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