Add some comments, and tidy up some whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70510 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 252eabe..fbfb030 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -2986,8 +2986,9 @@
///
BasicBlock *
ScalarEvolution::getPredecessorWithUniqueSuccessorForBB(BasicBlock *BB) {
- // If the block has a unique predecessor, the predecessor must have
- // no other successors from which BB is reachable.
+ // If the block has a unique predecessor, then there is no path from the
+ // predecessor to the block that does not go through the direct edge
+ // from the predecessor to the block.
if (BasicBlock *Pred = BB->getSinglePredecessor())
return Pred;
@@ -3002,10 +3003,11 @@
}
/// isLoopGuardedByCond - Test whether entry to the loop is protected by
-/// a conditional between LHS and RHS.
+/// a conditional between LHS and RHS. This is used to help avoid max
+/// expressions in loop trip counts.
bool ScalarEvolution::isLoopGuardedByCond(const Loop *L,
- ICmpInst::Predicate Pred,
- SCEV *LHS, SCEV *RHS) {
+ ICmpInst::Predicate Pred,
+ SCEV *LHS, SCEV *RHS) {
BasicBlock *Preheader = L->getLoopPreheader();
BasicBlock *PreheaderDest = L->getHeader();