Add r149110 back with a fix for when the vector and the int have the same
width.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149151 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp
index b5411be..c580dd3 100644
--- a/lib/Support/APInt.cpp
+++ b/lib/Support/APInt.cpp
@@ -1123,6 +1123,18 @@
   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 {