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 /* Called when no unwind descriptor was found for PC.  Returns 1 if it
 300    appears that PC is in a linker stub.  */
 301 static int pc_in_linker_stub PARAMS ((CORE_ADDR));
 302
 303 static int
 304 pc_in_linker_stub (pc)
 305      CORE_ADDR pc;
 306 {
 307   int found_magic_instruction = 0;
 308   int i;
 309
 310   /* We are looking for something like
 311
 312      ; $$dyncall jams RP into this special spot in the frame (RP')
 313      ; before calling the "call stub"
 314      ldw     -18(sp),rp
 315
 316      ldsid   (rp),r1         ; Get space associated with RP into r1
 317      mtsp    r1,sp           ; Move it into space register 0
 318      be,n    0(sr0),rp)      ; back to your regularly scheduled program
 319      */
 320
 321   /* Maximum known linker stub size is 4 instructions.  Search forward
 322      from the given PC, then backward.  */
 323   for (i = 0; i < 4; i++)
 324     {
 325       /* If we hit something with an unwind, stop searching this direction.
 326
 327       if (find_unwind_entry (pc + i * 4) != 0)
 328         break;
 329
 330       /* Check for ldsid (rp),r1 which is the magic instruction for a
 331          return from a cross-space function call.  */
 332       if (read_memory_integer (pc + i * 4, 4) == 0x004010a1)
 333         {
 334           found_magic_instruction = 1;
 335           break;
 336         }
 337       /* Add code to handle long call/branch and argument relocation stubs
 338          here.  */
 339     }
 340
 341   if (found_magic_instruction != 0)
 342     return 1;
 343
 344   /* Now look backward.  */
 345   for (i = 0; i < 4; i++)
 346     {
 347       /* If we hit something with an unwind, stop searching this direction.
 348
 349       if (find_unwind_entry (pc - i * 4) != 0)
 350         break;
 351
 352       /* Check for ldsid (rp),r1 which is the magic instruction for a
 353          return from a cross-space function call.  */
 354       if (read_memory_integer (pc - i * 4, 4) == 0x004010a1)
 355         {
 356           found_magic_instruction = 1;
 357           break;
 358         }
 359       /* Add code to handle long call/branch and argument relocation stubs
 360          here.  */
 361     }
 362   return found_magic_instruction;
 363 }
 364
 365 static int
 366 find_return_regnum(pc)
 367      CORE_ADDR pc;
 368 {
 369   struct unwind_table_entry *u;
 370
 371   u = find_unwind_entry (pc);
 372
 373   if (!u)
 374     return RP_REGNUM;
 375
 376   if (u->Millicode)
 377     return 31;
 378
 379   return RP_REGNUM;
 380 }
 381
 382 /* Return size of frame, or -1 if we should use a frame pointer.  */
 383 int
 384 find_proc_framesize(pc)
 385      CORE_ADDR pc;
 386 {
 387   struct unwind_table_entry *u;
 388
 389   if (!use_unwind)
 390     return -1;
 391
 392   u = find_unwind_entry (pc);
 393
 394   if (!u)
 395     {
 396       if (pc_in_linker_stub (pc))
 397         /* Linker stubs have a zero size frame.  */
 398         return 0;
 399       else
 400         return -1;
 401     }
 402
 403   if (u->Save_SP)
 404     /* If this bit is set, it means there is a frame pointer and we should
 405        use it.  */
 406     return -1;
 407
 408   return u->Total_frame_size << 3;
 409 }
 410
 411 /* Return offset from sp at which rp is saved, or 0 if not saved.  */
 412 static int rp_saved PARAMS ((CORE_ADDR));
 413
 414 static int
 415 rp_saved (pc)
 416      CORE_ADDR pc;
 417 {
 418   struct unwind_table_entry *u;
 419
 420   u = find_unwind_entry (pc);
 421
 422   if (!u)
 423     {
 424       if (pc_in_linker_stub (pc))
 425         /* This is the so-called RP'.  */
 426         return -24;
 427       else
 428         return 0;
 429     }
 430
 431   if (u->Save_RP)
 432     return -20;
 433   else
 434     return 0;
 435 }
 436 \f
 437 int
 438 frameless_function_invocation (frame)
 439      FRAME frame;
 440 {
 441
 442   if (use_unwind)
 443     {
 444       struct unwind_table_entry *u;
 445
 446       u = find_unwind_entry (frame->pc);
 447
 448       if (u == 0)
 449         return 0;
 450
 451       return (u->Total_frame_size == 0);
 452     }
 453   else
 454     return frameless_look_for_prologue (frame);
 455 }
 456
 457 CORE_ADDR
 458 saved_pc_after_call (frame)
 459      FRAME frame;
 460 {
 461   int ret_regnum;
 462
 463   ret_regnum = find_return_regnum (get_frame_pc (frame));
 464
 465   return read_register (ret_regnum) & ~0x3;
 466 }
 467 \f
 468 CORE_ADDR
 469 frame_saved_pc (frame)
 470      FRAME frame;
 471 {
 472   CORE_ADDR pc = get_frame_pc (frame);
 473
 474   if (frameless_function_invocation (frame))
 475     {
 476       int ret_regnum;
 477
 478       ret_regnum = find_return_regnum (pc);
 479
 480       return read_register (ret_regnum) & ~0x3;
 481     }
 482   else
 483     {
 484       int rp_offset = rp_saved (pc);
 485
 486       if (rp_offset == 0)
 487         return read_register (RP_REGNUM) & ~0x3;
 488       else
 489         return read_memory_integer (frame->frame + rp_offset, 4) & ~0x3;
 490     }
 491 }
 492 \f
 493 /* We need to correct the PC and the FP for the outermost frame when we are
 494    in a system call.  */
 495
 496 void
 497 init_extra_frame_info (fromleaf, frame)
 498      int fromleaf;
 499      struct frame_info *frame;
 500 {
 501   int flags;
 502   int framesize;
 503
 504   if (frame->next)              /* Only do this for outermost frame */
 505     return;
 506
 507   flags = read_register (FLAGS_REGNUM);
 508   if (flags & 2)        /* In system call? */
 509     frame->pc = read_register (31) & ~0x3;
 510
 511   /* The outermost frame is always derived from PC-framesize */
 512   framesize = find_proc_framesize(frame->pc);
 513   if (framesize == -1)
 514     frame->frame = read_register (FP_REGNUM);
 515   else
 516     frame->frame = read_register (SP_REGNUM) - framesize;
 517
 518   if (!frameless_function_invocation (frame)) /* Frameless? */
 519     return;                                 /* No, quit now */
 520
 521   /* For frameless functions, we need to look at the caller's frame */
 522   framesize = find_proc_framesize(FRAME_SAVED_PC(frame));
 523   if (framesize != -1)
 524     frame->frame -= framesize;
 525 }
 526 \f
 527 FRAME_ADDR
 528 frame_chain (frame)
 529      struct frame_info *frame;
 530 {
 531   int framesize;
 532
 533   framesize = find_proc_framesize(FRAME_SAVED_PC(frame));
 534
 535   if (framesize != -1)
 536     return frame->frame - framesize;
 537
 538   return read_memory_integer (frame->frame, 4);
 539 }
 540 \f
 541 /* To see if a frame chain is valid, see if the caller looks like it
 542    was compiled with gcc. */
 543
 544 int
 545 frame_chain_valid (chain, thisframe)
 546      FRAME_ADDR chain;
 547      FRAME thisframe;
 548 {
 549   struct minimal_symbol *msym;
 550
 551   if (!chain)
 552     return 0;
 553
 554   if (use_unwind)
 555     {
 556
 557       struct unwind_table_entry *u;
 558
 559       u = find_unwind_entry (thisframe->pc);
 560
 561       if (u == NULL)
 562         /* FIXME, we should probably fall back to some other technique,
 563            if we want to deal gracefully with stripped executables or others
 564            without unwind info.  */
 565         return 0;
 566
 567       if (u->Save_SP || u->Total_frame_size)
 568         return 1;
 569
 570       if (pc_in_linker_stub (thisframe->pc))
 571         return 1;
 572
 573       return 0;
 574     }
 575   else
 576     {
 577       msym = lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe));
 578
 579       if (msym
 580           && (strcmp (SYMBOL_NAME (msym), "_start") == 0))
 581         return 0;
 582       else
 583         return 1;
 584     }
 585 }
 586
 587 /*
 588  * These functions deal with saving and restoring register state
 589  * around a function call in the inferior. They keep the stack
 590  * double-word aligned; eventually, on an hp700, the stack will have
 591  * to be aligned to a 64-byte boundary.
 592  */
 593
 594 int
 595 push_dummy_frame ()
 596 {
 597   register CORE_ADDR sp;
 598   register int regnum;
 599   int int_buffer;
 600   double freg_buffer;
 601
 602   /* Space for "arguments"; the RP goes in here. */
 603   sp = read_register (SP_REGNUM) + 48;
 604   int_buffer = read_register (RP_REGNUM) | 0x3;
 605   write_memory (sp - 20, (char *)&int_buffer, 4);
 606
 607   int_buffer = read_register (FP_REGNUM);
 608   write_memory (sp, (char *)&int_buffer, 4);
 609
 610   write_register (FP_REGNUM, sp);
 611
 612   sp += 8;
 613
 614   for (regnum = 1; regnum < 32; regnum++)
 615     if (regnum != RP_REGNUM && regnum != FP_REGNUM)
 616       sp = push_word (sp, read_register (regnum));
 617
 618   sp += 4;
 619
 620   for (regnum = FP0_REGNUM; regnum < NUM_REGS; regnum++)
 621     {
 622       read_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
 623       sp = push_bytes (sp, (char *)&freg_buffer, 8);
 624     }
 625   sp = push_word (sp, read_register (IPSW_REGNUM));
 626   sp = push_word (sp, read_register (SAR_REGNUM));
 627   sp = push_word (sp, read_register (PCOQ_HEAD_REGNUM));
 628   sp = push_word (sp, read_register (PCSQ_HEAD_REGNUM));
 629   sp = push_word (sp, read_register (PCOQ_TAIL_REGNUM));
 630   sp = push_word (sp, read_register (PCSQ_TAIL_REGNUM));
 631   write_register (SP_REGNUM, sp);
 632 }
 633
 634 find_dummy_frame_regs (frame, frame_saved_regs)
 635      struct frame_info *frame;
 636      struct frame_saved_regs *frame_saved_regs;
 637 {
 638   CORE_ADDR fp = frame->frame;
 639   int i;
 640
 641   frame_saved_regs->regs[RP_REGNUM] = fp - 20 & ~0x3;
 642   frame_saved_regs->regs[FP_REGNUM] = fp;
 643   frame_saved_regs->regs[1] = fp + 8;
 644
 645   for (fp += 12, i = 3; i < 32; i++)
 646     {
 647       if (i != FP_REGNUM)
 648         {
 649           frame_saved_regs->regs[i] = fp;
 650           fp += 4;
 651         }
 652     }
 653
 654   fp += 4;
 655   for (i = FP0_REGNUM; i < NUM_REGS; i++, fp += 8)
 656     frame_saved_regs->regs[i] = fp;
 657
 658   frame_saved_regs->regs[IPSW_REGNUM] = fp;
 659   frame_saved_regs->regs[SAR_REGNUM] = fp + 4;
 660   frame_saved_regs->regs[PCOQ_HEAD_REGNUM] = fp + 8;
 661   frame_saved_regs->regs[PCSQ_HEAD_REGNUM] = fp + 12;
 662   frame_saved_regs->regs[PCOQ_TAIL_REGNUM] = fp + 16;
 663   frame_saved_regs->regs[PCSQ_TAIL_REGNUM] = fp + 20;
 664 }
 665
 666 int
 667 hppa_pop_frame ()
 668 {
 669   register FRAME frame = get_current_frame ();
 670   register CORE_ADDR fp;
 671   register int regnum;
 672   struct frame_saved_regs fsr;
 673   struct frame_info *fi;
 674   double freg_buffer;
 675
 676   fi = get_frame_info (frame);
 677   fp = fi->frame;
 678   get_frame_saved_regs (fi, &fsr);
 679
 680   if (fsr.regs[IPSW_REGNUM])    /* Restoring a call dummy frame */
 681     restore_pc_queue (&fsr);
 682
 683   for (regnum = 31; regnum > 0; regnum--)
 684     if (fsr.regs[regnum])
 685       write_register (regnum, read_memory_integer (fsr.regs[regnum], 4));
 686
 687   for (regnum = NUM_REGS - 1; regnum >= FP0_REGNUM ; regnum--)
 688     if (fsr.regs[regnum])
 689       {
 690         read_memory (fsr.regs[regnum], (char *)&freg_buffer, 8);
 691         write_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
 692       }
 693
 694   if (fsr.regs[IPSW_REGNUM])
 695     write_register (IPSW_REGNUM,
 696                     read_memory_integer (fsr.regs[IPSW_REGNUM], 4));
 697
 698   if (fsr.regs[SAR_REGNUM])
 699     write_register (SAR_REGNUM,
 700                     read_memory_integer (fsr.regs[SAR_REGNUM], 4));
 701
 702   if (fsr.regs[PCOQ_TAIL_REGNUM])
 703     write_register (PCOQ_TAIL_REGNUM,
 704                     read_memory_integer (fsr.regs[PCOQ_TAIL_REGNUM], 4));
 705
 706   write_register (FP_REGNUM, read_memory_integer (fp, 4));
 707
 708   if (fsr.regs[IPSW_REGNUM])    /* call dummy */
 709     write_register (SP_REGNUM, fp - 48);
 710   else
 711     write_register (SP_REGNUM, fp);
 712
 713   flush_cached_frames ();
 714   set_current_frame (create_new_frame (read_register (FP_REGNUM),
 715                                        read_pc ()));
 716 }
 717
 718 /*
 719  * After returning to a dummy on the stack, restore the instruction
 720  * queue space registers. */
 721
 722 static int
 723 restore_pc_queue (fsr)
 724      struct frame_saved_regs *fsr;
 725 {
 726   CORE_ADDR pc = read_pc ();
 727   CORE_ADDR new_pc = read_memory_integer (fsr->regs[PCOQ_HEAD_REGNUM], 4);
 728   int pid;
 729   WAITTYPE w;
 730   int insn_count;
 731
 732   /* Advance past break instruction in the call dummy. */
 733   write_register (PCOQ_HEAD_REGNUM, pc + 4);
 734   write_register (PCOQ_TAIL_REGNUM, pc + 8);
 735
 736   /*
 737    * HPUX doesn't let us set the space registers or the space
 738    * registers of the PC queue through ptrace. Boo, hiss.
 739    * Conveniently, the call dummy has this sequence of instructions
 740    * after the break:
 741    *    mtsp r21, sr0
 742    *    ble,n 0(sr0, r22)
 743    *
 744    * So, load up the registers and single step until we are in the
 745    * right place.
 746    */
 747
 748   write_register (21, read_memory_integer (fsr->regs[PCSQ_HEAD_REGNUM], 4));
 749   write_register (22, new_pc);
 750
 751   for (insn_count = 0; insn_count < 3; insn_count++)
 752     {
 753       resume (1, 0);
 754       target_wait(&w);
 755
 756       if (!WIFSTOPPED (w))
 757         {
 758           stop_signal = WTERMSIG (w);
 759           terminal_ours_for_output ();
 760           printf ("\nProgram terminated with signal %d, %s\n",
 761                   stop_signal, safe_strsignal (stop_signal));
 762           fflush (stdout);
 763           return 0;
 764         }
 765     }
 766   fetch_inferior_registers (-1);
 767   return 1;
 768 }
 769
 770 CORE_ADDR
 771 hppa_push_arguments (nargs, args, sp, struct_return, struct_addr)
 772      int nargs;
 773      value *args;
 774      CORE_ADDR sp;
 775      int struct_return;
 776      CORE_ADDR struct_addr;
 777 {
 778   /* array of arguments' offsets */
 779   int *offset = (int *)alloca(nargs * sizeof (int));
 780   int cum = 0;
 781   int i, alignment;
 782
 783   for (i = 0; i < nargs; i++)
 784     {
 785       /* Coerce chars to int & float to double if necessary */
 786       args[i] = value_arg_coerce (args[i]);
 787
 788       cum += TYPE_LENGTH (VALUE_TYPE (args[i]));
 789
 790     /* value must go at proper alignment. Assume alignment is a
 791          power of two.*/
 792       alignment = hppa_alignof (VALUE_TYPE (args[i]));
 793       if (cum % alignment)
 794         cum = (cum + alignment) & -alignment;
 795       offset[i] = -cum;
 796     }
 797   sp += max ((cum + 7) & -8, 16);
 798
 799   for (i = 0; i < nargs; i++)
 800     write_memory (sp + offset[i], VALUE_CONTENTS (args[i]),
 801                   TYPE_LENGTH (VALUE_TYPE (args[i])));
 802
 803   if (struct_return)
 804     write_register (28, struct_addr);
 805   return sp + 32;
 806 }
 807
 808 /*
 809  * Insert the specified number of args and function address
 810  * into a call sequence of the above form stored at DUMMYNAME.
 811  *
 812  * On the hppa we need to call the stack dummy through $$dyncall.
 813  * Therefore our version of FIX_CALL_DUMMY takes an extra argument,
 814  * real_pc, which is the location where gdb should start up the
 815  * inferior to do the function call.
 816  */
 817
 818 CORE_ADDR
 819 hppa_fix_call_dummy (dummy, pc, fun, nargs, args, type, gcc_p)
 820      REGISTER_TYPE *dummy;
 821      CORE_ADDR pc;
 822      CORE_ADDR fun;
 823      int nargs;
 824      value *args;
 825      struct type *type;
 826      int gcc_p;
 827 {
 828   CORE_ADDR dyncall_addr, sr4export_addr;
 829   struct minimal_symbol *msymbol;
 830
 831   msymbol = lookup_minimal_symbol ("$$dyncall", (struct objfile *) NULL);
 832   if (msymbol == NULL)
 833     error ("Can't find an address for $$dyncall trampoline");
 834
 835   dyncall_addr = SYMBOL_VALUE_ADDRESS (msymbol);
 836
 837   msymbol = lookup_minimal_symbol ("_sr4export", (struct objfile *) NULL);
 838   if (msymbol == NULL)
 839     error ("Can't find an address for _sr4export trampoline");
 840
 841   sr4export_addr = SYMBOL_VALUE_ADDRESS (msymbol);
 842
 843   dummy[9] = deposit_21 (fun >> 11, dummy[9]);
 844   dummy[10] = deposit_14 (fun & MASK_11, dummy[10]);
 845   dummy[12] = deposit_21 (sr4export_addr >> 11, dummy[12]);
 846   dummy[13] = deposit_14 (sr4export_addr & MASK_11, dummy[13]);
 847
 848   write_register (22, pc);
 849
 850   return dyncall_addr;
 851 }
 852
 853 /* return the alignment of a type in bytes. Structures have the maximum
 854    alignment required by their fields. */
 855
 856 static int
 857 hppa_alignof (arg)
 858      struct type *arg;
 859 {
 860   int max_align, align, i;
 861   switch (TYPE_CODE (arg))
 862     {
 863     case TYPE_CODE_PTR:
 864     case TYPE_CODE_INT:
 865     case TYPE_CODE_FLT:
 866       return TYPE_LENGTH (arg);
 867     case TYPE_CODE_ARRAY:
 868       return hppa_alignof (TYPE_FIELD_TYPE (arg, 0));
 869     case TYPE_CODE_STRUCT:
 870     case TYPE_CODE_UNION:
 871       max_align = 2;
 872       for (i = 0; i < TYPE_NFIELDS (arg); i++)
 873         {
 874           /* Bit fields have no real alignment. */
 875           if (!TYPE_FIELD_BITPOS (arg, i))
 876             {
 877               align = hppa_alignof (TYPE_FIELD_TYPE (arg, i));
 878               max_align = max (max_align, align);
 879             }
 880         }
 881       return max_align;
 882     default:
 883       return 4;
 884     }
 885 }
 886
 887 /* Print the register regnum, or all registers if regnum is -1 */
 888
 889 pa_do_registers_info (regnum, fpregs)
 890      int regnum;
 891      int fpregs;
 892 {
 893   char raw_regs [REGISTER_BYTES];
 894   int i;
 895
 896   for (i = 0; i < NUM_REGS; i++)
 897     read_relative_register_raw_bytes (i, raw_regs + REGISTER_BYTE (i));
 898   if (regnum == -1)
 899     pa_print_registers (raw_regs, regnum, fpregs);
 900   else if (regnum < FP0_REGNUM)
 901     printf ("%s %x\n", reg_names[regnum], *(long *)(raw_regs +
 902                                                     REGISTER_BYTE (regnum)));
 903   else
 904     pa_print_fp_reg (regnum);
 905 }
 906
 907 pa_print_registers (raw_regs, regnum, fpregs)
 908      char *raw_regs;
 909      int regnum;
 910      int fpregs;
 911 {
 912   int i;
 913
 914   for (i = 0; i < 18; i++)
 915     printf ("%8.8s: %8x  %8.8s: %8x  %8.8s: %8x  %8.8s: %8x\n",
 916             reg_names[i],
 917             *(int *)(raw_regs + REGISTER_BYTE (i)),
 918             reg_names[i + 18],
 919             *(int *)(raw_regs + REGISTER_BYTE (i + 18)),
 920             reg_names[i + 36],
 921             *(int *)(raw_regs + REGISTER_BYTE (i + 36)),
 922             reg_names[i + 54],
 923             *(int *)(raw_regs + REGISTER_BYTE (i + 54)));
 924
 925   if (fpregs)
 926     for (i = 72; i < NUM_REGS; i++)
 927       pa_print_fp_reg (i);
 928 }
 929
 930 pa_print_fp_reg (i)
 931      int i;
 932 {
 933   unsigned char raw_buffer[MAX_REGISTER_RAW_SIZE];
 934   unsigned char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
 935   REGISTER_TYPE val;
 936
 937   /* Get the data in raw format, then convert also to virtual format.  */
 938   read_relative_register_raw_bytes (i, raw_buffer);
 939   REGISTER_CONVERT_TO_VIRTUAL (i, raw_buffer, virtual_buffer);
 940
 941   fputs_filtered (reg_names[i], stdout);
 942   print_spaces_filtered (15 - strlen (reg_names[i]), stdout);
 943
 944   val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, stdout, 0,
 945              1, 0, Val_pretty_default);
 946   printf_filtered ("\n");
 947 }
 948
 949 /* Function calls that pass into a new compilation unit must pass through a
 950    small piece of code that does long format (`external' in HPPA parlance)
 951    jumps.  We figure out where the trampoline is going to end up, and return
 952    the PC of the final destination.  If we aren't in a trampoline, we just
 953    return NULL.
 954
 955    For computed calls, we just extract the new PC from r22.  */
 956
 957 CORE_ADDR
 958 skip_trampoline_code (pc, name)
 959      CORE_ADDR pc;
 960      char *name;
 961 {
 962   long inst0, inst1;
 963   static CORE_ADDR dyncall = 0;
 964   struct minimal_symbol *msym;
 965
 966 /* FIXME XXX - dyncall must be initialized whenever we get a new exec file */
 967
 968   if (!dyncall)
 969     {
 970       msym = lookup_minimal_symbol ("$$dyncall", NULL);
 971       if (msym)
 972         dyncall = SYMBOL_VALUE_ADDRESS (msym);
 973       else
 974         dyncall = -1;
 975     }
 976
 977   if (pc == dyncall)
 978     return (CORE_ADDR)(read_register (22) & ~0x3);
 979
 980   inst0 = read_memory_integer (pc, 4);
 981   inst1 = read_memory_integer (pc+4, 4);
 982
 983   if (   (inst0 & 0xffe00000) == 0x20200000 /* ldil xxx, r1 */
 984       && (inst1 & 0xffe0e002) == 0xe0202002) /* be,n yyy(sr4, r1) */
 985     pc = extract_21 (inst0) + extract_17 (inst1);
 986   else
 987     pc = (CORE_ADDR)NULL;
 988
 989   return pc;
 990 }
 991
 992 /* Advance PC across any function entry prologue instructions
 993    to reach some "real" code.  */
 994
 995 /* skip (stw rp, -20(0,sp)); copy 4,1; copy sp, 4; stwm 1,framesize(sp)
 996    for gcc, or (stw rp, -20(0,sp); stwm 1, framesize(sp) for hcc */
 997
 998 CORE_ADDR
 999 skip_prologue(pc)
1000      CORE_ADDR pc;
1001 {
1002   char buf[4];
1003   unsigned long inst;
1004   int status;
1005
1006   status = target_read_memory (pc, buf, 4);
1007   inst = extract_unsigned_integer (buf, 4);
1008   if (status != 0)
1009     return pc;
1010
1011   if (inst == 0x6BC23FD9)       /* stw rp,-20(sp) */
1012     {
1013       if (read_memory_integer (pc + 4, 4) == 0x8040241) /* copy r4,r1 */
1014         pc += 16;
1015       else if ((read_memory_integer (pc + 4, 4) & ~MASK_14) == 0x68810000) /* stw r1,(r4) */
1016         pc += 8;
1017     }
1018   else if (read_memory_integer (pc, 4) == 0x8040241) /* copy r4,r1 */
1019     pc += 12;
1020   else if ((read_memory_integer (pc, 4) & ~MASK_14) == 0x68810000) /* stw r1,(r4) */
1021     pc += 4;
1022
1023   return pc;
1024 }
1025
1026 static void
1027 unwind_command (exp, from_tty)
1028      char *exp;
1029      int from_tty;
1030 {
1031   CORE_ADDR address;
1032   union
1033     {
1034       int *foo;
1035       struct unwind_table_entry *u;
1036     } xxx;
1037
1038   /* If we have an expression, evaluate it and use it as the address.  */
1039
1040   if (exp != 0 && *exp != 0)
1041     address = parse_and_eval_address (exp);
1042   else
1043     return;
1044
1045   xxx.u = find_unwind_entry (address);
1046
1047   if (!xxx.u)
1048     {
1049       printf ("Can't find unwind table entry for PC 0x%x\n", address);
1050       return;
1051     }
1052
1053   printf ("%08x\n%08X\n%08X\n%08X\n", xxx.foo[0], xxx.foo[1], xxx.foo[2],
1054           xxx.foo[3]);
1055 }
1056
1057 void
1058 _initialize_hppa_tdep ()
1059 {
1060   add_com ("unwind", class_obscure, unwind_command, "Print unwind info\n");
1061   add_show_from_set
1062     (add_set_cmd ("use_unwind", class_obscure, var_boolean,
1063                   (char *)&use_unwind,
1064                   "Set the usage of unwind info", &setlist),
1065      &showlist);
1066 }