value-prof.c: New.

	* value-prof.c: New.
	* value-prof.h: New.
	* Makefile.in (value-prof.o): New.
	(LIBGCOV): Add _gcov_merge_single and _gcov_merge_delta
	(profile.o): Add value-prof.h and tree.h dependency.
	* flags.h (flag_profile_values): Declare.
	* gcov-io.h (GCOV_COUNTERS, GCOV_COUNTER_NAMES, GCOV_MERGE_FUNCTIONS):
	Add new counters.
	(GCOV_COUNTER_V_INTERVAL, GCOV_COUNTER_V_POW2, GCOV_COUNTER_V_SINGLE,
	GCOV_COUNTER_V_DELTA): New counter sections.
	(__gcov_merge_single, __gcov_merge_delta): Declare.
	* flow.c (mark_used_regs): Set subregs_of_mode only when the
	structure is initialized.
	* libgcov.c (__gcov_merge_single, __gcov_merge_delta): New functions.
	* profile.c: Include value-prof.h and tree.h.
	(gen_interval_profiler, gen_pow2_profiler, gen_one_value_profiler,
	gen_const_delta_profiler, instrument_values): New static functions.
	(get_exec_counts): Fix comment.
	(branch_prob): Invoke instrument_values.
	* toplev.c (flag_profile_values): New flag.
	* doc/invoke.texi (-fprofile-values): Document.

From-SVN: r68519