gdb/score-tdep.c

   1 /* Target-dependent code for the S+core architecture, for GDB,
   2    the GNU Debugger.
   3
   4    Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6    Contributed by Qinwei (qinwei@sunnorth.com.cn)
   7    Contributed by Ching-Peng Lin (cplin@sunplus.com)
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  23
  24 #include "defs.h"
  25 #include "gdb_assert.h"
  26 #include "inferior.h"
  27 #include "symtab.h"
  28 #include "objfiles.h"
  29 #include "gdbcore.h"
  30 #include "target.h"
  31 #include "arch-utils.h"
  32 #include "regcache.h"
  33 #include "dis-asm.h"
  34 #include "frame-unwind.h"
  35 #include "frame-base.h"
  36 #include "trad-frame.h"
  37 #include "dwarf2-frame.h"
  38 #include "score-tdep.h"
  39
  40 #define G_FLD(_i,_ms,_ls)   (((_i) << (31 - (_ms))) >> (31 - (_ms) + (_ls)))
  41 #define RM_PBITS(_raw)      ((G_FLD(_raw, 31, 16) << 15) | G_FLD(_raw, 14, 0))
  42
  43 typedef struct{
  44     unsigned int v;
  45     unsigned int raw;
  46     char         is15;
  47 }inst_t;
  48
  49 struct score_frame_cache
  50 {
  51   CORE_ADDR base;
  52   CORE_ADDR fp;
  53   struct trad_frame_saved_reg *saved_regs;
  54 };
  55
  56 #if 0
  57 /* If S+core GCC will generate these instructions in the prologue:
  58
  59    lw   rx, imm1
  60    addi rx, -imm2
  61    mv!  r2, rx
  62
  63    then .pdr section is used.  */
  64
  65 #define P_SIZE          8
  66 #define PI_SYM          0
  67 #define PI_R_MSK        1
  68 #define PI_R_OFF        2
  69 #define PI_R_LEF        4
  70 #define PI_F_OFF        5
  71 #define PI_F_REG        6
  72 #define PI_RAREG        7
  73
  74 typedef struct frame_extra_info
  75 {
  76   CORE_ADDR p_frame;
  77   unsigned int pdr[P_SIZE];
  78 } extra_info_t;
  79
  80 struct obj_priv
  81 {
  82   bfd_size_type size;
  83   char *contents;
  84 };
  85
  86 static bfd *the_bfd;
  87
  88 static int
  89 score_compare_pdr_entries (const void *a, const void *b)
  90 {
  91   CORE_ADDR lhs = bfd_get_32 (the_bfd, (bfd_byte *) a);
  92   CORE_ADDR rhs = bfd_get_32 (the_bfd, (bfd_byte *) b);
  93   if (lhs < rhs)
  94     return -1;
  95   else if (lhs == rhs)
  96     return 0;
  97   else
  98     return 1;
  99 }
 100
 101 static void
 102 score_analyze_pdr_section (CORE_ADDR startaddr, CORE_ADDR pc,
 103                            struct frame_info *next_frame,
 104                            struct score_frame_cache *this_cache)
 105 {
 106   struct symbol *sym;
 107   struct obj_section *sec;
 108   extra_info_t *fci_ext;
 109   CORE_ADDR leaf_ra_stack_addr = -1;
 110
 111   gdb_assert (startaddr <= pc);
 112   gdb_assert (this_cache != NULL);
 113
 114   fci_ext = frame_obstack_zalloc (sizeof (extra_info_t));
 115   if ((sec = find_pc_section (pc)) == NULL)
 116     {
 117       error ("Error: Can't find section in file:%s, line:%d!",
 118              __FILE__, __LINE__);
 119       return;
 120     }
 121
 122   /* Anylyze .pdr section and get coresponding fields.  */
 123   {
 124     static struct obj_priv *priv = NULL;
 125
 126     if (priv == NULL)
 127       {
 128         asection *bfdsec;
 129         priv = obstack_alloc (&sec->objfile->objfile_obstack,
 130                               sizeof (struct obj_priv));
 131         if ((bfdsec = bfd_get_section_by_name (sec->objfile->obfd, ".pdr")))
 132           {
 133             priv->size = bfd_section_size (sec->objfile->obfd, bfdsec);
 134             priv->contents = obstack_alloc (&sec->objfile->objfile_obstack,
 135                                             priv->size);
 136             bfd_get_section_contents (sec->objfile->obfd, bfdsec,
 137                                       priv->contents, 0, priv->size);
 138             the_bfd = sec->objfile->obfd;
 139             qsort (priv->contents, priv->size / 32, 32,
 140                    score_compare_pdr_entries);
 141             the_bfd = NULL;
 142           }
 143         else
 144           priv->size = 0;
 145       }
 146     if (priv->size != 0)
 147       {
 148         int low = 0, mid, high = priv->size / 32;
 149         char *ptr;
 150         do
 151           {
 152             CORE_ADDR pdr_pc;
 153             mid = (low + high) / 2;
 154             ptr = priv->contents + mid * 32;
 155             pdr_pc = bfd_get_signed_32 (sec->objfile->obfd, ptr);
 156             pdr_pc += ANOFFSET (sec->objfile->section_offsets,
 157                                 SECT_OFF_TEXT (sec->objfile));
 158             if (pdr_pc == startaddr)
 159               break;
 160             if (pdr_pc > startaddr)
 161               high = mid;
 162             else
 163               low = mid + 1;
 164           }
 165         while (low != high);
 166
 167         if (low != high)
 168           {
 169             gdb_assert (bfd_get_32 (sec->objfile->obfd, ptr) == startaddr);
 170 #define EXT_PDR(_pi)    bfd_get_32(sec->objfile->obfd, ptr+((_pi)<<2))
 171             fci_ext->pdr[PI_SYM] = EXT_PDR (PI_SYM);
 172             fci_ext->pdr[PI_R_MSK] = EXT_PDR (PI_R_MSK);
 173             fci_ext->pdr[PI_R_OFF] = EXT_PDR (PI_R_OFF);
 174             fci_ext->pdr[PI_R_LEF] = EXT_PDR (PI_R_LEF);
 175             fci_ext->pdr[PI_F_OFF] = EXT_PDR (PI_F_OFF);
 176             fci_ext->pdr[PI_F_REG] = EXT_PDR (PI_F_REG);
 177             fci_ext->pdr[PI_RAREG] = EXT_PDR (PI_RAREG);
 178 #undef EXT_PDR
 179           }
 180       }
 181   }
 182 }
 183 #endif
 184
 185 #if 0
 186 /* Open these functions if build with simulator.  */
 187
 188 int
 189 score_target_can_use_watch (int type, int cnt, int othertype)
 190 {
 191   if (strcmp (current_target.to_shortname, "sim") == 0)
 192     {
 193       return soc_gh_can_use_watch (type, cnt);
 194     }
 195   else
 196     {
 197       return (*current_target.to_can_use_hw_breakpoint) (type, cnt, othertype);
 198     }
 199 }
 200
 201 int
 202 score_stopped_by_watch (void)
 203 {
 204   if (strcmp (current_target.to_shortname, "sim") == 0)
 205     {
 206       return soc_gh_stopped_by_watch ();
 207     }
 208   else
 209     {
 210       return (*current_target.to_stopped_by_watchpoint) ();
 211     }
 212 }
 213
 214 int
 215 score_target_insert_watchpoint (CORE_ADDR addr, int len, int type)
 216 {
 217   if (strcmp (current_target.to_shortname, "sim") == 0)
 218     {
 219       return soc_gh_add_watch (addr, len, type);
 220     }
 221   else
 222     {
 223       return (*current_target.to_insert_watchpoint) (addr, len, type);
 224     }
 225 }
 226
 227 int
 228 score_target_remove_watchpoint (CORE_ADDR addr, int len, int type)
 229 {
 230   if (strcmp (current_target.to_shortname, "sim") == 0)
 231     {
 232       return soc_gh_del_watch (addr, len, type);
 233     }
 234   else
 235     {
 236       return (*current_target.to_remove_watchpoint) (addr, len, type);
 237     }
 238 }
 239
 240 int
 241 score_target_insert_hw_breakpoint (struct bp_target_info * bp_tgt)
 242 {
 243   if (strcmp (current_target.to_shortname, "sim") == 0)
 244     {
 245       return soc_gh_add_hardbp (bp_tgt->placed_address);
 246     }
 247   else
 248     {
 249       return (*current_target.to_insert_hw_breakpoint) (bp_tgt);
 250     }
 251 }
 252
 253 int
 254 score_target_remove_hw_breakpoint (struct bp_target_info * bp_tgt)
 255 {
 256   if (strcmp (current_target.to_shortname, "sim") == 0)
 257     {
 258       return soc_gh_del_hardbp (bp_tgt->placed_address);
 259     }
 260   else
 261     {
 262       return (*current_target.to_remove_hw_breakpoint) (bp_tgt);
 263     }
 264 }
 265 #endif
 266
 267 static struct type *
 268 score_register_type (struct gdbarch *gdbarch, int regnum)
 269 {
 270   gdb_assert (regnum >= 0 && regnum < SCORE_NUM_REGS);
 271   return builtin_type_uint32;
 272 }
 273
 274 static CORE_ADDR
 275 score_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
 276 {
 277   return frame_unwind_register_unsigned (next_frame, SCORE_PC_REGNUM);
 278 }
 279
 280 static CORE_ADDR
 281 score_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
 282 {
 283   return frame_unwind_register_unsigned (next_frame, SCORE_SP_REGNUM);
 284 }
 285
 286 static const char *
 287 score_register_name (struct gdbarch *gdbarch, int regnum)
 288 {
 289   const char *score_register_names[] = {
 290     "r0",  "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
 291     "r8",  "r9",  "r10", "r11", "r12", "r13", "r14", "r15",
 292     "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
 293     "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
 294
 295     "PSR",   "COND",   "ECR",    "EXCPVEC",
 296     "CCR",   "EPC",    "EMA",    "TLBLOCK",
 297     "TLBPT", "PEADDR", "TLBRPT", "PEVN",
 298     "PECTX", "LIMPFN", "LDMPFN", "PREV",
 299     "DREG",  "PC",     "DSAVE",  "COUNTER",
 300     "LDCR",  "STCR",   "CEH",    "CEL",
 301   };
 302
 303   gdb_assert (regnum >= 0 && regnum < SCORE_NUM_REGS);
 304   return score_register_names[regnum];
 305 }
 306
 307 static int
 308 score_register_sim_regno (struct gdbarch *gdbarch, int regnum)
 309 {
 310   gdb_assert (regnum >= 0 && regnum < SCORE_NUM_REGS);
 311   return regnum;
 312 }
 313
 314 static int
 315 score_print_insn (bfd_vma memaddr, struct disassemble_info *info)
 316 {
 317   if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
 318     return print_insn_big_score (memaddr, info);
 319   else
 320     return print_insn_little_score (memaddr, info);
 321 }
 322
 323 static const gdb_byte *
 324 score_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr,
 325                           int *lenptr)
 326 {
 327   gdb_byte buf[SCORE_INSTLEN] = { 0 };
 328   int ret;
 329   unsigned int raw;
 330
 331   if ((ret = target_read_memory (*pcptr & ~0x3, buf, SCORE_INSTLEN)) != 0)
 332     {
 333       error ("Error: target_read_memory in file:%s, line:%d!",
 334              __FILE__, __LINE__);
 335     }
 336   raw = extract_unsigned_integer (buf, SCORE_INSTLEN);
 337
 338   if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
 339     {
 340       if (!(raw & 0x80008000))
 341         {
 342           /* 16bits instruction.  */
 343           static gdb_byte big_breakpoint16[] = { 0x60, 0x02 };
 344           *pcptr &= ~0x1;
 345           *lenptr = sizeof (big_breakpoint16);
 346           return big_breakpoint16;
 347         }
 348       else
 349         {
 350           /* 32bits instruction.  */
 351           static gdb_byte big_breakpoint32[] = { 0x80, 0x00, 0x80, 0x06 };
 352           *pcptr &= ~0x3;
 353           *lenptr = sizeof (big_breakpoint32);
 354           return big_breakpoint32;
 355         }
 356     }
 357   else
 358     {
 359       if (!(raw & 0x80008000))
 360         {
 361           /* 16bits instruction.  */
 362           static gdb_byte little_breakpoint16[] = { 0x02, 0x60 };
 363           *pcptr &= ~0x1;
 364           *lenptr = sizeof (little_breakpoint16);
 365           return little_breakpoint16;
 366         }
 367       else
 368         {
 369           /* 32bits instruction.  */
 370           static gdb_byte little_breakpoint32[] = { 0x06, 0x80, 0x00, 0x80 };
 371           *pcptr &= ~0x3;
 372           *lenptr = sizeof (little_breakpoint32);
 373           return little_breakpoint32;
 374         }
 375     }
 376 }
 377
 378 static CORE_ADDR
 379 score_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
 380 {
 381   return align_down (addr, 16);
 382 }
 383
 384 static void
 385 score_xfer_register (struct regcache *regcache, int regnum, int length,
 386                      enum bfd_endian endian, gdb_byte *readbuf,
 387                      const gdb_byte *writebuf, int buf_offset)
 388 {
 389   int reg_offset = 0;
 390   gdb_assert (regnum >= 0 && regnum < SCORE_NUM_REGS);
 391
 392   switch (endian)
 393     {
 394     case BFD_ENDIAN_BIG:
 395       reg_offset = SCORE_REGSIZE - length;
 396       break;
 397     case BFD_ENDIAN_LITTLE:
 398       reg_offset = 0;
 399       break;
 400     case BFD_ENDIAN_UNKNOWN:
 401       reg_offset = 0;
 402       break;
 403     default:
 404       error ("Error: score_xfer_register in file:%s, line:%d!",
 405              __FILE__, __LINE__);
 406     }
 407
 408   if (readbuf != NULL)
 409     regcache_cooked_read_part (regcache, regnum, reg_offset, length,
 410                                readbuf + buf_offset);
 411   if (writebuf != NULL)
 412     regcache_cooked_write_part (regcache, regnum, reg_offset, length,
 413                                 writebuf + buf_offset);
 414 }
 415
 416 static enum return_value_convention
 417 score_return_value (struct gdbarch *gdbarch, struct type *type,
 418                     struct regcache *regcache,
 419                     gdb_byte * readbuf, const gdb_byte * writebuf)
 420 {
 421   if (TYPE_CODE (type) == TYPE_CODE_STRUCT
 422       || TYPE_CODE (type) == TYPE_CODE_UNION
 423       || TYPE_CODE (type) == TYPE_CODE_ARRAY)
 424     return RETURN_VALUE_STRUCT_CONVENTION;
 425   else
 426     {
 427       int offset;
 428       int regnum;
 429       for (offset = 0, regnum = SCORE_A0_REGNUM;
 430            offset < TYPE_LENGTH (type);
 431            offset += SCORE_REGSIZE, regnum++)
 432         {
 433           int xfer = SCORE_REGSIZE;
 434           if (offset + xfer > TYPE_LENGTH (type))
 435             xfer = TYPE_LENGTH (type) - offset;
 436           score_xfer_register (regcache, regnum, xfer,
 437                                gdbarch_byte_order (gdbarch),
 438                                readbuf, writebuf, offset);
 439         }
 440       return RETURN_VALUE_REGISTER_CONVENTION;
 441     }
 442 }
 443
 444 static struct frame_id
 445 score_unwind_dummy_id (struct gdbarch *gdbarch,
 446                        struct frame_info *next_frame)
 447 {
 448   return frame_id_build (
 449            frame_unwind_register_unsigned (next_frame, SCORE_SP_REGNUM),
 450            frame_pc_unwind (next_frame));
 451 }
 452
 453 static int
 454 score_type_needs_double_align (struct type *type)
 455 {
 456   enum type_code typecode = TYPE_CODE (type);
 457
 458   if ((typecode == TYPE_CODE_INT && TYPE_LENGTH (type) == 8)
 459       || (typecode == TYPE_CODE_FLT && TYPE_LENGTH (type) == 8))
 460     return 1;
 461   else if (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION)
 462     {
 463       int i, n;
 464
 465       n = TYPE_NFIELDS (type);
 466       for (i = 0; i < n; i++)
 467         if (score_type_needs_double_align (TYPE_FIELD_TYPE (type, i)))
 468           return 1;
 469       return 0;
 470     }
 471   return 0;
 472 }
 473
 474 static CORE_ADDR
 475 score_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
 476                        struct regcache *regcache, CORE_ADDR bp_addr,
 477                        int nargs, struct value **args, CORE_ADDR sp,
 478                        int struct_return, CORE_ADDR struct_addr)
 479 {
 480   int argnum;
 481   int argreg;
 482   int arglen = 0;
 483   CORE_ADDR stack_offset = 0;
 484   CORE_ADDR addr = 0;
 485
 486   /* Step 1, Save RA.  */
 487   regcache_cooked_write_unsigned (regcache, SCORE_RA_REGNUM, bp_addr);
 488
 489   /* Step 2, Make space on the stack for the args.  */
 490   struct_addr = align_down (struct_addr, 16);
 491   sp = align_down (sp, 16);
 492   for (argnum = 0; argnum < nargs; argnum++)
 493     arglen += align_up (TYPE_LENGTH (value_type (args[argnum])),
 494                         SCORE_REGSIZE);
 495   sp -= align_up (arglen, 16);
 496
 497   argreg = SCORE_BEGIN_ARG_REGNUM;
 498
 499   /* Step 3, Check if struct return then save the struct address to
 500      r4 and increase the stack_offset by 4.  */
 501   if (struct_return)
 502     {
 503       regcache_cooked_write_unsigned (regcache, argreg++, struct_addr);
 504       stack_offset += SCORE_REGSIZE;
 505     }
 506
 507   /* Step 4, Load arguments:
 508      If arg length is too long (> 4 bytes), then split the arg and
 509      save every parts.  */
 510   for (argnum = 0; argnum < nargs; argnum++)
 511     {
 512       struct value *arg = args[argnum];
 513       struct type *arg_type = check_typedef (value_type (arg));
 514       enum type_code typecode = TYPE_CODE (arg_type);
 515       const gdb_byte *val = value_contents (arg);
 516       int downward_offset = 0;
 517       int odd_sized_struct_p;
 518       int arg_last_part_p = 0;
 519
 520       arglen = TYPE_LENGTH (arg_type);
 521       odd_sized_struct_p = (arglen > SCORE_REGSIZE
 522                             && arglen % SCORE_REGSIZE != 0);
 523
 524       /* If a arg should be aligned to 8 bytes (long long or double),
 525          the value should be put to even register numbers.  */
 526       if (score_type_needs_double_align (arg_type))
 527         {
 528           if (argreg & 1)
 529             argreg++;
 530         }
 531
 532       /* If sizeof a block < SCORE_REGSIZE, then Score GCC will chose
 533          the default "downward"/"upward" method:
 534
 535          Example:
 536
 537          struct struc
 538          {
 539            char a; char b; char c;
 540          } s = {'a', 'b', 'c'};
 541
 542          Big endian:    s = {X, 'a', 'b', 'c'}
 543          Little endian: s = {'a', 'b', 'c', X}
 544
 545          Where X is a hole.  */
 546
 547       if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG
 548           && (typecode == TYPE_CODE_STRUCT
 549               || typecode == TYPE_CODE_UNION)
 550           && argreg > SCORE_LAST_ARG_REGNUM
 551           && arglen < SCORE_REGSIZE)
 552         downward_offset += (SCORE_REGSIZE - arglen);
 553
 554       while (arglen > 0)
 555         {
 556           int partial_len = arglen < SCORE_REGSIZE ? arglen : SCORE_REGSIZE;
 557           ULONGEST regval = extract_unsigned_integer (val, partial_len);
 558
 559           /* The last part of a arg should shift left when
 560              gdbarch_byte_order is BFD_ENDIAN_BIG.  */
 561           if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG
 562               && arg_last_part_p == 1
 563               && (typecode == TYPE_CODE_STRUCT
 564                   || typecode == TYPE_CODE_UNION))
 565             regval <<= ((SCORE_REGSIZE - partial_len) * TARGET_CHAR_BIT);
 566
 567           /* Always increase the stack_offset and save args to stack.  */
 568           addr = sp + stack_offset + downward_offset;
 569           write_memory (addr, val, partial_len);
 570
 571           if (argreg <= SCORE_LAST_ARG_REGNUM)
 572             {
 573               regcache_cooked_write_unsigned (regcache, argreg++, regval);
 574               if (arglen > SCORE_REGSIZE && arglen < SCORE_REGSIZE * 2)
 575                 arg_last_part_p = 1;
 576             }
 577
 578           val += partial_len;
 579           arglen -= partial_len;
 580           stack_offset += align_up (partial_len, SCORE_REGSIZE);
 581         }
 582     }
 583
 584   /* Step 5, Save SP.  */
 585   regcache_cooked_write_unsigned (regcache, SCORE_SP_REGNUM, sp);
 586
 587   return sp;
 588 }
 589
 590 static char *
 591 score_malloc_and_get_memblock (CORE_ADDR addr, CORE_ADDR size)
 592 {
 593   int ret;
 594   char *memblock = NULL;
 595
 596   if (size < 0)
 597     {
 598       error ("Error: malloc size < 0 in file:%s, line:%d!",
 599              __FILE__, __LINE__);
 600       return NULL;
 601     }
 602   else if (size == 0)
 603     return NULL;
 604
 605   memblock = (char *) xmalloc (size);
 606   memset (memblock, 0, size);
 607   ret = target_read_memory (addr & ~0x3, memblock, size);
 608   if (ret)
 609     {
 610       error ("Error: target_read_memory in file:%s, line:%d!",
 611              __FILE__, __LINE__);
 612       return NULL;
 613     }
 614   return memblock;
 615 }
 616
 617 static void
 618 score_free_memblock (char *memblock)
 619 {
 620   xfree (memblock);
 621 }
 622
 623 static void
 624 score_adjust_memblock_ptr (char **memblock, CORE_ADDR prev_pc,
 625                            CORE_ADDR cur_pc)
 626 {
 627   if (prev_pc == -1)
 628     {
 629       /* First time call this function, do nothing.  */
 630     }
 631   else if (cur_pc - prev_pc == 2 && (cur_pc & 0x3) == 0)
 632     {
 633       /* First 16-bit instruction, then 32-bit instruction.  */
 634       *memblock += SCORE_INSTLEN;
 635     }
 636   else if (cur_pc - prev_pc == 4)
 637     {
 638       /* Is 32-bit instruction, increase MEMBLOCK by 4.  */
 639       *memblock += SCORE_INSTLEN;
 640     }
 641 }
 642
 643 static inst_t *
 644 score_fetch_inst (CORE_ADDR addr, char *memblock)
 645 {
 646   static inst_t inst = { 0, 0 };
 647   char buf[SCORE_INSTLEN] = { 0 };
 648   int big;
 649   int ret;
 650
 651   if (target_has_execution && memblock != NULL)
 652     {
 653       /* Fetch instruction from local MEMBLOCK.  */
 654       memcpy (buf, memblock, SCORE_INSTLEN);
 655     }
 656   else
 657     {
 658       /* Fetch instruction from target.  */
 659       ret = target_read_memory (addr & ~0x3, buf, SCORE_INSTLEN);
 660       if (ret)
 661         {
 662           error ("Error: target_read_memory in file:%s, line:%d!",
 663                   __FILE__, __LINE__);
 664           return 0;
 665         }
 666     }
 667
 668   inst.raw = extract_unsigned_integer (buf, SCORE_INSTLEN);
 669   inst.is15 = !(inst.raw & 0x80008000);
 670   inst.v = RM_PBITS (inst.raw);
 671   big = (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG);
 672   if (inst.is15)
 673     {
 674       if (big ^ ((addr & 0x2) == 2))
 675         inst.v = G_FLD (inst.v, 29, 15);
 676       else
 677         inst.v = G_FLD (inst.v, 14, 0);
 678     }
 679   return &inst;
 680 }
 681
 682 static CORE_ADDR
 683 score_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
 684 {
 685   CORE_ADDR cpc = pc;
 686   int iscan = 32, stack_sub = 0;
 687   while (iscan-- > 0)
 688     {
 689       inst_t *inst = score_fetch_inst (cpc, NULL);
 690       if (!inst)
 691         break;
 692       if (!inst->is15 && !stack_sub
 693           && (G_FLD (inst->v, 29, 25) == 0x1
 694               && G_FLD (inst->v, 24, 20) == 0x0))
 695         {
 696           /* addi r0, offset */
 697           pc = stack_sub = cpc + SCORE_INSTLEN;
 698         }
 699       else if (!inst->is15
 700                && inst->v == RM_PBITS (0x8040bc56))
 701         {
 702           /* mv r2, r0  */
 703           pc = cpc + SCORE_INSTLEN;
 704           break;
 705         }
 706       else if (inst->is15
 707                && inst->v == RM_PBITS (0x0203))
 708         {
 709           /* mv! r2, r0 */
 710           pc = cpc + SCORE16_INSTLEN;
 711           break;
 712         }
 713       else if (inst->is15
 714                && ((G_FLD (inst->v, 14, 12) == 3)    /* j15 form */
 715                    || (G_FLD (inst->v, 14, 12) == 4) /* b15 form */
 716                    || (G_FLD (inst->v, 14, 12) == 0x0
 717                        && G_FLD (inst->v, 3, 0) == 0x4))) /* br! */
 718         break;
 719       else if (!inst->is15
 720                && ((G_FLD (inst->v, 29, 25) == 2)    /* j32 form */
 721                    || (G_FLD (inst->v, 29, 25) == 4) /* b32 form */
 722                    || (G_FLD (inst->v, 29, 25) == 0x0
 723                        && G_FLD (inst->v, 6, 1) == 0x4)))  /* br */
 724         break;
 725
 726       cpc += inst->is15 ? SCORE16_INSTLEN : SCORE_INSTLEN;
 727     }
 728   return pc;
 729 }
 730
 731 static int
 732 score_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR cur_pc)
 733 {
 734   inst_t *inst = score_fetch_inst (cur_pc, NULL);
 735
 736   if (inst->v == 0x23)
 737     return 1;   /* mv! r0, r2 */
 738   else if (G_FLD (inst->v, 14, 12) == 0x2
 739            && G_FLD (inst->v, 3, 0) == 0xa)
 740     return 1;   /* pop! */
 741   else if (G_FLD (inst->v, 14, 12) == 0x0
 742            && G_FLD (inst->v, 7, 0) == 0x34)
 743     return 1;   /* br! r3 */
 744   else if (G_FLD (inst->v, 29, 15) == 0x2
 745            && G_FLD (inst->v, 6, 1) == 0x2b)
 746     return 1;   /* mv r0, r2 */
 747   else if (G_FLD (inst->v, 29, 25) == 0x0
 748            && G_FLD (inst->v, 6, 1) == 0x4
 749            && G_FLD (inst->v, 19, 15) == 0x3)
 750     return 1;   /* br r3 */
 751   else
 752     return 0;
 753 }
 754
 755 static void
 756 score_analyze_prologue (CORE_ADDR startaddr, CORE_ADDR pc,
 757                         struct frame_info *next_frame,
 758                         struct score_frame_cache *this_cache)
 759 {
 760   CORE_ADDR sp;
 761   CORE_ADDR fp;
 762   CORE_ADDR cur_pc = startaddr;
 763
 764   int sp_offset = 0;
 765   int ra_offset = 0;
 766   int fp_offset = 0;
 767   int ra_offset_p = 0;
 768   int fp_offset_p = 0;
 769   int inst_len = 0;
 770
 771   char *memblock = NULL;
 772   char *memblock_ptr = NULL;
 773   CORE_ADDR prev_pc = -1;
 774
 775   /* Allocate MEMBLOCK if PC - STARTADDR > 0.  */
 776   memblock_ptr = memblock =
 777     score_malloc_and_get_memblock (startaddr, pc - startaddr);
 778
 779   sp = frame_unwind_register_unsigned (next_frame, SCORE_SP_REGNUM);
 780   fp = frame_unwind_register_unsigned (next_frame, SCORE_FP_REGNUM);
 781
 782   for (; cur_pc < pc; prev_pc = cur_pc, cur_pc += inst_len)
 783     {
 784       inst_t *inst = NULL;
 785       if (memblock != NULL)
 786         {
 787           /* Reading memory block from target succefully and got all
 788              the instructions(from STARTADDR to PC) needed.  */
 789           score_adjust_memblock_ptr (&memblock, prev_pc, cur_pc);
 790           inst = score_fetch_inst (cur_pc, memblock);
 791         }
 792       else
 793         {
 794           /* Otherwise, we fetch 4 bytes from target, and GDB also
 795              work correctly.  */
 796           inst = score_fetch_inst (cur_pc, NULL);
 797         }
 798
 799       if (inst->is15 == 1)
 800         {
 801           inst_len = SCORE16_INSTLEN;
 802
 803           if (G_FLD (inst->v, 14, 12) == 0x2
 804               && G_FLD (inst->v, 3, 0) == 0xe)
 805             {
 806               /* push! */
 807               sp_offset += 4;
 808
 809               if (G_FLD (inst->v, 11, 7) == 0x6
 810                   && ra_offset_p == 0)
 811                 {
 812                   /* push! r3, [r0] */
 813                   ra_offset = sp_offset;
 814                   ra_offset_p = 1;
 815                 }
 816               else if (G_FLD (inst->v, 11, 7) == 0x4
 817                        && fp_offset_p == 0)
 818                 {
 819                   /* push! r2, [r0] */
 820                   fp_offset = sp_offset;
 821                   fp_offset_p = 1;
 822                 }
 823             }
 824           else if (G_FLD (inst->v, 14, 12) == 0x2
 825                    && G_FLD (inst->v, 3, 0) == 0xa)
 826             {
 827               /* pop! */
 828               sp_offset -= 4;
 829             }
 830           else if (G_FLD (inst->v, 14, 7) == 0xc1
 831                    && G_FLD (inst->v, 2, 0) == 0x0)
 832             {
 833               /* subei! r0, n */
 834               sp_offset += (int) pow (2, G_FLD (inst->v, 6, 3));
 835             }
 836           else if (G_FLD (inst->v, 14, 7) == 0xc0
 837                    && G_FLD (inst->v, 2, 0) == 0x0)
 838             {
 839               /* addei! r0, n */
 840               sp_offset -= (int) pow (2, G_FLD (inst->v, 6, 3));
 841             }
 842         }
 843       else
 844         {
 845           inst_len = SCORE_INSTLEN;
 846
 847           if (G_FLD (inst->v, 29, 15) == 0xc60
 848               && G_FLD (inst->v, 2, 0) == 0x4)
 849             {
 850               /* sw r3, [r0, offset]+ */
 851               sp_offset += SCORE_INSTLEN;
 852               if (ra_offset_p == 0)
 853                 {
 854                   ra_offset = sp_offset;
 855                   ra_offset_p = 1;
 856                 }
 857             }
 858           if (G_FLD (inst->v, 29, 15) == 0xc40
 859               && G_FLD (inst->v, 2, 0) == 0x4)
 860             {
 861               /* sw r2, [r0, offset]+ */
 862               sp_offset += SCORE_INSTLEN;
 863               if (fp_offset_p == 0)
 864                 {
 865                   fp_offset = sp_offset;
 866                   fp_offset_p = 1;
 867                 }
 868             }
 869           else if (G_FLD (inst->v, 29, 15) == 0x1c60
 870                    && G_FLD (inst->v, 2, 0) == 0x0)
 871             {
 872               /* lw r3, [r0]+, 4 */
 873               sp_offset -= SCORE_INSTLEN;
 874               ra_offset_p = 1;
 875             }
 876           else if (G_FLD (inst->v, 29, 15) == 0x1c40
 877                    && G_FLD (inst->v, 2, 0) == 0x0)
 878             {
 879               /* lw r2, [r0]+, 4 */
 880               sp_offset -= SCORE_INSTLEN;
 881               fp_offset_p = 1;
 882             }
 883
 884           else if (G_FLD (inst->v, 29, 17) == 0x100
 885                    && G_FLD (inst->v, 0, 0) == 0x0)
 886             {
 887               /* addi r0, -offset */
 888               sp_offset += 65536 - G_FLD (inst->v, 16, 1);
 889             }
 890           else if (G_FLD (inst->v, 29, 17) == 0x110
 891                    && G_FLD (inst->v, 0, 0) == 0x0)
 892             {
 893               /* addi r2, offset */
 894               if (pc - cur_pc > 4)
 895                 {
 896                   unsigned int save_v = inst->v;
 897                   inst_t *inst2 =
 898                     score_fetch_inst (cur_pc + SCORE_INSTLEN, NULL);
 899                   if (inst2->v == 0x23)
 900                     {
 901                       /* mv! r0, r2 */
 902                       sp_offset -= G_FLD (save_v, 16, 1);
 903                     }
 904                 }
 905             }
 906         }
 907     }
 908
 909   /* Save RA.  */
 910   if (ra_offset_p == 1)
 911     {
 912       if (this_cache->saved_regs[SCORE_PC_REGNUM].addr == -1)
 913         this_cache->saved_regs[SCORE_PC_REGNUM].addr =
 914           sp + sp_offset - ra_offset;
 915     }
 916   else
 917     {
 918       this_cache->saved_regs[SCORE_PC_REGNUM] =
 919         this_cache->saved_regs[SCORE_RA_REGNUM];
 920     }
 921
 922   /* Save FP.  */
 923   if (fp_offset_p == 1)
 924     {
 925       if (this_cache->saved_regs[SCORE_FP_REGNUM].addr == -1)
 926         this_cache->saved_regs[SCORE_FP_REGNUM].addr =
 927           sp + sp_offset - fp_offset;
 928     }
 929
 930   /* Save SP and FP.  */
 931   this_cache->base = sp + sp_offset;
 932   this_cache->fp = fp;
 933
 934   /* Don't forget to free MEMBLOCK if we allocated it.  */
 935   if (memblock_ptr != NULL)
 936     score_free_memblock (memblock_ptr);
 937 }
 938
 939 static struct score_frame_cache *
 940 score_make_prologue_cache (struct frame_info *next_frame, void **this_cache)
 941 {
 942   struct score_frame_cache *cache;
 943
 944   if ((*this_cache) != NULL)
 945     return (*this_cache);
 946
 947   cache = FRAME_OBSTACK_ZALLOC (struct score_frame_cache);
 948   (*this_cache) = cache;
 949   cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
 950
 951   /* Analyze the prologue.  */
 952   {
 953     const CORE_ADDR pc = frame_pc_unwind (next_frame);
 954     CORE_ADDR start_addr;
 955
 956     find_pc_partial_function (pc, NULL, &start_addr, NULL);
 957     if (start_addr == 0)
 958       return cache;
 959     score_analyze_prologue (start_addr, pc, next_frame, *this_cache);
 960   }
 961
 962   /* Save SP.  */
 963   trad_frame_set_value (cache->saved_regs, SCORE_SP_REGNUM, cache->base);
 964
 965   return (*this_cache);
 966 }
 967
 968 static void
 969 score_prologue_this_id (struct frame_info *next_frame, void **this_cache,
 970                         struct frame_id *this_id)
 971 {
 972   struct score_frame_cache *info = score_make_prologue_cache (next_frame,
 973                                                               this_cache);
 974   (*this_id) = frame_id_build (info->base,
 975                                frame_func_unwind (next_frame, NORMAL_FRAME));
 976 }
 977
 978 static void
 979 score_prologue_prev_register (struct frame_info *next_frame,
 980                               void **this_cache,
 981                               int regnum, int *optimizedp,
 982                               enum lval_type *lvalp, CORE_ADDR * addrp,
 983                               int *realnump, gdb_byte * valuep)
 984 {
 985   struct score_frame_cache *info = score_make_prologue_cache (next_frame,
 986                                                               this_cache);
 987   trad_frame_get_prev_register (next_frame, info->saved_regs, regnum,
 988                                 optimizedp, lvalp, addrp, realnump, valuep);
 989 }
 990
 991 static const struct frame_unwind score_prologue_unwind =
 992 {
 993   NORMAL_FRAME,
 994   score_prologue_this_id,
 995   score_prologue_prev_register
 996 };
 997
 998 static const struct frame_unwind *
 999 score_prologue_sniffer (struct frame_info *next_frame)
1000 {
1001   return &score_prologue_unwind;
1002 }
1003
1004 static CORE_ADDR
1005 score_prologue_frame_base_address (struct frame_info *next_frame,
1006                                    void **this_cache)
1007 {
1008   struct score_frame_cache *info =
1009     score_make_prologue_cache (next_frame, this_cache);
1010   return info->fp;
1011 }
1012
1013 static const struct frame_base score_prologue_frame_base =
1014 {
1015   &score_prologue_unwind,
1016   score_prologue_frame_base_address,
1017   score_prologue_frame_base_address,
1018   score_prologue_frame_base_address,
1019 };
1020
1021 static const struct frame_base *
1022 score_prologue_frame_base_sniffer (struct frame_info *next_frame)
1023 {
1024   return &score_prologue_frame_base;
1025 }
1026
1027 static struct gdbarch *
1028 score_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
1029 {
1030   struct gdbarch *gdbarch;
1031
1032   arches = gdbarch_list_lookup_by_info (arches, &info);
1033   if (arches != NULL)
1034     {
1035       return (arches->gdbarch);
1036     }
1037   gdbarch = gdbarch_alloc (&info, 0);
1038
1039   set_gdbarch_short_bit (gdbarch, 16);
1040   set_gdbarch_int_bit (gdbarch, 32);
1041   set_gdbarch_float_bit (gdbarch, 32);
1042   set_gdbarch_double_bit (gdbarch, 64);
1043   set_gdbarch_long_double_bit (gdbarch, 64);
1044   set_gdbarch_register_sim_regno (gdbarch, score_register_sim_regno);
1045   set_gdbarch_pc_regnum (gdbarch, SCORE_PC_REGNUM);
1046   set_gdbarch_sp_regnum (gdbarch, SCORE_SP_REGNUM);
1047   set_gdbarch_num_regs (gdbarch, SCORE_NUM_REGS);
1048   set_gdbarch_register_name (gdbarch, score_register_name);
1049   set_gdbarch_breakpoint_from_pc (gdbarch, score_breakpoint_from_pc);
1050   set_gdbarch_register_type (gdbarch, score_register_type);
1051   set_gdbarch_frame_align (gdbarch, score_frame_align);
1052   set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
1053   set_gdbarch_unwind_pc (gdbarch, score_unwind_pc);
1054   set_gdbarch_unwind_sp (gdbarch, score_unwind_sp);
1055   set_gdbarch_print_insn (gdbarch, score_print_insn);
1056   set_gdbarch_skip_prologue (gdbarch, score_skip_prologue);
1057   set_gdbarch_in_function_epilogue_p (gdbarch, score_in_function_epilogue_p);
1058
1059   /* Watchpoint hooks.  */
1060   set_gdbarch_have_nonsteppable_watchpoint (gdbarch, 1);
1061
1062   /* Dummy frame hooks.  */
1063   set_gdbarch_return_value (gdbarch, score_return_value);
1064   set_gdbarch_call_dummy_location (gdbarch, AT_ENTRY_POINT);
1065   set_gdbarch_unwind_dummy_id (gdbarch, score_unwind_dummy_id);
1066   set_gdbarch_push_dummy_call (gdbarch, score_push_dummy_call);
1067
1068   /* Normal frame hooks.  */
1069   frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
1070   frame_base_append_sniffer (gdbarch, dwarf2_frame_base_sniffer);
1071   frame_unwind_append_sniffer (gdbarch, score_prologue_sniffer);
1072   frame_base_append_sniffer (gdbarch, score_prologue_frame_base_sniffer);
1073
1074   return gdbarch;
1075 }
1076
1077 extern initialize_file_ftype _initialize_score_tdep;
1078
1079 void
1080 _initialize_score_tdep (void)
1081 {
1082   gdbarch_register (bfd_arch_score, score_gdbarch_init, NULL);
1083 }