1/*-
2 * Copyright (c) 2006 Marcel Moolenaar
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 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/proc.h>
33
34#include <machine/frame.h>
35#include <machine/md_var.h>
36
37#include <ia64/disasm/disasm.h>
38
39int
40ia64_emulate(struct trapframe *tf, struct thread *td)
41{
42	struct asm_bundle bundle;
43	struct asm_inst *i;
44	int slot;
45
46	if (!asm_decode(tf->tf_special.iip, &bundle))
47		return (SIGILL);
48
49	slot = ((tf->tf_special.psr & IA64_PSR_RI) == IA64_PSR_RI_0) ? 0 :
50	    ((tf->tf_special.psr & IA64_PSR_RI) == IA64_PSR_RI_1) ? 1 : 2;
51	if (slot == 1 && bundle.b_templ[slot] == 'L')
52		slot++;
53
54	i = bundle.b_inst + slot;
55	switch (i->i_op) {
56	case ASM_OP_BRL:
57		/*
58		 * We get the fault even if the predicate is false, so we
59		 * need to check the predicate first and simply advance to
60		 * the next bundle in that case.
61		 */
62		if (!(tf->tf_special.pr & (1UL << i->i_oper[0].o_value))) {
63			tf->tf_special.psr &= ~IA64_PSR_RI;
64			tf->tf_special.iip += 16;
65			return (0);
66		}
67		/*
68		 * The brl.cond is the simplest form. We only have to set
69		 * the IP to the address in the instruction and return.
70		 */
71		if (i->i_cmpltr[0].c_type == ASM_CT_COND) {
72			tf->tf_special.psr &= ~IA64_PSR_RI;
73			tf->tf_special.iip += i->i_oper[1].o_value;
74			return (0);
75		}
76		/* Sanity check... */
77		if (i->i_cmpltr[0].c_type != ASM_CT_CALL)
78			break;
79		/*
80		 * The brl.call is more difficult as we need to set-up the
81		 * call properly.
82		 */
83		break;
84	default:
85		break;
86	}
87
88	return (SIGILL);
89}
90