add compiler-rt files for 64-bit math

1 files changed, 31 insertions, 0 deletions

diff --git a/system/lib/compiler-rt/divdi3.c b/system/lib/compiler-rt/divdi3.c
new file mode 100644
index 00000000..2c2bcc26
--- /dev/null
+++ b/system/lib/compiler-rt/divdi3.c
@@ -0,0 +1,31 @@
+/* ===-- divdi3.c - Implement __divdi3 -------------------------------------===
+ *
+ *                     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 __divdi3 for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+du_int COMPILER_RT_ABI __udivmoddi4(du_int a, du_int b, du_int* rem);
+
+/* Returns: a / b */
+
+COMPILER_RT_ABI di_int
+__divdi3(di_int a, di_int b)
+{
+    const int bits_in_dword_m1 = (int)(sizeof(di_int) * CHAR_BIT) - 1;
+    di_int s_a = a >> bits_in_dword_m1;           /* s_a = a < 0 ? -1 : 0 */
+    di_int s_b = b >> bits_in_dword_m1;           /* s_b = b < 0 ? -1 : 0 */
+    a = (a ^ s_a) - s_a;                         /* negate if s_a == -1 */
+    b = (b ^ s_b) - s_b;                         /* negate if s_b == -1 */
+    s_a ^= s_b;                                  /*sign of quotient */
+    return (__udivmoddi4(a, b, (du_int*)0) ^ s_a) - s_a;  /* negate if s_a == -1 */
+}