Minor cleanup. Use dyn_cast, not isa/cast pairs. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60623 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 187af66cdb5e0a95b2cd663107fcab1afded3e98..2b714de3b3fac130bb8c2edb6d2c4fced74a79fa 100644 (file)
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -2911,18 +2911,18 @@ bool ScalarEvolutionsImpl::potentialInfiniteLoop(SCEV *Stride, SCEV *RHS,
                                                  bool isSigned, bool trueWhenEqual) {
   // Return true when the distance from RHS to maxint > Stride.
 
-  if (!isa<SCEVConstant>(Stride))
+  SCEVConstant *SC = dyn_cast<SCEVConstant>(Stride);
+  if (!SC)
     return true;
-  SCEVConstant *SC = cast<SCEVConstant>(Stride);
 
   if (SC->getValue()->isZero())
     return true;
   if (!trueWhenEqual && SC->getValue()->isOne())
     return false;
 
-  if (!isa<SCEVConstant>(RHS))
+  SCEVConstant *R = dyn_cast<SCEVConstant>(RHS);
+  if (!R)
     return true;
-  SCEVConstant *R = cast<SCEVConstant>(RHS);
 
   if (isSigned)
     return true;  // XXX: because we don't have an sdiv scev.
@@ -2983,7 +2983,7 @@ HowManyLessThans(SCEV *LHS, SCEV *RHS, const Loop *L,
     // loop by one iteration.
     //
     // The loop won't actually run (m-n)/s times because the loop iterations
-    // won't divide evenly. For example, if you have {2,+,5} u< 10 the
+    // might not divide cleanly. For example, if you have {2,+,5} u< 10 the
     // division would equal one, but the loop runs twice putting the
     // induction variable at 12.