gdb/hppa-tdep.c

   1 /* Machine-dependent code which would otherwise be in inflow.c and core.c,
   2    for GDB, the GNU debugger.  This code is for the HP PA-RISC cpu.
   3    Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993 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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  23
  24 #include "defs.h"
  25 #include "frame.h"
  26 #include "inferior.h"
  27 #include "value.h"
  28
  29 /* For argument passing to the inferior */
  30 #include "symtab.h"
  31
  32 #ifdef USG
  33 #include <sys/types.h>
  34 #endif
  35
  36 #include <sys/param.h>
  37 #include <sys/dir.h>
  38 #include <signal.h>
  39 #include <sys/ioctl.h>
  40
  41 #ifdef COFF_ENCAPSULATE
  42 #include "a.out.encap.h"
  43 #else
  44 #include <a.out.h>
  45 #endif
  46 #ifndef N_SET_MAGIC
  47 #define N_SET_MAGIC(exec, val) ((exec).a_magic = (val))
  48 #endif
  49
  50 /*#include <sys/user.h>         After a.out.h  */
  51 #include <sys/file.h>
  52 #include <sys/stat.h>
  53 #include <machine/psl.h>
  54 #include "wait.h"
  55
  56 #include "gdbcore.h"
  57 #include "gdbcmd.h"
  58 #include "target.h"
  59 #include "symfile.h"
  60 #include "objfiles.h"
  61
  62 static int restore_pc_queue PARAMS ((struct frame_saved_regs *fsr));
  63 static int hppa_alignof PARAMS ((struct type *arg));
  64 CORE_ADDR frame_saved_pc PARAMS ((FRAME frame));
  65
  66 \f
  67 /* Routines to extract various sized constants out of hppa
  68    instructions. */
  69
  70 /* This assumes that no garbage lies outside of the lower bits of
  71    value. */
  72
  73 int
  74 sign_extend (val, bits)
  75      unsigned val, bits;
  76 {
  77   return (int)(val >> bits - 1 ? (-1 << bits) | val : val);
  78 }
  79
  80 /* For many immediate values the sign bit is the low bit! */
  81
  82 int
  83 low_sign_extend (val, bits)
  84      unsigned val, bits;
  85 {
  86   return (int)((val & 0x1 ? (-1 << (bits - 1)) : 0) | val >> 1);
  87 }
  88 /* extract the immediate field from a ld{bhw}s instruction */
  89
  90 unsigned
  91 get_field (val, from, to)
  92      unsigned val, from, to;
  93 {
  94   val = val >> 31 - to;
  95   return val & ((1 << 32 - from) - 1);
  96 }
  97
  98 unsigned
  99 set_field (val, from, to, new_val)
 100      unsigned *val, from, to;
 101 {
 102   unsigned mask = ~((1 << (to - from + 1)) << (31 - from));
 103   return *val = *val & mask | (new_val << (31 - from));
 104 }
 105
 106 /* extract a 3-bit space register number from a be, ble, mtsp or mfsp */
 107
 108 extract_3 (word)
 109      unsigned word;
 110 {
 111   return GET_FIELD (word, 18, 18) << 2 | GET_FIELD (word, 16, 17);
 112 }
 113
 114 extract_5_load (word)
 115      unsigned word;
 116 {
 117   return low_sign_extend (word >> 16 & MASK_5, 5);
 118 }
 119
 120 /* extract the immediate field from a st{bhw}s instruction */
 121
 122 int
 123 extract_5_store (word)
 124      unsigned word;
 125 {
 126   return low_sign_extend (word & MASK_5, 5);
 127 }
 128
 129 /* extract the immediate field from a break instruction */
 130
 131 unsigned
 132 extract_5r_store (word)
 133      unsigned word;
 134 {
 135   return (word & MASK_5);
 136 }
 137
 138 /* extract the immediate field from a {sr}sm instruction */
 139
 140 unsigned
 141 extract_5R_store (word)
 142      unsigned word;
 143 {
 144   return (word >> 16 & MASK_5);
 145 }
 146
 147 /* extract an 11 bit immediate field */
 148
 149 int
 150 extract_11 (word)
 151      unsigned word;
 152 {
 153   return low_sign_extend (word & MASK_11, 11);
 154 }
 155
 156 /* extract a 14 bit immediate field */
 157
 158 int
 159 extract_14 (word)
 160      unsigned word;
 161 {
 162   return low_sign_extend (word & MASK_14, 14);
 163 }
 164
 165 /* deposit a 14 bit constant in a word */
 166
 167 unsigned
 168 deposit_14 (opnd, word)
 169      int opnd;
 170      unsigned word;
 171 {
 172   unsigned sign = (opnd < 0 ? 1 : 0);
 173
 174   return word | ((unsigned)opnd << 1 & MASK_14)  | sign;
 175 }
 176
 177 /* extract a 21 bit constant */
 178
 179 int
 180 extract_21 (word)
 181      unsigned word;
 182 {
 183   int val;
 184
 185   word &= MASK_21;
 186   word <<= 11;
 187   val = GET_FIELD (word, 20, 20);
 188   val <<= 11;
 189   val |= GET_FIELD (word, 9, 19);
 190   val <<= 2;
 191   val |= GET_FIELD (word, 5, 6);
 192   val <<= 5;
 193   val |= GET_FIELD (word, 0, 4);
 194   val <<= 2;
 195   val |= GET_FIELD (word, 7, 8);
 196   return sign_extend (val, 21) << 11;
 197 }
 198
 199 /* deposit a 21 bit constant in a word. Although 21 bit constants are
 200    usually the top 21 bits of a 32 bit constant, we assume that only
 201    the low 21 bits of opnd are relevant */
 202
 203 unsigned
 204 deposit_21 (opnd, word)
 205      unsigned opnd, word;
 206 {
 207   unsigned val = 0;
 208
 209   val |= GET_FIELD (opnd, 11 + 14, 11 + 18);
 210   val <<= 2;
 211   val |= GET_FIELD (opnd, 11 + 12, 11 + 13);
 212   val <<= 2;
 213   val |= GET_FIELD (opnd, 11 + 19, 11 + 20);
 214   val <<= 11;
 215   val |= GET_FIELD (opnd, 11 + 1, 11 + 11);
 216   val <<= 1;
 217   val |= GET_FIELD (opnd, 11 + 0, 11 + 0);
 218   return word | val;
 219 }
 220
 221 /* extract a 12 bit constant from branch instructions */
 222
 223 int
 224 extract_12 (word)
 225      unsigned word;
 226 {
 227   return sign_extend (GET_FIELD (word, 19, 28) |
 228                       GET_FIELD (word, 29, 29) << 10 |
 229                       (word & 0x1) << 11, 12) << 2;
 230 }
 231
 232 /* extract a 17 bit constant from branch instructions, returning the
 233    19 bit signed value. */
 234
 235 int
 236 extract_17 (word)
 237      unsigned word;
 238 {
 239   return sign_extend (GET_FIELD (word, 19, 28) |
 240                       GET_FIELD (word, 29, 29) << 10 |
 241                       GET_FIELD (word, 11, 15) << 11 |
 242                       (word & 0x1) << 16, 17) << 2;
 243 }
 244 \f
 245 static int use_unwind = 0;
 246
 247 /* Lookup the unwind (stack backtrace) info for the given PC.  We search all
 248    of the objfiles seeking the unwind table entry for this PC.  Each objfile
 249    contains a sorted list of struct unwind_table_entry.  Since we do a binary
 250    search of the unwind tables, we depend upon them to be sorted.  */
 251
 252 static struct unwind_table_entry *
 253 find_unwind_entry(pc)
 254      CORE_ADDR pc;
 255 {
 256   int first, middle, last;
 257   struct objfile *objfile;
 258
 259   ALL_OBJFILES (objfile)
 260     {
 261       struct obj_unwind_info *ui;
 262
 263       ui = OBJ_UNWIND_INFO (objfile);
 264
 265       if (!ui)
 266         continue;
 267
 268       /* First, check the cache */
 269
 270       if (ui->cache
 271           && pc >= ui->cache->region_start
 272           && pc <= ui->cache->region_end)
 273         return ui->cache;
 274
 275       /* Not in the cache, do a binary search */
 276
 277       first = 0;
 278       last = ui->last;
 279
 280       while (first <= last)
 281         {
 282           middle = (first + last) / 2;
 283           if (pc >= ui->table[middle].region_start
 284               && pc <= ui->table[middle].region_end)
 285             {
 286               ui->cache = &ui->table[middle];
 287               return &ui->table[middle];
 288             }
 289
 290           if (pc < ui->table[middle].region_start)
 291             last = middle - 1;
 292           else
 293             first = middle + 1;
 294         }
 295     }                           /* ALL_OBJFILES() */
 296   return NULL;
 297 }
 298
 299 static int
 300 find_return_regnum(pc)
 301      CORE_ADDR pc;
 302 {
 303   struct unwind_table_entry *u;
 304
 305   u = find_unwind_entry (pc);
 306
 307   if (!u)
 308     return RP_REGNUM;
 309
 310   if (u->Millicode)
 311     return 31;
 312
 313   return RP_REGNUM;
 314 }
 315
 316 int
 317 find_proc_framesize(pc)
 318      CORE_ADDR pc;
 319 {
 320   struct unwind_table_entry *u;
 321
 322   if (!use_unwind)
 323     return -1;
 324
 325   u = find_unwind_entry (pc);
 326
 327   if (!u)
 328     return -1;
 329
 330   if (u->Save_SP)
 331     /* If this bit is set, it means there is a frame pointer and we should
 332        use it.  */
 333     return -1;
 334
 335   return u->Total_frame_size << 3;
 336 }
 337
 338 int
 339 rp_saved(pc)
 340 {
 341   struct unwind_table_entry *u;
 342
 343   u = find_unwind_entry (pc);
 344
 345   if (!u)
 346     return 0;
 347
 348   if (u->Save_RP)
 349     return 1;
 350   else
 351     return 0;
 352 }
 353 \f
 354 int
 355 frameless_function_invocation (frame)
 356      FRAME frame;
 357 {
 358
 359   if (use_unwind)
 360     {
 361       struct unwind_table_entry *u;
 362
 363       u = find_unwind_entry (frame->pc);
 364
 365       if (u == 0)
 366         return 0;
 367
 368       return (u->Total_frame_size == 0);
 369     }
 370   else
 371     return frameless_look_for_prologue (frame);
 372 }
 373
 374 CORE_ADDR
 375 saved_pc_after_call (frame)
 376      FRAME frame;
 377 {
 378   int ret_regnum;
 379
 380   ret_regnum = find_return_regnum (get_frame_pc (frame));
 381
 382   return read_register (ret_regnum) & ~0x3;
 383 }
 384 \f
 385 CORE_ADDR
 386 frame_saved_pc (frame)
 387      FRAME frame;
 388 {
 389   CORE_ADDR pc = get_frame_pc (frame);
 390
 391   if (frameless_function_invocation (frame))
 392     {
 393       int ret_regnum;
 394
 395       ret_regnum = find_return_regnum (pc);
 396
 397       return read_register (ret_regnum) & ~0x3;
 398     }
 399   else if (rp_saved (pc))
 400     return read_memory_integer (frame->frame - 20, 4) & ~0x3;
 401   else
 402     return read_register (RP_REGNUM) & ~0x3;
 403 }
 404 \f
 405 /* We need to correct the PC and the FP for the outermost frame when we are
 406    in a system call.  */
 407
 408 void
 409 init_extra_frame_info (fromleaf, frame)
 410      int fromleaf;
 411      struct frame_info *frame;
 412 {
 413   int flags;
 414   int framesize;
 415
 416   if (frame->next)              /* Only do this for outermost frame */
 417     return;
 418
 419   flags = read_register (FLAGS_REGNUM);
 420   if (flags & 2)        /* In system call? */
 421     frame->pc = read_register (31) & ~0x3;
 422
 423   /* The outermost frame is always derived from PC-framesize */
 424   framesize = find_proc_framesize(frame->pc);
 425   if (framesize == -1)
 426     frame->frame = read_register (FP_REGNUM);
 427   else
 428     frame->frame = read_register (SP_REGNUM) - framesize;
 429
 430   if (!frameless_function_invocation (frame)) /* Frameless? */
 431     return;                                 /* No, quit now */
 432
 433   /* For frameless functions, we need to look at the caller's frame */
 434   framesize = find_proc_framesize(FRAME_SAVED_PC(frame));
 435   if (framesize != -1)
 436     frame->frame -= framesize;
 437 }
 438 \f
 439 FRAME_ADDR
 440 frame_chain (frame)
 441      struct frame_info *frame;
 442 {
 443   int framesize;
 444
 445   framesize = find_proc_framesize(FRAME_SAVED_PC(frame));
 446
 447   if (framesize != -1)
 448     return frame->frame - framesize;
 449
 450   return read_memory_integer (frame->frame, 4);
 451 }
 452 \f
 453 /* To see if a frame chain is valid, see if the caller looks like it
 454    was compiled with gcc. */
 455
 456 int
 457 frame_chain_valid (chain, thisframe)
 458      FRAME_ADDR chain;
 459      FRAME thisframe;
 460 {
 461   struct minimal_symbol *msym;
 462
 463   if (!chain)
 464     return 0;
 465
 466   if (use_unwind)
 467     {
 468
 469       struct unwind_table_entry *u;
 470
 471       u = find_unwind_entry (thisframe->pc);
 472
 473       if (u && (u->Save_SP || u->Total_frame_size))
 474         return 1;
 475       else
 476         return 0;
 477     }
 478   else
 479     {
 480       msym = lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe));
 481
 482       if (msym
 483           && (strcmp (SYMBOL_NAME (msym), "_start") == 0))
 484         return 0;
 485       else
 486         return 1;
 487     }
 488 }
 489
 490 /*
 491  * These functions deal with saving and restoring register state
 492  * around a function call in the inferior. They keep the stack
 493  * double-word aligned; eventually, on an hp700, the stack will have
 494  * to be aligned to a 64-byte boundary.
 495  */
 496
 497 int
 498 push_dummy_frame ()
 499 {
 500   register CORE_ADDR sp;
 501   register int regnum;
 502   int int_buffer;
 503   double freg_buffer;
 504
 505   /* Space for "arguments"; the RP goes in here. */
 506   sp = read_register (SP_REGNUM) + 48;
 507   int_buffer = read_register (RP_REGNUM) | 0x3;
 508   write_memory (sp - 20, (char *)&int_buffer, 4);
 509
 510   int_buffer = read_register (FP_REGNUM);
 511   write_memory (sp, (char *)&int_buffer, 4);
 512
 513   write_register (FP_REGNUM, sp);
 514
 515   sp += 8;
 516
 517   for (regnum = 1; regnum < 32; regnum++)
 518     if (regnum != RP_REGNUM && regnum != FP_REGNUM)
 519       sp = push_word (sp, read_register (regnum));
 520
 521   sp += 4;
 522
 523   for (regnum = FP0_REGNUM; regnum < NUM_REGS; regnum++)
 524     {
 525       read_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
 526       sp = push_bytes (sp, (char *)&freg_buffer, 8);
 527     }
 528   sp = push_word (sp, read_register (IPSW_REGNUM));
 529   sp = push_word (sp, read_register (SAR_REGNUM));
 530   sp = push_word (sp, read_register (PCOQ_HEAD_REGNUM));
 531   sp = push_word (sp, read_register (PCSQ_HEAD_REGNUM));
 532   sp = push_word (sp, read_register (PCOQ_TAIL_REGNUM));
 533   sp = push_word (sp, read_register (PCSQ_TAIL_REGNUM));
 534   write_register (SP_REGNUM, sp);
 535 }
 536
 537 find_dummy_frame_regs (frame, frame_saved_regs)
 538      struct frame_info *frame;
 539      struct frame_saved_regs *frame_saved_regs;
 540 {
 541   CORE_ADDR fp = frame->frame;
 542   int i;
 543
 544   frame_saved_regs->regs[RP_REGNUM] = fp - 20 & ~0x3;
 545   frame_saved_regs->regs[FP_REGNUM] = fp;
 546   frame_saved_regs->regs[1] = fp + 8;
 547
 548   for (fp += 12, i = 3; i < 32; i++)
 549     {
 550       if (i != FP_REGNUM)
 551         {
 552           frame_saved_regs->regs[i] = fp;
 553           fp += 4;
 554         }
 555     }
 556
 557   fp += 4;
 558   for (i = FP0_REGNUM; i < NUM_REGS; i++, fp += 8)
 559     frame_saved_regs->regs[i] = fp;
 560
 561   frame_saved_regs->regs[IPSW_REGNUM] = fp;
 562   frame_saved_regs->regs[SAR_REGNUM] = fp + 4;
 563   frame_saved_regs->regs[PCOQ_HEAD_REGNUM] = fp + 8;
 564   frame_saved_regs->regs[PCSQ_HEAD_REGNUM] = fp + 12;
 565   frame_saved_regs->regs[PCOQ_TAIL_REGNUM] = fp + 16;
 566   frame_saved_regs->regs[PCSQ_TAIL_REGNUM] = fp + 20;
 567 }
 568
 569 int
 570 hppa_pop_frame ()
 571 {
 572   register FRAME frame = get_current_frame ();
 573   register CORE_ADDR fp;
 574   register int regnum;
 575   struct frame_saved_regs fsr;
 576   struct frame_info *fi;
 577   double freg_buffer;
 578
 579   fi = get_frame_info (frame);
 580   fp = fi->frame;
 581   get_frame_saved_regs (fi, &fsr);
 582
 583   if (fsr.regs[IPSW_REGNUM])    /* Restoring a call dummy frame */
 584     restore_pc_queue (&fsr);
 585
 586   for (regnum = 31; regnum > 0; regnum--)
 587     if (fsr.regs[regnum])
 588       write_register (regnum, read_memory_integer (fsr.regs[regnum], 4));
 589
 590   for (regnum = NUM_REGS - 1; regnum >= FP0_REGNUM ; regnum--)
 591     if (fsr.regs[regnum])
 592       {
 593         read_memory (fsr.regs[regnum], (char *)&freg_buffer, 8);
 594         write_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
 595       }
 596
 597   if (fsr.regs[IPSW_REGNUM])
 598     write_register (IPSW_REGNUM,
 599                     read_memory_integer (fsr.regs[IPSW_REGNUM], 4));
 600
 601   if (fsr.regs[SAR_REGNUM])
 602     write_register (SAR_REGNUM,
 603                     read_memory_integer (fsr.regs[SAR_REGNUM], 4));
 604
 605   if (fsr.regs[PCOQ_TAIL_REGNUM])
 606     write_register (PCOQ_TAIL_REGNUM,
 607                     read_memory_integer (fsr.regs[PCOQ_TAIL_REGNUM], 4));
 608
 609   write_register (FP_REGNUM, read_memory_integer (fp, 4));
 610
 611   if (fsr.regs[IPSW_REGNUM])    /* call dummy */
 612     write_register (SP_REGNUM, fp - 48);
 613   else
 614     write_register (SP_REGNUM, fp);
 615
 616   flush_cached_frames ();
 617   set_current_frame (create_new_frame (read_register (FP_REGNUM),
 618                                        read_pc ()));
 619 }
 620
 621 /*
 622  * After returning to a dummy on the stack, restore the instruction
 623  * queue space registers. */
 624
 625 static int
 626 restore_pc_queue (fsr)
 627      struct frame_saved_regs *fsr;
 628 {
 629   CORE_ADDR pc = read_pc ();
 630   CORE_ADDR new_pc = read_memory_integer (fsr->regs[PCOQ_HEAD_REGNUM], 4);
 631   int pid;
 632   WAITTYPE w;
 633   int insn_count;
 634
 635   /* Advance past break instruction in the call dummy. */
 636   write_register (PCOQ_HEAD_REGNUM, pc + 4);
 637   write_register (PCOQ_TAIL_REGNUM, pc + 8);
 638
 639   /*
 640    * HPUX doesn't let us set the space registers or the space
 641    * registers of the PC queue through ptrace. Boo, hiss.
 642    * Conveniently, the call dummy has this sequence of instructions
 643    * after the break:
 644    *    mtsp r21, sr0
 645    *    ble,n 0(sr0, r22)
 646    *
 647    * So, load up the registers and single step until we are in the
 648    * right place.
 649    */
 650
 651   write_register (21, read_memory_integer (fsr->regs[PCSQ_HEAD_REGNUM], 4));
 652   write_register (22, new_pc);
 653
 654   for (insn_count = 0; insn_count < 3; insn_count++)
 655     {
 656       resume (1, 0);
 657       target_wait(&w);
 658
 659       if (!WIFSTOPPED (w))
 660         {
 661           stop_signal = WTERMSIG (w);
 662           terminal_ours_for_output ();
 663           printf ("\nProgram terminated with signal %d, %s\n",
 664                   stop_signal, safe_strsignal (stop_signal));
 665           fflush (stdout);
 666           return 0;
 667         }
 668     }
 669   fetch_inferior_registers (-1);
 670   return 1;
 671 }
 672
 673 CORE_ADDR
 674 hppa_push_arguments (nargs, args, sp, struct_return, struct_addr)
 675      int nargs;
 676      value *args;
 677      CORE_ADDR sp;
 678      int struct_return;
 679      CORE_ADDR struct_addr;
 680 {
 681   /* array of arguments' offsets */
 682   int *offset = (int *)alloca(nargs * sizeof (int));
 683   int cum = 0;
 684   int i, alignment;
 685
 686   for (i = 0; i < nargs; i++)
 687     {
 688       /* Coerce chars to int & float to double if necessary */
 689       args[i] = value_arg_coerce (args[i]);
 690
 691       cum += TYPE_LENGTH (VALUE_TYPE (args[i]));
 692
 693     /* value must go at proper alignment. Assume alignment is a
 694          power of two.*/
 695       alignment = hppa_alignof (VALUE_TYPE (args[i]));
 696       if (cum % alignment)
 697         cum = (cum + alignment) & -alignment;
 698       offset[i] = -cum;
 699     }
 700   sp += max ((cum + 7) & -8, 16);
 701
 702   for (i = 0; i < nargs; i++)
 703     write_memory (sp + offset[i], VALUE_CONTENTS (args[i]),
 704                   TYPE_LENGTH (VALUE_TYPE (args[i])));
 705
 706   if (struct_return)
 707     write_register (28, struct_addr);
 708   return sp + 32;
 709 }
 710
 711 /*
 712  * Insert the specified number of args and function address
 713  * into a call sequence of the above form stored at DUMMYNAME.
 714  *
 715  * On the hppa we need to call the stack dummy through $$dyncall.
 716  * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
 717  * real_pc, which is the location where gdb should start up the
 718  * inferior to do the function call.
 719  */
 720
 721 CORE_ADDR
 722 hppa_fix_call_dummy (dummy, pc, fun, nargs, args, type, gcc_p)
 723      REGISTER_TYPE *dummy;
 724      CORE_ADDR pc;
 725      CORE_ADDR fun;
 726      int nargs;
 727      value *args;
 728      struct type *type;
 729      int gcc_p;
 730 {
 731   CORE_ADDR dyncall_addr, sr4export_addr;
 732   struct minimal_symbol *msymbol;
 733
 734   msymbol = lookup_minimal_symbol ("$$dyncall", (struct objfile *) NULL);
 735   if (msymbol == NULL)
 736     error ("Can't find an address for $$dyncall trampoline");
 737
 738   dyncall_addr = SYMBOL_VALUE_ADDRESS (msymbol);
 739
 740   msymbol = lookup_minimal_symbol ("_sr4export", (struct objfile *) NULL);
 741   if (msymbol == NULL)
 742     error ("Can't find an address for _sr4export trampoline");
 743
 744   sr4export_addr = SYMBOL_VALUE_ADDRESS (msymbol);
 745
 746   dummy[9] = deposit_21 (fun >> 11, dummy[9]);
 747   dummy[10] = deposit_14 (fun & MASK_11, dummy[10]);
 748   dummy[12] = deposit_21 (sr4export_addr >> 11, dummy[12]);
 749   dummy[13] = deposit_14 (sr4export_addr & MASK_11, dummy[13]);
 750
 751   write_register (22, pc);
 752
 753   return dyncall_addr;
 754 }
 755
 756 /* return the alignment of a type in bytes. Structures have the maximum
 757    alignment required by their fields. */
 758
 759 static int
 760 hppa_alignof (arg)
 761      struct type *arg;
 762 {
 763   int max_align, align, i;
 764   switch (TYPE_CODE (arg))
 765     {
 766     case TYPE_CODE_PTR:
 767     case TYPE_CODE_INT:
 768     case TYPE_CODE_FLT:
 769       return TYPE_LENGTH (arg);
 770     case TYPE_CODE_ARRAY:
 771       return hppa_alignof (TYPE_FIELD_TYPE (arg, 0));
 772     case TYPE_CODE_STRUCT:
 773     case TYPE_CODE_UNION:
 774       max_align = 2;
 775       for (i = 0; i < TYPE_NFIELDS (arg); i++)
 776         {
 777           /* Bit fields have no real alignment. */
 778           if (!TYPE_FIELD_BITPOS (arg, i))
 779             {
 780               align = hppa_alignof (TYPE_FIELD_TYPE (arg, i));
 781               max_align = max (max_align, align);
 782             }
 783         }
 784       return max_align;
 785     default:
 786       return 4;
 787     }
 788 }
 789
 790 /* Print the register regnum, or all registers if regnum is -1 */
 791
 792 pa_do_registers_info (regnum, fpregs)
 793      int regnum;
 794      int fpregs;
 795 {
 796   char raw_regs [REGISTER_BYTES];
 797   int i;
 798
 799   for (i = 0; i < NUM_REGS; i++)
 800     read_relative_register_raw_bytes (i, raw_regs + REGISTER_BYTE (i));
 801   if (regnum == -1)
 802     pa_print_registers (raw_regs, regnum, fpregs);
 803   else if (regnum < FP0_REGNUM)
 804     printf ("%s %x\n", reg_names[regnum], *(long *)(raw_regs +
 805                                                     REGISTER_BYTE (regnum)));
 806   else
 807     pa_print_fp_reg (regnum);
 808 }
 809
 810 pa_print_registers (raw_regs, regnum, fpregs)
 811      char *raw_regs;
 812      int regnum;
 813      int fpregs;
 814 {
 815   int i;
 816
 817   for (i = 0; i < 18; i++)
 818     printf ("%8.8s: %8x  %8.8s: %8x  %8.8s: %8x  %8.8s: %8x\n",
 819             reg_names[i],
 820             *(int *)(raw_regs + REGISTER_BYTE (i)),
 821             reg_names[i + 18],
 822             *(int *)(raw_regs + REGISTER_BYTE (i + 18)),
 823             reg_names[i + 36],
 824             *(int *)(raw_regs + REGISTER_BYTE (i + 36)),
 825             reg_names[i + 54],
 826             *(int *)(raw_regs + REGISTER_BYTE (i + 54)));
 827
 828   if (fpregs)
 829     for (i = 72; i < NUM_REGS; i++)
 830       pa_print_fp_reg (i);
 831 }
 832
 833 pa_print_fp_reg (i)
 834      int i;
 835 {
 836   unsigned char raw_buffer[MAX_REGISTER_RAW_SIZE];
 837   unsigned char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
 838   REGISTER_TYPE val;
 839
 840   /* Get the data in raw format, then convert also to virtual format.  */
 841   read_relative_register_raw_bytes (i, raw_buffer);
 842   REGISTER_CONVERT_TO_VIRTUAL (i, raw_buffer, virtual_buffer);
 843
 844   fputs_filtered (reg_names[i], stdout);
 845   print_spaces_filtered (15 - strlen (reg_names[i]), stdout);
 846
 847   val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, stdout, 0,
 848              1, 0, Val_pretty_default);
 849   printf_filtered ("\n");
 850 }
 851
 852 /* Function calls that pass into a new compilation unit must pass through a
 853    small piece of code that does long format (`external' in HPPA parlance)
 854    jumps.  We figure out where the trampoline is going to end up, and return
 855    the PC of the final destination.  If we aren't in a trampoline, we just
 856    return NULL.
 857
 858    For computed calls, we just extract the new PC from r22.  */
 859
 860 CORE_ADDR
 861 skip_trampoline_code (pc, name)
 862      CORE_ADDR pc;
 863      char *name;
 864 {
 865   long inst0, inst1;
 866   static CORE_ADDR dyncall = 0;
 867   struct minimal_symbol *msym;
 868
 869 /* FIXME XXX - dyncall must be initialized whenever we get a new exec file */
 870
 871   if (!dyncall)
 872     {
 873       msym = lookup_minimal_symbol ("$$dyncall", NULL);
 874       if (msym)
 875         dyncall = SYMBOL_VALUE_ADDRESS (msym);
 876       else
 877         dyncall = -1;
 878     }
 879
 880   if (pc == dyncall)
 881     return (CORE_ADDR)(read_register (22) & ~0x3);
 882
 883   inst0 = read_memory_integer (pc, 4);
 884   inst1 = read_memory_integer (pc+4, 4);
 885
 886   if (   (inst0 & 0xffe00000) == 0x20200000 /* ldil xxx, r1 */
 887       && (inst1 & 0xffe0e002) == 0xe0202002) /* be,n yyy(sr4, r1) */
 888     pc = extract_21 (inst0) + extract_17 (inst1);
 889   else
 890     pc = (CORE_ADDR)NULL;
 891
 892   return pc;
 893 }
 894
 895 /* Advance PC across any function entry prologue instructions
 896    to reach some "real" code.  */
 897
 898 /* skip (stw rp, -20(0,sp)); copy 4,1; copy sp, 4; stwm 1,framesize(sp)
 899    for gcc, or (stw rp, -20(0,sp); stwm 1, framesize(sp) for hcc */
 900
 901 CORE_ADDR
 902 skip_prologue(pc)
 903      CORE_ADDR pc;
 904 {
 905   char buf[4];
 906   unsigned long inst;
 907   int status;
 908
 909   status = target_read_memory (pc, buf, 4);
 910   inst = extract_unsigned_integer (buf, 4);
 911   if (status != 0)
 912     return pc;
 913
 914   if (inst == 0x6BC23FD9)       /* stw rp,-20(sp) */
 915     {
 916       if (read_memory_integer (pc + 4, 4) == 0x8040241) /* copy r4,r1 */
 917         pc += 16;
 918       else if ((read_memory_integer (pc + 4, 4) & ~MASK_14) == 0x68810000) /* stw r1,(r4) */
 919         pc += 8;
 920     }
 921   else if (read_memory_integer (pc, 4) == 0x8040241) /* copy r4,r1 */
 922     pc += 12;
 923   else if ((read_memory_integer (pc, 4) & ~MASK_14) == 0x68810000) /* stw r1,(r4) */
 924     pc += 4;
 925
 926   return pc;
 927 }
 928
 929 static void
 930 unwind_command (exp, from_tty)
 931      char *exp;
 932      int from_tty;
 933 {
 934   CORE_ADDR address;
 935   union
 936     {
 937       int *foo;
 938       struct unwind_table_entry *u;
 939     } xxx;
 940
 941   /* If we have an expression, evaluate it and use it as the address.  */
 942
 943   if (exp != 0 && *exp != 0)
 944     address = parse_and_eval_address (exp);
 945   else
 946     return;
 947
 948   xxx.u = find_unwind_entry (address);
 949
 950   if (!xxx.u)
 951     {
 952       printf ("Can't find unwind table entry for PC 0x%x\n", address);
 953       return;
 954     }
 955
 956   printf ("%08x\n%08X\n%08X\n%08X\n", xxx.foo[0], xxx.foo[1], xxx.foo[2],
 957           xxx.foo[3]);
 958 }
 959
 960 void
 961 _initialize_hppa_tdep ()
 962 {
 963   add_com ("unwind", class_obscure, unwind_command, "Print unwind info\n");
 964   add_show_from_set
 965     (add_set_cmd ("use_unwind", class_obscure, var_boolean,
 966                   (char *)&use_unwind,
 967                   "Set the usage of unwind info", &setlist),
 968      &showlist);
 969 }