1 files changed, 47 insertions, 0 deletions
diff --git a/lib/builtins/fixunssfti.c b/lib/builtins/fixunssfti.c
new file mode 100644
index 000000000000..4da9e242ad05
--- /dev/null
+++ b/lib/builtins/fixunssfti.c
@@ -0,0 +1,47 @@
+/* ===-- fixunssfti.c - Implement __fixunssfti -----------------------------===
+ *
+ *                     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 implements __fixunssfti for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+#ifdef CRT_HAS_128BIT
+
+/* Returns: convert a to a unsigned long long, rounding toward zero.
+ *          Negative values all become zero.
+ */
+
+/* Assumption: float is a IEEE 32 bit floating point type 
+ *             tu_int is a 64 bit integral type
+ *             value in float is representable in tu_int or is negative 
+ *                 (no range checking performed)
+ */
+
+/* seee eeee emmm mmmm mmmm mmmm mmmm mmmm */
+
+COMPILER_RT_ABI tu_int
+__fixunssfti(float a)
+{
+    float_bits fb;
+    fb.f = a;
+    int e = ((fb.u & 0x7F800000) >> 23) - 127;
+    if (e < 0 || (fb.u & 0x80000000))
+        return 0;
+    tu_int r = (fb.u & 0x007FFFFF) | 0x00800000;
+    if (e > 23)
+        r <<= (e - 23);
+    else
+        r >>= (23 - e);
+    return r;
+}
+
+#endif /* CRT_HAS_128BIT */