compiler_rt: Import aeabi_ldivmode.S file and dependencies

Import aeabi_ldivmod.S with divmoddi4.c and divdi3.c from the
LLVM compiler_rt library on master branch as of 30 Oct 2018
(SVN revision: r345645).

This is to get the __aeabi_ldivmod builtin, which is required
by a patch using signed long long division.

Change-Id: Iee4c421deb3175142655e19074cd3732edd82227
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>

lib/compiler-rt/builtins/arm/aeabi_ldivmod.S

+//===-- aeabi_ldivmod.S - EABI ldivmod implementation ---------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+#include "../assembly.h"
+
+// struct { int64_t quot, int64_t rem}
+//        __aeabi_ldivmod(int64_t numerator, int64_t denominator) {
+//   int64_t rem, quot;
+//   quot = __divmoddi4(numerator, denominator, &rem);
+//   return {quot, rem};
+// }
+
+#if defined(__MINGW32__)
+#define __aeabi_ldivmod __rt_sdiv64
+#endif
+
+        .syntax unified
+        .p2align 2
+DEFINE_COMPILERRT_FUNCTION(__aeabi_ldivmod)
+        push    {r6, lr}
+        sub     sp, sp, #16
+        add     r6, sp, #8
+        str     r6, [sp]
+#if defined(__MINGW32__)
+        movs    r6, r0
+        movs    r0, r2
+        movs    r2, r6
+        movs    r6, r1
+        movs    r1, r3
+        movs    r3, r6
+#endif
+        bl      SYMBOL_NAME(__divmoddi4)
+        ldr     r2, [sp, #8]
+        ldr     r3, [sp, #12]
+        add     sp, sp, #16
+        pop     {r6, pc}
+END_COMPILERRT_FUNCTION(__aeabi_ldivmod)
+
+NO_EXEC_STACK_DIRECTIVE
+

lib/compiler-rt/builtins/divdi3.c

+/* ===-- 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"
+
+/* 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 */
+}

lib/compiler-rt/builtins/divmoddi4.c

+/*===-- divmoddi4.c - Implement __divmoddi4 --------------------------------===
+ *
+ *                    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 __divmoddi4 for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+/* Returns: a / b, *rem = a % b  */
+
+COMPILER_RT_ABI di_int
+__divmoddi4(di_int a, di_int b, di_int* rem)
+{
+  di_int d = __divdi3(a,b);
+  *rem = a - (d*b);
+  return d;
+}

lib/compiler-rt/compiler-rt.mk

 #
-# Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are met:
@@ -29,8 +29,11 @@
 #
 
 ifeq (${ARCH},aarch32)
-COMPILER_RT_SRCS	:=	lib/compiler-rt/builtins/arm/aeabi_uldivmod.S	\
-				lib/compiler-rt/builtins/udivmoddi4.c		\
+COMPILER_RT_SRCS	:=	lib/compiler-rt/builtins/arm/aeabi_ldivmod.S	\
+				lib/compiler-rt/builtins/arm/aeabi_uldivmod.S	\
 				lib/compiler-rt/builtins/ctzdi2.c		\
-				lib/compiler-rt/builtins/lshrdi3.c
+				lib/compiler-rt/builtins/divdi3.c		\
+				lib/compiler-rt/builtins/divmoddi4.c		\
+				lib/compiler-rt/builtins/lshrdi3.c		\
+				lib/compiler-rt/builtins/udivmoddi4.c
 endif