regs.c revision 929bd57ca202fd2f2e8485ebf65d683e664f67b5 
1/*
2 * This file is part of ltrace.
3 * Copyright (C) 2011,2012 Petr Machata, Red Hat Inc.
4 * Copyright (C) 2008,2009 Juan Cespedes
5 * Copyright (C) 2006 Ian Wienand
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation; either version 2 of the
10 * License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 */
22
23#include "config.h"
24
25#include <sys/types.h>
26#include <sys/ptrace.h>
27#include <errno.h>
28
29#include <asm/ptrace_offsets.h>
30#include <asm/rse.h>
31
32#include <stddef.h>
33#include "proc.h"
34#include "common.h"
35
36void *
37get_instruction_pointer(struct process *proc)
38{
39	unsigned long ip = ptrace(PTRACE_PEEKUSER, proc->pid, PT_CR_IIP, 0);
40	unsigned long slot =
41	    (ptrace(PTRACE_PEEKUSER, proc->pid, PT_CR_IPSR, 0) >> 41) & 3;
42
43	return (void *)(ip | slot);
44}
45
46void
47set_instruction_pointer(struct process *proc, void *addr)
48{
49
50	unsigned long newip = (unsigned long)addr;
51	unsigned long slot = (unsigned long)addr & 0xf;
52	unsigned long psr = ptrace(PTRACE_PEEKUSER, proc->pid, PT_CR_IPSR, 0);
53
54	psr &= ~(3UL << 41);
55	psr |= (slot & 0x3) << 41;
56
57	newip &= ~0xfUL;
58
59	ptrace(PTRACE_POKEUSER, proc->pid, PT_CR_IIP, (long)newip);
60	ptrace(PTRACE_POKEUSER, proc->pid, PT_CR_IPSR, psr);
61}
62
63void *
64get_stack_pointer(struct process *proc)
65{
66	long l = ptrace(PTRACE_PEEKUSER, proc->pid, PT_R12, 0);
67	if (l == -1 && errno)
68		return NULL;
69	return (void *)l;
70}
71
72void *
73get_return_addr(struct process *proc, void *stack_pointer)
74{
75	long l = ptrace(PTRACE_PEEKUSER, proc->pid, PT_B0, 0);
76	if (l == -1 && errno)
77		return NULL;
78	return (void *)l;
79}
80
81void
82set_return_addr(struct process *proc, void *addr)
83{
84	ptrace(PTRACE_POKEUSER, proc->pid, PT_B0, addr);
85}
86