Move original compiler-rt functions (libgcc replacement) to lib/builtins directory

llvm-svn: 201393

1 files changed, 45 insertions, 0 deletions

diff --git a/compiler-rt/lib/builtins/fixsfti.c b/compiler-rt/lib/builtins/fixsfti.c
new file mode 100644
index 00000000000..c730ae0467c
--- /dev/null
+++ b/compiler-rt/lib/builtins/fixsfti.c
@@ -0,0 +1,45 @@
+/* ===-- fixsfti.c - Implement __fixsfti -----------------------------------===
+ *
+ *                     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 __fixsfti for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+#if __x86_64
+
+/* Returns: convert a to a signed long long, rounding toward zero. */
+
+/* Assumption: float is a IEEE 32 bit floating point type 
+ *             su_int is a 32 bit integral type
+ *             value in float is representable in ti_int (no range checking performed)
+ */
+
+/* seee eeee emmm mmmm mmmm mmmm mmmm mmmm */
+
+ti_int
+__fixsfti(float a)
+{
+    float_bits fb;
+    fb.f = a;
+    int e = ((fb.u & 0x7F800000) >> 23) - 127;
+    if (e < 0)
+        return 0;
+    ti_int s = (si_int)(fb.u & 0x80000000) >> 31;
+    ti_int r = (fb.u & 0x007FFFFF) | 0x00800000;
+    if (e > 23)
+        r <<= (e - 23);
+    else
+        r >>= (23 - e);
+    return (r ^ s) - s;
+}
+
+#endif