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optimization/7908: 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 13:36:05 -0000
- Subject: optimization/7908: ia64 warning 'Use of 'mov' may violate WAW dependency' on -O2 and above
- Reply-to: ben at zeus dot com
>Number: 7908
>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 06:46:01 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:
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