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[/] [openrisc/] [trunk/] [gnu-src/] [gdb-7.2/] [gdb/] [xstormy16-tdep.c] - Blame information for rev 359

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1 330 jeremybenn
/* Target-dependent code for the Sanyo Xstormy16a (LC590000) processor.
2
 
3
   Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
4
   Free Software Foundation, Inc.
5
 
6
   This file is part of GDB.
7
 
8
   This program is free software; you can redistribute it and/or modify
9
   it under the terms of the GNU General Public License as published by
10
   the Free Software Foundation; either version 3 of the License, or
11
   (at your option) any later version.
12
 
13
   This program is distributed in the hope that it will be useful,
14
   but WITHOUT ANY WARRANTY; without even the implied warranty of
15
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16
   GNU General Public License for more details.
17
 
18
   You should have received a copy of the GNU General Public License
19
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20
 
21
#include "defs.h"
22
#include "frame.h"
23
#include "frame-base.h"
24
#include "frame-unwind.h"
25
#include "dwarf2-frame.h"
26
#include "symtab.h"
27
#include "gdbtypes.h"
28
#include "gdbcmd.h"
29
#include "gdbcore.h"
30
#include "value.h"
31
#include "dis-asm.h"
32
#include "inferior.h"
33
#include "gdb_string.h"
34
#include "gdb_assert.h"
35
#include "arch-utils.h"
36
#include "floatformat.h"
37
#include "regcache.h"
38
#include "doublest.h"
39
#include "osabi.h"
40
#include "objfiles.h"
41
 
42
enum gdb_regnum
43
{
44
  /* Xstormy16 has 16 general purpose registers (R0-R15) plus PC.
45
     Functions will return their values in register R2-R7 as they fit.
46
     Otherwise a hidden pointer to an big enough area is given as argument
47
     to the function in r2. Further arguments are beginning in r3 then.
48
     R13 is used as frame pointer when GCC compiles w/o optimization
49
     R14 is used as "PSW", displaying the CPU status.
50
     R15 is used implicitely as stack pointer. */
51
  E_R0_REGNUM,
52
  E_R1_REGNUM,
53
  E_R2_REGNUM, E_1ST_ARG_REGNUM = E_R2_REGNUM, E_PTR_RET_REGNUM = E_R2_REGNUM,
54
  E_R3_REGNUM,
55
  E_R4_REGNUM,
56
  E_R5_REGNUM,
57
  E_R6_REGNUM,
58
  E_R7_REGNUM, E_LST_ARG_REGNUM = E_R7_REGNUM,
59
  E_R8_REGNUM,
60
  E_R9_REGNUM,
61
  E_R10_REGNUM,
62
  E_R11_REGNUM,
63
  E_R12_REGNUM,
64
  E_R13_REGNUM, E_FP_REGNUM = E_R13_REGNUM,
65
  E_R14_REGNUM, E_PSW_REGNUM = E_R14_REGNUM,
66
  E_R15_REGNUM, E_SP_REGNUM = E_R15_REGNUM,
67
  E_PC_REGNUM,
68
  E_NUM_REGS
69
};
70
 
71
/* Use an invalid address value as 'not available' marker.  */
72
enum { REG_UNAVAIL = (CORE_ADDR) -1 };
73
 
74
struct xstormy16_frame_cache
75
{
76
  /* Base address.  */
77
  CORE_ADDR base;
78
  CORE_ADDR pc;
79
  LONGEST framesize;
80
  int uses_fp;
81
  CORE_ADDR saved_regs[E_NUM_REGS];
82
  CORE_ADDR saved_sp;
83
};
84
 
85
/* Size of instructions, registers, etc. */
86
enum
87
{
88
  xstormy16_inst_size = 2,
89
  xstormy16_reg_size = 2,
90
  xstormy16_pc_size = 4
91
};
92
 
93
/* Size of return datatype which fits into the remaining return registers. */
94
#define E_MAX_RETTYPE_SIZE(regnum)      ((E_LST_ARG_REGNUM - (regnum) + 1) \
95
                                        * xstormy16_reg_size)
96
 
97
/* Size of return datatype which fits into all return registers. */
98
enum
99
{
100
  E_MAX_RETTYPE_SIZE_IN_REGS = E_MAX_RETTYPE_SIZE (E_R2_REGNUM)
101
};
102
 
103
/* Function: xstormy16_register_name
104
   Returns the name of the standard Xstormy16 register N.  */
105
 
106
static const char *
107
xstormy16_register_name (struct gdbarch *gdbarch, int regnum)
108
{
109
  static char *register_names[] = {
110
    "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
111
    "r8", "r9", "r10", "r11", "r12", "r13",
112
    "psw", "sp", "pc"
113
  };
114
 
115
  if (regnum < 0 || regnum >= E_NUM_REGS)
116
    internal_error (__FILE__, __LINE__,
117
                    _("xstormy16_register_name: illegal register number %d"),
118
                    regnum);
119
  else
120
    return register_names[regnum];
121
 
122
}
123
 
124
static struct type *
125
xstormy16_register_type (struct gdbarch *gdbarch, int regnum)
126
{
127
  if (regnum == E_PC_REGNUM)
128
    return builtin_type (gdbarch)->builtin_uint32;
129
  else
130
    return builtin_type (gdbarch)->builtin_uint16;
131
}
132
 
133
/* Function: xstormy16_type_is_scalar
134
   Makes the decision if a given type is a scalar types.  Scalar
135
   types are returned in the registers r2-r7 as they fit.  */
136
 
137
static int
138
xstormy16_type_is_scalar (struct type *t)
139
{
140
  return (TYPE_CODE(t) != TYPE_CODE_STRUCT
141
          && TYPE_CODE(t) != TYPE_CODE_UNION
142
          && TYPE_CODE(t) != TYPE_CODE_ARRAY);
143
}
144
 
145
/* Function: xstormy16_use_struct_convention
146
   Returns non-zero if the given struct type will be returned using
147
   a special convention, rather than the normal function return method.
148
   7sed in the contexts of the "return" command, and of
149
   target function calls from the debugger.  */
150
 
151
static int
152
xstormy16_use_struct_convention (struct type *type)
153
{
154
  return !xstormy16_type_is_scalar (type)
155
         || TYPE_LENGTH (type) > E_MAX_RETTYPE_SIZE_IN_REGS;
156
}
157
 
158
/* Function: xstormy16_extract_return_value
159
   Find a function's return value in the appropriate registers (in
160
   regbuf), and copy it into valbuf.  */
161
 
162
static void
163
xstormy16_extract_return_value (struct type *type, struct regcache *regcache,
164
                                void *valbuf)
165
{
166
  int len = TYPE_LENGTH (type);
167
  int i, regnum = E_1ST_ARG_REGNUM;
168
 
169
  for (i = 0; i < len; i += xstormy16_reg_size)
170
    regcache_raw_read (regcache, regnum++, (char *) valbuf + i);
171
}
172
 
173
/* Function: xstormy16_store_return_value
174
   Copy the function return value from VALBUF into the
175
   proper location for a function return.
176
   Called only in the context of the "return" command.  */
177
 
178
static void
179
xstormy16_store_return_value (struct type *type, struct regcache *regcache,
180
                              const void *valbuf)
181
{
182
  if (TYPE_LENGTH (type) == 1)
183
    {
184
      /* Add leading zeros to the value. */
185
      char buf[xstormy16_reg_size];
186
      memset (buf, 0, xstormy16_reg_size);
187
      memcpy (buf, valbuf, 1);
188
      regcache_raw_write (regcache, E_1ST_ARG_REGNUM, buf);
189
    }
190
  else
191
    {
192
      int len = TYPE_LENGTH (type);
193
      int i, regnum = E_1ST_ARG_REGNUM;
194
 
195
      for (i = 0; i < len; i += xstormy16_reg_size)
196
        regcache_raw_write (regcache, regnum++, (char *) valbuf + i);
197
    }
198
}
199
 
200
static enum return_value_convention
201
xstormy16_return_value (struct gdbarch *gdbarch, struct type *func_type,
202
                        struct type *type, struct regcache *regcache,
203
                        gdb_byte *readbuf, const gdb_byte *writebuf)
204
{
205
  if (xstormy16_use_struct_convention (type))
206
    return RETURN_VALUE_STRUCT_CONVENTION;
207
  if (writebuf)
208
    xstormy16_store_return_value (type, regcache, writebuf);
209
  else if (readbuf)
210
    xstormy16_extract_return_value (type, regcache, readbuf);
211
  return RETURN_VALUE_REGISTER_CONVENTION;
212
}
213
 
214
static CORE_ADDR
215
xstormy16_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
216
{
217
  if (addr & 1)
218
    ++addr;
219
  return addr;
220
}
221
 
222
/* Function: xstormy16_push_dummy_call
223
   Setup the function arguments for GDB to call a function in the inferior.
224
   Called only in the context of a target function call from the debugger.
225
   Returns the value of the SP register after the args are pushed.  */
226
 
227
static CORE_ADDR
228
xstormy16_push_dummy_call (struct gdbarch *gdbarch,
229
                           struct value *function,
230
                           struct regcache *regcache,
231
                           CORE_ADDR bp_addr, int nargs,
232
                           struct value **args,
233
                           CORE_ADDR sp, int struct_return,
234
                           CORE_ADDR struct_addr)
235
{
236
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
237
  CORE_ADDR stack_dest = sp;
238
  int argreg = E_1ST_ARG_REGNUM;
239
  int i, j;
240
  int typelen, slacklen;
241
  const gdb_byte *val;
242
  char buf[xstormy16_pc_size];
243
 
244
  /* If struct_return is true, then the struct return address will
245
     consume one argument-passing register.  */
246
  if (struct_return)
247
    {
248
      regcache_cooked_write_unsigned (regcache, E_PTR_RET_REGNUM, struct_addr);
249
      argreg++;
250
    }
251
 
252
  /* Arguments are passed in R2-R7 as they fit. If an argument doesn't
253
     fit in the remaining registers we're switching over to the stack.
254
     No argument is put on stack partially and as soon as we switched
255
     over to stack no further argument is put in a register even if it
256
     would fit in the remaining unused registers.  */
257
  for (i = 0; i < nargs && argreg <= E_LST_ARG_REGNUM; i++)
258
    {
259
      typelen = TYPE_LENGTH (value_enclosing_type (args[i]));
260
      if (typelen > E_MAX_RETTYPE_SIZE (argreg))
261
        break;
262
 
263
      /* Put argument into registers wordwise. */
264
      val = value_contents (args[i]);
265
      for (j = 0; j < typelen; j += xstormy16_reg_size)
266
        regcache_cooked_write_unsigned (regcache, argreg++,
267
                        extract_unsigned_integer (val + j,
268
                                                  typelen - j ==
269
                                                  1 ? 1 :
270
                                                  xstormy16_reg_size,
271
                                                  byte_order));
272
    }
273
 
274
  /* Align SP */
275
  stack_dest = xstormy16_frame_align (gdbarch, stack_dest);
276
 
277
  /* Loop backwards through remaining arguments and push them on the stack,
278
     wordaligned.  */
279
  for (j = nargs - 1; j >= i; j--)
280
    {
281
      char *val;
282
 
283
      typelen = TYPE_LENGTH (value_enclosing_type (args[j]));
284
      slacklen = typelen & 1;
285
      val = alloca (typelen + slacklen);
286
      memcpy (val, value_contents (args[j]), typelen);
287
      memset (val + typelen, 0, slacklen);
288
 
289
      /* Now write this data to the stack. The stack grows upwards. */
290
      write_memory (stack_dest, val, typelen + slacklen);
291
      stack_dest += typelen + slacklen;
292
    }
293
 
294
  store_unsigned_integer (buf, xstormy16_pc_size, byte_order, bp_addr);
295
  write_memory (stack_dest, buf, xstormy16_pc_size);
296
  stack_dest += xstormy16_pc_size;
297
 
298
  /* Update stack pointer.  */
299
  regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, stack_dest);
300
 
301
  /* Return the new stack pointer minus the return address slot since
302
     that's what DWARF2/GCC uses as the frame's CFA.  */
303
  return stack_dest - xstormy16_pc_size;
304
}
305
 
306
/* Function: xstormy16_scan_prologue
307
   Decode the instructions within the given address range.
308
   Decide when we must have reached the end of the function prologue.
309
   If a frame_info pointer is provided, fill in its saved_regs etc.
310
 
311
   Returns the address of the first instruction after the prologue.  */
312
 
313
static CORE_ADDR
314
xstormy16_analyze_prologue (struct gdbarch *gdbarch,
315
                            CORE_ADDR start_addr, CORE_ADDR end_addr,
316
                            struct xstormy16_frame_cache *cache,
317
                            struct frame_info *this_frame)
318
{
319
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
320
  CORE_ADDR next_addr;
321
  ULONGEST inst, inst2;
322
  LONGEST offset;
323
  int regnum;
324
 
325
  /* Initialize framesize with size of PC put on stack by CALLF inst. */
326
  cache->saved_regs[E_PC_REGNUM] = 0;
327
  cache->framesize = xstormy16_pc_size;
328
 
329
  if (start_addr >= end_addr)
330
    return end_addr;
331
 
332
  for (next_addr = start_addr;
333
       next_addr < end_addr; next_addr += xstormy16_inst_size)
334
    {
335
      inst = read_memory_unsigned_integer (next_addr,
336
                                           xstormy16_inst_size, byte_order);
337
      inst2 = read_memory_unsigned_integer (next_addr + xstormy16_inst_size,
338
                                            xstormy16_inst_size, byte_order);
339
 
340
      if (inst >= 0x0082 && inst <= 0x008d)     /* push r2 .. push r13 */
341
        {
342
          regnum = inst & 0x000f;
343
          cache->saved_regs[regnum] = cache->framesize;
344
          cache->framesize += xstormy16_reg_size;
345
        }
346
 
347
      /* optional stack allocation for args and local vars <= 4 byte */
348
      else if (inst == 0x301f || inst == 0x303f)        /* inc r15, #0x1/#0x3 */
349
        {
350
          cache->framesize += ((inst & 0x0030) >> 4) + 1;
351
        }
352
 
353
      /* optional stack allocation for args and local vars > 4 && < 16 byte */
354
      else if ((inst & 0xff0f) == 0x510f)       /* 51Hf   add r15, #0xH */
355
        {
356
          cache->framesize += (inst & 0x00f0) >> 4;
357
        }
358
 
359
      /* optional stack allocation for args and local vars >= 16 byte */
360
      else if (inst == 0x314f && inst2 >= 0x0010)       /* 314f HHHH  add r15, #0xH */
361
        {
362
          cache->framesize += inst2;
363
          next_addr += xstormy16_inst_size;
364
        }
365
 
366
      else if (inst == 0x46fd)  /* mov r13, r15 */
367
        {
368
          cache->uses_fp = 1;
369
        }
370
 
371
      /* optional copying of args in r2-r7 to r10-r13 */
372
      /* Probably only in optimized case but legal action for prologue */
373
      else if ((inst & 0xff00) == 0x4600        /* 46SD   mov rD, rS */
374
               && (inst & 0x00f0) >= 0x0020 && (inst & 0x00f0) <= 0x0070
375
               && (inst & 0x000f) >= 0x00a0 && (inst & 0x000f) <= 0x000d)
376
        ;
377
 
378
      /* optional copying of args in r2-r7 to stack */
379
      /* 72DS HHHH   mov.b (rD, 0xHHHH), r(S-8) (bit3 always 1, bit2-0 = reg) */
380
      /* 73DS HHHH   mov.w (rD, 0xHHHH), r(S-8) */
381
      else if ((inst & 0xfed8) == 0x72d8 && (inst & 0x0007) >= 2)
382
        {
383
          regnum = inst & 0x0007;
384
          /* Only 12 of 16 bits of the argument are used for the
385
             signed offset. */
386
          offset = (LONGEST) (inst2 & 0x0fff);
387
          if (offset & 0x0800)
388
            offset -= 0x1000;
389
 
390
          cache->saved_regs[regnum] = cache->framesize + offset;
391
          next_addr += xstormy16_inst_size;
392
        }
393
 
394
      else                      /* Not a prologue instruction. */
395
        break;
396
    }
397
 
398
  return next_addr;
399
}
400
 
401
/* Function: xstormy16_skip_prologue
402
   If the input address is in a function prologue,
403
   returns the address of the end of the prologue;
404
   else returns the input address.
405
 
406
   Note: the input address is likely to be the function start,
407
   since this function is mainly used for advancing a breakpoint
408
   to the first line, or stepping to the first line when we have
409
   stepped into a function call.  */
410
 
411
static CORE_ADDR
412
xstormy16_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
413
{
414
  CORE_ADDR func_addr = 0, func_end = 0;
415
  char *func_name;
416
 
417
  if (find_pc_partial_function (pc, &func_name, &func_addr, &func_end))
418
    {
419
      struct symtab_and_line sal;
420
      struct symbol *sym;
421
      struct xstormy16_frame_cache cache;
422
      CORE_ADDR plg_end;
423
 
424
      memset (&cache, 0, sizeof cache);
425
 
426
      /* Don't trust line number debug info in frameless functions. */
427
      plg_end = xstormy16_analyze_prologue (gdbarch, func_addr, func_end,
428
                                            &cache, NULL);
429
      if (!cache.uses_fp)
430
        return plg_end;
431
 
432
      /* Found a function.  */
433
      sym = lookup_symbol (func_name, NULL, VAR_DOMAIN, NULL);
434
      /* Don't use line number debug info for assembly source files. */
435
      if (sym && SYMBOL_LANGUAGE (sym) != language_asm)
436
        {
437
          sal = find_pc_line (func_addr, 0);
438
          if (sal.end && sal.end < func_end)
439
            {
440
              /* Found a line number, use it as end of prologue.  */
441
              return sal.end;
442
            }
443
        }
444
      /* No useable line symbol.  Use result of prologue parsing method. */
445
      return plg_end;
446
    }
447
 
448
  /* No function symbol -- just return the PC. */
449
 
450
  return (CORE_ADDR) pc;
451
}
452
 
453
/* The epilogue is defined here as the area at the end of a function,
454
   either on the `ret' instruction itself or after an instruction which
455
   destroys the function's stack frame. */
456
static int
457
xstormy16_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
458
{
459
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
460
  CORE_ADDR func_addr = 0, func_end = 0;
461
 
462
  if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
463
    {
464
      ULONGEST inst, inst2;
465
      CORE_ADDR addr = func_end - xstormy16_inst_size;
466
 
467
      /* The Xstormy16 epilogue is max. 14 bytes long. */
468
      if (pc < func_end - 7 * xstormy16_inst_size)
469
        return 0;
470
 
471
      /* Check if we're on a `ret' instruction.  Otherwise it's
472
         too dangerous to proceed. */
473
      inst = read_memory_unsigned_integer (addr,
474
                                           xstormy16_inst_size, byte_order);
475
      if (inst != 0x0003)
476
        return 0;
477
 
478
      while ((addr -= xstormy16_inst_size) >= func_addr)
479
        {
480
          inst = read_memory_unsigned_integer (addr,
481
                                               xstormy16_inst_size, byte_order);
482
          if (inst >= 0x009a && inst <= 0x009d) /* pop r10...r13 */
483
            continue;
484
          if (inst == 0x305f || inst == 0x307f) /* dec r15, #0x1/#0x3 */
485
            break;
486
          inst2 = read_memory_unsigned_integer (addr - xstormy16_inst_size,
487
                                                xstormy16_inst_size, byte_order);
488
          if (inst2 == 0x314f && inst >= 0x8000)        /* add r15, neg. value */
489
            {
490
              addr -= xstormy16_inst_size;
491
              break;
492
            }
493
          return 0;
494
        }
495
      if (pc > addr)
496
        return 1;
497
    }
498
  return 0;
499
}
500
 
501
const static unsigned char *
502
xstormy16_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr,
503
                              int *lenptr)
504
{
505
  static unsigned char breakpoint[] = { 0x06, 0x0 };
506
  *lenptr = sizeof (breakpoint);
507
  return breakpoint;
508
}
509
 
510
/* Given a pointer to a jump table entry, return the address
511
   of the function it jumps to.  Return 0 if not found. */
512
static CORE_ADDR
513
xstormy16_resolve_jmp_table_entry (struct gdbarch *gdbarch, CORE_ADDR faddr)
514
{
515
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
516
  struct obj_section *faddr_sect = find_pc_section (faddr);
517
 
518
  if (faddr_sect)
519
    {
520
      LONGEST inst, inst2, addr;
521
      char buf[2 * xstormy16_inst_size];
522
 
523
      /* Return faddr if it's not pointing into the jump table. */
524
      if (strcmp (faddr_sect->the_bfd_section->name, ".plt"))
525
        return faddr;
526
 
527
      if (!target_read_memory (faddr, buf, sizeof buf))
528
        {
529
          inst = extract_unsigned_integer (buf,
530
                                           xstormy16_inst_size, byte_order);
531
          inst2 = extract_unsigned_integer (buf + xstormy16_inst_size,
532
                                            xstormy16_inst_size, byte_order);
533
          addr = inst2 << 8 | (inst & 0xff);
534
          return addr;
535
        }
536
    }
537
  return 0;
538
}
539
 
540
/* Given a function's address, attempt to find (and return) the
541
   address of the corresponding jump table entry.  Return 0 if
542
   not found. */
543
static CORE_ADDR
544
xstormy16_find_jmp_table_entry (struct gdbarch *gdbarch, CORE_ADDR faddr)
545
{
546
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
547
  struct obj_section *faddr_sect = find_pc_section (faddr);
548
 
549
  if (faddr_sect)
550
    {
551
      struct obj_section *osect;
552
 
553
      /* Return faddr if it's already a pointer to a jump table entry. */
554
      if (!strcmp (faddr_sect->the_bfd_section->name, ".plt"))
555
        return faddr;
556
 
557
      ALL_OBJFILE_OSECTIONS (faddr_sect->objfile, osect)
558
      {
559
        if (!strcmp (osect->the_bfd_section->name, ".plt"))
560
          break;
561
      }
562
 
563
      if (osect < faddr_sect->objfile->sections_end)
564
        {
565
          CORE_ADDR addr, endaddr;
566
 
567
          addr = obj_section_addr (osect);
568
          endaddr = obj_section_endaddr (osect);
569
 
570
          for (; addr < endaddr; addr += 2 * xstormy16_inst_size)
571
            {
572
              LONGEST inst, inst2, faddr2;
573
              char buf[2 * xstormy16_inst_size];
574
 
575
              if (target_read_memory (addr, buf, sizeof buf))
576
                return 0;
577
              inst = extract_unsigned_integer (buf,
578
                                               xstormy16_inst_size, byte_order);
579
              inst2 = extract_unsigned_integer (buf + xstormy16_inst_size,
580
                                                xstormy16_inst_size, byte_order);
581
              faddr2 = inst2 << 8 | (inst & 0xff);
582
              if (faddr == faddr2)
583
                return addr;
584
            }
585
        }
586
    }
587
  return 0;
588
}
589
 
590
static CORE_ADDR
591
xstormy16_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
592
{
593
  struct gdbarch *gdbarch = get_frame_arch (frame);
594
  CORE_ADDR tmp = xstormy16_resolve_jmp_table_entry (gdbarch, pc);
595
 
596
  if (tmp && tmp != pc)
597
    return tmp;
598
  return 0;
599
}
600
 
601
/* Function pointers are 16 bit.  The address space is 24 bit, using
602
   32 bit addresses.  Pointers to functions on the XStormy16 are implemented
603
   by using 16 bit pointers, which are either direct pointers in case the
604
   function begins below 0x10000, or indirect pointers into a jump table.
605
   The next two functions convert 16 bit pointers into 24 (32) bit addresses
606
   and vice versa.  */
607
 
608
static CORE_ADDR
609
xstormy16_pointer_to_address (struct gdbarch *gdbarch,
610
                              struct type *type, const gdb_byte *buf)
611
{
612
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
613
  enum type_code target = TYPE_CODE (TYPE_TARGET_TYPE (type));
614
  CORE_ADDR addr
615
    = extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order);
616
 
617
  if (target == TYPE_CODE_FUNC || target == TYPE_CODE_METHOD)
618
    {
619
      CORE_ADDR addr2 = xstormy16_resolve_jmp_table_entry (gdbarch, addr);
620
      if (addr2)
621
        addr = addr2;
622
    }
623
 
624
  return addr;
625
}
626
 
627
static void
628
xstormy16_address_to_pointer (struct gdbarch *gdbarch,
629
                              struct type *type, gdb_byte *buf, CORE_ADDR addr)
630
{
631
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
632
  enum type_code target = TYPE_CODE (TYPE_TARGET_TYPE (type));
633
 
634
  if (target == TYPE_CODE_FUNC || target == TYPE_CODE_METHOD)
635
    {
636
      CORE_ADDR addr2 = xstormy16_find_jmp_table_entry (gdbarch, addr);
637
      if (addr2)
638
        addr = addr2;
639
    }
640
  store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order, addr);
641
}
642
 
643
static struct xstormy16_frame_cache *
644
xstormy16_alloc_frame_cache (void)
645
{
646
  struct xstormy16_frame_cache *cache;
647
  int i;
648
 
649
  cache = FRAME_OBSTACK_ZALLOC (struct xstormy16_frame_cache);
650
 
651
  cache->base = 0;
652
  cache->saved_sp = 0;
653
  cache->pc = 0;
654
  cache->uses_fp = 0;
655
  cache->framesize = 0;
656
  for (i = 0; i < E_NUM_REGS; ++i)
657
    cache->saved_regs[i] = REG_UNAVAIL;
658
 
659
  return cache;
660
}
661
 
662
static struct xstormy16_frame_cache *
663
xstormy16_frame_cache (struct frame_info *this_frame, void **this_cache)
664
{
665
  struct gdbarch *gdbarch = get_frame_arch (this_frame);
666
  struct xstormy16_frame_cache *cache;
667
  CORE_ADDR current_pc;
668
  int i;
669
 
670
  if (*this_cache)
671
    return *this_cache;
672
 
673
  cache = xstormy16_alloc_frame_cache ();
674
  *this_cache = cache;
675
 
676
  cache->base = get_frame_register_unsigned (this_frame, E_FP_REGNUM);
677
  if (cache->base == 0)
678
    return cache;
679
 
680
  cache->pc = get_frame_func (this_frame);
681
  current_pc = get_frame_pc (this_frame);
682
  if (cache->pc)
683
    xstormy16_analyze_prologue (gdbarch, cache->pc, current_pc,
684
                                cache, this_frame);
685
 
686
  if (!cache->uses_fp)
687
    cache->base = get_frame_register_unsigned (this_frame, E_SP_REGNUM);
688
 
689
  cache->saved_sp = cache->base - cache->framesize;
690
 
691
  for (i = 0; i < E_NUM_REGS; ++i)
692
    if (cache->saved_regs[i] != REG_UNAVAIL)
693
      cache->saved_regs[i] += cache->saved_sp;
694
 
695
  return cache;
696
}
697
 
698
static struct value *
699
xstormy16_frame_prev_register (struct frame_info *this_frame,
700
                               void **this_cache, int regnum)
701
{
702
  struct xstormy16_frame_cache *cache = xstormy16_frame_cache (this_frame,
703
                                                               this_cache);
704
  gdb_assert (regnum >= 0);
705
 
706
  if (regnum == E_SP_REGNUM && cache->saved_sp)
707
    return frame_unwind_got_constant (this_frame, regnum, cache->saved_sp);
708
 
709
  if (regnum < E_NUM_REGS && cache->saved_regs[regnum] != REG_UNAVAIL)
710
    return frame_unwind_got_memory (this_frame, regnum,
711
                                    cache->saved_regs[regnum]);
712
 
713
  return frame_unwind_got_register (this_frame, regnum, regnum);
714
}
715
 
716
static void
717
xstormy16_frame_this_id (struct frame_info *this_frame, void **this_cache,
718
                         struct frame_id *this_id)
719
{
720
  struct xstormy16_frame_cache *cache = xstormy16_frame_cache (this_frame,
721
                                                               this_cache);
722
 
723
  /* This marks the outermost frame.  */
724
  if (cache->base == 0)
725
    return;
726
 
727
  *this_id = frame_id_build (cache->saved_sp, cache->pc);
728
}
729
 
730
static CORE_ADDR
731
xstormy16_frame_base_address (struct frame_info *this_frame, void **this_cache)
732
{
733
  struct xstormy16_frame_cache *cache = xstormy16_frame_cache (this_frame,
734
                                                               this_cache);
735
  return cache->base;
736
}
737
 
738
static const struct frame_unwind xstormy16_frame_unwind = {
739
  NORMAL_FRAME,
740
  xstormy16_frame_this_id,
741
  xstormy16_frame_prev_register,
742
  NULL,
743
  default_frame_sniffer
744
};
745
 
746
static const struct frame_base xstormy16_frame_base = {
747
  &xstormy16_frame_unwind,
748
  xstormy16_frame_base_address,
749
  xstormy16_frame_base_address,
750
  xstormy16_frame_base_address
751
};
752
 
753
static CORE_ADDR
754
xstormy16_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
755
{
756
  return frame_unwind_register_unsigned (next_frame, E_SP_REGNUM);
757
}
758
 
759
static CORE_ADDR
760
xstormy16_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
761
{
762
  return frame_unwind_register_unsigned (next_frame, E_PC_REGNUM);
763
}
764
 
765
static struct frame_id
766
xstormy16_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
767
{
768
  CORE_ADDR sp = get_frame_register_unsigned (this_frame, E_SP_REGNUM);
769
  return frame_id_build (sp, get_frame_pc (this_frame));
770
}
771
 
772
 
773
/* Function: xstormy16_gdbarch_init
774
   Initializer function for the xstormy16 gdbarch vector.
775
   Called by gdbarch.  Sets up the gdbarch vector(s) for this target. */
776
 
777
static struct gdbarch *
778
xstormy16_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
779
{
780
  struct gdbarch *gdbarch;
781
 
782
  /* find a candidate among the list of pre-declared architectures. */
783
  arches = gdbarch_list_lookup_by_info (arches, &info);
784
  if (arches != NULL)
785
    return (arches->gdbarch);
786
 
787
  gdbarch = gdbarch_alloc (&info, NULL);
788
 
789
  /*
790
   * Basic register fields and methods, datatype sizes and stuff.
791
   */
792
 
793
  set_gdbarch_num_regs (gdbarch, E_NUM_REGS);
794
  set_gdbarch_num_pseudo_regs (gdbarch, 0);
795
  set_gdbarch_sp_regnum (gdbarch, E_SP_REGNUM);
796
  set_gdbarch_pc_regnum (gdbarch, E_PC_REGNUM);
797
  set_gdbarch_register_name (gdbarch, xstormy16_register_name);
798
  set_gdbarch_register_type (gdbarch, xstormy16_register_type);
799
 
800
  set_gdbarch_char_signed (gdbarch, 0);
801
  set_gdbarch_short_bit (gdbarch, 2 * TARGET_CHAR_BIT);
802
  set_gdbarch_int_bit (gdbarch, 2 * TARGET_CHAR_BIT);
803
  set_gdbarch_long_bit (gdbarch, 4 * TARGET_CHAR_BIT);
804
  set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT);
805
 
806
  set_gdbarch_float_bit (gdbarch, 4 * TARGET_CHAR_BIT);
807
  set_gdbarch_double_bit (gdbarch, 8 * TARGET_CHAR_BIT);
808
  set_gdbarch_long_double_bit (gdbarch, 8 * TARGET_CHAR_BIT);
809
 
810
  set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
811
  set_gdbarch_addr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
812
 
813
  set_gdbarch_address_to_pointer (gdbarch, xstormy16_address_to_pointer);
814
  set_gdbarch_pointer_to_address (gdbarch, xstormy16_pointer_to_address);
815
 
816
  /* Stack grows up. */
817
  set_gdbarch_inner_than (gdbarch, core_addr_greaterthan);
818
 
819
  /*
820
   * Frame Info
821
   */
822
  set_gdbarch_unwind_sp (gdbarch, xstormy16_unwind_sp);
823
  set_gdbarch_unwind_pc (gdbarch, xstormy16_unwind_pc);
824
  set_gdbarch_dummy_id (gdbarch, xstormy16_dummy_id);
825
  set_gdbarch_frame_align (gdbarch, xstormy16_frame_align);
826
  frame_base_set_default (gdbarch, &xstormy16_frame_base);
827
 
828
  set_gdbarch_skip_prologue (gdbarch, xstormy16_skip_prologue);
829
  set_gdbarch_in_function_epilogue_p (gdbarch,
830
                                      xstormy16_in_function_epilogue_p);
831
 
832
  /* These values and methods are used when gdb calls a target function.  */
833
  set_gdbarch_push_dummy_call (gdbarch, xstormy16_push_dummy_call);
834
  set_gdbarch_breakpoint_from_pc (gdbarch, xstormy16_breakpoint_from_pc);
835
  set_gdbarch_return_value (gdbarch, xstormy16_return_value);
836
 
837
  set_gdbarch_skip_trampoline_code (gdbarch, xstormy16_skip_trampoline_code);
838
 
839
  set_gdbarch_print_insn (gdbarch, print_insn_xstormy16);
840
 
841
  gdbarch_init_osabi (info, gdbarch);
842
 
843
  dwarf2_append_unwinders (gdbarch);
844
  frame_unwind_append_unwinder (gdbarch, &xstormy16_frame_unwind);
845
 
846
  return gdbarch;
847
}
848
 
849
/* Function: _initialize_xstormy16_tdep
850
   Initializer function for the Sanyo Xstormy16a module.
851
   Called by gdb at start-up. */
852
 
853
extern initialize_file_ftype _initialize_xstormy16_tdep; /* -Wmissing-prototypes */
854
 
855
void
856
_initialize_xstormy16_tdep (void)
857
{
858
  register_gdbarch_init (bfd_arch_xstormy16, xstormy16_gdbarch_init);
859
}

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