Fix bad APInt compare.

APInt comparison require both to have the same bitwidth.  Since only the value
is needed, use the compare function APInt::isSameValue instead.

llvm-svn: 372454
diff --git a/clang/lib/AST/Expr.cpp b/clang/lib/AST/Expr.cpp
index b5fb7fa..c9394bb 100644
--- a/clang/lib/AST/Expr.cpp
+++ b/clang/lib/AST/Expr.cpp
@@ -3983,7 +3983,8 @@
         const auto Integer1 = dyn_cast<IntegerLiteral>(Idx1);
         const auto Integer2 = dyn_cast<IntegerLiteral>(Idx2);
         if (Integer1 && Integer2) {
-          if (Integer1->getValue() != Integer2->getValue())
+          if (!llvm::APInt::isSameValue(Integer1->getValue(),
+                                        Integer2->getValue()))
             return false;
         } else {
           if (!isSameComparisonOperand(Idx1, Idx2))