gdb/tm-rs6000.h

   1 /* Parameters for target execution on an RS6000, for GDB, the GNU debugger.
   2    Copyright (C) 1986, 1987, 1989, 1991 Free Software Foundation, Inc.
   3    Contributed by IBM Corporation.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21
  22 /* A successful ptrace(continue) might return errno != 0 in this particular port
  23    of rs6000. I am not sure why. We will use this kludge and ignore it until
  24    we figure out the real problem. */
  25
  26 #define AIX_BUGGY_PTRACE_CONTINUE       \
  27 { \
  28   int ret = ptrace (PT_CONTINUE, inferior_pid, (int *)1, signal, 0); \
  29   if (errno) { \
  30 /*    printf ("ret: %d, errno: %d, signal: %d\n", ret, errno, signal); */ \
  31     errno = 0; } \
  32 }
  33
  34 extern int      symtab_relocated;
  35
  36 /* Minimum possible text address in AIX */
  37
  38 #define TEXT_SEGMENT_BASE       0x10000000
  39
  40
  41 /* text addresses in a core file does not necessarily match to symbol table,
  42    if symbol table relocation wasn't done yet. */
  43
  44 #define CORE_NEEDS_RELOCATION(PC)       \
  45   if (!symtab_relocated && !inferior_pid && (PC) >  TEXT_SEGMENT_BASE)  \
  46     (PC) -= ( TEXT_SEGMENT_BASE + text_adjustment (exec_bfd));
  47
  48 /* Conversion between a register number in stab string to actual register num. */
  49
  50 #define STAB_REG_TO_REGNUM(value)       (value)
  51
  52 /* return true if a given `pc' value is in `call dummy' function. */
  53
  54 #define PC_IN_CALL_DUMMY(STOP_PC, STOP_SP, STOP_FRAME_ADDR)     \
  55         (STOP_SP < STOP_PC && STOP_PC < STACK_END_ADDR)
  56
  57 /* For each symtab, we keep track of which BFD it came from.  */
  58 #define EXTRA_SYMTAB_INFO       \
  59         unsigned    nonreloc:1;         /* TRUE if non relocatable */
  60
  61 #define INIT_EXTRA_SYMTAB_INFO(symtab)  \
  62         symtab->nonreloc = 0;           \
  63
  64 extern unsigned int text_start, data_start;
  65 extern int inferior_pid;
  66 extern char *corefile;
  67
  68 /* setpgrp() messes up controling terminal. The other version of it
  69    requires libbsd.a. */
  70 #define setpgrp(XX,YY)          setpgid (XX, YY)
  71
  72 /* We are missing register descriptions in the system header files. Sigh! */
  73
  74 struct regs {
  75         int     gregs [32];     /* general purpose registers */
  76         int     pc;             /* program conter       */
  77         int     ps;             /* processor status, or machine state */
  78 };
  79
  80 struct fp_status {
  81         double  fpregs [32];                    /* floating GP registers */
  82 };
  83
  84 /* Define the byte order of the machine.  */
  85
  86 #define TARGET_BYTE_ORDER       BIG_ENDIAN
  87
  88 /* Define this if the C compiler puts an underscore at the front
  89    of external names before giving them to the linker.  */
  90
  91 #undef NAMES_HAVE_UNDERSCORE
  92
  93 /* Offset from address of function to start of its code.
  94    Zero on most machines.  */
  95
  96 #define FUNCTION_START_OFFSET 0
  97
  98 /* Advance PC across any function entry prologue instructions
  99    to reach some "real" code.  */
 100
 101 #define SKIP_PROLOGUE(pc)       pc = skip_prologue (pc)
 102
 103 /* If PC is in some function-call trampoline code, return the PC
 104    where the function itself actually starts.  If not, return NULL.  */
 105
 106 #define SKIP_TRAMPOLINE_CODE(pc)        skip_trampoline_code (pc)
 107
 108 /* When a child process is just starting, we sneak in and relocate
 109    the symbol table (and other stuff) after the dynamic linker has
 110    figured out where they go. But we want to do this relocation just
 111    once. */
 112
 113 extern int aix_loadInfoTextIndex;
 114
 115 #define SOLIB_CREATE_INFERIOR_HOOK()    \
 116   do {                                  \
 117     if (aix_loadInfoTextIndex == 0)     \
 118         aixcoff_relocate_symtab (pid);  \
 119   } while (0)
 120
 121
 122 /* In aix, number of the trap signals we need to skip over once the
 123    inferior process starts running is different in version 3.1 and 3.2.
 124    This will be 2 for version 3.1x, 3 for version 3.2x. */
 125
 126 #define START_INFERIOR_TRAPS_EXPECTED   aix_starting_inferior_traps ()
 127
 128 /* In aixcoff, we cannot process line numbers when we see them. This is
 129    mainly because we don't know the boundaries of the include files. So,
 130    we postpone that, and then enter and sort(?) the whole line table at
 131    once, when we are closing the current symbol table in end_symtab(). */
 132
 133 #define PROCESS_LINENUMBER_HOOK()       aix_process_linenos ()
 134
 135
 136 /* When a target process or core-file has been attached, we sneak in
 137    and figure out where the shared libraries have got to. In case there
 138    is no inferior_process exists (e.g. bringing up a core file), we can't
 139    attemtp to relocate symbol table, since we don't have information about
 140    load segments. */
 141
 142 #define SOLIB_ADD(a, b, c)      \
 143    if (inferior_pid)    aixcoff_relocate_symtab (inferior_pid)
 144
 145 /* Immediately after a function call, return the saved pc.
 146    Can't go through the frames for this because on some machines
 147    the new frame is not set up until the new function executes
 148    some instructions.  */
 149
 150 extern char registers[];
 151
 152 #define SAVED_PC_AFTER_CALL(frame)      \
 153         (*(int*)&registers[REGISTER_BYTE (LR_REGNUM)])
 154
 155 /*#define SAVED_PC_AFTER_CALL(frame)    saved_pc_after_call(frame) */
 156
 157
 158 /* Address of end of stack space.  */
 159
 160 #define STACK_END_ADDR 0x2ff80000
 161
 162 /* Stack grows downward.  */
 163
 164 #define INNER_THAN <
 165
 166 #if 0
 167 /* No, we shouldn't use this. push_arguments() should leave stack in a
 168    proper alignment! */
 169 /* Stack has strict alignment. */
 170
 171 #define STACK_ALIGN(ADDR)       (((ADDR)+7)&-8)
 172 #endif
 173
 174 /* This is how argumets pushed onto stack or passed in registers. */
 175
 176 #define PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr) \
 177   sp = push_arguments(nargs, args, sp, struct_return, struct_addr)
 178
 179 /* Sequence of bytes for breakpoint instruction.  */
 180
 181 #define BREAKPOINT {0x7d, 0x82, 0x10, 0x08}
 182
 183 /* Amount PC must be decremented by after a breakpoint.
 184    This is often the number of bytes in BREAKPOINT
 185    but not always.  */
 186
 187 #define DECR_PC_AFTER_BREAK 0
 188
 189 /* Nonzero if instruction at PC is a return instruction.  */
 190 /* Allow any of the return instructions, including a trapv and a return
 191    from interrupt.  */
 192
 193 #define ABOUT_TO_RETURN(pc)  \
 194    ((read_memory_integer (pc, 4) & 0xfe8007ff) == 0x4e800020)
 195
 196 /* Return 1 if P points to an invalid floating point value.  */
 197
 198 #define INVALID_FLOAT(p, len) 0   /* Just a first guess; not checked */
 199
 200 /* Largest integer type */
 201
 202 #define LONGEST long
 203
 204 /* Name of the builtin type for the LONGEST type above. */
 205
 206 #define BUILTIN_TYPE_LONGEST builtin_type_long
 207
 208 /* Say how long (ordinary) registers are.  */
 209
 210 #define REGISTER_TYPE long
 211
 212 /* Number of machine registers */
 213
 214 #define NUM_REGS 71
 215
 216 /* Initializer for an array of names of registers.
 217    There should be NUM_REGS strings in this initializer.  */
 218
 219 #define REGISTER_NAMES  \
 220  {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",  \
 221   "r8", "r9", "r10","r11","r12","r13","r14","r15", \
 222   "r16","r17","r18","r19","r20","r21","r22","r23", \
 223   "r24","r25","r26","r27","r28","r29","r30","r31", \
 224   "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",  \
 225   "f8", "f9", "f10","f11","f12","f13","f14","f15", \
 226   "f16","f17","f18","f19","f20","f21","f22","f23", \
 227   "f24","f25","f26","f27","f28","f29","f30","f31", \
 228   "pc", "ps", "cnd", "lr", "cnt", "xer", "mq" }
 229
 230 /* Register numbers of various important registers.
 231    Note that some of these values are "real" register numbers,
 232    and correspond to the general registers of the machine,
 233    and some are "phony" register numbers which are too large
 234    to be actual register numbers as far as the user is concerned
 235    but do serve to get the desired values when passed to read_register.  */
 236
 237 #define FP_REGNUM 1             /* Contains address of executing stack frame */
 238 #define SP_REGNUM 1             /* Contains address of top of stack */
 239 #define TOC_REGNUM 2            /* TOC register */
 240 #define FP0_REGNUM 32           /* Floating point register 0 */
 241 #define GP0_REGNUM 0            /* GPR register 0 */
 242 #define FP0_REGNUM 32           /* FPR (Floating point) register 0 */
 243 #define FPLAST_REGNUM 63        /* Last floating point register */
 244
 245 /* Special purpose registers... */
 246 /* P.S. keep these in the same order as in /usr/mstsave.h `mstsave' structure, for
 247    easier processing */
 248
 249 #define PC_REGNUM 64            /* Program counter (instruction address %iar) */
 250 #define PS_REGNUM 65            /* Processor (or machine) status (%msr) */
 251 #define CR_REGNUM 66            /* Condition register */
 252 #define LR_REGNUM 67            /* Link register */
 253 #define CTR_REGNUM 68           /* Count register */
 254 #define XER_REGNUM 69           /* Fixed point exception registers */
 255 #define MQ_REGNUM 70            /* Multiply/quotient register */
 256
 257 #define FIRST_SP_REGNUM 64      /* first special register number */
 258 #define LAST_SP_REGNUM  70      /* last special register number */
 259
 260 /* Total amount of space needed to store our copies of the machine's
 261    register state, the array `registers'.
 262
 263         32 4-byte gpr's
 264         32 8-byte fpr's
 265         7  4-byte special purpose registers,
 266
 267    total 416 bytes. Keep some extra space for now, in case to add more. */
 268
 269 #define REGISTER_BYTES 420
 270
 271
 272 /* Index within `registers' of the first byte of the space for
 273    register N.  */
 274
 275 #define REGISTER_BYTE(N)  \
 276  (                                                              \
 277   ((N) > FPLAST_REGNUM) ? ((((N) - FPLAST_REGNUM -1) * 4) + 384)\
 278   :((N) >= FP0_REGNUM) ? ((((N) - FP0_REGNUM) * 8) + 128)       \
 279   :((N) * 4) )
 280
 281 /* Number of bytes of storage in the actual machine representation
 282    for register N. */
 283 /* Note that the unsigned cast here forces the result of the
 284    subtractiion to very high positive values if N < FP0_REGNUM */
 285
 286 #define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4)
 287
 288 /* Number of bytes of storage in the program's representation
 289    for register N.  On the RS6000, all regs are 4 bytes
 290    except the floating point regs which are 8-byte doubles.  */
 291
 292 #define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4)
 293
 294 /* Largest value REGISTER_RAW_SIZE can have.  */
 295
 296 #define MAX_REGISTER_RAW_SIZE 8
 297
 298 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 299
 300 #define MAX_REGISTER_VIRTUAL_SIZE 8
 301
 302 /* convert a dbx stab register number (from `r' declaration) to a gdb REGNUM */
 303
 304 #define STAB_REG_TO_REGNUM(value)       (value)
 305
 306 /* Nonzero if register N requires conversion
 307    from raw format to virtual format.  */
 308
 309 #define REGISTER_CONVERTIBLE(N) ((N) >= FP0_REGNUM && (N) <= FPLAST_REGNUM)
 310
 311 /* Convert data from raw format for register REGNUM
 312    to virtual format for register REGNUM.  */
 313
 314 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO)     \
 315    bcopy ((FROM), (TO), REGISTER_RAW_SIZE (REGNUM))
 316
 317 /* Convert data from virtual format for register REGNUM
 318    to raw format for register REGNUM.  */
 319
 320 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
 321    bcopy ((FROM), (TO), REGISTER_RAW_SIZE (REGNUM))
 322
 323 /* Return the GDB type object for the "standard" data type
 324    of data in register N.  */
 325
 326 #define REGISTER_VIRTUAL_TYPE(N) \
 327  (((unsigned)(N) - FP0_REGNUM) < 32 ? builtin_type_double : builtin_type_int)
 328
 329 /* Store the address of the place in which to copy the structure the
 330    subroutine will return.  This is called from call_function. */
 331 /* in RS6000, struct return addresses are passed as an extra parameter in r3.
 332    In function return, callee is not responsible of returning this address back.
 333    Since gdb needs to find it, we will store in a designated variable
 334    `rs6000_struct_return_address'. */
 335
 336 extern unsigned int rs6000_struct_return_address;
 337
 338 #define STORE_STRUCT_RETURN(ADDR, SP)   \
 339   { write_register (3, (ADDR));         \
 340     rs6000_struct_return_address = (unsigned int)(ADDR); }
 341
 342 /* Extract from an array REGBUF containing the (raw) register state
 343    a function return value of type TYPE, and copy that, in virtual format,
 344    into VALBUF.  */
 345
 346 /* #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 347   bcopy (REGBUF, VALBUF, TYPE_LENGTH (TYPE)) */
 348
 349 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 350   extract_return_value(TYPE,REGBUF,VALBUF)
 351
 352 /* Write into appropriate registers a function return value
 353    of type TYPE, given in virtual format.  */
 354
 355 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 356   {                                                                     \
 357     if (TYPE_CODE (TYPE) == TYPE_CODE_FLT)                              \
 358                                                                         \
 359      /* Floating point values are returned starting from FPR1 and up.   \
 360         Say a double_double_double type could be returned in            \
 361         FPR1/FPR2/FPR3 triple. */                                       \
 362                                                                         \
 363       write_register_bytes (REGISTER_BYTE (FP0_REGNUM+1), (VALBUF),     \
 364                                                 TYPE_LENGTH (TYPE));    \
 365     else                                                                \
 366       /* Everything else is returned in GPR3 and up. */                 \
 367       write_register_bytes (REGISTER_BYTE (GP0_REGNUM+3), (VALBUF),     \
 368                                                 TYPE_LENGTH (TYPE));    \
 369   }
 370
 371
 372 /* Extract from an array REGBUF containing the (raw) register state
 373    the address in which a function should return its structure value,
 374    as a CORE_ADDR (or an expression that can be used as one).  */
 375
 376 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF)    rs6000_struct_return_address
 377
 378
 379 /* Do implement the attach and detach commands.  */
 380
 381 #define ATTACH_DETACH
 382
 383 /* infptrace.c requires those. */
 384
 385 #define PTRACE_ATTACH 30
 386 #define PTRACE_DETACH 31
 387
 388 \f
 389 /* Describe the pointer in each stack frame to the previous stack frame
 390    (its caller).  */
 391
 392 /* FRAME_CHAIN takes a frame's nominal address
 393    and produces the frame's chain-pointer.
 394
 395    However, if FRAME_CHAIN_VALID returns zero,
 396    it means the given frame is the outermost one and has no caller.  */
 397
 398 /* In the case of the RS6000, the frame's nominal address
 399    is the address of a 4-byte word containing the calling frame's address.  */
 400
 401 #define FRAME_CHAIN(thisframe)  \
 402   (outside_startup_file ((thisframe)->pc) ?     \
 403    read_memory_integer ((thisframe)->frame, 4) :\
 404    0)
 405
 406 #define FRAME_CHAIN_VALID(chain, thisframe) \
 407   (chain != 0 && (outside_startup_file (FRAME_SAVED_PC (thisframe))))
 408
 409 /* Define other aspects of the stack frame.  */
 410
 411 /* A macro that tells us whether the function invocation represented
 412    by FI does not have a frame on the stack associated with it.  If it
 413    does not, FRAMELESS is set to 1, else 0.  */
 414
 415 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 416         FRAMELESS = frameless_function_invocation (FI)
 417
 418 /* Frameless function invocation in IBM RS/6000 is half-done. It perfectly
 419    sets up a new frame, e.g. a new frame (in fact stack) pointer, etc, but it
 420    doesn't save the %pc. In the following, even though it is considered a
 421    frameless invocation, we still need to walk one frame up. */
 422
 423 #define INIT_EXTRA_FRAME_INFO(fromleaf, fi)     \
 424         if (fromleaf) {                 \
 425           int tmp = 0;                  \
 426           read_memory ((fi)->frame, &tmp, sizeof (int));        \
 427           (fi)->frame = tmp;            \
 428         }
 429
 430 #define FRAME_SAVED_PC(FRAME)           \
 431         read_memory_integer (read_memory_integer ((FRAME)->frame, 4)+8, 4)
 432
 433 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 434
 435 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 436
 437 /* Set VAL to the number of args passed to frame described by FI.
 438    Can set VAL to -1, meaning no way to tell.  */
 439
 440 /* We can't tell how many args there are
 441    now that the C compiler delays popping them.  */
 442
 443 #define FRAME_NUM_ARGS(val,fi) (val = -1)
 444
 445 /* Return number of bytes at start of arglist that are not really args.  */
 446
 447 #define FRAME_ARGS_SKIP 8       /* Not sure on this. FIXMEmgo */
 448
 449 /* Put here the code to store, into a struct frame_saved_regs,
 450    the addresses of the saved registers of frame described by FRAME_INFO.
 451    This includes special registers such as pc and fp saved in special
 452    ways in the stack frame.  sp is even more special:
 453    the address we return for it IS the sp for the next frame.  */
 454
 455 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs)             \
 456         printf ("FIXMEmgo! FRAME_FIND_SAVED_REGS() not implemented!\n")
 457 \f
 458 /* Things needed for making the inferior call functions.  */
 459
 460 /* Push an empty stack frame, to record the current PC, etc.  */
 461 /* Change these names into rs6k_{push, pop}_frame(). FIXMEmgo. */
 462
 463 #define PUSH_DUMMY_FRAME        push_dummy_frame ()
 464
 465 /* Discard from the stack the innermost frame,
 466    restoring all saved registers.  */
 467
 468 #define POP_FRAME       pop_frame ()
 469
 470 /* This sequence of words is the instructions:
 471
 472         mflr    r0              // 0x7c0802a6
 473                                 // save fpr's
 474         stfd    r?, num(r1)     // 0xd8010000 there should be 32 of this??
 475                                 // save gpr's
 476         stm     r0, num(r1)     // 0xbc010000
 477         stu     r1, num(r1)     // 0x94210000
 478
 479         // the function we want to branch might be in a different load
 480         // segment. reset the toc register. Note that the actual toc address
 481         // will be fix by fix_call_dummy () along with function address.
 482
 483         st      r2, 0x14(r1)    // 0x90410014 save toc register
 484         liu     r2, 0x1234      // 0x3c401234 reset a new toc value 0x12345678
 485         oril    r2, r2,0x5678   // 0x60425678
 486
 487                                 // load absolute address 0x12345678 to r0
 488         liu     r0, 0x1234      // 0x3c001234
 489         oril    r0, r0,0x5678   // 0x60005678
 490         mtctr   r0              // 0x7c0903a6 ctr <- r0
 491         bctrl                   // 0x4e800421 jump subroutine 0x12345678 (%ctr)
 492         cror    0xf, 0xf, 0xf   // 0x4def7b82
 493         brpt                    // 0x7d821008, breakpoint
 494         cror    0xf, 0xf, 0xf   // 0x4def7b82 (for 8 byte alignment)
 495
 496
 497   We actually start executing by saving the toc register first, since the pushing
 498   of the registers is done by PUSH_DUMMY_FRAME.  If this were real code,
 499   the arguments for the function called by the `bctrl' would be pushed
 500   between the `stu' and the `bctrl', and we could allow it to execute through.
 501   But the arguments have to be pushed by GDB after the PUSH_DUMMY_FRAME is done,
 502   and we cannot allow to push the registers again.
 503 */
 504
 505 #define CALL_DUMMY {0x7c0802a6, 0xd8010000, 0xbc010000, 0x94210000, \
 506                     0x90410014, 0x3c401234, 0x60425678,             \
 507                     0x3c001234, 0x60005678, 0x7c0903a6, 0x4e800421, \
 508                     0x4def7b82, 0x7d821008, 0x4def7b82 }
 509
 510
 511 /* keep this as multiple of 8 (%sp requires 8 byte alignment) */
 512 #define CALL_DUMMY_LENGTH 56
 513
 514 #define CALL_DUMMY_START_OFFSET 16
 515
 516 /* Insert the specified number of args and function address
 517    into a call sequence of the above form stored at DUMMYNAME.  */
 518
 519 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, using_gcc) \
 520         fix_call_dummy(dummyname, pc, fun, nargs, type)
 521
 522 /* Flag for machine-specific stuff in shared files.  FIXME */
 523 #ifndef IBM6000
 524 #define IBM6000
 525 #endif