[Analyzer] Clarify error messages for undefined result

Differential Revision: https://reviews.llvm.org/D30295

llvm-svn: 315462

1 files changed, 17 insertions, 3 deletions

diff --git a/clang/test/Analysis/bitwise-ops.c b/clang/test/Analysis/bitwise-ops.c
index 407aa19289c..acef6681d89 100644
--- a/clang/test/Analysis/bitwise-ops.c
+++ b/clang/test/Analysis/bitwise-ops.c
@@ -22,11 +22,25 @@ int testConstantShifts_PR18073(int which) {
   case 1:
     return 0ULL << 63; // no-warning
   case 2:
-    return 0ULL << 64; // expected-warning{{The result of the '<<' expression is undefined}}
+    return 0ULL << 64; // expected-warning{{The result of the left shift is undefined due to shifting by '64', which is greater or equal to the width of type 'unsigned long long'}}
   case 3:
-    return 0ULL << 65; // expected-warning{{The result of the '<<' expression is undefined}}
+    return 0ULL << 65; // expected-warning{{The result of the left shift is undefined due to shifting by '65', which is greater or equal to the width of type 'unsigned long long'}}
 
   default:
     return 0;
   }
-}
\ No newline at end of file
+}
+
+int testOverflowShift(int a) {
+  if (a == 323) {
+    return 1 << a; // expected-warning{{The result of the left shift is undefined due to shifting by '323', which is greater or equal to the width of type 'int'}}
+  }
+  return 0;
+}
+
+int testNegativeShift(int a) {
+  if (a == -5) {
+    return 1 << a; // expected-warning{{The result of the left shift is undefined because the right operand is negative}}
+  }
+  return 0;
+}