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

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-stable/] [gdb-7.2/] [gdb/] [rx-tdep.c] - Blame information for rev 841

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 330 jeremybenn
/* Target-dependent code for the Renesas RX for GDB, the GNU debugger.
2
 
3
   Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
4
 
5
   Contributed by Red Hat, Inc.
6
 
7
   This file is part of GDB.
8
 
9
   This program is free software; you can redistribute it and/or modify
10
   it under the terms of the GNU General Public License as published by
11
   the Free Software Foundation; either version 3 of the License, or
12
   (at your option) any later version.
13
 
14
   This program is distributed in the hope that it will be useful,
15
   but WITHOUT ANY WARRANTY; without even the implied warranty of
16
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17
   GNU General Public License for more details.
18
 
19
   You should have received a copy of the GNU General Public License
20
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
21
 
22
#include "defs.h"
23
#include "arch-utils.h"
24
#include "prologue-value.h"
25
#include "target.h"
26
#include "regcache.h"
27
#include "opcode/rx.h"
28
#include "dis-asm.h"
29
#include "gdbtypes.h"
30
#include "frame.h"
31
#include "frame-unwind.h"
32
#include "frame-base.h"
33
#include "value.h"
34
#include "gdbcore.h"
35
#include "dwarf2-frame.h"
36
 
37
#include "elf/rx.h"
38
#include "elf-bfd.h"
39
 
40
/* Certain important register numbers.  */
41
enum
42
{
43
  RX_SP_REGNUM = 0,
44
  RX_R1_REGNUM = 1,
45
  RX_R4_REGNUM = 4,
46
  RX_FP_REGNUM = 6,
47
  RX_R15_REGNUM = 15,
48
  RX_PC_REGNUM = 19,
49
  RX_ACC_REGNUM = 25,
50
  RX_NUM_REGS = 26
51
};
52
 
53
/* Architecture specific data.  */
54
struct gdbarch_tdep
55
{
56
  /* The ELF header flags specify the multilib used.  */
57
  int elf_flags;
58
};
59
 
60
/* This structure holds the results of a prologue analysis.  */
61
struct rx_prologue
62
{
63
  /* The offset from the frame base to the stack pointer --- always
64
     zero or negative.
65
 
66
     Calling this a "size" is a bit misleading, but given that the
67
     stack grows downwards, using offsets for everything keeps one
68
     from going completely sign-crazy: you never change anything's
69
     sign for an ADD instruction; always change the second operand's
70
     sign for a SUB instruction; and everything takes care of
71
     itself.  */
72
  int frame_size;
73
 
74
  /* Non-zero if this function has initialized the frame pointer from
75
     the stack pointer, zero otherwise.  */
76
  int has_frame_ptr;
77
 
78
  /* If has_frame_ptr is non-zero, this is the offset from the frame
79
     base to where the frame pointer points.  This is always zero or
80
     negative.  */
81
  int frame_ptr_offset;
82
 
83
  /* The address of the first instruction at which the frame has been
84
     set up and the arguments are where the debug info says they are
85
     --- as best as we can tell.  */
86
  CORE_ADDR prologue_end;
87
 
88
  /* reg_offset[R] is the offset from the CFA at which register R is
89
     saved, or 1 if register R has not been saved.  (Real values are
90
     always zero or negative.)  */
91
  int reg_offset[RX_NUM_REGS];
92
};
93
 
94
/* Implement the "register_name" gdbarch method.  */
95
static const char *
96
rx_register_name (struct gdbarch *gdbarch, int regnr)
97
{
98
  static const char *const reg_names[] = {
99
    "r0",
100
    "r1",
101
    "r2",
102
    "r3",
103
    "r4",
104
    "r5",
105
    "r6",
106
    "r7",
107
    "r8",
108
    "r9",
109
    "r10",
110
    "r11",
111
    "r12",
112
    "r13",
113
    "r14",
114
    "r15",
115
    "usp",
116
    "isp",
117
    "psw",
118
    "pc",
119
    "intb",
120
    "bpsw",
121
    "bpc",
122
    "fintv",
123
    "fpsw",
124
    "acc"
125
  };
126
 
127
  return reg_names[regnr];
128
}
129
 
130
/* Implement the "register_type" gdbarch method.  */
131
static struct type *
132
rx_register_type (struct gdbarch *gdbarch, int reg_nr)
133
{
134
  if (reg_nr == RX_PC_REGNUM)
135
    return builtin_type (gdbarch)->builtin_func_ptr;
136
  else if (reg_nr == RX_ACC_REGNUM)
137
    return builtin_type (gdbarch)->builtin_unsigned_long_long;
138
  else
139
    return builtin_type (gdbarch)->builtin_unsigned_long;
140
}
141
 
142
 
143
/* Function for finding saved registers in a 'struct pv_area'; this
144
   function is passed to pv_area_scan.
145
 
146
   If VALUE is a saved register, ADDR says it was saved at a constant
147
   offset from the frame base, and SIZE indicates that the whole
148
   register was saved, record its offset.  */
149
static void
150
check_for_saved (void *result_untyped, pv_t addr, CORE_ADDR size, pv_t value)
151
{
152
  struct rx_prologue *result = (struct rx_prologue *) result_untyped;
153
 
154
  if (value.kind == pvk_register
155
      && value.k == 0
156
      && pv_is_register (addr, RX_SP_REGNUM)
157
      && size == register_size (target_gdbarch, value.reg))
158
    result->reg_offset[value.reg] = addr.k;
159
}
160
 
161
/* Define a "handle" struct for fetching the next opcode.  */
162
struct rx_get_opcode_byte_handle
163
{
164
  CORE_ADDR pc;
165
};
166
 
167
/* Fetch a byte on behalf of the opcode decoder.  HANDLE contains
168
   the memory address of the next byte to fetch.  If successful,
169
   the address in the handle is updated and the byte fetched is
170
   returned as the value of the function.  If not successful, -1
171
   is returned.  */
172
static int
173
rx_get_opcode_byte (void *handle)
174
{
175
  struct rx_get_opcode_byte_handle *opcdata = handle;
176
  int status;
177
  gdb_byte byte;
178
 
179
  status = target_read_memory (opcdata->pc, &byte, 1);
180
  if (status == 0)
181
    {
182
      opcdata->pc += 1;
183
      return byte;
184
    }
185
  else
186
    return -1;
187
}
188
 
189
/* Analyze a prologue starting at START_PC, going no further than
190
   LIMIT_PC.  Fill in RESULT as appropriate.  */
191
static void
192
rx_analyze_prologue (CORE_ADDR start_pc,
193
                     CORE_ADDR limit_pc, struct rx_prologue *result)
194
{
195
  CORE_ADDR pc, next_pc;
196
  int rn;
197
  pv_t reg[RX_NUM_REGS];
198
  struct pv_area *stack;
199
  struct cleanup *back_to;
200
  CORE_ADDR after_last_frame_setup_insn = start_pc;
201
 
202
  memset (result, 0, sizeof (*result));
203
 
204
  for (rn = 0; rn < RX_NUM_REGS; rn++)
205
    {
206
      reg[rn] = pv_register (rn, 0);
207
      result->reg_offset[rn] = 1;
208
    }
209
 
210
  stack = make_pv_area (RX_SP_REGNUM, gdbarch_addr_bit (target_gdbarch));
211
  back_to = make_cleanup_free_pv_area (stack);
212
 
213
  /* The call instruction has saved the return address on the stack.  */
214
  reg[RX_SP_REGNUM] = pv_add_constant (reg[RX_SP_REGNUM], -4);
215
  pv_area_store (stack, reg[RX_SP_REGNUM], 4, reg[RX_PC_REGNUM]);
216
 
217
  pc = start_pc;
218
  while (pc < limit_pc)
219
    {
220
      int bytes_read;
221
      struct rx_get_opcode_byte_handle opcode_handle;
222
      RX_Opcode_Decoded opc;
223
 
224
      opcode_handle.pc = pc;
225
      bytes_read = rx_decode_opcode (pc, &opc, rx_get_opcode_byte,
226
                                     &opcode_handle);
227
      next_pc = pc + bytes_read;
228
 
229
      if (opc.id == RXO_pushm   /* pushm r1, r2 */
230
          && opc.op[1].type == RX_Operand_Register
231
          && opc.op[2].type == RX_Operand_Register)
232
        {
233
          int r1, r2;
234
          int r;
235
 
236
          r1 = opc.op[1].reg;
237
          r2 = opc.op[2].reg;
238
          for (r = r2; r >= r1; r--)
239
            {
240
              reg[RX_SP_REGNUM] = pv_add_constant (reg[RX_SP_REGNUM], -4);
241
              pv_area_store (stack, reg[RX_SP_REGNUM], 4, reg[r]);
242
            }
243
          after_last_frame_setup_insn = next_pc;
244
        }
245
      else if (opc.id == RXO_mov        /* mov.l rdst, rsrc */
246
               && opc.op[0].type == RX_Operand_Register
247
               && opc.op[1].type == RX_Operand_Register
248
               && opc.size == RX_Long)
249
        {
250
          int rdst, rsrc;
251
 
252
          rdst = opc.op[0].reg;
253
          rsrc = opc.op[1].reg;
254
          reg[rdst] = reg[rsrc];
255
          if (rdst == RX_FP_REGNUM && rsrc == RX_SP_REGNUM)
256
            after_last_frame_setup_insn = next_pc;
257
        }
258
      else if (opc.id == RXO_mov        /* mov.l rsrc, [-SP] */
259
               && opc.op[0].type == RX_Operand_Predec
260
               && opc.op[0].reg == RX_SP_REGNUM
261
               && opc.op[1].type == RX_Operand_Register
262
               && opc.size == RX_Long)
263
        {
264
          int rsrc;
265
 
266
          rsrc = opc.op[1].reg;
267
          reg[RX_SP_REGNUM] = pv_add_constant (reg[RX_SP_REGNUM], -4);
268
          pv_area_store (stack, reg[RX_SP_REGNUM], 4, reg[rsrc]);
269
          after_last_frame_setup_insn = next_pc;
270
        }
271
      else if (opc.id == RXO_add        /* add #const, rsrc, rdst */
272
               && opc.op[0].type == RX_Operand_Register
273
               && opc.op[1].type == RX_Operand_Immediate
274
               && opc.op[2].type == RX_Operand_Register)
275
        {
276
          int rdst = opc.op[0].reg;
277
          int addend = opc.op[1].addend;
278
          int rsrc = opc.op[2].reg;
279
          reg[rdst] = pv_add_constant (reg[rsrc], addend);
280
          /* Negative adjustments to the stack pointer or frame pointer
281
             are (most likely) part of the prologue.  */
282
          if ((rdst == RX_SP_REGNUM || rdst == RX_FP_REGNUM) && addend < 0)
283
            after_last_frame_setup_insn = next_pc;
284
        }
285
      else if (opc.id == RXO_mov
286
               && opc.op[0].type == RX_Operand_Indirect
287
               && opc.op[1].type == RX_Operand_Register
288
               && opc.size == RX_Long
289
               && (opc.op[0].reg == RX_SP_REGNUM
290
                   || opc.op[0].reg == RX_FP_REGNUM)
291
               && (RX_R1_REGNUM <= opc.op[1].reg
292
                   && opc.op[1].reg <= RX_R4_REGNUM))
293
        {
294
          /* This moves an argument register to the stack.  Don't
295
             record it, but allow it to be a part of the prologue.  */
296
        }
297
      else if (opc.id == RXO_branch
298
               && opc.op[0].type == RX_Operand_Immediate
299
               && opc.op[1].type == RX_Operand_Condition
300
               && next_pc < opc.op[0].addend)
301
        {
302
          /* When a loop appears as the first statement of a function
303
             body, gcc 4.x will use a BRA instruction to branch to the
304
             loop condition checking code.  This BRA instruction is
305
             marked as part of the prologue.  We therefore set next_pc
306
             to this branch target and also stop the prologue scan.
307
             The instructions at and beyond the branch target should
308
             no longer be associated with the prologue.
309
 
310
             Note that we only consider forward branches here.  We
311
             presume that a forward branch is being used to skip over
312
             a loop body.
313
 
314
             A backwards branch is covered by the default case below.
315
             If we were to encounter a backwards branch, that would
316
             most likely mean that we've scanned through a loop body.
317
             We definitely want to stop the prologue scan when this
318
             happens and that is precisely what is done by the default
319
             case below.  */
320
 
321
          after_last_frame_setup_insn = opc.op[0].addend;
322
          break;                /* Scan no further if we hit this case.  */
323
        }
324
      else
325
        {
326
          /* Terminate the prologue scan.  */
327
          break;
328
        }
329
 
330
      pc = next_pc;
331
    }
332
 
333
  /* Is the frame size (offset, really) a known constant?  */
334
  if (pv_is_register (reg[RX_SP_REGNUM], RX_SP_REGNUM))
335
    result->frame_size = reg[RX_SP_REGNUM].k;
336
 
337
  /* Was the frame pointer initialized?  */
338
  if (pv_is_register (reg[RX_FP_REGNUM], RX_SP_REGNUM))
339
    {
340
      result->has_frame_ptr = 1;
341
      result->frame_ptr_offset = reg[RX_FP_REGNUM].k;
342
    }
343
 
344
  /* Record where all the registers were saved.  */
345
  pv_area_scan (stack, check_for_saved, (void *) result);
346
 
347
  result->prologue_end = after_last_frame_setup_insn;
348
 
349
  do_cleanups (back_to);
350
}
351
 
352
 
353
/* Implement the "skip_prologue" gdbarch method.  */
354
static CORE_ADDR
355
rx_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
356
{
357
  char *name;
358
  CORE_ADDR func_addr, func_end;
359
  struct rx_prologue p;
360
 
361
  /* Try to find the extent of the function that contains PC.  */
362
  if (!find_pc_partial_function (pc, &name, &func_addr, &func_end))
363
    return pc;
364
 
365
  rx_analyze_prologue (pc, func_end, &p);
366
  return p.prologue_end;
367
}
368
 
369
/* Given a frame described by THIS_FRAME, decode the prologue of its
370
   associated function if there is not cache entry as specified by
371
   THIS_PROLOGUE_CACHE.  Save the decoded prologue in the cache and
372
   return that struct as the value of this function.  */
373
static struct rx_prologue *
374
rx_analyze_frame_prologue (struct frame_info *this_frame,
375
                           void **this_prologue_cache)
376
{
377
  if (!*this_prologue_cache)
378
    {
379
      CORE_ADDR func_start, stop_addr;
380
 
381
      *this_prologue_cache = FRAME_OBSTACK_ZALLOC (struct rx_prologue);
382
 
383
      func_start = get_frame_func (this_frame);
384
      stop_addr = get_frame_pc (this_frame);
385
 
386
      /* If we couldn't find any function containing the PC, then
387
         just initialize the prologue cache, but don't do anything.  */
388
      if (!func_start)
389
        stop_addr = func_start;
390
 
391
      rx_analyze_prologue (func_start, stop_addr, *this_prologue_cache);
392
    }
393
 
394
  return *this_prologue_cache;
395
}
396
 
397
/* Given the next frame and a prologue cache, return this frame's
398
   base.  */
399
static CORE_ADDR
400
rx_frame_base (struct frame_info *this_frame, void **this_prologue_cache)
401
{
402
  struct rx_prologue *p
403
    = rx_analyze_frame_prologue (this_frame, this_prologue_cache);
404
 
405
  /* In functions that use alloca, the distance between the stack
406
     pointer and the frame base varies dynamically, so we can't use
407
     the SP plus static information like prologue analysis to find the
408
     frame base.  However, such functions must have a frame pointer,
409
     to be able to restore the SP on exit.  So whenever we do have a
410
     frame pointer, use that to find the base.  */
411
  if (p->has_frame_ptr)
412
    {
413
      CORE_ADDR fp = get_frame_register_unsigned (this_frame, RX_FP_REGNUM);
414
      return fp - p->frame_ptr_offset;
415
    }
416
  else
417
    {
418
      CORE_ADDR sp = get_frame_register_unsigned (this_frame, RX_SP_REGNUM);
419
      return sp - p->frame_size;
420
    }
421
}
422
 
423
/* Implement the "frame_this_id" method for unwinding frames.  */
424
static void
425
rx_frame_this_id (struct frame_info *this_frame,
426
                  void **this_prologue_cache, struct frame_id *this_id)
427
{
428
  *this_id = frame_id_build (rx_frame_base (this_frame, this_prologue_cache),
429
                             get_frame_func (this_frame));
430
}
431
 
432
/* Implement the "frame_prev_register" method for unwinding frames.  */
433
static struct value *
434
rx_frame_prev_register (struct frame_info *this_frame,
435
                        void **this_prologue_cache, int regnum)
436
{
437
  struct rx_prologue *p
438
    = rx_analyze_frame_prologue (this_frame, this_prologue_cache);
439
  CORE_ADDR frame_base = rx_frame_base (this_frame, this_prologue_cache);
440
  int reg_size = register_size (get_frame_arch (this_frame), regnum);
441
 
442
  if (regnum == RX_SP_REGNUM)
443
    return frame_unwind_got_constant (this_frame, regnum, frame_base);
444
 
445
  /* If prologue analysis says we saved this register somewhere,
446
     return a description of the stack slot holding it.  */
447
  else if (p->reg_offset[regnum] != 1)
448
    return frame_unwind_got_memory (this_frame, regnum,
449
                                    frame_base + p->reg_offset[regnum]);
450
 
451
  /* Otherwise, presume we haven't changed the value of this
452
     register, and get it from the next frame.  */
453
  else
454
    return frame_unwind_got_register (this_frame, regnum, regnum);
455
}
456
 
457
static const struct frame_unwind rx_frame_unwind = {
458
  NORMAL_FRAME,
459
  rx_frame_this_id,
460
  rx_frame_prev_register,
461
  NULL,
462
  default_frame_sniffer
463
};
464
 
465
/* Implement the "unwind_pc" gdbarch method.  */
466
static CORE_ADDR
467
rx_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
468
{
469
  ULONGEST pc;
470
 
471
  pc = frame_unwind_register_unsigned (this_frame, RX_PC_REGNUM);
472
  return pc;
473
}
474
 
475
/* Implement the "unwind_sp" gdbarch method.  */
476
static CORE_ADDR
477
rx_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
478
{
479
  ULONGEST sp;
480
 
481
  sp = frame_unwind_register_unsigned (this_frame, RX_SP_REGNUM);
482
  return sp;
483
}
484
 
485
/* Implement the "dummy_id" gdbarch method.  */
486
static struct frame_id
487
rx_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
488
{
489
  return
490
    frame_id_build (get_frame_register_unsigned (this_frame, RX_SP_REGNUM),
491
                    get_frame_pc (this_frame));
492
}
493
 
494
/* Implement the "push_dummy_call" gdbarch method.  */
495
static CORE_ADDR
496
rx_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
497
                    struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
498
                    struct value **args, CORE_ADDR sp, int struct_return,
499
                    CORE_ADDR struct_addr)
500
{
501
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
502
  int write_pass;
503
  int sp_off = 0;
504
  CORE_ADDR cfa;
505
  int num_register_candidate_args;
506
 
507
  struct type *func_type = value_type (function);
508
 
509
  /* Dereference function pointer types.  */
510
  while (TYPE_CODE (func_type) == TYPE_CODE_PTR)
511
    func_type = TYPE_TARGET_TYPE (func_type);
512
 
513
  /* The end result had better be a function or a method.  */
514
  gdb_assert (TYPE_CODE (func_type) == TYPE_CODE_FUNC
515
              || TYPE_CODE (func_type) == TYPE_CODE_METHOD);
516
 
517
  /* Functions with a variable number of arguments have all of their
518
     variable arguments and the last non-variable argument passed
519
     on the stack.
520
 
521
     Otherwise, we can pass up to four arguments on the stack.
522
 
523
     Once computed, we leave this value alone.  I.e. we don't update
524
     it in case of a struct return going in a register or an argument
525
     requiring multiple registers, etc.  We rely instead on the value
526
     of the ``arg_reg'' variable to get these other details correct.  */
527
 
528
  if (TYPE_VARARGS (func_type))
529
    num_register_candidate_args = TYPE_NFIELDS (func_type) - 1;
530
  else
531
    num_register_candidate_args = 4;
532
 
533
  /* We make two passes; the first does the stack allocation,
534
     the second actually stores the arguments.  */
535
  for (write_pass = 0; write_pass <= 1; write_pass++)
536
    {
537
      int i;
538
      int arg_reg = RX_R1_REGNUM;
539
 
540
      if (write_pass)
541
        sp = align_down (sp - sp_off, 4);
542
      sp_off = 0;
543
 
544
      if (struct_return)
545
        {
546
          struct type *return_type = TYPE_TARGET_TYPE (func_type);
547
 
548
          gdb_assert (TYPE_CODE (return_type) == TYPE_CODE_STRUCT
549
                      || TYPE_CODE (func_type) == TYPE_CODE_UNION);
550
 
551
          if (TYPE_LENGTH (return_type) > 16
552
              || TYPE_LENGTH (return_type) % 4 != 0)
553
            {
554
              if (write_pass)
555
                regcache_cooked_write_unsigned (regcache, RX_R15_REGNUM,
556
                                                struct_addr);
557
            }
558
        }
559
 
560
      /* Push the arguments.  */
561
      for (i = 0; i < nargs; i++)
562
        {
563
          struct value *arg = args[i];
564
          const gdb_byte *arg_bits = value_contents_all (arg);
565
          struct type *arg_type = check_typedef (value_type (arg));
566
          ULONGEST arg_size = TYPE_LENGTH (arg_type);
567
 
568
          if (i == 0 && struct_addr != 0 && !struct_return
569
              && TYPE_CODE (arg_type) == TYPE_CODE_PTR
570
              && extract_unsigned_integer (arg_bits, 4,
571
                                           byte_order) == struct_addr)
572
            {
573
              /* This argument represents the address at which C++ (and
574
                 possibly other languages) store their return value.
575
                 Put this value in R15.  */
576
              if (write_pass)
577
                regcache_cooked_write_unsigned (regcache, RX_R15_REGNUM,
578
                                                struct_addr);
579
            }
580
          else if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT
581
                   && TYPE_CODE (arg_type) != TYPE_CODE_UNION)
582
            {
583
              /* Argument is a scalar.  */
584
              if (arg_size == 8)
585
                {
586
                  if (i < num_register_candidate_args
587
                      && arg_reg <= RX_R4_REGNUM - 1)
588
                    {
589
                      /* If argument registers are going to be used to pass
590
                         an 8 byte scalar, the ABI specifies that two registers
591
                         must be available.  */
592
                      if (write_pass)
593
                        {
594
                          regcache_cooked_write_unsigned (regcache, arg_reg,
595
                                                          extract_unsigned_integer
596
                                                          (arg_bits, 4,
597
                                                           byte_order));
598
                          regcache_cooked_write_unsigned (regcache,
599
                                                          arg_reg + 1,
600
                                                          extract_unsigned_integer
601
                                                          (arg_bits + 4, 4,
602
                                                           byte_order));
603
                        }
604
                      arg_reg += 2;
605
                    }
606
                  else
607
                    {
608
                      sp_off = align_up (sp_off, 4);
609
                      /* Otherwise, pass the 8 byte scalar on the stack.  */
610
                      if (write_pass)
611
                        write_memory (sp + sp_off, arg_bits, 8);
612
                      sp_off += 8;
613
                    }
614
                }
615
              else
616
                {
617
                  ULONGEST u;
618
 
619
                  gdb_assert (arg_size <= 4);
620
 
621
                  u =
622
                    extract_unsigned_integer (arg_bits, arg_size, byte_order);
623
 
624
                  if (i < num_register_candidate_args
625
                      && arg_reg <= RX_R4_REGNUM)
626
                    {
627
                      if (write_pass)
628
                        regcache_cooked_write_unsigned (regcache, arg_reg, u);
629
                      arg_reg += 1;
630
                    }
631
                  else
632
                    {
633
                      int p_arg_size = 4;
634
 
635
                      if (TYPE_PROTOTYPED (func_type)
636
                          && i < TYPE_NFIELDS (func_type))
637
                        {
638
                          struct type *p_arg_type =
639
                            TYPE_FIELD_TYPE (func_type, i);
640
                          p_arg_size = TYPE_LENGTH (p_arg_type);
641
                        }
642
 
643
                      sp_off = align_up (sp_off, p_arg_size);
644
 
645
                      if (write_pass)
646
                        write_memory_unsigned_integer (sp + sp_off,
647
                                                       p_arg_size, byte_order,
648
                                                       u);
649
                      sp_off += p_arg_size;
650
                    }
651
                }
652
            }
653
          else
654
            {
655
              /* Argument is a struct or union.  Pass as much of the struct
656
                 in registers, if possible.  Pass the rest on the stack.  */
657
              while (arg_size > 0)
658
                {
659
                  if (i < num_register_candidate_args
660
                      && arg_reg <= RX_R4_REGNUM
661
                      && arg_size <= 4 * (RX_R4_REGNUM - arg_reg + 1)
662
                      && arg_size % 4 == 0)
663
                    {
664
                      int len = min (arg_size, 4);
665
 
666
                      if (write_pass)
667
                        regcache_cooked_write_unsigned (regcache, arg_reg,
668
                                                        extract_unsigned_integer
669
                                                        (arg_bits, len,
670
                                                         byte_order));
671
                      arg_bits += len;
672
                      arg_size -= len;
673
                      arg_reg++;
674
                    }
675
                  else
676
                    {
677
                      sp_off = align_up (sp_off, 4);
678
                      if (write_pass)
679
                        write_memory (sp + sp_off, arg_bits, arg_size);
680
                      sp_off += align_up (arg_size, 4);
681
                      arg_size = 0;
682
                    }
683
                }
684
            }
685
        }
686
    }
687
 
688
  /* Keep track of the stack address prior to pushing the return address.
689
     This is the value that we'll return.  */
690
  cfa = sp;
691
 
692
  /* Push the return address.  */
693
  sp = sp - 4;
694
  write_memory_unsigned_integer (sp, 4, byte_order, bp_addr);
695
 
696
  /* Update the stack pointer.  */
697
  regcache_cooked_write_unsigned (regcache, RX_SP_REGNUM, sp);
698
 
699
  return cfa;
700
}
701
 
702
/* Implement the "return_value" gdbarch method.  */
703
static enum return_value_convention
704
rx_return_value (struct gdbarch *gdbarch,
705
                 struct type *func_type,
706
                 struct type *valtype,
707
                 struct regcache *regcache,
708
                 gdb_byte *readbuf, const gdb_byte *writebuf)
709
{
710
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
711
  ULONGEST valtype_len = TYPE_LENGTH (valtype);
712
 
713
  if (TYPE_LENGTH (valtype) > 16
714
      || ((TYPE_CODE (valtype) == TYPE_CODE_STRUCT
715
           || TYPE_CODE (valtype) == TYPE_CODE_UNION)
716
          && TYPE_LENGTH (valtype) % 4 != 0))
717
    return RETURN_VALUE_STRUCT_CONVENTION;
718
 
719
  if (readbuf)
720
    {
721
      ULONGEST u;
722
      int argreg = RX_R1_REGNUM;
723
      int offset = 0;
724
 
725
      while (valtype_len > 0)
726
        {
727
          int len = min (valtype_len, 4);
728
 
729
          regcache_cooked_read_unsigned (regcache, argreg, &u);
730
          store_unsigned_integer (readbuf + offset, len, byte_order, u);
731
          valtype_len -= len;
732
          offset += len;
733
          argreg++;
734
        }
735
    }
736
 
737
  if (writebuf)
738
    {
739
      ULONGEST u;
740
      int argreg = RX_R1_REGNUM;
741
      int offset = 0;
742
 
743
      while (valtype_len > 0)
744
        {
745
          int len = min (valtype_len, 4);
746
 
747
          u = extract_unsigned_integer (writebuf + offset, len, byte_order);
748
          regcache_cooked_write_unsigned (regcache, argreg, u);
749
          valtype_len -= len;
750
          offset += len;
751
          argreg++;
752
        }
753
    }
754
 
755
  return RETURN_VALUE_REGISTER_CONVENTION;
756
}
757
 
758
/* Implement the "breakpoint_from_pc" gdbarch method.  */
759
const gdb_byte *
760
rx_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr, int *lenptr)
761
{
762
  static gdb_byte breakpoint[] = { 0x00 };
763
  *lenptr = sizeof breakpoint;
764
  return breakpoint;
765
}
766
 
767
/* Allocate and initialize a gdbarch object.  */
768
static struct gdbarch *
769
rx_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
770
{
771
  struct gdbarch *gdbarch;
772
  struct gdbarch_tdep *tdep;
773
  int elf_flags;
774
 
775
  /* Extract the elf_flags if available.  */
776
  if (info.abfd != NULL
777
      && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour)
778
    elf_flags = elf_elfheader (info.abfd)->e_flags;
779
  else
780
    elf_flags = 0;
781
 
782
 
783
  /* Try to find the architecture in the list of already defined
784
     architectures.  */
785
  for (arches = gdbarch_list_lookup_by_info (arches, &info);
786
       arches != NULL;
787
       arches = gdbarch_list_lookup_by_info (arches->next, &info))
788
    {
789
      if (gdbarch_tdep (arches->gdbarch)->elf_flags != elf_flags)
790
        continue;
791
 
792
      return arches->gdbarch;
793
    }
794
 
795
  /* None found, create a new architecture from the information
796
     provided.  */
797
  tdep = (struct gdbarch_tdep *) xmalloc (sizeof (struct gdbarch_tdep));
798
  gdbarch = gdbarch_alloc (&info, tdep);
799
  tdep->elf_flags = elf_flags;
800
 
801
  set_gdbarch_num_regs (gdbarch, RX_NUM_REGS);
802
  set_gdbarch_num_pseudo_regs (gdbarch, 0);
803
  set_gdbarch_register_name (gdbarch, rx_register_name);
804
  set_gdbarch_register_type (gdbarch, rx_register_type);
805
  set_gdbarch_pc_regnum (gdbarch, RX_PC_REGNUM);
806
  set_gdbarch_sp_regnum (gdbarch, RX_SP_REGNUM);
807
  set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
808
  set_gdbarch_decr_pc_after_break (gdbarch, 1);
809
  set_gdbarch_breakpoint_from_pc (gdbarch, rx_breakpoint_from_pc);
810
  set_gdbarch_skip_prologue (gdbarch, rx_skip_prologue);
811
 
812
  set_gdbarch_print_insn (gdbarch, print_insn_rx);
813
 
814
  set_gdbarch_unwind_pc (gdbarch, rx_unwind_pc);
815
  set_gdbarch_unwind_sp (gdbarch, rx_unwind_sp);
816
 
817
  /* Target builtin data types.  */
818
  set_gdbarch_char_signed (gdbarch, 0);
819
  set_gdbarch_short_bit (gdbarch, 16);
820
  set_gdbarch_int_bit (gdbarch, 32);
821
  set_gdbarch_long_bit (gdbarch, 32);
822
  set_gdbarch_long_long_bit (gdbarch, 64);
823
  set_gdbarch_ptr_bit (gdbarch, 32);
824
  set_gdbarch_float_bit (gdbarch, 32);
825
  set_gdbarch_float_format (gdbarch, floatformats_ieee_single);
826
  if (elf_flags & E_FLAG_RX_64BIT_DOUBLES)
827
    {
828
      set_gdbarch_double_bit (gdbarch, 64);
829
      set_gdbarch_long_double_bit (gdbarch, 64);
830
      set_gdbarch_double_format (gdbarch, floatformats_ieee_double);
831
      set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double);
832
    }
833
  else
834
    {
835
      set_gdbarch_double_bit (gdbarch, 32);
836
      set_gdbarch_long_double_bit (gdbarch, 32);
837
      set_gdbarch_double_format (gdbarch, floatformats_ieee_single);
838
      set_gdbarch_long_double_format (gdbarch, floatformats_ieee_single);
839
    }
840
 
841
  /* Frame unwinding.  */
842
#if 0
843
  /* Note: The test results are better with the dwarf2 unwinder disabled,
844
     so it's turned off for now.  */
845
  dwarf2_append_unwinders (gdbarch);
846
#endif
847
  frame_unwind_append_unwinder (gdbarch, &rx_frame_unwind);
848
 
849
  /* Methods for saving / extracting a dummy frame's ID.
850
     The ID's stack address must match the SP value returned by
851
     PUSH_DUMMY_CALL, and saved by generic_save_dummy_frame_tos.  */
852
  set_gdbarch_dummy_id (gdbarch, rx_dummy_id);
853
  set_gdbarch_push_dummy_call (gdbarch, rx_push_dummy_call);
854
  set_gdbarch_return_value (gdbarch, rx_return_value);
855
 
856
  /* Virtual tables.  */
857
  set_gdbarch_vbit_in_delta (gdbarch, 1);
858
 
859
  return gdbarch;
860
}
861
 
862
/* Register the above initialization routine.  */
863
void
864
_initialize_rx_tdep (void)
865
{
866
  register_gdbarch_init (bfd_arch_rx, rx_gdbarch_init);
867
}

powered by: WebSVN 2.1.0

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