[Bug c/35456] New: Different results for inlined vs. non-inlined function

[Bug c/35456] New: Different results for inlined vs. non-inlined function

[ubizjak at gmail dot com]

The testcase:

--cut here--
#include <stdio.h>

double
__attribute__ ((noinline))
test (double x)
{
  return x >= 0.0 ? x : -x;
}

double
__attribute__ ((always_inline))
test_inlined (double x)
{
  return x >= 0.0 ? x : -x;
}


int main()
{
  double x = -0.0;

  printf ("%f %f %f\n", x, test(x), test_inlined(x));
  return 0;
}
--cut here--

gcc -O2 abs.c
./a.out
-0.000000 0.000000 -0.000000


-- 
           Summary: Different results for inlined vs. non-inlined function
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ubizjak at gmail dot com
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

[Bug c/35456] Different results for inlined vs. non-inlined function

[ubizjak at gmail dot com]

------- Comment #1 from ubizjak at gmail dot com  2008-03-04 08:40 -------
Hm, -0.0 >= 0.0 is folded to TRUE, as confirmed by:

printf ("%i\n", -0.0 >= 0.0);

This produces 1.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

[Bug c/35456] Different results for inlined vs. non-inlined function

[pinskia at gmail dot com]

------- Comment #2 from pinskia at gmail dot com  2008-03-04 08:49 -------
Subject: Re:  Different results for inlined vs. non-inlined function



Sent from my iPhone

On Mar 4, 2008, at 0:40, "ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org 
 > wrote:

>
>
> ------- Comment #1 from ubizjak at gmail dot com  2008-03-04 08:40  
> -------
> Hm, -0.0 >= 0.0 is folded to TRUE, as confirmed by:
>
> printf ("%i\n", -0.0 >= 0.0);
>
> This produces 1.
>

That is correct. The noinline case is wrong. It should not be  
converted to be abs.

-- Pinski

>
> -- 
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

Re: [Bug c/35456] Different results for inlined vs. non-inlined function

[Andrew Pinski]

Sent from my iPhone

On Mar 4, 2008, at 0:40, "ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org 
 > wrote:

>
>
> ------- Comment #1 from ubizjak at gmail dot com  2008-03-04 08:40  
> -------
> Hm, -0.0 >= 0.0 is folded to TRUE, as confirmed by:
>
> printf ("%i\n", -0.0 >= 0.0);
>
> This produces 1.
>

That is correct. The noinline case is wrong. It should not be  
converted to be abs.

-- Pinski

>
> -- 
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456
>

[Bug c/35456] Different results for inlined vs. non-inlined function

[rguenth at gcc dot gnu dot org]

-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
           Keywords|                            |wrong-code
   Last reconfirmed|0000-00-00 00:00:00         |2008-03-04 09:36:51
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

[Bug c/35456] Different results for inlined vs. non-inlined function

[ubizjak at gmail dot com]

------- Comment #3 from ubizjak at gmail dot com  2008-03-04 10:01 -------
Working on a fix.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |ubizjak at gmail dot com
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2008-03-04 09:36:51         |2008-03-04 10:01:30
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

[Bug middle-end/35456] Different results for inlined vs. non-inlined function

[ubizjak at gmail dot com]

------- Comment #4 from ubizjak at gmail dot com  2008-03-04 12:41 -------
Patch at http://gcc.gnu.org/ml/gcc-patches/2008-03/msg00207.html.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |http://gcc.gnu.org/ml/gcc-
                   |                            |patches/2008-
                   |                            |03/msg00207.html
          Component|c                           |middle-end


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

[Bug middle-end/35456] Different results for inlined vs. non-inlined function

[uros at gcc dot gnu dot org]

------- Comment #5 from uros at gcc dot gnu dot org  2008-03-04 13:58 -------
Subject: Bug 35456

Author: uros
Date: Tue Mar  4 13:57:27 2008
New Revision: 132863

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=132863
Log:
        PR middle-end/35456
        * fold-const.c (fold_cond_expr_with_comparison): Prevent
        transformations for modes that have signed zeros.
        * ifcvt.c (noce_try_abs): Ditto.

testsuite/ChangeLog:

        PR middle-end/35456
        * gcc.c-torture/execute/pr35456.c: New test.


Added:
    trunk/gcc/testsuite/gcc.c-torture/execute/pr35456.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/fold-const.c
    trunk/gcc/ifcvt.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

[Bug middle-end/35456] Different results for inlined vs. non-inlined function

[uros at gcc dot gnu dot org]

------- Comment #6 from uros at gcc dot gnu dot org  2008-03-10 14:14 -------
Subject: Bug 35456

Author: uros
Date: Mon Mar 10 14:13:40 2008
New Revision: 133079

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=133079
Log:
        Backport from mainline:
        2008-03-09  Uros Bizjak  <ubizjak@gmail.com>

        PR target/35496
        * config/i386/i386.c (ix86_constant_alignment): Compute alignment using
        ALIGN_MODE_128 for VECTOR_CST and INTEGER_CST in addition to REAL_CST.

        2008-03-04  Uros Bizjak  <ubizjak@gmail.com>

        PR middle-end/35456
        * fold-const.c (fold_cond_expr_with_comparison): Prevent
        transformations for modes that have signed zeros.
        * ifcvt.c (noce_try_abs): Ditto.

testsuite/ChangeLog:

        Backport from mainline:
        2008-03-04  Uros Bizjak  <ubizjak@gmail.com>

        PR middle-end/35456
        * gcc.c-torture/execute/pr35456.c: New test.


Added:
    branches/gcc-4_3-branch/gcc/testsuite/gcc.c-torture/execute/pr35456.c
Modified:
    branches/gcc-4_3-branch/gcc/ChangeLog
    branches/gcc-4_3-branch/gcc/config/i386/i386.c
    branches/gcc-4_3-branch/gcc/fold-const.c
    branches/gcc-4_3-branch/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456

[Bug middle-end/35456] Different results for inlined vs. non-inlined function

[ubizjak at gmail dot com]

------- Comment #7 from ubizjak at gmail dot com  2008-03-10 14:16 -------
Fixed.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.3.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35456