1 files changed, 74 insertions, 0 deletions
diff --git a/test/builtins/Unit/subtf3_test.c b/test/builtins/Unit/subtf3_test.c
new file mode 100644
index 0000000000000..2ab249a994c3e
--- /dev/null
+++ b/test/builtins/Unit/subtf3_test.c
@@ -0,0 +1,74 @@
+//===--------------- subtf3_test.c - Test __subtf3 ------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file tests __subtf3 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include <stdio.h>
+
+#if __LDBL_MANT_DIG__ == 113
+
+#include "fp_test.h"
+
+// Returns: a - b
+long double __subtf3(long double a, long double b);
+
+int test__subtf3(long double a, long double b,
+                 uint64_t expectedHi, uint64_t expectedLo)
+{
+    long double x = __subtf3(a, b);
+    int ret = compareResultLD(x, expectedHi, expectedLo);
+
+    if (ret){
+        printf("error in test__subtf3(%.20Lf, %.20Lf) = %.20Lf, "
+               "expected %.20Lf\n", a, b, x,
+               fromRep128(expectedHi, expectedLo));
+    }
+    return ret;
+}
+
+char assumption_1[sizeof(long double) * CHAR_BIT == 128] = {0};
+
+#endif
+
+int main()
+{
+#if __LDBL_MANT_DIG__ == 113
+    // qNaN - any = qNaN
+    if (test__subtf3(makeQNaN128(),
+                     0x1.23456789abcdefp+5L,
+                     UINT64_C(0x7fff800000000000),
+                     UINT64_C(0x0)))
+        return 1;
+    // NaN - any = NaN
+    if (test__subtf3(makeNaN128(UINT64_C(0x800030000000)),
+                     0x1.23456789abcdefp+5L,
+                     UINT64_C(0x7fff800000000000),
+                     UINT64_C(0x0)))
+        return 1;
+    // inf - any = inf
+    if (test__subtf3(makeInf128(),
+                     0x1.23456789abcdefp+5L,
+                     UINT64_C(0x7fff000000000000),
+                     UINT64_C(0x0)))
+        return 1;
+    // any - any
+    if (test__subtf3(0x1.234567829a3bcdef5678ade36734p+5L,
+                     0x1.ee9d7c52354a6936ab8d7654321fp-1L,
+                     UINT64_C(0x40041b8af1915166),
+                     UINT64_C(0xa44a7bca780a166c)))
+        return 1;
+
+#else
+    printf("skipped\n");
+
+#endif
+    return 0;
+}