1 /* DWARF2 EH unwinding support for IA64 Linux.
2 Copyright (C) 2004, 2005 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 it
7 under the terms of the GNU General Public License as published
8 by the Free Software Foundation; either version 2, or (at your
9 option) any later version.
10
11 In addition to the permissions in the GNU General Public License,
12 the Free Software Foundation gives you unlimited permission to link
13 the compiled version of this file with other programs, and to
14 distribute those programs without any restriction coming from the
15 use of this file. (The General Public License restrictions do
16 apply in other respects; for example, they cover modification of
17 the file, and distribution when not linked into another program.)
18
19 GCC is distributed in the hope that it will be useful, but WITHOUT
20 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
21 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
22 License for more details.
23
24 You should have received a copy of the GNU General Public License
25 along with GCC; see the file COPYING. If not, write to the
26 Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
27 MA 02110-1301, USA. */
28
29 /* Do code reading to identify a signal frame, and set the frame
30 state data appropriately. See unwind-dw2.c for the structs. */
31
32 /* This works only for glibc-2.3 and later, because sigcontext is different
33 in glibc-2.2.4. */
34
35 #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 3)
36 #include <signal.h>
37 #include <sys/ucontext.h>
38
39 #define IA64_GATE_AREA_START 0xa000000000000100LL
40 #define IA64_GATE_AREA_END 0xa000000000030000LL
41
42 #define MD_FALLBACK_FRAME_STATE_FOR ia64_fallback_frame_state
43
44 static _Unwind_Reason_Code
ia64_fallback_frame_state(struct _Unwind_Context * context,_Unwind_FrameState * fs)45 ia64_fallback_frame_state (struct _Unwind_Context *context,
46 _Unwind_FrameState *fs)
47 {
48 if (context->rp >= IA64_GATE_AREA_START
49 && context->rp < IA64_GATE_AREA_END)
50 {
51 struct sigframe {
52 char scratch[16];
53 unsigned long sig_number;
54 struct siginfo *info;
55 struct sigcontext *sc;
56 } *frame_ = (struct sigframe *)context->psp;
57 struct sigcontext *sc = frame_->sc;
58
59 /* Restore scratch registers in case the unwinder needs to
60 refer to a value stored in one of them. */
61 {
62 int i;
63
64 for (i = 2; i < 4; i++)
65 context->ireg[i - 2].loc = &sc->sc_gr[i];
66 for (i = 8; i < 12; i++)
67 context->ireg[i - 2].loc = &sc->sc_gr[i];
68 for (i = 14; i < 32; i++)
69 context->ireg[i - 2].loc = &sc->sc_gr[i];
70 }
71
72 context->fpsr_loc = &(sc->sc_ar_fpsr);
73 context->pfs_loc = &(sc->sc_ar_pfs);
74 context->lc_loc = &(sc->sc_ar_lc);
75 context->unat_loc = &(sc->sc_ar_unat);
76 context->br_loc[0] = &(sc->sc_br[0]);
77 context->br_loc[6] = &(sc->sc_br[6]);
78 context->br_loc[7] = &(sc->sc_br[7]);
79 context->pr = sc->sc_pr;
80 context->psp = sc->sc_gr[12];
81 context->gp = sc->sc_gr[1];
82 /* Signal frame doesn't have an associated reg. stack frame
83 other than what we adjust for below. */
84 fs -> no_reg_stack_frame = 1;
85
86 if (sc->sc_rbs_base)
87 {
88 /* Need to switch from alternate register backing store. */
89 long ndirty, loadrs = sc->sc_loadrs >> 16;
90 unsigned long alt_bspstore = context->bsp - loadrs;
91 unsigned long bspstore;
92 unsigned long *ar_bsp = (unsigned long *)(sc->sc_ar_bsp);
93
94 ndirty = ia64_rse_num_regs ((unsigned long *) alt_bspstore,
95 (unsigned long *) context->bsp);
96 bspstore = (unsigned long)
97 ia64_rse_skip_regs (ar_bsp, -ndirty);
98 ia64_copy_rbs (context, bspstore, alt_bspstore, loadrs,
99 sc->sc_ar_rnat);
100 }
101
102 /* Don't touch the branch registers o.t. b0, b6 and b7.
103 The kernel doesn't pass the preserved branch registers
104 in the sigcontext but leaves them intact, so there's no
105 need to do anything with them here. */
106 {
107 unsigned long sof = sc->sc_cfm & 0x7f;
108 context->bsp = (unsigned long)
109 ia64_rse_skip_regs ((unsigned long *)(sc->sc_ar_bsp), -sof);
110 }
111
112 fs->curr.reg[UNW_REG_RP].where = UNW_WHERE_SPREL;
113 fs->curr.reg[UNW_REG_RP].val
114 = (unsigned long)&(sc->sc_ip) - context->psp;
115 fs->curr.reg[UNW_REG_RP].when = -1;
116
117 return _URC_NO_REASON;
118 }
119 return _URC_END_OF_STACK;
120 }
121
122 #define MD_HANDLE_UNWABI ia64_handle_unwabi
123
124 static void
ia64_handle_unwabi(struct _Unwind_Context * context,_Unwind_FrameState * fs)125 ia64_handle_unwabi (struct _Unwind_Context *context, _Unwind_FrameState *fs)
126 {
127 if (fs->unwabi == ((3 << 8) | 's')
128 || fs->unwabi == ((0 << 8) | 's'))
129 {
130 struct sigframe {
131 char scratch[16];
132 unsigned long sig_number;
133 struct siginfo *info;
134 struct sigcontext *sc;
135 } *frame = (struct sigframe *)context->psp;
136 struct sigcontext *sc = frame->sc;
137
138 /* Restore scratch registers in case the unwinder needs to
139 refer to a value stored in one of them. */
140 {
141 int i;
142
143 for (i = 2; i < 4; i++)
144 context->ireg[i - 2].loc = &sc->sc_gr[i];
145 for (i = 8; i < 12; i++)
146 context->ireg[i - 2].loc = &sc->sc_gr[i];
147 for (i = 14; i < 32; i++)
148 context->ireg[i - 2].loc = &sc->sc_gr[i];
149 }
150
151 context->pfs_loc = &(sc->sc_ar_pfs);
152 context->lc_loc = &(sc->sc_ar_lc);
153 context->unat_loc = &(sc->sc_ar_unat);
154 context->br_loc[0] = &(sc->sc_br[0]);
155 context->br_loc[6] = &(sc->sc_br[6]);
156 context->br_loc[7] = &(sc->sc_br[7]);
157 context->pr = sc->sc_pr;
158 context->gp = sc->sc_gr[1];
159 /* Signal frame doesn't have an associated reg. stack frame
160 other than what we adjust for below. */
161 fs -> no_reg_stack_frame = 1;
162
163 if (sc->sc_rbs_base)
164 {
165 /* Need to switch from alternate register backing store. */
166 long ndirty, loadrs = sc->sc_loadrs >> 16;
167 unsigned long alt_bspstore = context->bsp - loadrs;
168 unsigned long bspstore;
169 unsigned long *ar_bsp = (unsigned long *)(sc->sc_ar_bsp);
170
171 ndirty = ia64_rse_num_regs ((unsigned long *) alt_bspstore,
172 (unsigned long *) context->bsp);
173 bspstore = (unsigned long) ia64_rse_skip_regs (ar_bsp, -ndirty);
174 ia64_copy_rbs (context, bspstore, alt_bspstore, loadrs,
175 sc->sc_ar_rnat);
176 }
177
178 /* Don't touch the branch registers o.t. b0, b6 and b7.
179 The kernel doesn't pass the preserved branch registers
180 in the sigcontext but leaves them intact, so there's no
181 need to do anything with them here. */
182 {
183 unsigned long sof = sc->sc_cfm & 0x7f;
184 context->bsp = (unsigned long)
185 ia64_rse_skip_regs ((unsigned long *)(sc->sc_ar_bsp), -sof);
186 }
187
188 /* pfs_loc already set above. Without this pfs_loc would point
189 incorrectly to sc_cfm instead of sc_ar_pfs. */
190 fs->curr.reg[UNW_REG_PFS].where = UNW_WHERE_NONE;
191 }
192 }
193 #endif /* glibc-2.3 or better */
194