Update docs.

llvm-svn: 185250

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -47,8 +47,8 @@ using namespace llvm;
 
 static cl::opt<int>
     SLPCostThreshold("slp-threshold", cl::init(0), cl::Hidden,
-                     cl::desc("Only vectorize trees if the gain is above this "
-                              "number. (gain = -cost of vectorization)"));
+                     cl::desc("Only vectorize if you gain more than this "
+                              "number "));
 namespace {
 
 static const unsigned MinVecRegSize = 128;
@@ -697,7 +697,6 @@ int FuncSLP::getTreeCost_rec(ArrayRef<Value *> VL, unsigned Depth) {
     }
   }
 
-
   // Calculate the extract cost.
   unsigned ExternalUserExtractCost = 0;
   for (unsigned i = 0, e = VL.size(); i < e; ++i)