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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/lib/backtrace.S
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/lib/backtrace.S')
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1 files changed, 157 insertions, 0 deletions
diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S
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1/*
2 * linux/arch/arm/lib/backtrace.S
3 *
4 * Copyright (C) 1995, 1996 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * 27/03/03 Ian Molton Clean up CONFIG_CPU
11 *
12 */
13#include <linux/config.h>
14#include <linux/linkage.h>
15#include <asm/assembler.h>
16 .text
17
18@ fp is 0 or stack frame
19
20#define frame r4
21#define next r5
22#define save r6
23#define mask r7
24#define offset r8
25
26ENTRY(__backtrace)
27 mov r1, #0x10
28 mov r0, fp
29
30ENTRY(c_backtrace)
31
32#ifndef CONFIG_FRAME_POINTER
33 mov pc, lr
34#else
35
36 stmfd sp!, {r4 - r8, lr} @ Save an extra register so we have a location...
37 tst r1, #0x10 @ 26 or 32-bit?
38 moveq mask, #0xfc000003
39 movne mask, #0
40 tst mask, r0
41 movne r0, #0
42 movs frame, r0
431: moveq r0, #-2
44 LOADREGS(eqfd, sp!, {r4 - r8, pc})
45
462: stmfd sp!, {pc} @ calculate offset of PC in STMIA instruction
47 ldr r0, [sp], #4
48 adr r1, 2b - 4
49 sub offset, r0, r1
50
513: tst frame, mask @ Check for address exceptions...
52 bne 1b
53
541001: ldr next, [frame, #-12] @ get fp
551002: ldr r2, [frame, #-4] @ get lr
561003: ldr r3, [frame, #0] @ get pc
57 sub save, r3, offset @ Correct PC for prefetching
58 bic save, save, mask
591004: ldr r1, [save, #0] @ get instruction at function
60 mov r1, r1, lsr #10
61 ldr r3, .Ldsi+4
62 teq r1, r3
63 subeq save, save, #4
64 mov r0, save
65 bic r1, r2, mask
66 bl dump_backtrace_entry
67
68 ldr r0, [frame, #-8] @ get sp
69 sub r0, r0, #4
701005: ldr r1, [save, #4] @ get instruction at function+4
71 mov r3, r1, lsr #10
72 ldr r2, .Ldsi+4
73 teq r3, r2 @ Check for stmia sp!, {args}
74 addeq save, save, #4 @ next instruction
75 bleq .Ldumpstm
76
77 sub r0, frame, #16
781006: ldr r1, [save, #4] @ Get 'stmia sp!, {rlist, fp, ip, lr, pc}' instruction
79 mov r3, r1, lsr #10
80 ldr r2, .Ldsi
81 teq r3, r2
82 bleq .Ldumpstm
83
84 /*
85 * A zero next framepointer means we're done.
86 */
87 teq next, #0
88 LOADREGS(eqfd, sp!, {r4 - r8, pc})
89
90 /*
91 * The next framepointer must be above the
92 * current framepointer.
93 */
94 cmp next, frame
95 mov frame, next
96 bhi 3b
97 b 1007f
98
99/*
100 * Fixup for LDMDB
101 */
102 .section .fixup,"ax"
103 .align 0
1041007: ldr r0, =.Lbad
105 mov r1, frame
106 bl printk
107 LOADREGS(fd, sp!, {r4 - r8, pc})
108 .ltorg
109 .previous
110
111 .section __ex_table,"a"
112 .align 3
113 .long 1001b, 1007b
114 .long 1002b, 1007b
115 .long 1003b, 1007b
116 .long 1004b, 1007b
117 .long 1005b, 1007b
118 .long 1006b, 1007b
119 .previous
120
121#define instr r4
122#define reg r5
123#define stack r6
124
125.Ldumpstm: stmfd sp!, {instr, reg, stack, r7, lr}
126 mov stack, r0
127 mov instr, r1
128 mov reg, #9
129 mov r7, #0
1301: mov r3, #1
131 tst instr, r3, lsl reg
132 beq 2f
133 add r7, r7, #1
134 teq r7, #4
135 moveq r7, #0
136 moveq r3, #'\n'
137 movne r3, #' '
138 ldr r2, [stack], #-4
139 mov r1, reg
140 adr r0, .Lfp
141 bl printk
1422: subs reg, reg, #1
143 bpl 1b
144 teq r7, #0
145 adrne r0, .Lcr
146 blne printk
147 mov r0, stack
148 LOADREGS(fd, sp!, {instr, reg, stack, r7, pc})
149
150.Lfp: .asciz " r%d = %08X%c"
151.Lcr: .asciz "\n"
152.Lbad: .asciz "Backtrace aborted due to bad frame pointer <%p>\n"
153 .align
154.Ldsi: .word 0x00e92dd8 >> 2
155 .word 0x00e92d00 >> 2
156
157#endif