OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [gcc-4.2.2/] [gcc/] [config/] [s390/] [tpf-unwind.h] - Blame information for rev 38

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 38 julius
/* DWARF2 EH unwinding support for TPF OS.
2
   Copyright (C) 2004, 2005 Free Software Foundation, Inc.
3
   Contributed by P.J. Darcy (darcypj@us.ibm.com).
4
 
5
This file is part of GCC.
6
 
7
GCC is free software; you can redistribute it and/or modify it under
8
the terms of the GNU General Public License as published by the Free
9
Software Foundation; either version 2, or (at your option) any later
10
version.
11
 
12
In addition to the permissions in the GNU General Public License, the
13
Free Software Foundation gives you unlimited permission to link the
14
compiled version of this file into combinations with other programs,
15
and to distribute those combinations without any restriction coming
16
from the use of this file.  (The General Public License restrictions
17
do apply in other respects; for example, they cover modification of
18
the file, and distribution when not linked into a combined
19
executable.)
20
 
21
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
22
WARRANTY; without even the implied warranty of MERCHANTABILITY or
23
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
24
for more details.
25
 
26
You should have received a copy of the GNU General Public License
27
along with GCC; see the file COPYING.  If not, write to the Free
28
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
29
02110-1301, USA.  */
30
 
31
#include <dlfcn.h>
32
 
33
/* Function Name: __isPATrange
34
   Parameters passed into it:  address to check
35
   Return Value: A 1 if address is in pat code "range", 0 if not
36
   Description: This function simply checks to see if the address
37
   passed to it is in the CP pat code range.  */
38
 
39
#define MIN_PATRANGE 0x10000
40
#define MAX_PATRANGE 0x800000
41
 
42
static inline unsigned int
43
__isPATrange (void *addr)
44
{
45
  if (addr > (void *)MIN_PATRANGE && addr < (void *)MAX_PATRANGE)
46
    return 1;
47
  else
48
    return 0;
49
}
50
 
51
/* TPF return address offset from start of stack frame.  */
52
#define TPFRA_OFFSET 168
53
 
54
/* Exceptions macro defined for TPF so that functions without
55
   dwarf frame information can be used with exceptions.  */
56
#define MD_FALLBACK_FRAME_STATE_FOR s390_fallback_frame_state
57
 
58
static _Unwind_Reason_Code
59
s390_fallback_frame_state (struct _Unwind_Context *context,
60
                           _Unwind_FrameState *fs)
61
{
62
  unsigned long int regs;
63
  unsigned long int new_cfa;
64
  int i;
65
 
66
  regs = *((unsigned long int *)
67
        (((unsigned long int) context->cfa) - STACK_POINTER_OFFSET));
68
 
69
  /* Are we going through special linkage code?  */
70
  if (__isPATrange (context->ra))
71
    {
72
 
73
      /* Our return register isn't zero for end of stack, so
74
         check backward stackpointer to see if it is zero.  */
75
      if (regs == NULL)
76
         return _URC_END_OF_STACK;
77
 
78
      /* No stack frame.  */
79
      fs->cfa_how = CFA_REG_OFFSET;
80
      fs->cfa_reg = 15;
81
      fs->cfa_offset = STACK_POINTER_OFFSET;
82
 
83
      /* All registers remain unchanged ...  */
84
      for (i = 0; i < 32; i++)
85
        {
86
          fs->regs.reg[i].how = REG_SAVED_REG;
87
          fs->regs.reg[i].loc.reg = i;
88
        }
89
 
90
      /* ... except for %r14, which is stored at CFA-112
91
         and used as return address.  */
92
      fs->regs.reg[14].how = REG_SAVED_OFFSET;
93
      fs->regs.reg[14].loc.offset = TPFRA_OFFSET - STACK_POINTER_OFFSET;
94
      fs->retaddr_column = 14;
95
 
96
      return _URC_NO_REASON;
97
    }
98
 
99
  regs = *((unsigned long int *)
100
        (((unsigned long int) context->cfa) - STACK_POINTER_OFFSET));
101
  new_cfa = regs + STACK_POINTER_OFFSET;
102
 
103
  fs->cfa_how = CFA_REG_OFFSET;
104
  fs->cfa_reg = 15;
105
  fs->cfa_offset = new_cfa -
106
        (unsigned long int) context->cfa + STACK_POINTER_OFFSET;
107
 
108
  for (i = 0; i < 16; i++)
109
    {
110
      fs->regs.reg[i].how = REG_SAVED_OFFSET;
111
      fs->regs.reg[i].loc.offset = regs + i*8 - new_cfa;
112
    }
113
 
114
  for (i = 0; i < 4; i++)
115
    {
116
      fs->regs.reg[16 + i].how = REG_SAVED_OFFSET;
117
      fs->regs.reg[16 + i].loc.offset = regs + 16*8 + i*8 - new_cfa;
118
    }
119
 
120
  fs->retaddr_column = 14;
121
 
122
  return _URC_NO_REASON;
123
}
124
 
125
/* Function Name: __tpf_eh_return
126
   Parameters passed into it: Destination address to jump to.
127
   Return Value: Converted Destination address if a Pat Stub exists.
128
   Description: This function swaps the unwinding return address
129
      with the cp stub code.  The original target return address is
130
      then stored into the tpf return address field.  The cp stub
131
      code is searched for by climbing back up the stack and
132
      comparing the tpf stored return address object address to
133
      that of the targets object address.  */
134
 
135
#define CURRENT_STACK_PTR() \
136
  ({ register unsigned long int *stack_ptr asm ("%r15"); stack_ptr; })
137
 
138
#define PREVIOUS_STACK_PTR() \
139
  ((unsigned long int *)(*(CURRENT_STACK_PTR())))
140
 
141
#define RA_OFFSET 112
142
#define R15_OFFSET 120
143
#define TPFAREA_OFFSET 160
144
#define TPFAREA_SIZE STACK_POINTER_OFFSET-TPFAREA_OFFSET
145
#define INVALID_RETURN 0
146
 
147
void * __tpf_eh_return (void *target);
148
 
149
void *
150
__tpf_eh_return (void *target)
151
{
152
  Dl_info targetcodeInfo, currentcodeInfo;
153
  int retval;
154
  void *current, *stackptr, *destination_frame;
155
  unsigned long int shifter, is_a_stub;
156
 
157
  is_a_stub = 0;
158
 
159
  /* Get code info for target return's address.  */
160
  retval = dladdr (target, &targetcodeInfo);
161
 
162
  /* Ensure the code info is valid (for target).  */
163
  if (retval != INVALID_RETURN)
164
    {
165
 
166
      /* Get the stack pointer of the stack frame to be modified by
167
         the exception unwinder.  So that we can begin our climb
168
         there.  */
169
      stackptr = (void *) *((unsigned long int *) (*(PREVIOUS_STACK_PTR())));
170
 
171
      /* Begin looping through stack frames.  Stop if invalid
172
         code information is retrieved or if a match between the
173
         current stack frame iteration shared object's address
174
         matches that of the target, calculated above.  */
175
      do
176
        {
177
          /* Get return address based on our stackptr iterator.  */
178
          current = (void *) *((unsigned long int *)
179
                      (stackptr+RA_OFFSET));
180
 
181
          /* Is it a Pat Stub?  */
182
          if (__isPATrange (current))
183
            {
184
              /* Yes it was, get real return address
185
                 in TPF stack area.  */
186
              current = (void *) *((unsigned long int *)
187
                          (stackptr+TPFRA_OFFSET));
188
              is_a_stub = 1;
189
            }
190
 
191
          /* Get codeinfo on RA so that we can figure out
192
             the module address.  */
193
          retval = dladdr (current, &currentcodeInfo);
194
 
195
          /* Check that codeinfo for current stack frame is valid.
196
             Then compare the module address of current stack frame
197
             to target stack frame to determine if we have the pat
198
             stub address we want.  Also ensure we are dealing
199
             with a module crossing, stub return address. */
200
          if (is_a_stub && retval != INVALID_RETURN
201
             && targetcodeInfo.dli_fbase == currentcodeInfo.dli_fbase)
202
             {
203
               /* Yes! They are in the same module.
204
                  Force copy of TPF private stack area to
205
                  destination stack frame TPF private area. */
206
               destination_frame = (void *) *((unsigned long int *)
207
                   (*PREVIOUS_STACK_PTR() + R15_OFFSET));
208
 
209
               /* Copy TPF linkage area from current frame to
210
                  destination frame.  */
211
               memcpy((void *) (destination_frame + TPFAREA_OFFSET),
212
                 (void *) (stackptr + TPFAREA_OFFSET), TPFAREA_SIZE);
213
 
214
               /* Now overlay the
215
                  real target address into the TPF stack area of
216
                  the target frame we are jumping to.  */
217
               *((unsigned long int *) (destination_frame +
218
                   TPFRA_OFFSET)) = (unsigned long int) target;
219
 
220
               /* Before returning the desired pat stub address to
221
                  the exception handling unwinder so that it can
222
                  actually do the "leap" shift out the low order
223
                  bit designated to determine if we are in 64BIT mode.
224
                  This is necessary for CTOA stubs.
225
                  Otherwise we leap one byte past where we want to
226
                  go to in the TPF pat stub linkage code.  */
227
               shifter = *((unsigned long int *)
228
                     (stackptr + RA_OFFSET));
229
 
230
               shifter &= ~1ul;
231
 
232
               /* Store Pat Stub Address in destination Stack Frame.  */
233
               *((unsigned long int *) (destination_frame +
234
                   RA_OFFSET)) = shifter;
235
 
236
               /* Re-adjust pat stub address to go to correct place
237
                  in linkage.  */
238
               shifter = shifter - 4;
239
 
240
               return (void *) shifter;
241
             }
242
 
243
          /* Desired module pat stub not found ...
244
             Bump stack frame iterator.  */
245
          stackptr = (void *) *(unsigned long int *) stackptr;
246
 
247
          is_a_stub = 0;
248
 
249
        }  while (stackptr && retval != INVALID_RETURN
250
                && targetcodeInfo.dli_fbase != currentcodeInfo.dli_fbase);
251
    }
252
 
253
  /* No pat stub found, could be a problem?  Simply return unmodified
254
     target address.  */
255
  return target;
256
}
257
 

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.