Replace intersectWith with maximalIntersectWith. The latter guarantees that

all values belonging to the intersection will belong to the resulting range.
The former was inconsistent about that point (either way is fine, just pick
one.) This is part of PR4545.

llvm-svn: 76289

1 files changed, 4 insertions, 5 deletions

diff --git a/llvm/lib/Analysis/LoopVR.cpp b/llvm/lib/Analysis/LoopVR.cpp
index 6854e950ef8..e4dac8f1f9b 100644
--- a/llvm/lib/Analysis/LoopVR.cpp
+++ b/llvm/lib/Analysis/LoopVR.cpp
@@ -142,14 +142,13 @@ ConstantRange LoopVR::getRange(const SCEV *S, const SCEV *T, ScalarEvolution &SE
 
     if (R.getUnsignedMin() == 0) {
       // Just because it contains zero, doesn't mean it will also contain one.
-      // Use maximalIntersectWith to get the right behaviour.
       ConstantRange NotZero(APInt(L.getBitWidth(), 1),
                             APInt::getNullValue(L.getBitWidth()));
-      R = R.maximalIntersectWith(NotZero);
+      R = R.intersectWith(NotZero);
     }
  
-    // But, the maximal intersection might still include zero. If it does, then
-    // we know it also included one.
+    // But, the intersection might still include zero. If it does, then we know
+    // it also included one.
     if (R.contains(APInt::getNullValue(L.getBitWidth())))
       Upper = L.getUnsignedMax();
     else
@@ -295,5 +294,5 @@ void LoopVR::narrow(Value *V, const ConstantRange &CR) {
   if (I == Map.end())
     Map[V] = new ConstantRange(CR);
   else
-    Map[V] = new ConstantRange(Map[V]->maximalIntersectWith(CR));
+    Map[V] = new ConstantRange(Map[V]->intersectWith(CR));
 }