gdb/config/m68k/tm-m68k.h

   1 /* Parameters for execution on a 68000 series machine.
   2    Copyright 1986, 1987, 1989, 1990, 1992, 1993, 1994, 1995, 1996, 1998,
   3    1999, 2000 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "regcache.h"
  23
  24 #define GDB_MULTI_ARCH 0
  25
  26 /* Generic 68000 stuff, to be included by other tm-*.h files.  */
  27
  28 #if !GDB_MULTI_ARCH
  29 #define TARGET_LONG_DOUBLE_FORMAT &floatformat_m68881_ext
  30
  31 #define TARGET_LONG_DOUBLE_BIT 96
  32
  33 /* Offset from address of function to start of its code.
  34    Zero on most machines.  */
  35
  36 #define FUNCTION_START_OFFSET 0
  37
  38 /* Advance PC across any function entry prologue instructions
  39    to reach some "real" code.  */
  40
  41 #if !defined(SKIP_PROLOGUE)
  42 #define SKIP_PROLOGUE(ip) (m68k_skip_prologue (ip))
  43 #endif
  44 #endif
  45 extern CORE_ADDR m68k_skip_prologue (CORE_ADDR ip);
  46
  47
  48 /* Immediately after a function call, return the saved pc.
  49    Can't always go through the frames for this because on some machines
  50    the new frame is not set up until the new function executes
  51    some instructions.  */
  52
  53 struct frame_info;
  54
  55 #if !GDB_MULTI_ARCH
  56 extern CORE_ADDR m68k_saved_pc_after_call (struct frame_info *);
  57
  58 #define SAVED_PC_AFTER_CALL(frame) \
  59   m68k_saved_pc_after_call(frame)
  60 #endif
  61
  62 /* Stack grows downward.  */
  63
  64 #if !GDB_MULTI_ARCH
  65 #define INNER_THAN(lhs,rhs) ((lhs) < (rhs))
  66
  67 /* Stack must be kept short aligned when doing function calls.  */
  68
  69 #define STACK_ALIGN(ADDR) (((ADDR) + 1) & ~1)
  70 #endif
  71
  72 /* Sequence of bytes for breakpoint instruction.
  73    This is a TRAP instruction.  The last 4 bits (0xf below) is the
  74    vector.  Systems which don't use 0xf should define BPT_VECTOR
  75    themselves before including this file.  */
  76
  77 #if !defined (BPT_VECTOR)
  78 #define BPT_VECTOR 0xf
  79 #endif
  80
  81 #if !defined (BREAKPOINT)
  82 #define BREAKPOINT {0x4e, (0x40 | BPT_VECTOR)}
  83 #endif
  84
  85 /* We default to vector 1 for the "remote" target, but allow targets
  86    to override.  */
  87 #if !defined (REMOTE_BPT_VECTOR)
  88 #define REMOTE_BPT_VECTOR 1
  89 #endif
  90
  91 #if !defined (REMOTE_BREAKPOINT)
  92 #define REMOTE_BREAKPOINT {0x4e, (0x40 | REMOTE_BPT_VECTOR)}
  93 #endif
  94
  95 /* If your kernel resets the pc after the trap happens you may need to
  96    define this before including this file.  */
  97
  98 #if !GDB_MULTI_ARCH
  99 #if !defined (DECR_PC_AFTER_BREAK)
 100 #define DECR_PC_AFTER_BREAK 2
 101 #endif
 102 #endif
 103
 104 /* Say how long (ordinary) registers are.  This is a piece of bogosity
 105    used in push_word and a few other places; REGISTER_RAW_SIZE is the
 106    real way to know how big a register is.  */
 107
 108 #if !GDB_MULTI_ARCH
 109 #define REGISTER_SIZE 4
 110 #endif
 111
 112 #define REGISTER_BYTES_FP (16*4 + 8 + 8*12 + 3*4)
 113 #define REGISTER_BYTES_NOFP (16*4 + 8)
 114
 115
 116 #ifndef NUM_REGS
 117 #define NUM_REGS 29
 118 #endif
 119
 120
 121 #define NUM_FREGS (NUM_REGS-24)
 122
 123 #if !GDB_MULTI_ARCH
 124 #ifndef REGISTER_BYTES_OK
 125 #define REGISTER_BYTES_OK(b) \
 126    ((b) == REGISTER_BYTES_FP \
 127     || (b) == REGISTER_BYTES_NOFP)
 128 #endif
 129
 130 #ifndef REGISTER_BYTES
 131 #define REGISTER_BYTES (16*4 + 8 + 8*12 + 3*4)
 132 #endif
 133 #endif //multi-arch
 134
 135 /* Index within `registers' of the first byte of the space for
 136    register N.  */
 137
 138 #if !GDB_MULTI_ARCH
 139 #define REGISTER_BYTE(N)  \
 140  ((N) >= FPC_REGNUM ? (((N) - FPC_REGNUM) * 4) + 168    \
 141   : (N) >= FP0_REGNUM ? (((N) - FP0_REGNUM) * 12) + 72  \
 142   : (N) * 4)
 143 #endif
 144
 145 /* Number of bytes of storage in the actual machine representation
 146    for register N.  On the 68000, all regs are 4 bytes
 147    except the floating point regs which are 12 bytes.  */
 148 /* Note that the unsigned cast here forces the result of the
 149    subtraction to very high positive values if N < FP0_REGNUM */
 150 #if !GDB_MULTI_ARCH
 151 #define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
 152
 153 /* Number of bytes of storage in the program's representation
 154    for register N.  On the 68000, all regs are 4 bytes
 155    except the floating point regs which are 12-byte long doubles.  */
 156
 157 #define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
 158
 159 /* Largest value REGISTER_RAW_SIZE can have.  */
 160
 161 #define MAX_REGISTER_RAW_SIZE 12
 162
 163 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 164
 165 #define MAX_REGISTER_VIRTUAL_SIZE 12
 166 #endif //multi-arch
 167
 168 /* Return the GDB type object for the "standard" data type of data
 169    in register N.  This should be int for D0-D7, long double for FP0-FP7,
 170    and void pointer for all others (A0-A7, PC, SR, FPCONTROL etc).
 171    Note, for registers which contain addresses return pointer to void,
 172    not pointer to char, because we don't want to attempt to print
 173    the string after printing the address.  */
 174 #if !GDB_MULTI_ARCH
 175 #define REGISTER_VIRTUAL_TYPE(N) \
 176   ((unsigned) (N) >= FPC_REGNUM ? lookup_pointer_type (builtin_type_void) : \
 177    (unsigned) (N) >= FP0_REGNUM ? builtin_type_long_double :                \
 178    (unsigned) (N) >=  A0_REGNUM ? lookup_pointer_type (builtin_type_void) : \
 179    builtin_type_int)
 180 #endif
 181 /* Initializer for an array of names of registers.
 182    Entries beyond the first NUM_REGS are ignored.  */
 183
 184 #if !GDB_MULTI_ARCH
 185 #define REGISTER_NAMES  \
 186  {"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7", \
 187   "a0", "a1", "a2", "a3", "a4", "a5", "fp", "sp", \
 188   "ps", "pc",  \
 189   "fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7", \
 190   "fpcontrol", "fpstatus", "fpiaddr", "fpcode", "fpflags" }
 191 #endif
 192
 193 /* Register numbers of various important registers.
 194    Note that some of these values are "real" register numbers,
 195    and correspond to the general registers of the machine,
 196    and some are "phony" register numbers which are too large
 197    to be actual register numbers as far as the user is concerned
 198    but do serve to get the desired values when passed to read_register.  */
 199
 200 #define D0_REGNUM 0
 201 #define A0_REGNUM 8
 202 #define A1_REGNUM 9
 203 #define FP_REGNUM 14            /* Contains address of executing stack frame */
 204 #define SP_REGNUM 15            /* Contains address of top of stack */
 205 #define PS_REGNUM 16            /* Contains processor status */
 206 #define PC_REGNUM 17            /* Contains program counter */
 207 #define FP0_REGNUM 18           /* Floating point register 0 */
 208 #define FPC_REGNUM 26           /* 68881 control register */
 209 #define FPS_REGNUM 27           /* 68881 status register */
 210 #define FPI_REGNUM 28           /* 68881 iaddr register */
 211
 212
 213 /* Store the address of the place in which to copy the structure the
 214    subroutine will return.  This is called from call_function. */
 215 #if !GDB_MULTI_ARCH
 216 #define STORE_STRUCT_RETURN(ADDR, SP) \
 217   { write_register (A1_REGNUM, (ADDR)); }
 218
 219 /* Extract from an array REGBUF containing the (raw) register state
 220    a function return value of type TYPE, and copy that, in virtual format,
 221    into VALBUF.  This is assuming that floating point values are returned
 222    as doubles in d0/d1.  */
 223
 224 #if !defined (DEPRECATED_EXTRACT_RETURN_VALUE)
 225 #define DEPRECATED_EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 226   memcpy ((VALBUF),                                                     \
 227           (char *)(REGBUF) +                                            \
 228                  (TYPE_LENGTH(TYPE) >= 4 ? 0 : 4 - TYPE_LENGTH(TYPE)),  \
 229           TYPE_LENGTH(TYPE))
 230 #endif
 231 #endif //multi-arch
 232
 233 /* Write into appropriate registers a function return value
 234    of type TYPE, given in virtual format.  Assumes floats are passed
 235    in d0/d1.  */
 236
 237 #if !GDB_MULTI_ARCH
 238 #if !defined (STORE_RETURN_VALUE)
 239 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 240   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 241 #endif
 242
 243 /* Extract from an array REGBUF containing the (raw) register state
 244    the address in which a function should return its structure value,
 245    as a CORE_ADDR (or an expression that can be used as one).  */
 246
 247 #define DEPRECATED_EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(CORE_ADDR *)(REGBUF))
 248 #endif //multi-arch
 249 \f
 250 /* Describe the pointer in each stack frame to the previous stack frame
 251    (its caller).  */
 252
 253 /* FRAME_CHAIN takes a frame's nominal address and produces the frame's
 254    chain-pointer.
 255    In the case of the 68000, the frame's nominal address
 256    is the address of a 4-byte word containing the calling frame's address.  */
 257
 258 /* If we are chaining from sigtramp, then manufacture a sigtramp frame
 259    (which isn't really on the stack.  I'm not sure this is right for anything
 260    but BSD4.3 on an hp300.  */
 261 #if !GDB_MULTI_ARCH
 262 #define FRAME_CHAIN(thisframe)  \
 263   (thisframe->signal_handler_caller \
 264    ? thisframe->frame \
 265    : (!inside_entry_file ((thisframe)->pc) \
 266       ? read_memory_integer ((thisframe)->frame, 4) \
 267       : 0))
 268 #endif
 269
 270 /* Define other aspects of the stack frame.  */
 271
 272 /* A macro that tells us whether the function invocation represented
 273    by FI does not have a frame on the stack associated with it.  If it
 274    does not, FRAMELESS is set to 1, else 0.  */
 275 #if !GDB_MULTI_ARCH
 276 #define FRAMELESS_FUNCTION_INVOCATION(FI) \
 277      (((FI)->signal_handler_caller) ? 0 : frameless_look_for_prologue(FI))
 278 #endif
 279
 280 /* This was determined by experimentation on hp300 BSD 4.3.  Perhaps
 281    it corresponds to some offset in /usr/include/sys/user.h or
 282    something like that.  Using some system include file would
 283    have the advantage of probably being more robust in the face
 284    of OS upgrades, but the disadvantage of being wrong for
 285    cross-debugging.  */
 286
 287 #define SIG_PC_FP_OFFSET 530
 288
 289 #if !GDB_MULTI_ARCH
 290 #define FRAME_SAVED_PC(FRAME) \
 291   (((FRAME)->signal_handler_caller \
 292     ? ((FRAME)->next \
 293        ? read_memory_integer ((FRAME)->next->frame + SIG_PC_FP_OFFSET, 4) \
 294        : read_memory_integer (read_register (SP_REGNUM) \
 295                               + SIG_PC_FP_OFFSET - 8, 4) \
 296        ) \
 297     : read_memory_integer ((FRAME)->frame + 4, 4)) \
 298    )
 299 #endif
 300
 301 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 302
 303 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 304
 305 /* Set VAL to the number of args passed to frame described by FI.
 306    Can set VAL to -1, meaning no way to tell.  */
 307
 308 /* We can't tell how many args there are
 309    now that the C compiler delays popping them.  */
 310 #if !defined (FRAME_NUM_ARGS)
 311 #define FRAME_NUM_ARGS(fi) (-1)
 312 #endif
 313
 314 /* Return number of bytes at start of arglist that are not really args.  */
 315
 316 #define FRAME_ARGS_SKIP 8
 317
 318 /* Put here the code to store, into a struct frame_saved_regs,
 319    the addresses of the saved registers of frame described by FRAME_INFO.
 320    This includes special registers such as pc and fp saved in special
 321    ways in the stack frame.  sp is even more special:
 322    the address we return for it IS the sp for the next frame.  */
 323
 324 #if !GDB_MULTI_ARCH
 325 #if !defined (FRAME_INIT_SAVED_REGS)
 326 #define FRAME_INIT_SAVED_REGS(fi) m68k_frame_init_saved_regs ((fi))
 327 void m68k_frame_init_saved_regs (struct frame_info *frame_info);
 328 #endif /* no FRAME_INIT_SAVED_REGS.  */
 329 #endif
 330 \f
 331
 332 /* Things needed for making the inferior call functions.  */
 333
 334 /* The CALL_DUMMY macro is the sequence of instructions, as disassembled
 335    by gdb itself:
 336
 337    These instructions exist only so that m68k_find_saved_regs can parse
 338    them as a "prologue"; they are never executed.
 339
 340    fmovemx fp0-fp7,sp@-                 0xf227 0xe0ff
 341    moveml d0-a5,sp@-                    0x48e7 0xfffc
 342    clrw sp@-                            0x4267
 343    movew ccr,sp@-                               0x42e7
 344
 345    The arguments are pushed at this point by GDB; no code is needed in
 346    the dummy for this.  The CALL_DUMMY_START_OFFSET gives the position
 347    of the following jsr instruction.  That is where we start
 348    executing.
 349
 350    jsr @#0x32323232                     0x4eb9 0x3232 0x3232
 351    addal #0x69696969,sp                 0xdffc 0x6969 0x6969
 352    trap #<your BPT_VECTOR number here>  0x4e4?
 353    nop                                  0x4e71
 354
 355    Note this is CALL_DUMMY_LENGTH bytes (28 for the above example).
 356
 357    The dummy frame always saves the floating-point registers, whether they
 358    actually exist on this target or not.  */
 359
 360 /* FIXME: Wrong to hardwire this as BPT_VECTOR when sometimes it
 361    should be REMOTE_BPT_VECTOR.  Best way to fix it would be to define
 362    CALL_DUMMY_BREAKPOINT_OFFSET.  */
 363 #if !GDB_MULTI_ARCH
 364 #define CALL_DUMMY {0xf227e0ff, 0x48e7fffc, 0x426742e7, 0x4eb93232, 0x3232dffc, 0x69696969, (0x4e404e71 | (BPT_VECTOR << 16))}
 365 #define CALL_DUMMY_LENGTH 28    /* Size of CALL_DUMMY */
 366 #define CALL_DUMMY_START_OFFSET 12      /* Offset to jsr instruction */
 367 #define CALL_DUMMY_BREAKPOINT_OFFSET (CALL_DUMMY_START_OFFSET + 12)
 368
 369 /* Insert the specified number of args and function address
 370    into a call sequence of the above form stored at DUMMYNAME.
 371    We use the BFD routines to store a big-endian value of known size.  */
 372
 373 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)     \
 374 { bfd_putb32 (fun,     (unsigned char *) dummyname + CALL_DUMMY_START_OFFSET + 2);  \
 375   bfd_putb32 (nargs*4, (unsigned char *) dummyname + CALL_DUMMY_START_OFFSET + 8); }
 376
 377 /* Push an empty stack frame, to record the current PC, etc.  */
 378
 379 #define PUSH_DUMMY_FRAME        { m68k_push_dummy_frame (); }
 380
 381 extern void m68k_push_dummy_frame (void);
 382
 383 extern void m68k_pop_frame (void);
 384
 385 /* Discard from the stack the innermost frame, restoring all registers.  */
 386
 387 #define POP_FRAME               { m68k_pop_frame (); }
 388 #endif
 389 /* Offset from SP to first arg on stack at first instruction of a function */
 390
 391 #define SP_ARG0 (1 * 4)
 392
 393 #define TARGET_M68K
 394
 395 /* Figure out where the longjmp will land.  Slurp the args out of the stack.
 396    We expect the first arg to be a pointer to the jmp_buf structure from which
 397    we extract the pc (JB_PC) that we will land at.  The pc is copied into ADDR.
 398    This routine returns true on success */
 399
 400 extern int m68k_get_longjmp_target (CORE_ADDR *);