1/*===-- modsi3.S - 32-bit signed integer modulus --------------------------===//
2 *
3 * The LLVM Compiler Infrastructure
4 *
5 * This file is dual licensed under the MIT and the University of Illinois Open
6 * Source Licenses. See LICENSE.TXT for details.
7 *
8 *===----------------------------------------------------------------------===//
9 *
10 * This file implements the __modsi3 (32-bit signed integer modulus) function
11 * for the ARM architecture as a wrapper around the unsigned routine.
12 *
13 *===----------------------------------------------------------------------===*/
14
15#include "../assembly.h"
16
17#define ESTABLISH_FRAME \
18 push {r4, r7, lr} ;\
19 add r7, sp, #4
20#define CLEAR_FRAME_AND_RETURN \
21 pop {r4, r7, pc}
22
23.syntax unified
24.align 3
25DEFINE_COMPILERRT_FUNCTION(__modsi3)
26 ESTABLISH_FRAME
27 // Set aside the sign of the dividend.
28 mov r4, r0
29 // Take absolute value of a and b via abs(x) = (x^(x >> 31)) - (x >> 31).
30 eor r2, r0, r0, asr #31
31 eor r3, r1, r1, asr #31
32 sub r0, r2, r0, asr #31
33 sub r1, r3, r1, asr #31
34 // abs(a) % abs(b)
35 bl SYMBOL_NAME(__umodsi3)
36 // Apply sign of dividend to result and return.
37 eor r0, r0, r4, asr #31
38 sub r0, r0, r4, asr #31
39 CLEAR_FRAME_AND_RETURN