1/* $NetBSD: udivsi3.S,v 1.7 2006/05/22 20:56:44 uwe 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 39/* 40 * IMPORTANT: This function is special. 41 * 42 * This function is an auxiliary function that is referenced by the 43 * code generated by gcc for integer division. But gcc does NOT treat 44 * a call to this function as an ordinary function call w.r.t. the set 45 * of register this call clobbers. See the definition of "udivsi3_i1" 46 * in gcc/config/sh/sh.md. 47 * 48 * Any call to this function MUST NOT clobber any registers besides r4 49 * and r0, where the result is returned. At the time of the call the 50 * r4 contains the first argument, so we are only left with r0, and we 51 * cannot do anything meaningful using only one register. The 52 * consequences are: 53 * 54 * . this function cannot have _PROF_PROLOGUE 55 * . this function cannot be called via PLT 56 */ 57 58 59/* r0 <= r4 / r5 */ 60NENTRY(__udivsi3) 61 tst r5, r5 62 bt div_by_zero 63 64 mov #0, r0 65 div0u 66#define DIVSTEP rotcl r4; div1 r5, r0 67 /* repeat 32 times */ 68 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 69 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 70 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 71 DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; 72#undef DIVSTEP 73 rotcl r4 74 75 rts 76 mov r4, r0 77 78div_by_zero: 79#ifdef _KERNEL 80 rts 81 mov #0, r0 82#else 83 mov.l r14, @-r15 84 sts.l pr, @-r15 85 mov r15, r14 86 87 mov.l L_raise, r1 88#ifdef PIC 891: bsrf r1 90#else 91 jsr @r1 92#endif 93 mov #8, r4 /* delay slot. 8 <- SIGFPE. */ 94 mov #0, r0 95 96 lds.l @r15+, pr 97 rts 98 mov.l @r15+, r14 99 100 .align 2 101L_raise: 102#ifdef PIC 103 .long _C_LABEL(raise)-(1b+4) 104#else 105 .long _C_LABEL(raise) 106#endif 107#endif 108