gdb/config/a29k/tm-a29k.h

   1 /* Parameters for target machine AMD 29000, for GDB, the GNU debugger.
   2    Copyright 1990, 1991, 1993, 1994 Free Software Foundation, Inc.
   3    Contributed by Cygnus Support.  Written by Jim Kingdon.
   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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  20
  21 /* Parameters for an EB29K (a board which plugs into a PC and is
  22    accessed through EBMON software running on the PC, which we
  23    use as we'd use a remote stub (see remote-eb.c).
  24
  25    If gdb is ported to other a29k machines/systems, the
  26    machine/system-specific parts should be removed from this file (a
  27    la tm-m68k.h).  */
  28
  29 /* Byte order is configurable, but this machine runs big-endian.  */
  30 #define TARGET_BYTE_ORDER BIG_ENDIAN
  31
  32 /* Floating point uses IEEE representations.  */
  33 #define IEEE_FLOAT
  34
  35 /* Recognize our magic number.  */
  36 #define BADMAG(x) ((x).f_magic != 0572)
  37
  38 /* Offset from address of function to start of its code.
  39    Zero on most machines.  */
  40
  41 #define FUNCTION_START_OFFSET 0
  42
  43 /* Advance PC across any function entry prologue instructions
  44    to reach some "real" code.  */
  45
  46 #define SKIP_PROLOGUE(pc) \
  47   { pc = skip_prologue (pc); }
  48 CORE_ADDR skip_prologue ();
  49
  50 /* Immediately after a function call, return the saved pc.
  51    Can't go through the frames for this because on some machines
  52    the new frame is not set up until the new function executes
  53    some instructions.  */
  54
  55 #define SAVED_PC_AFTER_CALL(frame) ((frame->flags & TRANSPARENT_FRAME) \
  56                                     ? read_register (TPC_REGNUM) \
  57                                     : read_register (LR0_REGNUM))
  58
  59 /* Stack grows downward.  */
  60
  61 #define INNER_THAN <
  62
  63 /* Stack must be aligned on 32-bit boundaries when synthesizing
  64    function calls. */
  65
  66 #define STACK_ALIGN(ADDR) (((ADDR) + 3) & ~3)
  67
  68 /* Sequence of bytes for breakpoint instruction.  */
  69 /* ASNEQ 0x50, gr1, gr1
  70    The trap number 0x50 is chosen arbitrarily.
  71    We let the command line (or previously included files) override this
  72    setting.  */
  73 #ifndef BREAKPOINT
  74 #if TARGET_BYTE_ORDER == BIG_ENDIAN
  75 #define BREAKPOINT {0x72, 0x50, 0x01, 0x01}
  76 #else /* Target is little-endian.  */
  77 #define BREAKPOINT {0x01, 0x01, 0x50, 0x72}
  78 #endif /* Target is little-endian.  */
  79 #endif /* BREAKPOINT */
  80
  81 /* Amount PC must be decremented by after a breakpoint.
  82    This is often the number of bytes in BREAKPOINT
  83    but not always.  */
  84
  85 #define DECR_PC_AFTER_BREAK 0
  86
  87 /* Nonzero if instruction at PC is a return instruction.
  88    On the a29k, this is a "jmpi l0" instruction.  */
  89
  90 #define ABOUT_TO_RETURN(pc) \
  91   ((read_memory_integer (pc, 4) & 0xff0000ff) == 0xc0000080)
  92
  93 /* Say how long (ordinary) registers are.  This is a piece of bogosity
  94    used in push_word and a few other places; REGISTER_RAW_SIZE is the
  95    real way to know how big a register is.  */
  96
  97 #define REGISTER_SIZE 4
  98
  99 /* Allow the register declarations here to be overridden for remote
 100    kernel debugging.  */
 101 #if !defined (REGISTER_NAMES)
 102
 103 /* Number of machine registers */
 104
 105 #define NUM_REGS 205
 106
 107 /* Initializer for an array of names of registers.
 108    There should be NUM_REGS strings in this initializer.
 109
 110    FIXME, add floating point registers and support here.
 111
 112    Also note that this list does not attempt to deal with kernel
 113    debugging (in which the first 32 registers are gr64-gr95).  */
 114
 115 #define REGISTER_NAMES \
 116 {"gr96", "gr97", "gr98", "gr99", "gr100", "gr101", "gr102", "gr103", "gr104", \
 117  "gr105", "gr106", "gr107", "gr108", "gr109", "gr110", "gr111", "gr112", \
 118  "gr113", "gr114", "gr115", "gr116", "gr117", "gr118", "gr119", "gr120", \
 119  "gr121", "gr122", "gr123", "gr124", "gr125", "gr126", "gr127",          \
 120  "lr0", "lr1", "lr2", "lr3", "lr4", "lr5", "lr6", "lr7", "lr8", "lr9",   \
 121  "lr10", "lr11", "lr12", "lr13", "lr14", "lr15", "lr16", "lr17", "lr18", \
 122  "lr19", "lr20", "lr21", "lr22", "lr23", "lr24", "lr25", "lr26", "lr27", \
 123  "lr28", "lr29", "lr30", "lr31", "lr32", "lr33", "lr34", "lr35", "lr36", \
 124  "lr37", "lr38", "lr39", "lr40", "lr41", "lr42", "lr43", "lr44", "lr45", \
 125  "lr46", "lr47", "lr48", "lr49", "lr50", "lr51", "lr52", "lr53", "lr54", \
 126  "lr55", "lr56", "lr57", "lr58", "lr59", "lr60", "lr61", "lr62", "lr63", \
 127  "lr64", "lr65", "lr66", "lr67", "lr68", "lr69", "lr70", "lr71", "lr72", \
 128  "lr73", "lr74", "lr75", "lr76", "lr77", "lr78", "lr79", "lr80", "lr81", \
 129  "lr82", "lr83", "lr84", "lr85", "lr86", "lr87", "lr88", "lr89", "lr90", \
 130  "lr91", "lr92", "lr93", "lr94", "lr95", "lr96", "lr97", "lr98", "lr99", \
 131  "lr100", "lr101", "lr102", "lr103", "lr104", "lr105", "lr106", "lr107", \
 132  "lr108", "lr109", "lr110", "lr111", "lr112", "lr113", "lr114", "lr115", \
 133  "lr116", "lr117", "lr118", "lr119", "lr120", "lr121", "lr122", "lr123", \
 134  "lr124", "lr125", "lr126", "lr127",                                     \
 135   "AI0", "AI1", "AI2", "AI3", "AI4", "AI5", "AI6", "AI7", "AI8", "AI9",  \
 136   "AI10", "AI11", "AI12", "AI13", "AI14", "AI15", "FP",                  \
 137   "bp", "fc", "cr", "q",                                                 \
 138   "vab", "ops", "cps", "cfg", "cha", "chd", "chc", "rbp", "tmc", "tmr",  \
 139   "pc0", "pc1", "pc2", "mmu", "lru", "fpe", "inte", "fps", "exo", "gr1",  \
 140   "alu", "ipc", "ipa", "ipb" }
 141
 142 /*
 143  * Converts an sdb register number to an internal gdb register number.
 144  * Currently under epi, gr96->0...gr127->31...lr0->32...lr127->159, or...
 145  *                      gr64->0...gr95->31, lr0->32...lr127->159.
 146  */
 147 #define SDB_REG_TO_REGNUM(value) \
 148   (((value) >= 96 && (value) <= 127) ? ((value) - 96) : \
 149    ((value) >= 128 && (value) <=  255) ? ((value) - 128 + LR0_REGNUM) : \
 150    (value))
 151
 152 /*
 153  * Provide the processor register numbers of some registers that are
 154  * expected/written in instructions that might change under different
 155  * register sets.  Namely, gcc can compile (-mkernel-registers) so that
 156  * it uses gr64-gr95 in stead of gr96-gr127.
 157  */
 158 #define MSP_HW_REGNUM   125             /* gr125 */
 159 #define RAB_HW_REGNUM   126             /* gr126 */
 160
 161 /* Convert Processor Special register #x to REGISTER_NAMES register # */
 162 #define SR_REGNUM(x) \
 163   ((x) < 15  ? VAB_REGNUM + (x)                                  \
 164    : (x) >= 128 && (x) < 131 ? IPC_REGNUM + (x) - 128            \
 165    : (x) == 131 ? Q_REGNUM                                       \
 166    : (x) == 132 ? ALU_REGNUM                                     \
 167    : (x) >= 133 && (x) < 136 ? BP_REGNUM + (x) - 133             \
 168    : (x) >= 160 && (x) < 163 ? FPE_REGNUM + (x) - 160            \
 169    : (x) == 164 ? EXO_REGNUM                                     \
 170    : (error ("Internal error in SR_REGNUM"), 0))
 171 #define GR96_REGNUM 0
 172
 173 /* Define the return register separately, so it can be overridden for
 174    kernel procedure calling conventions. */
 175 #define RETURN_REGNUM   GR96_REGNUM
 176 #define GR1_REGNUM 200
 177 /* This needs to be the memory stack pointer, not the register stack pointer,
 178    to make call_function work right.  */
 179 #define SP_REGNUM MSP_REGNUM
 180 #define FP_REGNUM 33 /* lr1 */
 181
 182 /* Return register for transparent calling convention (gr122).  */
 183 #define TPC_REGNUM (122 - 96 + GR96_REGNUM)
 184
 185 /* Large Return Pointer (gr123).  */
 186 #define LRP_REGNUM (123 - 96 + GR96_REGNUM)
 187
 188 /* Static link pointer (gr124).  */
 189 #define SLP_REGNUM (124 - 96 + GR96_REGNUM)
 190
 191 /* Memory Stack Pointer (gr125).  */
 192 #define MSP_REGNUM (125 - 96 + GR96_REGNUM)
 193
 194 /* Register allocate bound (gr126).  */
 195 #define RAB_REGNUM (126 - 96 + GR96_REGNUM)
 196
 197 /* Register Free Bound (gr127).  */
 198 #define RFB_REGNUM (127 - 96 + GR96_REGNUM)
 199
 200 /* Register Stack Pointer.  */
 201 #define RSP_REGNUM GR1_REGNUM
 202 #define LR0_REGNUM 32
 203 #define BP_REGNUM 177
 204 #define FC_REGNUM 178
 205 #define CR_REGNUM 179
 206 #define Q_REGNUM 180
 207 #define VAB_REGNUM 181
 208 #define OPS_REGNUM (VAB_REGNUM + 1)
 209 #define CPS_REGNUM (VAB_REGNUM + 2)
 210 #define CFG_REGNUM (VAB_REGNUM + 3)
 211 #define CHA_REGNUM (VAB_REGNUM + 4)
 212 #define CHD_REGNUM (VAB_REGNUM + 5)
 213 #define CHC_REGNUM (VAB_REGNUM + 6)
 214 #define RBP_REGNUM (VAB_REGNUM + 7)
 215 #define TMC_REGNUM (VAB_REGNUM + 8)
 216 #define TMR_REGNUM (VAB_REGNUM + 9)
 217 #define NPC_REGNUM (VAB_REGNUM + 10)  /* pc0 */
 218 #define PC_REGNUM  (VAB_REGNUM + 11)  /* pc1 */
 219 #define PC2_REGNUM (VAB_REGNUM + 12)
 220 #define MMU_REGNUM (VAB_REGNUM + 13)
 221 #define LRU_REGNUM (VAB_REGNUM + 14)
 222 #define FPE_REGNUM (VAB_REGNUM + 15)
 223 #define INTE_REGNUM (VAB_REGNUM + 16)
 224 #define FPS_REGNUM (VAB_REGNUM + 17)
 225 #define EXO_REGNUM (VAB_REGNUM + 18)
 226 /* gr1 is defined above as 200 = VAB_REGNUM + 19 */
 227 #define ALU_REGNUM (VAB_REGNUM + 20)
 228 #define PS_REGNUM  ALU_REGNUM
 229 #define IPC_REGNUM (VAB_REGNUM + 21)
 230 #define IPA_REGNUM (VAB_REGNUM + 22)
 231 #define IPB_REGNUM (VAB_REGNUM + 23)
 232
 233 #endif  /* !defined(REGISTER_NAMES) */
 234
 235 /* Total amount of space needed to store our copies of the machine's
 236    register state, the array `registers'.  */
 237 #define REGISTER_BYTES (NUM_REGS * 4)
 238
 239 /* Index within `registers' of the first byte of the space for
 240    register N.  */
 241 #define REGISTER_BYTE(N)  ((N)*4)
 242
 243 /* Number of bytes of storage in the actual machine representation
 244    for register N.  */
 245
 246 /* All regs are 4 bytes.  */
 247
 248 #define REGISTER_RAW_SIZE(N) (4)
 249
 250 /* Number of bytes of storage in the program's representation
 251    for register N.  */
 252
 253 /* All regs are 4 bytes.  */
 254
 255 #define REGISTER_VIRTUAL_SIZE(N) (4)
 256
 257 /* Largest value REGISTER_RAW_SIZE can have.  */
 258
 259 #define MAX_REGISTER_RAW_SIZE (4)
 260
 261 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 262
 263 #define MAX_REGISTER_VIRTUAL_SIZE (4)
 264
 265 /* Return the GDB type object for the "standard" data type
 266    of data in register N.  */
 267
 268 #define REGISTER_VIRTUAL_TYPE(N) \
 269   (((N) == PC_REGNUM || (N) == LRP_REGNUM || (N) == SLP_REGNUM         \
 270     || (N) == MSP_REGNUM || (N) == RAB_REGNUM || (N) == RFB_REGNUM     \
 271     || (N) == GR1_REGNUM || (N) == FP_REGNUM || (N) == LR0_REGNUM       \
 272     || (N) == NPC_REGNUM || (N) == PC2_REGNUM)                           \
 273    ? lookup_pointer_type (builtin_type_void) : builtin_type_int)
 274 \f
 275 /* Store the address of the place in which to copy the structure the
 276    subroutine will return.  This is called from call_function. */
 277 /* On the a29k the LRP points to the part of the structure beyond the first
 278    16 words.  */
 279 #define STORE_STRUCT_RETURN(ADDR, SP) \
 280   write_register (LRP_REGNUM, (ADDR) + 16 * 4);
 281
 282 /* Should call_function allocate stack space for a struct return?  */
 283 /* On the a29k objects over 16 words require the caller to allocate space.  */
 284 extern use_struct_convention_fn a29k_use_struct_convention;
 285 #define USE_STRUCT_CONVENTION(gcc_p, type) a29k_use_struct_convention (gcc_p, type)
 286
 287 /* Extract from an array REGBUF containing the (raw) register state
 288    a function return value of type TYPE, and copy that, in virtual format,
 289    into VALBUF.  */
 290
 291 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF)              \
 292   {                                                                        \
 293     int reg_length = TYPE_LENGTH (TYPE);                                   \
 294     if (reg_length > 16 * 4)                                               \
 295       {                                                                    \
 296         reg_length = 16 * 4;                                               \
 297         read_memory (*((int *)(REGBUF) + LRP_REGNUM), (VALBUF) + 16 * 4,   \
 298                      TYPE_LENGTH (TYPE) - 16 * 4);                         \
 299       }                                                                    \
 300     memcpy ((VALBUF), ((int *)(REGBUF))+RETURN_REGNUM, reg_length);        \
 301   }
 302
 303 /* Write into appropriate registers a function return value
 304    of type TYPE, given in virtual format.  */
 305
 306 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 307   {                                                                       \
 308     int reg_length = TYPE_LENGTH (TYPE);                                  \
 309     if (reg_length > 16 * 4)                                              \
 310       {                                                                   \
 311         reg_length = 16 * 4;                                              \
 312         write_memory (read_register (LRP_REGNUM),                         \
 313                       (char *)(VALBUF) + 16 * 4,                          \
 314                       TYPE_LENGTH (TYPE) - 16 * 4);                       \
 315       }                                                                   \
 316     write_register_bytes (REGISTER_BYTE (RETURN_REGNUM), (char *)(VALBUF),  \
 317                           TYPE_LENGTH (TYPE));                            \
 318   }
 319 \f
 320 /* The a29k user's guide documents well what the stacks look like.
 321    But what isn't so clear there is how this interracts with the
 322    symbols, or with GDB.
 323    In the following saved_msp, saved memory stack pointer (which functions
 324    as a memory frame pointer), means either
 325    a register containing the memory frame pointer or, in the case of
 326    functions with fixed size memory frames (i.e. those who don't use
 327    alloca()), the result of the calculation msp + msize.
 328
 329    LOC_ARG, LOC_LOCAL - For GCC, these are relative to saved_msp.
 330      For high C, these are relative to msp (making alloca impossible).
 331    LOC_REGISTER, LOC_REGPARM - The register number is the number at the
 332      time the function is running (after the prologue), or in the case
 333      of LOC_REGPARM, may be a register number in the range 160-175.
 334
 335    The compilers do things like store an argument into memory, and then put out
 336    a LOC_ARG for it, or put it into global registers and put out a
 337    LOC_REGPARM.  Thus is it important to execute the first line of
 338    code (i.e. the line of the open brace, i.e. the prologue) of a function
 339    before trying to print arguments or anything.
 340
 341    The following diagram attempts to depict what is going on in memory
 342    (see also the _a29k user's guide_) and also how that interacts with
 343    GDB frames.  We arbitrarily pick fci->frame to point the same place
 344    as the register stack pointer; since we set it ourself in
 345    INIT_EXTRA_FRAME_INFO, and access it only through the FRAME_*
 346    macros, it doesn't really matter exactly how we
 347    do it.  However, note that FRAME_FP is used in two ways in GDB:
 348    (1) as a "magic cookie" which uniquely identifies frames (even over
 349    calls to the inferior), (2) (in PC_IN_CALL_DUMMY [ON_STACK])
 350    as the value of SP_REGNUM before the dummy frame was pushed.  These
 351    two meanings would be incompatible for the a29k if we defined
 352    CALL_DUMMY_LOCATION == ON_STACK (but we don't, so don't worry about it).
 353    Also note that "lr1" below, while called a frame pointer
 354    in the user's guide, has only one function:  To determine whether
 355    registers need to be filled in the function epilogue.
 356
 357    Consider the code:
 358               < call bar>
 359         loc1: . . .
 360         bar:  sub gr1,gr1,rsize_b
 361               . . .
 362               add mfp,msp,0
 363               sub msp,msp,msize_b
 364               . . .
 365               < call foo >
 366         loc2: . . .
 367         foo:  sub gr1,gr1,rsize_f
 368               . . .
 369               add mfp,msp,0
 370               sub msp,msp,msize_f
 371               . . .
 372         loc3: < suppose the inferior stops here >
 373
 374                    memory stack      register stack
 375                    |           |     |____________|
 376                    |           |     |____loc1____|
 377           +------->|___________|     |            |   ^
 378           |        | ^         |     |  locals_b  |   |
 379           |        | |         |     |____________|   |
 380           |        | |         |     |            |   | rsize_b
 381           |        | | msize_b |     | args_to_f  |   |
 382           |        | |         |     |____________|   |
 383           |        | |         |     |____lr1_____|   V
 384           |        | V         |     |____loc2____|<----------------+
 385           |   +--->|___________|<---------mfp     |   ^             |
 386           |   |    | ^         |     |  locals_f  |   |             |
 387           |   |    | | msize_f |     |____________|   |             |
 388           |   |    | |         |     |            |   | rsize_f     |
 389           |   |    | V         |     |   args     |   |             |
 390           |   |    |___________|<msp |____________|   |             |
 391           |   |                      |_____lr1____|   V             |
 392           |   |                      |___garbage__| <- gr1 <----+   |
 393           |   |                                                 |   |
 394           |   |                                                 |   |
 395           |   |                      pc=loc3                    |   |
 396           |   |                                                 |   |
 397           |   |                                                 |   |
 398           |   |            frame cache                          |   |
 399           |   |       |_________________|                       |   |
 400           |   |       |rsize=rsize_b    |                       |   |
 401           |   |       |msize=msize_b    |                       |   |
 402           +---|--------saved_msp        |                       |   |
 403               |       |frame------------------------------------|---+
 404               |       |pc=loc2          |                       |
 405               |       |_________________|                       |
 406               |       |rsize=rsize_f    |                       |
 407               |       |msize=msize_f    |                       |
 408               +--------saved_msp        |                       |
 409                       |frame------------------------------------+
 410                       |pc=loc3          |
 411                       |_________________|
 412
 413    So, is that sufficiently confusing?  Welcome to the 29000.
 414    Notes:
 415    * The frame for foo uses a memory frame pointer but the frame for
 416      bar does not.  In the latter case the saved_msp is
 417      computed by adding msize to the saved_msp of the
 418      next frame.
 419    * msize is in the frame cache only for high C's sake.  */
 420
 421 void read_register_stack ();
 422 long read_register_stack_integer ();
 423 \f
 424 #define EXTRA_FRAME_INFO  \
 425   CORE_ADDR saved_msp;    \
 426   unsigned int rsize;     \
 427   unsigned int msize;     \
 428   unsigned char flags;
 429
 430 /* Bits for flags in EXTRA_FRAME_INFO */
 431 #define TRANSPARENT_FRAME       0x1     /* This is a transparent frame */
 432 #define MFP_USED                0x2     /* A memory frame pointer is used */
 433
 434 /* Because INIT_FRAME_PC gets passed fromleaf, that's where we init
 435    not only ->pc and ->frame, but all the extra stuff, when called from
 436    get_prev_frame_info, that is.  */
 437 #define INIT_EXTRA_FRAME_INFO(fromleaf, fci)  init_extra_frame_info(fci)
 438 void init_extra_frame_info ();
 439
 440 #define INIT_FRAME_PC(fromleaf, fci) init_frame_pc(fromleaf, fci)
 441 void init_frame_pc ();
 442
 443 \f
 444 /* FRAME_CHAIN takes a FRAME
 445    and produces the frame's chain-pointer.
 446
 447    However, if FRAME_CHAIN_VALID returns zero,
 448    it means the given frame is the outermost one and has no caller.  */
 449
 450 /* On the a29k, the nominal address of a frame is the address on the
 451    register stack of the return address (the one next to the incoming
 452    arguments, not down at the bottom so nominal address == stack pointer).
 453
 454    GDB expects "nominal address" to equal contents of FP_REGNUM,
 455    at least when it comes time to create the innermost frame.
 456    However, that doesn't work for us, so when creating the innermost
 457    frame we set ->frame ourselves in INIT_EXTRA_FRAME_INFO.  */
 458
 459 /* These are mostly dummies for the a29k because INIT_FRAME_PC
 460    sets prev->frame instead.  */
 461 /* If rsize is zero, we must be at end of stack (or otherwise hosed).
 462    If we don't check rsize, we loop forever if we see rsize == 0.  */
 463 #define FRAME_CHAIN(thisframe) \
 464   ((thisframe)->rsize == 0 \
 465    ? 0 \
 466    : (thisframe)->frame + (thisframe)->rsize)
 467
 468 /* Determine if the frame has a 'previous' and back-traceable frame. */
 469 #define FRAME_IS_UNCHAINED(frame)       ((frame)->flags & TRANSPARENT_FRAME)
 470
 471 /* Find the previous frame of a transparent routine.
 472  * For now lets not try and trace through a transparent routine (we might
 473  * have to assume that all transparent routines are traps).
 474  */
 475 #define FIND_PREV_UNCHAINED_FRAME(frame)        0
 476
 477 /* Define other aspects of the stack frame.  */
 478
 479 /* A macro that tells us whether the function invocation represented
 480    by FI does not have a frame on the stack associated with it.  If it
 481    does not, FRAMELESS is set to 1, else 0.  */
 482 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 483   (FRAMELESS) = frameless_look_for_prologue(FI)
 484
 485 /* Saved pc (i.e. return address).  */
 486 #define FRAME_SAVED_PC(fraim) \
 487   (read_register_stack_integer ((fraim)->frame + (fraim)->rsize, 4))
 488
 489 /* Local variables (i.e. LOC_LOCAL) are on the memory stack, with their
 490    offsets being relative to the memory stack pointer (high C) or
 491    saved_msp (gcc).  */
 492
 493 #define FRAME_LOCALS_ADDRESS(fi) frame_locals_address (fi)
 494 extern CORE_ADDR frame_locals_address ();
 495
 496 /* Return number of args passed to a frame.
 497    Can return -1, meaning no way to tell.  */
 498 /* We tried going to the effort of finding the tags word and getting
 499    the argcount field from it, to support debugging assembler code.
 500    Problem was, the "argcount" field never did hold the argument
 501    count.  */
 502 #define FRAME_NUM_ARGS(numargs, fi) ((numargs) = -1)
 503
 504 #define FRAME_ARGS_ADDRESS(fi) FRAME_LOCALS_ADDRESS (fi)
 505
 506 /* Return number of bytes at start of arglist that are not really args.  */
 507
 508 #define FRAME_ARGS_SKIP 0
 509
 510 /* Provide our own get_saved_register.  HAVE_REGISTER_WINDOWS is insufficient
 511    because registers get renumbered on the a29k without getting saved.  */
 512
 513 #define GET_SAVED_REGISTER
 514 \f
 515 /* Call function stuff.  */
 516
 517 /* The dummy frame looks like this (see also the general frame picture
 518    above):
 519
 520                                         register stack
 521
 522                                       |                |  frame for function
 523                                       |   locals_sproc |  executing at time
 524                                       |________________|  of call_function.
 525                                       |                |  We must not disturb
 526                                       | args_out_sproc |  it.
 527         memory stack                  |________________|
 528                                       |____lr1_sproc___|<-+
 529        |            |                 |__retaddr_sproc_|  | <-- gr1 (at start)
 530        |____________|<-msp 0 <-----------mfp_dummy_____|  |
 531        |            |  (at start)     |  save regs     |  |
 532        | arg_slop   |                 |  pc0,pc1       |  |
 533        |            |                 |  pc2,lr0 sproc |  |
 534        | (16 words) |                 | gr96-gr124     |  |
 535        |____________|<-msp 1--after   | sr160-sr162    |  |
 536        |            | PUSH_DUMMY_FRAME| sr128-sr135    |  |
 537        | struct ret |                 |________________|  |
 538        | 17+        |                 |                |  |
 539        |____________|<- lrp           | args_out_dummy |  |
 540        | struct ret |                 |  (16 words)    |  |
 541        | 16         |                 |________________|  |
 542        | (16 words) |                 |____lr1_dummy___|--+
 543        |____________|<- msp 2--after  |_retaddr_dummy__|<- gr1 after
 544        |            | struct ret      |                |   PUSH_DUMMY_FRAME
 545        | margs17+   | area allocated  |  locals_inf    |
 546        |            |                 |________________|    called
 547        |____________|<- msp 4--when   |                |    function's
 548        |            |   inf called    | args_out_inf   |    frame (set up
 549        | margs16    |                 |________________|    by called
 550        | (16 words) |                 |_____lr1_inf____|    function).
 551        |____________|<- msp 3--after  |       .        |
 552        |            |   args pushed   |       .        |
 553        |            |                 |       .        |
 554                                       |                |
 555
 556    arg_slop: This area is so that when the call dummy adds 16 words to
 557       the msp, it won't end up larger than mfp_dummy (it is needed in the
 558       case where margs and struct_ret do not add up to at least 16 words).
 559    struct ret:  This area is allocated by GDB if the return value is more
 560       than 16 words.  struct ret_16 is not used on the a29k.
 561    margs:  Pushed by GDB.  The call dummy copies the first 16 words to
 562       args_out_dummy.
 563    retaddr_sproc:  Contains the PC at the time we call the function.
 564       set by PUSH_DUMMY_FRAME and read by POP_FRAME.
 565    retaddr_dummy:  This points to a breakpoint instruction in the dummy.  */
 566 \f
 567 /* Rsize for dummy frame, in bytes.  */
 568
 569 /* Bytes for outgoing args, lr1, and retaddr.  */
 570 #define DUMMY_ARG (2 * 4 + 16 * 4)
 571
 572 /* Number of special registers (sr128-) to save.  */
 573 #define DUMMY_SAVE_SR128 8
 574 /* Number of special registers (sr160-) to save.  */
 575 #define DUMMY_SAVE_SR160 3
 576 /* Number of general (gr96- or gr64-) registers to save.  */
 577 #define DUMMY_SAVE_GREGS 29
 578
 579 #define DUMMY_FRAME_RSIZE \
 580 (4 /* mfp_dummy */        \
 581  + 4 * 4  /* pc0, pc1, pc2, lr0 */  \
 582  + DUMMY_SAVE_GREGS * 4   \
 583  + DUMMY_SAVE_SR160 * 4   \
 584  + DUMMY_SAVE_SR128 * 4   \
 585  + DUMMY_ARG              \
 586  + 4 /* pad to doubleword */ )
 587
 588 /* Push an empty stack frame, to record the current PC, etc.  */
 589
 590 #define PUSH_DUMMY_FRAME push_dummy_frame()
 591 extern void push_dummy_frame ();
 592
 593 /* Discard from the stack the innermost frame,
 594    restoring all saved registers.  */
 595
 596 #define POP_FRAME pop_frame()
 597 extern void pop_frame ();
 598
 599 /* This sequence of words is the instructions
 600    mtsrim cr, 15
 601    loadm 0, 0, lr2, msp     ; load first 16 words of arguments into registers
 602    add msp, msp, 16 * 4     ; point to the remaining arguments
 603  CONST_INSN:
 604    const lr0,inf                ; (replaced by       half of target addr)
 605    consth lr0,inf               ; (replaced by other half of target addr)
 606    calli lr0, lr0
 607    aseq 0x40,gr1,gr1   ; nop
 608  BREAKPT_INSN:
 609    asneq 0x50,gr1,gr1  ; breakpoint     (replaced by local breakpoint insn)
 610    */
 611
 612 #if TARGET_BYTE_ORDER == HOST_BYTE_ORDER
 613 #define BS(const)       const
 614 #else
 615 #define BS(const)       (((const) & 0xff) << 24) |      \
 616                         (((const) & 0xff00) << 8) |     \
 617                         (((const) & 0xff0000) >> 8) |   \
 618                         (((const) & 0xff000000) >> 24)
 619 #endif
 620
 621 /* Position of the "const" and blkt instructions within CALL_DUMMY in bytes. */
 622 #define CONST_INSN (3 * 4)
 623 #define BREAKPT_INSN (7 * 4)
 624 #define CALL_DUMMY {    \
 625                 BS(0x0400870f),\
 626                 BS(0x36008200|(MSP_HW_REGNUM)), \
 627                 BS(0x15000040|(MSP_HW_REGNUM<<8)|(MSP_HW_REGNUM<<16)), \
 628                 BS(0x03ff80ff), \
 629                 BS(0x02ff80ff), \
 630                 BS(0xc8008080), \
 631                 BS(0x70400101), \
 632                 BS(0x72500101)}
 633 #define CALL_DUMMY_LENGTH (8 * 4)
 634
 635 #define CALL_DUMMY_START_OFFSET 0  /* Start execution at beginning of dummy */
 636
 637 /* Helper macro for FIX_CALL_DUMMY.  WORDP is a long * which points to a
 638    word in target byte order; bits 0-7 and 16-23 of *WORDP are replaced with
 639    bits 0-7 and 8-15 of DATA (which is in host byte order).  */
 640
 641 #if TARGET_BYTE_ORDER == BIG_ENDIAN
 642 #define STUFF_I16(WORDP, DATA) \
 643   { \
 644     *((char *)(WORDP) + 3) = ((DATA) & 0xff);\
 645     *((char *)(WORDP) + 1) = (((DATA) >> 8) & 0xff);\
 646   }
 647 #else /* Target is little endian.  */
 648 #define STUFF_I16(WORDP, DATA) \
 649   {
 650     *(char *)(WORDP) = ((DATA) & 0xff);
 651     *((char *)(WORDP) + 2) = (((DATA) >> 8) & 0xff);
 652   }
 653 #endif /* Target is little endian.  */
 654
 655 /* Insert the specified number of args and function address
 656    into a call sequence of the above form stored at DUMMYNAME.  */
 657
 658 /* Currently this stuffs in the address of the function that we are calling.
 659    Since different a29k systems use different breakpoint instructions, it
 660    also stuffs BREAKPOINT in the right place (to avoid having to
 661    duplicate CALL_DUMMY in each tm-*.h file).  */
 662
 663 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)   \
 664   {\
 665     STUFF_I16((char *)dummyname + CONST_INSN, fun);             \
 666     STUFF_I16((char *)dummyname + CONST_INSN + 4, fun >> 16);   \
 667   /* FIXME  memcpy ((char *)(dummyname) + BREAKPT_INSN, break_insn, 4); */ \
 668   }
 669
 670 /* a29k architecture has separate data & instruction memories -- wired to
 671    different pins on the chip -- and can't execute the data memory.
 672    Also, there should be space after text_end;
 673    we won't get a SIGSEGV or scribble on data space.  */
 674
 675 #define CALL_DUMMY_LOCATION AFTER_TEXT_END
 676
 677 /* Because of this, we need (as a kludge) to know the addresses of the
 678    text section.  */
 679
 680 #define NEED_TEXT_START_END 1
 681
 682 /* How to translate register numbers in the .stab's into gdb's internal register
 683    numbers.  We don't translate them, but we warn if an invalid register
 684    number is seen.  Note that FIXME, we use the value "sym" as an implicit
 685    argument in printing the error message.  It happens to be available where
 686    this macro is used.  (This macro definition appeared in a late revision
 687    of gdb-3.91.6 and is not well tested.  Also, it should be a "complaint".) */
 688
 689 #define STAB_REG_TO_REGNUM(num) \
 690         (((num) > LR0_REGNUM + 127) \
 691            ? fprintf(stderr,    \
 692                 "Invalid register number %d in symbol table entry for %s\n", \
 693                  (num), SYMBOL_SOURCE_NAME (sym)), (num)        \
 694            : (num))
 695
 696 extern enum a29k_processor_types {
 697   a29k_unknown,
 698
 699   /* Bit 0x400 of the CPS does *not* identify freeze mode, i.e. 29000,
 700      29030, etc.  */
 701   a29k_no_freeze_mode,
 702
 703   /* Bit 0x400 of the CPS does identify freeze mode, i.e. 29050.  */
 704   a29k_freeze_mode
 705 } processor_type;
 706
 707 /* We need three arguments for a general frame specification for the
 708    "frame" or "info frame" command.  */
 709
 710 #define SETUP_ARBITRARY_FRAME(argc, argv) setup_arbitrary_frame (argc, argv)
 711 extern struct frame_info *setup_arbitrary_frame PARAMS ((int, CORE_ADDR *));