gdb/tm-i386v.h

   1 /* Macro defintions for i386.
   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 /*
  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 /* number of traps that happen between exec'ing the shell
  42  * to run an inferior, and when we finally get to
  43  * the inferior code.  This is 2 on most implementations.
  44  */
  45 #define START_INFERIOR_TRAPS_EXPECTED 4
  46
  47 /* Offset from address of function to start of its code.
  48    Zero on most machines.  */
  49
  50 #define FUNCTION_START_OFFSET 0
  51
  52 /* Advance PC across any function entry prologue instructions
  53    to reach some "real" code.  */
  54
  55 #define SKIP_PROLOGUE(frompc)   {(frompc) = i386_skip_prologue((frompc));}
  56
  57 /* Immediately after a function call, return the saved pc.
  58    Can't always go through the frames for this because on some machines
  59    the new frame is not set up until the new function executes
  60    some instructions.  */
  61
  62 #define SAVED_PC_AFTER_CALL(frame) \
  63   (read_memory_integer (read_register (SP_REGNUM), 4))
  64
  65 /* Address of end of stack space.  */
  66
  67 #define STACK_END_ADDR 0x80000000
  68
  69 /* Stack grows downward.  */
  70
  71 #define INNER_THAN <
  72
  73 /* Sequence of bytes for breakpoint instruction.  */
  74
  75 #define BREAKPOINT {0xcc}
  76
  77 /* Amount PC must be decremented by after a breakpoint.
  78    This is often the number of bytes in BREAKPOINT
  79    but not always.  */
  80
  81 #define DECR_PC_AFTER_BREAK 1
  82
  83 /* Nonzero if instruction at PC is a return instruction.  */
  84
  85 #define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 1) == 0xc3)
  86
  87 /* Return 1 if P points to an invalid floating point value.
  88    LEN is the length in bytes -- not relevant on the 386.  */
  89
  90 #define INVALID_FLOAT(p, len) (0)
  91
  92 #if 0
  93 /* code to execute to print interesting information about the
  94    floating point processor (if any)
  95    No need to define if there is nothing to do.
  96    On the 386, unfortunately this code is host-dependent (and lives
  97    in the i386-xdep.c file), so we can't
  98    do this unless we *know* we aren't cross-debugging.  FIXME.
  99  */
 100 #define FLOAT_INFO { i386_float_info (); }
 101 #endif /*0*/
 102
 103 /* Say how long (ordinary) registers are.  */
 104
 105 #define REGISTER_TYPE long
 106
 107 /* Number of machine registers */
 108
 109 #define NUM_REGS 16
 110
 111 /* Initializer for an array of names of registers.
 112    There should be NUM_REGS strings in this initializer.  */
 113
 114 /* the order of the first 8 registers must match the compiler's
 115  * numbering scheme (which is the same as the 386 scheme)
 116  * also, this table must match regmap in i386-pinsn.c.
 117  */
 118 #define REGISTER_NAMES { "eax", "ecx", "edx", "ebx", \
 119                          "esp", "ebp", "esi", "edi", \
 120                          "eip", "ps", "cs", "ss", \
 121                          "ds", "es", "fs", "gs", \
 122                          }
 123
 124 /* Register numbers of various important registers.
 125    Note that some of these values are "real" register numbers,
 126    and correspond to the general registers of the machine,
 127    and some are "phony" register numbers which are too large
 128    to be actual register numbers as far as the user is concerned
 129    but do serve to get the desired values when passed to read_register.  */
 130
 131 #define FP_REGNUM 5             /* Contains address of executing stack frame */
 132 #define SP_REGNUM 4             /* Contains address of top of stack */
 133
 134 #define PC_REGNUM 8
 135 #define PS_REGNUM 9
 136
 137 /* Total amount of space needed to store our copies of the machine's
 138    register state, the array `registers'.  */
 139 #define REGISTER_BYTES (NUM_REGS * 4)
 140
 141 /* Index within `registers' of the first byte of the space for
 142    register N.  */
 143
 144 #define REGISTER_BYTE(N) ((N)*4)
 145
 146 /* Number of bytes of storage in the actual machine representation
 147    for register N.  */
 148
 149 #define REGISTER_RAW_SIZE(N) (4)
 150
 151 /* Number of bytes of storage in the program's representation
 152    for register N. */
 153
 154 #define REGISTER_VIRTUAL_SIZE(N) (4)
 155
 156 /* Largest value REGISTER_RAW_SIZE can have.  */
 157
 158 #define MAX_REGISTER_RAW_SIZE 4
 159
 160 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 161
 162 #define MAX_REGISTER_VIRTUAL_SIZE 4
 163
 164 /* Nonzero if register N requires conversion
 165    from raw format to virtual format.  */
 166
 167 #define REGISTER_CONVERTIBLE(N) (0)
 168
 169 /* Convert data from raw format for register REGNUM
 170    to virtual format for register REGNUM.  */
 171
 172 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) {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) {bcopy ((FROM), (TO), 4);}
 178
 179 /* Return the GDB type object for the "standard" data type
 180    of data in register N.  */
 181 /* Perhaps si and di should go here, but potentially they could be
 182    used for things other than address.  */
 183 #define REGISTER_VIRTUAL_TYPE(N) \
 184   ((N) == PC_REGNUM || (N) == FP_REGNUM || (N) == SP_REGNUM ?         \
 185    lookup_pointer_type (builtin_type_void) : builtin_type_int)
 186
 187 /* Store the address of the place in which to copy the structure the
 188    subroutine will return.  This is called from call_function. */
 189
 190 #define STORE_STRUCT_RETURN(ADDR, SP) \
 191   { (SP) -= sizeof (ADDR);              \
 192     write_memory ((SP), &(ADDR), sizeof (ADDR)); }
 193
 194 /* Extract from an array REGBUF containing the (raw) register state
 195    a function return value of type TYPE, and copy that, in virtual format,
 196    into VALBUF.  */
 197
 198 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 199   bcopy (REGBUF, VALBUF, TYPE_LENGTH (TYPE))
 200
 201 /* Write into appropriate registers a function return value
 202    of type TYPE, given in virtual format.  */
 203
 204 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 205   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 206
 207 /* Extract from an array REGBUF containing the (raw) register state
 208    the address in which a function should return its structure value,
 209    as a CORE_ADDR (or an expression that can be used as one).  */
 210
 211 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 212
 213 \f
 214 /* Describe the pointer in each stack frame to the previous stack frame
 215    (its caller).  */
 216
 217 /* FRAME_CHAIN takes a frame's nominal address
 218    and produces the frame's chain-pointer.
 219
 220    FRAME_CHAIN_COMBINE takes the chain pointer and the frame's nominal address
 221    and produces the nominal address of the caller frame.
 222
 223    However, if FRAME_CHAIN_VALID returns zero,
 224    it means the given frame is the outermost one and has no caller.
 225    In that case, FRAME_CHAIN_COMBINE is not used.  */
 226
 227 #define FRAME_CHAIN(thisframe) \
 228   (outside_startup_file ((thisframe)->pc) ? \
 229    read_memory_integer ((thisframe)->frame, 4) :\
 230    0)
 231
 232 #define FRAME_CHAIN_VALID(chain, thisframe) \
 233   (chain != 0 && (outside_startup_file (FRAME_SAVED_PC (thisframe))))
 234
 235 #define FRAME_CHAIN_COMBINE(chain, thisframe) (chain)
 236
 237 /* Define other aspects of the stack frame.  */
 238
 239 /* A macro that tells us whether the function invocation represented
 240    by FI does not have a frame on the stack associated with it.  If it
 241    does not, FRAMELESS is set to 1, else 0.  */
 242 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 243   (FRAMELESS) = frameless_look_for_prologue(FI)
 244
 245 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 4, 4))
 246
 247 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 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) (numargs) = i386_frame_num_args(fi)
 255
 256 /* Return number of bytes at start of arglist that are not really args.  */
 257
 258 #define FRAME_ARGS_SKIP 8
 259
 260 /* Put here the code to store, into a struct frame_saved_regs,
 261    the addresses of the saved registers of frame described by FRAME_INFO.
 262    This includes special registers such as pc and fp saved in special
 263    ways in the stack frame.  sp is even more special:
 264    the address we return for it IS the sp for the next frame.  */
 265
 266 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 267 { i386_frame_find_saved_regs ((frame_info), &(frame_saved_regs)); }
 268
 269 \f
 270 /* Things needed for making the inferior call functions.  */
 271
 272 /* Push an empty stack frame, to record the current PC, etc.  */
 273
 274 #define PUSH_DUMMY_FRAME { i386_push_dummy_frame (); }
 275
 276 /* Discard from the stack the innermost frame, restoring all registers.  */
 277
 278 #define POP_FRAME  { i386_pop_frame (); }
 279
 280 /* this is
 281  *   call 11223344 (32 bit relative)
 282  *   int3
 283  */
 284
 285 #define CALL_DUMMY { 0x223344e8, 0xcc11 }
 286
 287 #define CALL_DUMMY_LENGTH 8
 288
 289 #define CALL_DUMMY_START_OFFSET 0  /* Start execution at beginning of dummy */
 290
 291 /* Insert the specified number of args and function address
 292    into a call sequence of the above form stored at DUMMYNAME.  */
 293
 294 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)   \
 295 { \
 296         int from, to, delta, loc; \
 297         loc = (int)(read_register (SP_REGNUM) - CALL_DUMMY_LENGTH); \
 298         from = loc + 5; \
 299         to = (int)(fun); \
 300         delta = to - from; \
 301         *((char *)(dummyname) + 1) = (delta & 0xff); \
 302         *((char *)(dummyname) + 2) = ((delta >> 8) & 0xff); \
 303         *((char *)(dummyname) + 3) = ((delta >> 16) & 0xff); \
 304         *((char *)(dummyname) + 4) = ((delta >> 24) & 0xff); \
 305 }