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1 /*
2 * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009
3 * The President and Fellows of Harvard College.
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 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 /*
31 * setjmp and longjmp for MIPS.
32 */
33
34 #include <kern/mips/regdefs.h>
35
36 .text
37 .set noreorder
38
39 /*
40 * int setjmp(jmp_buf jb);
41 *
42 * Save the current state so we can return again from the call later
43 * if/when longjmp is called. (If the function that called setjmp
44 * returns before longjmp is called, the results are undefined. We
45 * only need to save registers, not the whole contents of the stack.)
46 */
47
48 .globl setjmp
49 .type setjmp,@function
50 .ent setjmp
51 setjmp:
52 /*
53 * jmp_buf is in a0. We need to save s0-s8, sp, and ra in it.
54 * Don't store more registers without adjusting machine/setjmp.h.
55 */
56
57 sw sp, 0(a0) /* save registers */
58 sw ra, 4(a0)
59 sw s0, 8(a0)
60 sw s1, 12(a0)
61 sw s2, 16(a0)
62 sw s3, 20(a0)
63 sw s4, 24(a0)
64 sw s5, 28(a0)
65 sw s6, 32(a0)
66 sw s7, 36(a0)
67 sw s8, 40(a0)
68
69 j ra /* done */
70 li v0, 0 /* return 0 (in delay slot) */
71 .end setjmp
72
73
74 /*
75 * void longjmp(jmp_buf jb, int code);
76 */
77 .globl longjmp
78 .type longjmp,@function
79 .ent longjmp
80 longjmp:
81 /*
82 * jmp_buf is in a0. Return code is in a1.
83 * We need to restore s0-s8, sp, and ra from the jmp_buf.
84 * The return code is forced to 1 if 0 is passed in.
85 */
86
87 sltiu t0, a1, 1 /* set t0 to 1 if return code is 0... otherwise 0 */
88 addu a1, a1, t0 /* update the return code */
89
90 lw sp, 0(a0) /* restore registers */
91 lw ra, 4(a0)
92 lw s0, 8(a0)
93 lw s1, 12(a0)
94 lw s2, 16(a0)
95 lw s3, 20(a0)
96 lw s4, 24(a0)
97 lw s5, 28(a0)
98 lw s6, 32(a0)
99 lw s7, 36(a0)
100 lw s8, 40(a0)
101
102 j ra /* return, to where setjmp was called from */
103 move v0, a1 /* set return value */
104 .end longjmp