X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FConstantRange.cpp;h=265b6e96a74698486da4881795f8d986bc985faf;hb=ce30a8106d7d33af9c18518c11e808eaeebc2cce;hp=d770381dcd5a3f784a4dadc8fdde3f5f4adffb71;hpb=318b7cc7f10d41370929ff93274de29c11f87b81;p=oota-llvm.git

diff --git a/lib/Support/ConstantRange.cpp b/lib/Support/ConstantRange.cpp
index d770381dcd5..265b6e96a74 100644
--- a/lib/Support/ConstantRange.cpp
+++ b/lib/Support/ConstantRange.cpp
@@ -144,9 +144,6 @@ bool ConstantRange::isSignWrappedSet() const {
 /// getSetSize - Return the number of elements in this set.
 ///
 APInt ConstantRange::getSetSize() const {
-  if (isEmptySet())
-    return APInt(getBitWidth()+1, 0);
-
   if (isFullSet()) {
     APInt Size(getBitWidth()+1, 0);
     Size.setBit(getBitWidth());
@@ -433,7 +430,7 @@ ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
     APInt LowerExt(DstTySize, 0);
     if (!Upper) // special case: [X, 0) -- not really wrapping around
       LowerExt = Lower.zext(DstTySize);
-    return ConstantRange(LowerExt, APInt(DstTySize, 1).shl(SrcTySize));
+    return ConstantRange(LowerExt, APInt::getOneBitSet(DstTySize, SrcTySize));
   }
 
   return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize));
@@ -448,6 +445,11 @@ ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const {
 
   unsigned SrcTySize = getBitWidth();
   assert(SrcTySize < DstTySize && "Not a value extension");
+
+  // special case: [X, INT_MIN) -- not really wrapping around
+  if (Upper.isMinSignedValue())
+    return ConstantRange(Lower.sext(DstTySize), Upper.zext(DstTySize));
+
   if (isFullSet() || isSignWrappedSet()) {
     return ConstantRange(APInt::getHighBitsSet(DstTySize,DstTySize-SrcTySize+1),
                          APInt::getLowBitsSet(DstTySize, SrcTySize-1) + 1);