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 25 DEFINE_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 40
