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

llvm-svn: 201393

1 files changed, 36 insertions, 0 deletions

diff --git a/compiler-rt/lib/builtins/modti3.c b/compiler-rt/lib/builtins/modti3.c
new file mode 100644
index 00000000000..752202d45e0
--- /dev/null
+++ b/compiler-rt/lib/builtins/modti3.c
@@ -0,0 +1,36 @@
+/* ===-- modti3.c - Implement __modti3 -------------------------------------===
+ *
+ *                     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 __modti3 for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+#if __x86_64
+
+tu_int __udivmodti4(tu_int a, tu_int b, tu_int* rem);
+
+/*Returns: a % b */
+
+ti_int
+__modti3(ti_int a, ti_int b)
+{
+    const int bits_in_tword_m1 = (int)(sizeof(ti_int) * CHAR_BIT) - 1;
+    ti_int s = b >> bits_in_tword_m1;  /* s = b < 0 ? -1 : 0 */
+    b = (b ^ s) - s;                   /* negate if s == -1 */
+    s = a >> bits_in_tword_m1;         /* s = a < 0 ? -1 : 0 */
+    a = (a ^ s) - s;                   /* negate if s == -1 */
+    ti_int r;
+    __udivmodti4(a, b, (tu_int*)&r);
+    return (r ^ s) - s;                /* negate if s == -1 */
+}
+
+#endif