1/*
2Copyright (c) 2009 Nick Clifton <nickc@redhat.com>
3 */
4# setjmp/longjmp for Renesas RX.
5#
6# The jmpbuf looks like this:
7#
8# Register	jmpbuf offset
9# R0		0x0
10# R1		0x4
11# R2		0x8
12# R3		0xc
13# R4		0x10
14# R5		0x14
15# R6		0x18
16# R7		0x1c
17# R8		0x20
18# R9		0x24
19# R10		0x28
20# R11		0x2c
21# R12		0x30
22# R13		0x34
23# R14		0x38
24# R15		0x3c
25# PC		0x40
26#
27# R1 contains the pointer to jmpbuf:
28#
29#	int R1 = setjmp (jmp_buf R1)
30#	void longjmp (jmp_buf R1, int R2)
31#
32# The ABI allows for R1-R5 to be clobbered by functions.  We must be
33# careful to always leave the stack in a usable state in case an
34# interrupt happens.
35
36	.text
37	.global	_setjmp
38	.type	_setjmp, @function
39_setjmp:
40	mov.l	r0, [r1]	; save all the general registers
41	mov.l	r1, 0x4[r1]	; longjmp won't use this, but someone else might.
42	mov.l	r2, 0x8[r1]
43	mov.l	r3, 0xc[r1]
44	mov.l	r4, 0x10[r1]
45	mov.l	r5, 0x14[r1]
46	mov.l	r6, 0x18[r1]
47	mov.l	r7, 0x1c[r1]
48	mov.l	r8, 0x20[r1]
49	mov.l	r9, 0x24[r1]
50	mov.l	r10, 0x28[r1]
51	mov.l	r11, 0x2c[r1]
52	mov.l	r12, 0x30[r1]
53	mov.l	r13, 0x34[r1]
54	mov.l	r14, 0x38[r1]
55	mov.l	r15, 0x3c[r1]
56	mov.l	[r0], r2	; get return address off the stack
57	mov.l	r2, 0x40[r1]	; PC
58	mov	#0, r1		; Return 0.
59	rts
60.Lend1:
61	.size	_setjmp, .Lend1 - _setjmp
62
63
64	.global	_longjmp
65	.type	_longjmp, @function
66_longjmp:
67	tst	r2, r2		; Set the Z flag if r2 is 0.
68	stz	#1, r2		; If the Z flag was set put 1 into the return register.
69	mov	r2, 4[r1]	; Put r2 (our return value) into the setjmp buffer as r1.
70
71	mov.l	[r1], r0	; Restore the stack - there's a slot for PC
72	mov.l	0x40[r1], r2	; Get the saved PC
73	mov.l	r2, [r0]	; Overwrite the old return address
74
75	mov.l	0x3c[r1], r15
76	mov.l	0x38[r1], r14
77	mov.l	0x34[r1], r13
78	mov.l	0x30[r1], r12
79	mov.l	0x2c[r1], r11
80	mov.l	0x28[r1], r10
81	mov.l	0x24[r1], r9
82	mov.l	0x20[r1], r8
83	mov.l	0x1c[r1], r7
84	mov.l	0x18[r1], r6
85	mov.l	0x14[r1], r5
86	mov.l	0x10[r1], r4
87	mov.l	0xc[r1], r3
88	mov.l	0x8[r1], r2
89	mov.l	0x4[r1], r1	; This sets up the new return value
90	rts
91.Lend2:
92	.size	_longjmp, .Lend2 - _longjmp
93