gdb/mn10300-tdep.c

   1 /* Target-dependent code for the Matsushita MN10300 for GDB, the GNU debugger.
   2
   3    Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free
   4    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 2 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, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 /* MVS Notes:
  24
  25    To get from 1.1 to 1.2, add:
  26    use_struct_convention
  27    store_return_value
  28    extract_return_value
  29    extract_struct_value_address
  30
  31    Make sure to use regcache.  */
  32
  33 /* MVS Notes:
  34
  35    Apparently cannot run without a stub placeholder for unwind_dummy_id.
  36 */
  37
  38 /* MVS Notes:
  39
  40    To get from 1.2 to 1.3, add:
  41    read_pc, write_pc
  42    frame_unwind_init
  43    struct mn10300_unwind_cache
  44    unwind_pc
  45    unwind_dummy_id
  46    frame_this_id
  47    frame_prev_register
  48    frame_sniffer (struct mn10300_frame_unwind)
  49 */
  50
  51 #include "defs.h"
  52 #include "arch-utils.h"
  53 #include "dis-asm.h"
  54 #include "gdbtypes.h"
  55 #include "regcache.h"
  56 #include "gdb_string.h"
  57 #include "gdb_assert.h"
  58 #include "gdbcore.h"    /* for write_memory_unsigned_integer */
  59 #include "value.h"
  60 #include "gdbtypes.h"
  61 #include "frame.h"
  62 #include "frame-unwind.h"
  63 #include "frame-base.h"
  64 #include "trad-frame.h"
  65 #include "symtab.h"
  66 #include "dwarf2-frame.h"
  67 #include "regcache.h"
  68
  69 #include "mn10300-tdep.h"
  70
  71
  72 /* Compute the alignment required by a type.  */
  73
  74 static int
  75 mn10300_type_align (struct type *type)
  76 {
  77   int i, align = 1;
  78
  79   switch (TYPE_CODE (type))
  80     {
  81     case TYPE_CODE_INT:
  82     case TYPE_CODE_ENUM:
  83     case TYPE_CODE_SET:
  84     case TYPE_CODE_RANGE:
  85     case TYPE_CODE_CHAR:
  86     case TYPE_CODE_BOOL:
  87     case TYPE_CODE_FLT:
  88     case TYPE_CODE_PTR:
  89     case TYPE_CODE_REF:
  90       return TYPE_LENGTH (type);
  91
  92     case TYPE_CODE_COMPLEX:
  93       return TYPE_LENGTH (type) / 2;
  94
  95     case TYPE_CODE_STRUCT:
  96     case TYPE_CODE_UNION:
  97       for (i = 0; i < TYPE_NFIELDS (type); i++)
  98         {
  99           int falign = mn10300_type_align (TYPE_FIELD_TYPE (type, i));
 100           while (align < falign)
 101             align <<= 1;
 102         }
 103       return align;
 104
 105     case TYPE_CODE_ARRAY:
 106       /* HACK!  Structures containing arrays, even small ones, are not
 107          elligible for returning in registers.  */
 108       return 256;
 109
 110     case TYPE_CODE_TYPEDEF:
 111       return mn10300_type_align (check_typedef (type));
 112
 113     default:
 114       internal_error (__FILE__, __LINE__, _("bad switch"));
 115     }
 116 }
 117
 118 /* MVS note this is deprecated.  */
 119 /* Should call_function allocate stack space for a struct return?  */
 120 /* gcc_p unused */
 121 static int
 122 mn10300_use_struct_convention (int gcc_p, struct type *type)
 123 {
 124   /* Structures bigger than a pair of words can't be returned in
 125      registers.  */
 126   if (TYPE_LENGTH (type) > 8)
 127     return 1;
 128
 129   switch (TYPE_CODE (type))
 130     {
 131     case TYPE_CODE_STRUCT:
 132     case TYPE_CODE_UNION:
 133       /* Structures with a single field are handled as the field
 134          itself.  */
 135       if (TYPE_NFIELDS (type) == 1)
 136         return mn10300_use_struct_convention (gcc_p,
 137                                               TYPE_FIELD_TYPE (type, 0));
 138
 139       /* Structures with word or double-word size are passed in memory, as
 140          long as they require at least word alignment.  */
 141       if (mn10300_type_align (type) >= 4)
 142         return 0;
 143
 144       return 1;
 145
 146       /* Arrays are addressable, so they're never returned in
 147          registers.  This condition can only hold when the array is
 148          the only field of a struct or union.  */
 149     case TYPE_CODE_ARRAY:
 150       return 1;
 151
 152     case TYPE_CODE_TYPEDEF:
 153       return mn10300_use_struct_convention (gcc_p, check_typedef (type));
 154
 155     default:
 156       return 0;
 157     }
 158 }
 159
 160 /* MVS note this is deprecated.  */
 161 static void
 162 mn10300_store_return_value (struct type *type,
 163                             struct regcache *regcache, const void *valbuf)
 164 {
 165   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 166   int len = TYPE_LENGTH (type);
 167   int reg, regsz;
 168
 169   if (TYPE_CODE (type) == TYPE_CODE_PTR)
 170     reg = 4;
 171   else
 172     reg = 0;
 173
 174   regsz = register_size (gdbarch, reg);
 175
 176   if (len <= regsz)
 177     regcache_raw_write_part (regcache, reg, 0, len, valbuf);
 178   else if (len <= 2 * regsz)
 179     {
 180       regcache_raw_write (regcache, reg, valbuf);
 181       gdb_assert (regsz == register_size (gdbarch, reg + 1));
 182       regcache_raw_write_part (regcache, reg+1, 0,
 183                                len - regsz, (char *) valbuf + regsz);
 184     }
 185   else
 186     internal_error (__FILE__, __LINE__,
 187                     _("Cannot store return value %d bytes long."), len);
 188 }
 189
 190 /* MVS note deprecated.  */
 191 static void
 192 mn10300_extract_return_value (struct type *type,
 193                               struct regcache *regcache, void *valbuf)
 194 {
 195   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 196   char buf[MAX_REGISTER_SIZE];
 197   int len = TYPE_LENGTH (type);
 198   int reg, regsz;
 199
 200   if (TYPE_CODE (type) == TYPE_CODE_PTR)
 201     reg = 4;
 202   else
 203     reg = 0;
 204
 205   regsz = register_size (gdbarch, reg);
 206   if (len <= regsz)
 207     {
 208       regcache_raw_read (regcache, reg, buf);
 209       memcpy (valbuf, buf, len);
 210     }
 211   else if (len <= 2 * regsz)
 212     {
 213       regcache_raw_read (regcache, reg, buf);
 214       memcpy (valbuf, buf, regsz);
 215       gdb_assert (regsz == register_size (gdbarch, reg + 1));
 216       regcache_raw_read (regcache, reg + 1, buf);
 217       memcpy ((char *) valbuf + regsz, buf, len - regsz);
 218     }
 219   else
 220     internal_error (__FILE__, __LINE__,
 221                     _("Cannot extract return value %d bytes long."), len);
 222 }
 223
 224 static char *
 225 register_name (int reg, char **regs, long sizeof_regs)
 226 {
 227   if (reg < 0 || reg >= sizeof_regs / sizeof (regs[0]))
 228     return NULL;
 229   else
 230     return regs[reg];
 231 }
 232
 233 static const char *
 234 mn10300_generic_register_name (int reg)
 235 {
 236   static char *regs[] =
 237   { "d0", "d1", "d2", "d3", "a0", "a1", "a2", "a3",
 238     "sp", "pc", "mdr", "psw", "lir", "lar", "", "",
 239     "", "", "", "", "", "", "", "",
 240     "", "", "", "", "", "", "", "fp"
 241   };
 242   return register_name (reg, regs, sizeof regs);
 243 }
 244
 245
 246 static const char *
 247 am33_register_name (int reg)
 248 {
 249   static char *regs[] =
 250   { "d0", "d1", "d2", "d3", "a0", "a1", "a2", "a3",
 251     "sp", "pc", "mdr", "psw", "lir", "lar", "",
 252     "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
 253     "ssp", "msp", "usp", "mcrh", "mcrl", "mcvf", "", "", ""
 254   };
 255   return register_name (reg, regs, sizeof regs);
 256 }
 257
 258
 259 static struct type *
 260 mn10300_register_type (struct gdbarch *gdbarch, int reg)
 261 {
 262   return builtin_type_int;
 263 }
 264
 265 static CORE_ADDR
 266 mn10300_read_pc (ptid_t ptid)
 267 {
 268   return read_register_pid (E_PC_REGNUM, ptid);
 269 }
 270
 271 static void
 272 mn10300_write_pc (CORE_ADDR val, ptid_t ptid)
 273 {
 274   return write_register_pid (E_PC_REGNUM, val, ptid);
 275 }
 276
 277 /* The breakpoint instruction must be the same size as the smallest
 278    instruction in the instruction set.
 279
 280    The Matsushita mn10x00 processors have single byte instructions
 281    so we need a single byte breakpoint.  Matsushita hasn't defined
 282    one, so we defined it ourselves.  */
 283
 284 const static unsigned char *
 285 mn10300_breakpoint_from_pc (CORE_ADDR *bp_addr, int *bp_size)
 286 {
 287   static char breakpoint[] = {0xff};
 288   *bp_size = 1;
 289   return breakpoint;
 290 }
 291
 292 /* Function: skip_prologue
 293    Return the address of the first inst past the prologue of the function.  */
 294
 295 static CORE_ADDR
 296 mn10300_skip_prologue (CORE_ADDR pc)
 297 {
 298   /* FIXME: not implemented.  */
 299   /* First approximation, try simply using skip_prologue_using_sal.  */
 300   return skip_prologue_using_sal (pc);
 301 }
 302
 303 /* Simple frame_unwind_cache.
 304    This finds the "extra info" for the frame.  */
 305 struct trad_frame_cache *
 306 mn10300_frame_unwind_cache (struct frame_info *next_frame,
 307                             void **this_prologue_cache)
 308 {
 309   struct trad_frame_cache *cache;
 310   CORE_ADDR pc;
 311
 312   if (*this_prologue_cache)
 313     return (*this_prologue_cache);
 314
 315   cache = trad_frame_cache_zalloc (next_frame);
 316   pc = gdbarch_unwind_pc (current_gdbarch, next_frame);
 317   mn10300_analyze_prologue (next_frame, (void **) &cache, pc);
 318
 319   trad_frame_set_id (cache,
 320                      frame_id_build (trad_frame_get_this_base (cache), pc));
 321
 322   (*this_prologue_cache) = cache;
 323   return cache;
 324 }
 325
 326 /* Here is a dummy implementation.  */
 327 static struct frame_id
 328 mn10300_unwind_dummy_id (struct gdbarch *gdbarch,
 329                          struct frame_info *next_frame)
 330 {
 331   return frame_id_build (frame_sp_unwind (next_frame),
 332                          frame_pc_unwind (next_frame));
 333 }
 334
 335 /* Trad frame implementation.  */
 336 static void
 337 mn10300_frame_this_id (struct frame_info *next_frame,
 338                        void **this_prologue_cache,
 339                        struct frame_id *this_id)
 340 {
 341   struct trad_frame_cache *cache =
 342     mn10300_frame_unwind_cache (next_frame, this_prologue_cache);
 343
 344   trad_frame_get_id (cache, this_id);
 345 }
 346
 347 static void
 348 mn10300_frame_prev_register (struct frame_info *next_frame,
 349                              void **this_prologue_cache,
 350                              int regnum, int *optimizedp,
 351                              enum lval_type *lvalp, CORE_ADDR *addrp,
 352                              int *realnump, void *bufferp)
 353 {
 354   struct trad_frame_cache *cache =
 355     mn10300_frame_unwind_cache (next_frame, this_prologue_cache);
 356
 357   trad_frame_get_register (cache, next_frame, regnum, optimizedp,
 358                            lvalp, addrp, realnump, bufferp);
 359   /* Or...
 360   trad_frame_get_prev_register (next_frame, cache->prev_regs, regnum,
 361                            optimizedp, lvalp, addrp, realnump, bufferp);
 362   */
 363 }
 364
 365 static const struct frame_unwind mn10300_frame_unwind = {
 366   NORMAL_FRAME,
 367   mn10300_frame_this_id,
 368   mn10300_frame_prev_register
 369 };
 370
 371 static CORE_ADDR
 372 mn10300_frame_base_address (struct frame_info *next_frame,
 373                             void **this_prologue_cache)
 374 {
 375   struct trad_frame_cache *cache =
 376     mn10300_frame_unwind_cache (next_frame, this_prologue_cache);
 377
 378   return trad_frame_get_this_base (cache);
 379 }
 380
 381 static const struct frame_unwind *
 382 mn10300_frame_sniffer (struct frame_info *next_frame)
 383 {
 384   return &mn10300_frame_unwind;
 385 }
 386
 387 static const struct frame_base mn10300_frame_base = {
 388   &mn10300_frame_unwind,
 389   mn10300_frame_base_address,
 390   mn10300_frame_base_address,
 391   mn10300_frame_base_address
 392 };
 393
 394 static CORE_ADDR
 395 mn10300_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
 396 {
 397   ULONGEST pc;
 398
 399   frame_unwind_unsigned_register (next_frame, E_PC_REGNUM, &pc);
 400   return pc;
 401 }
 402
 403 static CORE_ADDR
 404 mn10300_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
 405 {
 406   ULONGEST sp;
 407
 408   frame_unwind_unsigned_register (next_frame, E_SP_REGNUM, &sp);
 409   return sp;
 410 }
 411
 412 static void
 413 mn10300_frame_unwind_init (struct gdbarch *gdbarch)
 414 {
 415   frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
 416   frame_unwind_append_sniffer (gdbarch, mn10300_frame_sniffer);
 417   frame_base_set_default (gdbarch, &mn10300_frame_base);
 418   set_gdbarch_unwind_dummy_id (gdbarch, mn10300_unwind_dummy_id);
 419   set_gdbarch_unwind_pc (gdbarch, mn10300_unwind_pc);
 420   set_gdbarch_unwind_sp (gdbarch, mn10300_unwind_sp);
 421 }
 422
 423 /* Function: push_dummy_call
 424  *
 425  * Set up machine state for a target call, including
 426  * function arguments, stack, return address, etc.
 427  *
 428  */
 429
 430 static CORE_ADDR
 431 mn10300_push_dummy_call (struct gdbarch *gdbarch,
 432                          struct value *target_func,
 433                          struct regcache *regcache,
 434                          CORE_ADDR bp_addr,
 435                          int nargs, struct value **args,
 436                          CORE_ADDR sp,
 437                          int struct_return,
 438                          CORE_ADDR struct_addr)
 439 {
 440   const int push_size = register_size (gdbarch, E_PC_REGNUM);
 441   int regs_used = struct_return ? 1 : 0;
 442   int len, arg_len;
 443   int stack_offset = 0;
 444   int argnum;
 445   char *val;
 446
 447   /* FIXME temp, don't handle struct args at all.  */
 448   if (struct_return)
 449     error ("Target doesn't handle struct return");
 450
 451   /* This should be a nop, but align the stack just in case something
 452      went wrong.  Stacks are four byte aligned on the mn10300.  */
 453   sp &= ~3;
 454
 455   /* Now make space on the stack for the args.
 456
 457      XXX This doesn't appear to handle pass-by-invisible reference
 458      arguments.  */
 459   for (len = 0, argnum = 0; argnum < nargs; argnum++)
 460     {
 461       arg_len = (TYPE_LENGTH (value_type (args[argnum])) + 3) & ~3;
 462       if (TYPE_CODE (value_type (args[argnum])) == TYPE_CODE_STRUCT)
 463         error ("Target does not handle struct args");
 464       while (regs_used < 2 && arg_len > 0)
 465         {
 466           regs_used++;
 467           arg_len -= push_size;
 468         }
 469       len += arg_len;
 470     }
 471
 472   /* Allocate stack space.  */
 473   sp -= len;
 474
 475   regs_used = struct_return ? 1 : 0;
 476   /* Push all arguments onto the stack. */
 477   for (argnum = 0; argnum < nargs; argnum++)
 478     {
 479       /* FIXME what about structs?  */
 480       arg_len = TYPE_LENGTH (value_type (*args));
 481       val = (char *) value_contents (*args);
 482
 483       while (regs_used < 2 && arg_len > 0)
 484         {
 485           write_register (regs_used, extract_unsigned_integer (val,
 486                                                                push_size));
 487           val += push_size;
 488           arg_len -= push_size;
 489           regs_used++;
 490         }
 491
 492       while (arg_len > 0)
 493         {
 494           write_memory (sp + stack_offset, val, push_size);
 495           arg_len -= push_size;
 496           val += push_size;
 497           stack_offset += push_size;
 498         }
 499
 500       args++;
 501     }
 502
 503   /* Make space for the flushback area.  */
 504   sp -= 8;
 505
 506   /* Push the return address that contains the magic breakpoint.  */
 507   sp -= 4;
 508   write_memory_unsigned_integer (sp, push_size, bp_addr);
 509   /* Update $sp.  */
 510   regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, sp);
 511   return sp;
 512 }
 513
 514
 515 static struct gdbarch *
 516 mn10300_gdbarch_init (struct gdbarch_info info,
 517                       struct gdbarch_list *arches)
 518 {
 519   struct gdbarch *gdbarch;
 520   struct gdbarch_tdep *tdep;
 521
 522   arches = gdbarch_list_lookup_by_info (arches, &info);
 523   if (arches != NULL)
 524     return arches->gdbarch;
 525
 526   tdep = xmalloc (sizeof (struct gdbarch_tdep));
 527   gdbarch = gdbarch_alloc (&info, tdep);
 528
 529   switch (info.bfd_arch_info->mach)
 530     {
 531     case 0:
 532     case bfd_mach_mn10300:
 533       set_gdbarch_register_name (gdbarch, mn10300_generic_register_name);
 534       tdep->am33_mode = 0;
 535       break;
 536     case bfd_mach_am33:
 537       set_gdbarch_register_name (gdbarch, am33_register_name);
 538       tdep->am33_mode = 1;
 539       break;
 540     default:
 541       internal_error (__FILE__, __LINE__,
 542                       _("mn10300_gdbarch_init: Unknown mn10300 variant"));
 543       break;
 544     }
 545
 546   /* Registers.  */
 547   set_gdbarch_num_regs (gdbarch, E_NUM_REGS);
 548   set_gdbarch_register_type (gdbarch, mn10300_register_type);
 549   set_gdbarch_skip_prologue (gdbarch, mn10300_skip_prologue);
 550   set_gdbarch_read_pc (gdbarch, mn10300_read_pc);
 551   set_gdbarch_write_pc (gdbarch, mn10300_write_pc);
 552   set_gdbarch_pc_regnum (gdbarch, E_PC_REGNUM);
 553   set_gdbarch_sp_regnum (gdbarch, E_SP_REGNUM);
 554
 555   /* Stack unwinding.  */
 556   set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
 557   /* Breakpoints.  */
 558   set_gdbarch_breakpoint_from_pc (gdbarch, mn10300_breakpoint_from_pc);
 559   /* decr_pc_after_break? */
 560   /* Disassembly.  */
 561   set_gdbarch_print_insn (gdbarch, print_insn_mn10300);
 562
 563   /* Stage 2 */
 564   /* MVS Note: at least the first one is deprecated!  */
 565   set_gdbarch_deprecated_use_struct_convention (gdbarch,
 566                                                 mn10300_use_struct_convention);
 567   set_gdbarch_store_return_value (gdbarch, mn10300_store_return_value);
 568   set_gdbarch_extract_return_value (gdbarch, mn10300_extract_return_value);
 569
 570   /* Stage 3 -- get target calls working.  */
 571   set_gdbarch_push_dummy_call (gdbarch, mn10300_push_dummy_call);
 572   /* set_gdbarch_return_value (store, extract) */
 573
 574
 575   mn10300_frame_unwind_init (gdbarch);
 576
 577   return gdbarch;
 578 }
 579
 580 /* Dump out the mn10300 specific architecture information. */
 581
 582 static void
 583 mn10300_dump_tdep (struct gdbarch *current_gdbarch, struct ui_file *file)
 584 {
 585   struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
 586   fprintf_unfiltered (file, "mn10300_dump_tdep: am33_mode = %d\n",
 587                       tdep->am33_mode);
 588 }
 589
 590 void
 591 _initialize_mn10300_tdep (void)
 592 {
 593   gdbarch_register (bfd_arch_mn10300, mn10300_gdbarch_init, mn10300_dump_tdep);
 594 }
 595