1 /* DWARF2 EH unwinding support for Blackfin.
2 Copyright (C) 2007-2023 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
10
11 GCC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 Under Section 7 of GPL version 3, you are granted additional
17 permissions described in the GCC Runtime Library Exception, version
18 3.1, as published by the Free Software Foundation.
19
20 You should have received a copy of the GNU General Public License and
21 a copy of the GCC Runtime Library Exception along with this program;
22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 <http://www.gnu.org/licenses/>. */
24
25 /* Do code reading to identify a signal frame, and set the frame
26 state data appropriately. See unwind-dw2.c for the structs.
27 Don't use this at all if inhibit_libc is used. */
28
29 #ifndef inhibit_libc
30
31 #include <signal.h>
32 #include <sys/ucontext.h>
33
34 #define MD_FALLBACK_FRAME_STATE_FOR bfin_fallback_frame_state
35
36 static _Unwind_Reason_Code
37 bfin_fallback_frame_state (struct _Unwind_Context *context,
38 _Unwind_FrameState *fs)
39 {
40 unsigned char *pc = context->ra;
41 struct sigcontext *sc;
42 long new_cfa;
43
44 /* P0=__NR_rt_sigreturn (X); EXCPT 0x0; */
45 if (*(unsigned short *)pc == 0xe128
46 && *(unsigned short *)(pc + 2) == 0x00ad
47 && *(unsigned short *)(pc + 4) == 0x00a0)
48 {
49 struct rt_sigframe {
50 int sig;
51 siginfo_t *pinfo;
52 void *puc;
53 char retcode[8];
54 siginfo_t info;
55 ucontext_t uc;
56 } *rt_ = context->cfa;
57
58 /* The void * cast is necessary to avoid an aliasing warning.
59 The aliasing warning is correct, but should not be a problem
60 because it does not alias anything. */
61 sc = (struct sigcontext *)(void *)&rt_->uc.uc_mcontext.gregs;
62 }
63 else
64 return _URC_END_OF_STACK;
65
66 new_cfa = sc->sc_usp;
67 fs->regs.cfa_how = CFA_REG_OFFSET;
68 fs->regs.cfa_reg = 14;
69 fs->regs.cfa_offset = new_cfa - (long) context->cfa;
70
71 fs->regs.how[0] = REG_SAVED_OFFSET;
72 fs->regs.reg[0].loc.offset = (long)&sc->sc_r0 - new_cfa;
73 fs->regs.how[1] = REG_SAVED_OFFSET;
74 fs->regs.reg[1].loc.offset = (long)&sc->sc_r1 - new_cfa;
75 fs->regs.how[2] = REG_SAVED_OFFSET;
76 fs->regs.reg[2].loc.offset = (long)&sc->sc_r2 - new_cfa;
77 fs->regs.how[3] = REG_SAVED_OFFSET;
78 fs->regs.reg[3].loc.offset = (long)&sc->sc_r3 - new_cfa;
79 fs->regs.how[4] = REG_SAVED_OFFSET;
80 fs->regs.reg[4].loc.offset = (long)&sc->sc_r4 - new_cfa;
81 fs->regs.how[5] = REG_SAVED_OFFSET;
82 fs->regs.reg[5].loc.offset = (long)&sc->sc_r5 - new_cfa;
83 fs->regs.how[6] = REG_SAVED_OFFSET;
84 fs->regs.reg[6].loc.offset = (long)&sc->sc_r6 - new_cfa;
85 fs->regs.how[7] = REG_SAVED_OFFSET;
86 fs->regs.reg[7].loc.offset = (long)&sc->sc_r7 - new_cfa;
87 fs->regs.how[8] = REG_SAVED_OFFSET;
88 fs->regs.reg[8].loc.offset = (long)&sc->sc_p0 - new_cfa;
89 fs->regs.how[9] = REG_SAVED_OFFSET;
90 fs->regs.reg[9].loc.offset = (long)&sc->sc_p1 - new_cfa;
91 fs->regs.how[10] = REG_SAVED_OFFSET;
92 fs->regs.reg[10].loc.offset = (long)&sc->sc_p2 - new_cfa;
93 fs->regs.how[11] = REG_SAVED_OFFSET;
94 fs->regs.reg[11].loc.offset = (long)&sc->sc_p3 - new_cfa;
95 fs->regs.how[12] = REG_SAVED_OFFSET;
96 fs->regs.reg[12].loc.offset = (long)&sc->sc_p4 - new_cfa;
97 fs->regs.how[13] = REG_SAVED_OFFSET;
98 fs->regs.reg[13].loc.offset = (long)&sc->sc_p5 - new_cfa;
99
100 fs->regs.how[15] = REG_SAVED_OFFSET;
101 fs->regs.reg[15].loc.offset = (long)&sc->sc_fp - new_cfa;
102 fs->regs.how[16] = REG_SAVED_OFFSET;
103 fs->regs.reg[16].loc.offset = (long)&sc->sc_i0 - new_cfa;
104 fs->regs.how[17] = REG_SAVED_OFFSET;
105 fs->regs.reg[17].loc.offset = (long)&sc->sc_i1 - new_cfa;
106 fs->regs.how[18] = REG_SAVED_OFFSET;
107 fs->regs.reg[18].loc.offset = (long)&sc->sc_i2 - new_cfa;
108 fs->regs.how[19] = REG_SAVED_OFFSET;
109 fs->regs.reg[19].loc.offset = (long)&sc->sc_i3 - new_cfa;
110 fs->regs.how[20] = REG_SAVED_OFFSET;
111 fs->regs.reg[20].loc.offset = (long)&sc->sc_b0 - new_cfa;
112 fs->regs.how[21] = REG_SAVED_OFFSET;
113 fs->regs.reg[21].loc.offset = (long)&sc->sc_b1 - new_cfa;
114 fs->regs.how[22] = REG_SAVED_OFFSET;
115 fs->regs.reg[22].loc.offset = (long)&sc->sc_b2 - new_cfa;
116 fs->regs.how[23] = REG_SAVED_OFFSET;
117 fs->regs.reg[23].loc.offset = (long)&sc->sc_b3 - new_cfa;
118 fs->regs.how[24] = REG_SAVED_OFFSET;
119 fs->regs.reg[24].loc.offset = (long)&sc->sc_l0 - new_cfa;
120 fs->regs.how[25] = REG_SAVED_OFFSET;
121 fs->regs.reg[25].loc.offset = (long)&sc->sc_l1 - new_cfa;
122 fs->regs.how[26] = REG_SAVED_OFFSET;
123 fs->regs.reg[26].loc.offset = (long)&sc->sc_l2 - new_cfa;
124 fs->regs.how[27] = REG_SAVED_OFFSET;
125 fs->regs.reg[27].loc.offset = (long)&sc->sc_l3 - new_cfa;
126 fs->regs.how[28] = REG_SAVED_OFFSET;
127 fs->regs.reg[28].loc.offset = (long)&sc->sc_m0 - new_cfa;
128 fs->regs.how[29] = REG_SAVED_OFFSET;
129 fs->regs.reg[29].loc.offset = (long)&sc->sc_m1 - new_cfa;
130 fs->regs.how[30] = REG_SAVED_OFFSET;
131 fs->regs.reg[30].loc.offset = (long)&sc->sc_m2 - new_cfa;
132 fs->regs.how[31] = REG_SAVED_OFFSET;
133 fs->regs.reg[31].loc.offset = (long)&sc->sc_m3 - new_cfa;
134 /* FIXME: Handle A0, A1, CC. */
135 fs->regs.how[35] = REG_SAVED_OFFSET;
136 fs->regs.reg[35].loc.offset = (long)&sc->sc_rets - new_cfa;
137 fs->regs.how[36] = REG_SAVED_OFFSET;
138 fs->regs.reg[36].loc.offset = (long)&sc->sc_pc - new_cfa;
139 fs->regs.how[37] = REG_SAVED_OFFSET;
140 fs->regs.reg[37].loc.offset = (long)&sc->sc_retx - new_cfa;
141
142 fs->regs.how[40] = REG_SAVED_OFFSET;
143 fs->regs.reg[40].loc.offset = (long)&sc->sc_astat - new_cfa;
144 fs->regs.how[41] = REG_SAVED_OFFSET;
145 fs->regs.reg[41].loc.offset = (long)&sc->sc_seqstat - new_cfa;
146
147 fs->regs.how[44] = REG_SAVED_OFFSET;
148 fs->regs.reg[44].loc.offset = (long)&sc->sc_lt0 - new_cfa;
149 fs->regs.how[45] = REG_SAVED_OFFSET;
150 fs->regs.reg[45].loc.offset = (long)&sc->sc_lt1 - new_cfa;
151 fs->regs.how[46] = REG_SAVED_OFFSET;
152 fs->regs.reg[46].loc.offset = (long)&sc->sc_lc0 - new_cfa;
153 fs->regs.how[47] = REG_SAVED_OFFSET;
154 fs->regs.reg[47].loc.offset = (long)&sc->sc_lc1 - new_cfa;
155 fs->regs.how[48] = REG_SAVED_OFFSET;
156 fs->regs.reg[48].loc.offset = (long)&sc->sc_lb0 - new_cfa;
157 fs->regs.how[49] = REG_SAVED_OFFSET;
158 fs->regs.reg[49].loc.offset = (long)&sc->sc_lb1 - new_cfa;
159 fs->retaddr_column = 35;
160
161 return _URC_NO_REASON;
162 }
163
164 #endif /* ifdef inhibit_libc */