gdb/config/pa/tm-hppa.h

   1 /* Parameters for execution on any Hewlett-Packard PA-RISC machine.
   2    Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
   3    1998, 1999, 2000 Free Software Foundation, Inc.
   4
   5    Contributed by the Center for Software Science at the
   6    University of Utah (pa-gdb-bugs@cs.utah.edu).
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 59 Temple Place - Suite 330,
  23    Boston, MA 02111-1307, USA.  */
  24
  25 #include "regcache.h"
  26
  27 #define GDB_MULTI_ARCH 0
  28
  29 /* Forward declarations of some types we use in prototypes */
  30
  31 struct frame_info;
  32 struct frame_saved_regs;
  33 struct value;
  34 struct type;
  35 struct inferior_status;
  36
  37 /* By default assume we don't have to worry about software floating point.  */
  38 #ifndef SOFT_FLOAT
  39 #define SOFT_FLOAT 0
  40 #endif
  41
  42 /* Get at various relevent fields of an instruction word. */
  43
  44 #define MASK_5 0x1f
  45 #define MASK_11 0x7ff
  46 #define MASK_14 0x3fff
  47 #define MASK_21 0x1fffff
  48
  49 /* This macro gets bit fields using HP's numbering (MSB = 0) */
  50 #ifndef GET_FIELD
  51 #define GET_FIELD(X, FROM, TO) \
  52   ((X) >> (31 - (TO)) & ((1 << ((TO) - (FROM) + 1)) - 1))
  53 #endif
  54
  55 /* On the PA, any pass-by-value structure > 8 bytes is actually
  56    passed via a pointer regardless of its type or the compiler
  57    used.  */
  58
  59 #define REG_STRUCT_HAS_ADDR(gcc_p,type) \
  60   (TYPE_LENGTH (type) > 8)
  61
  62 /* Offset from address of function to start of its code.
  63    Zero on most machines.  */
  64
  65 #define FUNCTION_START_OFFSET 0
  66
  67 /* Advance PC across any function entry prologue instructions
  68    to reach some "real" code.  */
  69
  70 extern CORE_ADDR hppa_skip_prologue (CORE_ADDR);
  71 #define SKIP_PROLOGUE(pc) (hppa_skip_prologue (pc))
  72
  73 /* If PC is in some function-call trampoline code, return the PC
  74    where the function itself actually starts.  If not, return NULL.  */
  75
  76 #define SKIP_TRAMPOLINE_CODE(pc) skip_trampoline_code (pc, NULL)
  77 extern CORE_ADDR skip_trampoline_code (CORE_ADDR, char *);
  78
  79 /* Return non-zero if we are in an appropriate trampoline. */
  80
  81 #define IN_SOLIB_CALL_TRAMPOLINE(pc, name) \
  82    in_solib_call_trampoline (pc, name)
  83 extern int in_solib_call_trampoline (CORE_ADDR, char *);
  84
  85 #define IN_SOLIB_RETURN_TRAMPOLINE(pc, name) \
  86   in_solib_return_trampoline (pc, name)
  87 extern int in_solib_return_trampoline (CORE_ADDR, char *);
  88
  89 /* Immediately after a function call, return the saved pc.
  90    Can't go through the frames for this because on some machines
  91    the new frame is not set up until the new function executes
  92    some instructions.  */
  93
  94 #undef  SAVED_PC_AFTER_CALL
  95 #define SAVED_PC_AFTER_CALL(frame) saved_pc_after_call (frame)
  96 extern CORE_ADDR saved_pc_after_call (struct frame_info *);
  97
  98 /* Stack grows upward */
  99 #define INNER_THAN(lhs,rhs) ((lhs) > (rhs))
 100
 101 /* elz: adjust the quantity to the next highest value which is 64-bit aligned.
 102    This is used in valops.c, when the sp is adjusted.
 103    On hppa the sp must always be kept 64-bit aligned */
 104
 105 #define STACK_ALIGN(arg) ( ((arg)%8) ? (((arg)+7)&-8) : (arg))
 106 #define EXTRA_STACK_ALIGNMENT_NEEDED 0
 107
 108 /* Sequence of bytes for breakpoint instruction.  */
 109
 110 #define BREAKPOINT {0x00, 0x01, 0x00, 0x04}
 111 #define BREAKPOINT32 0x10004
 112
 113 /* Amount PC must be decremented by after a breakpoint.
 114    This is often the number of bytes in BREAKPOINT
 115    but not always.
 116
 117    Not on the PA-RISC */
 118
 119 #define DECR_PC_AFTER_BREAK 0
 120
 121 /* Sometimes we may pluck out a minimal symbol that has a negative
 122    address.
 123
 124    An example of this occurs when an a.out is linked against a foo.sl.
 125    The foo.sl defines a global bar(), and the a.out declares a signature
 126    for bar().  However, the a.out doesn't directly call bar(), but passes
 127    its address in another call.
 128
 129    If you have this scenario and attempt to "break bar" before running,
 130    gdb will find a minimal symbol for bar() in the a.out.  But that
 131    symbol's address will be negative.  What this appears to denote is
 132    an index backwards from the base of the procedure linkage table (PLT)
 133    into the data linkage table (DLT), the end of which is contiguous
 134    with the start of the PLT.  This is clearly not a valid address for
 135    us to set a breakpoint on.
 136
 137    Note that one must be careful in how one checks for a negative address.
 138    0xc0000000 is a legitimate address of something in a shared text
 139    segment, for example.  Since I don't know what the possible range
 140    is of these "really, truly negative" addresses that come from the
 141    minimal symbols, I'm resorting to the gross hack of checking the
 142    top byte of the address for all 1's.  Sigh.
 143  */
 144 #define PC_REQUIRES_RUN_BEFORE_USE(pc) \
 145   (! target_has_stack && (pc & 0xFF000000))
 146
 147 /* return instruction is bv r0(rp) or bv,n r0(rp) */
 148
 149 #define ABOUT_TO_RETURN(pc) ((read_memory_integer (pc, 4) | 0x2) == 0xE840C002)
 150
 151 /* Say how long (ordinary) registers are.  This is a piece of bogosity
 152    used in push_word and a few other places; REGISTER_RAW_SIZE is the
 153    real way to know how big a register is.  */
 154
 155 #define REGISTER_SIZE 4
 156
 157 /* Number of machine registers */
 158
 159 #define NUM_REGS 128
 160
 161 /* Initializer for an array of names of registers.
 162    There should be NUM_REGS strings in this initializer.
 163    They are in rows of eight entries  */
 164
 165 #define REGISTER_NAMES  \
 166  {"flags",  "r1",      "rp",      "r3",    "r4",     "r5",      "r6",     "r7",    \
 167   "r8",     "r9",      "r10",     "r11",   "r12",    "r13",     "r14",    "r15",   \
 168   "r16",    "r17",     "r18",     "r19",   "r20",    "r21",     "r22",    "r23",   \
 169   "r24",    "r25",     "r26",     "dp",    "ret0",   "ret1",    "sp",     "r31",   \
 170   "sar",    "pcoqh",   "pcsqh",   "pcoqt", "pcsqt",  "eiem",    "iir",    "isr",   \
 171   "ior",    "ipsw",    "goto",    "sr4",   "sr0",    "sr1",     "sr2",    "sr3",   \
 172   "sr5",    "sr6",     "sr7",     "cr0",   "cr8",    "cr9",     "ccr",    "cr12",  \
 173   "cr13",   "cr24",    "cr25",    "cr26",  "mpsfu_high","mpsfu_low","mpsfu_ovflo","pad",\
 174   "fpsr",    "fpe1",   "fpe2",    "fpe3",  "fpe4",   "fpe5",    "fpe6",   "fpe7",  \
 175   "fr4",     "fr4R",   "fr5",     "fr5R",  "fr6",    "fr6R",    "fr7",    "fr7R",  \
 176   "fr8",     "fr8R",   "fr9",     "fr9R",  "fr10",   "fr10R",   "fr11",   "fr11R", \
 177   "fr12",    "fr12R",  "fr13",    "fr13R", "fr14",   "fr14R",   "fr15",   "fr15R", \
 178   "fr16",    "fr16R",  "fr17",    "fr17R", "fr18",   "fr18R",   "fr19",   "fr19R", \
 179   "fr20",    "fr20R",  "fr21",    "fr21R", "fr22",   "fr22R",   "fr23",   "fr23R", \
 180   "fr24",    "fr24R",  "fr25",    "fr25R", "fr26",   "fr26R",   "fr27",   "fr27R", \
 181   "fr28",    "fr28R",  "fr29",    "fr29R", "fr30",   "fr30R",   "fr31",   "fr31R"}
 182
 183 /* Register numbers of various important registers.
 184    Note that some of these values are "real" register numbers,
 185    and correspond to the general registers of the machine,
 186    and some are "phony" register numbers which are too large
 187    to be actual register numbers as far as the user is concerned
 188    but do serve to get the desired values when passed to read_register.  */
 189
 190 #define R0_REGNUM 0             /* Doesn't actually exist, used as base for
 191                                    other r registers.  */
 192 #define FLAGS_REGNUM 0          /* Various status flags */
 193 #define RP_REGNUM 2             /* return pointer */
 194 #define FP_REGNUM 3             /* Contains address of executing stack */
 195                                 /* frame */
 196 #define SP_REGNUM 30            /* Contains address of top of stack */
 197 #define SAR_REGNUM 32           /* Shift Amount Register */
 198 #define IPSW_REGNUM 41          /* Interrupt Processor Status Word */
 199 #define PCOQ_HEAD_REGNUM 33     /* instruction offset queue head */
 200 #define PCSQ_HEAD_REGNUM 34     /* instruction space queue head */
 201 #define PCOQ_TAIL_REGNUM 35     /* instruction offset queue tail */
 202 #define PCSQ_TAIL_REGNUM 36     /* instruction space queue tail */
 203 #define EIEM_REGNUM 37          /* External Interrupt Enable Mask */
 204 #define IIR_REGNUM 38           /* Interrupt Instruction Register */
 205 #define IOR_REGNUM 40           /* Interrupt Offset Register */
 206 #define SR4_REGNUM 43           /* space register 4 */
 207 #define RCR_REGNUM 51           /* Recover Counter (also known as cr0) */
 208 #define CCR_REGNUM 54           /* Coprocessor Configuration Register */
 209 #define TR0_REGNUM 57           /* Temporary Registers (cr24 -> cr31) */
 210 #define CR27_REGNUM 60          /* Base register for thread-local storage, cr27 */
 211 #define FP0_REGNUM 64           /* floating point reg. 0 (fspr) */
 212 #define FP4_REGNUM 72
 213
 214 #define ARG0_REGNUM 26          /* The first argument of a callee. */
 215 #define ARG1_REGNUM 25          /* The second argument of a callee. */
 216 #define ARG2_REGNUM 24          /* The third argument of a callee. */
 217 #define ARG3_REGNUM 23          /* The fourth argument of a callee. */
 218
 219 /* compatibility with the rest of gdb. */
 220 #define PC_REGNUM PCOQ_HEAD_REGNUM
 221 #define NPC_REGNUM PCOQ_TAIL_REGNUM
 222
 223 /*
 224  * Processor Status Word Masks
 225  */
 226
 227 #define PSW_T   0x01000000      /* Taken Branch Trap Enable */
 228 #define PSW_H   0x00800000      /* Higher-Privilege Transfer Trap Enable */
 229 #define PSW_L   0x00400000      /* Lower-Privilege Transfer Trap Enable */
 230 #define PSW_N   0x00200000      /* PC Queue Front Instruction Nullified */
 231 #define PSW_X   0x00100000      /* Data Memory Break Disable */
 232 #define PSW_B   0x00080000      /* Taken Branch in Previous Cycle */
 233 #define PSW_C   0x00040000      /* Code Address Translation Enable */
 234 #define PSW_V   0x00020000      /* Divide Step Correction */
 235 #define PSW_M   0x00010000      /* High-Priority Machine Check Disable */
 236 #define PSW_CB  0x0000ff00      /* Carry/Borrow Bits */
 237 #define PSW_R   0x00000010      /* Recovery Counter Enable */
 238 #define PSW_Q   0x00000008      /* Interruption State Collection Enable */
 239 #define PSW_P   0x00000004      /* Protection ID Validation Enable */
 240 #define PSW_D   0x00000002      /* Data Address Translation Enable */
 241 #define PSW_I   0x00000001      /* External, Power Failure, Low-Priority */
 242                                 /* Machine Check Interruption Enable */
 243
 244 /* When fetching register values from an inferior or a core file,
 245    clean them up using this macro.  BUF is a char pointer to
 246    the raw value of the register in the registers[] array.  */
 247
 248 #define DEPRECATED_CLEAN_UP_REGISTER_VALUE(regno, buf) \
 249   do {  \
 250     if ((regno) == PCOQ_HEAD_REGNUM || (regno) == PCOQ_TAIL_REGNUM) \
 251       (buf)[sizeof(CORE_ADDR) -1] &= ~0x3; \
 252   } while (0)
 253
 254 /* Define DEPRECATED_REGISTERS_INFO() to do machine-specific formatting
 255    of register dumps. */
 256
 257 #define DEPRECATED_REGISTERS_INFO(_regnum, fp) pa_do_registers_info (_regnum, fp)
 258 extern void pa_do_registers_info (int, int);
 259
 260 #if 0
 261 #define STRCAT_REGISTER(regnum, fpregs, stream, precision) pa_do_strcat_registers_info (regnum, fpregs, stream, precision)
 262 extern void pa_do_strcat_registers_info (int, int, struct ui_file *, enum precision_type);
 263 #endif
 264
 265 /* PA specific macro to see if the current instruction is nullified. */
 266 #ifndef INSTRUCTION_NULLIFIED
 267 #define INSTRUCTION_NULLIFIED \
 268     (((int)read_register (IPSW_REGNUM) & 0x00200000) && \
 269      !((int)read_register (FLAGS_REGNUM) & 0x2))
 270 #endif
 271
 272 /* Number of bytes of storage in the actual machine representation
 273    for register N.  On the PA-RISC, all regs are 4 bytes, including
 274    the FP registers (they're accessed as two 4 byte halves).  */
 275
 276 #define REGISTER_RAW_SIZE(N) 4
 277
 278 /* Total amount of space needed to store our copies of the machine's
 279    register state, the array `registers'.  */
 280 #define REGISTER_BYTES (NUM_REGS * 4)
 281
 282 /* Index within `registers' of the first byte of the space for
 283    register N.  */
 284
 285 #define REGISTER_BYTE(N) (N) * 4
 286
 287 /* Number of bytes of storage in the program's representation
 288    for register N. */
 289
 290 #define REGISTER_VIRTUAL_SIZE(N) REGISTER_RAW_SIZE(N)
 291
 292 /* Largest value REGISTER_RAW_SIZE can have.  */
 293
 294 #define MAX_REGISTER_RAW_SIZE 4
 295
 296 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 297
 298 #define MAX_REGISTER_VIRTUAL_SIZE 8
 299
 300 /* Return the GDB type object for the "standard" data type
 301    of data in register N.  */
 302
 303 #define REGISTER_VIRTUAL_TYPE(N) \
 304  ((N) < FP4_REGNUM ? builtin_type_int : builtin_type_float)
 305
 306 /* Store the address of the place in which to copy the structure the
 307    subroutine will return.  This is called from call_function. */
 308
 309 #define STORE_STRUCT_RETURN(ADDR, SP) {write_register (28, (ADDR)); }
 310
 311 /* Extract from an array REGBUF containing the (raw) register state
 312    a function return value of type TYPE, and copy that, in virtual format,
 313    into VALBUF.  */
 314
 315 void hppa_extract_return_value (struct type *type, char *regbuf, char *valbuf);
 316 #define DEPRECATED_EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 317   hppa_extract_return_value (TYPE, REGBUF, VALBUF);
 318
 319  /* elz: decide whether the function returning a value of type type
 320     will put it on the stack or in the registers.
 321     The pa calling convention says that:
 322     register 28 (called ret0 by gdb) contains any ASCII char,
 323     and any non_floating point value up to 32-bits.
 324     reg 28 and 29 contain non-floating point up tp 64 bits and larger
 325     than 32 bits. (higer order word in reg 28).
 326     fr4: floating point up to 64 bits
 327     sr1: space identifier (32-bit)
 328     stack: any lager than 64-bit, with the address in r28
 329   */
 330 extern use_struct_convention_fn hppa_use_struct_convention;
 331 #define USE_STRUCT_CONVENTION(gcc_p,type) hppa_use_struct_convention (gcc_p,type)
 332
 333 /* Write into appropriate registers a function return value
 334    of type TYPE, given in virtual format.  */
 335
 336
 337 extern void hppa_store_return_value (struct type *type, char *valbuf);
 338 #define DEPRECATED_STORE_RETURN_VALUE(TYPE,VALBUF) \
 339   hppa_store_return_value (TYPE, VALBUF);
 340
 341 /* Extract from an array REGBUF containing the (raw) register state
 342    the address in which a function should return its structure value,
 343    as a CORE_ADDR (or an expression that can be used as one).  */
 344
 345 #define DEPRECATED_EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) \
 346   (*(int *)((REGBUF) + REGISTER_BYTE (28)))
 347
 348 /* elz: Return a large value, which is stored on the stack at addr.
 349    This is defined only for the hppa, at this moment.  The above macro
 350    DEPRECATED_EXTRACT_STRUCT_VALUE_ADDRESS is not called anymore,
 351    because it assumes that on exit from a called function which
 352    returns a large structure on the stack, the address of the ret
 353    structure is still in register 28. Unfortunately this register is
 354    usually overwritten by the called function itself, on hppa. This is
 355    specified in the calling convention doc. As far as I know, the only
 356    way to get the return value is to have the caller tell us where it
 357    told the callee to put it, rather than have the callee tell us.  */
 358 struct value *hppa_value_returned_from_stack (register struct type *valtype,
 359                                               CORE_ADDR addr);
 360 #define VALUE_RETURNED_FROM_STACK(valtype,addr) \
 361   hppa_value_returned_from_stack (valtype, addr)
 362
 363 /*
 364  * This macro defines the register numbers (from REGISTER_NAMES) that
 365  * are effectively unavailable to the user through ptrace().  It allows
 366  * us to include the whole register set in REGISTER_NAMES (inorder to
 367  * better support remote debugging).  If it is used in
 368  * fetch/store_inferior_registers() gdb will not complain about I/O errors
 369  * on fetching these registers.  If all registers in REGISTER_NAMES
 370  * are available, then return false (0).
 371  */
 372
 373 #define CANNOT_STORE_REGISTER(regno)            \
 374                    ((regno) == 0) ||     \
 375                    ((regno) == PCSQ_HEAD_REGNUM) || \
 376                    ((regno) >= PCSQ_TAIL_REGNUM && (regno) < IPSW_REGNUM) ||  \
 377                    ((regno) > IPSW_REGNUM && (regno) < FP4_REGNUM)
 378
 379 #define INIT_EXTRA_FRAME_INFO(fromleaf, frame) init_extra_frame_info (fromleaf, frame)
 380 extern void init_extra_frame_info (int, struct frame_info *);
 381
 382 /* Describe the pointer in each stack frame to the previous stack frame
 383    (its caller).  */
 384
 385 /* FRAME_CHAIN takes a frame's nominal address and produces the
 386    frame's chain-pointer.  */
 387
 388 /* In the case of the PA-RISC, the frame's nominal address
 389    is the address of a 4-byte word containing the calling frame's
 390    address (previous FP).  */
 391
 392 #define FRAME_CHAIN(thisframe) frame_chain (thisframe)
 393 extern CORE_ADDR frame_chain (struct frame_info *);
 394
 395 extern int hppa_frame_chain_valid (CORE_ADDR, struct frame_info *);
 396 #define FRAME_CHAIN_VALID(chain, thisframe) hppa_frame_chain_valid (chain, thisframe)
 397
 398 /* Define other aspects of the stack frame.  */
 399
 400 /* A macro that tells us whether the function invocation represented
 401    by FI does not have a frame on the stack associated with it.  If it
 402    does not, FRAMELESS is set to 1, else 0.  */
 403 #define FRAMELESS_FUNCTION_INVOCATION(FI) \
 404   (frameless_function_invocation (FI))
 405 extern int frameless_function_invocation (struct frame_info *);
 406
 407 extern CORE_ADDR hppa_frame_saved_pc (struct frame_info *frame);
 408 #define FRAME_SAVED_PC(FRAME) hppa_frame_saved_pc (FRAME)
 409
 410 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 411
 412 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 413 /* Set VAL to the number of args passed to frame described by FI.
 414    Can set VAL to -1, meaning no way to tell.  */
 415
 416 /* We can't tell how many args there are
 417    now that the C compiler delays popping them.  */
 418 #define FRAME_NUM_ARGS(fi) (-1)
 419
 420 /* Return number of bytes at start of arglist that are not really args.  */
 421
 422 #define FRAME_ARGS_SKIP 0
 423
 424 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 425   hppa_frame_find_saved_regs (frame_info, &frame_saved_regs)
 426 extern void
 427 hppa_frame_find_saved_regs (struct frame_info *, struct frame_saved_regs *);
 428 \f
 429
 430 /* Things needed for making the inferior call functions.  */
 431
 432 /* Push an empty stack frame, to record the current PC, etc. */
 433
 434 #define PUSH_DUMMY_FRAME push_dummy_frame (inf_status)
 435 extern void push_dummy_frame (struct inferior_status *);
 436
 437 /* Discard from the stack the innermost frame,
 438    restoring all saved registers.  */
 439 #define POP_FRAME  hppa_pop_frame ()
 440 extern void hppa_pop_frame (void);
 441
 442 #define INSTRUCTION_SIZE 4
 443
 444 #ifndef PA_LEVEL_0
 445
 446 /* Non-level zero PA's have space registers (but they don't always have
 447    floating-point, do they????  */
 448
 449 /* This sequence of words is the instructions
 450
 451    ; Call stack frame has already been built by gdb. Since we could be calling
 452    ; a varargs function, and we do not have the benefit of a stub to put things in
 453    ; the right place, we load the first 4 word of arguments into both the general
 454    ; and fp registers.
 455    call_dummy
 456    ldw -36(sp), arg0
 457    ldw -40(sp), arg1
 458    ldw -44(sp), arg2
 459    ldw -48(sp), arg3
 460    ldo -36(sp), r1
 461    fldws 0(0, r1), fr4
 462    fldds -4(0, r1), fr5
 463    fldws -8(0, r1), fr6
 464    fldds -12(0, r1), fr7
 465    ldil 0, r22                  ; FUNC_LDIL_OFFSET must point here
 466    ldo 0(r22), r22                      ; FUNC_LDO_OFFSET must point here
 467    ldsid (0,r22), r4
 468    ldil 0, r1                   ; SR4EXPORT_LDIL_OFFSET must point here
 469    ldo 0(r1), r1                        ; SR4EXPORT_LDO_OFFSET must point here
 470    ldsid (0,r1), r20
 471    combt,=,n r4, r20, text_space        ; If target is in data space, do a
 472    ble 0(sr5, r22)                      ; "normal" procedure call
 473    copy r31, r2
 474    break 4, 8
 475    mtsp r21, sr0
 476    ble,n 0(sr0, r22)
 477    text_space                           ; Otherwise, go through _sr4export,
 478    ble (sr4, r1)                        ; which will return back here.
 479    stw r31,-24(r30)
 480    break 4, 8
 481    mtsp r21, sr0
 482    ble,n 0(sr0, r22)
 483    nop                          ; To avoid kernel bugs
 484    nop                          ; and keep the dummy 8 byte aligned
 485
 486    The dummy decides if the target is in text space or data space. If
 487    it's in data space, there's no problem because the target can
 488    return back to the dummy. However, if the target is in text space,
 489    the dummy calls the secret, undocumented routine _sr4export, which
 490    calls a function in text space and can return to any space. Instead
 491    of including fake instructions to represent saved registers, we
 492    know that the frame is associated with the call dummy and treat it
 493    specially.
 494
 495    The trailing NOPs are needed to avoid a bug in HPUX, BSD and OSF1
 496    kernels.   If the memory at the location pointed to by the PC is
 497    0xffffffff then a ptrace step call will fail (even if the instruction
 498    is nullified).
 499
 500    The code to pop a dummy frame single steps three instructions
 501    starting with the last mtsp.  This includes the nullified "instruction"
 502    following the ble (which is uninitialized junk).  If the
 503    "instruction" following the last BLE is 0xffffffff, then the ptrace
 504    will fail and the dummy frame is not correctly popped.
 505
 506    By placing a NOP in the delay slot of the BLE instruction we can be
 507    sure that we never try to execute a 0xffffffff instruction and
 508    avoid the kernel bug.  The second NOP is needed to keep the call
 509    dummy 8 byte aligned.  */
 510
 511 /* Define offsets into the call dummy for the target function address */
 512 #define FUNC_LDIL_OFFSET (INSTRUCTION_SIZE * 9)
 513 #define FUNC_LDO_OFFSET (INSTRUCTION_SIZE * 10)
 514
 515 /* Define offsets into the call dummy for the _sr4export address */
 516 #define SR4EXPORT_LDIL_OFFSET (INSTRUCTION_SIZE * 12)
 517 #define SR4EXPORT_LDO_OFFSET (INSTRUCTION_SIZE * 13)
 518
 519 #define CALL_DUMMY {0x4BDA3FB9, 0x4BD93FB1, 0x4BD83FA9, 0x4BD73FA1,\
 520                     0x37C13FB9, 0x24201004, 0x2C391005, 0x24311006,\
 521                     0x2C291007, 0x22C00000, 0x36D60000, 0x02C010A4,\
 522                     0x20200000, 0x34210000, 0x002010b4, 0x82842022,\
 523                     0xe6c06000, 0x081f0242, 0x00010004, 0x00151820,\
 524                     0xe6c00002, 0xe4202000, 0x6bdf3fd1, 0x00010004,\
 525                     0x00151820, 0xe6c00002, 0x08000240, 0x08000240}
 526
 527 #define CALL_DUMMY_LENGTH (INSTRUCTION_SIZE * 28)
 528 #define REG_PARM_STACK_SPACE 16
 529
 530 #else /* defined PA_LEVEL_0 */
 531
 532 /* This is the call dummy for a level 0 PA.  Level 0's don't have space
 533    registers (or floating point?), so we skip all that inter-space call stuff,
 534    and avoid touching the fp regs.
 535
 536    call_dummy
 537
 538    ldw -36(%sp), %arg0
 539    ldw -40(%sp), %arg1
 540    ldw -44(%sp), %arg2
 541    ldw -48(%sp), %arg3
 542    ldil 0, %r31                 ; FUNC_LDIL_OFFSET must point here
 543    ldo 0(%r31), %r31            ; FUNC_LDO_OFFSET must point here
 544    ble 0(%sr0, %r31)
 545    copy %r31, %r2
 546    break 4, 8
 547    nop                          ; restore_pc_queue expects these
 548    bv,n 0(%r22)                 ; instructions to be here...
 549    nop
 550  */
 551
 552 /* Define offsets into the call dummy for the target function address */
 553 #define FUNC_LDIL_OFFSET (INSTRUCTION_SIZE * 4)
 554 #define FUNC_LDO_OFFSET (INSTRUCTION_SIZE * 5)
 555
 556 #define CALL_DUMMY {0x4bda3fb9, 0x4bd93fb1, 0x4bd83fa9, 0x4bd73fa1,\
 557                     0x23e00000, 0x37ff0000, 0xe7e00000, 0x081f0242,\
 558                     0x00010004, 0x08000240, 0xeac0c002, 0x08000240}
 559
 560 #define CALL_DUMMY_LENGTH (INSTRUCTION_SIZE * 12)
 561
 562 #endif
 563
 564 #define CALL_DUMMY_START_OFFSET 0
 565
 566 /* If we've reached a trap instruction within the call dummy, then
 567    we'll consider that to mean that we've reached the call dummy's
 568    end after its successful completion. */
 569 #define CALL_DUMMY_HAS_COMPLETED(pc, sp, frame_address) \
 570   (PC_IN_CALL_DUMMY((pc), (sp), (frame_address)) && \
 571    (read_memory_integer((pc), 4) == BREAKPOINT32))
 572
 573 /*
 574  * Insert the specified number of args and function address
 575  * into a call sequence of the above form stored at DUMMYNAME.
 576  *
 577  * On the hppa we need to call the stack dummy through $$dyncall.
 578  * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
 579  * real_pc, which is the location where gdb should start up the
 580  * inferior to do the function call.
 581  */
 582
 583 #define FIX_CALL_DUMMY hppa_fix_call_dummy
 584
 585 extern CORE_ADDR
 586 hppa_fix_call_dummy (char *, CORE_ADDR, CORE_ADDR, int,
 587                      struct value **, struct type *, int);
 588
 589 #define PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr) \
 590   (hppa_push_arguments((nargs), (args), (sp), (struct_return), (struct_addr)))
 591 extern CORE_ADDR
 592 hppa_push_arguments (int, struct value **, CORE_ADDR, int, CORE_ADDR);
 593 \f
 594 /* The low two bits of the PC on the PA contain the privilege level.  Some
 595    genius implementing a (non-GCC) compiler apparently decided this means
 596    that "addresses" in a text section therefore include a privilege level,
 597    and thus symbol tables should contain these bits.  This seems like a
 598    bonehead thing to do--anyway, it seems to work for our purposes to just
 599    ignore those bits.  */
 600 #define SMASH_TEXT_ADDRESS(addr) ((addr) &= ~0x3)
 601
 602 #define GDB_TARGET_IS_HPPA
 603
 604 #define BELIEVE_PCC_PROMOTION 1
 605
 606 /*
 607  * Unwind table and descriptor.
 608  */
 609
 610 struct unwind_table_entry
 611   {
 612     CORE_ADDR region_start;
 613     CORE_ADDR region_end;
 614
 615     unsigned int Cannot_unwind:1;       /* 0 */
 616     unsigned int Millicode:1;   /* 1 */
 617     unsigned int Millicode_save_sr0:1;  /* 2 */
 618     unsigned int Region_description:2;  /* 3..4 */
 619     unsigned int reserved1:1;   /* 5 */
 620     unsigned int Entry_SR:1;    /* 6 */
 621     unsigned int Entry_FR:4;    /* number saved *//* 7..10 */
 622     unsigned int Entry_GR:5;    /* number saved *//* 11..15 */
 623     unsigned int Args_stored:1; /* 16 */
 624     unsigned int Variable_Frame:1;      /* 17 */
 625     unsigned int Separate_Package_Body:1;       /* 18 */
 626     unsigned int Frame_Extension_Millicode:1;   /* 19 */
 627     unsigned int Stack_Overflow_Check:1;        /* 20 */
 628     unsigned int Two_Instruction_SP_Increment:1;        /* 21 */
 629     unsigned int Ada_Region:1;  /* 22 */
 630     unsigned int cxx_info:1;    /* 23 */
 631     unsigned int cxx_try_catch:1;       /* 24 */
 632     unsigned int sched_entry_seq:1;     /* 25 */
 633     unsigned int reserved2:1;   /* 26 */
 634     unsigned int Save_SP:1;     /* 27 */
 635     unsigned int Save_RP:1;     /* 28 */
 636     unsigned int Save_MRP_in_frame:1;   /* 29 */
 637     unsigned int extn_ptr_defined:1;    /* 30 */
 638     unsigned int Cleanup_defined:1;     /* 31 */
 639
 640     unsigned int MPE_XL_interrupt_marker:1;     /* 0 */
 641     unsigned int HP_UX_interrupt_marker:1;      /* 1 */
 642     unsigned int Large_frame:1; /* 2 */
 643     unsigned int Pseudo_SP_Set:1;       /* 3 */
 644     unsigned int reserved4:1;   /* 4 */
 645     unsigned int Total_frame_size:27;   /* 5..31 */
 646
 647     /* This is *NOT* part of an actual unwind_descriptor in an object
 648        file.  It is *ONLY* part of the "internalized" descriptors that
 649        we create from those in a file.
 650      */
 651     struct
 652       {
 653         unsigned int stub_type:4;       /* 0..3 */
 654         unsigned int padding:28;        /* 4..31 */
 655       }
 656     stub_unwind;
 657   };
 658
 659 /* HP linkers also generate unwinds for various linker-generated stubs.
 660    GDB reads in the stubs from the $UNWIND_END$ subspace, then
 661    "converts" them into normal unwind entries using some of the reserved
 662    fields to store the stub type.  */
 663
 664 struct stub_unwind_entry
 665   {
 666     /* The offset within the executable for the associated stub.  */
 667     unsigned stub_offset;
 668
 669     /* The type of stub this unwind entry describes.  */
 670     char type;
 671
 672     /* Unknown.  Not needed by GDB at this time.  */
 673     char prs_info;
 674
 675     /* Length (in instructions) of the associated stub.  */
 676     short stub_length;
 677   };
 678
 679 /* Sizes (in bytes) of the native unwind entries.  */
 680 #define UNWIND_ENTRY_SIZE 16
 681 #define STUB_UNWIND_ENTRY_SIZE 8
 682
 683 /* The gaps represent linker stubs used in MPE and space for future
 684    expansion.  */
 685 enum unwind_stub_types
 686   {
 687     LONG_BRANCH = 1,
 688     PARAMETER_RELOCATION = 2,
 689     EXPORT = 10,
 690     IMPORT = 11,
 691     IMPORT_SHLIB = 12,
 692   };
 693
 694 /* We use the objfile->obj_private pointer for two things:
 695
 696  * 1.  An unwind table;
 697  *
 698  * 2.  A pointer to any associated shared library object.
 699  *
 700  * #defines are used to help refer to these objects.
 701  */
 702
 703 /* Info about the unwind table associated with an object file.
 704
 705  * This is hung off of the "objfile->obj_private" pointer, and
 706  * is allocated in the objfile's psymbol obstack.  This allows
 707  * us to have unique unwind info for each executable and shared
 708  * library that we are debugging.
 709  */
 710 struct obj_unwind_info
 711   {
 712     struct unwind_table_entry *table;   /* Pointer to unwind info */
 713     struct unwind_table_entry *cache;   /* Pointer to last entry we found */
 714     int last;                   /* Index of last entry */
 715   };
 716
 717 typedef struct obj_private_struct
 718   {
 719     struct obj_unwind_info *unwind_info;        /* a pointer */
 720     struct so_list *so_info;    /* a pointer  */
 721     CORE_ADDR dp;
 722   }
 723 obj_private_data_t;
 724
 725 #if 0
 726 extern void target_write_pc (CORE_ADDR, int);
 727 extern CORE_ADDR target_read_pc (int);
 728 extern CORE_ADDR skip_trampoline_code (CORE_ADDR, char *);
 729 #endif
 730
 731 #define TARGET_READ_PC(pid) target_read_pc (pid)
 732 extern CORE_ADDR target_read_pc (ptid_t);
 733
 734 #define TARGET_WRITE_PC(v,pid) target_write_pc (v,pid)
 735 extern void target_write_pc (CORE_ADDR, ptid_t);
 736
 737 #define TARGET_READ_FP() target_read_fp (PIDGET (inferior_ptid))
 738 extern CORE_ADDR target_read_fp (int);
 739
 740 /* For a number of horrible reasons we may have to adjust the location
 741    of variables on the stack.  Ugh.  */
 742 #define HPREAD_ADJUST_STACK_ADDRESS(ADDR) hpread_adjust_stack_address(ADDR)
 743
 744 extern int hpread_adjust_stack_address (CORE_ADDR);
 745
 746 /* If the current gcc for for this target does not produce correct debugging
 747    information for float parameters, both prototyped and unprototyped, then
 748    define this macro.  This forces gdb to  always assume that floats are
 749    passed as doubles and then converted in the callee.
 750
 751    For the pa, it appears that the debug info marks the parameters as
 752    floats regardless of whether the function is prototyped, but the actual
 753    values are passed as doubles for the non-prototyped case and floats for
 754    the prototyped case.  Thus we choose to make the non-prototyped case work
 755    for C and break the prototyped case, since the non-prototyped case is
 756    probably much more common.  (FIXME). */
 757
 758 #define COERCE_FLOAT_TO_DOUBLE(formal, actual) (current_language -> la_language == language_c)
 759
 760 /* Here's how to step off a permanent breakpoint.  */
 761 #define SKIP_PERMANENT_BREAKPOINT (hppa_skip_permanent_breakpoint)
 762 extern void hppa_skip_permanent_breakpoint (void);
 763
 764 /* On HP-UX, certain system routines (millicode) have names beginning
 765    with $ or $$, e.g. $$dyncall, which handles inter-space procedure
 766    calls on PA-RISC.  Tell the expression parser to check for those
 767    when parsing tokens that begin with "$".  */
 768 #define SYMBOLS_CAN_START_WITH_DOLLAR (1)