rtld_start.S revision 1.9.44.1 1 /* $NetBSD: rtld_start.S,v 1.9.44.1 2009/08/26 03:32:53 matt Exp $ */
2
3 /*
4 * Copyright 1997 Michael L. Hitch <mhitch (at) montana.edu>
5 * Portions copyright 2002 Charles M. Hannum <root (at) ihack.net>
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include <mips/asm.h>
32
33 .globl _C_LABEL(_rtld_relocate_nonplt_self)
34 .globl _C_LABEL(_rtld)
35
36 LEAF(rtld_start)
37 .set noreorder
38 SETUP_GP
39 PTR_SUBU sp, 2*SZREG # adjust stack pointer
40 SETUP_GP64(s4, rtld_start)
41 SAVE_GP(s4)
42 # -> 0*SZREG(sp) for atexit
43 # -> 1*SZREG(sp) for obj_main
44 move s0, a0 # save stack pointer from a0
45 move s3, a3 # save ps_strings pointer
46
47 PTR_LA a1, 1f
48 bal 1f
49 PTR_LA t9, _C_LABEL(_rtld_relocate_nonplt_self)
50 1: PTR_SUBU a1, ra, a1 # relocbase
51 move s2,a1
52 PTR_LA a0,_DYNAMIC
53 PTR_ADDU t9, a1, t9
54 jalr t9 # _rtld_relocate_nonplt_self(dynp, relocabase)
55 PTR_ADDU a0, a1, a0 # &_DYNAMIC
56
57 move a1, s2 # relocbase
58 move a0, sp # sp
59 jal _C_LABEL(_rtld) # v0 = _rtld(sp, relocbase)
60 nop
61
62 PTR_L a1, 0*SZREG(sp) # our atexit function
63 PTR_L a2, 1*SZREG(sp) # obj_main entry
64 PTR_ADDU sp, 3*SZREG # readjust stack
65 move a0, s0 # stack pointer
66 move t9, v0
67 jr t9 # _start(sp, cleanup, obj);
68 move a3, s3 # restore ps_strings
69
70 END(rtld_start)
71
72 #define XCALLFRAME_SIZ (11*SZREG)
73 #define XCALLFRAME_RA (10*SZREG)
74 #define XCALLFRAME_GP (9*SZREG)
75 #define XCALLFRAME_S0 (8*SZREG)
76 #define XCALLFRAME_A3 (7*SZREG)
77 #define XCALLFRAME_A2 (6*SZREG)
78 #define XCALLFRAME_A1 (5*SZREG)
79 #define XCALLFRAME_A0 (4*SZREG)
80 #if defined(__mips_n32) || defined(__mips_n64)
81 #define XCALLFRAME_A7 (3*SZREG)
82 #define XCALLFRAME_A6 (2*SZREG)
83 #define XCALLFRAME_A5 (1*SZREG)
84 #define XCALLFRAME_A4 (0*SZREG)
85 #endif
86
87 .globl _rtld_bind_start
88 .ent _rtld_bind_start
89 _rtld_bind_start:
90 #if defined(__mips_o32) || defined(__mips_o64)
91 move v1, gp # save old GP
92 PTR_ADDU t9, 8 # modify T9 to point at .cpload
93 #endif
94 SETUP_GP
95 PTR_SUBU sp, XCALLFRAME_SIZ # save arguments and sp value in stack
96 SETUP_GP64(XCALLFRAME_GP, _rtld_bind_start)
97 SAVE_GP(XCALLFRAME_GP)
98 #if defined(__mips_n32) || defined(__mips_n64)
99 REG_S a4, XCALLFRAME_A4(sp)
100 REG_S a5, XCALLFRAME_A5(sp)
101 REG_S a6, XCALLFRAME_A6(sp)
102 REG_S a7, XCALLFRAME_A7(sp)
103 #endif
104 REG_S a0, XCALLFRAME_A0(sp)
105 REG_S a1, XCALLFRAME_A1(sp)
106 REG_S a2, XCALLFRAME_A2(sp)
107 REG_S a3, XCALLFRAME_A3(sp)
108 REG_S $15, XCALLFRAME_RA(sp) # ra is in t7/t3
109 REG_S s0, XCALLFRAME_SP(sp)
110 move s0, sp
111 move a0, t8 # symbol index
112 move a1, $15 # old RA
113 move a2, v1 # old GP
114 move a3, ra # current RA
115 jal _C_LABEL(_rtld_bind)
116 nop
117 move sp, s0
118 REG_L ra, XCALLFRAME_RA(sp)
119 REG_L s0, XCALLFRAME_S0(sp)
120 REG_L a0, XCALLFRAME_A0(sp)
121 REG_L a1, XCALLFRAME_A1(sp)
122 REG_L a2, XCALLFRAME_A2(sp)
123 REG_L a3, XCALLFRAME_A3(sp)
124 #if defined(__mips_n32) || defined(__mips_n64)
125 REG_L a4, XCALLFRAME_A4(sp)
126 REG_L a5, XCALLFRAME_A5(sp)
127 REG_L a6, XCALLFRAME_A6(sp)
128 REG_L a7, XCALLFRAME_A7(sp)
129 #endif
130 RESTORE_GP64
131 PTR_ADDU sp, XCALLFRAME_SIZ
132 move t9, v0
133 jr t9
134 nop
135 END(_rtld_bind_start)
136