RE: Problem with patch for PR tree-optimization/29789

["Fu, Chao-Ying" <fu at mips dot com>]

> -----Original Message-----
> From: gcc-owner@gcc.gnu.org [mailto:gcc-owner@gcc.gnu.org]On Behalf Of
> H. J. Lu
> Sent: Wednesday, April 25, 2007 2:02 PM
> To: Steve Ellcey
> Cc: richard.guenther@gmail.com; gcc@gcc.gnu.org
> Subject: Re: Problem with patch for PR tree-optimization/29789
> 
> 
> On Wed, Apr 25, 2007 at 01:55:14PM -0700, Steve Ellcey wrote:
> > Richard,
> > 
> > Has anyone reported any problems with your 
> tree-ssa-loop-im.c patch that
> > fixes PR tree-optimization/29789?  I have been looking at a 
> failure with
> > the SPECfp2000 173.applu test.  I found that if I compile it with
> > version r124041 of the GCC gfortran compiler it works but 
> if I compile
> > it with version r124042 it fails.  The difference between the two is
> > your checkin:
> > 
> 
> See
> 
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31703
> 
> 
> H.J.
> 

I got a test that fails for mips32r2-elf.  Is this fail from the same issue?

(bug74.c)
void test (long long mod, long long temp)
{
  while (1)
    {
      int leftmost = (mod >> 1) & 1;
      mod = mod << 1;
      if (leftmost)
        mod = temp;
    }
}

# mipsisa32r2-elf-gcc -S bug74.c -O -fdump-tree-all
bug74.c: In function â?~testâ?T:
bug74.c:5: internal compiler error: in simplify_subreg, at simplify-rtx.c:4677
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

(bug74.c.119t.blocks)

;; Function test (test)

test (mod, temp)
{
  long long int mod.25;
  int leftmost;

<L3>:;

<L4>:;
  mod.25 = mod;

<L6>:;
  leftmost = mod.25 & 2;
  mod.25 = mod.25 << 1;
  mod = temp;
  if (leftmost != 0) goto <L4>; else goto <L6>;

}

NOTE that there should be a type cast to int for this statement
"leftmost = mod.25 & 2;".

Regards,
Chao-ying