Fix undefined behavior.

[oota-llvm.git] / lib / Support / APInt.cpp

diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp
index b5411bec9d4d5380958dc2959250c508f0593f51..0d4e0f9f752aff20b341283196aacadcb2e871b8 100644 (file)
--- a/lib/Support/APInt.cpp
+++ b/lib/Support/APInt.cpp
@@ -1123,6 +1123,18 @@ APInt APInt::sextOrTrunc(unsigned width) const {
   return *this;
 }
 
+APInt APInt::zextOrSelf(unsigned width) const {
+  if (BitWidth < width)
+    return zext(width);
+  return *this;
+}
+
+APInt APInt::sextOrSelf(unsigned width) const {
+  if (BitWidth < width)
+    return sext(width);
+  return *this;
+}
+
 /// Arithmetic right-shift this APInt by shiftAmt.
 /// @brief Arithmetic right-shift function.
 APInt APInt::ashr(const APInt &shiftAmt) const {
@@ -1222,7 +1234,7 @@ APInt APInt::lshr(const APInt &shiftAmt) const {
 /// @brief Logical right-shift function.
 APInt APInt::lshr(unsigned shiftAmt) const {
   if (isSingleWord()) {
-    if (shiftAmt == BitWidth)
+    if (shiftAmt >= BitWidth)
       return APInt(BitWidth, 0);
     else
       return APInt(BitWidth, this->VAL >> shiftAmt);