[APInt] Add the truncOrSelf resizing operator to APInt

Truncates the APInt if the bit width is greater than the width specified,
otherwise do nothing

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D91445

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/Support/APInt.cpp b/llvm/lib/Support/APInt.cpp
index fc339de..12ceb2d 100644
--- a/llvm/lib/Support/APInt.cpp
+++ b/llvm/lib/Support/APInt.cpp
@@ -961,6 +961,12 @@ APInt APInt::sextOrTrunc(unsigned width) const {
   return *this;
 }
 
+APInt APInt::truncOrSelf(unsigned width) const {
+  if (BitWidth > width)
+    return trunc(width);
+  return *this;
+}
+
 APInt APInt::zextOrSelf(unsigned width) const {
   if (BitWidth < width)
     return zext(width);