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