[llvm-profdata] add value-cutoff functionality in show command

This patch improves llvm-profdata show command:
(1) add -value-cutoff=<N> option: Show only those functions whose max count
    values are greater or equal to N.
(2) add -list-below-cutoff option: Only output names of functions whose max
    count value are below the cutoff.
(3) formats value-profile counts and prints out percentage.

Differential Revision: https://reviews.llvm.org/D56342

llvm-svn: 350673
diff --git a/llvm/docs/CommandGuide/llvm-profdata.rst b/llvm/docs/CommandGuide/llvm-profdata.rst
index 96c91e3..f66fb49 100644
--- a/llvm/docs/CommandGuide/llvm-profdata.rst
+++ b/llvm/docs/CommandGuide/llvm-profdata.rst
@@ -203,7 +203,7 @@
  annotations.
 
 .. option:: -topn=n
-	     
+
  Instruct the profile dumper to show the top ``n`` functions with the
  hottest basic blocks in the summary section. By default, the topn functions
  are not dumped.
@@ -216,6 +216,16 @@
 
  Show the profiled sizes of the memory intrinsic calls for shown functions.
 
+.. option:: -value-cutoff=n
+
+ Show only those functions whose max count values are greater or equal to ``n``.
+ By default, the value-cutoff is set to 0.
+
+.. option:: -list-below-cutoff
+
+ Only output names of functions whose max count value are below the cutoff
+ value.
+
 EXIT STATUS
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