gdb/tm-tahoe.h

   1 /* Definitions to make GDB target for a tahoe running 4.3-Reno.
   2    Copyright (C) 1986, 1987, 1989, 1991 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 GDB 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 1, or (at your option)
   9 any later version.
  10
  11 GDB 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 GDB; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 /*
  21  * Ported by the State University of New York at Buffalo by the Distributed
  22  * Computer Systems Lab, Department of Computer Science, 1991.
  23  */
  24
  25 #define TARGET_BYTE_ORDER BIG_ENDIAN
  26 #define BITS_BIG_ENDIAN 0
  27
  28 /* Define this if the C compiler puts an underscore at the front
  29    of external names before giving them to the linker.  */
  30
  31 #define NAMES_HAVE_UNDERSCORE
  32
  33 /* Debugger information will be in DBX format.  */
  34
  35 #define READ_DBX_FORMAT
  36
  37 /* Offset from address of function to start of its code.
  38    Zero on most machines.  */
  39
  40 #define FUNCTION_START_OFFSET 2
  41
  42 /* Advance PC across any function entry prologue instructions
  43    to reach some "real" code.  */
  44
  45 #define SKIP_PROLOGUE(pc)       \
  46 { register int op = (unsigned char) read_memory_integer (pc, 1);  \
  47   if (op == 0x11) pc += 2;  /* skip brb */                        \
  48   if (op == 0x13) pc += 3;  /* skip brw */                        \
  49   if (op == 0x2c &&                                               \
  50       ((unsigned char) read_memory_integer (pc+2, 1)) == 0x5e)    \
  51     pc += 3;  /* skip subl2 */                                    \
  52   if (op == 0xe9 &&                                               \
  53       ((unsigned char) read_memory_integer (pc+1, 1)) == 0xae &&  \
  54       ((unsigned char) read_memory_integer(pc+3, 1)) == 0x5e)     \
  55      pc += 4;  /* skip movab */                                   \
  56   if (op == 0xe9 &&                                               \
  57       ((unsigned char) read_memory_integer (pc+1, 1)) == 0xce &&  \
  58       ((unsigned char) read_memory_integer(pc+4, 1)) == 0x5e)     \
  59     pc += 5;  /* skip movab */                                    \
  60   if (op == 0xe9 &&                                               \
  61       ((unsigned char) read_memory_integer (pc+1, 1)) == 0xee &&  \
  62       ((unsigned char) read_memory_integer(pc+6, 1)) == 0x5e)     \
  63     pc += 7;  /* skip movab */                                    \
  64 }
  65
  66 /* Immediately after a function call, return the saved pc.
  67    Can't always go through the frames for this because on some machines
  68    the new frame is not set up until the new function executes
  69    some instructions.  */
  70
  71 #define SAVED_PC_AFTER_CALL(frame) FRAME_SAVED_PC(frame)
  72
  73 /* Wrong for cross-debugging.  I don't know the real values.  */
  74 #define TARGET_UPAGES UPAGES
  75 #define TARGET_NBPG NBPG
  76
  77 /* This is the amount to subtract from u.u_ar0
  78    to get the offset in the core file of the register values.  */
  79
  80 #define KERNEL_U_ADDR (0xc0000000 - (TARGET_UPAGES * TARGET_NBPG))
  81
  82 /* Address of end of stack space.  */
  83
  84 #define STACK_END_ADDR (0xc0000000 - (TARGET_UPAGES * TARGET_NBPG))
  85
  86 /* On BSD, sigtramp is in the u area.  Can't check the exact
  87    addresses because for cross-debugging we don't have target include
  88    files around.  This should be close enough.  */
  89 #define IN_SIGTRAMP(pc, name) ((pc) >= STACK_END_ADDR && (pc < 0xc0000000))
  90
  91 /* Stack grows downward.  */
  92
  93 #define INNER_THAN <
  94
  95 /* Sequence of bytes for breakpoint instruction.  */
  96
  97 #define BREAKPOINT {0x30}
  98
  99 /* Amount PC must be decremented by after a breakpoint.
 100    This is often the number of bytes in BREAKPOINT
 101    but not always.  */
 102
 103 #define DECR_PC_AFTER_BREAK 0
 104
 105 /* Nonzero if instruction at PC is a return instruction.  */
 106
 107 #define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 1) == 0x40)
 108
 109 /* Return 1 if P points to an invalid floating point value.
 110    LEN is the length in bytes -- not relevant on the Tahoe. */
 111
 112 #define INVALID_FLOAT(p, len) ((*(short *) p & 0xff80) == 0x8000)
 113
 114 /* Say how long (ordinary) registers are.  */
 115
 116 #define REGISTER_TYPE long
 117
 118 /* Number of machine registers */
 119
 120 #define NUM_REGS 19
 121
 122 /* Initializer for an array of names of registers.
 123    There should be NUM_REGS strings in this initializer.  */
 124
 125 #define REGISTER_NAMES {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "fp", "sp", "pc", "ps", "al", "ah"}
 126
 127 #define FP_REGNUM 13            /* Contains address of executing stack frame */
 128 #define SP_REGNUM 14            /* Contains address of top of stack */
 129 #define PC_REGNUM 15            /* Contains program counter */
 130 #define PS_REGNUM 16            /* Contains processor status */
 131
 132 #define AL_REGNUM 17            /* Contains accumulator */
 133 #define AH_REGNUM 18
 134
 135 /* Total amount of space needed to store our copies of the machine's
 136    register state, the array `registers'.  */
 137
 138 #define REGISTER_BYTES (19*4)
 139
 140 /* Index within `registers' of the first byte of the space for
 141    register N.  */
 142
 143 #define REGISTER_BYTE(N) ((N) * 4)
 144
 145 /* Number of bytes of storage in the actual machine representation
 146    for register N.  On the tahoe, all regs are 4 bytes.  */
 147
 148 #define REGISTER_RAW_SIZE(N) 4
 149
 150 /* Number of bytes of storage in the program's representation
 151    for register N.  On the tahoe, all regs are 4 bytes.  */
 152
 153 #define REGISTER_VIRTUAL_SIZE(N) 4
 154
 155 /* Largest value REGISTER_RAW_SIZE can have.  */
 156
 157 #define MAX_REGISTER_RAW_SIZE 4
 158
 159 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 160
 161 #define MAX_REGISTER_VIRTUAL_SIZE 4
 162
 163 /* Nonzero if register N requires conversion
 164    from raw format to virtual format.  */
 165
 166 #define REGISTER_CONVERTIBLE(N) 0
 167
 168 /* Convert data from raw format for register REGNUM
 169    to virtual format for register REGNUM.  */
 170
 171 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO)     \
 172   bcopy ((FROM), (TO), 4);
 173
 174 /* Convert data from virtual format for register REGNUM
 175    to raw format for register REGNUM.  */
 176
 177 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
 178   bcopy ((FROM), (TO), 4);
 179
 180 /* Return the GDB type object for the "standard" data type
 181    of data in register N.  */
 182
 183 #define REGISTER_VIRTUAL_TYPE(N) builtin_type_int
 184
 185 /* Store the address of the place in which to copy the structure the
 186    subroutine will return.  This is called from call_function. */
 187
 188 #define STORE_STRUCT_RETURN(ADDR, SP) \
 189   { write_register (1, (ADDR)); }
 190
 191 /* Extract from an array REGBUF containing the (raw) register state
 192    a function return value of type TYPE, and copy that, in virtual format,
 193    into VALBUF.  */
 194
 195 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 196   bcopy (REGBUF, VALBUF, TYPE_LENGTH (TYPE))
 197
 198 /* Write into appropriate registers a function return value
 199    of type TYPE, given in virtual format.  */
 200
 201 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 202   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 203
 204 /* Extract from an array REGBUF containing the (raw) register state
 205    the address in which a function should return its structure value,
 206    as a CORE_ADDR (or an expression that can be used as one).  */
 207
 208 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 209
 210 /* Describe the pointer in each stack frame to the previous stack frame
 211    (its caller).
 212
 213    FRAME_CHAIN takes a frame's nominal address
 214    and produces the frame's chain-pointer.
 215
 216    FRAME_CHAIN_COMBINE takes the chain pointer and the frame's nominal address
 217    and produces the nominal address of the caller frame.
 218
 219    However, if FRAME_CHAIN_VALID returns zero,
 220    it means the given frame is the outermost one and has no caller.
 221    In that case, FRAME_CHAIN_COMBINE is not used.  */
 222
 223 /* In the case of the Tahoe, the frame's nominal address is the FP value,
 224    and it points to the old FP */
 225
 226 #define FRAME_CHAIN(thisframe)  \
 227   (outside_startup_file ((thisframe)->pc) ? \
 228    read_memory_integer ((thisframe)->frame, 4) :\
 229    0)
 230
 231 #define FRAME_CHAIN_VALID(chain, thisframe) \
 232   (chain != 0 && (outside_startup_file (FRAME_SAVED_PC (thisframe))))
 233
 234 #define FRAME_CHAIN_COMBINE(chain, thisframe) (chain)
 235
 236 /* Define other aspects of the stack frame.  */
 237
 238 /* Saved PC */
 239
 240 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame - 8, 4))
 241
 242 /* In most of GDB, getting the args address is too important to
 243    just say "I don't know". */
 244
 245 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame+4)
 246
 247 /* Address to use as an anchor for finding local variables */
 248
 249 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 250
 251 /* Return number of args passed to a frame.
 252    Can return -1, meaning no way to tell.  */
 253
 254 #define FRAME_NUM_ARGS(numargs, fi)  \
 255 { numargs = ((0xffff & read_memory_integer(((fi)->frame-4),4)) - 4) >> 2; }
 256
 257 /* Return number of bytes at start of arglist that are not really args.  */
 258
 259 #define FRAME_ARGS_SKIP 0
 260
 261 /* Put here the code to store, into a struct frame_saved_regs,
 262    the addresses of the saved registers of frame described by FRAME_INFO.
 263    This includes special registers such as pc and fp saved in special
 264    ways in the stack frame.  sp is even more special:
 265    the address we return for it IS the sp for the next frame.  */
 266
 267 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 268 { register int regnum;     \
 269   register int rmask = read_memory_integer ((frame_info)->frame-4, 4) >> 16;\
 270   register CORE_ADDR next_addr;     \
 271   bzero (&frame_saved_regs, sizeof frame_saved_regs);     \
 272   next_addr = (frame_info)->frame - 8;     \
 273   for (regnum = 12; regnum >= 0; regnum--, rmask <<= 1)  \
 274     (frame_saved_regs).regs[regnum] = (rmask & 0x1000) ? (next_addr -= 4) : 0;\
 275   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 4;  \
 276   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame - 8;  \
 277   (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame;      \
 278 }
 279
 280 /* Things needed for making the inferior call functions.  */
 281
 282 /* Push an empty stack frame, to record the current PC, etc.  */
 283
 284 #define PUSH_DUMMY_FRAME \
 285 { register CORE_ADDR sp = read_register (SP_REGNUM);    \
 286   register int regnum;                                  \
 287 printf("PUSH_DUMMY_FRAME\n");                           \
 288   sp = push_word (sp, read_register (FP_REGNUM));       \
 289   write_register (FP_REGNUM, sp);                       \
 290   sp = push_word (sp, 0x1fff0004);   /*SAVE MASK*/      \
 291   sp = push_word (sp, read_register (PC_REGNUM));       \
 292   for (regnum = 12; regnum >= 0; regnum--)              \
 293     sp = push_word (sp, read_register (regnum));        \
 294   write_register (SP_REGNUM, sp);                       \
 295 }
 296
 297 /* Discard from the stack the innermost frame, restoring all registers.  */
 298
 299 #define POP_FRAME  \
 300 { register CORE_ADDR fp = read_register (FP_REGNUM);                    \
 301   register int regnum;                                                  \
 302   register int regmask = read_memory_integer (fp-4, 4);                 \
 303 printf("POP_FRAME\n");                                                  \
 304   regmask >>= 16;                                                       \
 305   write_register (SP_REGNUM, fp+4);                                     \
 306   write_register (PC_REGNUM, read_memory_integer(fp-8, 4));             \
 307   write_register (FP_REGNUM, read_memory_integer(fp, 4));               \
 308   fp -= 8;                                                              \
 309   for (regnum = 12; regnum >= 0; regnum--, regmask <<= 1)               \
 310     if (regmask & 0x1000)                                               \
 311       write_register (regnum, read_memory_integer (fp-=4, 4));          \
 312   flush_cached_frames ();                                               \
 313   set_current_frame (create_new_frame (read_register (FP_REGNUM),       \
 314                                         read_pc ())); }
 315
 316 /* This sequence of words is the instructions
 317      calls #69, @#32323232
 318      bpt
 319    Note this is 8 bytes.  */
 320
 321 #define CALL_DUMMY {0xbf699f32, 0x32323230}
 322
 323 /* Start execution at beginning of dummy */
 324
 325 #define CALL_DUMMY_START_OFFSET 0
 326
 327 /* Insert the specified number of args and function address
 328    into a call sequence of the above form stored at DUMMYNAME.  */
 329
 330 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, type)   \
 331 { int temp = (int) fun;                         \
 332   *((char *) dummyname + 1) = nargs;            \
 333   bcopy(&temp,(char *)dummyname+3,4); }
 334