gas/config/tc-fr30.c

   1 /* tc-fr30.c -- Assembler for the Fujitsu FR30.
   2    Copyright (C) 1998 Free Software Foundation.
   3
   4    This file is part of GAS, the GNU Assembler.
   5
   6    GAS is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    GAS is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GAS; see the file COPYING.  If not, write to
  18    the Free Software Foundation, 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <stdio.h>
  22 #include <ctype.h>
  23 #include "as.h"
  24 #include "subsegs.h"
  25 #include "symcat.h"
  26 #include "cgen-opc.h"
  27 #include "cgen.h"
  28
  29 /* Linked list of symbols that are debugging symbols to be
  30    defined as the beginning of the current instruction.  */
  31 typedef struct sym_link
  32 {
  33   struct sym_link * next;
  34   symbolS *         symbol;
  35 } sym_linkS;
  36
  37 static sym_linkS *  debug_sym_link = (sym_linkS *) NULL;
  38
  39 /* Structure to hold all of the different components describing
  40    an individual instruction.  */
  41 typedef struct
  42 {
  43   const CGEN_INSN *     insn;
  44   const CGEN_INSN *     orig_insn;
  45   CGEN_FIELDS           fields;
  46 #if CGEN_INT_INSN_P
  47   CGEN_INSN_INT         buffer [1];
  48 #define INSN_VALUE(buf) (*(buf))
  49 #else
  50   unsigned char         buffer [CGEN_MAX_INSN_SIZE];
  51 #define INSN_VALUE(buf) (buf)
  52 #endif
  53   char *                addr;
  54   fragS *               frag;
  55   int                   num_fixups;
  56   fixS *                fixups [GAS_CGEN_MAX_FIXUPS];
  57   int                   indices [MAX_OPERAND_INSTANCES];
  58   sym_linkS *           debug_sym_link;
  59 }
  60 fr30_insn;
  61
  62 const char comment_chars[]        = ";";
  63 const char line_comment_chars[]   = "#";
  64 const char line_separator_chars[] = "";
  65 const char EXP_CHARS[]            = "eE";
  66 const char FLT_CHARS[]            = "dD";
  67 \f
  68 #define FR30_SHORTOPTS ""
  69 const char * md_shortopts = FR30_SHORTOPTS;
  70
  71 struct option md_longopts[] =
  72 {
  73   {NULL, no_argument, NULL, 0}
  74 };
  75 size_t md_longopts_size = sizeof (md_longopts);
  76
  77 int
  78 md_parse_option (c, arg)
  79      int    c;
  80      char * arg;
  81 {
  82   switch (c)
  83     {
  84     default:
  85       return 0;
  86     }
  87   return 1;
  88 }
  89
  90 void
  91 md_show_usage (stream)
  92   FILE * stream;
  93 {
  94   fprintf (stream, _(" FR30 specific command line options:\n"));
  95 }
  96
  97 /* The target specific pseudo-ops which we support.  */
  98 const pseudo_typeS md_pseudo_table[] =
  99 {
 100   { "word",     cons,           4 },
 101   { NULL,       NULL,           0 }
 102 };
 103
 104 \f
 105 void
 106 md_begin ()
 107 {
 108   flagword applicable;
 109   segT     seg;
 110   subsegT  subseg;
 111
 112   /* Initialize the `cgen' interface.  */
 113
 114   /* Set the machine number and endian.  */
 115   gas_cgen_opcode_desc = fr30_cgen_opcode_open (bfd_mach_fr30, CGEN_ENDIAN_BIG);
 116   fr30_cgen_init_asm (gas_cgen_opcode_desc);
 117
 118   /* This is a callback from cgen to gas to parse operands.  */
 119   cgen_set_parse_operand_fn (gas_cgen_opcode_desc, gas_cgen_parse_operand);
 120 }
 121
 122 void
 123 md_assemble (str)
 124      char * str;
 125 {
 126   fr30_insn insn;
 127   char *    errmsg;
 128   char *    str2 = NULL;
 129
 130   /* Initialize GAS's cgen interface for a new instruction.  */
 131   gas_cgen_init_parse ();
 132
 133   insn.debug_sym_link = debug_sym_link;
 134   debug_sym_link = (sym_linkS *)0;
 135
 136   insn.insn = fr30_cgen_assemble_insn
 137     (gas_cgen_opcode_desc, str, & insn.fields, insn.buffer, & errmsg);
 138
 139   if (!insn.insn)
 140     {
 141       as_bad (errmsg);
 142       return;
 143     }
 144
 145   /* Doesn't really matter what we pass for RELAX_P here.  */
 146   gas_cgen_finish_insn (insn.insn, insn.buffer,
 147                         CGEN_FIELDS_BITSIZE (& insn.fields), 1, NULL);
 148 }
 149
 150 /* The syntax in the manual says constants begin with '#'.
 151    We just ignore it.  */
 152
 153 void
 154 md_operand (expressionP)
 155      expressionS * expressionP;
 156 {
 157   if (* input_line_pointer == '#')
 158     {
 159       input_line_pointer ++;
 160       expression (expressionP);
 161     }
 162 }
 163
 164 valueT
 165 md_section_align (segment, size)
 166      segT   segment;
 167      valueT size;
 168 {
 169   int align = bfd_get_section_alignment (stdoutput, segment);
 170   return ((size + (1 << align) - 1) & (-1 << align));
 171 }
 172
 173 symbolS *
 174 md_undefined_symbol (name)
 175   char * name;
 176 {
 177   return 0;
 178 }
 179 \f
 180 /* Interface to relax_segment.  */
 181
 182 /* FIXME: Build table by hand, get it working, then machine generate.  */
 183
 184 const relax_typeS md_relax_table[] =
 185 {
 186 /* The fields are:
 187    1) most positive reach of this state,
 188    2) most negative reach of this state,
 189    3) how many bytes this mode will add to the size of the current frag
 190    4) which index into the table to try if we can't fit into this one.  */
 191
 192   /* The first entry must be unused because an `rlx_more' value of zero ends
 193      each list.  */
 194   {1, 1, 0, 0},
 195
 196   /* The displacement used by GAS is from the end of the 2 byte insn,
 197      so we subtract 2 from the following.  */
 198   /* 16 bit insn, 8 bit disp -> 10 bit range.
 199      This doesn't handle a branch in the right slot at the border:
 200      the "& -4" isn't taken into account.  It's not important enough to
 201      complicate things over it, so we subtract an extra 2 (or + 2 in -ve
 202      case).  */
 203   {511 - 2 - 2, -512 - 2 + 2, 0, 2 },
 204   /* 32 bit insn, 24 bit disp -> 26 bit range.  */
 205   {0x2000000 - 1 - 2, -0x2000000 - 2, 2, 0 },
 206   /* Same thing, but with leading nop for alignment.  */
 207   {0x2000000 - 1 - 2, -0x2000000 - 2, 4, 0 }
 208 };
 209
 210 long
 211 fr30_relax_frag (fragP, stretch)
 212      fragS * fragP;
 213      long    stretch;
 214 {
 215   /* Address of branch insn.  */
 216   long address = fragP->fr_address + fragP->fr_fix - 2;
 217   long growth = 0;
 218
 219   /* Keep 32 bit insns aligned on 32 bit boundaries.  */
 220   if (fragP->fr_subtype == 2)
 221     {
 222       if ((address & 3) != 0)
 223         {
 224           fragP->fr_subtype = 3;
 225           growth = 2;
 226         }
 227     }
 228   else if (fragP->fr_subtype == 3)
 229     {
 230       if ((address & 3) == 0)
 231         {
 232           fragP->fr_subtype = 2;
 233           growth = -2;
 234         }
 235     }
 236   else
 237     {
 238       growth = relax_frag (fragP, stretch);
 239
 240       /* Long jump on odd halfword boundary?  */
 241       if (fragP->fr_subtype == 2 && (address & 3) != 0)
 242         {
 243           fragP->fr_subtype = 3;
 244           growth += 2;
 245         }
 246     }
 247
 248   return growth;
 249 }
 250
 251 /* Return an initial guess of the length by which a fragment must grow to
 252    hold a branch to reach its destination.
 253    Also updates fr_type/fr_subtype as necessary.
 254
 255    Called just before doing relaxation.
 256    Any symbol that is now undefined will not become defined.
 257    The guess for fr_var is ACTUALLY the growth beyond fr_fix.
 258    Whatever we do to grow fr_fix or fr_var contributes to our returned value.
 259    Although it may not be explicit in the frag, pretend fr_var starts with a
 260    0 value.  */
 261
 262 int
 263 md_estimate_size_before_relax (fragP, segment)
 264      fragS * fragP;
 265      segT    segment;
 266 {
 267   int    old_fr_fix = fragP->fr_fix;
 268
 269   /* The only thing we have to handle here are symbols outside of the
 270      current segment.  They may be undefined or in a different segment in
 271      which case linker scripts may place them anywhere.
 272      However, we can't finish the fragment here and emit the reloc as insn
 273      alignment requirements may move the insn about.  */
 274
 275   if (S_GET_SEGMENT (fragP->fr_symbol) != segment)
 276     {
 277       /* The symbol is undefined in this segment.
 278          Change the relaxation subtype to the max allowable and leave
 279          all further handling to md_convert_frag.  */
 280       fragP->fr_subtype = 2;
 281
 282 #if 0 /* Can't use this, but leave in for illustration.  */
 283       /* Change 16 bit insn to 32 bit insn.  */
 284       fragP->fr_opcode[0] |= 0x80;
 285
 286       /* Increase known (fixed) size of fragment.  */
 287       fragP->fr_fix += 2;
 288
 289       /* Create a relocation for it.  */
 290       fix_new (fragP, old_fr_fix, 4,
 291                fragP->fr_symbol,
 292                fragP->fr_offset, 1 /* pcrel */,
 293                /* FIXME: Can't use a real BFD reloc here.
 294                   gas_cgen_md_apply_fix3 can't handle it.  */
 295                BFD_RELOC_FR30_26_PCREL);
 296
 297       /* Mark this fragment as finished.  */
 298       frag_wane (fragP);
 299 #else
 300       {
 301         const CGEN_INSN * insn;
 302         int               i;
 303
 304         /* Update the recorded insn.
 305            Fortunately we don't have to look very far.
 306            FIXME: Change this to record in the instruction the next higher
 307            relaxable insn to use.  */
 308         for (i = 0, insn = fragP->fr_cgen.insn; i < 4; i++, insn++)
 309           {
 310             if ((strcmp (CGEN_INSN_MNEMONIC (insn),
 311                          CGEN_INSN_MNEMONIC (fragP->fr_cgen.insn))
 312                  == 0)
 313                 && CGEN_INSN_ATTR (insn, CGEN_INSN_RELAX))
 314               break;
 315           }
 316         if (i == 4)
 317           abort ();
 318
 319         fragP->fr_cgen.insn = insn;
 320         return 2;
 321       }
 322 #endif
 323     }
 324
 325   return (fragP->fr_var + fragP->fr_fix - old_fr_fix);
 326 }
 327
 328 /* *fragP has been relaxed to its final size, and now needs to have
 329    the bytes inside it modified to conform to the new size.
 330
 331    Called after relaxation is finished.
 332    fragP->fr_type == rs_machine_dependent.
 333    fragP->fr_subtype is the subtype of what the address relaxed to.  */
 334
 335 void
 336 md_convert_frag (abfd, sec, fragP)
 337   bfd *   abfd;
 338   segT    sec;
 339   fragS * fragP;
 340 {
 341 #if 0
 342   char * opcode;
 343   char * displacement;
 344   int    target_address;
 345   int    opcode_address;
 346   int    extension;
 347   int    addend;
 348
 349   opcode = fragP->fr_opcode;
 350
 351   /* Address opcode resides at in file space.  */
 352   opcode_address = fragP->fr_address + fragP->fr_fix - 2;
 353
 354   switch (fragP->fr_subtype)
 355     {
 356     case 1 :
 357       extension = 0;
 358       displacement = & opcode[1];
 359       break;
 360     case 2 :
 361       opcode[0] |= 0x80;
 362       extension = 2;
 363       displacement = & opcode[1];
 364       break;
 365     case 3 :
 366       opcode[2] = opcode[0] | 0x80;
 367       md_number_to_chars (opcode, PAR_NOP_INSN, 2);
 368       opcode_address += 2;
 369       extension = 4;
 370       displacement = & opcode[3];
 371       break;
 372     default :
 373       abort ();
 374     }
 375
 376   if (S_GET_SEGMENT (fragP->fr_symbol) != sec)
 377     {
 378       /* symbol must be resolved by linker */
 379       if (fragP->fr_offset & 3)
 380         as_warn (_("Addend to unresolved symbol not on word boundary."));
 381       addend = fragP->fr_offset >> 2;
 382     }
 383   else
 384     {
 385       /* Address we want to reach in file space.  */
 386       target_address = S_GET_VALUE (fragP->fr_symbol) + fragP->fr_offset;
 387       target_address += fragP->fr_symbol->sy_frag->fr_address;
 388       addend = (target_address - (opcode_address & -4)) >> 2;
 389     }
 390
 391   /* Create a relocation for symbols that must be resolved by the linker.
 392      Otherwise output the completed insn.  */
 393
 394   if (S_GET_SEGMENT (fragP->fr_symbol) != sec)
 395     {
 396       assert (fragP->fr_subtype != 1);
 397       assert (fragP->fr_cgen.insn != 0);
 398       gas_cgen_record_fixup (fragP,
 399                              /* Offset of branch insn in frag.  */
 400                              fragP->fr_fix + extension - 4,
 401                              fragP->fr_cgen.insn,
 402                              4 /*length*/,
 403                              /* FIXME: quick hack */
 404 #if 0
 405                              CGEN_OPERAND_ENTRY (fragP->fr_cgen.opindex),
 406 #else
 407                              CGEN_OPERAND_ENTRY (FR30_OPERAND_DISP24),
 408 #endif
 409                              fragP->fr_cgen.opinfo,
 410                              fragP->fr_symbol, fragP->fr_offset);
 411     }
 412
 413 #define SIZE_FROM_RELAX_STATE(n) ((n) == 1 ? 1 : 3)
 414
 415   md_number_to_chars (displacement, (valueT) addend,
 416                       SIZE_FROM_RELAX_STATE (fragP->fr_subtype));
 417
 418   fragP->fr_fix += extension;
 419 #endif
 420 }
 421 \f
 422 /* Functions concerning relocs.  */
 423
 424 /* The location from which a PC relative jump should be calculated,
 425    given a PC relative reloc.  */
 426
 427 long
 428 md_pcrel_from_section (fixP, sec)
 429      fixS * fixP;
 430      segT   sec;
 431 {
 432   if (fixP->fx_addsy != (symbolS *) NULL
 433       && (! S_IS_DEFINED (fixP->fx_addsy)
 434           || S_GET_SEGMENT (fixP->fx_addsy) != sec))
 435     {
 436       /* The symbol is undefined (or is defined but not in this section).
 437          Let the linker figure it out.  */
 438       return 0;
 439     }
 440
 441   return (fixP->fx_frag->fr_address + fixP->fx_where) & -4L;
 442 }
 443
 444 /* Return the bfd reloc type for OPERAND of INSN at fixup FIXP.
 445    Returns BFD_RELOC_NONE if no reloc type can be found.
 446    *FIXP may be modified if desired.  */
 447
 448 bfd_reloc_code_real_type
 449 md_cgen_lookup_reloc (insn, operand, fixP)
 450      const CGEN_INSN *    insn;
 451      const CGEN_OPERAND * operand;
 452      fixS *               fixP;
 453 {
 454   switch (CGEN_OPERAND_TYPE (operand))
 455     {
 456     case FR30_OPERAND_PC :   return BFD_RELOC_FR30_12_PCREL;
 457     case FR30_OPERAND_RI :
 458     case FR30_OPERAND_RJ :
 459     case FR30_OPERAND_NBIT :
 460     case FR30_OPERAND_VBIT :
 461     case FR30_OPERAND_ZBIT :
 462     case FR30_OPERAND_CBIT :
 463     default : /* avoid -Wall warning */
 464       break;
 465     }
 466
 467   return BFD_RELOC_NONE;
 468 }
 469
 470
 471 /* Return BFD reloc type from opinfo field in a fixS.
 472    It's tricky using fx_r_type in fr30_frob_file because the values
 473    are BFD_RELOC_UNUSED + operand number.  */
 474 #define FX_OPINFO_R_TYPE(f) ((f)->tc_fix_data.opinfo)
 475
 476 /* See whether we need to force a relocation into the output file.
 477    This is used to force out switch and PC relative relocations when
 478    relaxing.  */
 479
 480 int
 481 fr30_force_relocation (fix)
 482      fixS * fix;
 483 {
 484   if (fix->fx_r_type == BFD_RELOC_VTABLE_INHERIT
 485       || fix->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
 486     return 1;
 487
 488   return fix->fx_pcrel;
 489 }
 490 \f
 491 /* Write a value out to the object file, using the appropriate endianness.  */
 492
 493 void
 494 md_number_to_chars (buf, val, n)
 495      char * buf;
 496      valueT val;
 497      int    n;
 498 {
 499   number_to_chars_bigendian (buf, val, n);
 500 }
 501
 502 /* Turn a string in input_line_pointer into a floating point constant of type
 503    type, and store the appropriate bytes in *litP.  The number of LITTLENUMS
 504    emitted is stored in *sizeP .  An error message is returned, or NULL on OK.
 505 */
 506
 507 /* Equal to MAX_PRECISION in atof-ieee.c */
 508 #define MAX_LITTLENUMS 6
 509
 510 char *
 511 md_atof (type, litP, sizeP)
 512      char   type;
 513      char * litP;
 514      int *  sizeP;
 515 {
 516   int              i;
 517   int              prec;
 518   LITTLENUM_TYPE   words [MAX_LITTLENUMS];
 519   char *           t;
 520   char *           atof_ieee ();
 521
 522   switch (type)
 523     {
 524     case 'f':
 525     case 'F':
 526     case 's':
 527     case 'S':
 528       prec = 2;
 529       break;
 530
 531     case 'd':
 532     case 'D':
 533     case 'r':
 534     case 'R':
 535       prec = 4;
 536       break;
 537
 538    /* FIXME: Some targets allow other format chars for bigger sizes here.  */
 539
 540     default:
 541       * sizeP = 0;
 542       return _("Bad call to md_atof()");
 543     }
 544
 545   t = atof_ieee (input_line_pointer, type, words);
 546   if (t)
 547     input_line_pointer = t;
 548   * sizeP = prec * sizeof (LITTLENUM_TYPE);
 549
 550   for (i = 0; i < prec; i++)
 551     {
 552       md_number_to_chars (litP, (valueT) words[i],
 553                           sizeof (LITTLENUM_TYPE));
 554       litP += sizeof (LITTLENUM_TYPE);
 555     }
 556
 557   return 0;
 558 }
 559
 560 static char
 561 restore_colon (advance_i_l_p_by)
 562      int advance_i_l_p_by;
 563 {
 564   char c;
 565
 566   /* Restore the colon, and advance input_line_pointer to
 567      the end of the new symbol.  */
 568   * input_line_pointer = ':';
 569   input_line_pointer += advance_i_l_p_by;
 570   c = * input_line_pointer;
 571   * input_line_pointer = 0;
 572
 573   return c;
 574 }
 575
 576 /* Determines if the symbol starting at START and ending in
 577    a colon that was at the location pointed to by INPUT_LINE_POINTER
 578    (but which has now been replaced bu a NUL) is in fact an
 579    LDI:8, LDI:20, LDI:32, CALL:D. JMP:D, RET:D or Bcc:D instruction.
 580    If it is, then it restores the colon, adbvances INPUT_LINE_POINTER
 581    to the real end of the instruction/symbol, and returns the character
 582    that really terminated the symbol.  Otherwise it returns 0.  */
 583 char
 584 fr30_is_colon_insn (start)
 585      char *  start;
 586 {
 587   char * i_l_p = input_line_pointer;
 588
 589   /* Check to see if the symbol parsed so far is 'ldi'  */
 590   if (   (start[0] != 'l' && start[0] != 'L')
 591       || (start[1] != 'd' && start[1] != 'D')
 592       || (start[2] != 'i' && start[2] != 'I')
 593       || start[3] != 0)
 594     {
 595       /* Nope - check to see a 'd' follows the colon.  */
 596       if (   (i_l_p[1] == 'd' || i_l_p[1] == 'D')
 597           && (i_l_p[2] == ' ' || i_l_p[2] == '\t' || i_l_p[2] == '\n'))
 598         {
 599           /* Yup - it might be delay slot instruction.  */
 600           int           i;
 601           static char * delay_insns [] =
 602           {
 603             "call", "jmp", "ret", "bra", "bno",
 604             "beq", "bne", "bc", "bnc", "bn", "bp",
 605             "bv", "bnv", "blt", "bge", "ble", "bgt",
 606             "bls", "bhi"
 607           };
 608
 609           for (i = sizeof (delay_insns) / sizeof (delay_insns[0]); i--;)
 610             {
 611               char * insn = delay_insns[i];
 612               int    len  = strlen (insn);
 613
 614               if (start [len] != 0)
 615                 continue;
 616
 617               while (len --)
 618                 {
 619                   if (tolower (start [len]) != insn [len])
 620                     break;
 621                 }
 622
 623               if (len == -1)
 624                 return restore_colon (1);
 625             }
 626         }
 627
 628       /* Nope - it is a normal label.  */
 629       return 0;
 630     }
 631
 632   /* Check to see if the text following the colon is '8' */
 633   if (i_l_p[1] == '8' && (i_l_p[2] == ' ' || i_l_p[2] == '\t'))
 634     {
 635       return restore_colon (2);
 636     }
 637
 638   /* Check to see if the text following the colon is '20' */
 639   else if (i_l_p[1] == '2' && i_l_p[2] =='0' && (i_l_p[3] == ' ' || i_l_p[3] == '\t'))
 640     {
 641       return restore_colon (3);
 642     }
 643
 644   /* Check to see if the text following the colon is '32' */
 645   else if (i_l_p[1] == '3' && i_l_p[2] =='2' && (i_l_p[3] == ' ' || i_l_p[3] == '\t'))
 646     {
 647       return restore_colon (3);
 648     }
 649
 650   return 0;
 651 }