This patch adds functionality to libgcov to enable user applications to collect...

This patch adds functionality to libgcov to enable user applications to
collect profile data only in regions of interest. This is useful, for
example, to collect profile data from a long-running server only
during the time when it is serving requests.

Specifically, the new routines __gcov_reset will clear all profile counters
to zero and __gcov_dump will write out the profile information collected so
far. A global variable is used to prevent writing out the profile a
second time during exit.

2012-05-08   Teresa Johnson  <tejohnson@google.com>

	* libgcc/libgcov.c (gcov_clear, __gcov_reset): New functions.
	(__gcov_dump): Ditto.
	(gcov_dump_complete): New global variable.
	(gcov_exit): Export hidden to enable use in L_gcov_dump.
	(__gcov_flush): Outline functionality now in gcov_clear.
	* libgcc/Makefile.in (L_gcov_reset, L_gcov_dump): Define.
	* gcc/gcov-io.h (__gcov_reset, __gcov_dump): Declare.
	* gcc/doc/gcov.texi: Add note on using __gcov_reset and __gcov_dump.

From-SVN: r187297