[Bug middle-end/58418] New: wrong code at -O2 and -O3 on x86_64-linux-gnu (in 32-bit mode)

[Bug middle-end/58418] New: wrong code at -O2 and -O3 on x86_64-linux-gnu (in 32-bit mode)

[su at cs dot ucdavis.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58418

            Bug ID: 58418
           Summary: wrong code at -O2 and -O3 on x86_64-linux-gnu (in
                    32-bit mode)
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu

The current gcc trunk produces wrong code for the attached testcase on
x86_64-linux-gnu when compiled at -O2 and -O3 in 32-bit mode. 

It appears to be a regression from 4.8.x.  


$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/4.9.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-trunk/configure
--enable-languages=c,c++,objc,obj-c++,fortran,lto
--with-gmp=/usr/local/gcc-trunk --with-mpfr=/usr/local/gcc-trunk
--with-mpc=/usr/local/gcc-trunk --with-cloog=/usr/local/gcc-trunk
--prefix=/usr/local/gcc-trunk
Thread model: posix
gcc version 4.9.0 20130913 (experimental) [trunk revision 202556] (GCC) 
$
$ gcc-trunk -m32 -O1 small.c
$ a.out
0
$ gcc-4.8 -m32 -O2 small.c  
$ a.out
0
$ gcc-trunk -m64 -O2 small.c
$ a.out
0
$ gcc-trunk -m32 -O2 small.c
$ a.out
1
$ 


------------------------------------------


int printf (const char *, ...);

int a, b, *c = &b, d = -1, e, f, *g, *h = &f, **i = &g, j;

unsigned int
foo (unsigned int p)
{
  return p == 0 ? 0 : 1 / p;
}

static int *
bar ()
{
  *c = *h = foo (d) & (-9 < d);
  for (e = 0; e; e++)
    ;
  return 0;
}

int
main ()
{
  for (; j; j++)
    for (;; a--)
      ;
  *i = bar ();
  printf ("%d\n", f);
  return 0;
}

[Bug middle-end/58418] [4.9 Regression] wrong code at -O2 and -O3 on x86_64-linux-gnu (in 32-bit mode)

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58418

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-09-13
                 CC|                            |vmakarov at redhat dot com
   Target Milestone|---                         |4.9.0
            Summary|wrong code at -O2 and -O3   |[4.9 Regression] wrong code
                   |on x86_64-linux-gnu (in     |at -O2 and -O3 on
                   |32-bit mode)                |x86_64-linux-gnu (in 32-bit
                   |                            |mode)
     Ever confirmed|0                           |1

--- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> ---
It is caused by r202468.

[Bug middle-end/58418] [4.9 Regression] wrong code at -O2 and -O3 on x86_64-linux-gnu (in 32-bit mode)

[vmakarov at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58418

--- Comment #2 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
Author: vmakarov
Date: Mon Sep 16 15:12:22 2013
New Revision: 202630

URL: http://gcc.gnu.org/viewcvs?rev=202630&root=gcc&view=rev
Log:
2013-09-16  Vladimir Makarov  <vmakarov@redhat.com>

    PR middle-end/58418
    * lra-constraints.c (undo_optional_reloads): Consider all optional
    reload even if it did not get a hard reg.

2013-09-16  Vladimir Makarov  <vmakarov@redhat.com>

    * gcc.target/i386/pr58418.c: New.


Added:
    trunk/gcc/testsuite/gcc.target/i386/pr58418.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/lra-constraints.c
    trunk/gcc/testsuite/ChangeLog

[Bug middle-end/58418] [4.9 Regression] wrong code at -O2 and -O3 on x86_64-linux-gnu (in 32-bit mode)

[law at redhat dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58418

--- Comment #3 from Jeffrey A. Law <law at redhat dot com> ---
*** Bug 58431 has been marked as a duplicate of this bug. ***

[Bug middle-end/58418] [4.9 Regression] wrong code at -O2 and -O3 on x86_64-linux-gnu (in 32-bit mode)

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58418

Richard Biener <rguenth at gcc dot gnu.org> changed:

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

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.

[Bug middle-end/58418] [4.9 Regression] wrong code at -O2 and -O3 on x86_64-linux-gnu (in 32-bit mode)

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58418

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
*** Bug 58419 has been marked as a duplicate of this bug. ***