This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
optimization/7909: ia64 warning 'Use of 'mov' may violate WAW dependency' on -O2 and above
- From: ben at zeus dot com
- To: gcc-gnats at gcc dot gnu dot org
- Date: 13 Sep 2002 13:38:45 -0000
- Subject: optimization/7909: ia64 warning 'Use of 'mov' may violate WAW dependency' on -O2 and above
- Reply-to: ben at zeus dot com
>Number: 7909
>Category: optimization
>Synopsis: ia64 warning 'Use of 'mov' may violate WAW dependency' on -O2 and above
>Confidential: no
>Severity: non-critical
>Priority: medium
>Responsible: unassigned
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Fri Sep 13 06:46:02 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator: Ben
>Release: 3.2
>Organization:
>Environment:
Compiling native code for a ia64 box
>Description:
The code sample is a fairly ugly routine to convert pointers
into a hex string. The code compiles fine with all levels of
optimisation. However, with -O2 and above, gcc reports the
following warning messages:
/tmp/cc2HCufe.s: Assembler messages:
/tmp/cc2HCufe.s:133: Warning: Use of 'mov' may violate WAW dependency 'GR%, % in 1 - 127' (impliedf), specific resource number is 14
/tmp/cc2HCufe.s:133: Warning: Only the first path encountering the conflict is reported
>How-To-Repeat:
Compile the code with -O2 or above. No other compile flags required.
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: text/x-csrc; name="gccia64.c"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="gccia64.c"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