diff options
Diffstat (limited to 'sys/lib/libkern/arch/sh/udivsi3.S')
| -rw-r--r-- | sys/lib/libkern/arch/sh/udivsi3.S | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/sys/lib/libkern/arch/sh/udivsi3.S b/sys/lib/libkern/arch/sh/udivsi3.S new file mode 100644 index 00000000000..0483d74337f --- /dev/null +++ b/sys/lib/libkern/arch/sh/udivsi3.S @@ -0,0 +1,107 @@ +/* $NetBSD: udivsi3.S,v 1.7 2006/05/22 20:56:44 uwe Exp $ */ + +/*- + * Copyright (c) 1990 The Regents of the University of California. + * All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * William Jolitz. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * from: @(#)udivsi3.s 5.1 (Berkeley) 5/15/90 + */ + +#include <machine/asm.h> + +/* + * IMPOTANT: This function is special. + * + * This function is an auxiliary function that is referenced by the + * code generated by gcc for integer division. But gcc does NOT treat + * a call to this function as an ordinary function call w.r.t. the set + * of register this call clobbers. See the definition of "udivsi3_i1" + * in gcc/config/sh/sh.md. + * + * Any call to this function MUST NOT clobber any registers besides r4 + * and r0, where the result is returned. At the time of the call the + * r4 contains the first argument, so we are only left with r0, and we + * cannot do anything meaningful using only one register. The + * consequences are: + * + * . this function cannot have _PROF_PROLOGUE + * . this function cannot be called via PLT + */ + + +/* r0 <= r4 / r5 */ +NENTRY(__udivsi3) + tst r5, r5 + bt div_by_zero + + mov #0, r0 + div0u +#define DIVSTEP rotcl r4; div1 r5, r0 + /* repeat 32 times */ + DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; + DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; + DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; + DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; DIVSTEP; +#undef DIVSTEP + rotcl r4 + + rts + mov r4, r0 + +div_by_zero: +#ifdef _KERNEL + rts + mov #0, r0 +#else + mov.l r14, @-r15 + sts.l pr, @-r15 + mov r15, r14 + + mov.l L_raise, r1 +#ifdef PIC +1: bsrf r1 +#else + jsr @r1 +#endif + mov #8, r4 /* delay slot. 8 <- SIGFPE. */ + mov #0, r0 + + lds.l @r15+, pr + rts + mov.l @r15+, r14 + + .align 2 +L_raise: +#ifdef PIC + .long _C_LABEL(raise)-(1b+4) +#else + .long _C_LABEL(raise) +#endif +#endif |