gdb/tm-68k.h

   1 /* Parameters for execution on a 68000 series machine.
   2    Copyright (C) 1986, 1987, 1989, 1990 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 /* Generic 68000 stuff, to be included by other tm-*.h files.
  21    Define HAVE_68881 if that is the case.  */
  22
  23 #if defined (HAVE_68881)
  24 #define IEEE_FLOAT 1
  25 #endif
  26
  27 /* Define the bit, byte, and word ordering of the machine.  */
  28 #define TARGET_BYTE_ORDER BIG_ENDIAN
  29
  30 /* Offset from address of function to start of its code.
  31    Zero on most machines.  */
  32
  33 #define FUNCTION_START_OFFSET 0
  34
  35 /* Advance PC across any function entry prologue instructions
  36    to reach some "real" code.  */
  37
  38 #define SKIP_PROLOGUE(pc)   \
  39 { register int op = read_memory_integer (pc, 2);        \
  40   if (op == 0047126)                                    \
  41     pc += 4;   /* Skip link #word */                    \
  42   else if (op == 0044016)                               \
  43     pc += 6;   /* Skip link #long */                    \
  44   /* Not sure why branches are here.  */                \
  45   /* From m-isi.h, m-altos.h */                         \
  46   else if (op == 0060000)                               \
  47     pc += 4;   /* Skip bra #word */                     \
  48   else if (op == 00600377)                              \
  49     pc += 6;   /* skip bra #long */                     \
  50   else if ((op & 0177400) == 0060000)                   \
  51     pc += 2;   /* skip bra #char */                     \
  52 }
  53
  54 /* Immediately after a function call, return the saved pc.
  55    Can't always go through the frames for this because on some machines
  56    the new frame is not set up until the new function executes
  57    some instructions.  */
  58
  59 #define SAVED_PC_AFTER_CALL(frame) \
  60 read_memory_integer (read_register (SP_REGNUM), 4)
  61
  62 /* Stack grows downward.  */
  63
  64 #define INNER_THAN <
  65
  66 /* Sequence of bytes for breakpoint instruction.
  67    This is a TRAP instruction.  The last 4 bits (0xf below) is the
  68    vector.  Systems which don't use 0xf should define BPT_VECTOR
  69    themselves before including this file.  */
  70
  71 #if !defined BPT_VECTOR
  72 #define BPT_VECTOR 0xf
  73 #endif
  74
  75 #if !defined (BREAKPOINT)
  76 #define BREAKPOINT {0x4e, (0x40 | BPT_VECTOR)}
  77 #endif
  78
  79 /* If your kernel resets the pc after the trap happens you may need to
  80    define this before including this file.  */
  81
  82 #if !defined (DECR_PC_AFTER_BREAK)
  83 #define DECR_PC_AFTER_BREAK 2
  84 #endif
  85
  86 /* Nonzero if instruction at PC is a return instruction.  */
  87 /* Allow any of the return instructions, including a trapv and a return
  88    from interupt.  */
  89
  90 #define ABOUT_TO_RETURN(pc) ((read_memory_integer (pc, 2) & ~0x3) == 0x4e74)
  91
  92 /* Return 1 if P points to an invalid floating point value.  */
  93
  94 #define INVALID_FLOAT(p, len) 0   /* Just a first guess; not checked */
  95
  96 /* Say how long registers are.  */
  97
  98 #define REGISTER_TYPE long
  99
 100 #if defined (HAVE_68881)
 101 #  if defined (GDB_TARGET_IS_SUN3)
 102     /* Sun3 status includes fpflags, which shows whether the FPU has been used
 103        by the process, and whether the FPU was done with an instruction or
 104        was interrupted in the middle of a long instruction.  See
 105        <machine/reg.h>.  */
 106     /*                      a&d, pc,sr, fp, fpstat, fpflags   */
 107 #    define NUM_REGS 31
 108 #    define REGISTER_BYTES (16*4 + 8 + 8*12 + 3*4 + 4)
 109 #  else /* Not sun3.  */
 110 #    define NUM_REGS 29
 111 #    define REGISTER_BYTES (16*4 + 8 + 8*12 + 3*4)
 112 #  endif /* Not sun3.  */
 113 #else /* No 68881.  */
 114 #  define NUM_REGS 18
 115 #  define REGISTER_BYTES (16*4 + 8)
 116 #endif /* No 68881.  */
 117
 118 /* Index within `registers' of the first byte of the space for
 119    register N.  */
 120
 121 #if defined (HAVE_68881)
 122 #define REGISTER_BYTE(N)  \
 123  ((N) >= FPC_REGNUM ? (((N) - FPC_REGNUM) * 4) + 168    \
 124   : (N) >= FP0_REGNUM ? (((N) - FP0_REGNUM) * 12) + 72  \
 125   : (N) * 4)
 126
 127 /* Number of bytes of storage in the actual machine representation
 128    for register N.  On the 68000, all regs are 4 bytes
 129    except the floating point regs which are 12 bytes.  */
 130 /* Note that the unsigned cast here forces the result of the
 131    subtraction to very high positive values if N < FP0_REGNUM */
 132
 133 #define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
 134
 135 /* Number of bytes of storage in the program's representation
 136    for register N.  On the 68000, all regs are 4 bytes
 137    except the floating point regs which are 8-byte doubles.  */
 138
 139 #define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 8 : 4)
 140
 141 /* Largest value REGISTER_RAW_SIZE can have.  */
 142
 143 #define MAX_REGISTER_RAW_SIZE 12
 144
 145 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 146
 147 #define MAX_REGISTER_VIRTUAL_SIZE 8
 148
 149 /* Nonzero if register N requires conversion
 150    from raw format to virtual format.  */
 151
 152 #define REGISTER_CONVERTIBLE(N) (((unsigned)(N) - FP0_REGNUM) < 8)
 153
 154 /* Put the declaration out here because if it's in the macros, PCC
 155    will complain.  */
 156 extern struct ext_format ext_format_68881;
 157
 158 /* Convert data from raw format for register REGNUM
 159    to virtual format for register REGNUM.  */
 160
 161 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO)     \
 162 { \
 163   if ((REGNUM) >= FP0_REGNUM && (REGNUM) < FPC_REGNUM)  \
 164     ieee_extended_to_double (&ext_format_68881, (FROM), (double *)(TO)); \
 165   else                                  \
 166     bcopy ((FROM), (TO), 4);    \
 167 }
 168
 169 /* Convert data from virtual format for register REGNUM
 170    to raw format for register REGNUM.  */
 171
 172 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
 173 { \
 174   if ((REGNUM) >= FP0_REGNUM && (REGNUM) < FPC_REGNUM)  \
 175     double_to_ieee_extended (&ext_format_68881, (double *)(FROM), (TO)); \
 176   else                                  \
 177     bcopy ((FROM), (TO), 4);    \
 178 }
 179
 180 /* Return the GDB type object for the "standard" data type
 181    of data in register N.  */
 182 /* Note, for registers which contain addresses return
 183    pointer to void, not pointer to char, because we don't
 184    want to attempt to print the string after printing the address.  */
 185 #define REGISTER_VIRTUAL_TYPE(N) \
 186  (((unsigned)(N) - FP0_REGNUM) < 8 ? builtin_type_double :           \
 187   (N) == PC_REGNUM || (N) == FP_REGNUM || (N) == SP_REGNUM ?         \
 188   lookup_pointer_type (builtin_type_void) : builtin_type_int)
 189
 190 #else /* no 68881.  */
 191 /* Index within `registers' of the first byte of the space for
 192    register N.  */
 193
 194 #define REGISTER_BYTE(N)  ((N) * 4)
 195
 196 /* Number of bytes of storage in the actual machine representation
 197    for register N.  On the 68000, all regs are 4 bytes.  */
 198
 199 #define REGISTER_RAW_SIZE(N) 4
 200
 201 /* Number of bytes of storage in the program's representation
 202    for register N.  On the 68000, all regs are 4 bytes.  */
 203
 204 #define REGISTER_VIRTUAL_SIZE(N) 4
 205
 206 /* Largest value REGISTER_RAW_SIZE can have.  */
 207
 208 #define MAX_REGISTER_RAW_SIZE 4
 209
 210 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 211
 212 #define MAX_REGISTER_VIRTUAL_SIZE 4
 213
 214 /* Nonzero if register N requires conversion
 215    from raw format to virtual format.  */
 216
 217 #define REGISTER_CONVERTIBLE(N) 0
 218
 219 /* Convert data from raw format for register REGNUM
 220    to virtual format for register REGNUM.  */
 221
 222 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO)  bcopy ((FROM), (TO), 4);
 223
 224 /* Convert data from virtual format for register REGNUM
 225    to raw format for register REGNUM.  */
 226
 227 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO)  bcopy ((FROM), (TO), 4);
 228
 229 /* Return the GDB type object for the "standard" data type
 230    of data in register N.  */
 231
 232 #define REGISTER_VIRTUAL_TYPE(N)  builtin_type_int
 233
 234 #endif /* No 68881.  */
 235
 236 /* Initializer for an array of names of registers.
 237    Entries beyond the first NUM_REGS are ignored.  */
 238
 239 #define REGISTER_NAMES  \
 240  {"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7", \
 241   "a0", "a1", "a2", "a3", "a4", "a5", "fp", "sp", \
 242   "ps", "pc",  \
 243   "fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7", \
 244   "fpcontrol", "fpstatus", "fpiaddr", "fpcode", "fpflags" }
 245
 246 /* Register numbers of various important registers.
 247    Note that some of these values are "real" register numbers,
 248    and correspond to the general registers of the machine,
 249    and some are "phony" register numbers which are too large
 250    to be actual register numbers as far as the user is concerned
 251    but do serve to get the desired values when passed to read_register.  */
 252
 253 #define A1_REGNUM 9
 254 #define FP_REGNUM 14            /* Contains address of executing stack frame */
 255 #define SP_REGNUM 15            /* Contains address of top of stack */
 256 #define PS_REGNUM 16            /* Contains processor status */
 257 #define PC_REGNUM 17            /* Contains program counter */
 258 #if defined (HAVE_68881)
 259 #define FP0_REGNUM 18           /* Floating point register 0 */
 260 #define FPC_REGNUM 26           /* 68881 control register */
 261 #define FPS_REGNUM 27           /* 68881 status register */
 262 #define FPI_REGNUM 28           /* 68881 iaddr register */
 263 #endif /* 68881.  */
 264
 265 /* Store the address of the place in which to copy the structure the
 266    subroutine will return.  This is called from call_function. */
 267
 268 #define STORE_STRUCT_RETURN(ADDR, SP) \
 269   { write_register (A1_REGNUM, (ADDR)); }
 270
 271 /* Extract from an array REGBUF containing the (raw) register state
 272    a function return value of type TYPE, and copy that, in virtual format,
 273    into VALBUF.  This is assuming that floating point values are returned
 274    as doubles in d0/d1.  */
 275
 276 #if !defined (EXTRACT_RETURN_VALUE)
 277 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 278   bcopy ((char *)(REGBUF) +                                             \
 279                  (TYPE_LENGTH(TYPE) >= 4 ? 0 : 4 - TYPE_LENGTH(TYPE)),  \
 280          VALBUF, TYPE_LENGTH(TYPE))
 281 #endif
 282
 283 /* Write into appropriate registers a function return value
 284    of type TYPE, given in virtual format.  Assumes floats are passed
 285    in d0/d1.  */
 286
 287 #if !defined (STORE_RETURN_VALUE)
 288 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 289   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 290 #endif
 291
 292 /* Extract from an array REGBUF containing the (raw) register state
 293    the address in which a function should return its structure value,
 294    as a CORE_ADDR (or an expression that can be used as one).  */
 295
 296 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(CORE_ADDR *)(REGBUF))
 297 \f
 298 /* Describe the pointer in each stack frame to the previous stack frame
 299    (its caller).  */
 300
 301 /* FRAME_CHAIN takes a frame's nominal address
 302    and produces the frame's chain-pointer.
 303
 304    FRAME_CHAIN_COMBINE takes the chain pointer and the frame's nominal address
 305    and produces the nominal address of the caller frame.
 306
 307    However, if FRAME_CHAIN_VALID returns zero,
 308    it means the given frame is the outermost one and has no caller.
 309    In that case, FRAME_CHAIN_COMBINE is not used.  */
 310
 311 /* In the case of the 68000, the frame's nominal address
 312    is the address of a 4-byte word containing the calling frame's address.  */
 313
 314 #define FRAME_CHAIN(thisframe)  \
 315   (outside_startup_file ((thisframe)->pc) ? \
 316    read_memory_integer ((thisframe)->frame, 4) :\
 317    0)
 318
 319 #if defined (FRAME_CHAIN_VALID_ALTERNATE)
 320
 321 /* Use the alternate method of avoiding running up off the end of
 322    the frame chain or following frames back into the startup code.
 323    See the comments in blockframe.c */
 324
 325 #define FRAME_CHAIN_VALID(chain, thisframe)     \
 326   (chain != 0                                   \
 327    && !(inside_main_scope ((thisframe)->pc))    \
 328    && !(inside_entry_scope ((thisframe)->pc)))
 329
 330 #else
 331
 332 #define FRAME_CHAIN_VALID(chain, thisframe) \
 333   (chain != 0 && outside_startup_file (FRAME_SAVED_PC (thisframe)))
 334
 335 #endif  /* FRAME_CHAIN_VALID_ALTERNATE */
 336
 337 #define FRAME_CHAIN_COMBINE(chain, thisframe) (chain)
 338
 339 /* Define other aspects of the stack frame.  */
 340
 341 /* A macro that tells us whether the function invocation represented
 342    by FI does not have a frame on the stack associated with it.  If it
 343    does not, FRAMELESS is set to 1, else 0.  */
 344 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 345   (FRAMELESS) = frameless_look_for_prologue(FI)
 346
 347 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 4, 4))
 348
 349 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 350
 351 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 352
 353 /* Set VAL to the number of args passed to frame described by FI.
 354    Can set VAL to -1, meaning no way to tell.  */
 355
 356 /* We can't tell how many args there are
 357    now that the C compiler delays popping them.  */
 358 #if !defined (FRAME_NUM_ARGS)
 359 #define FRAME_NUM_ARGS(val,fi) (val = -1)
 360 #endif
 361
 362 /* Return number of bytes at start of arglist that are not really args.  */
 363
 364 #define FRAME_ARGS_SKIP 8
 365
 366 /* Put here the code to store, into a struct frame_saved_regs,
 367    the addresses of the saved registers of frame described by FRAME_INFO.
 368    This includes special registers such as pc and fp saved in special
 369    ways in the stack frame.  sp is even more special:
 370    the address we return for it IS the sp for the next frame.  */
 371
 372 #if !defined (FRAME_FIND_SAVED_REGS)
 373 #if defined (HAVE_68881)
 374 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs)             \
 375 { register int regnum;                                                  \
 376   register int regmask;                                                 \
 377   register CORE_ADDR next_addr;                                         \
 378   register CORE_ADDR pc;                                                \
 379   int nextinsn;                                                         \
 380   bzero (&frame_saved_regs, sizeof frame_saved_regs);                   \
 381   if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4 \
 382       && (frame_info)->pc <= (frame_info)->frame)                               \
 383     { next_addr = (frame_info)->frame;                                  \
 384       pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4; }\
 385   else                                                                  \
 386     { pc = get_pc_function_start ((frame_info)->pc);                    \
 387       /* Verify we have a link a6 instruction next;                     \
 388          if not we lose.  If we win, find the address above the saved   \
 389          regs using the amount of storage from the link instruction.  */\
 390       if (044016 == read_memory_integer (pc, 2))                        \
 391         next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 4), pc+=4; \
 392       else if (047126 == read_memory_integer (pc, 2))                   \
 393         next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 2), pc+=2; \
 394       else goto lose;                                                   \
 395       /* If have an addal #-n, sp next, adjust next_addr.  */           \
 396       if ((0177777 & read_memory_integer (pc, 2)) == 0157774)           \
 397         next_addr += read_memory_integer (pc += 2, 4), pc += 4;         \
 398     }                                                                   \
 399   /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */      \
 400   regmask = read_memory_integer (pc + 2, 2);                            \
 401   /* But before that can come an fmovem.  Check for it.  */             \
 402   nextinsn = 0xffff & read_memory_integer (pc, 2);                      \
 403   if (0xf227 == nextinsn                                                \
 404       && (regmask & 0xff00) == 0xe000)                                  \
 405     { pc += 4; /* Regmask's low bit is for register fp7, the first pushed */ \
 406       for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--, regmask >>= 1)              \
 407         if (regmask & 1)                                                \
 408           (frame_saved_regs).regs[regnum] = (next_addr -= 12);          \
 409       regmask = read_memory_integer (pc + 2, 2); }                      \
 410   if (0044327 == read_memory_integer (pc, 2))                           \
 411     { pc += 4; /* Regmask's low bit is for register 0, the first written */ \
 412       for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)            \
 413         if (regmask & 1)                                                \
 414           (frame_saved_regs).regs[regnum] = (next_addr += 4) - 4; }     \
 415   else if (0044347 == read_memory_integer (pc, 2))                      \
 416     { pc += 4; /* Regmask's low bit is for register 15, the first pushed */ \
 417       for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1)           \
 418         if (regmask & 1)                                                \
 419           (frame_saved_regs).regs[regnum] = (next_addr -= 4); }         \
 420   else if (0x2f00 == (0xfff0 & read_memory_integer (pc, 2)))            \
 421     { regnum = 0xf & read_memory_integer (pc, 2); pc += 2;              \
 422       (frame_saved_regs).regs[regnum] = (next_addr -= 4); }             \
 423   /* fmovemx to index of sp may follow.  */                             \
 424   regmask = read_memory_integer (pc + 2, 2);                            \
 425   nextinsn = 0xffff & read_memory_integer (pc, 2);                      \
 426   if (0xf236 == nextinsn                                                \
 427       && (regmask & 0xff00) == 0xf000)                                  \
 428     { pc += 10; /* Regmask's low bit is for register fp0, the first written */ \
 429       for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--, regmask >>= 1)              \
 430         if (regmask & 1)                                                \
 431           (frame_saved_regs).regs[regnum] = (next_addr += 12) - 12;     \
 432       regmask = read_memory_integer (pc + 2, 2); }                      \
 433   /* clrw -(sp); movw ccr,-(sp) may follow.  */                         \
 434   if (0x426742e7 == read_memory_integer (pc, 4))                        \
 435     (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4);              \
 436   lose: ;                                                               \
 437   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8;         \
 438   (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame;             \
 439   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4;         \
 440 }
 441 #else /* no 68881.  */
 442 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs)             \
 443 { register int regnum;                                                  \
 444   register int regmask;                                                 \
 445   register CORE_ADDR next_addr;                                         \
 446   register CORE_ADDR pc;                                                \
 447   bzero (&frame_saved_regs, sizeof frame_saved_regs);                   \
 448   if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 4 \
 449       && (frame_info)->pc <= (frame_info)->frame)                               \
 450     { next_addr = (frame_info)->frame;                                  \
 451       pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 4; }\
 452   else                                                                  \
 453     { pc = get_pc_function_start ((frame_info)->pc);                    \
 454       /* Verify we have a link a6 instruction next;                     \
 455          if not we lose.  If we win, find the address above the saved   \
 456          regs using the amount of storage from the link instruction.  */\
 457       if (044016 == read_memory_integer (pc, 2))                        \
 458         next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 4), pc+=4; \
 459       else if (047126 == read_memory_integer (pc, 2))                   \
 460         next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 2), pc+=2; \
 461       else goto lose;                                                   \
 462       /* If have an addal #-n, sp next, adjust next_addr.  */           \
 463       if ((0177777 & read_memory_integer (pc, 2)) == 0157774)           \
 464         next_addr += read_memory_integer (pc += 2, 4), pc += 4;         \
 465     }                                                                   \
 466   /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */      \
 467   regmask = read_memory_integer (pc + 2, 2);                            \
 468   if (0044327 == read_memory_integer (pc, 2))                           \
 469     { pc += 4; /* Regmask's low bit is for register 0, the first written */ \
 470       for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)            \
 471         if (regmask & 1)                                                \
 472           (frame_saved_regs).regs[regnum] = (next_addr += 4) - 4; }     \
 473   else if (0044347 == read_memory_integer (pc, 2))                      \
 474     { pc += 4; /* Regmask's low bit is for register 15, the first pushed */ \
 475       for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1)           \
 476         if (regmask & 1)                                                \
 477           (frame_saved_regs).regs[regnum] = (next_addr -= 4); }         \
 478   else if (0x2f00 == 0xfff0 & read_memory_integer (pc, 2))              \
 479     { regnum = 0xf & read_memory_integer (pc, 2); pc += 2;              \
 480       (frame_saved_regs).regs[regnum] = (next_addr -= 4); }             \
 481   /* clrw -(sp); movw ccr,-(sp) may follow.  */                         \
 482   if (0x426742e7 == read_memory_integer (pc, 4))                        \
 483     (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4);              \
 484   lose: ;                                                               \
 485   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8;         \
 486   (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame;             \
 487   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4;         \
 488 }
 489 #endif /* no 68881.  */
 490 #endif /* no FIND_FRAME_SAVED_REGS.  */
 491
 492 \f
 493 /* Things needed for making the inferior call functions.
 494    It seems like every m68k based machine has almost identical definitions
 495    in the individual machine's configuration files.  Most other cpu types
 496    (mips, i386, etc) have routines in their *-tdep.c files to handle this
 497    for most configurations.  The m68k family should be able to do this as
 498    well.  These macros can still be overridden when necessary.  */
 499
 500 /* The CALL_DUMMY macro is the sequence of instructions, as disassembled
 501    by gdb itself:
 502
 503         fmovemx fp0-fp7,sp@-                    0xf227 0xe0ff
 504         moveml d0-a5,sp@-                       0x48e7 0xfffc
 505         clrw sp@-                               0x4267
 506         movew ccr,sp@-                          0x42e7
 507
 508         /..* The arguments are pushed at this point by GDB;
 509         no code is needed in the dummy for this.
 510         The CALL_DUMMY_START_OFFSET gives the position of
 511         the following jsr instruction.  *../
 512
 513         jsr @#0x32323232                        0x4eb9 0x3232 0x3232
 514         addal #0x69696969,sp                    0xdffc 0x6969 0x6969
 515         trap #<your BPT_VECTOR number here>     0x4e4?
 516         nop                                     0x4e71
 517
 518    Note this is CALL_DUMMY_LENGTH bytes (28 for the above example).
 519    We actually start executing at the jsr, since the pushing of the
 520    registers is done by PUSH_DUMMY_FRAME.  If this were real code,
 521    the arguments for the function called by the jsr would be pushed
 522    between the moveml and the jsr, and we could allow it to execute through.
 523    But the arguments have to be pushed by GDB after the PUSH_DUMMY_FRAME is
 524    done, and we cannot allow the moveml to push the registers again lest
 525    they be taken for the arguments.  */
 526
 527 #if defined (HAVE_68881)
 528
 529 #define CALL_DUMMY {0xf227e0ff, 0x48e7fffc, 0x426742e7, 0x4eb93232, 0x3232dffc, 0x69696969, (0x4e404e71 | (BPT_VECTOR << 16))}
 530 #define CALL_DUMMY_LENGTH 28            /* Size of CALL_DUMMY */
 531 #define CALL_DUMMY_START_OFFSET 12      /* Offset to jsr instruction*/
 532
 533 #else
 534
 535 #define CALL_DUMMY {0x48e7fffc, 0x426742e7, 0x4eb93232, 0x3232dffc, 0x69696969, (0x4e404e71 | (BPT_VECTOR << 16))}
 536 #define CALL_DUMMY_LENGTH 24            /* Size of CALL_DUMMY */
 537 #define CALL_DUMMY_START_OFFSET 8       /* Offset to jsr instruction*/
 538
 539 #endif  /* HAVE_68881 */
 540
 541 /* Insert the specified number of args and function address
 542    into a call sequence of the above form stored at DUMMYNAME.  */
 543
 544 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)     \
 545 { *(int *)((char *) dummyname + CALL_DUMMY_START_OFFSET + 2) = fun;  \
 546   *(int *)((char *) dummyname + CALL_DUMMY_START_OFFSET + 8) = nargs * 4; }
 547
 548 /* Push an empty stack frame, to record the current PC, etc.  */
 549
 550 #define PUSH_DUMMY_FRAME        { m68k_push_dummy_frame (); }
 551
 552 /* Discard from the stack the innermost frame, restoring all registers.  */
 553
 554 #define POP_FRAME               { m68k_pop_frame (); }
 555