (1)
    {
      if (l > m)
        break; 
      {
        int count_12;
        int vaI_11;

        le = 1;
        vaI_11 = 2;
        count_12 = l;
        while (1)
          {
            if ((count_12 & 1) == 1)
              {
                le = le * vaI_11;
              }
            count_12 = count_12 / 2;
            if (count_12 == 0)
	      break;
            vaI_11 = vaI_11 * vaI_11;
          }
      }
      u1 = 1.0;
      w1 = cos (3.1415926 / 0.5);
      {
        int count_14;
        count_14 = le;
        while (1)
          {
            if (count_14 <= 0)
	      break;
            {
              int count_16;
              count_16 = le;
              while (1)
                {
                  if (count_16 <= 0)
		    break;
                  fxr[count_16] = fxr[count_16] + u1;
                  count_16 = count_16 - 1;
                }
            }
            u1 = u1 * w1;
            count_14 = count_14 - 1;
          }
      }
      l = l + 1;
    }
}

-- 
           Summary: Can not compile correctly with -O1 option on IA64.
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: wf_cs at yahoo dot com
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109

[Bug optimization/14109] Can not compile correctly with -O1 option on IA64.

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-02-11 16:29 -------
dnovillo confirmed this and said it was in life analysis.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code, RTL


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109

[Bug optimization/14109] Can not compile correctly with -O1 option on IA64.

[wf_cs at yahoo dot com]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   GCC host triplet|                            |ia64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109

[Bug optimization/14109] [tree-ssa]Can not compile correctly with -O1 option on IA64.

[wf_cs at yahoo dot com]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Can not compile correctly   |[tree-ssa]Can not compile
                   |with -O1 option on IA64.    |correctly with -O1 option on
                   |                            |IA64.


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109

[Bug optimization/14109] [tree-ssa]Can not compile correctly with -O1 option on IA64.

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-02-12 01:00 -------
Had ment to confirm this.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-02-12 01:00:44
               date|                            |
   Target Milestone|---                         |tree-ssa


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109

[Bug optimization/14109] [tree-ssa]Can not compile correctly with -O1 option on IA64.

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2004-03-29 22:56 -------
I cannot reproduce this: 
 
$ ../cc1 t.c --version 
GNU C version 3.5-tree-ssa 20040329 (merged 20040324) (ia64-unknown-linux-gnu) 
        compiled by GNU C version 3.5-tree-ssa 20040329 (merged 20040324). 
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096 
$ ../cc1 t.c -O 
 fft 
 
Execution times (seconds) 
 TOTAL                 :   0.03             0.01             0.04 
Extra diagnostic checks enabled; compiler may run slowly. 
Configure with --disable-checking to disable checks. 
$ ../cc1 t.c -O2 
 fft 
 
Analyzing compilation unit 
Performing intraprocedural optimizations 
Assembling functions: 
 fft 
 
Execution times (seconds) 
 parser                :   0.01 (12%) usr   0.00 ( 0%) sys   0.00 ( 6%) wall 
 TOTAL                 :   0.05             0.00             0.05 
Extra diagnostic checks enabled; compiler may run slowly. 
Configure with --disable-checking to disable checks. 
$ ../cc1 t.c 
 fft 
 
Execution times (seconds) 
 TOTAL                 :   0.03             0.00             0.03 
Extra diagnostic checks enabled; compiler may run slowly. 
Configure with --disable-checking to disable checks. 
 
Feng, do you still see this bug? 

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |WAITING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109

[Bug optimization/14109] [tree-ssa]Can not compile correctly with -O1 option on IA64.

[wf_cs at yahoo dot com]

------- Additional Comments From wf_cs at yahoo dot com  2004-03-31 09:26 -------
No, I cannot see the bug. But I am not sure it will not jump out any longer. I 
found this bug when I tried to optimize the fortran power operator (**). If 
this bug can be sure to be fixed, I will give the patch optimizing power in 
fortran.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109

[Bug optimization/14109] [tree-ssa]Can not compile correctly with -O1 option on IA64.

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-03-31 12:47 -------
Cannot be reproduced any more, if you see it again, please file a new bug.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14109