aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/include/asm/branch.h
blob: e28a3e0eb3cb6407b4ad6d6ac649e20a876ab69d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1996, 1997, 1998, 2001 by Ralf Baechle
 */
#ifndef _ASM_BRANCH_H
#define _ASM_BRANCH_H

#include <asm/ptrace.h>
#include <asm/inst.h>

extern int __isa_exception_epc(struct pt_regs *regs);
extern int __compute_return_epc(struct pt_regs *regs);
extern int __compute_return_epc_for_insn(struct pt_regs *regs,
					 union mips_instruction insn);
extern int __microMIPS_compute_return_epc(struct pt_regs *regs);
extern int __MIPS16e_compute_return_epc(struct pt_regs *regs);


static inline int delay_slot(struct pt_regs *regs)
{
	return regs->cp0_cause & CAUSEF_BD;
}

static inline unsigned long exception_epc(struct pt_regs *regs)
{
	if (likely(!delay_slot(regs)))
		return regs->cp0_epc;

	if (get_isa16_mode(regs->cp0_epc))
		return __isa_exception_epc(regs);

	return regs->cp0_epc + 4;
}

#define BRANCH_LIKELY_TAKEN 0x0001

static inline int compute_return_epc(struct pt_regs *regs)
{
	if (get_isa16_mode(regs->cp0_epc)) {
		if (cpu_has_mmips)
			return __microMIPS_compute_return_epc(regs);
		if (cpu_has_mips16)
			return __MIPS16e_compute_return_epc(regs);
		return regs->cp0_epc;
	}

	if (!delay_slot(regs)) {
		regs->cp0_epc += 4;
		return 0;
	}

	return __compute_return_epc(regs);
}

static inline int MIPS16e_compute_return_epc(struct pt_regs *regs,
					     union mips16e_instruction *inst)
{
	if (likely(!delay_slot(regs))) {
		if (inst->ri.opcode == MIPS16e_extend_op) {
			regs->cp0_epc += 4;
			return 0;
		}
		regs->cp0_epc += 2;
		return 0;
	}

	return __MIPS16e_compute_return_epc(regs);
}

#endif /* _ASM_BRANCH_H */