[Bug target/28604] New: gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[Bug target/28604] New: gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[sje at cup dot hp dot com]

I couldn't find a report about this test failing but it works at -O2 and lower
and fails at -O3 on IA64 targets.  By inlining foo into main I can make the
test fail at -O2.  Here is a smaller test case, it prints "36, 40, 44, 0" at
-O1 and lower and prints "18, 20, 44, 0" at -O2 and higher.  The -O2 results
are wrong.

typedef float v4sf __attribute__ ((vector_size (16)));
union { v4sf v; float f[4]; } v;
int main (void)
{
  unsigned int i;
  for (i = 0; i < 2; i++)
    v.v += (v4sf) { 18.0, 20.0, 22 };
  printf("%g, %g, %g, %d\n", (double) v.f[0], (double) v.f[1], (double) v.f[2],
(double) v.f[3]);
}


-- 
           Summary: gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: sje at cup dot hp dot com
GCC target triplet: ia64-*-*


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[jsm28 at gcc dot gnu dot org]

------- Comment #1 from jsm28 at gcc dot gnu dot org  2006-09-07 14:38 -------
This bug appeared on 4.1 branch between 20060718 (revision 115546) and 20060721
(revision 115639), so a regression.


-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2006-09-07 14:38:42
               date|                            |
            Summary|gcc.c-                      |[4.1/4.2 Regression] gcc.c-
                   |torture/execute/20050604-1.c|torture/execute/20050604-1.c
                   |fails on IA64 at -O3        |fails on IA64 at -O3
   Target Milestone|---                         |4.1.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[bonzini at gnu dot org]

------- Comment #2 from bonzini at gnu dot org  2006-09-09 13:05 -------
Janis, could you do a binary search?  On 4.1 branch the bug was not in r115546,
and was there in r115639.

Thanks.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[bonzini at gnu dot org]

------- Comment #3 from bonzini at gnu dot org  2006-09-09 13:06 -------
Janis, could you do a binary search?  On 4.1 branch the bug was not in r115546,
and was there in r115639.

Thanks.


-- 

bonzini at gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |janis at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[janis at gcc dot gnu dot org]

------- Comment #4 from janis at gcc dot gnu dot org  2006-09-11 16:19 -------
Sorry, I don't have an ia64 system on which to try wrong-code tests.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[sje at cup dot hp dot com]

------- Comment #5 from sje at cup dot hp dot com  2006-09-11 17:12 -------
I will see if I can find the checkin on the 4.1 branch that caused the failure.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[sje at cup dot hp dot com]

------- Comment #6 from sje at cup dot hp dot com  2006-09-11 20:39 -------
It looks like this failure was introduced with r115620.


+2006-07-20  Paul Brook  <paul@codesourcery.com>
+
+       Backport from mainline.
+       PR 27363
+       * cse.c (cse_insn): Add destination addresses to hash table. Check if
+       they are invalidated by this instruction.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[sje at cup dot hp dot com]

------- Comment #7 from sje at cup dot hp dot com  2006-09-20 21:23 -------
This bug is weird.  If I remove the code in cse_insn where the dest_addr_elt
field is used, I still get the bug.  So the problem occurs when creating the
dest_addr_elt data, not when using it.  This makes no sense to me, but that is
what I see.  I built with --enable-checking=all to see if it caught any data
corruption or bad field accesses but I didn't get any errors.  I am not sure
what to try next.

Paul, do you have any idea why your changes would affect a compilation if we
create dest_addr_elt but don't use it?


-- 

sje at cup dot hp dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pbrook at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[mmitchel at gcc dot gnu dot org]

-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[pbrook at gcc dot gnu dot org]

------- Comment #8 from pbrook at gcc dot gnu dot org  2006-09-20 22:55 -------
IIRC my change can cause entries to be present into the hash table that
wouldn't have been there before. However this should be harmless.  I don't have
any helpful suggestons why this is broken.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604

[Bug target/28604] [4.1/4.2 Regression] gcc.c-torture/execute/20050604-1.c fails on IA64 at -O3

[sje at cup dot hp dot com]

------- Comment #9 from sje at cup dot hp dot com  2006-10-03 17:42 -------
I submitted a patch for this defect,
http://gcc.gnu.org/ml/gcc-patches/2006-09/msg01108.html
however the failure seems to have gone away even without applying this patch.
I think (but did not verify) that this patch went away due to this fix by
Roger Sayle:
http://gcc.gnu.org/ml/gcc-patches/2006-09/msg00456.html

Since the failure no longer happens I am closing the defect as fixed.


-- 

sje at cup dot hp dot com changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28604