gdb/tm-merlin.h

   1 /* Definitions to target GDB to a merlin under utek 2.1
   2    Copyright (C) 1986, 1987, 1989, 1991 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 #define TARGET_BYTE_ORDER LITTLE_ENDIAN
  21
  22 /* I don't know if this will work for cross-debugging, even if you do get
  23    a copy of the right include file.  */
  24 #include <machine/reg.h>
  25
  26 /* Define this if the C compiler puts an underscore at the front
  27    of external names before giving them to the linker.  */
  28
  29 #define NAMES_HAVE_UNDERSCORE
  30
  31 /* Offset from address of function to start of its code.
  32    Zero on most machines.  */
  33
  34 #define FUNCTION_START_OFFSET 0
  35
  36 /* Advance PC across any function entry prologue instructions
  37    to reach some "real" code.  */
  38
  39 #define SKIP_PROLOGUE(pc)                               \
  40 { register int op = read_memory_integer (pc, 1);        \
  41   if (op == 0x82)                                       \
  42     { op = read_memory_integer (pc+2,1);                \
  43       if ((op & 0x80) == 0) pc += 3;                    \
  44       else if ((op & 0xc0) == 0x80) pc += 4;            \
  45       else pc += 6;                                     \
  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 #define SAVED_PC_AFTER_CALL(frame) \
  54         read_memory_integer (read_register (SP_REGNUM), 4)
  55
  56 /* Address of end of stack space.  */
  57
  58 #define STACK_END_ADDR (0x800000)
  59
  60 /* Stack grows downward.  */
  61
  62 #define INNER_THAN <
  63
  64 /* Sequence of bytes for breakpoint instruction.  */
  65
  66 #define BREAKPOINT {0xf2}
  67
  68 /* Amount PC must be decremented by after a breakpoint.
  69    This is often the number of bytes in BREAKPOINT
  70    but not always.  */
  71
  72 #define DECR_PC_AFTER_BREAK 0
  73
  74 /* Nonzero if instruction at PC is a return instruction.  */
  75
  76 #define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 1) == 0x12)
  77
  78 /* Return 1 if P points to an invalid floating point value.  */
  79
  80 #define INVALID_FLOAT(p, len) 0
  81
  82 /* Define this to say that the "svc" insn is followed by
  83    codes in memory saying which kind of system call it is.  */
  84
  85 #define NS32K_SVC_IMMED_OPERANDS
  86
  87 /* Say how long (ordinary) registers are.  */
  88
  89 #define REGISTER_TYPE long
  90
  91 /* Number of machine registers */
  92
  93 #define NUM_REGS                25
  94
  95 #define NUM_GENERAL_REGS        8
  96
  97 /* Initializer for an array of names of registers.
  98    There should be NUM_REGS strings in this initializer.  */
  99
 100 #define REGISTER_NAMES {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
 101                         "pc", "sp", "fp", "ps",                         \
 102                         "fsr",                                          \
 103                         "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \
 104                         "l0", "l1", "l2", "l3", "l4",                   \
 105                         }
 106
 107 /* Register numbers of various important registers.
 108    Note that some of these values are "real" register numbers,
 109    and correspond to the general registers of the machine,
 110    and some are "phony" register numbers which are too large
 111    to be actual register numbers as far as the user is concerned
 112    but do serve to get the desired values when passed to read_register.  */
 113
 114 #define AP_REGNUM FP_REGNUM
 115 #define FP_REGNUM 10            /* Contains address of executing stack frame */
 116 #define SP_REGNUM 9             /* Contains address of top of stack */
 117 #define PC_REGNUM 8             /* Contains program counter */
 118 #define PS_REGNUM 11            /* Contains processor status */
 119 #define FPS_REGNUM 12           /* Floating point status register */
 120 #define FP0_REGNUM 13           /* Floating point register 0 */
 121 #define LP0_REGNUM 21           /* Double register 0 (same as FP0) */
 122
 123 /* Total amount of space needed to store our copies of the machine's
 124    register state, the array `registers'.  */
 125 #define REGISTER_BYTES ((NUM_REGS - 4) * sizeof (int) + 4 * sizeof (double))
 126
 127 /* Index within `registers' of the first byte of the space for
 128    register N.  */
 129
 130 #define REGISTER_BYTE(N) ((N) >= LP0_REGNUM ? \
 131         LP0_REGNUM * 4 + ((N) - LP0_REGNUM) * 8 : (N) * 4)
 132
 133 /* Number of bytes of storage in the actual machine representation
 134    for register N.  On the 32000, all regs are 4 bytes
 135    except for the doubled floating registers. */
 136
 137 #define REGISTER_RAW_SIZE(N) ((N) >= LP0_REGNUM ? 8 : 4)
 138
 139 /* Number of bytes of storage in the program's representation
 140    for register N.  On the 32000, all regs are 4 bytes
 141    except for the doubled floating registers. */
 142
 143 #define REGISTER_VIRTUAL_SIZE(N) ((N) >= LP0_REGNUM ? 8 : 4)
 144
 145 /* Largest value REGISTER_RAW_SIZE can have.  */
 146
 147 #define MAX_REGISTER_RAW_SIZE 8
 148
 149 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 150
 151 #define MAX_REGISTER_VIRTUAL_SIZE 8
 152
 153 /* Nonzero if register N requires conversion
 154    from raw format to virtual format.  */
 155
 156 #define REGISTER_CONVERTIBLE(N) 0
 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   bcopy ((FROM), (TO), REGISTER_VIRTUAL_SIZE(REGNUM));
 163
 164 /* Convert data from virtual format for register REGNUM
 165    to raw format for register REGNUM.  */
 166
 167 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
 168   bcopy ((FROM), (TO), REGISTER_VIRTUAL_SIZE(REGNUM));
 169
 170 /* Return the GDB type object for the "standard" data type
 171    of data in register N.  */
 172
 173 #define REGISTER_VIRTUAL_TYPE(N) \
 174   ((N) >= FP0_REGNUM ?          \
 175     ((N) >= LP0_REGNUM ?        \
 176      builtin_type_double        \
 177      : builtin_type_float)      \
 178    : builtin_type_int)
 179
 180 /* Store the address of the place in which to copy the structure the
 181    subroutine will return.  This is called from call_function.
 182
 183    On this machine this is a no-op, as gcc doesn't run on it yet.
 184    This calling convention is not used. */
 185
 186 #define STORE_STRUCT_RETURN(ADDR, SP)
 187
 188 /* Extract from an array REGBUF containing the (raw) register state
 189    a function return value of type TYPE, and copy that, in virtual format,
 190    into VALBUF.  */
 191
 192 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 193   bcopy (REGBUF, VALBUF, TYPE_LENGTH (TYPE))
 194
 195 /* Write into appropriate registers a function return value
 196    of type TYPE, given in virtual format.  */
 197
 198 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 199   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 200
 201 /* Extract from an array REGBUF containing the (raw) register state
 202    the address in which a function should return its structure value,
 203    as a CORE_ADDR (or an expression that can be used as one).  */
 204
 205 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 206 \f
 207 /* Describe the pointer in each stack frame to the previous stack frame
 208    (its caller).  */
 209
 210 /* FRAME_CHAIN takes a frame's nominal address
 211    and produces the frame's chain-pointer.
 212
 213    FRAME_CHAIN_COMBINE takes the chain pointer and the frame's nominal address
 214    and produces the nominal address of the caller frame.
 215
 216    However, if FRAME_CHAIN_VALID returns zero,
 217    it means the given frame is the outermost one and has no caller.
 218    In that case, FRAME_CHAIN_COMBINE is not used.  */
 219
 220 /* In the case of the Merlin, the frame's nominal address is the FP value,
 221    and at that address is saved previous FP value as a 4-byte word.  */
 222
 223 #define FRAME_CHAIN(thisframe)  \
 224   (outside_startup_file ((thisframe)->pc) ? \
 225    read_memory_integer ((thisframe)->frame, 4) :\
 226    0)
 227
 228 #define FRAME_CHAIN_VALID(chain, thisframe) \
 229   (chain != 0 && (outside_startup_file (FRAME_SAVED_PC (thisframe))))
 230
 231 #define FRAME_CHAIN_COMBINE(chain, thisframe) (chain)
 232
 233 /* Define other aspects of the stack frame.  */
 234
 235 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 4, 4))
 236
 237 /* compute base of arguments */
 238 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 239
 240 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 241
 242 /* Return number of args passed to a frame.
 243    Can return -1, meaning no way to tell.  */
 244
 245 #define FRAME_NUM_ARGS(numargs, fi)                     \
 246 { CORE_ADDR pc;                                         \
 247   int insn;                                             \
 248   int addr_mode;                                        \
 249   int width;                                            \
 250                                                         \
 251   pc = FRAME_SAVED_PC (fi);                             \
 252   insn = read_memory_integer (pc,2);                    \
 253   addr_mode = (insn >> 11) & 0x1f;                      \
 254   insn = insn & 0x7ff;                                  \
 255   if ((insn & 0x7fc) == 0x57c                           \
 256       && addr_mode == 0x14) /* immediate */             \
 257     { if (insn == 0x57c) /* adjspb */                   \
 258         width = 1;                                      \
 259       else if (insn == 0x57d) /* adjspw */              \
 260         width = 2;                                      \
 261       else if (insn == 0x57f) /* adjspd */              \
 262         width = 4;                                      \
 263       numargs = read_memory_integer (pc+2,width);       \
 264       if (width > 1)                                    \
 265         flip_bytes (&numargs, width);                   \
 266       numargs = - sign_extend (numargs, width*8) / 4; } \
 267   else numargs = -1;                                    \
 268 }
 269
 270 /* Return number of bytes at start of arglist that are not really args.  */
 271
 272 #define FRAME_ARGS_SKIP 8
 273
 274 /* Put here the code to store, into a struct frame_saved_regs,
 275    the addresses of the saved registers of frame described by FRAME_INFO.
 276    This includes special registers such as pc and fp saved in special
 277    ways in the stack frame.  sp is even more special:
 278    the address we return for it IS the sp for the next frame.  */
 279
 280 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 281 { int regmask,regnum;                                           \
 282   int localcount;                                               \
 283   CORE_ADDR enter_addr;                                         \
 284   CORE_ADDR next_addr;                                          \
 285                                                                 \
 286   enter_addr = get_pc_function_start ((frame_info)->pc);        \
 287   regmask = read_memory_integer (enter_addr+1, 1);              \
 288   localcount = ns32k_localcount (enter_addr);                   \
 289   next_addr = (frame_info)->frame + localcount;                 \
 290   for (regnum = 0; regnum < 8; regnum++, regmask >>= 1)         \
 291     (frame_saved_regs).regs[regnum]                             \
 292       = (regmask & 1) ? (next_addr -= 4) : 0;                   \
 293   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 4; \
 294   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4; \
 295   (frame_saved_regs).regs[FP_REGNUM]                            \
 296      = read_memory_integer ((frame_info)->frame, 4); }
 297
 298 \f
 299 /* Things needed for making the inferior call functions.  */
 300
 301 /* Push an empty stack frame, to record the current PC, etc.  */
 302
 303 #define PUSH_DUMMY_FRAME \
 304 { register CORE_ADDR sp = read_register (SP_REGNUM);    \
 305   register int regnum;                                  \
 306   sp = push_word (sp, read_register (PC_REGNUM));       \
 307   sp = push_word (sp, read_register (FP_REGNUM));       \
 308   write_register (FP_REGNUM, sp);                       \
 309   for (regnum = 0; regnum < 8; regnum++)                \
 310     sp = push_word (sp, read_register (regnum));        \
 311   write_register (SP_REGNUM, sp);                       \
 312 }
 313
 314 /* Discard from the stack the innermost frame, restoring all registers.  */
 315
 316 #define POP_FRAME  \
 317 { register FRAME frame = get_current_frame ();                   \
 318   register CORE_ADDR fp;                                         \
 319   register int regnum;                                           \
 320   struct frame_saved_regs fsr;                                   \
 321   struct frame_info *fi;                                                 \
 322   fi = get_frame_info (frame);                                   \
 323   fp = fi->frame;                                                \
 324   get_frame_saved_regs (fi, &fsr);                               \
 325   for (regnum = 0; regnum < 8; regnum++)                         \
 326     if (fsr.regs[regnum])                                        \
 327       write_register (regnum, read_memory_integer (fsr.regs[regnum], 4)); \
 328   write_register (FP_REGNUM, read_memory_integer (fp, 4));       \
 329   write_register (PC_REGNUM, read_memory_integer (fp + 4, 4));   \
 330   write_register (SP_REGNUM, fp + 8);                            \
 331   flush_cached_frames ();                                        \
 332   set_current_frame (create_new_frame (read_register (FP_REGNUM),\
 333                                        read_pc ()));             \
 334 }
 335
 336 /* This sequence of words is the instructions
 337      enter      0xff,0          82 ff 00
 338      jsr        @0x00010203     7f ae c0 01 02 03
 339      adjspd     0x69696969      7f a5 01 02 03 04
 340      bpt                        f2
 341    Note this is 16 bytes.  */
 342
 343 #define CALL_DUMMY { 0x7f00ff82, 0x0201c0ae, 0x01a57f03, 0xf2040302 }
 344
 345 #define CALL_DUMMY_START_OFFSET 3
 346 #define CALL_DUMMY_LENGTH       16
 347 #define CALL_DUMMY_ADDR         5
 348 #define CALL_DUMMY_NARGS        11
 349
 350 /* Insert the specified number of args and function address
 351    into a call sequence of the above form stored at DUMMYNAME.  */
 352
 353 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)            \
 354 { int flipped = fun | 0xc0000000;                               \
 355   flip_bytes (&flipped, 4);                                     \
 356   *((int *) (((char *) dummyname)+CALL_DUMMY_ADDR)) = flipped;  \
 357   flipped = - nargs * 4;                                        \
 358   flip_bytes (&flipped, 4);                                     \
 359   *((int *) (((char *) dummyname)+CALL_DUMMY_NARGS)) = flipped; \
 360 }