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., 675 Mass Ave, Cambridge, MA 02139, 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)   {(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 <
  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 /* Nonzero if instruction at PC is a return instruction.  */
  74
  75 #define ABOUT_TO_RETURN(pc) (read_memory_integer ((pc), 1) == 0xc3)
  76
  77 /* Say how long (ordinary) registers are.  This is a piece of bogosity
  78    used in push_word and a few other places; REGISTER_RAW_SIZE is the
  79    real way to know how big a register is.  */
  80
  81 #define REGISTER_SIZE 4
  82
  83 /* Number of machine registers */
  84
  85 #define NUM_FREGS 0 /*8*/               /* Number of FP regs */
  86 #define NUM_REGS (16 + NUM_FREGS)       /* Basic i*86 regs + FP regs */
  87
  88 /* Initializer for an array of names of registers.  There should be at least
  89    NUM_REGS strings in this initializer.  Any excess ones are simply ignored.
  90    The order of the first 8 registers must match the compiler's numbering
  91    scheme (which is the same as the 386 scheme) and also regmap in the various
  92    *-nat.c files. */
  93
  94 #define REGISTER_NAMES { "eax",   "ecx",    "edx",   "ebx", \
  95                          "esp",   "ebp",    "esi",   "edi", \
  96                          "eip",   "eflags", "cs",    "ss", \
  97                          "ds",    "es",     "fs",    "gs", \
  98                          "st0",   "st1",    "st2",   "st3", \
  99                          "st4",   "st5",    "st6",   "st7", \
 100                          }
 101
 102 /* Register numbers of various important registers.
 103    Note that some of these values are "real" register numbers,
 104    and correspond to the general registers of the machine,
 105    and some are "phony" register numbers which are too large
 106    to be actual register numbers as far as the user is concerned
 107    but do serve to get the desired values when passed to read_register.  */
 108
 109 #define FP_REGNUM 5     /* (ebp) Contains address of executing stack frame */
 110 #define SP_REGNUM 4     /* (usp) Contains address of top of stack */
 111 #define PC_REGNUM 8     /* (eip) Contains program counter */
 112 #define PS_REGNUM 9     /* (ps)  Contains processor status */
 113
 114 #define FP0_REGNUM 16   /* (st0) 387 register */
 115 #define FPC_REGNUM 25   /* 80387 control register */
 116
 117 /* Total amount of space needed to store our copies of the machine's register
 118    state, the array `registers'. */
 119
 120 #define REGISTER_BYTES ((NUM_REGS - NUM_FREGS)*4 + NUM_FREGS*10)
 121
 122 /* Index within `registers' of the first byte of the space for register N. */
 123
 124 #define REGISTER_BYTE(N) \
 125   (((N) < FP0_REGNUM) ? ((N) * 4) : ((((N) - FP0_REGNUM) * 10) + 64))
 126
 127 /* Number of bytes of storage in the actual machine representation for
 128    register N.  All registers are 4 bytes, except 387 st(0) - st(7),
 129    which are 80 bits each. */
 130
 131 #define REGISTER_RAW_SIZE(N) (((N) < FP0_REGNUM) ? 4 : 10)
 132
 133 /* Largest value REGISTER_RAW_SIZE can have.  */
 134
 135 #define MAX_REGISTER_RAW_SIZE 10
 136
 137 /* Number of bytes of storage in the program's representation
 138    for register N. */
 139
 140 #define REGISTER_VIRTUAL_SIZE(N) (((N) < FP0_REGNUM) ? 4 : 8)
 141
 142 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 143
 144 #define MAX_REGISTER_VIRTUAL_SIZE 8
 145
 146 /* Return the GDB type object for the "standard" data type of data in
 147    register N.  Perhaps si and di should go here, but potentially they
 148    could be used for things other than address.  */
 149
 150 #define REGISTER_VIRTUAL_TYPE(N) \
 151   (((N) == PC_REGNUM || (N) == FP_REGNUM || (N) == SP_REGNUM) \
 152    ? lookup_pointer_type (builtin_type_void) \
 153    : (((N) < FP0_REGNUM) \
 154       ? builtin_type_int \
 155       : builtin_type_double))
 156
 157 /* Store the address of the place in which to copy the structure the
 158    subroutine will return.  This is called from call_function. */
 159
 160 #define STORE_STRUCT_RETURN(ADDR, SP) \
 161   { (SP) -= sizeof (ADDR);              \
 162     write_memory ((SP), (char *) &(ADDR), sizeof (ADDR)); }
 163
 164 /* Extract from an array REGBUF containing the (raw) register state
 165    a function return value of type TYPE, and copy that, in virtual format,
 166    into VALBUF.  */
 167
 168 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 169    i386_extract_return_value ((TYPE),(REGBUF),(VALBUF))
 170
 171 extern void i386_extract_return_value PARAMS ((struct type *, char [], char *));
 172
 173 /* Write into appropriate registers a function return value of type TYPE, given
 174    in virtual format.  */
 175
 176 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 177   {                                                                          \
 178     if (TYPE_CODE (TYPE) == TYPE_CODE_FLT)                                   \
 179       write_register_bytes (REGISTER_BYTE (FP0_REGNUM), (VALBUF),            \
 180                             TYPE_LENGTH (TYPE));                             \
 181     else                                                                     \
 182       write_register_bytes (0, (VALBUF), TYPE_LENGTH (TYPE));                \
 183   }
 184
 185 /* Extract from an array REGBUF containing the (raw) register state the address
 186    in which a function should return its structure value, as a CORE_ADDR (or an
 187    expression that can be used as one).  */
 188
 189 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 190
 191 /* The following redefines make backtracing through sigtramp work.
 192    They manufacture a fake sigtramp frame and obtain the saved pc in sigtramp
 193    from the sigcontext structure which is pushed by the kernel on the
 194    user stack, along with a pointer to it.  */
 195
 196 /* FRAME_CHAIN takes a frame's nominal address and produces the frame's
 197    chain-pointer.
 198    In the case of the i386, the frame's nominal address
 199    is the address of a 4-byte word containing the calling frame's address.  */
 200
 201 #define FRAME_CHAIN(thisframe)  \
 202   ((thisframe)->signal_handler_caller \
 203    ? (thisframe)->frame \
 204    : (!inside_entry_file ((thisframe)->pc) \
 205       ? read_memory_integer ((thisframe)->frame, 4) \
 206       : 0))
 207
 208 /* A macro that tells us whether the function invocation represented
 209    by FI does not have a frame on the stack associated with it.  If it
 210    does not, FRAMELESS is set to 1, else 0.  */
 211
 212 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 213   do { \
 214     if ((FI)->signal_handler_caller) \
 215       (FRAMELESS) = 0; \
 216     else \
 217       (FRAMELESS) = frameless_look_for_prologue(FI); \
 218   } while (0)
 219
 220 /* Saved Pc.  Get it from sigcontext if within sigtramp.  */
 221
 222 #define FRAME_SAVED_PC(FRAME) \
 223   (((FRAME)->signal_handler_caller \
 224     ? sigtramp_saved_pc (FRAME) \
 225     : read_memory_integer ((FRAME)->frame + 4, 4)) \
 226    )
 227
 228 extern CORE_ADDR sigtramp_saved_pc PARAMS ((struct frame_info *));
 229
 230 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 231
 232 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 233
 234 /* Return number of args passed to a frame.  Can return -1, meaning no way
 235    to tell, which is typical now that the C compiler delays popping them.  */
 236
 237 #define FRAME_NUM_ARGS(numargs, fi) (numargs) = i386_frame_num_args(fi)
 238
 239 extern int i386_frame_num_args PARAMS ((struct frame_info *));
 240
 241 /* Return number of bytes at start of arglist that are not really args.  */
 242
 243 #define FRAME_ARGS_SKIP 8
 244
 245 /* Put here the code to store, into a struct frame_saved_regs,
 246    the addresses of the saved registers of frame described by FRAME_INFO.
 247    This includes special registers such as pc and fp saved in special
 248    ways in the stack frame.  sp is even more special:
 249    the address we return for it IS the sp for the next frame.  */
 250
 251 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 252 { i386_frame_find_saved_regs ((frame_info), &(frame_saved_regs)); }
 253
 254 extern void i386_frame_find_saved_regs PARAMS ((struct frame_info *,
 255                                                 struct frame_saved_regs *));
 256
 257 \f
 258 /* Things needed for making the inferior call functions.  */
 259
 260 /* Push an empty stack frame, to record the current PC, etc.  */
 261
 262 #define PUSH_DUMMY_FRAME { i386_push_dummy_frame (); }
 263
 264 extern void i386_push_dummy_frame PARAMS ((void));
 265
 266 /* Discard from the stack the innermost frame, restoring all registers.  */
 267
 268 #define POP_FRAME  { i386_pop_frame (); }
 269
 270 extern void i386_pop_frame PARAMS ((void));
 271
 272 \f
 273 /* this is
 274  *   call 11223344 (32 bit relative)
 275  *   int3
 276  */
 277
 278 #define CALL_DUMMY { 0x223344e8, 0xcc11 }
 279
 280 #define CALL_DUMMY_LENGTH 8
 281
 282 #define CALL_DUMMY_START_OFFSET 0  /* Start execution at beginning of dummy */
 283
 284 #define CALL_DUMMY_BREAKPOINT_OFFSET 5
 285
 286 /* Insert the specified number of args and function address
 287    into a call sequence of the above form stored at DUMMYNAME.  */
 288
 289 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)   \
 290 { \
 291         int from, to, delta, loc; \
 292         loc = (int)(read_register (SP_REGNUM) - CALL_DUMMY_LENGTH); \
 293         from = loc + 5; \
 294         to = (int)(fun); \
 295         delta = to - from; \
 296         *((char *)(dummyname) + 1) = (delta & 0xff); \
 297         *((char *)(dummyname) + 2) = ((delta >> 8) & 0xff); \
 298         *((char *)(dummyname) + 3) = ((delta >> 16) & 0xff); \
 299         *((char *)(dummyname) + 4) = ((delta >> 24) & 0xff); \
 300 }
 301
 302 extern void print_387_control_word PARAMS ((unsigned int));
 303 extern void print_387_status_word PARAMS ((unsigned int));
 304
 305 /* Offset from SP to first arg on stack at first instruction of a function */
 306
 307 #define SP_ARG0 (1 * 4)
 308
 309 #endif /* ifndef TM_I386_H */