gdb/config/i386/tm-i386.h

   1 /* Macro definitions for GDB on an Intel i[345]86.
   2    Copyright (C) 1995, 1996 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #ifndef TM_I386_H
  21 #define TM_I386_H 1
  22
  23 #ifdef __STDC__         /* Forward decl's for prototypes */
  24 struct frame_info;
  25 struct frame_saved_regs;
  26 struct type;
  27 #endif
  28
  29 #define TARGET_BYTE_ORDER LITTLE_ENDIAN
  30
  31 /* Used for example in valprint.c:print_floating() to enable checking
  32    for NaN's */
  33
  34 #define IEEE_FLOAT
  35
  36 /* Number of traps that happen between exec'ing the shell to run an
  37    inferior, and when we finally get to the inferior code.  This is 2
  38    on most implementations. */
  39
  40 #define START_INFERIOR_TRAPS_EXPECTED 2
  41
  42 /* Offset from address of function to start of its code.
  43    Zero on most machines.  */
  44
  45 #define FUNCTION_START_OFFSET 0
  46
  47 /* Advance PC across any function entry prologue instructions to reach some
  48    "real" code.  */
  49
  50 #define SKIP_PROLOGUE(frompc)   (i386_skip_prologue (frompc))
  51
  52 extern int i386_skip_prologue PARAMS ((int));
  53
  54 /* Immediately after a function call, return the saved pc.  Can't always go
  55    through the frames for this because on some machines the new frame is not
  56    set up until the new function executes some instructions.  */
  57
  58 #define SAVED_PC_AFTER_CALL(frame) (read_memory_integer (read_register (SP_REGNUM), 4))
  59
  60 /* Stack grows downward.  */
  61
  62 #define INNER_THAN(lhs,rhs) ((lhs) < (rhs))
  63
  64 /* Sequence of bytes for breakpoint instruction.  */
  65
  66 #define BREAKPOINT {0xcc}
  67
  68 /* Amount PC must be decremented by after a breakpoint.  This is often the
  69    number of bytes in BREAKPOINT but not always. */
  70
  71 #define DECR_PC_AFTER_BREAK 1
  72
  73 /* Say how long (ordinary) registers are.  This is a piece of bogosity
  74    used in push_word and a few other places; REGISTER_RAW_SIZE is the
  75    real way to know how big a register is.  */
  76
  77 #define REGISTER_SIZE 4
  78
  79 /* Number of machine registers */
  80
  81 #define NUM_FREGS 0 /*8*/               /* Number of FP regs */
  82 #define NUM_REGS (16 + NUM_FREGS)       /* Basic i*86 regs + FP regs */
  83
  84 /* Initializer for an array of names of registers.  There should be at least
  85    NUM_REGS strings in this initializer.  Any excess ones are simply ignored.
  86    The order of the first 8 registers must match the compiler's numbering
  87    scheme (which is the same as the 386 scheme) and also regmap in the various
  88    *-nat.c files. */
  89
  90 #define REGISTER_NAMES { "eax",   "ecx",    "edx",   "ebx", \
  91                          "esp",   "ebp",    "esi",   "edi", \
  92                          "eip",   "eflags", "cs",    "ss", \
  93                          "ds",    "es",     "fs",    "gs", \
  94                          "st0",   "st1",    "st2",   "st3", \
  95                          "st4",   "st5",    "st6",   "st7", \
  96                          }
  97
  98 /* Register numbers of various important registers.
  99    Note that some of these values are "real" register numbers,
 100    and correspond to the general registers of the machine,
 101    and some are "phony" register numbers which are too large
 102    to be actual register numbers as far as the user is concerned
 103    but do serve to get the desired values when passed to read_register.  */
 104
 105 #define FP_REGNUM 5     /* (ebp) Contains address of executing stack frame */
 106 #define SP_REGNUM 4     /* (usp) Contains address of top of stack */
 107 #define PC_REGNUM 8     /* (eip) Contains program counter */
 108 #define PS_REGNUM 9     /* (ps)  Contains processor status */
 109
 110 #define FP0_REGNUM 16   /* (st0) 387 register */
 111 #define FPC_REGNUM 25   /* 80387 control register */
 112
 113 /* Total amount of space needed to store our copies of the machine's register
 114    state, the array `registers'. */
 115
 116 #define REGISTER_BYTES ((NUM_REGS - NUM_FREGS)*4 + NUM_FREGS*10)
 117
 118 /* Index within `registers' of the first byte of the space for register N. */
 119
 120 #define REGISTER_BYTE(N) \
 121   (((N) < FP0_REGNUM) ? ((N) * 4) : ((((N) - FP0_REGNUM) * 10) + 64))
 122
 123 /* Number of bytes of storage in the actual machine representation for
 124    register N.  All registers are 4 bytes, except 387 st(0) - st(7),
 125    which are 80 bits each. */
 126
 127 #define REGISTER_RAW_SIZE(N) (((N) < FP0_REGNUM) ? 4 : 10)
 128
 129 /* Largest value REGISTER_RAW_SIZE can have.  */
 130
 131 #define MAX_REGISTER_RAW_SIZE 10
 132
 133 /* Number of bytes of storage in the program's representation
 134    for register N. */
 135
 136 #define REGISTER_VIRTUAL_SIZE(N) (((N) < FP0_REGNUM) ? 4 : 8)
 137
 138 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 139
 140 #define MAX_REGISTER_VIRTUAL_SIZE 8
 141
 142 /* Return the GDB type object for the "standard" data type of data in
 143    register N.  Perhaps si and di should go here, but potentially they
 144    could be used for things other than address.  */
 145
 146 #define REGISTER_VIRTUAL_TYPE(N) \
 147   (((N) == PC_REGNUM || (N) == FP_REGNUM || (N) == SP_REGNUM) \
 148    ? lookup_pointer_type (builtin_type_void) \
 149    : (((N) < FP0_REGNUM) \
 150       ? builtin_type_int \
 151       : builtin_type_double))
 152
 153 /* Store the address of the place in which to copy the structure the
 154    subroutine will return.  This is called from call_function. */
 155
 156 #define STORE_STRUCT_RETURN(ADDR, SP) \
 157   { char buf[REGISTER_SIZE];    \
 158     (SP) -= sizeof (ADDR);      \
 159     store_address (buf, sizeof (ADDR), ADDR);   \
 160     write_memory ((SP), buf, sizeof (ADDR)); }
 161
 162 /* Extract from an array REGBUF containing the (raw) register state
 163    a function return value of type TYPE, and copy that, in virtual format,
 164    into VALBUF.  */
 165
 166 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 167    i386_extract_return_value ((TYPE),(REGBUF),(VALBUF))
 168
 169 extern void i386_extract_return_value PARAMS ((struct type *, char [], char *));
 170
 171 /* Write into appropriate registers a function return value of type TYPE, given
 172    in virtual format.  */
 173
 174 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 175   {                                                                          \
 176     if (TYPE_CODE (TYPE) == TYPE_CODE_FLT)                                   \
 177       write_register_bytes (REGISTER_BYTE (FP0_REGNUM), (VALBUF),            \
 178                             TYPE_LENGTH (TYPE));                             \
 179     else                                                                     \
 180       write_register_bytes (0, (VALBUF), TYPE_LENGTH (TYPE));                \
 181   }
 182
 183 /* Extract from an array REGBUF containing the (raw) register state the address
 184    in which a function should return its structure value, as a CORE_ADDR (or an
 185    expression that can be used as one).  */
 186
 187 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 188
 189 /* The following redefines make backtracing through sigtramp work.
 190    They manufacture a fake sigtramp frame and obtain the saved pc in sigtramp
 191    from the sigcontext structure which is pushed by the kernel on the
 192    user stack, along with a pointer to it.  */
 193
 194 /* FRAME_CHAIN takes a frame's nominal address and produces the frame's
 195    chain-pointer.
 196    In the case of the i386, the frame's nominal address
 197    is the address of a 4-byte word containing the calling frame's address.  */
 198
 199 #define FRAME_CHAIN(thisframe)  \
 200   ((thisframe)->signal_handler_caller \
 201    ? (thisframe)->frame \
 202    : (!inside_entry_file ((thisframe)->pc) \
 203       ? read_memory_integer ((thisframe)->frame, 4) \
 204       : 0))
 205
 206 /* A macro that tells us whether the function invocation represented
 207    by FI does not have a frame on the stack associated with it.  If it
 208    does not, FRAMELESS is set to 1, else 0.  */
 209
 210 #define FRAMELESS_FUNCTION_INVOCATION(FI) \
 211      (((FI)->signal_handler_caller) ? 0 : frameless_look_for_prologue(FI))
 212
 213 /* Saved Pc.  Get it from sigcontext if within sigtramp.  */
 214
 215 #define FRAME_SAVED_PC(FRAME) \
 216   (((FRAME)->signal_handler_caller \
 217     ? sigtramp_saved_pc (FRAME) \
 218     : read_memory_integer ((FRAME)->frame + 4, 4)) \
 219    )
 220
 221 extern CORE_ADDR sigtramp_saved_pc PARAMS ((struct frame_info *));
 222
 223 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 224
 225 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 226
 227 /* Return number of args passed to a frame.  Can return -1, meaning no way
 228    to tell, which is typical now that the C compiler delays popping them.  */
 229
 230 #define FRAME_NUM_ARGS(fi) (i386_frame_num_args(fi))
 231
 232 extern int i386_frame_num_args PARAMS ((struct frame_info *));
 233
 234 /* Return number of bytes at start of arglist that are not really args.  */
 235
 236 #define FRAME_ARGS_SKIP 8
 237
 238 /* Put here the code to store, into a struct frame_saved_regs,
 239    the addresses of the saved registers of frame described by FRAME_INFO.
 240    This includes special registers such as pc and fp saved in special
 241    ways in the stack frame.  sp is even more special:
 242    the address we return for it IS the sp for the next frame.  */
 243
 244 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 245 { i386_frame_find_saved_regs ((frame_info), &(frame_saved_regs)); }
 246
 247 extern void i386_frame_find_saved_regs PARAMS ((struct frame_info *,
 248                                                 struct frame_saved_regs *));
 249
 250 \f
 251 /* Things needed for making the inferior call functions.  */
 252
 253 /* Push an empty stack frame, to record the current PC, etc.  */
 254
 255 #define PUSH_DUMMY_FRAME { i386_push_dummy_frame (); }
 256
 257 extern void i386_push_dummy_frame PARAMS ((void));
 258
 259 /* Discard from the stack the innermost frame, restoring all registers.  */
 260
 261 #define POP_FRAME  { i386_pop_frame (); }
 262
 263 extern void i386_pop_frame PARAMS ((void));
 264
 265 \f
 266 /* this is
 267  *   call 11223344 (32 bit relative)
 268  *   int3
 269  */
 270
 271 #define CALL_DUMMY { 0x223344e8, 0xcc11 }
 272
 273 #define CALL_DUMMY_LENGTH 8
 274
 275 #define CALL_DUMMY_START_OFFSET 0  /* Start execution at beginning of dummy */
 276
 277 #define CALL_DUMMY_BREAKPOINT_OFFSET 5
 278
 279 /* Insert the specified number of args and function address
 280    into a call sequence of the above form stored at DUMMYNAME.  */
 281
 282 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)   \
 283 { \
 284         int from, to, delta, loc; \
 285         loc = (int)(read_register (SP_REGNUM) - CALL_DUMMY_LENGTH); \
 286         from = loc + 5; \
 287         to = (int)(fun); \
 288         delta = to - from; \
 289         *((char *)(dummyname) + 1) = (delta & 0xff); \
 290         *((char *)(dummyname) + 2) = ((delta >> 8) & 0xff); \
 291         *((char *)(dummyname) + 3) = ((delta >> 16) & 0xff); \
 292         *((char *)(dummyname) + 4) = ((delta >> 24) & 0xff); \
 293 }
 294
 295 extern void print_387_control_word PARAMS ((unsigned int));
 296 extern void print_387_status_word PARAMS ((unsigned int));
 297
 298 /* Offset from SP to first arg on stack at first instruction of a function */
 299
 300 #define SP_ARG0 (1 * 4)
 301
 302 #endif /* ifndef TM_I386_H */