Code Profiling Utilities Manual

Optimizing a Program Using Profile-Guided
Optimization
HP Code Profiling Utilities Manual—542684-003
6-3
Additional Usage Considerations
Then the raw data file generated by subsequent execution of myprog.o will contain
only the name myprog.c. If -Wbasename were not specified, the full path name
/homedir/subdir/myprog.c would be included in the raw data file.
Additional Usage Considerations
•
If you do not specify the basename option, then the source files used with profuse
compilations must be in the same locations (that is, they must have the same fully-
qualified pathnames) as when the files were compiled with profgen.
•
If you specify the basename option for a particular profgen compilation, also
specify it for the profuse compilation of the same source file. Likewise, if you omit
the basename option for a particular compilation, also omit it for the profuse
compilation of the same source file.
•
Do not change the source code between the profgen compilation and the profuse
compilation.
•
Use the same version of the compiler for both compilations.
•
Use the same compiler options for both compilations (except for profgen, profuse,
and profdir).
Note. If you move a source file between an OSS directory and a Windows directory or
Guardian subvolume, then all characters in the OSS file name must be uppercase.
Note. If only a minor source code change is needed after the profgen compilation, you
can consider saving time by making the change and recompiling with profuse using the
previous DPI file. This eliminates the steps needed to recompile and create a new DPI file,
and your program will likely realize most of the benefits of profile-guided optimization.