1/* 2 * Copyright (C) 2012 Andrew Turner 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 */ 27 28#include <machine/asm.h> 29/* 30 * These calculate: 31 * q = n / m 32 * With a remainer r. 33 * 34 * They take n in {r0, r1} and m in {r2, r3} then pass them into the 35 * helper function. The hepler functions return q in {r0, r1} as 36 * required by the API spec however r is returned on the stack. The 37 * ABI required us to return r in {r2, r3}. 38 * 39 * We need to allocate 8 bytes on the stack to store r, the link 40 * register, and a pointer to the space where the helper function 41 * will write r to. After returning from the helper fuinction we load 42 * the old link register and r from the stack and return. 43 */ 44ENTRY_NP(__aeabi_ldivmod) 45 sub sp, sp, #8 /* Space for the remainder */ 46 stmfd sp!, {sp, lr} /* Save a pointer to the above space and lr */ 47 bl PIC_SYM(_C_LABEL(__kern_ldivmod), PLT) 48 ldr lr, [sp, #4] /* Restore lr */ 49 add sp, sp, #8 /* Move sp to the remainder value */ 50 ldmfd sp!, {r2, r3} /* Load the remainder */ 51 RET 52END(__aeabi_ldivmod) 53 54ENTRY_NP(__aeabi_uldivmod) 55 sub sp, sp, #8 /* Space for the remainder */ 56 stmfd sp!, {sp, lr} /* Save a pointer to the above space and lr */ 57 bl PIC_SYM(_C_LABEL(__qdivrem), PLT) 58 ldr lr, [sp, #4] /* Restore lr */ 59 add sp, sp, #8 /* Move sp to the remainder value */ 60 ldmfd sp!, {r2, r3} /* Load the remainder */ 61 RET 62END(__aeabi_uldivmod) 63