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

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [gdb-7.1/] [gdb/] [sparc-tdep.c] - Blame information for rev 855

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

Line No. Rev Author Line
1 227 jeremybenn
/* Target-dependent code for SPARC.
2
 
3
   Copyright (C) 2003, 2004, 2005, 2006, 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 "arch-utils.h"
23
#include "dis-asm.h"
24
#include "dwarf2-frame.h"
25
#include "floatformat.h"
26
#include "frame.h"
27
#include "frame-base.h"
28
#include "frame-unwind.h"
29
#include "gdbcore.h"
30
#include "gdbtypes.h"
31
#include "inferior.h"
32
#include "symtab.h"
33
#include "objfiles.h"
34
#include "osabi.h"
35
#include "regcache.h"
36
#include "target.h"
37
#include "value.h"
38
 
39
#include "gdb_assert.h"
40
#include "gdb_string.h"
41
 
42
#include "sparc-tdep.h"
43
 
44
struct regset;
45
 
46
/* This file implements the SPARC 32-bit ABI as defined by the section
47
   "Low-Level System Information" of the SPARC Compliance Definition
48
   (SCD) 2.4.1, which is the 32-bit System V psABI for SPARC.  The SCD
49
   lists changes with respect to the original 32-bit psABI as defined
50
   in the "System V ABI, SPARC Processor Supplement".
51
 
52
   Note that if we talk about SunOS, we mean SunOS 4.x, which was
53
   BSD-based, which is sometimes (retroactively?) referred to as
54
   Solaris 1.x.  If we talk about Solaris we mean Solaris 2.x and
55
   above (Solaris 7, 8 and 9 are nothing but Solaris 2.7, 2.8 and 2.9
56
   suffering from severe version number inflation).  Solaris 2.x is
57
   also known as SunOS 5.x, since that's what uname(1) says.  Solaris
58
   2.x is SVR4-based.  */
59
 
60
/* Please use the sparc32_-prefix for 32-bit specific code, the
61
   sparc64_-prefix for 64-bit specific code and the sparc_-prefix for
62
   code that can handle both.  The 64-bit specific code lives in
63
   sparc64-tdep.c; don't add any here.  */
64
 
65
/* The SPARC Floating-Point Quad-Precision format is similar to
66
   big-endian IA-64 Quad-recision format.  */
67
#define floatformats_sparc_quad floatformats_ia64_quad
68
 
69
/* The stack pointer is offset from the stack frame by a BIAS of 2047
70
   (0x7ff) for 64-bit code.  BIAS is likely to be defined on SPARC
71
   hosts, so undefine it first.  */
72
#undef BIAS
73
#define BIAS 2047
74
 
75
/* Macros to extract fields from SPARC instructions.  */
76
#define X_OP(i) (((i) >> 30) & 0x3)
77
#define X_RD(i) (((i) >> 25) & 0x1f)
78
#define X_A(i) (((i) >> 29) & 1)
79
#define X_COND(i) (((i) >> 25) & 0xf)
80
#define X_OP2(i) (((i) >> 22) & 0x7)
81
#define X_IMM22(i) ((i) & 0x3fffff)
82
#define X_OP3(i) (((i) >> 19) & 0x3f)
83
#define X_RS1(i) (((i) >> 14) & 0x1f)
84
#define X_RS2(i) ((i) & 0x1f)
85
#define X_I(i) (((i) >> 13) & 1)
86
/* Sign extension macros.  */
87
#define X_DISP22(i) ((X_IMM22 (i) ^ 0x200000) - 0x200000)
88
#define X_DISP19(i) ((((i) & 0x7ffff) ^ 0x40000) - 0x40000)
89
#define X_SIMM13(i) ((((i) & 0x1fff) ^ 0x1000) - 0x1000)
90
 
91
/* Fetch the instruction at PC.  Instructions are always big-endian
92
   even if the processor operates in little-endian mode.  */
93
 
94
unsigned long
95
sparc_fetch_instruction (CORE_ADDR pc)
96
{
97
  gdb_byte buf[4];
98
  unsigned long insn;
99
  int i;
100
 
101
  /* If we can't read the instruction at PC, return zero.  */
102
  if (target_read_memory (pc, buf, sizeof (buf)))
103
    return 0;
104
 
105
  insn = 0;
106
  for (i = 0; i < sizeof (buf); i++)
107
    insn = (insn << 8) | buf[i];
108
  return insn;
109
}
110
 
111
 
112
/* Return non-zero if the instruction corresponding to PC is an "unimp"
113
   instruction.  */
114
 
115
static int
116
sparc_is_unimp_insn (CORE_ADDR pc)
117
{
118
  const unsigned long insn = sparc_fetch_instruction (pc);
119
 
120
  return ((insn & 0xc1c00000) == 0);
121
}
122
 
123
/* OpenBSD/sparc includes StackGhost, which according to the author's
124
   website http://stackghost.cerias.purdue.edu "... transparently and
125
   automatically protects applications' stack frames; more
126
   specifically, it guards the return pointers.  The protection
127
   mechanisms require no application source or binary modification and
128
   imposes only a negligible performance penalty."
129
 
130
   The same website provides the following description of how
131
   StackGhost works:
132
 
133
   "StackGhost interfaces with the kernel trap handler that would
134
   normally write out registers to the stack and the handler that
135
   would read them back in.  By XORing a cookie into the
136
   return-address saved in the user stack when it is actually written
137
   to the stack, and then XOR it out when the return-address is pulled
138
   from the stack, StackGhost can cause attacker corrupted return
139
   pointers to behave in a manner the attacker cannot predict.
140
   StackGhost can also use several unused bits in the return pointer
141
   to detect a smashed return pointer and abort the process."
142
 
143
   For GDB this means that whenever we're reading %i7 from a stack
144
   frame's window save area, we'll have to XOR the cookie.
145
 
146
   More information on StackGuard can be found on in:
147
 
148
   Mike Frantzen and Mike Shuey. "StackGhost: Hardware Facilitated
149
   Stack Protection."  2001.  Published in USENIX Security Symposium
150
   '01.  */
151
 
152
/* Fetch StackGhost Per-Process XOR cookie.  */
153
 
154
ULONGEST
155
sparc_fetch_wcookie (struct gdbarch *gdbarch)
156
{
157
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
158
  struct target_ops *ops = &current_target;
159
  gdb_byte buf[8];
160
  int len;
161
 
162
  len = target_read (ops, TARGET_OBJECT_WCOOKIE, NULL, buf, 0, 8);
163
  if (len == -1)
164
    return 0;
165
 
166
  /* We should have either an 32-bit or an 64-bit cookie.  */
167
  gdb_assert (len == 4 || len == 8);
168
 
169
  return extract_unsigned_integer (buf, len, byte_order);
170
}
171
 
172
 
173
/* The functions on this page are intended to be used to classify
174
   function arguments.  */
175
 
176
/* Check whether TYPE is "Integral or Pointer".  */
177
 
178
static int
179
sparc_integral_or_pointer_p (const struct type *type)
180
{
181
  int len = TYPE_LENGTH (type);
182
 
183
  switch (TYPE_CODE (type))
184
    {
185
    case TYPE_CODE_INT:
186
    case TYPE_CODE_BOOL:
187
    case TYPE_CODE_CHAR:
188
    case TYPE_CODE_ENUM:
189
    case TYPE_CODE_RANGE:
190
      /* We have byte, half-word, word and extended-word/doubleword
191
         integral types.  The doubleword is an extension to the
192
         original 32-bit ABI by the SCD 2.4.x.  */
193
      return (len == 1 || len == 2 || len == 4 || len == 8);
194
    case TYPE_CODE_PTR:
195
    case TYPE_CODE_REF:
196
      /* Allow either 32-bit or 64-bit pointers.  */
197
      return (len == 4 || len == 8);
198
    default:
199
      break;
200
    }
201
 
202
  return 0;
203
}
204
 
205
/* Check whether TYPE is "Floating".  */
206
 
207
static int
208
sparc_floating_p (const struct type *type)
209
{
210
  switch (TYPE_CODE (type))
211
    {
212
    case TYPE_CODE_FLT:
213
      {
214
        int len = TYPE_LENGTH (type);
215
        return (len == 4 || len == 8 || len == 16);
216
      }
217
    default:
218
      break;
219
    }
220
 
221
  return 0;
222
}
223
 
224
/* Check whether TYPE is "Structure or Union".  */
225
 
226
static int
227
sparc_structure_or_union_p (const struct type *type)
228
{
229
  switch (TYPE_CODE (type))
230
    {
231
    case TYPE_CODE_STRUCT:
232
    case TYPE_CODE_UNION:
233
      return 1;
234
    default:
235
      break;
236
    }
237
 
238
  return 0;
239
}
240
 
241
/* Register information.  */
242
 
243
static const char *sparc32_register_names[] =
244
{
245
  "g0", "g1", "g2", "g3", "g4", "g5", "g6", "g7",
246
  "o0", "o1", "o2", "o3", "o4", "o5", "sp", "o7",
247
  "l0", "l1", "l2", "l3", "l4", "l5", "l6", "l7",
248
  "i0", "i1", "i2", "i3", "i4", "i5", "fp", "i7",
249
 
250
  "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",
251
  "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
252
  "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
253
  "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
254
 
255
  "y", "psr", "wim", "tbr", "pc", "npc", "fsr", "csr"
256
};
257
 
258
/* Total number of registers.  */
259
#define SPARC32_NUM_REGS ARRAY_SIZE (sparc32_register_names)
260
 
261
/* We provide the aliases %d0..%d30 for the floating registers as
262
   "psuedo" registers.  */
263
 
264
static const char *sparc32_pseudo_register_names[] =
265
{
266
  "d0", "d2", "d4", "d6", "d8", "d10", "d12", "d14",
267
  "d16", "d18", "d20", "d22", "d24", "d26", "d28", "d30"
268
};
269
 
270
/* Total number of pseudo registers.  */
271
#define SPARC32_NUM_PSEUDO_REGS ARRAY_SIZE (sparc32_pseudo_register_names)
272
 
273
/* Return the name of register REGNUM.  */
274
 
275
static const char *
276
sparc32_register_name (struct gdbarch *gdbarch, int regnum)
277
{
278
  if (regnum >= 0 && regnum < SPARC32_NUM_REGS)
279
    return sparc32_register_names[regnum];
280
 
281
  if (regnum < SPARC32_NUM_REGS + SPARC32_NUM_PSEUDO_REGS)
282
    return sparc32_pseudo_register_names[regnum - SPARC32_NUM_REGS];
283
 
284
  return NULL;
285
}
286
 
287
/* Construct types for ISA-specific registers.  */
288
 
289
static struct type *
290
sparc_psr_type (struct gdbarch *gdbarch)
291
{
292
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
293
 
294
  if (!tdep->sparc_psr_type)
295
    {
296
      struct type *type;
297
 
298
      type = arch_flags_type (gdbarch, "builtin_type_sparc_psr", 4);
299
      append_flags_type_flag (type, 5, "ET");
300
      append_flags_type_flag (type, 6, "PS");
301
      append_flags_type_flag (type, 7, "S");
302
      append_flags_type_flag (type, 12, "EF");
303
      append_flags_type_flag (type, 13, "EC");
304
 
305
      tdep->sparc_psr_type = type;
306
    }
307
 
308
  return tdep->sparc_psr_type;
309
}
310
 
311
static struct type *
312
sparc_fsr_type (struct gdbarch *gdbarch)
313
{
314
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
315
 
316
  if (!tdep->sparc_fsr_type)
317
    {
318
      struct type *type;
319
 
320
      type = arch_flags_type (gdbarch, "builtin_type_sparc_fsr", 4);
321
      append_flags_type_flag (type, 0, "NXA");
322
      append_flags_type_flag (type, 1, "DZA");
323
      append_flags_type_flag (type, 2, "UFA");
324
      append_flags_type_flag (type, 3, "OFA");
325
      append_flags_type_flag (type, 4, "NVA");
326
      append_flags_type_flag (type, 5, "NXC");
327
      append_flags_type_flag (type, 6, "DZC");
328
      append_flags_type_flag (type, 7, "UFC");
329
      append_flags_type_flag (type, 8, "OFC");
330
      append_flags_type_flag (type, 9, "NVC");
331
      append_flags_type_flag (type, 22, "NS");
332
      append_flags_type_flag (type, 23, "NXM");
333
      append_flags_type_flag (type, 24, "DZM");
334
      append_flags_type_flag (type, 25, "UFM");
335
      append_flags_type_flag (type, 26, "OFM");
336
      append_flags_type_flag (type, 27, "NVM");
337
 
338
      tdep->sparc_fsr_type = type;
339
    }
340
 
341
  return tdep->sparc_fsr_type;
342
}
343
 
344
/* Return the GDB type object for the "standard" data type of data in
345
   register REGNUM. */
346
 
347
static struct type *
348
sparc32_register_type (struct gdbarch *gdbarch, int regnum)
349
{
350
  if (regnum >= SPARC_F0_REGNUM && regnum <= SPARC_F31_REGNUM)
351
    return builtin_type (gdbarch)->builtin_float;
352
 
353
  if (regnum >= SPARC32_D0_REGNUM && regnum <= SPARC32_D30_REGNUM)
354
    return builtin_type (gdbarch)->builtin_double;
355
 
356
  if (regnum == SPARC_SP_REGNUM || regnum == SPARC_FP_REGNUM)
357
    return builtin_type (gdbarch)->builtin_data_ptr;
358
 
359
  if (regnum == SPARC32_PC_REGNUM || regnum == SPARC32_NPC_REGNUM)
360
    return builtin_type (gdbarch)->builtin_func_ptr;
361
 
362
  if (regnum == SPARC32_PSR_REGNUM)
363
    return sparc_psr_type (gdbarch);
364
 
365
  if (regnum == SPARC32_FSR_REGNUM)
366
    return sparc_fsr_type (gdbarch);
367
 
368
  return builtin_type (gdbarch)->builtin_int32;
369
}
370
 
371
static void
372
sparc32_pseudo_register_read (struct gdbarch *gdbarch,
373
                              struct regcache *regcache,
374
                              int regnum, gdb_byte *buf)
375
{
376
  gdb_assert (regnum >= SPARC32_D0_REGNUM && regnum <= SPARC32_D30_REGNUM);
377
 
378
  regnum = SPARC_F0_REGNUM + 2 * (regnum - SPARC32_D0_REGNUM);
379
  regcache_raw_read (regcache, regnum, buf);
380
  regcache_raw_read (regcache, regnum + 1, buf + 4);
381
}
382
 
383
static void
384
sparc32_pseudo_register_write (struct gdbarch *gdbarch,
385
                               struct regcache *regcache,
386
                               int regnum, const gdb_byte *buf)
387
{
388
  gdb_assert (regnum >= SPARC32_D0_REGNUM && regnum <= SPARC32_D30_REGNUM);
389
 
390
  regnum = SPARC_F0_REGNUM + 2 * (regnum - SPARC32_D0_REGNUM);
391
  regcache_raw_write (regcache, regnum, buf);
392
  regcache_raw_write (regcache, regnum + 1, buf + 4);
393
}
394
 
395
 
396
static CORE_ADDR
397
sparc32_push_dummy_code (struct gdbarch *gdbarch, CORE_ADDR sp,
398
                         CORE_ADDR funcaddr,
399
                         struct value **args, int nargs,
400
                         struct type *value_type,
401
                         CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
402
                         struct regcache *regcache)
403
{
404
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
405
 
406
  *bp_addr = sp - 4;
407
  *real_pc = funcaddr;
408
 
409
  if (using_struct_return (gdbarch, NULL, value_type))
410
    {
411
      gdb_byte buf[4];
412
 
413
      /* This is an UNIMP instruction.  */
414
      store_unsigned_integer (buf, 4, byte_order,
415
                              TYPE_LENGTH (value_type) & 0x1fff);
416
      write_memory (sp - 8, buf, 4);
417
      return sp - 8;
418
    }
419
 
420
  return sp - 4;
421
}
422
 
423
static CORE_ADDR
424
sparc32_store_arguments (struct regcache *regcache, int nargs,
425
                         struct value **args, CORE_ADDR sp,
426
                         int struct_return, CORE_ADDR struct_addr)
427
{
428
  struct gdbarch *gdbarch = get_regcache_arch (regcache);
429
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
430
  /* Number of words in the "parameter array".  */
431
  int num_elements = 0;
432
  int element = 0;
433
  int i;
434
 
435
  for (i = 0; i < nargs; i++)
436
    {
437
      struct type *type = value_type (args[i]);
438
      int len = TYPE_LENGTH (type);
439
 
440
      if (sparc_structure_or_union_p (type)
441
          || (sparc_floating_p (type) && len == 16))
442
        {
443
          /* Structure, Union and Quad-Precision Arguments.  */
444
          sp -= len;
445
 
446
          /* Use doubleword alignment for these values.  That's always
447
             correct, and wasting a few bytes shouldn't be a problem.  */
448
          sp &= ~0x7;
449
 
450
          write_memory (sp, value_contents (args[i]), len);
451
          args[i] = value_from_pointer (lookup_pointer_type (type), sp);
452
          num_elements++;
453
        }
454
      else if (sparc_floating_p (type))
455
        {
456
          /* Floating arguments.  */
457
          gdb_assert (len == 4 || len == 8);
458
          num_elements += (len / 4);
459
        }
460
      else
461
        {
462
          /* Integral and pointer arguments.  */
463
          gdb_assert (sparc_integral_or_pointer_p (type));
464
 
465
          if (len < 4)
466
            args[i] = value_cast (builtin_type (gdbarch)->builtin_int32,
467
                                  args[i]);
468
          num_elements += ((len + 3) / 4);
469
        }
470
    }
471
 
472
  /* Always allocate at least six words.  */
473
  sp -= max (6, num_elements) * 4;
474
 
475
  /* The psABI says that "Software convention requires space for the
476
     struct/union return value pointer, even if the word is unused."  */
477
  sp -= 4;
478
 
479
  /* The psABI says that "Although software convention and the
480
     operating system require every stack frame to be doubleword
481
     aligned."  */
482
  sp &= ~0x7;
483
 
484
  for (i = 0; i < nargs; i++)
485
    {
486
      const bfd_byte *valbuf = value_contents (args[i]);
487
      struct type *type = value_type (args[i]);
488
      int len = TYPE_LENGTH (type);
489
 
490
      gdb_assert (len == 4 || len == 8);
491
 
492
      if (element < 6)
493
        {
494
          int regnum = SPARC_O0_REGNUM + element;
495
 
496
          regcache_cooked_write (regcache, regnum, valbuf);
497
          if (len > 4 && element < 5)
498
            regcache_cooked_write (regcache, regnum + 1, valbuf + 4);
499
        }
500
 
501
      /* Always store the argument in memory.  */
502
      write_memory (sp + 4 + element * 4, valbuf, len);
503
      element += len / 4;
504
    }
505
 
506
  gdb_assert (element == num_elements);
507
 
508
  if (struct_return)
509
    {
510
      gdb_byte buf[4];
511
 
512
      store_unsigned_integer (buf, 4, byte_order, struct_addr);
513
      write_memory (sp, buf, 4);
514
    }
515
 
516
  return sp;
517
}
518
 
519
static CORE_ADDR
520
sparc32_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
521
                         struct regcache *regcache, CORE_ADDR bp_addr,
522
                         int nargs, struct value **args, CORE_ADDR sp,
523
                         int struct_return, CORE_ADDR struct_addr)
524
{
525
  CORE_ADDR call_pc = (struct_return ? (bp_addr - 12) : (bp_addr - 8));
526
 
527
  /* Set return address.  */
528
  regcache_cooked_write_unsigned (regcache, SPARC_O7_REGNUM, call_pc);
529
 
530
  /* Set up function arguments.  */
531
  sp = sparc32_store_arguments (regcache, nargs, args, sp,
532
                                struct_return, struct_addr);
533
 
534
  /* Allocate the 16-word window save area.  */
535
  sp -= 16 * 4;
536
 
537
  /* Stack should be doubleword aligned at this point.  */
538
  gdb_assert (sp % 8 == 0);
539
 
540
  /* Finally, update the stack pointer.  */
541
  regcache_cooked_write_unsigned (regcache, SPARC_SP_REGNUM, sp);
542
 
543
  return sp;
544
}
545
 
546
 
547
/* Use the program counter to determine the contents and size of a
548
   breakpoint instruction.  Return a pointer to a string of bytes that
549
   encode a breakpoint instruction, store the length of the string in
550
   *LEN and optionally adjust *PC to point to the correct memory
551
   location for inserting the breakpoint.  */
552
 
553
static const gdb_byte *
554
sparc_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pc, int *len)
555
{
556
  static const gdb_byte break_insn[] = { 0x91, 0xd0, 0x20, 0x01 };
557
 
558
  *len = sizeof (break_insn);
559
  return break_insn;
560
}
561
 
562
 
563
/* Allocate and initialize a frame cache.  */
564
 
565
static struct sparc_frame_cache *
566
sparc_alloc_frame_cache (void)
567
{
568
  struct sparc_frame_cache *cache;
569
  int i;
570
 
571
  cache = FRAME_OBSTACK_ZALLOC (struct sparc_frame_cache);
572
 
573
  /* Base address.  */
574
  cache->base = 0;
575
  cache->pc = 0;
576
 
577
  /* Frameless until proven otherwise.  */
578
  cache->frameless_p = 1;
579
 
580
  cache->struct_return_p = 0;
581
 
582
  return cache;
583
}
584
 
585
/* GCC generates several well-known sequences of instructions at the begining
586
   of each function prologue when compiling with -fstack-check.  If one of
587
   such sequences starts at START_PC, then return the address of the
588
   instruction immediately past this sequence.  Otherwise, return START_PC.  */
589
 
590
static CORE_ADDR
591
sparc_skip_stack_check (const CORE_ADDR start_pc)
592
{
593
  CORE_ADDR pc = start_pc;
594
  unsigned long insn;
595
  int offset_stack_checking_sequence = 0;
596
 
597
  /* With GCC, all stack checking sequences begin with the same two
598
     instructions.  */
599
 
600
  /* sethi <some immediate>,%g1 */
601
  insn = sparc_fetch_instruction (pc);
602
  pc = pc + 4;
603
  if (!(X_OP (insn) == 0 && X_OP2 (insn) == 0x4 && X_RD (insn) == 1))
604
    return start_pc;
605
 
606
  /* sub %sp, %g1, %g1 */
607
  insn = sparc_fetch_instruction (pc);
608
  pc = pc + 4;
609
  if (!(X_OP (insn) == 2 && X_OP3 (insn) == 0x4 && !X_I(insn)
610
        && X_RD (insn) == 1 && X_RS1 (insn) == 14 && X_RS2 (insn) == 1))
611
    return start_pc;
612
 
613
  insn = sparc_fetch_instruction (pc);
614
  pc = pc + 4;
615
 
616
  /* First possible sequence:
617
         [first two instructions above]
618
         clr [%g1 - some immediate]  */
619
 
620
  /* clr [%g1 - some immediate]  */
621
  if (X_OP (insn) == 3 && X_OP3(insn) == 0x4 && X_I(insn)
622
      && X_RS1 (insn) == 1 && X_RD (insn) == 0)
623
    {
624
      /* Valid stack-check sequence, return the new PC.  */
625
      return pc;
626
    }
627
 
628
  /* Second possible sequence: A small number of probes.
629
         [first two instructions above]
630
         clr [%g1]
631
         add   %g1, -<some immediate>, %g1
632
         clr [%g1]
633
         [repeat the two instructions above any (small) number of times]
634
         clr [%g1 - some immediate]  */
635
 
636
  /* clr [%g1] */
637
  else if (X_OP (insn) == 3 && X_OP3(insn) == 0x4 && !X_I(insn)
638
      && X_RS1 (insn) == 1 && X_RD (insn) == 0)
639
    {
640
      while (1)
641
        {
642
          /* add %g1, -<some immediate>, %g1 */
643
          insn = sparc_fetch_instruction (pc);
644
          pc = pc + 4;
645
          if (!(X_OP (insn) == 2  && X_OP3(insn) == 0 && X_I(insn)
646
                && X_RS1 (insn) == 1 && X_RD (insn) == 1))
647
            break;
648
 
649
          /* clr [%g1] */
650
          insn = sparc_fetch_instruction (pc);
651
          pc = pc + 4;
652
          if (!(X_OP (insn) == 3 && X_OP3(insn) == 0x4 && !X_I(insn)
653
                && X_RD (insn) == 0 && X_RS1 (insn) == 1))
654
            return start_pc;
655
        }
656
 
657
      /* clr [%g1 - some immediate] */
658
      if (!(X_OP (insn) == 3 && X_OP3(insn) == 0x4 && X_I(insn)
659
            && X_RS1 (insn) == 1 && X_RD (insn) == 0))
660
        return start_pc;
661
 
662
      /* We found a valid stack-check sequence, return the new PC.  */
663
      return pc;
664
    }
665
 
666
  /* Third sequence: A probing loop.
667
         [first two instructions above]
668
         sethi  <some immediate>, %g4
669
         sub  %g1, %g4, %g4
670
         cmp  %g1, %g4
671
         be  <disp>
672
         add  %g1, -<some immediate>, %g1
673
         ba  <disp>
674
         clr  [%g1]
675
         clr [%g4 - some immediate]  */
676
 
677
  /* sethi  <some immediate>, %g4 */
678
  else if (X_OP (insn) == 0 && X_OP2 (insn) == 0x4 && X_RD (insn) == 4)
679
    {
680
      /* sub  %g1, %g4, %g4 */
681
      insn = sparc_fetch_instruction (pc);
682
      pc = pc + 4;
683
      if (!(X_OP (insn) == 2 && X_OP3 (insn) == 0x4 && !X_I(insn)
684
            && X_RD (insn) == 4 && X_RS1 (insn) == 1 && X_RS2 (insn) == 4))
685
        return start_pc;
686
 
687
      /* cmp  %g1, %g4 */
688
      insn = sparc_fetch_instruction (pc);
689
      pc = pc + 4;
690
      if (!(X_OP (insn) == 2 && X_OP3 (insn) == 0x14 && !X_I(insn)
691
            && X_RD (insn) == 0 && X_RS1 (insn) == 1 && X_RS2 (insn) == 4))
692
        return start_pc;
693
 
694
      /* be  <disp> */
695
      insn = sparc_fetch_instruction (pc);
696
      pc = pc + 4;
697
      if (!(X_OP (insn) == 0 && X_COND (insn) == 0x1))
698
        return start_pc;
699
 
700
      /* add  %g1, -<some immediate>, %g1 */
701
      insn = sparc_fetch_instruction (pc);
702
      pc = pc + 4;
703
      if (!(X_OP (insn) == 2  && X_OP3(insn) == 0 && X_I(insn)
704
            && X_RS1 (insn) == 1 && X_RD (insn) == 1))
705
        return start_pc;
706
 
707
      /* ba  <disp> */
708
      insn = sparc_fetch_instruction (pc);
709
      pc = pc + 4;
710
      if (!(X_OP (insn) == 0 && X_COND (insn) == 0x8))
711
        return start_pc;
712
 
713
      /* clr  [%g1] */
714
      insn = sparc_fetch_instruction (pc);
715
      pc = pc + 4;
716
      if (!(X_OP (insn) == 3 && X_OP3(insn) == 0x4 && !X_I(insn)
717
            && X_RD (insn) == 0 && X_RS1 (insn) == 1))
718
        return start_pc;
719
 
720
      /* clr [%g4 - some immediate]  */
721
      insn = sparc_fetch_instruction (pc);
722
      pc = pc + 4;
723
      if (!(X_OP (insn) == 3 && X_OP3(insn) == 0x4 && X_I(insn)
724
            && X_RS1 (insn) == 4 && X_RD (insn) == 0))
725
        return start_pc;
726
 
727
      /* We found a valid stack-check sequence, return the new PC.  */
728
      return pc;
729
    }
730
 
731
  /* No stack check code in our prologue, return the start_pc.  */
732
  return start_pc;
733
}
734
 
735
CORE_ADDR
736
sparc_analyze_prologue (struct gdbarch *gdbarch, CORE_ADDR pc,
737
                        CORE_ADDR current_pc, struct sparc_frame_cache *cache)
738
{
739
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
740
  unsigned long insn;
741
  int offset = 0;
742
  int dest = -1;
743
 
744
  pc = sparc_skip_stack_check (pc);
745
 
746
  if (current_pc <= pc)
747
    return current_pc;
748
 
749
  /* We have to handle to "Procedure Linkage Table" (PLT) special.  On
750
     SPARC the linker usually defines a symbol (typically
751
     _PROCEDURE_LINKAGE_TABLE_) at the start of the .plt section.
752
     This symbol makes us end up here with PC pointing at the start of
753
     the PLT and CURRENT_PC probably pointing at a PLT entry.  If we
754
     would do our normal prologue analysis, we would probably conclude
755
     that we've got a frame when in reality we don't, since the
756
     dynamic linker patches up the first PLT with some code that
757
     starts with a SAVE instruction.  Patch up PC such that it points
758
     at the start of our PLT entry.  */
759
  if (tdep->plt_entry_size > 0 && in_plt_section (current_pc, NULL))
760
    pc = current_pc - ((current_pc - pc) % tdep->plt_entry_size);
761
 
762
  insn = sparc_fetch_instruction (pc);
763
 
764
  /* Recognize a SETHI insn and record its destination.  */
765
  if (X_OP (insn) == 0 && X_OP2 (insn) == 0x04)
766
    {
767
      dest = X_RD (insn);
768
      offset += 4;
769
 
770
      insn = sparc_fetch_instruction (pc + 4);
771
    }
772
 
773
  /* Allow for an arithmetic operation on DEST or %g1.  */
774
  if (X_OP (insn) == 2 && X_I (insn)
775
      && (X_RD (insn) == 1 || X_RD (insn) == dest))
776
    {
777
      offset += 4;
778
 
779
      insn = sparc_fetch_instruction (pc + 8);
780
    }
781
 
782
  /* Check for the SAVE instruction that sets up the frame.  */
783
  if (X_OP (insn) == 2 && X_OP3 (insn) == 0x3c)
784
    {
785
      cache->frameless_p = 0;
786
      return pc + offset + 4;
787
    }
788
 
789
  return pc;
790
}
791
 
792
static CORE_ADDR
793
sparc_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
794
{
795
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
796
  return frame_unwind_register_unsigned (this_frame, tdep->pc_regnum);
797
}
798
 
799
/* Return PC of first real instruction of the function starting at
800
   START_PC.  */
801
 
802
static CORE_ADDR
803
sparc32_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR start_pc)
804
{
805
  struct symtab_and_line sal;
806
  CORE_ADDR func_start, func_end;
807
  struct sparc_frame_cache cache;
808
 
809
  /* This is the preferred method, find the end of the prologue by
810
     using the debugging information.  */
811
  if (find_pc_partial_function (start_pc, NULL, &func_start, &func_end))
812
    {
813
      sal = find_pc_line (func_start, 0);
814
 
815
      if (sal.end < func_end
816
          && start_pc <= sal.end)
817
        return sal.end;
818
    }
819
 
820
  start_pc = sparc_analyze_prologue (gdbarch, start_pc, 0xffffffffUL, &cache);
821
 
822
  /* The psABI says that "Although the first 6 words of arguments
823
     reside in registers, the standard stack frame reserves space for
824
     them.".  It also suggests that a function may use that space to
825
     "write incoming arguments 0 to 5" into that space, and that's
826
     indeed what GCC seems to be doing.  In that case GCC will
827
     generate debug information that points to the stack slots instead
828
     of the registers, so we should consider the instructions that
829
     write out these incoming arguments onto the stack.  Of course we
830
     only need to do this if we have a stack frame.  */
831
 
832
  while (!cache.frameless_p)
833
    {
834
      unsigned long insn = sparc_fetch_instruction (start_pc);
835
 
836
      /* Recognize instructions that store incoming arguments in
837
         %i0...%i5 into the corresponding stack slot.  */
838
      if (X_OP (insn) == 3 && (X_OP3 (insn) & 0x3c) == 0x04 && X_I (insn)
839
          && (X_RD (insn) >= 24 && X_RD (insn) <= 29) && X_RS1 (insn) == 30
840
          && X_SIMM13 (insn) == 68 + (X_RD (insn) - 24) * 4)
841
        {
842
          start_pc += 4;
843
          continue;
844
        }
845
 
846
      break;
847
    }
848
 
849
  return start_pc;
850
}
851
 
852
/* Normal frames.  */
853
 
854
struct sparc_frame_cache *
855
sparc_frame_cache (struct frame_info *this_frame, void **this_cache)
856
{
857
  struct sparc_frame_cache *cache;
858
 
859
  if (*this_cache)
860
    return *this_cache;
861
 
862
  cache = sparc_alloc_frame_cache ();
863
  *this_cache = cache;
864
 
865
  cache->pc = get_frame_func (this_frame);
866
  if (cache->pc != 0)
867
    sparc_analyze_prologue (get_frame_arch (this_frame), cache->pc,
868
                            get_frame_pc (this_frame), cache);
869
 
870
  if (cache->frameless_p)
871
    {
872
      /* This function is frameless, so %fp (%i6) holds the frame
873
         pointer for our calling frame.  Use %sp (%o6) as this frame's
874
         base address.  */
875
      cache->base =
876
        get_frame_register_unsigned (this_frame, SPARC_SP_REGNUM);
877
    }
878
  else
879
    {
880
      /* For normal frames, %fp (%i6) holds the frame pointer, the
881
         base address for the current stack frame.  */
882
      cache->base =
883
        get_frame_register_unsigned (this_frame, SPARC_FP_REGNUM);
884
    }
885
 
886
  if (cache->base & 1)
887
    cache->base += BIAS;
888
 
889
  return cache;
890
}
891
 
892
static int
893
sparc32_struct_return_from_sym (struct symbol *sym)
894
{
895
  struct type *type = check_typedef (SYMBOL_TYPE (sym));
896
  enum type_code code = TYPE_CODE (type);
897
 
898
  if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
899
    {
900
      type = check_typedef (TYPE_TARGET_TYPE (type));
901
      if (sparc_structure_or_union_p (type)
902
          || (sparc_floating_p (type) && TYPE_LENGTH (type) == 16))
903
        return 1;
904
    }
905
 
906
  return 0;
907
}
908
 
909
struct sparc_frame_cache *
910
sparc32_frame_cache (struct frame_info *this_frame, void **this_cache)
911
{
912
  struct sparc_frame_cache *cache;
913
  struct symbol *sym;
914
 
915
  if (*this_cache)
916
    return *this_cache;
917
 
918
  cache = sparc_frame_cache (this_frame, this_cache);
919
 
920
  sym = find_pc_function (cache->pc);
921
  if (sym)
922
    {
923
      cache->struct_return_p = sparc32_struct_return_from_sym (sym);
924
    }
925
  else
926
    {
927
      /* There is no debugging information for this function to
928
         help us determine whether this function returns a struct
929
         or not.  So we rely on another heuristic which is to check
930
         the instruction at the return address and see if this is
931
         an "unimp" instruction.  If it is, then it is a struct-return
932
         function.  */
933
      CORE_ADDR pc;
934
      int regnum = cache->frameless_p ? SPARC_O7_REGNUM : SPARC_I7_REGNUM;
935
 
936
      pc = get_frame_register_unsigned (this_frame, regnum) + 8;
937
      if (sparc_is_unimp_insn (pc))
938
        cache->struct_return_p = 1;
939
    }
940
 
941
  return cache;
942
}
943
 
944
static void
945
sparc32_frame_this_id (struct frame_info *this_frame, void **this_cache,
946
                       struct frame_id *this_id)
947
{
948
  struct sparc_frame_cache *cache =
949
    sparc32_frame_cache (this_frame, this_cache);
950
 
951
  /* This marks the outermost frame.  */
952
  if (cache->base == 0)
953
    return;
954
 
955
  (*this_id) = frame_id_build (cache->base, cache->pc);
956
}
957
 
958
static struct value *
959
sparc32_frame_prev_register (struct frame_info *this_frame,
960
                             void **this_cache, int regnum)
961
{
962
  struct gdbarch *gdbarch = get_frame_arch (this_frame);
963
  struct sparc_frame_cache *cache =
964
    sparc32_frame_cache (this_frame, this_cache);
965
 
966
  if (regnum == SPARC32_PC_REGNUM || regnum == SPARC32_NPC_REGNUM)
967
    {
968
      CORE_ADDR pc = (regnum == SPARC32_NPC_REGNUM) ? 4 : 0;
969
 
970
      /* If this functions has a Structure, Union or Quad-Precision
971
         return value, we have to skip the UNIMP instruction that encodes
972
         the size of the structure.  */
973
      if (cache->struct_return_p)
974
        pc += 4;
975
 
976
      regnum = cache->frameless_p ? SPARC_O7_REGNUM : SPARC_I7_REGNUM;
977
      pc += get_frame_register_unsigned (this_frame, regnum) + 8;
978
      return frame_unwind_got_constant (this_frame, regnum, pc);
979
    }
980
 
981
  /* Handle StackGhost.  */
982
  {
983
    ULONGEST wcookie = sparc_fetch_wcookie (gdbarch);
984
 
985
    if (wcookie != 0 && !cache->frameless_p && regnum == SPARC_I7_REGNUM)
986
      {
987
        CORE_ADDR addr = cache->base + (regnum - SPARC_L0_REGNUM) * 4;
988
        ULONGEST i7;
989
 
990
        /* Read the value in from memory.  */
991
        i7 = get_frame_memory_unsigned (this_frame, addr, 4);
992
        return frame_unwind_got_constant (this_frame, regnum, i7 ^ wcookie);
993
      }
994
  }
995
 
996
  /* The previous frame's `local' and `in' registers have been saved
997
     in the register save area.  */
998
  if (!cache->frameless_p
999
      && regnum >= SPARC_L0_REGNUM && regnum <= SPARC_I7_REGNUM)
1000
    {
1001
      CORE_ADDR addr = cache->base + (regnum - SPARC_L0_REGNUM) * 4;
1002
 
1003
      return frame_unwind_got_memory (this_frame, regnum, addr);
1004
    }
1005
 
1006
  /* The previous frame's `out' registers are accessible as the
1007
     current frame's `in' registers.  */
1008
  if (!cache->frameless_p
1009
      && regnum >= SPARC_O0_REGNUM && regnum <= SPARC_O7_REGNUM)
1010
    regnum += (SPARC_I0_REGNUM - SPARC_O0_REGNUM);
1011
 
1012
  return frame_unwind_got_register (this_frame, regnum, regnum);
1013
}
1014
 
1015
static const struct frame_unwind sparc32_frame_unwind =
1016
{
1017
  NORMAL_FRAME,
1018
  sparc32_frame_this_id,
1019
  sparc32_frame_prev_register,
1020
  NULL,
1021
  default_frame_sniffer
1022
};
1023
 
1024
 
1025
static CORE_ADDR
1026
sparc32_frame_base_address (struct frame_info *this_frame, void **this_cache)
1027
{
1028
  struct sparc_frame_cache *cache =
1029
    sparc32_frame_cache (this_frame, this_cache);
1030
 
1031
  return cache->base;
1032
}
1033
 
1034
static const struct frame_base sparc32_frame_base =
1035
{
1036
  &sparc32_frame_unwind,
1037
  sparc32_frame_base_address,
1038
  sparc32_frame_base_address,
1039
  sparc32_frame_base_address
1040
};
1041
 
1042
static struct frame_id
1043
sparc_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
1044
{
1045
  CORE_ADDR sp;
1046
 
1047
  sp = get_frame_register_unsigned (this_frame, SPARC_SP_REGNUM);
1048
  if (sp & 1)
1049
    sp += BIAS;
1050
  return frame_id_build (sp, get_frame_pc (this_frame));
1051
}
1052
 
1053
 
1054
/* Extract a function return value of TYPE from REGCACHE, and copy
1055
   that into VALBUF.  */
1056
 
1057
static void
1058
sparc32_extract_return_value (struct type *type, struct regcache *regcache,
1059
                              gdb_byte *valbuf)
1060
{
1061
  int len = TYPE_LENGTH (type);
1062
  gdb_byte buf[8];
1063
 
1064
  gdb_assert (!sparc_structure_or_union_p (type));
1065
  gdb_assert (!(sparc_floating_p (type) && len == 16));
1066
 
1067
  if (sparc_floating_p (type))
1068
    {
1069
      /* Floating return values.  */
1070
      regcache_cooked_read (regcache, SPARC_F0_REGNUM, buf);
1071
      if (len > 4)
1072
        regcache_cooked_read (regcache, SPARC_F1_REGNUM, buf + 4);
1073
      memcpy (valbuf, buf, len);
1074
    }
1075
  else
1076
    {
1077
      /* Integral and pointer return values.  */
1078
      gdb_assert (sparc_integral_or_pointer_p (type));
1079
 
1080
      regcache_cooked_read (regcache, SPARC_O0_REGNUM, buf);
1081
      if (len > 4)
1082
        {
1083
          regcache_cooked_read (regcache, SPARC_O1_REGNUM, buf + 4);
1084
          gdb_assert (len == 8);
1085
          memcpy (valbuf, buf, 8);
1086
        }
1087
      else
1088
        {
1089
          /* Just stripping off any unused bytes should preserve the
1090
             signed-ness just fine.  */
1091
          memcpy (valbuf, buf + 4 - len, len);
1092
        }
1093
    }
1094
}
1095
 
1096
/* Store the function return value of type TYPE from VALBUF into
1097
   REGCACHE.  */
1098
 
1099
static void
1100
sparc32_store_return_value (struct type *type, struct regcache *regcache,
1101
                            const gdb_byte *valbuf)
1102
{
1103
  int len = TYPE_LENGTH (type);
1104
  gdb_byte buf[8];
1105
 
1106
  gdb_assert (!sparc_structure_or_union_p (type));
1107
  gdb_assert (!(sparc_floating_p (type) && len == 16));
1108
 
1109
  if (sparc_floating_p (type))
1110
    {
1111
      /* Floating return values.  */
1112
      memcpy (buf, valbuf, len);
1113
      regcache_cooked_write (regcache, SPARC_F0_REGNUM, buf);
1114
      if (len > 4)
1115
        regcache_cooked_write (regcache, SPARC_F1_REGNUM, buf + 4);
1116
    }
1117
  else
1118
    {
1119
      /* Integral and pointer return values.  */
1120
      gdb_assert (sparc_integral_or_pointer_p (type));
1121
 
1122
      if (len > 4)
1123
        {
1124
          gdb_assert (len == 8);
1125
          memcpy (buf, valbuf, 8);
1126
          regcache_cooked_write (regcache, SPARC_O1_REGNUM, buf + 4);
1127
        }
1128
      else
1129
        {
1130
          /* ??? Do we need to do any sign-extension here?  */
1131
          memcpy (buf + 4 - len, valbuf, len);
1132
        }
1133
      regcache_cooked_write (regcache, SPARC_O0_REGNUM, buf);
1134
    }
1135
}
1136
 
1137
static enum return_value_convention
1138
sparc32_return_value (struct gdbarch *gdbarch, struct type *func_type,
1139
                      struct type *type, struct regcache *regcache,
1140
                      gdb_byte *readbuf, const gdb_byte *writebuf)
1141
{
1142
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
1143
 
1144
  /* The psABI says that "...every stack frame reserves the word at
1145
     %fp+64.  If a function returns a structure, union, or
1146
     quad-precision value, this word should hold the address of the
1147
     object into which the return value should be copied."  This
1148
     guarantees that we can always find the return value, not just
1149
     before the function returns.  */
1150
 
1151
  if (sparc_structure_or_union_p (type)
1152
      || (sparc_floating_p (type) && TYPE_LENGTH (type) == 16))
1153
    {
1154
      if (readbuf)
1155
        {
1156
          ULONGEST sp;
1157
          CORE_ADDR addr;
1158
 
1159
          regcache_cooked_read_unsigned (regcache, SPARC_SP_REGNUM, &sp);
1160
          addr = read_memory_unsigned_integer (sp + 64, 4, byte_order);
1161
          read_memory (addr, readbuf, TYPE_LENGTH (type));
1162
        }
1163
 
1164
      return RETURN_VALUE_ABI_PRESERVES_ADDRESS;
1165
    }
1166
 
1167
  if (readbuf)
1168
    sparc32_extract_return_value (type, regcache, readbuf);
1169
  if (writebuf)
1170
    sparc32_store_return_value (type, regcache, writebuf);
1171
 
1172
  return RETURN_VALUE_REGISTER_CONVENTION;
1173
}
1174
 
1175
static int
1176
sparc32_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
1177
{
1178
  return (sparc_structure_or_union_p (type)
1179
          || (sparc_floating_p (type) && TYPE_LENGTH (type) == 16));
1180
}
1181
 
1182
static int
1183
sparc32_dwarf2_struct_return_p (struct frame_info *this_frame)
1184
{
1185
  CORE_ADDR pc = get_frame_address_in_block (this_frame);
1186
  struct symbol *sym = find_pc_function (pc);
1187
 
1188
  if (sym)
1189
    return sparc32_struct_return_from_sym (sym);
1190
  return 0;
1191
}
1192
 
1193
static void
1194
sparc32_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
1195
                               struct dwarf2_frame_state_reg *reg,
1196
                               struct frame_info *this_frame)
1197
{
1198
  int off;
1199
 
1200
  switch (regnum)
1201
    {
1202
    case SPARC_G0_REGNUM:
1203
      /* Since %g0 is always zero, there is no point in saving it, and
1204
         people will be inclined omit it from the CFI.  Make sure we
1205
         don't warn about that.  */
1206
      reg->how = DWARF2_FRAME_REG_SAME_VALUE;
1207
      break;
1208
    case SPARC_SP_REGNUM:
1209
      reg->how = DWARF2_FRAME_REG_CFA;
1210
      break;
1211
    case SPARC32_PC_REGNUM:
1212
    case SPARC32_NPC_REGNUM:
1213
      reg->how = DWARF2_FRAME_REG_RA_OFFSET;
1214
      off = 8;
1215
      if (sparc32_dwarf2_struct_return_p (this_frame))
1216
        off += 4;
1217
      if (regnum == SPARC32_NPC_REGNUM)
1218
        off += 4;
1219
      reg->loc.offset = off;
1220
      break;
1221
    }
1222
}
1223
 
1224
 
1225
/* The SPARC Architecture doesn't have hardware single-step support,
1226
   and most operating systems don't implement it either, so we provide
1227
   software single-step mechanism.  */
1228
 
1229
static CORE_ADDR
1230
sparc_analyze_control_transfer (struct frame_info *frame,
1231
                                CORE_ADDR pc, CORE_ADDR *npc)
1232
{
1233
  unsigned long insn = sparc_fetch_instruction (pc);
1234
  int conditional_p = X_COND (insn) & 0x7;
1235
  int branch_p = 0;
1236
  long offset = 0;                       /* Must be signed for sign-extend.  */
1237
 
1238
  if (X_OP (insn) == 0 && X_OP2 (insn) == 3 && (insn & 0x1000000) == 0)
1239
    {
1240
      /* Branch on Integer Register with Prediction (BPr).  */
1241
      branch_p = 1;
1242
      conditional_p = 1;
1243
    }
1244
  else if (X_OP (insn) == 0 && X_OP2 (insn) == 6)
1245
    {
1246
      /* Branch on Floating-Point Condition Codes (FBfcc).  */
1247
      branch_p = 1;
1248
      offset = 4 * X_DISP22 (insn);
1249
    }
1250
  else if (X_OP (insn) == 0 && X_OP2 (insn) == 5)
1251
    {
1252
      /* Branch on Floating-Point Condition Codes with Prediction
1253
         (FBPfcc).  */
1254
      branch_p = 1;
1255
      offset = 4 * X_DISP19 (insn);
1256
    }
1257
  else if (X_OP (insn) == 0 && X_OP2 (insn) == 2)
1258
    {
1259
      /* Branch on Integer Condition Codes (Bicc).  */
1260
      branch_p = 1;
1261
      offset = 4 * X_DISP22 (insn);
1262
    }
1263
  else if (X_OP (insn) == 0 && X_OP2 (insn) == 1)
1264
    {
1265
      /* Branch on Integer Condition Codes with Prediction (BPcc).  */
1266
      branch_p = 1;
1267
      offset = 4 * X_DISP19 (insn);
1268
    }
1269
  else if (X_OP (insn) == 2 && X_OP3 (insn) == 0x3a)
1270
    {
1271
      /* Trap instruction (TRAP).  */
1272
      return gdbarch_tdep (get_frame_arch (frame))->step_trap (frame, insn);
1273
    }
1274
 
1275
  /* FIXME: Handle DONE and RETRY instructions.  */
1276
 
1277
  if (branch_p)
1278
    {
1279
      if (conditional_p)
1280
        {
1281
          /* For conditional branches, return nPC + 4 iff the annul
1282
             bit is 1.  */
1283
          return (X_A (insn) ? *npc + 4 : 0);
1284
        }
1285
      else
1286
        {
1287
          /* For unconditional branches, return the target if its
1288
             specified condition is "always" and return nPC + 4 if the
1289
             condition is "never".  If the annul bit is 1, set *NPC to
1290
             zero.  */
1291
          if (X_COND (insn) == 0x0)
1292
            pc = *npc, offset = 4;
1293
          if (X_A (insn))
1294
            *npc = 0;
1295
 
1296
          gdb_assert (offset != 0);
1297
          return pc + offset;
1298
        }
1299
    }
1300
 
1301
  return 0;
1302
}
1303
 
1304
static CORE_ADDR
1305
sparc_step_trap (struct frame_info *frame, unsigned long insn)
1306
{
1307
  return 0;
1308
}
1309
 
1310
int
1311
sparc_software_single_step (struct frame_info *frame)
1312
{
1313
  struct gdbarch *arch = get_frame_arch (frame);
1314
  struct gdbarch_tdep *tdep = gdbarch_tdep (arch);
1315
  struct address_space *aspace = get_frame_address_space (frame);
1316
  CORE_ADDR npc, nnpc;
1317
 
1318
  CORE_ADDR pc, orig_npc;
1319
 
1320
  pc = get_frame_register_unsigned (frame, tdep->pc_regnum);
1321
  orig_npc = npc = get_frame_register_unsigned (frame, tdep->npc_regnum);
1322
 
1323
  /* Analyze the instruction at PC.  */
1324
  nnpc = sparc_analyze_control_transfer (frame, pc, &npc);
1325
  if (npc != 0)
1326
    insert_single_step_breakpoint (arch, aspace, npc);
1327
 
1328
  if (nnpc != 0)
1329
    insert_single_step_breakpoint (arch, aspace, nnpc);
1330
 
1331
  /* Assert that we have set at least one breakpoint, and that
1332
     they're not set at the same spot - unless we're going
1333
     from here straight to NULL, i.e. a call or jump to 0.  */
1334
  gdb_assert (npc != 0 || nnpc != 0 || orig_npc == 0);
1335
  gdb_assert (nnpc != npc || orig_npc == 0);
1336
 
1337
  return 1;
1338
}
1339
 
1340
static void
1341
sparc_write_pc (struct regcache *regcache, CORE_ADDR pc)
1342
{
1343
  struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
1344
 
1345
  regcache_cooked_write_unsigned (regcache, tdep->pc_regnum, pc);
1346
  regcache_cooked_write_unsigned (regcache, tdep->npc_regnum, pc + 4);
1347
}
1348
 
1349
 
1350
/* Return the appropriate register set for the core section identified
1351
   by SECT_NAME and SECT_SIZE.  */
1352
 
1353
static const struct regset *
1354
sparc_regset_from_core_section (struct gdbarch *gdbarch,
1355
                                const char *sect_name, size_t sect_size)
1356
{
1357
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
1358
 
1359
  if (strcmp (sect_name, ".reg") == 0 && sect_size >= tdep->sizeof_gregset)
1360
    return tdep->gregset;
1361
 
1362
  if (strcmp (sect_name, ".reg2") == 0 && sect_size >= tdep->sizeof_fpregset)
1363
    return tdep->fpregset;
1364
 
1365
  return NULL;
1366
}
1367
 
1368
 
1369
static struct gdbarch *
1370
sparc32_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
1371
{
1372
  struct gdbarch_tdep *tdep;
1373
  struct gdbarch *gdbarch;
1374
 
1375
  /* If there is already a candidate, use it.  */
1376
  arches = gdbarch_list_lookup_by_info (arches, &info);
1377
  if (arches != NULL)
1378
    return arches->gdbarch;
1379
 
1380
  /* Allocate space for the new architecture.  */
1381
  tdep = XZALLOC (struct gdbarch_tdep);
1382
  gdbarch = gdbarch_alloc (&info, tdep);
1383
 
1384
  tdep->pc_regnum = SPARC32_PC_REGNUM;
1385
  tdep->npc_regnum = SPARC32_NPC_REGNUM;
1386
  tdep->step_trap = sparc_step_trap;
1387
 
1388
  set_gdbarch_long_double_bit (gdbarch, 128);
1389
  set_gdbarch_long_double_format (gdbarch, floatformats_sparc_quad);
1390
 
1391
  set_gdbarch_num_regs (gdbarch, SPARC32_NUM_REGS);
1392
  set_gdbarch_register_name (gdbarch, sparc32_register_name);
1393
  set_gdbarch_register_type (gdbarch, sparc32_register_type);
1394
  set_gdbarch_num_pseudo_regs (gdbarch, SPARC32_NUM_PSEUDO_REGS);
1395
  set_gdbarch_pseudo_register_read (gdbarch, sparc32_pseudo_register_read);
1396
  set_gdbarch_pseudo_register_write (gdbarch, sparc32_pseudo_register_write);
1397
 
1398
  /* Register numbers of various important registers.  */
1399
  set_gdbarch_sp_regnum (gdbarch, SPARC_SP_REGNUM); /* %sp */
1400
  set_gdbarch_pc_regnum (gdbarch, SPARC32_PC_REGNUM); /* %pc */
1401
  set_gdbarch_fp0_regnum (gdbarch, SPARC_F0_REGNUM); /* %f0 */
1402
 
1403
  /* Call dummy code.  */
1404
  set_gdbarch_call_dummy_location (gdbarch, ON_STACK);
1405
  set_gdbarch_push_dummy_code (gdbarch, sparc32_push_dummy_code);
1406
  set_gdbarch_push_dummy_call (gdbarch, sparc32_push_dummy_call);
1407
 
1408
  set_gdbarch_return_value (gdbarch, sparc32_return_value);
1409
  set_gdbarch_stabs_argument_has_addr
1410
    (gdbarch, sparc32_stabs_argument_has_addr);
1411
 
1412
  set_gdbarch_skip_prologue (gdbarch, sparc32_skip_prologue);
1413
 
1414
  /* Stack grows downward.  */
1415
  set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
1416
 
1417
  set_gdbarch_breakpoint_from_pc (gdbarch, sparc_breakpoint_from_pc);
1418
 
1419
  set_gdbarch_frame_args_skip (gdbarch, 8);
1420
 
1421
  set_gdbarch_print_insn (gdbarch, print_insn_sparc);
1422
 
1423
  set_gdbarch_software_single_step (gdbarch, sparc_software_single_step);
1424
  set_gdbarch_write_pc (gdbarch, sparc_write_pc);
1425
 
1426
  set_gdbarch_dummy_id (gdbarch, sparc_dummy_id);
1427
 
1428
  set_gdbarch_unwind_pc (gdbarch, sparc_unwind_pc);
1429
 
1430
  frame_base_set_default (gdbarch, &sparc32_frame_base);
1431
 
1432
  /* Hook in the DWARF CFI frame unwinder.  */
1433
  dwarf2_frame_set_init_reg (gdbarch, sparc32_dwarf2_frame_init_reg);
1434
  /* FIXME: kettenis/20050423: Don't enable the unwinder until the
1435
     StackGhost issues have been resolved.  */
1436
 
1437
  /* Hook in ABI-specific overrides, if they have been registered.  */
1438
  gdbarch_init_osabi (info, gdbarch);
1439
 
1440
  frame_unwind_append_unwinder (gdbarch, &sparc32_frame_unwind);
1441
 
1442
  /* If we have register sets, enable the generic core file support.  */
1443
  if (tdep->gregset)
1444
    set_gdbarch_regset_from_core_section (gdbarch,
1445
                                          sparc_regset_from_core_section);
1446
 
1447
  return gdbarch;
1448
}
1449
 
1450
/* Helper functions for dealing with register windows.  */
1451
 
1452
void
1453
sparc_supply_rwindow (struct regcache *regcache, CORE_ADDR sp, int regnum)
1454
{
1455
  struct gdbarch *gdbarch = get_regcache_arch (regcache);
1456
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
1457
  int offset = 0;
1458
  gdb_byte buf[8];
1459
  int i;
1460
 
1461
  if (sp & 1)
1462
    {
1463
      /* Registers are 64-bit.  */
1464
      sp += BIAS;
1465
 
1466
      for (i = SPARC_L0_REGNUM; i <= SPARC_I7_REGNUM; i++)
1467
        {
1468
          if (regnum == i || regnum == -1)
1469
            {
1470
              target_read_memory (sp + ((i - SPARC_L0_REGNUM) * 8), buf, 8);
1471
 
1472
              /* Handle StackGhost.  */
1473
              if (i == SPARC_I7_REGNUM)
1474
                {
1475
                  ULONGEST wcookie = sparc_fetch_wcookie (gdbarch);
1476
                  ULONGEST i7;
1477
 
1478
                  i7 = extract_unsigned_integer (buf + offset, 8, byte_order);
1479
                  store_unsigned_integer (buf + offset, 8, byte_order,
1480
                                          i7 ^ wcookie);
1481
                }
1482
 
1483
              regcache_raw_supply (regcache, i, buf);
1484
            }
1485
        }
1486
    }
1487
  else
1488
    {
1489
      /* Registers are 32-bit.  Toss any sign-extension of the stack
1490
         pointer.  */
1491
      sp &= 0xffffffffUL;
1492
 
1493
      /* Clear out the top half of the temporary buffer, and put the
1494
         register value in the bottom half if we're in 64-bit mode.  */
1495
      if (gdbarch_ptr_bit (get_regcache_arch (regcache)) == 64)
1496
        {
1497
          memset (buf, 0, 4);
1498
          offset = 4;
1499
        }
1500
 
1501
      for (i = SPARC_L0_REGNUM; i <= SPARC_I7_REGNUM; i++)
1502
        {
1503
          if (regnum == i || regnum == -1)
1504
            {
1505
              target_read_memory (sp + ((i - SPARC_L0_REGNUM) * 4),
1506
                                  buf + offset, 4);
1507
 
1508
              /* Handle StackGhost.  */
1509
              if (i == SPARC_I7_REGNUM)
1510
                {
1511
                  ULONGEST wcookie = sparc_fetch_wcookie (gdbarch);
1512
                  ULONGEST i7;
1513
 
1514
                  i7 = extract_unsigned_integer (buf + offset, 4, byte_order);
1515
                  store_unsigned_integer (buf + offset, 4, byte_order,
1516
                                          i7 ^ wcookie);
1517
                }
1518
 
1519
              regcache_raw_supply (regcache, i, buf);
1520
            }
1521
        }
1522
    }
1523
}
1524
 
1525
void
1526
sparc_collect_rwindow (const struct regcache *regcache,
1527
                       CORE_ADDR sp, int regnum)
1528
{
1529
  struct gdbarch *gdbarch = get_regcache_arch (regcache);
1530
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
1531
  int offset = 0;
1532
  gdb_byte buf[8];
1533
  int i;
1534
 
1535
  if (sp & 1)
1536
    {
1537
      /* Registers are 64-bit.  */
1538
      sp += BIAS;
1539
 
1540
      for (i = SPARC_L0_REGNUM; i <= SPARC_I7_REGNUM; i++)
1541
        {
1542
          if (regnum == -1 || regnum == SPARC_SP_REGNUM || regnum == i)
1543
            {
1544
              regcache_raw_collect (regcache, i, buf);
1545
 
1546
              /* Handle StackGhost.  */
1547
              if (i == SPARC_I7_REGNUM)
1548
                {
1549
                  ULONGEST wcookie = sparc_fetch_wcookie (gdbarch);
1550
                  ULONGEST i7;
1551
 
1552
                  i7 = extract_unsigned_integer (buf + offset, 8, byte_order);
1553
                  store_unsigned_integer (buf, 8, byte_order, i7 ^ wcookie);
1554
                }
1555
 
1556
              target_write_memory (sp + ((i - SPARC_L0_REGNUM) * 8), buf, 8);
1557
            }
1558
        }
1559
    }
1560
  else
1561
    {
1562
      /* Registers are 32-bit.  Toss any sign-extension of the stack
1563
         pointer.  */
1564
      sp &= 0xffffffffUL;
1565
 
1566
      /* Only use the bottom half if we're in 64-bit mode.  */
1567
      if (gdbarch_ptr_bit (get_regcache_arch (regcache)) == 64)
1568
        offset = 4;
1569
 
1570
      for (i = SPARC_L0_REGNUM; i <= SPARC_I7_REGNUM; i++)
1571
        {
1572
          if (regnum == -1 || regnum == SPARC_SP_REGNUM || regnum == i)
1573
            {
1574
              regcache_raw_collect (regcache, i, buf);
1575
 
1576
              /* Handle StackGhost.  */
1577
              if (i == SPARC_I7_REGNUM)
1578
                {
1579
                  ULONGEST wcookie = sparc_fetch_wcookie (gdbarch);
1580
                  ULONGEST i7;
1581
 
1582
                  i7 = extract_unsigned_integer (buf + offset, 4, byte_order);
1583
                  store_unsigned_integer (buf + offset, 4, byte_order,
1584
                                          i7 ^ wcookie);
1585
                }
1586
 
1587
              target_write_memory (sp + ((i - SPARC_L0_REGNUM) * 4),
1588
                                   buf + offset, 4);
1589
            }
1590
        }
1591
    }
1592
}
1593
 
1594
/* Helper functions for dealing with register sets.  */
1595
 
1596
void
1597
sparc32_supply_gregset (const struct sparc_gregset *gregset,
1598
                        struct regcache *regcache,
1599
                        int regnum, const void *gregs)
1600
{
1601
  const gdb_byte *regs = gregs;
1602
  int i;
1603
 
1604
  if (regnum == SPARC32_PSR_REGNUM || regnum == -1)
1605
    regcache_raw_supply (regcache, SPARC32_PSR_REGNUM,
1606
                         regs + gregset->r_psr_offset);
1607
 
1608
  if (regnum == SPARC32_PC_REGNUM || regnum == -1)
1609
    regcache_raw_supply (regcache, SPARC32_PC_REGNUM,
1610
                         regs + gregset->r_pc_offset);
1611
 
1612
  if (regnum == SPARC32_NPC_REGNUM || regnum == -1)
1613
    regcache_raw_supply (regcache, SPARC32_NPC_REGNUM,
1614
                         regs + gregset->r_npc_offset);
1615
 
1616
  if (regnum == SPARC32_Y_REGNUM || regnum == -1)
1617
    regcache_raw_supply (regcache, SPARC32_Y_REGNUM,
1618
                         regs + gregset->r_y_offset);
1619
 
1620
  if (regnum == SPARC_G0_REGNUM || regnum == -1)
1621
    regcache_raw_supply (regcache, SPARC_G0_REGNUM, NULL);
1622
 
1623
  if ((regnum >= SPARC_G1_REGNUM && regnum <= SPARC_O7_REGNUM) || regnum == -1)
1624
    {
1625
      int offset = gregset->r_g1_offset;
1626
 
1627
      for (i = SPARC_G1_REGNUM; i <= SPARC_O7_REGNUM; i++)
1628
        {
1629
          if (regnum == i || regnum == -1)
1630
            regcache_raw_supply (regcache, i, regs + offset);
1631
          offset += 4;
1632
        }
1633
    }
1634
 
1635
  if ((regnum >= SPARC_L0_REGNUM && regnum <= SPARC_I7_REGNUM) || regnum == -1)
1636
    {
1637
      /* Not all of the register set variants include Locals and
1638
         Inputs.  For those that don't, we read them off the stack.  */
1639
      if (gregset->r_l0_offset == -1)
1640
        {
1641
          ULONGEST sp;
1642
 
1643
          regcache_cooked_read_unsigned (regcache, SPARC_SP_REGNUM, &sp);
1644
          sparc_supply_rwindow (regcache, sp, regnum);
1645
        }
1646
      else
1647
        {
1648
          int offset = gregset->r_l0_offset;
1649
 
1650
          for (i = SPARC_L0_REGNUM; i <= SPARC_I7_REGNUM; i++)
1651
            {
1652
              if (regnum == i || regnum == -1)
1653
                regcache_raw_supply (regcache, i, regs + offset);
1654
              offset += 4;
1655
            }
1656
        }
1657
    }
1658
}
1659
 
1660
void
1661
sparc32_collect_gregset (const struct sparc_gregset *gregset,
1662
                         const struct regcache *regcache,
1663
                         int regnum, void *gregs)
1664
{
1665
  gdb_byte *regs = gregs;
1666
  int i;
1667
 
1668
  if (regnum == SPARC32_PSR_REGNUM || regnum == -1)
1669
    regcache_raw_collect (regcache, SPARC32_PSR_REGNUM,
1670
                          regs + gregset->r_psr_offset);
1671
 
1672
  if (regnum == SPARC32_PC_REGNUM || regnum == -1)
1673
    regcache_raw_collect (regcache, SPARC32_PC_REGNUM,
1674
                          regs + gregset->r_pc_offset);
1675
 
1676
  if (regnum == SPARC32_NPC_REGNUM || regnum == -1)
1677
    regcache_raw_collect (regcache, SPARC32_NPC_REGNUM,
1678
                          regs + gregset->r_npc_offset);
1679
 
1680
  if (regnum == SPARC32_Y_REGNUM || regnum == -1)
1681
    regcache_raw_collect (regcache, SPARC32_Y_REGNUM,
1682
                          regs + gregset->r_y_offset);
1683
 
1684
  if ((regnum >= SPARC_G1_REGNUM && regnum <= SPARC_O7_REGNUM) || regnum == -1)
1685
    {
1686
      int offset = gregset->r_g1_offset;
1687
 
1688
      /* %g0 is always zero.  */
1689
      for (i = SPARC_G1_REGNUM; i <= SPARC_O7_REGNUM; i++)
1690
        {
1691
          if (regnum == i || regnum == -1)
1692
            regcache_raw_collect (regcache, i, regs + offset);
1693
          offset += 4;
1694
        }
1695
    }
1696
 
1697
  if ((regnum >= SPARC_L0_REGNUM && regnum <= SPARC_I7_REGNUM) || regnum == -1)
1698
    {
1699
      /* Not all of the register set variants include Locals and
1700
         Inputs.  For those that don't, we read them off the stack.  */
1701
      if (gregset->r_l0_offset != -1)
1702
        {
1703
          int offset = gregset->r_l0_offset;
1704
 
1705
          for (i = SPARC_L0_REGNUM; i <= SPARC_I7_REGNUM; i++)
1706
            {
1707
              if (regnum == i || regnum == -1)
1708
                regcache_raw_collect (regcache, i, regs + offset);
1709
              offset += 4;
1710
            }
1711
        }
1712
    }
1713
}
1714
 
1715
void
1716
sparc32_supply_fpregset (struct regcache *regcache,
1717
                         int regnum, const void *fpregs)
1718
{
1719
  const gdb_byte *regs = fpregs;
1720
  int i;
1721
 
1722
  for (i = 0; i < 32; i++)
1723
    {
1724
      if (regnum == (SPARC_F0_REGNUM + i) || regnum == -1)
1725
        regcache_raw_supply (regcache, SPARC_F0_REGNUM + i, regs + (i * 4));
1726
    }
1727
 
1728
  if (regnum == SPARC32_FSR_REGNUM || regnum == -1)
1729
    regcache_raw_supply (regcache, SPARC32_FSR_REGNUM, regs + (32 * 4) + 4);
1730
}
1731
 
1732
void
1733
sparc32_collect_fpregset (const struct regcache *regcache,
1734
                          int regnum, void *fpregs)
1735
{
1736
  gdb_byte *regs = fpregs;
1737
  int i;
1738
 
1739
  for (i = 0; i < 32; i++)
1740
    {
1741
      if (regnum == (SPARC_F0_REGNUM + i) || regnum == -1)
1742
        regcache_raw_collect (regcache, SPARC_F0_REGNUM + i, regs + (i * 4));
1743
    }
1744
 
1745
  if (regnum == SPARC32_FSR_REGNUM || regnum == -1)
1746
    regcache_raw_collect (regcache, SPARC32_FSR_REGNUM, regs + (32 * 4) + 4);
1747
}
1748
 
1749
 
1750
/* SunOS 4.  */
1751
 
1752
/* From <machine/reg.h>.  */
1753
const struct sparc_gregset sparc32_sunos4_gregset =
1754
{
1755
 
1756
  1 * 4,                        /* %pc */
1757
  2 * 4,                        /* %npc */
1758
  3 * 4,                        /* %y */
1759
  -1,                           /* %wim */
1760
  -1,                           /* %tbr */
1761
  4 * 4,                        /* %g1 */
1762
  -1                            /* %l0 */
1763
};
1764
 
1765
 
1766
/* Provide a prototype to silence -Wmissing-prototypes.  */
1767
void _initialize_sparc_tdep (void);
1768
 
1769
void
1770
_initialize_sparc_tdep (void)
1771
{
1772
  register_gdbarch_init (bfd_arch_sparc, sparc32_gdbarch_init);
1773
}

powered by: WebSVN 2.1.0

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