vendor/compiler-rt/compiler-rt-r224034

1 files changed, 44 insertions, 0 deletions

diff --git a/lib/builtins/fixunsdfsi.c b/lib/builtins/fixunsdfsi.c
new file mode 100644
index 0000000000000..c6a3c755e90f5
--- /dev/null
+++ b/lib/builtins/fixunsdfsi.c
@@ -0,0 +1,44 @@
+/* ===-- fixunsdfsi.c - Implement __fixunsdfsi -----------------------------===
+ *
+ *                     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 __fixunsdfsi for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+/* Returns: convert a to a unsigned int, rounding toward zero.
+ *          Negative values all become zero.
+ */
+
+/* Assumption: double is a IEEE 64 bit floating point type 
+ *             su_int is a 32 bit integral type
+ *             value in double is representable in su_int or is negative 
+ *                 (no range checking performed)
+ */
+
+/* seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */
+
+ARM_EABI_FNALIAS(d2uiz, fixunsdfsi)
+
+COMPILER_RT_ABI su_int
+__fixunsdfsi(double a)
+{
+    double_bits fb;
+    fb.f = a;
+    int e = ((fb.u.s.high & 0x7FF00000) >> 20) - 1023;
+    if (e < 0 || (fb.u.s.high & 0x80000000))
+        return 0;
+    return (
+                0x80000000u                      |
+                ((fb.u.s.high & 0x000FFFFF) << 11) |
+                (fb.u.s.low >> 21)
+           ) >> (31 - e);
+}