[PGO] internal option cleanups

1. Added comments for options
2. Added missing option cl::desc field
3. Uniified function filter option for graph viewing.
   Now PGO count/raw-counts share the same
   filter option: -view-bfi-func-name=.

llvm-svn: 293938

1 files changed, 12 insertions, 1 deletions

diff --git a/llvm/lib/Analysis/BlockFrequencyInfo.cpp b/llvm/lib/Analysis/BlockFrequencyInfo.cpp
index 2064be577f6..07a2a9229fd 100644
--- a/llvm/lib/Analysis/BlockFrequencyInfo.cpp
+++ b/llvm/lib/Analysis/BlockFrequencyInfo.cpp
@@ -55,7 +55,18 @@ cl::opt<unsigned>
                                 "function multiplied by this percent."));
 
 // Command line option to turn on CFG dot dump after profile annotation.
-cl::opt<bool> PGOViewCounts("pgo-view-counts", cl::init(false), cl::Hidden);
+cl::opt<bool>
+    PGOViewCounts("pgo-view-counts", cl::init(false), cl::Hidden,
+                  cl::desc("A boolean option to show CFG dag with "
+                           "block profile counts and branch probabilities "
+                           "right after PGO profile annotation step. The "
+                           "profile counts are computed using branch "
+                           "probabilities from the runtime profile data and "
+                           "block frequency propagation algorithm. To view "
+                           "the raw counts from the profile, use option "
+                           "-pgo-view-raw-counts instead. To limit graph "
+                           "display to only one function, use filtering option "
+                           "-view-bfi-func-name."));
 
 namespace llvm {