* combine.c (distribute_notes): Cancel REG_VALUE_PROFILE notes.
	* gcov-io.h (GCOV_FIRST_VALUE_COUNTER, GCOV_LAST_VALUE_COUNTER,
	GCOV_N_VALUE_COUNTERS): New.
	* profile.c (compute_value_histograms): New static function.
	(branch_prob): Read back the value histograms.
	* rtl.c (reg_note_name): Add name for REG_VALUE_PROFILE note.
	* rtl.h (enum reg_note): Add REG_VALUE_PROFILE note.
	* value-prof.c: Add comment on reading the profile.
	* value-prof.h (COUNTER_FOR_HIST_TYPE, HIST_TYPE_FOR_COUNTER): New.
	* doc/invoke.texi (-fprofile-values): Document behavior with
	-fbranch-probabilities.

From-SVN: r69969