1 files changed, 31 insertions, 0 deletions
diff --git a/lib/ubsan/lit_tests/Integer/usub-overflow.cpp b/lib/ubsan/lit_tests/Integer/usub-overflow.cpp
new file mode 100644
index 000000000000..357d662ad63e
--- /dev/null
+++ b/lib/ubsan/lit_tests/Integer/usub-overflow.cpp
@@ -0,0 +1,31 @@
+// RUN: %clang -DSUB_I32 -fsanitize=unsigned-integer-overflow %s -o %t && %t 2>&1 | FileCheck %s --check-prefix=SUB_I32
+// RUN: %clang -DSUB_I64 -fsanitize=unsigned-integer-overflow %s -o %t && %t 2>&1 | FileCheck %s --check-prefix=SUB_I64
+// RUN: %clang -DSUB_I128 -fsanitize=unsigned-integer-overflow %s -o %t && %t 2>&1 | FileCheck %s --check-prefix=SUB_I128
+
+#include <stdint.h>
+#include <stdio.h>
+
+int main() {
+  // These promote to 'int'.
+  (void)(uint8_t(0) - uint8_t(0x7f));
+  (void)(uint16_t(0) - uint16_t(0x7fff));
+
+#ifdef SUB_I32
+  (void)(uint32_t(1) - uint32_t(2));
+  // CHECK-SUB_I32: usub-overflow.cpp:[[@LINE-1]]:22: runtime error: unsigned integer overflow: 1 - 2 cannot be represented in type 'unsigned int'
+#endif
+
+#ifdef SUB_I64
+  (void)(uint64_t(8000000000000000000ll) - uint64_t(9000000000000000000ll));
+  // CHECK-SUB_I64: 8000000000000000000 - 9000000000000000000 cannot be represented in type 'unsigned long'
+#endif
+
+#ifdef SUB_I128
+# ifdef __SIZEOF_INT128__
+  (void)((__uint128_t(1) << 126) - (__uint128_t(1) << 127));
+# else
+  puts("__int128 not supported\n");
+# endif
+  // CHECK-SUB_I128: {{0x40000000000000000000000000000000 - 0x80000000000000000000000000000000 cannot be represented in type 'unsigned __int128'|__int128 not supported}}
+#endif
+}