1/* libunwind - a platform-independent unwind library
2   Copyright (C) 2008 CodeSourcery
3   Copyright 2011 Linaro Limited
4   Copyright (C) 2012 Tommi Rantala <tt.rantala@gmail.com>
5
6This file is part of libunwind.
7
8Permission is hereby granted, free of charge, to any person obtaining
9a copy of this software and associated documentation files (the
10"Software"), to deal in the Software without restriction, including
11without limitation the rights to use, copy, modify, merge, publish,
12distribute, sublicense, and/or sell copies of the Software, and to
13permit persons to whom the Software is furnished to do so, subject to
14the following conditions:
15
16The above copyright notice and this permission notice shall be
17included in all copies or substantial portions of the Software.
18
19THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
22NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
23LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
24OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
25WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
26
27#include "unwind_i.h"
28#include "offsets.h"
29
30#ifndef UNW_REMOTE_ONLY
31
32HIDDEN inline int
33sh_local_resume (unw_addr_space_t as, unw_cursor_t *cursor, void *arg)
34{
35#ifdef __linux__
36  struct cursor *c = (struct cursor *) cursor;
37  unw_tdep_context_t *uc = c->dwarf.as_arg;
38
39  if (c->sigcontext_format == SH_SCF_NONE)
40    {
41      /* Since there are no signals involved here we restore the non scratch
42	 registers only.  */
43      unsigned long regs[8];
44      regs[0] = uc->uc_mcontext.gregs[8];
45      regs[1] = uc->uc_mcontext.gregs[9];
46      regs[2] = uc->uc_mcontext.gregs[10];
47      regs[3] = uc->uc_mcontext.gregs[11];
48      regs[4] = uc->uc_mcontext.gregs[12];
49      regs[5] = uc->uc_mcontext.gregs[13];
50      regs[6] = uc->uc_mcontext.gregs[14];
51      regs[7] = uc->uc_mcontext.gregs[15];
52      unsigned long pc = uc->uc_mcontext.pr;
53
54      struct regs_overlay {
55	char x[sizeof(regs)];
56      };
57
58      asm volatile (
59	"mov.l @%0+, r8\n"
60	"mov.l @%0+, r9\n"
61	"mov.l @%0+, r10\n"
62	"mov.l @%0+, r11\n"
63	"mov.l @%0+, r12\n"
64	"mov.l @%0+, r13\n"
65	"mov.l @%0+, r14\n"
66	"mov.l @%0,  r15\n"
67	"lds %1, pr\n"
68	"rts\n"
69	"nop\n"
70	:
71	: "r" (regs),
72	  "r" (pc),
73	  "m" (*(struct regs_overlay *)regs)
74      );
75    }
76  else
77    {
78      /* In case a signal frame is involved, we're using its trampoline which
79	 calls sigreturn.  */
80      struct sigcontext *sc = (struct sigcontext *) c->sigcontext_addr;
81      sc->sc_regs[0] = uc->uc_mcontext.gregs[0];
82      sc->sc_regs[1] = uc->uc_mcontext.gregs[1];
83      sc->sc_regs[2] = uc->uc_mcontext.gregs[2];
84      sc->sc_regs[3] = uc->uc_mcontext.gregs[3];
85      sc->sc_regs[4] = uc->uc_mcontext.gregs[4];
86      sc->sc_regs[5] = uc->uc_mcontext.gregs[5];
87      sc->sc_regs[6] = uc->uc_mcontext.gregs[6];
88      sc->sc_regs[7] = uc->uc_mcontext.gregs[7];
89      sc->sc_regs[8] = uc->uc_mcontext.gregs[8];
90      sc->sc_regs[9] = uc->uc_mcontext.gregs[9];
91      sc->sc_regs[10] = uc->uc_mcontext.gregs[10];
92      sc->sc_regs[11] = uc->uc_mcontext.gregs[11];
93      sc->sc_regs[12] = uc->uc_mcontext.gregs[12];
94      sc->sc_regs[13] = uc->uc_mcontext.gregs[13];
95      sc->sc_regs[14] = uc->uc_mcontext.gregs[14];
96      sc->sc_regs[15] = uc->uc_mcontext.gregs[15];
97      sc->sc_pc = uc->uc_mcontext.pc;
98      sc->sc_pr = uc->uc_mcontext.pr;
99
100      /* Set the SP and the PC in order to continue execution at the modified
101	 trampoline which restores the signal mask and the registers.  */
102      asm __volatile__ (
103	"mov %0, r15\n"
104	"lds %1, pr\n"
105	"rts\n"
106	"nop\n"
107	:
108	: "r" (c->sigcontext_sp),
109	  "r" (c->sigcontext_pc)
110      );
111   }
112  unreachable();
113#endif
114  return -UNW_EINVAL;
115}
116
117#endif /* !UNW_REMOTE_ONLY */
118
119static inline void
120establish_machine_state (struct cursor *c)
121{
122  unw_addr_space_t as = c->dwarf.as;
123  void *arg = c->dwarf.as_arg;
124  unw_fpreg_t fpval;
125  unw_word_t val;
126  int reg;
127
128  Debug (8, "copying out cursor state\n");
129
130  for (reg = 0; reg <= UNW_REG_LAST; ++reg)
131    {
132      Debug (16, "copying %s %d\n", unw_regname (reg), reg);
133      if (unw_is_fpreg (reg))
134	{
135	  if (tdep_access_fpreg (c, reg, &fpval, 0) >= 0)
136	    as->acc.access_fpreg (as, reg, &fpval, 1, arg);
137	}
138      else
139	{
140	  if (tdep_access_reg (c, reg, &val, 0) >= 0)
141	    as->acc.access_reg (as, reg, &val, 1, arg);
142	}
143    }
144}
145
146PROTECTED int
147unw_resume (unw_cursor_t *cursor)
148{
149  struct cursor *c = (struct cursor *) cursor;
150
151  Debug (1, "(cursor=%p)\n", c);
152
153  if (!c->dwarf.ip)
154    {
155      /* This can happen easily when the frame-chain gets truncated
156	 due to bad or missing unwind-info.  */
157      Debug (1, "refusing to resume execution at address 0\n");
158      return -UNW_EINVAL;
159    }
160
161  establish_machine_state (c);
162
163  return (*c->dwarf.as->acc.resume) (c->dwarf.as, (unw_cursor_t *) c,
164				     c->dwarf.as_arg);
165}
166