1 /* DWARF2 EH unwinding support for DragonFly BSD: AMD x86-64 and x86.
2 Copyright (C) 2010 John Marino <draco@marino.st> */
3
4 /* Do code reading to identify a signal frame, and set the frame
5 state data appropriately. See unwind-dw2.c for the structs. */
6
7 #include <sys/types.h>
8 #include <sys/sysctl.h>
9 #include <signal.h>
10 #include <sys/ucontext.h>
11 #include <machine/sigframe.h>
12
13
14 #define REG_NAME(reg) sf_uc.uc_mcontext.mc_## reg
15
16 #ifdef __x86_64__
17 #define MD_FALLBACK_FRAME_STATE_FOR x86_64_dragonfly_fallback_frame_state
18
19
20 static void
x86_64_sigtramp_range(unsigned char ** start,unsigned char ** end)21 x86_64_sigtramp_range (unsigned char **start, unsigned char **end)
22 {
23 unsigned long ps_strings;
24 int mib[2];
25 size_t len;
26
27 mib[0] = CTL_KERN;
28 mib[1] = KERN_PS_STRINGS;
29 len = sizeof (ps_strings);
30 sysctl (mib, 2, &ps_strings, &len, NULL, 0);
31
32 *start = (unsigned char *)ps_strings - 32;
33 *end = (unsigned char *)ps_strings;
34 }
35
36
37 static _Unwind_Reason_Code
x86_64_dragonfly_fallback_frame_state(struct _Unwind_Context * context,_Unwind_FrameState * fs)38 x86_64_dragonfly_fallback_frame_state
39 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
40 {
41 unsigned char *pc = context->ra;
42 unsigned char *sigtramp_start, *sigtramp_end;
43 struct sigframe *sf;
44 long new_cfa;
45
46 x86_64_sigtramp_range(&sigtramp_start, &sigtramp_end);
47 if (pc >= sigtramp_end || pc < sigtramp_start)
48 return _URC_END_OF_STACK;
49
50 sf = (struct sigframe *) context->cfa;
51 new_cfa = sf->REG_NAME(rsp);
52 fs->regs.cfa_how = CFA_REG_OFFSET;
53 /* Register 7 is rsp */
54 fs->regs.cfa_reg = 7;
55 fs->regs.cfa_offset = new_cfa - (long) context->cfa;
56
57 /* The SVR4 register numbering macros aren't usable in libgcc. */
58 fs->regs.reg[0].how = REG_SAVED_OFFSET;
59 fs->regs.reg[0].loc.offset = (long)&sf->REG_NAME(rax) - new_cfa;
60 fs->regs.reg[1].how = REG_SAVED_OFFSET;
61 fs->regs.reg[1].loc.offset = (long)&sf->REG_NAME(rdx) - new_cfa;
62 fs->regs.reg[2].how = REG_SAVED_OFFSET;
63 fs->regs.reg[2].loc.offset = (long)&sf->REG_NAME(rcx) - new_cfa;
64 fs->regs.reg[3].how = REG_SAVED_OFFSET;
65 fs->regs.reg[3].loc.offset = (long)&sf->REG_NAME(rbx) - new_cfa;
66 fs->regs.reg[4].how = REG_SAVED_OFFSET;
67 fs->regs.reg[4].loc.offset = (long)&sf->REG_NAME(rsi) - new_cfa;
68 fs->regs.reg[5].how = REG_SAVED_OFFSET;
69 fs->regs.reg[5].loc.offset = (long)&sf->REG_NAME(rdi) - new_cfa;
70 fs->regs.reg[6].how = REG_SAVED_OFFSET;
71 fs->regs.reg[6].loc.offset = (long)&sf->REG_NAME(rbp) - new_cfa;
72 fs->regs.reg[8].how = REG_SAVED_OFFSET;
73 fs->regs.reg[8].loc.offset = (long)&sf->REG_NAME(r8) - new_cfa;
74 fs->regs.reg[9].how = REG_SAVED_OFFSET;
75 fs->regs.reg[9].loc.offset = (long)&sf->REG_NAME(r9) - new_cfa;
76 fs->regs.reg[10].how = REG_SAVED_OFFSET;
77 fs->regs.reg[10].loc.offset = (long)&sf->REG_NAME(r10) - new_cfa;
78 fs->regs.reg[11].how = REG_SAVED_OFFSET;
79 fs->regs.reg[11].loc.offset = (long)&sf->REG_NAME(r11) - new_cfa;
80 fs->regs.reg[12].how = REG_SAVED_OFFSET;
81 fs->regs.reg[12].loc.offset = (long)&sf->REG_NAME(r12) - new_cfa;
82 fs->regs.reg[13].how = REG_SAVED_OFFSET;
83 fs->regs.reg[13].loc.offset = (long)&sf->REG_NAME(r13) - new_cfa;
84 fs->regs.reg[14].how = REG_SAVED_OFFSET;
85 fs->regs.reg[14].loc.offset = (long)&sf->REG_NAME(r14) - new_cfa;
86 fs->regs.reg[15].how = REG_SAVED_OFFSET;
87 fs->regs.reg[15].loc.offset = (long)&sf->REG_NAME(r15) - new_cfa;
88 fs->regs.reg[16].how = REG_SAVED_OFFSET;
89 fs->regs.reg[16].loc.offset = (long)&sf->REG_NAME(rip) - new_cfa;
90 fs->retaddr_column = 16;
91 fs->signal_frame = 1;
92 return _URC_NO_REASON;
93 }
94
95 #else /* Next section is for i386 */
96
97 #define MD_FALLBACK_FRAME_STATE_FOR x86_dragonfly_fallback_frame_state
98
99
100 static void
x86_sigtramp_range(unsigned char ** start,unsigned char ** end)101 x86_sigtramp_range (unsigned char **start, unsigned char **end)
102 {
103 unsigned long ps_strings;
104 int mib[2];
105 size_t len;
106
107 mib[0] = CTL_KERN;
108 mib[1] = KERN_PS_STRINGS;
109 len = sizeof (ps_strings);
110 sysctl (mib, 2, &ps_strings, &len, NULL, 0);
111
112 *start = (unsigned char *)ps_strings - 128;
113 *end = (unsigned char *)ps_strings;
114 }
115
116
117 static _Unwind_Reason_Code
x86_dragonfly_fallback_frame_state(struct _Unwind_Context * context,_Unwind_FrameState * fs)118 x86_dragonfly_fallback_frame_state
119 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
120 {
121 unsigned char *pc = context->ra;
122 unsigned char *sigtramp_start, *sigtramp_end;
123 struct sigframe *sf;
124 long new_cfa;
125
126 x86_sigtramp_range(&sigtramp_start, &sigtramp_end);
127
128 if (pc >= sigtramp_end || pc < sigtramp_start)
129 return _URC_END_OF_STACK;
130
131 sf = (struct sigframe *) context->cfa;
132 new_cfa = sf->REG_NAME(esp);
133 fs->regs.cfa_how = CFA_REG_OFFSET;
134 fs->regs.cfa_reg = 4;
135 fs->regs.cfa_offset = new_cfa - (long) context->cfa;
136
137 /* The SVR4 register numbering macros aren't usable in libgcc. */
138 fs->regs.reg[0].how = REG_SAVED_OFFSET;
139 fs->regs.reg[0].loc.offset = (long)&sf->REG_NAME(eax) - new_cfa;
140 fs->regs.reg[3].how = REG_SAVED_OFFSET;
141 fs->regs.reg[3].loc.offset = (long)&sf->REG_NAME(ebx) - new_cfa;
142 fs->regs.reg[1].how = REG_SAVED_OFFSET;
143 fs->regs.reg[1].loc.offset = (long)&sf->REG_NAME(ecx) - new_cfa;
144 fs->regs.reg[2].how = REG_SAVED_OFFSET;
145 fs->regs.reg[2].loc.offset = (long)&sf->REG_NAME(edx) - new_cfa;
146 fs->regs.reg[6].how = REG_SAVED_OFFSET;
147 fs->regs.reg[6].loc.offset = (long)&sf->REG_NAME(esi) - new_cfa;
148 fs->regs.reg[7].how = REG_SAVED_OFFSET;
149 fs->regs.reg[7].loc.offset = (long)&sf->REG_NAME(edi) - new_cfa;
150 fs->regs.reg[5].how = REG_SAVED_OFFSET;
151 fs->regs.reg[5].loc.offset = (long)&sf->REG_NAME(ebp) - new_cfa;
152 fs->regs.reg[8].how = REG_SAVED_OFFSET;
153 fs->regs.reg[8].loc.offset = (long)&sf->REG_NAME(eip) - new_cfa;
154 fs->retaddr_column = 8;
155 fs->signal_frame = 1;
156 return _URC_NO_REASON;
157 }
158 #endif /* ifdef __x86_64__ */
159