gdb/tm-29k.h

   1 /* Parameters for target machine of AMD 29000, for GDB, the GNU debugger.
   2    Copyright 1990, 1991, 1993 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., 675 Mass Ave, Cambridge, MA 02139, 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 29k machines/systems, the
  26    machine/system-specific parts should be removed from this file (a
  27    la tm-68k.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) (read_register (LR0_REGNUM))
  56
  57 /* I'm not sure about the exact value of this, but based on looking
  58    at the stack pointer when we get to main this seems to be right.
  59
  60    This is the register stack; We call it "CONTROL" in GDB for consistency
  61    with Pyramid.  */
  62 #define CONTROL_END_ADDR 0x80200000
  63
  64 /* Memory stack.  This is for the default register stack size, which is
  65    only 0x800 bytes.  Perhaps we should let the user specify stack sizes
  66    (and tell EBMON with the "ZS" command).  */
  67 #define STACK_END_ADDR 0x801ff800
  68
  69 /* Stack grows downward.  */
  70
  71 #define INNER_THAN <
  72
  73 /* Stack must be aligned on 32-bit word boundaries.  */
  74 #define STACK_ALIGN(ADDR) (((ADDR) + 3) & ~3)
  75
  76 /* Sequence of bytes for breakpoint instruction.  */
  77 /* ASNEQ 0x50, gr1, gr1
  78    The trap number 0x50 is chosen arbitrarily.
  79    We let the command line (or previously included files) override this
  80    setting.  */
  81 #ifndef BREAKPOINT
  82 #if TARGET_BYTE_ORDER == BIG_ENDIAN
  83 #define BREAKPOINT {0x72, 0x50, 0x01, 0x01}
  84 #else /* Target is little-endian.  */
  85 #define BREAKPOINT {0x01, 0x01, 0x50, 0x72}
  86 #endif /* Target is little-endian.  */
  87 #endif /* BREAKPOINT */
  88
  89 /* Amount PC must be decremented by after a breakpoint.
  90    This is often the number of bytes in BREAKPOINT
  91    but not always.  */
  92
  93 #define DECR_PC_AFTER_BREAK 0
  94
  95 /* Nonzero if instruction at PC is a return instruction.
  96    On the 29k, this is a "jmpi l0" instruction.  */
  97
  98 #define ABOUT_TO_RETURN(pc) \
  99   ((read_memory_integer (pc, 4) & 0xff0000ff) == 0xc0000080)
 100
 101 /* Return 1 if P points to an invalid floating point value.  */
 102
 103 #define INVALID_FLOAT(p, len) 0   /* Just a first guess; not checked */
 104
 105 /* Say how long (ordinary) registers are.  */
 106
 107 #define REGISTER_TYPE long
 108
 109 /* Allow the register declarations here to be overridden for remote
 110    kernel debugging.  */
 111 #if !defined (REGISTER_NAMES)
 112
 113 /* Number of machine registers */
 114
 115 #define NUM_REGS 205
 116
 117 /* Initializer for an array of names of registers.
 118    There should be NUM_REGS strings in this initializer.
 119
 120    FIXME, add floating point registers and support here.
 121
 122    Also note that this list does not attempt to deal with kernel
 123    debugging (in which the first 32 registers are gr64-gr95).  */
 124
 125 #define REGISTER_NAMES \
 126 {"gr96", "gr97", "gr98", "gr99", "gr100", "gr101", "gr102", "gr103", "gr104", \
 127  "gr105", "gr106", "gr107", "gr108", "gr109", "gr110", "gr111", "gr112", \
 128  "gr113", "gr114", "gr115", "gr116", "gr117", "gr118", "gr119", "gr120", \
 129  "gr121", "gr122", "gr123", "gr124", "gr125", "gr126", "gr127",          \
 130  "lr0", "lr1", "lr2", "lr3", "lr4", "lr5", "lr6", "lr7", "lr8", "lr9",   \
 131  "lr10", "lr11", "lr12", "lr13", "lr14", "lr15", "lr16", "lr17", "lr18", \
 132  "lr19", "lr20", "lr21", "lr22", "lr23", "lr24", "lr25", "lr26", "lr27", \
 133  "lr28", "lr29", "lr30", "lr31", "lr32", "lr33", "lr34", "lr35", "lr36", \
 134  "lr37", "lr38", "lr39", "lr40", "lr41", "lr42", "lr43", "lr44", "lr45", \
 135  "lr46", "lr47", "lr48", "lr49", "lr50", "lr51", "lr52", "lr53", "lr54", \
 136  "lr55", "lr56", "lr57", "lr58", "lr59", "lr60", "lr61", "lr62", "lr63", \
 137  "lr64", "lr65", "lr66", "lr67", "lr68", "lr69", "lr70", "lr71", "lr72", \
 138  "lr73", "lr74", "lr75", "lr76", "lr77", "lr78", "lr79", "lr80", "lr81", \
 139  "lr82", "lr83", "lr84", "lr85", "lr86", "lr87", "lr88", "lr89", "lr90", \
 140  "lr91", "lr92", "lr93", "lr94", "lr95", "lr96", "lr97", "lr98", "lr99", \
 141  "lr100", "lr101", "lr102", "lr103", "lr104", "lr105", "lr106", "lr107", \
 142  "lr108", "lr109", "lr110", "lr111", "lr112", "lr113", "lr114", "lr115", \
 143  "lr116", "lr117", "lr118", "lr119", "lr120", "lr121", "lr122", "lr123", \
 144  "lr124", "lr125", "lr126", "lr127",                                     \
 145   "AI0", "AI1", "AI2", "AI3", "AI4", "AI5", "AI6", "AI7", "AI8", "AI9",  \
 146   "AI10", "AI11", "AI12", "AI13", "AI14", "AI15", "FP",                  \
 147   "bp", "fc", "cr", "q",                                                 \
 148   "vab", "ops", "cps", "cfg", "cha", "chd", "chc", "rbp", "tmc", "tmr",  \
 149   "pc0", "pc1", "pc2", "mmu", "lru", "fpe", "inte", "fps", "exo", "gr1",  \
 150   "alu", "ipc", "ipa", "ipb" }
 151
 152 /*
 153  * Converts an sdb register number to an internal gdb register number.
 154  * Currently under epi, gr96->0...gr127->31...lr0->32...lr127->159, or...
 155  *                      gr64->0...gr95->31, lr0->32...lr127->159.
 156  */
 157 #define SDB_REG_TO_REGNUM(value) \
 158   (((value) >= 96 && (value) <= 127) ? ((value) - 96) : \
 159    ((value) >= 128 && (value) <=  255) ? ((value) - 128 + LR0_REGNUM) : \
 160    (value))
 161
 162 /*
 163  * Provide the processor register numbers of some registers that are
 164  * expected/written in instructions that might change under different
 165  * register sets.  Namely, gcc can compile (-mkernel-registers) so that
 166  * it uses gr64-gr95 in stead of gr96-gr127.
 167  */
 168 #define MSP_HW_REGNUM   125             /* gr125 */
 169 #define RAB_HW_REGNUM   126             /* gr126 */
 170
 171 /* Convert Processor Special register #x to REGISTER_NAMES register # */
 172 #define SR_REGNUM(x) \
 173   ((x) < 15  ? VAB_REGNUM + (x)                                  \
 174    : (x) >= 128 && (x) < 131 ? IPC_REGNUM + (x) - 128            \
 175    : (x) == 131 ? Q_REGNUM                                       \
 176    : (x) == 132 ? ALU_REGNUM                                     \
 177    : (x) >= 133 && (x) < 136 ? BP_REGNUM + (x) - 133             \
 178    : (x) >= 160 && (x) < 163 ? FPE_REGNUM + (x) - 160            \
 179    : (x) == 164 ? EXO_REGNUM                                     \
 180    : (error ("Internal error in SR_REGNUM"), 0))
 181 #define GR96_REGNUM 0
 182 /* Define the return register separately, so it can be overridden for
 183    kernel procedure calling conventions. */
 184 #define RETURN_REGNUM   GR96_REGNUM
 185 #define GR1_REGNUM 200
 186 /* This needs to be the memory stack pointer, not the register stack pointer,
 187    to make call_function work right.  */
 188 #define SP_REGNUM MSP_REGNUM
 189 #define FP_REGNUM 33 /* lr1 */
 190 /* Large Return Pointer (gr123).  */
 191 #define LRP_REGNUM (123 - 96 + GR96_REGNUM)
 192 /* Static link pointer (gr124).  */
 193 #define SLP_REGNUM (124 - 96 + GR96_REGNUM)
 194 /* Memory Stack Pointer (gr125).  */
 195 #define MSP_REGNUM (125 - 96 + GR96_REGNUM)
 196 /* Register allocate bound (gr126).  */
 197 #define RAB_REGNUM (126 - 96 + GR96_REGNUM)
 198 /* Register Free Bound (gr127).  */
 199 #define RFB_REGNUM (127 - 96 + GR96_REGNUM)
 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 /* Nonzero if register N requires conversion
 266    from raw format to virtual format.  */
 267
 268 #define REGISTER_CONVERTIBLE(N) (0)
 269
 270 /* Convert data from raw format for register REGNUM
 271    to virtual format for register REGNUM.  */
 272
 273 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) \
 274 { bcopy ((FROM), (TO), 4); }
 275
 276 /* Convert data from virtual format for register REGNUM
 277    to raw format for register REGNUM.  */
 278
 279 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
 280 { bcopy ((FROM), (TO), 4); }
 281
 282 /* Return the GDB type object for the "standard" data type
 283    of data in register N.  */
 284
 285 #define REGISTER_VIRTUAL_TYPE(N) \
 286   (((N) == PC_REGNUM || (N) == LRP_REGNUM || (N) == SLP_REGNUM         \
 287     || (N) == MSP_REGNUM || (N) == RAB_REGNUM || (N) == RFB_REGNUM     \
 288     || (N) == GR1_REGNUM || (N) == FP_REGNUM || (N) == LR0_REGNUM       \
 289     || (N) == NPC_REGNUM || (N) == PC2_REGNUM)                           \
 290    ? lookup_pointer_type (builtin_type_void) : builtin_type_int)
 291 \f
 292 /* Store the address of the place in which to copy the structure the
 293    subroutine will return.  This is called from call_function. */
 294 /* On the 29k the LRP points to the part of the structure beyond the first
 295    16 words.  */
 296 #define STORE_STRUCT_RETURN(ADDR, SP) \
 297   write_register (LRP_REGNUM, (ADDR) + 16 * 4);
 298
 299 /* Should call_function allocate stack space for a struct return?  */
 300 /* On the 29k objects over 16 words require the caller to allocate space.  */
 301 #define USE_STRUCT_CONVENTION(gcc_p, type) (TYPE_LENGTH (type) > 16 * 4)
 302
 303 /* Extract from an array REGBUF containing the (raw) register state
 304    a function return value of type TYPE, and copy that, in virtual format,
 305    into VALBUF.  */
 306
 307 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF)              \
 308   {                                                                        \
 309     int reg_length = TYPE_LENGTH (TYPE);                                   \
 310     if (reg_length > 16 * 4)                                               \
 311       {                                                                    \
 312         reg_length = 16 * 4;                                               \
 313         read_memory (*((int *)(REGBUF) + LRP_REGNUM), (VALBUF) + 16 * 4,   \
 314                      TYPE_LENGTH (TYPE) - 16 * 4);                         \
 315       }                                                                    \
 316     bcopy (((int *)(REGBUF))+RETURN_REGNUM, (VALBUF), reg_length);         \
 317   }
 318
 319 /* Write into appropriate registers a function return value
 320    of type TYPE, given in virtual format.  */
 321
 322 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 323   {                                                                       \
 324     int reg_length = TYPE_LENGTH (TYPE);                                  \
 325     if (reg_length > 16 * 4)                                              \
 326       {                                                                   \
 327         reg_length = 16 * 4;                                              \
 328         write_memory (read_register (LRP_REGNUM),                         \
 329                       (char *)(VALBUF) + 16 * 4,                          \
 330                       TYPE_LENGTH (TYPE) - 16 * 4);                       \
 331       }                                                                   \
 332     write_register_bytes (REGISTER_BYTE (RETURN_REGNUM), (char *)(VALBUF),  \
 333                           TYPE_LENGTH (TYPE));                            \
 334   }
 335 \f
 336 /* The am29k user's guide documents well what the stacks look like.
 337    But what isn't so clear there is how this interracts with the
 338    symbols, or with GDB.
 339    In the following saved_msp, saved memory stack pointer (which functions
 340    as a memory frame pointer), means either
 341    a register containing the memory frame pointer or, in the case of
 342    functions with fixed size memory frames (i.e. those who don't use
 343    alloca()), the result of the calculation msp + msize.
 344
 345    LOC_ARG, LOC_LOCAL - For GCC, these are relative to saved_msp.
 346      For high C, these are relative to msp (making alloca impossible).
 347    LOC_REGISTER, LOC_REGPARM - The register number is the number at the
 348      time the function is running (after the prologue), or in the case
 349      of LOC_REGPARM, may be a register number in the range 160-175.
 350
 351    The compilers do things like store an argument into memory, and then put out
 352    a LOC_ARG for it, or put it into global registers and put out a
 353    LOC_REGPARM.  Thus is it important to execute the first line of
 354    code (i.e. the line of the open brace, i.e. the prologue) of a function
 355    before trying to print arguments or anything.
 356
 357    The following diagram attempts to depict what is going on in memory
 358    (see also the _am29k user's guide_) and also how that interacts with
 359    GDB frames.  We arbitrarily pick fci->frame to point the same place
 360    as the register stack pointer; since we set it ourself in
 361    INIT_EXTRA_FRAME_INFO, and access it only through the FRAME_*
 362    macros, it doesn't really matter exactly how we
 363    do it.  However, note that FRAME_FP is used in two ways in GDB:
 364    (1) as a "magic cookie" which uniquely identifies frames (even over
 365    calls to the inferior), (2) (in PC_IN_CALL_DUMMY [ON_STACK])
 366    as the value of SP_REGNUM before the dummy frame was pushed.  These
 367    two meanings would be incompatible for the 29k if we defined
 368    CALL_DUMMY_LOCATION == ON_STACK (but we don't, so don't worry about it).
 369    Also note that "lr1" below, while called a frame pointer
 370    in the user's guide, has only one function:  To determine whether
 371    registers need to be filled in the function epilogue.
 372
 373    Consider the code:
 374               < call bar>
 375         loc1: . . .
 376         bar:  sub gr1,gr1,rsize_b
 377               . . .
 378               add mfp,msp,0
 379               sub msp,msp,msize_b
 380               . . .
 381               < call foo >
 382         loc2: . . .
 383         foo:  sub gr1,gr1,rsize_f
 384               . . .
 385               add mfp,msp,0
 386               sub msp,msp,msize_f
 387               . . .
 388         loc3: < suppose the inferior stops here >
 389
 390                    memory stack      register stack
 391                    |           |     |____________|
 392                    |           |     |____loc1____|
 393           +------->|___________|     |            |   ^
 394           |        | ^         |     |  locals_b  |   |
 395           |        | |         |     |____________|   |
 396           |        | |         |     |            |   | rsize_b
 397           |        | | msize_b |     | args_to_f  |   |
 398           |        | |         |     |____________|   |
 399           |        | |         |     |____lr1_____|   V
 400           |        | V         |     |____loc2____|<----------------+
 401           |   +--->|___________|<---------mfp     |   ^             |
 402           |   |    | ^         |     |  locals_f  |   |             |
 403           |   |    | | msize_f |     |____________|   |             |
 404           |   |    | |         |     |            |   | rsize_f     |
 405           |   |    | V         |     |   args     |   |             |
 406           |   |    |___________|<msp |____________|   |             |
 407           |   |                      |_____lr1____|   V             |
 408           |   |                      |___garbage__| <- gr1 <----+   |
 409           |   |                                                 |   |
 410           |   |                                                 |   |
 411           |   |                      pc=loc3                    |   |
 412           |   |                                                 |   |
 413           |   |                                                 |   |
 414           |   |            frame cache                          |   |
 415           |   |       |_________________|                       |   |
 416           |   |       |rsize=rsize_b    |                       |   |
 417           |   |       |msize=msize_b    |                       |   |
 418           +---|--------saved_msp        |                       |   |
 419               |       |frame------------------------------------|---+
 420               |       |pc=loc2          |                       |
 421               |       |_________________|                       |
 422               |       |rsize=rsize_f    |                       |
 423               |       |msize=msize_f    |                       |
 424               +--------saved_msp        |                       |
 425                       |frame------------------------------------+
 426                       |pc=loc3          |
 427                       |_________________|
 428
 429    So, is that sufficiently confusing?  Welcome to the 29000.
 430    Notes:
 431    * The frame for foo uses a memory frame pointer but the frame for
 432      bar does not.  In the latter case the saved_msp is
 433      computed by adding msize to the saved_msp of the
 434      next frame.
 435    * msize is in the frame cache only for high C's sake.  */
 436
 437 void read_register_stack ();
 438 long read_register_stack_integer ();
 439 \f
 440 #define EXTRA_FRAME_INFO  \
 441   CORE_ADDR saved_msp;    \
 442   unsigned int rsize;     \
 443   unsigned int msize;     \
 444   unsigned char flags;
 445
 446 /* Bits for flags in EXTRA_FRAME_INFO */
 447 #define TRANSPARENT     0x1             /* This is a transparent frame */
 448 #define MFP_USED        0x2             /* A memory frame pointer is used */
 449
 450 /* Because INIT_FRAME_PC gets passed fromleaf, that's where we init
 451    not only ->pc and ->frame, but all the extra stuff, when called from
 452    get_prev_frame_info, that is.  */
 453 #define INIT_EXTRA_FRAME_INFO(fromleaf, fci)  init_extra_frame_info(fci)
 454 void init_extra_frame_info ();
 455
 456 #define INIT_FRAME_PC(fromleaf, fci) init_frame_pc(fromleaf, fci)
 457 void init_frame_pc ();
 458
 459 \f
 460 /* FRAME_CHAIN takes a FRAME
 461    and produces the frame's chain-pointer.
 462
 463    However, if FRAME_CHAIN_VALID returns zero,
 464    it means the given frame is the outermost one and has no caller.  */
 465
 466 /* On the 29k, the nominal address of a frame is the address on the
 467    register stack of the return address (the one next to the incoming
 468    arguments, not down at the bottom so nominal address == stack pointer).
 469
 470    GDB expects "nominal address" to equal contents of FP_REGNUM,
 471    at least when it comes time to create the innermost frame.
 472    However, that doesn't work for us, so when creating the innermost
 473    frame we set ->frame ourselves in INIT_EXTRA_FRAME_INFO.  */
 474
 475 /* These are mostly dummies for the 29k because INIT_FRAME_PC
 476    sets prev->frame instead.  */
 477 #define FRAME_CHAIN(thisframe) ((thisframe)->frame + (thisframe)->rsize)
 478
 479 /* Determine if the frame has a 'previous' and back-traceable frame. */
 480 #define FRAME_IS_UNCHAINED(frame)       ((frame)->flags & TRANSPARENT)
 481
 482 /* Find the previous frame of a transparent routine.
 483  * For now lets not try and trace through a transparent routine (we might
 484  * have to assume that all transparent routines are traps).
 485  */
 486 #define FIND_PREV_UNCHAINED_FRAME(frame)        0
 487
 488 /* Define other aspects of the stack frame.  */
 489
 490 /* A macro that tells us whether the function invocation represented
 491    by FI does not have a frame on the stack associated with it.  If it
 492    does not, FRAMELESS is set to 1, else 0.  */
 493 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 494   (FRAMELESS) = frameless_look_for_prologue(FI)
 495
 496 /* Saved pc (i.e. return address).  */
 497 #define FRAME_SAVED_PC(fraim) \
 498   (read_register_stack_integer ((fraim)->frame + (fraim)->rsize, 4))
 499
 500 /* Local variables (i.e. LOC_LOCAL) are on the memory stack, with their
 501    offsets being relative to the memory stack pointer (high C) or
 502    saved_msp (gcc).  */
 503
 504 #define FRAME_LOCALS_ADDRESS(fi) frame_locals_address (fi)
 505 extern CORE_ADDR frame_locals_address ();
 506
 507 /* Return number of args passed to a frame.
 508    Can return -1, meaning no way to tell.  */
 509 /* While we could go the effort of finding the tags word and getting
 510    the argcount field from it,
 511    (1) It only counts arguments in registers, i.e. the first 16 words
 512        of arguments
 513    (2) It gives the number of arguments the function was declared with
 514        not how many it was called with (or some variation, like all 16
 515        words for varadic functions).  This makes argcount pretty much
 516        redundant with -g info, even for varadic functions.
 517    So don't bother.  */
 518 #define FRAME_NUM_ARGS(numargs, fi) ((numargs) = -1)
 519
 520 #define FRAME_ARGS_ADDRESS(fi) FRAME_LOCALS_ADDRESS (fi)
 521
 522 /* Return number of bytes at start of arglist that are not really args.  */
 523
 524 #define FRAME_ARGS_SKIP 0
 525
 526 /* Provide our own get_saved_register.  HAVE_REGISTER_WINDOWS is insufficient
 527    because registers get renumbered on the 29k without getting saved.  */
 528
 529 #define GET_SAVED_REGISTER
 530 \f
 531 /* Call function stuff.  */
 532
 533 /* The dummy frame looks like this (see also the general frame picture
 534    above):
 535
 536                                         register stack
 537
 538                                       |                |  frame for function
 539                                       |   locals_sproc |  executing at time
 540                                       |________________|  of call_function.
 541                                       |                |  We must not disturb
 542                                       | args_out_sproc |  it.
 543         memory stack                  |________________|
 544                                       |____lr1_sproc___|<-+
 545        |            |                 |__retaddr_sproc_|  | <-- gr1 (at start)
 546        |____________|<-msp 0 <-----------mfp_dummy_____|  |
 547        |            |  (at start)     |  save regs     |  |
 548        | arg_slop   |                 |  pc0,pc1       |  |
 549        | (16 words) |                 | gr96-gr124     |  |
 550        |____________|<-msp 1--after   | sr160-sr162    |  |
 551        |            | PUSH_DUMMY_FRAME| sr128-sr135    |  |
 552        | struct ret |                 |________________|  |
 553        | 17+        |                 |                |  |
 554        |____________|<- lrp           | args_out_dummy |  |
 555        | struct ret |                 |  (16 words)    |  |
 556        | 16         |                 |________________|  |
 557        | (16 words) |                 |____lr1_dummy___|--+
 558        |____________|<- msp 2--after  |_retaddr_dummy__|<- gr1 after
 559        |            | struct ret      |                |   PUSH_DUMMY_FRAME
 560        | margs17+   | area allocated  |  locals_inf    |
 561        |            |                 |________________|    called
 562        |____________|<- msp 4--when   |                |    function's
 563        |            |   inf called    | args_out_inf   |    frame (set up
 564        | margs16    |                 |________________|    by called
 565        | (16 words) |                 |_____lr1_inf____|    function).
 566        |____________|<- msp 3--after  |       .        |
 567        |            |   args pushed   |       .        |
 568        |            |                 |       .        |
 569                                       |                |
 570
 571    arg_slop: This area is so that when the call dummy adds 16 words to
 572       the msp, it won't end up larger than mfp_dummy (it is needed in the
 573       case where margs and struct_ret do not add up to at least 16 words).
 574    struct ret:  This area is allocated by GDB if the return value is more
 575       than 16 words.  struct ret_16 is not used on the 29k.
 576    margs:  Pushed by GDB.  The call dummy copies the first 16 words to
 577       args_out_dummy.
 578    retaddr_sproc:  Contains the PC at the time we call the function.
 579       set by PUSH_DUMMY_FRAME and read by POP_FRAME.
 580    retaddr_dummy:  This points to a breakpoint instruction in the dummy.  */
 581 \f
 582 /* Rsize for dummy frame, in bytes.  */
 583
 584 /* Bytes for outgoing args, lr1, and retaddr.  */
 585 #define DUMMY_ARG (2 * 4 + 16 * 4)
 586
 587 /* Number of special registers (sr128-) to save.  */
 588 #define DUMMY_SAVE_SR128 8
 589 /* Number of special registers (sr160-) to save.  */
 590 #define DUMMY_SAVE_SR160 3
 591 /* Number of general (gr96- or gr64-) registers to save.  */
 592 #define DUMMY_SAVE_GREGS 29
 593
 594 #define DUMMY_FRAME_RSIZE \
 595 (4 /* mfp_dummy */        \
 596  + 2 * 4  /* pc0, pc1 */  \
 597  + DUMMY_SAVE_GREGS * 4   \
 598  + DUMMY_SAVE_SR160 * 4   \
 599  + DUMMY_SAVE_SR128 * 4   \
 600  + DUMMY_ARG              \
 601  + 4 /* pad to doubleword */ )
 602
 603 /* Push an empty stack frame, to record the current PC, etc.  */
 604
 605 #define PUSH_DUMMY_FRAME push_dummy_frame()
 606 extern void push_dummy_frame ();
 607
 608 /* Discard from the stack the innermost frame,
 609    restoring all saved registers.  */
 610
 611 #define POP_FRAME pop_frame()
 612 extern void pop_frame ();
 613
 614 /* This sequence of words is the instructions
 615    mtsrim cr, 15
 616    loadm 0, 0, lr2, msp     ; load first 16 words of arguments into registers
 617    add msp, msp, 16 * 4     ; point to the remaining arguments
 618  CONST_INSN:
 619    const lr0,inf                ; (replaced by       half of target addr)
 620    consth lr0,inf               ; (replaced by other half of target addr)
 621    calli lr0, lr0
 622    aseq 0x40,gr1,gr1   ; nop
 623  BREAKPT_INSN:
 624    asneq 0x50,gr1,gr1  ; breakpoint     (replaced by local breakpoint insn)
 625    */
 626
 627 #if TARGET_BYTE_ORDER == HOST_BYTE_ORDER
 628 #define BS(const)       const
 629 #else
 630 #define BS(const)       (((const) & 0xff) << 24) |      \
 631                         (((const) & 0xff00) << 8) |     \
 632                         (((const) & 0xff0000) >> 8) |   \
 633                         (((const) & 0xff000000) >> 24)
 634 #endif
 635
 636 /* Position of the "const" and blkt instructions within CALL_DUMMY in bytes. */
 637 #define CONST_INSN (3 * 4)
 638 #define BREAKPT_INSN (7 * 4)
 639 #define CALL_DUMMY {    \
 640                 BS(0x0400870f),\
 641                 BS(0x36008200|(MSP_HW_REGNUM)), \
 642                 BS(0x15000040|(MSP_HW_REGNUM<<8)|(MSP_HW_REGNUM<<16)), \
 643                 BS(0x03ff80ff), \
 644                 BS(0x02ff80ff), \
 645                 BS(0xc8008080), \
 646                 BS(0x70400101), \
 647                 BS(0x72500101)}
 648 #define CALL_DUMMY_LENGTH (8 * 4)
 649
 650 #define CALL_DUMMY_START_OFFSET 0  /* Start execution at beginning of dummy */
 651
 652 /* Helper macro for FIX_CALL_DUMMY.  WORDP is a long * which points to a
 653    word in target byte order; bits 0-7 and 16-23 of *WORDP are replaced with
 654    bits 0-7 and 8-15 of DATA (which is in host byte order).  */
 655
 656 #if TARGET_BYTE_ORDER == BIG_ENDIAN
 657 #define STUFF_I16(WORDP, DATA) \
 658   { \
 659     *((char *)(WORDP) + 3) = ((DATA) & 0xff);\
 660     *((char *)(WORDP) + 1) = (((DATA) >> 8) & 0xff);\
 661   }
 662 #else /* Target is little endian.  */
 663 #define STUFF_I16(WORDP, DATA) \
 664   {
 665     *(char *)(WORDP) = ((DATA) & 0xff);
 666     *((char *)(WORDP) + 2) = (((DATA) >> 8) & 0xff);
 667   }
 668 #endif /* Target is little endian.  */
 669
 670 /* Insert the specified number of args and function address
 671    into a call sequence of the above form stored at DUMMYNAME.  */
 672
 673 /* Currently this stuffs in the address of the function that we are calling.
 674    Since different 29k systems use different breakpoint instructions, it
 675    also stuffs BREAKPOINT in the right place (to avoid having to
 676    duplicate CALL_DUMMY in each tm-*.h file).  */
 677
 678 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)   \
 679   {\
 680     STUFF_I16((char *)dummyname + CONST_INSN, fun);             \
 681     STUFF_I16((char *)dummyname + CONST_INSN + 4, fun >> 16);   \
 682   /* FIXME  memcpy ((char *)(dummyname) + BREAKPT_INSN, break_insn, 4); */ \
 683   }
 684
 685 /* 29k architecture has separate data & instruction memories -- wired to
 686    different pins on the chip -- and can't execute the data memory.
 687    Also, there should be space after text_end;
 688    we won't get a SIGSEGV or scribble on data space.  */
 689
 690 #define CALL_DUMMY_LOCATION AFTER_TEXT_END
 691
 692 /* Because of this, we need (as a kludge) to know the addresses of the
 693    text section.  */
 694
 695 #define NEED_TEXT_START_END
 696
 697 /* How to translate register numbers in the .stab's into gdb's internal register
 698    numbers.  We don't translate them, but we warn if an invalid register
 699    number is seen.  Note that FIXME, we use the value "sym" as an implicit
 700    argument in printing the error message.  It happens to be available where
 701    this macro is used.  (This macro definition appeared in a late revision
 702    of gdb-3.91.6 and is not well tested.  Also, it should be a "complaint".) */
 703
 704 #define STAB_REG_TO_REGNUM(num) \
 705         (((num) > LR0_REGNUM + 127) \
 706            ? fprintf(stderr,    \
 707                 "Invalid register number %d in symbol table entry for %s\n", \
 708                  (num), SYMBOL_SOURCE_NAME (sym)), (num)        \
 709            : (num))