Generalize get_most_common_single_value to return n_th value & count

Currently get_most_common_single_value could only return the max hist
<value, count>, add sort after reading from disk, then it return nth value
in later use.  Rename it to get_nth_most_common_value.

gcc/ChangeLog:

2019-07-15  Xiong Hu Luo  <luoxhu@linux.ibm.com>

	* ipa-profile.c (get_most_common_single_value): Use
	get_nth_most_common_value.
	* profile.c (sort_hist_value): New function.
	(compute_value_histograms): Call sort_hist_value to sort the
	values after loading from disk.
	* value-prof.c (get_most_common_single_value): Rename to ...
	get_nth_most_common_value.  Add input params n, return
	the n_th value and count.
	(gimple_divmod_fixed_value_transform): Use
	get_nth_most_common_value.
	(gimple_ic_transform): Likewise.
	(gimple_stringops_transform): Likewise.
	* value-prof.h (get_most_common_single_value): Add input params
	n, default to 0.

From-SVN: r273789

1 files changed, 4 insertions, 5 deletions

diff --git a/gcc/value-prof.h b/gcc/value-prof.h
index ca846d0..1078722 100644
--- a/gcc/value-prof.h
+++ b/gcc/value-prof.h
@@ -89,11 +89,10 @@ void free_histograms (function *);
 void stringop_block_profile (gimple *, unsigned int *, HOST_WIDE_INT *);
 gcall *gimple_ic (gcall *, struct cgraph_node *, profile_probability);
 bool check_ic_target (gcall *, struct cgraph_node *);
-bool get_most_common_single_value (gimple *stmt, const char *counter_type,
-				   histogram_value hist,
-				   gcov_type *value, gcov_type *count,
-				   gcov_type *all);
-
+bool get_nth_most_common_value (gimple *stmt, const char *counter_type,
+				histogram_value hist, gcov_type *value,
+				gcov_type *count, gcov_type *all,
+				unsigned n = 0);
 
 /* In tree-profile.c.  */
 extern void gimple_init_gcov_profiler (void);