TAU_PROFILE_STMT — Executes a statement only when TAU is used.
TAU_PROFILE_STMT executes a statement, or declares
a variable that is used only during profiling or for execution of a
statement that takes place only when the instrumentation is active. When
instrumentation is inactive (i.e., when profiling and tracing are turned
off as described in Chapter 2), all macros are defined as null.