Compiling the program

The steps for compiling a program for flow profiling are basically the same as those described for prof.

Whether you are using flow profile logs for performance analysis or for locality tuning, the procedure is the same. However, when compiling for locality tuning, it is strongly recommended that every source file that is part of the object to be tuned be compiled for flow profiling. This is not necessary if the data is to be used for performance analysis.

You must compile your source files with the -qf option to create flow profile logs. Using the same example described previously:

$ cc -qf -o travel travel.c misc.c

As noted earlier, if you compile and link your program in separate steps, you must specify -qf when you link as well as when you compile:

   $ cc -qf -c travel.c
   $ cc -qf -c misc.c
   $ cc -qf -o travel travel.o misc.o

Alternatively, if recompiling your program is not convenient, you can use fur to insert profiling code into your objects.

   $ fur -p all -e all travel.o
   $ fur -p all -e all misc.o
   $ cc -qf -o travel travel.o misc.o

   $ cc -qf -c travel.c
   $ cc -c misc.c
   $ cc -qf -o travel travel.o misc.o

For shared objects, the steps are quite similar:

   $ cc -qf -c travel.c
   $ cc -c misc.c
   $ cc -G -o libtravel.so -qf travel.o misc.o

For this example, any program that is compiled with libtravel.so will automatically log events whenever code in travel.c is used.