1*0b57cec5SDimitry Andric//===-- modsi3.S - 32-bit signed integer modulus --------------------------===// 2*0b57cec5SDimitry Andric// 3*0b57cec5SDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*0b57cec5SDimitry Andric// See https://llvm.org/LICENSE.txt for license information. 5*0b57cec5SDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*0b57cec5SDimitry Andric// 7*0b57cec5SDimitry Andric//===----------------------------------------------------------------------===// 8*0b57cec5SDimitry Andric// 9*0b57cec5SDimitry Andric// This file implements the __modsi3 (32-bit signed integer modulus) function 10*0b57cec5SDimitry Andric// for the ARM architecture as a wrapper around the unsigned routine. 11*0b57cec5SDimitry Andric// 12*0b57cec5SDimitry Andric//===----------------------------------------------------------------------===// 13*0b57cec5SDimitry Andric 14*0b57cec5SDimitry Andric#include "../assembly.h" 15*0b57cec5SDimitry Andric 16*0b57cec5SDimitry Andric#define ESTABLISH_FRAME \ 17*0b57cec5SDimitry Andric push {r4, r7, lr} ;\ 18*0b57cec5SDimitry Andric add r7, sp, #4 19*0b57cec5SDimitry Andric#define CLEAR_FRAME_AND_RETURN \ 20*0b57cec5SDimitry Andric pop {r4, r7, pc} 21*0b57cec5SDimitry Andric 22*0b57cec5SDimitry Andric .syntax unified 23*0b57cec5SDimitry Andric .text 24*0b57cec5SDimitry Andric DEFINE_CODE_STATE 25*0b57cec5SDimitry Andric 26*0b57cec5SDimitry Andric@ int __modsi3(int divident, int divisor) 27*0b57cec5SDimitry Andric@ Calculate and return the remainder of the (signed) division. 28*0b57cec5SDimitry Andric 29*0b57cec5SDimitry Andric .p2align 3 30*0b57cec5SDimitry AndricDEFINE_COMPILERRT_FUNCTION(__modsi3) 31*0b57cec5SDimitry Andric#if __ARM_ARCH_EXT_IDIV__ 32*0b57cec5SDimitry Andric tst r1, r1 33*0b57cec5SDimitry Andric beq LOCAL_LABEL(divzero) 34*0b57cec5SDimitry Andric sdiv r2, r0, r1 35*0b57cec5SDimitry Andric mls r0, r2, r1, r0 36*0b57cec5SDimitry Andric bx lr 37*0b57cec5SDimitry AndricLOCAL_LABEL(divzero): 38*0b57cec5SDimitry Andric mov r0, #0 39*0b57cec5SDimitry Andric bx lr 40*0b57cec5SDimitry Andric#else 41*0b57cec5SDimitry Andric ESTABLISH_FRAME 42*0b57cec5SDimitry Andric // Set aside the sign of the dividend. 43*0b57cec5SDimitry Andric mov r4, r0 44*0b57cec5SDimitry Andric // Take absolute value of a and b via abs(x) = (x^(x >> 31)) - (x >> 31). 45*0b57cec5SDimitry Andric eor r2, r0, r0, asr #31 46*0b57cec5SDimitry Andric eor r3, r1, r1, asr #31 47*0b57cec5SDimitry Andric sub r0, r2, r0, asr #31 48*0b57cec5SDimitry Andric sub r1, r3, r1, asr #31 49*0b57cec5SDimitry Andric // abs(a) % abs(b) 50*0b57cec5SDimitry Andric bl SYMBOL_NAME(__umodsi3) 51*0b57cec5SDimitry Andric // Apply sign of dividend to result and return. 52*0b57cec5SDimitry Andric eor r0, r0, r4, asr #31 53*0b57cec5SDimitry Andric sub r0, r0, r4, asr #31 54*0b57cec5SDimitry Andric CLEAR_FRAME_AND_RETURN 55*0b57cec5SDimitry Andric#endif 56*0b57cec5SDimitry AndricEND_COMPILERRT_FUNCTION(__modsi3) 57*0b57cec5SDimitry Andric 58*0b57cec5SDimitry AndricNO_EXEC_STACK_DIRECTIVE 59*0b57cec5SDimitry Andric 60