gdb/m-vax.h

   1 /* Definitions to make GDB run on a vax under 4.2bsd.
   2    Copyright (C) 1986, 1987 Free Software Foundation, Inc.
   3
   4 GDB is distributed in the hope that it will be useful, but WITHOUT ANY
   5 WARRANTY.  No author or distributor accepts responsibility to anyone
   6 for the consequences of using it or for whether it serves any
   7 particular purpose or works at all, unless he says so in writing.
   8 Refer to the GDB General Public License for full details.
   9
  10 Everyone is granted permission to copy, modify and redistribute GDB,
  11 but only under the conditions described in the GDB General Public
  12 License.  A copy of this license is supposed to have been given to you
  13 along with GDB so you can know your rights and responsibilities.  It
  14 should be in a file named COPYING.  Among other things, the copyright
  15 notice and this notice must be preserved on all copies.
  16
  17 In other words, go ahead and share GDB, but don't try to stop
  18 anyone else from sharing it farther.  Help stamp out software hoarding!
  19 */
  20
  21 #ifndef vax
  22 #define vax
  23 #endif
  24
  25 /* Get rid of any system-imposed stack limit if possible.  */
  26
  27 #define SET_STACK_LIMIT_HUGE
  28
  29 /* Define this if the C compiler puts an underscore at the front
  30    of external names before giving them to the linker.  */
  31
  32 #define NAMES_HAVE_UNDERSCORE
  33
  34 /* Debugger information will be in DBX format.  */
  35
  36 #define READ_DBX_FORMAT
  37
  38 /* Offset from address of function to start of its code.
  39    Zero on most machines.  */
  40
  41 #define FUNCTION_START_OFFSET 2
  42
  43 /* Advance PC across any function entry prologue instructions
  44    to reach some "real" code.  */
  45
  46 #define SKIP_PROLOGUE(pc)       \
  47 { register int op = (unsigned char) read_memory_integer (pc, 1);  \
  48   if (op == 0x11) pc += 2;  /* skip brb */                        \
  49   if (op == 0x31) pc += 3;  /* skip brw */                        \
  50   if (op == 0xC2 &&                                               \
  51       ((unsigned char) read_memory_integer (pc+2, 1)) == 0x5E)    \
  52     pc += 3;  /* skip subl2 */                                    \
  53   if (op == 0x9E &&                                               \
  54       ((unsigned char) read_memory_integer (pc+1, 1)) == 0xAE &&  \
  55       ((unsigned char) read_memory_integer(pc+3, 1)) == 0x5E)     \
  56      pc += 4;  /* skip movab */                                   \
  57   if (op == 0x9E &&                                               \
  58       ((unsigned char) read_memory_integer (pc+1, 1)) == 0xCE &&  \
  59       ((unsigned char) read_memory_integer(pc+4, 1)) == 0x5E)     \
  60     pc += 5;  /* skip movab */                                    \
  61   if (op == 0x9E &&                                               \
  62       ((unsigned char) read_memory_integer (pc+1, 1)) == 0xEE &&  \
  63       ((unsigned char) read_memory_integer(pc+6, 1)) == 0x5E)     \
  64     pc += 7;  /* skip movab */                                    \
  65 }
  66
  67 /* Immediately after a function call, return the saved pc.
  68    Can't always go through the frames for this because on some machines
  69    the new frame is not set up until the new function executes
  70    some instructions.  */
  71
  72 #define SAVED_PC_AFTER_CALL(frame) FRAME_SAVED_PC(frame)
  73
  74 /* This is the amount to subtract from u.u_ar0
  75    to get the offset in the core file of the register values.  */
  76
  77 #define KERNEL_U_ADDR (0x80000000 - (UPAGES * NBPG))
  78
  79 /* Address of end of stack space.  */
  80
  81 #define STACK_END_ADDR (0x80000000 - (UPAGES * NBPG))
  82
  83 /* Stack grows downward.  */
  84
  85 #define INNER_THAN <
  86
  87 /* Sequence of bytes for breakpoint instruction.  */
  88
  89 #define BREAKPOINT {3}
  90
  91 /* Amount PC must be decremented by after a breakpoint.
  92    This is often the number of bytes in BREAKPOINT
  93    but not always.  */
  94
  95 #define DECR_PC_AFTER_BREAK 0
  96
  97 /* Nonzero if instruction at PC is a return instruction.  */
  98
  99 #define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 1) == 04)
 100
 101 /* Return 1 if P points to an invalid floating point value.
 102    LEN is the length in bytes -- not relevant on the Vax.  */
 103
 104 #define INVALID_FLOAT(p, len) ((*(short *) p & 0xff80) == 0x8000)
 105
 106 /* Largest integer type */
 107 #define LONGEST long
 108
 109 /* Name of the builtin type for the LONGEST type above. */
 110 #define BUILTIN_TYPE_LONGEST builtin_type_long
 111
 112 /* Say how long (ordinary) registers are.  */
 113
 114 #define REGISTER_TYPE long
 115
 116 /* Number of machine registers */
 117
 118 #define NUM_REGS 17
 119
 120 /* Initializer for an array of names of registers.
 121    There should be NUM_REGS strings in this initializer.  */
 122
 123 #define REGISTER_NAMES {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc", "ps"}
 124
 125 /* Register numbers of various important registers.
 126    Note that some of these values are "real" register numbers,
 127    and correspond to the general registers of the machine,
 128    and some are "phony" register numbers which are too large
 129    to be actual register numbers as far as the user is concerned
 130    but do serve to get the desired values when passed to read_register.  */
 131
 132 #define AP_REGNUM 12
 133 #define FP_REGNUM 13            /* Contains address of executing stack frame */
 134 #define SP_REGNUM 14            /* Contains address of top of stack */
 135 #define PC_REGNUM 15            /* Contains program counter */
 136 #define PS_REGNUM 16            /* Contains processor status */
 137
 138 #define REGISTER_U_ADDR(addr, blockend, regno)          \
 139 { addr = blockend - 0110 + regno * 4;                   \
 140   if (regno == PC_REGNUM) addr = blockend - 8;          \
 141   if (regno == PS_REGNUM) addr = blockend - 4;          \
 142   if (regno == FP_REGNUM) addr = blockend - 0120;       \
 143   if (regno == AP_REGNUM) addr = blockend - 0124;       \
 144   if (regno == SP_REGNUM) addr = blockend - 20; }
 145
 146 /* Total amount of space needed to store our copies of the machine's
 147    register state, the array `registers'.  */
 148 #define REGISTER_BYTES (17*4)
 149
 150 /* Index within `registers' of the first byte of the space for
 151    register N.  */
 152
 153 #define REGISTER_BYTE(N) ((N) * 4)
 154
 155 /* Number of bytes of storage in the actual machine representation
 156    for register N.  On the vax, all regs are 4 bytes.  */
 157
 158 #define REGISTER_RAW_SIZE(N) 4
 159
 160 /* Number of bytes of storage in the program's representation
 161    for register N.  On the vax, all regs are 4 bytes.  */
 162
 163 #define REGISTER_VIRTUAL_SIZE(N) 4
 164
 165 /* Largest value REGISTER_RAW_SIZE can have.  */
 166
 167 #define MAX_REGISTER_RAW_SIZE 4
 168
 169 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 170
 171 #define MAX_REGISTER_VIRTUAL_SIZE 4
 172
 173 /* Nonzero if register N requires conversion
 174    from raw format to virtual format.  */
 175
 176 #define REGISTER_CONVERTIBLE(N) 0
 177
 178 /* Convert data from raw format for register REGNUM
 179    to virtual format for register REGNUM.  */
 180
 181 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO)     \
 182   bcopy ((FROM), (TO), 4);
 183
 184 /* Convert data from virtual format for register REGNUM
 185    to raw format for register REGNUM.  */
 186
 187 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
 188   bcopy ((FROM), (TO), 4);
 189
 190 /* Return the GDB type object for the "standard" data type
 191    of data in register N.  */
 192
 193 #define REGISTER_VIRTUAL_TYPE(N) builtin_type_int
 194
 195 /* Store the address of the place in which to copy the structure the
 196    subroutine will return.  This is called from call_function. */
 197
 198 #define STORE_STRUCT_RETURN(ADDR, SP) \
 199   { write_register (1, (ADDR)); }
 200
 201 /* Extract from an array REGBUF containing the (raw) register state
 202    a function return value of type TYPE, and copy that, in virtual format,
 203    into VALBUF.  */
 204
 205 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 206   bcopy (REGBUF, VALBUF, TYPE_LENGTH (TYPE))
 207
 208 /* Write into appropriate registers a function return value
 209    of type TYPE, given in virtual format.  */
 210
 211 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 212   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 213
 214 /* Extract from an array REGBUF containing the (raw) register state
 215    the address in which a function should return its structure value,
 216    as a CORE_ADDR (or an expression that can be used as one).  */
 217
 218 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 219
 220 /* Compensate for lack of `vprintf' function.  */
 221 #define vprintf(format, ap) _doprnt (format, ap, stdout)
 222 \f
 223 /* Describe the pointer in each stack frame to the previous stack frame
 224    (its caller).  */
 225
 226 /* FRAME_CHAIN takes a frame's nominal address
 227    and produces the frame's chain-pointer.
 228
 229    FRAME_CHAIN_COMBINE takes the chain pointer and the frame's nominal address
 230    and produces the nominal address of the caller frame.
 231
 232    However, if FRAME_CHAIN_VALID returns zero,
 233    it means the given frame is the outermost one and has no caller.
 234    In that case, FRAME_CHAIN_COMBINE is not used.  */
 235
 236 /* In the case of the Vax, the frame's nominal address is the FP value,
 237    and 12 bytes later comes the saved previous FP value as a 4-byte word.  */
 238
 239 #define FRAME_CHAIN(thisframe)  (read_memory_integer ((thisframe)->frame + 12, 4))
 240
 241 #define FRAME_CHAIN_VALID(chain, thisframe) \
 242   (chain != 0 && (FRAME_SAVED_PC (thisframe) >= first_object_file_end))
 243
 244 #define FRAME_CHAIN_COMBINE(chain, thisframe) (chain)
 245
 246 /* Define other aspects of the stack frame.  */
 247
 248 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 16, 4))
 249
 250 /* Cannot find the AP register value directly from the FP value.
 251    Must find it saved in the frame called by this one, or in the AP register
 252    for the innermost frame.  */
 253 #define FRAME_ARGS_ADDRESS(fi) \
 254  (((fi)->next_frame                                  \
 255    ? read_memory_integer ((fi)->next_frame + 8, 4)   \
 256    : read_register (AP_REGNUM)))
 257
 258 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 259
 260 /* Return number of args passed to a frame.
 261    Can return -1, meaning no way to tell.  */
 262
 263 #define FRAME_NUM_ARGS(numargs, fi)  \
 264 { numargs = (0xff & read_memory_integer (FRAME_ARGS_ADDRESS (fi), 1)); }
 265
 266 /* Return number of bytes at start of arglist that are not really args.  */
 267
 268 #define FRAME_ARGS_SKIP 4
 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 { register int regnum;     \
 278   register int regmask = read_memory_integer ((frame_info)->frame+4, 4) >> 16; \
 279   register CORE_ADDR next_addr;     \
 280   bzero (&frame_saved_regs, sizeof frame_saved_regs);     \
 281   next_addr = (frame_info)->frame + 16;     \
 282   /* Regmask's low bit is for register 0,     \
 283      which is the first one that would be pushed.  */     \
 284   for (regnum = 0; regnum < 12; regnum++, regmask >>= 1)  \
 285     (frame_saved_regs).regs[regnum] = (regmask & 1) ? (next_addr += 4) : 0;  \
 286   (frame_saved_regs).regs[SP_REGNUM] = next_addr + 4;  \
 287   if (read_memory_integer ((frame_info)->frame + 4, 4) & 0x20000000)   \
 288     (frame_saved_regs).regs[SP_REGNUM] += 4 + 4 * read_memory_integer (next_addr + 4, 4);  \
 289   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 16;  \
 290   (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame + 12;  \
 291   (frame_saved_regs).regs[AP_REGNUM] = (frame_info)->frame + 8;  \
 292   (frame_saved_regs).regs[PS_REGNUM] = (frame_info)->frame + 4;  \
 293 }
 294 \f
 295 /* Things needed for making the inferior call functions.  */
 296
 297 /* Push an empty stack frame, to record the current PC, etc.  */
 298
 299 #define PUSH_DUMMY_FRAME \
 300 { register CORE_ADDR sp = read_register (SP_REGNUM);\
 301   register int regnum;                              \
 302   sp = push_word (sp, 0); /* arglist */             \
 303   for (regnum = 11; regnum >= 0; regnum--)          \
 304     sp = push_word (sp, read_register (regnum));    \
 305   sp = push_word (sp, read_register (PC_REGNUM));   \
 306   sp = push_word (sp, read_register (FP_REGNUM));   \
 307   sp = push_word (sp, read_register (AP_REGNUM));   \
 308   sp = push_word (sp, (read_register (PS_REGNUM) & 0xffef)   \
 309                       + 0x2fff0000);                \
 310   sp = push_word (sp, 0);                           \
 311   write_register (SP_REGNUM, sp);                   \
 312   write_register (FP_REGNUM, sp);                   \
 313   write_register (AP_REGNUM, sp + 17 * sizeof (int)); }
 314
 315 /* Discard from the stack the innermost frame, restoring all registers.  */
 316
 317 #define POP_FRAME  \
 318 { register CORE_ADDR fp = read_register (FP_REGNUM);             \
 319   register int regnum;                                           \
 320   register int regmask = read_memory_integer (fp + 4, 4);        \
 321   write_register (PS_REGNUM,                                     \
 322                   (regmask & 0xffff)                             \
 323                   | (read_register (PS_REGNUM) & 0xffff0000));   \
 324   write_register (PC_REGNUM, read_memory_integer (fp + 16, 4));  \
 325   write_register (FP_REGNUM, read_memory_integer (fp + 12, 4));  \
 326   write_register (AP_REGNUM, read_memory_integer (fp + 8, 4));   \
 327   fp += 16;                                                      \
 328   for (regnum = 0; regnum < 12; regnum++)                        \
 329     if (regmask & (0x10000 << regnum))                           \
 330       write_register (regnum, read_memory_integer (fp += 4, 4)); \
 331   fp = fp + 4 + ((regmask >> 30) & 3);                           \
 332   if (regmask & 0x20000000)                                      \
 333     { regnum = read_memory_integer (fp, 4);                      \
 334       fp += (regnum + 1) * 4; }                                  \
 335   write_register (SP_REGNUM, fp);                                \
 336   flush_cached_frames ();                                        \
 337   set_current_frame (create_new_frame (read_register (FP_REGNUM),\
 338                                         read_pc ())); }
 339
 340 /* This sequence of words is the instructions
 341      calls #69, @#32323232
 342      bpt
 343    Note this is 8 bytes.  */
 344
 345 #define CALL_DUMMY {0x329f69fb, 0x03323232}
 346
 347 #define CALL_DUMMY_START_OFFSET 0  /* Start execution at beginning of dummy */
 348
 349 /* Insert the specified number of args and function address
 350    into a call sequence of the above form stored at DUMMYNAME.  */
 351
 352 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, type)   \
 353 { *((char *) dummyname + 1) = nargs;            \
 354   *(int *)((char *) dummyname + 3) = fun; }
 355 \f
 356 /* Interface definitions for kernel debugger KDB.  */
 357
 358 /* Map machine fault codes into signal numbers.
 359    First subtract 0, divide by 4, then index in a table.
 360    Faults for which the entry in this table is 0
 361    are not handled by KDB; the program's own trap handler
 362    gets to handle then.  */
 363
 364 #define FAULT_CODE_ORIGIN 0
 365 #define FAULT_CODE_UNITS 4
 366 #define FAULT_TABLE    \
 367 { 0, SIGKILL, SIGSEGV, 0, 0, 0, 0, 0, \
 368   0, 0, SIGTRAP, SIGTRAP, 0, 0, 0, 0, \
 369   0, 0, 0, 0, 0, 0, 0, 0}
 370
 371 /* Start running with a stack stretching from BEG to END.
 372    BEG and END should be symbols meaningful to the assembler.
 373    This is used only for kdb.  */
 374
 375 #define INIT_STACK(beg, end)  \
 376 { asm (".globl end");         \
 377   asm ("movl $ end, sp");      \
 378   asm ("clrl fp"); }
 379
 380 /* Push the frame pointer register on the stack.  */
 381 #define PUSH_FRAME_PTR        \
 382   asm ("pushl fp");
 383
 384 /* Copy the top-of-stack to the frame pointer register.  */
 385 #define POP_FRAME_PTR  \
 386   asm ("movl (sp), fp");
 387
 388 /* After KDB is entered by a fault, push all registers
 389    that GDB thinks about (all NUM_REGS of them),
 390    so that they appear in order of ascending GDB register number.
 391    The fault code will be on the stack beyond the last register.  */
 392
 393 #define PUSH_REGISTERS        \
 394 { asm ("pushl 8(sp)");        \
 395   asm ("pushl 8(sp)");        \
 396   asm ("pushal 0x14(sp)");    \
 397   asm ("pushr $037777"); }
 398
 399 /* Assuming the registers (including processor status) have been
 400    pushed on the stack in order of ascending GDB register number,
 401    restore them and return to the address in the saved PC register.  */
 402
 403 #define POP_REGISTERS      \
 404 { asm ("popr $037777");    \
 405   asm ("subl2 $8,(sp)");   \
 406   asm ("movl (sp),sp");    \
 407   asm ("rei"); }