1/* $NetBSD: udivsi3.S,v 1.10 2011/07/14 09:48:04 mrg Exp $ */ 2 3/*- 4 * Copyright (c) 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * William Jolitz. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: @(#)udivsi3.s 5.1 (Berkeley) 5/15/90 35 */ 36 37#include <machine/asm.h> 38#if defined(LIBC_SCCS) 39 RCSID("$NetBSD: udivsi3.S,v 1.10 2011/07/14 09:48:04 mrg Exp $") 40#endif 41 42/* 43 * IMPOTANT: This function is special. 44 * 45 * This function is an auxiliary "millicode" function that is 46 * referenced by the code generated by gcc for unsigned integer 47 * division. But gcc does NOT treat a call to this function as an 48 * ordinary function call - it can clobber only R4. 49 * 50 * See the definition of "udivsi3_i1" in gcc/config/sh/sh.md 51 * 52 * As the consequence this function cannot be called via any 53 * indirection that assumes normal calling convention: 54 * 55 * . cannot have _PROF_PROLOGUE 56 * . cannot be called via PLT (not relevant for kernel) 57 */ 58 59 60#ifdef __ELF__ 61 .hidden __udivsi3 62#endif 63 64 65/* r0 <= r4 / r5 */ 66NENTRY(__udivsi3) 67 tst r5, r5 68 bt .L_div_by_zero 69 70 mov #0, r0 71 div0u 72#define DIVSTEP rotcl r4; div1 r5, r0 73 /* repeat 32 times */ 74 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 75 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 76 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 77 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 78#undef DIVSTEP 79 rotcl r4 80 81 rts 82 mov r4, r0 83 84.L_div_by_zero: 85 rts 86 mov #0, r0 87