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 !defined (DECR_PC_AFTER_BREAK)
  99 #define DECR_PC_AFTER_BREAK 2
 100 #endif
 101
 102 /* Say how long (ordinary) registers are.  This is a piece of bogosity
 103    used in push_word and a few other places; REGISTER_RAW_SIZE is the
 104    real way to know how big a register is.  */
 105
 106 #if !GDB_MULTI_ARCH
 107 #define REGISTER_SIZE 4
 108 #endif
 109
 110 #define REGISTER_BYTES_FP (16*4 + 8 + 8*12 + 3*4)
 111 #define REGISTER_BYTES_NOFP (16*4 + 8)
 112
 113 #ifndef NUM_REGS
 114 #define NUM_REGS 29
 115 #endif
 116
 117 #define NUM_FREGS (NUM_REGS-24)
 118
 119 #ifndef REGISTER_BYTES_OK
 120 #define REGISTER_BYTES_OK(b) \
 121    ((b) == REGISTER_BYTES_FP \
 122     || (b) == REGISTER_BYTES_NOFP)
 123 #endif
 124
 125 #ifndef REGISTER_BYTES
 126 #define REGISTER_BYTES (16*4 + 8 + 8*12 + 3*4)
 127 #endif
 128
 129 /* Index within `registers' of the first byte of the space for
 130    register N.  */
 131
 132 #if !GDB_MULTI_ARCH
 133 #define REGISTER_BYTE(N)  \
 134  ((N) >= FPC_REGNUM ? (((N) - FPC_REGNUM) * 4) + 168    \
 135   : (N) >= FP0_REGNUM ? (((N) - FP0_REGNUM) * 12) + 72  \
 136   : (N) * 4)
 137 #endif
 138
 139 /* Number of bytes of storage in the actual machine representation
 140    for register N.  On the 68000, all regs are 4 bytes
 141    except the floating point regs which are 12 bytes.  */
 142 /* Note that the unsigned cast here forces the result of the
 143    subtraction to very high positive values if N < FP0_REGNUM */
 144 #if !GDB_MULTI_ARCH
 145 #define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
 146
 147 /* Number of bytes of storage in the program's representation
 148    for register N.  On the 68000, all regs are 4 bytes
 149    except the floating point regs which are 12-byte long doubles.  */
 150
 151 #define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
 152
 153 /* Largest value REGISTER_RAW_SIZE can have.  */
 154
 155 #define MAX_REGISTER_RAW_SIZE 12
 156
 157 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 158
 159 #define MAX_REGISTER_VIRTUAL_SIZE 12
 160 #endif
 161 /* Return the GDB type object for the "standard" data type of data
 162    in register N.  This should be int for D0-D7, long double for FP0-FP7,
 163    and void pointer for all others (A0-A7, PC, SR, FPCONTROL etc).
 164    Note, for registers which contain addresses return pointer to void,
 165    not pointer to char, because we don't want to attempt to print
 166    the string after printing the address.  */
 167 #if !GDB_MULTI_ARCH
 168 #define REGISTER_VIRTUAL_TYPE(N) \
 169   ((unsigned) (N) >= FPC_REGNUM ? lookup_pointer_type (builtin_type_void) : \
 170    (unsigned) (N) >= FP0_REGNUM ? builtin_type_long_double :                \
 171    (unsigned) (N) >=  A0_REGNUM ? lookup_pointer_type (builtin_type_void) : \
 172    builtin_type_int)
 173 #endif
 174 /* Initializer for an array of names of registers.
 175    Entries beyond the first NUM_REGS are ignored.  */
 176
 177 #if !GDB_MULTI_ARCH
 178 #define REGISTER_NAMES  \
 179  {"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7", \
 180   "a0", "a1", "a2", "a3", "a4", "a5", "fp", "sp", \
 181   "ps", "pc",  \
 182   "fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7", \
 183   "fpcontrol", "fpstatus", "fpiaddr", "fpcode", "fpflags" }
 184 #endif
 185
 186 /* Register numbers of various important registers.
 187    Note that some of these values are "real" register numbers,
 188    and correspond to the general registers of the machine,
 189    and some are "phony" register numbers which are too large
 190    to be actual register numbers as far as the user is concerned
 191    but do serve to get the desired values when passed to read_register.  */
 192
 193 #define D0_REGNUM 0
 194 #define A0_REGNUM 8
 195 #define A1_REGNUM 9
 196 #define FP_REGNUM 14            /* Contains address of executing stack frame */
 197 #define SP_REGNUM 15            /* Contains address of top of stack */
 198 #define PS_REGNUM 16            /* Contains processor status */
 199 #define PC_REGNUM 17            /* Contains program counter */
 200 #define FP0_REGNUM 18           /* Floating point register 0 */
 201 #define FPC_REGNUM 26           /* 68881 control register */
 202 #define FPS_REGNUM 27           /* 68881 status register */
 203 #define FPI_REGNUM 28           /* 68881 iaddr register */
 204
 205
 206 /* Store the address of the place in which to copy the structure the
 207    subroutine will return.  This is called from call_function. */
 208
 209 #define STORE_STRUCT_RETURN(ADDR, SP) \
 210   { write_register (A1_REGNUM, (ADDR)); }
 211
 212 /* Extract from an array REGBUF containing the (raw) register state
 213    a function return value of type TYPE, and copy that, in virtual format,
 214    into VALBUF.  This is assuming that floating point values are returned
 215    as doubles in d0/d1.  */
 216
 217 #if !defined (DEPRECATED_EXTRACT_RETURN_VALUE)
 218 #define DEPRECATED_EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 219   memcpy ((VALBUF),                                                     \
 220           (char *)(REGBUF) +                                            \
 221                  (TYPE_LENGTH(TYPE) >= 4 ? 0 : 4 - TYPE_LENGTH(TYPE)),  \
 222           TYPE_LENGTH(TYPE))
 223 #endif
 224
 225 /* Write into appropriate registers a function return value
 226    of type TYPE, given in virtual format.  Assumes floats are passed
 227    in d0/d1.  */
 228
 229 #if !defined (STORE_RETURN_VALUE)
 230 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 231   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 232 #endif
 233
 234 /* Extract from an array REGBUF containing the (raw) register state
 235    the address in which a function should return its structure value,
 236    as a CORE_ADDR (or an expression that can be used as one).  */
 237
 238 #define DEPRECATED_EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(CORE_ADDR *)(REGBUF))
 239 \f
 240 /* Describe the pointer in each stack frame to the previous stack frame
 241    (its caller).  */
 242
 243 /* FRAME_CHAIN takes a frame's nominal address and produces the frame's
 244    chain-pointer.
 245    In the case of the 68000, the frame's nominal address
 246    is the address of a 4-byte word containing the calling frame's address.  */
 247
 248 /* If we are chaining from sigtramp, then manufacture a sigtramp frame
 249    (which isn't really on the stack.  I'm not sure this is right for anything
 250    but BSD4.3 on an hp300.  */
 251 #define FRAME_CHAIN(thisframe)  \
 252   (thisframe->signal_handler_caller \
 253    ? thisframe->frame \
 254    : (!inside_entry_file ((thisframe)->pc) \
 255       ? read_memory_integer ((thisframe)->frame, 4) \
 256       : 0))
 257
 258 /* Define other aspects of the stack frame.  */
 259
 260 /* A macro that tells us whether the function invocation represented
 261    by FI does not have a frame on the stack associated with it.  If it
 262    does not, FRAMELESS is set to 1, else 0.  */
 263 #define FRAMELESS_FUNCTION_INVOCATION(FI) \
 264      (((FI)->signal_handler_caller) ? 0 : frameless_look_for_prologue(FI))
 265
 266 /* This was determined by experimentation on hp300 BSD 4.3.  Perhaps
 267    it corresponds to some offset in /usr/include/sys/user.h or
 268    something like that.  Using some system include file would
 269    have the advantage of probably being more robust in the face
 270    of OS upgrades, but the disadvantage of being wrong for
 271    cross-debugging.  */
 272
 273 #define SIG_PC_FP_OFFSET 530
 274
 275 #define FRAME_SAVED_PC(FRAME) \
 276   (((FRAME)->signal_handler_caller \
 277     ? ((FRAME)->next \
 278        ? read_memory_integer ((FRAME)->next->frame + SIG_PC_FP_OFFSET, 4) \
 279        : read_memory_integer (read_register (SP_REGNUM) \
 280                               + SIG_PC_FP_OFFSET - 8, 4) \
 281        ) \
 282     : read_memory_integer ((FRAME)->frame + 4, 4)) \
 283    )
 284
 285 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 286
 287 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 288
 289 /* Set VAL to the number of args passed to frame described by FI.
 290    Can set VAL to -1, meaning no way to tell.  */
 291
 292 /* We can't tell how many args there are
 293    now that the C compiler delays popping them.  */
 294 #if !defined (FRAME_NUM_ARGS)
 295 #define FRAME_NUM_ARGS(fi) (-1)
 296 #endif
 297
 298 /* Return number of bytes at start of arglist that are not really args.  */
 299
 300 #define FRAME_ARGS_SKIP 8
 301
 302 /* Put here the code to store, into a struct frame_saved_regs,
 303    the addresses of the saved registers of frame described by FRAME_INFO.
 304    This includes special registers such as pc and fp saved in special
 305    ways in the stack frame.  sp is even more special:
 306    the address we return for it IS the sp for the next frame.  */
 307
 308 #if !GDB_MULTI_ARCH
 309 #if !defined (FRAME_INIT_SAVED_REGS)
 310 #define FRAME_INIT_SAVED_REGS(fi) m68k_frame_init_saved_regs ((fi))
 311 void m68k_frame_init_saved_regs (struct frame_info *frame_info);
 312 #endif /* no FRAME_INIT_SAVED_REGS.  */
 313 #endif
 314 \f
 315
 316 /* Things needed for making the inferior call functions.  */
 317
 318 /* The CALL_DUMMY macro is the sequence of instructions, as disassembled
 319    by gdb itself:
 320
 321    These instructions exist only so that m68k_find_saved_regs can parse
 322    them as a "prologue"; they are never executed.
 323
 324    fmovemx fp0-fp7,sp@-                 0xf227 0xe0ff
 325    moveml d0-a5,sp@-                    0x48e7 0xfffc
 326    clrw sp@-                            0x4267
 327    movew ccr,sp@-                               0x42e7
 328
 329    The arguments are pushed at this point by GDB; no code is needed in
 330    the dummy for this.  The CALL_DUMMY_START_OFFSET gives the position
 331    of the following jsr instruction.  That is where we start
 332    executing.
 333
 334    jsr @#0x32323232                     0x4eb9 0x3232 0x3232
 335    addal #0x69696969,sp                 0xdffc 0x6969 0x6969
 336    trap #<your BPT_VECTOR number here>  0x4e4?
 337    nop                                  0x4e71
 338
 339    Note this is CALL_DUMMY_LENGTH bytes (28 for the above example).
 340
 341    The dummy frame always saves the floating-point registers, whether they
 342    actually exist on this target or not.  */
 343
 344 /* FIXME: Wrong to hardwire this as BPT_VECTOR when sometimes it
 345    should be REMOTE_BPT_VECTOR.  Best way to fix it would be to define
 346    CALL_DUMMY_BREAKPOINT_OFFSET.  */
 347 #if !GDB_MULTI_ARCH
 348 #define CALL_DUMMY {0xf227e0ff, 0x48e7fffc, 0x426742e7, 0x4eb93232, 0x3232dffc, 0x69696969, (0x4e404e71 | (BPT_VECTOR << 16))}
 349 #define CALL_DUMMY_LENGTH 28    /* Size of CALL_DUMMY */
 350 #define CALL_DUMMY_START_OFFSET 12      /* Offset to jsr instruction */
 351 #define CALL_DUMMY_BREAKPOINT_OFFSET (CALL_DUMMY_START_OFFSET + 12)
 352
 353 /* Insert the specified number of args and function address
 354    into a call sequence of the above form stored at DUMMYNAME.
 355    We use the BFD routines to store a big-endian value of known size.  */
 356
 357 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)     \
 358 { bfd_putb32 (fun,     (unsigned char *) dummyname + CALL_DUMMY_START_OFFSET + 2);  \
 359   bfd_putb32 (nargs*4, (unsigned char *) dummyname + CALL_DUMMY_START_OFFSET + 8); }
 360
 361 /* Push an empty stack frame, to record the current PC, etc.  */
 362
 363 #define PUSH_DUMMY_FRAME        { m68k_push_dummy_frame (); }
 364
 365 extern void m68k_push_dummy_frame (void);
 366
 367 extern void m68k_pop_frame (void);
 368
 369 /* Discard from the stack the innermost frame, restoring all registers.  */
 370
 371 #define POP_FRAME               { m68k_pop_frame (); }
 372 #endif
 373 /* Offset from SP to first arg on stack at first instruction of a function */
 374
 375 #define SP_ARG0 (1 * 4)
 376
 377 #define TARGET_M68K
 378
 379 /* Figure out where the longjmp will land.  Slurp the args out of the stack.
 380    We expect the first arg to be a pointer to the jmp_buf structure from which
 381    we extract the pc (JB_PC) that we will land at.  The pc is copied into ADDR.
 382    This routine returns true on success */
 383
 384 extern int m68k_get_longjmp_target (CORE_ADDR *);