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* [Bug middle-end/21862] New: strength reduction uses signed comparisons for pointers
@ 2005-06-01 13:10 jakub at gcc dot gnu dot org
  2005-06-01 13:11 ` [Bug middle-end/21862] " jakub at gcc dot gnu dot org
  2005-06-01 13:18 ` pinskia at gcc dot gnu dot org
  0 siblings, 2 replies; 3+ messages in thread
From: jakub at gcc dot gnu dot org @ 2005-06-01 13:10 UTC (permalink / raw)
  To: gcc-bugs

The attached testcase fails on i386-linux (as well as x86_64-linux -m32).
It computes the p + (MAP_LEN / 0x100) * 0x100 end pointer, but instead of
doing unsigned comparison on the pointers, it does a signed one,
which obviously doesn't work if the pointer has topmost bit set.

-- 
           Summary: strength reduction uses signed comparisons for pointers
           Product: gcc
           Version: 3.4.4
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jakub at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
GCC target triplet: i386-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21862


^ permalink raw reply	[flat|nested] 3+ messages in thread
* [Bug middle-end/21862] strength reduction uses signed comparisons for pointers
  2005-06-01 13:10 [Bug middle-end/21862] New: strength reduction uses signed comparisons for pointers jakub at gcc dot gnu dot org
@ 2005-06-01 13:11 ` jakub at gcc dot gnu dot org
  2005-06-01 13:18 ` pinskia at gcc dot gnu dot org
  1 sibling, 0 replies; 3+ messages in thread
From: jakub at gcc dot gnu dot org @ 2005-06-01 13:11 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From jakub at gcc dot gnu dot org  2005-06-01 13:10 -------
Created an attachment (id=9007)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=9007&action=view)
testcase


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21862


^ permalink raw reply	[flat|nested] 3+ messages in thread
* [Bug middle-end/21862] strength reduction uses signed comparisons for pointers
  2005-06-01 13:10 [Bug middle-end/21862] New: strength reduction uses signed comparisons for pointers jakub at gcc dot gnu dot org
  2005-06-01 13:11 ` [Bug middle-end/21862] " jakub at gcc dot gnu dot org
@ 2005-06-01 13:18 ` pinskia at gcc dot gnu dot org
  1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-06-01 13:18 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2005-06-01 13:18 -------
This is a known bug, see gcc.c-torture/execute/loop-2e.c.
This is a dup of bug 16052.

*** This bug has been marked as a duplicate of 16052 ***

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21862


^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2005-06-01 13:18 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2005-06-01 13:10 [Bug middle-end/21862] New: strength reduction uses signed comparisons for pointers jakub at gcc dot gnu dot org
2005-06-01 13:11 ` [Bug middle-end/21862] " jakub at gcc dot gnu dot org
2005-06-01 13:18 ` pinskia at gcc dot gnu dot org

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