update file comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44543 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/SimplifyCFG.cpp b/lib/Transforms/Scalar/SimplifyCFG.cpp
index ed51746..259f4d1 100644
--- a/lib/Transforms/Scalar/SimplifyCFG.cpp
+++ b/lib/Transforms/Scalar/SimplifyCFG.cpp
@@ -7,14 +7,17 @@
//
//===----------------------------------------------------------------------===//
//
-// This file implements dead code elimination and basic block merging.
-// Specifically:
+// This file implements dead code elimination and basic block merging, along
+// with a collection of other peephole control flow optimizations. For example:
//
// * Removes basic blocks with no predecessors.
// * Merges a basic block into its predecessor if there is only one and the
// predecessor only has one successor.
// * Eliminates PHI nodes for basic blocks with a single predecessor.
// * Eliminates a basic block that only contains an unconditional branch.
+// * Changes invoke instructions to nounwind functions to be calls.
+// * Change things like "if (x) if (y)" into "if (x&y)".
+// * etc..
//
//===----------------------------------------------------------------------===//