gdb/tm-i386v.h

   1 /* Macro defintions for i386.
   2    Copyright (C) 1986, 1987, 1989 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  * Changes for 80386 by Pace Willisson (pace@prep.ai.mit.edu)
  22  * July 1988
  23  */
  24
  25 #define TARGET_BYTE_ORDER LITTLE_ENDIAN
  26
  27 /* define this if you don't have the extension to coff that allows
  28  * file names to appear in the string table
  29  * (aux.x_file.x_foff)
  30  */
  31 #define COFF_NO_LONG_FILE_NAMES
  32
  33 /* turn this on when rest of gdb is ready */
  34 /* #define IEEE_FLOAT */
  35
  36 /* Define this if the C compiler puts an underscore at the front
  37    of external names before giving them to the linker.  */
  38
  39 /* #define NAMES_HAVE_UNDERSCORE */
  40
  41 /* Specify debugger information format.  */
  42
  43 /* #define READ_DBX_FORMAT */
  44 #define COFF_FORMAT
  45
  46 /* number of traps that happen between exec'ing the shell
  47  * to run an inferior, and when we finally get to
  48  * the inferior code.  This is 2 on most implementations.
  49  */
  50 #define START_INFERIOR_TRAPS_EXPECTED 4
  51
  52 /* Offset from address of function to start of its code.
  53    Zero on most machines.  */
  54
  55 #define FUNCTION_START_OFFSET 0
  56
  57 /* Advance PC across any function entry prologue instructions
  58    to reach some "real" code.  */
  59
  60 #define SKIP_PROLOGUE(frompc)   {(frompc) = i386_skip_prologue((frompc));}
  61
  62 /* Immediately after a function call, return the saved pc.
  63    Can't always go through the frames for this because on some machines
  64    the new frame is not set up until the new function executes
  65    some instructions.  */
  66
  67 #define SAVED_PC_AFTER_CALL(frame) \
  68   (read_memory_integer (read_register (SP_REGNUM), 4))
  69
  70 /* This is only supposed to work in execcore.c, where x == 0 and
  71    this is called before any other fields are filled in.  */
  72 #define N_SET_MAGIC(aouthdr, x) \
  73   bzero ((char *) &aouthdr, sizeof aouthdr)
  74
  75 /* Address of end of stack space.  */
  76
  77 #define STACK_END_ADDR 0x80000000
  78
  79 /* Stack grows downward.  */
  80
  81 #define INNER_THAN <
  82
  83 /* Sequence of bytes for breakpoint instruction.  */
  84
  85 #define BREAKPOINT {0xcc}
  86
  87 /* Amount PC must be decremented by after a breakpoint.
  88    This is often the number of bytes in BREAKPOINT
  89    but not always.  */
  90
  91 #define DECR_PC_AFTER_BREAK 1
  92
  93 /* Nonzero if instruction at PC is a return instruction.  */
  94
  95 #define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 1) == 0xc3)
  96
  97 /* Return 1 if P points to an invalid floating point value.
  98    LEN is the length in bytes -- not relevant on the 386.  */
  99
 100 #define INVALID_FLOAT(p, len) (0)
 101
 102 #if 0
 103 /* code to execute to print interesting information about the
 104    floating point processor (if any)
 105    No need to define if there is nothing to do.
 106    On the 386, unfortunately this code is host-dependent (and lives
 107    in the i386-xdep.c file), so we can't
 108    do this unless we *know* we aren't cross-debugging.  FIXME.
 109  */
 110 #define FLOAT_INFO { i386_float_info (); }
 111 #endif 0
 112
 113 /* Say how long (ordinary) registers are.  */
 114
 115 #define REGISTER_TYPE long
 116
 117 /* Number of machine registers */
 118
 119 #define NUM_REGS 16
 120
 121 /* Initializer for an array of names of registers.
 122    There should be NUM_REGS strings in this initializer.  */
 123
 124 /* the order of the first 8 registers must match the compiler's
 125  * numbering scheme (which is the same as the 386 scheme)
 126  * also, this table must match regmap in i386-pinsn.c.
 127  */
 128 #define REGISTER_NAMES { "eax", "ecx", "edx", "ebx", \
 129                          "esp", "ebp", "esi", "edi", \
 130                          "eip", "ps", "cs", "ss", \
 131                          "ds", "es", "fs", "gs", \
 132                          }
 133
 134 /* Register numbers of various important registers.
 135    Note that some of these values are "real" register numbers,
 136    and correspond to the general registers of the machine,
 137    and some are "phony" register numbers which are too large
 138    to be actual register numbers as far as the user is concerned
 139    but do serve to get the desired values when passed to read_register.  */
 140
 141 #define FP_REGNUM 5             /* Contains address of executing stack frame */
 142 #define SP_REGNUM 4             /* Contains address of top of stack */
 143
 144 #define PC_REGNUM 8
 145 #define PS_REGNUM 9
 146
 147 #define REGISTER_U_ADDR(addr, blockend, regno) \
 148         (addr) = i386_register_u_addr ((blockend),(regno));
 149
 150 /* Total amount of space needed to store our copies of the machine's
 151    register state, the array `registers'.  */
 152 #define REGISTER_BYTES (NUM_REGS * 4)
 153
 154 /* Index within `registers' of the first byte of the space for
 155    register N.  */
 156
 157 #define REGISTER_BYTE(N) ((N)*4)
 158
 159 /* Number of bytes of storage in the actual machine representation
 160    for register N.  */
 161
 162 #define REGISTER_RAW_SIZE(N) (4)
 163
 164 /* Number of bytes of storage in the program's representation
 165    for register N. */
 166
 167 #define REGISTER_VIRTUAL_SIZE(N) (4)
 168
 169 /* Largest value REGISTER_RAW_SIZE can have.  */
 170
 171 #define MAX_REGISTER_RAW_SIZE 4
 172
 173 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 174
 175 #define MAX_REGISTER_VIRTUAL_SIZE 4
 176
 177 /* Nonzero if register N requires conversion
 178    from raw format to virtual format.  */
 179
 180 #define REGISTER_CONVERTIBLE(N) (0)
 181
 182 /* Convert data from raw format for register REGNUM
 183    to virtual format for register REGNUM.  */
 184
 185 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) {bcopy ((FROM), (TO), 4);}
 186
 187 /* Convert data from virtual format for register REGNUM
 188    to raw format for register REGNUM.  */
 189
 190 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) {bcopy ((FROM), (TO), 4);}
 191
 192 /* Return the GDB type object for the "standard" data type
 193    of data in register N.  */
 194
 195 #define REGISTER_VIRTUAL_TYPE(N) (builtin_type_int)
 196
 197 /* Store the address of the place in which to copy the structure the
 198    subroutine will return.  This is called from call_function. */
 199
 200 #define STORE_STRUCT_RETURN(ADDR, SP) \
 201   { (SP) -= sizeof (ADDR);              \
 202     write_memory ((SP), &(ADDR), sizeof (ADDR)); }
 203
 204 /* Extract from an array REGBUF containing the (raw) register state
 205    a function return value of type TYPE, and copy that, in virtual format,
 206    into VALBUF.  */
 207
 208 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 209   bcopy (REGBUF, VALBUF, TYPE_LENGTH (TYPE))
 210
 211 /* Write into appropriate registers a function return value
 212    of type TYPE, given in virtual format.  */
 213
 214 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 215   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 216
 217 /* Extract from an array REGBUF containing the (raw) register state
 218    the address in which a function should return its structure value,
 219    as a CORE_ADDR (or an expression that can be used as one).  */
 220
 221 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 222
 223 \f
 224 /* Describe the pointer in each stack frame to the previous stack frame
 225    (its caller).  */
 226
 227 /* FRAME_CHAIN takes a frame's nominal address
 228    and produces the frame's chain-pointer.
 229
 230    FRAME_CHAIN_COMBINE takes the chain pointer and the frame's nominal address
 231    and produces the nominal address of the caller frame.
 232
 233    However, if FRAME_CHAIN_VALID returns zero,
 234    it means the given frame is the outermost one and has no caller.
 235    In that case, FRAME_CHAIN_COMBINE is not used.  */
 236
 237 #define FRAME_CHAIN(thisframe) \
 238   (outside_startup_file ((thisframe)->pc) ? \
 239    read_memory_integer ((thisframe)->frame, 4) :\
 240    0)
 241
 242 #define FRAME_CHAIN_VALID(chain, thisframe) \
 243   (chain != 0 && (outside_startup_file (FRAME_SAVED_PC (thisframe))))
 244
 245 #define FRAME_CHAIN_COMBINE(chain, thisframe) (chain)
 246
 247 /* Define other aspects of the stack frame.  */
 248
 249 /* A macro that tells us whether the function invocation represented
 250    by FI does not have a frame on the stack associated with it.  If it
 251    does not, FRAMELESS is set to 1, else 0.  */
 252 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 253   (FRAMELESS) = frameless_look_for_prologue(FI)
 254
 255 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 4, 4))
 256
 257 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 258
 259 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 260
 261 /* Return number of args passed to a frame.
 262    Can return -1, meaning no way to tell.  */
 263
 264 #define FRAME_NUM_ARGS(numargs, fi) (numargs) = i386_frame_num_args(fi)
 265
 266 /* Return number of bytes at start of arglist that are not really args.  */
 267
 268 #define FRAME_ARGS_SKIP 8
 269
 270 /* Put here the code to store, into a struct frame_saved_regs,
 271    the addresses of the saved registers of frame described by FRAME_INFO.
 272    This includes special registers such as pc and fp saved in special
 273    ways in the stack frame.  sp is even more special:
 274    the address we return for it IS the sp for the next frame.  */
 275
 276 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 277 { i386_frame_find_saved_regs ((frame_info), &(frame_saved_regs)); }
 278
 279 \f
 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 { i386_push_dummy_frame (); }
 285
 286 /* Discard from the stack the innermost frame, restoring all registers.  */
 287
 288 #define POP_FRAME  { i386_pop_frame (); }
 289
 290 /* this is
 291  *   call 11223344 (32 bit relative)
 292  *   int3
 293  */
 294
 295 #define CALL_DUMMY { 0x223344e8, 0xcc11 }
 296
 297 #define CALL_DUMMY_LENGTH 8
 298
 299 #define CALL_DUMMY_START_OFFSET 0  /* Start execution at beginning of dummy */
 300
 301 /* Insert the specified number of args and function address
 302    into a call sequence of the above form stored at DUMMYNAME.  */
 303
 304 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)   \
 305 { \
 306         int from, to, delta, loc; \
 307         loc = (int)(read_register (SP_REGNUM) - CALL_DUMMY_LENGTH); \
 308         from = loc + 5; \
 309         to = (int)(fun); \
 310         delta = to - from; \
 311         *(int *)((char *)(dummyname) + 1) = delta; \
 312 }