[MBP] add comments and bug fix

Document the new parameter and threshod computation
model.  Also fix a bug when the threshold parameter
is set to be different from the default.

 

llvm-svn: 272749

1 files changed, 7 insertions, 6 deletions

diff --git a/llvm/lib/CodeGen/MachineBranchProbabilityInfo.cpp b/llvm/lib/CodeGen/MachineBranchProbabilityInfo.cpp
index 9e14cb621dd..fe734061837 100644
--- a/llvm/lib/CodeGen/MachineBranchProbabilityInfo.cpp
+++ b/llvm/lib/CodeGen/MachineBranchProbabilityInfo.cpp
@@ -24,15 +24,16 @@ INITIALIZE_PASS_BEGIN(MachineBranchProbabilityInfo, "machine-branch-prob",
 INITIALIZE_PASS_END(MachineBranchProbabilityInfo, "machine-branch-prob",
                     "Machine Branch Probability Analysis", false, true)
 
-cl::opt<unsigned> StaticLikelyProb(
-    "static-likely-prob",
-    cl::desc("branch probability threshold to be considered very likely"),
-    cl::init(80), cl::Hidden);
+cl::opt<unsigned>
+    StaticLikelyProb("static-likely-prob",
+                     cl::desc("branch probability threshold in percentage"
+                              "to be considered very likely"),
+                     cl::init(80), cl::Hidden);
 
 cl::opt<unsigned> ProfileLikelyProb(
     "profile-likely-prob",
-    cl::desc("branch probability threshold to be considered very likely "
-             "when profile is available"),
+    cl::desc("branch probability threshold in percentage to be considered"
+             " very likely when profile is available"),
     cl::init(51), cl::Hidden);
 
 char MachineBranchProbabilityInfo::ID = 0;