1 /* $NetBSD: rtld_start.S,v 1.10 2009/12/14 00:41:19 matt Exp $ */
4 * Copyright 1997 Michael L. Hitch <mhitch@montana.edu>
5 * Portions copyright 2002 Charles M. Hannum <root@ihack.net>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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.
33 #include <machine/asm.h>
35 .globl _C_LABEL(_rtld_relocate_nonplt_self)
36 .globl _C_LABEL(_rtld)
38 #define PTR_SIZE (1<<PTR_SCALESHIFT)
42 * a1 rtld cleanup (filled in by dynamic loader)
43 * a2 rtld object (filled in by dynamic loader)
47 .frame sp, 4*PTR_SIZE, ra
48 .mask 0x10090000,-PTR_SIZE
51 PTR_SUBU sp, 4*PTR_SIZE /* adjust stack pointer */
52 SETUP_GP64(s4, rtld_start)
54 /* -> 1*PTR_SIZE(sp) for atexit */
55 /* -> 2*PTR_SIZE(sp) for obj_main */
56 move s0, a0 /* save stack pointer from a0 */
57 move s3, a3 /* save ps_strings pointer */
61 PTR_LA t0, _C_LABEL(_rtld_relocate_nonplt_self)
62 1: PTR_SUBU a1, ra, a1 /* relocbase */
65 jalr t9 /* _rtld_relocate_nonplt_self(dynp, relocabase) */
66 PTR_ADDU a0, a1, a0 /* &_DYNAMIC */
69 PTR_ADDU a1, sp, 2*PTR_SIZE /* &our atexit function */
70 PTR_ADDU a2, sp, 3*PTR_SIZE /* obj_main entry */
71 PTR_SUBU sp, 4*SZREG /* ABI requires to reserve memory for 4 regs */
72 PTR_LA t9, _C_LABEL(_rtld)
73 jalr t9 /* v0 = _rtld(sp, cleanup, objp) */
77 PTR_L a1, 2*PTR_SIZE(sp) /* our atexit function */
78 PTR_L a2, 3*PTR_SIZE(sp) /* obj_main entry */
79 PTR_ADDU sp, 4*PTR_SIZE /* readjust stack */
80 move a0, s0 /* stack pointer */
82 PTR_SUBU sp, 4*SZREG /* ABI requires to reserve memory for 4 regs */
83 move ra,t9 /* RA == PC signals backtrace routine to stop */
84 j t9 /* _start(sp, cleanup, obj); */
85 move a3, s3 /* restore ps_strings */
88 #define XCALLFRAME_SIZ (12*SZREG)
89 #define XCALLFRAME_RA (10*SZREG)
90 #define XCALLFRAME_GP (9*SZREG)
91 #define XCALLFRAME_S0 (8*SZREG)
92 #define XCALLFRAME_A3 (7*SZREG)
93 #define XCALLFRAME_A2 (6*SZREG)
94 #define XCALLFRAME_A1 (5*SZREG)
95 #define XCALLFRAME_A0 (4*SZREG)
96 #if defined(__mips_n32) || defined(__mips_n64)
97 #define XCALLFRAME_A7 (3*SZREG)
98 #define XCALLFRAME_A6 (2*SZREG)
99 #define XCALLFRAME_A5 (1*SZREG)
100 #define XCALLFRAME_A4 (0*SZREG)
103 .globl _rtld_bind_start
104 .ent _rtld_bind_start
106 .frame sp, XCALLFRAME_SIZ, $15
107 move v1, gp /* save old GP */
108 #if defined(__mips_o32) || defined(__mips_o64)
109 PTR_ADDU t9, 8 /* modify T9 to point at .cpload */
112 PTR_SUBU sp, XCALLFRAME_SIZ /* save arguments and sp value in stack */
113 SETUP_GP64(XCALLFRAME_GP, _rtld_bind_start)
114 SAVE_GP(XCALLFRAME_GP)
115 #if defined(__mips_n32) || defined(__mips_n64)
116 REG_S a4, XCALLFRAME_A4(sp)
117 REG_S a5, XCALLFRAME_A5(sp)
118 REG_S a6, XCALLFRAME_A6(sp)
119 REG_S a7, XCALLFRAME_A7(sp)
121 REG_S a0, XCALLFRAME_A0(sp)
122 REG_S a1, XCALLFRAME_A1(sp)
123 REG_S a2, XCALLFRAME_A2(sp)
124 REG_S a3, XCALLFRAME_A3(sp)
125 REG_S $15, XCALLFRAME_RA(sp) /* ra is in t7/t3 */
126 REG_S s0, XCALLFRAME_S0(sp)
129 move a0, v1 /* old GP */
130 PTR_SUBU a0, a0, 0x7ff0 /* The offset of $gp from the */
131 /* beginning of the .got section: */
132 /* $gp = .got + 0x7ff0, so */
133 /* .got = $gp - 0x7ff0 */
134 /* Simple math as you can see. */
135 #if defined(__mips_n64)
136 ld a0, 8(a0) /* object = pltgot[1] */
137 and a0, a0, 0x7fffffffffffffff
139 lw a0, 4(a0) /* object = pltgot[1] & 0x7fffffff */
140 and a0, a0, 0x7fffffff
142 move a1, t8 /* symbol index */
144 PTR_LA t9, _C_LABEL(_mips_rtld_bind)
149 REG_L ra, XCALLFRAME_RA(sp)
150 REG_L s0, XCALLFRAME_S0(sp)
151 REG_L a0, XCALLFRAME_A0(sp)
152 REG_L a1, XCALLFRAME_A1(sp)
153 REG_L a2, XCALLFRAME_A2(sp)
154 REG_L a3, XCALLFRAME_A3(sp)
155 #if defined(__mips_n32) || defined(__mips_n64)
156 REG_L a4, XCALLFRAME_A4(sp)
157 REG_L a5, XCALLFRAME_A5(sp)
158 REG_L a6, XCALLFRAME_A6(sp)
159 REG_L a7, XCALLFRAME_A7(sp)
162 PTR_ADDU sp, XCALLFRAME_SIZ
166 END(_rtld_bind_start)