gas/config/tc-xstormy16.c

   1 /* tc-xstormy16.c -- Assembler for the Sanyo XSTORMY16.
   2    Copyright 2000, 2001, 2002, 2003 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 "as.h"
  23 #include "subsegs.h"
  24 #include "symcat.h"
  25 #include "opcodes/xstormy16-desc.h"
  26 #include "opcodes/xstormy16-opc.h"
  27 #include "cgen.h"
  28
  29 /* Structure to hold all of the different components describing
  30    an individual instruction.  */
  31 typedef struct
  32 {
  33   const CGEN_INSN *     insn;
  34   const CGEN_INSN *     orig_insn;
  35   CGEN_FIELDS           fields;
  36 #if CGEN_INT_INSN_P
  37   CGEN_INSN_INT         buffer [1];
  38 #define INSN_VALUE(buf) (*(buf))
  39 #else
  40   unsigned char         buffer [CGEN_MAX_INSN_SIZE];
  41 #define INSN_VALUE(buf) (buf)
  42 #endif
  43   char *                addr;
  44   fragS *               frag;
  45   int                   num_fixups;
  46   fixS *                fixups [GAS_CGEN_MAX_FIXUPS];
  47   int                   indices [MAX_OPERAND_INSTANCES];
  48 }
  49 xstormy16_insn;
  50
  51 const char comment_chars[]        = ";";
  52 const char line_comment_chars[]   = "#";
  53 const char line_separator_chars[] = "|";
  54 const char EXP_CHARS[]            = "eE";
  55 const char FLT_CHARS[]            = "dD";
  56
  57 #define O_fptr_symbol   (O_max + 1)
  58 \f
  59 #define XSTORMY16_SHORTOPTS ""
  60 const char * md_shortopts = XSTORMY16_SHORTOPTS;
  61
  62 struct option md_longopts[] =
  63 {
  64   {NULL, no_argument, NULL, 0}
  65 };
  66 size_t md_longopts_size = sizeof (md_longopts);
  67
  68 int
  69 md_parse_option (c, arg)
  70      int    c ATTRIBUTE_UNUSED;
  71      char * arg ATTRIBUTE_UNUSED;
  72 {
  73   return 0;
  74 }
  75
  76 void
  77 md_show_usage (stream)
  78   FILE * stream;
  79 {
  80   fprintf (stream, _(" XSTORMY16 specific command line options:\n"));
  81 }
  82
  83 /* The target specific pseudo-ops which we support.  */
  84 const pseudo_typeS md_pseudo_table[] =
  85 {
  86   { "word",     cons,           4 },
  87   { NULL,       NULL,           0 }
  88 };
  89
  90 \f
  91 void
  92 md_begin ()
  93 {
  94   /* Initialize the `cgen' interface.  */
  95
  96   /* Set the machine number and endian.  */
  97   gas_cgen_cpu_desc = xstormy16_cgen_cpu_open (CGEN_CPU_OPEN_MACHS, 0,
  98                                           CGEN_CPU_OPEN_ENDIAN,
  99                                           CGEN_ENDIAN_LITTLE,
 100                                           CGEN_CPU_OPEN_END);
 101   xstormy16_cgen_init_asm (gas_cgen_cpu_desc);
 102
 103   /* This is a callback from cgen to gas to parse operands.  */
 104   cgen_set_parse_operand_fn (gas_cgen_cpu_desc, gas_cgen_parse_operand);
 105 }
 106
 107 static bfd_boolean skipping_fptr = FALSE;
 108
 109 void
 110 md_assemble (str)
 111      char * str;
 112 {
 113   xstormy16_insn insn;
 114   char *    errmsg;
 115
 116   /* Make sure that if we had an erroneous input line which triggered
 117      the skipping_fptr boolean that it does not affect following lines.  */
 118   skipping_fptr = FALSE;
 119
 120   /* Initialize GAS's cgen interface for a new instruction.  */
 121   gas_cgen_init_parse ();
 122
 123   insn.insn = xstormy16_cgen_assemble_insn
 124     (gas_cgen_cpu_desc, str, & insn.fields, insn.buffer, & errmsg);
 125
 126   if (!insn.insn)
 127     {
 128       as_bad (errmsg);
 129       return;
 130     }
 131
 132   /* Doesn't really matter what we pass for RELAX_P here.  */
 133   gas_cgen_finish_insn (insn.insn, insn.buffer,
 134                         CGEN_FIELDS_BITSIZE (& insn.fields), 0, NULL);
 135 }
 136
 137 void
 138 md_operand (e)
 139      expressionS * e;
 140 {
 141   if (*input_line_pointer != '@')
 142     return;
 143
 144   if (strncmp (input_line_pointer + 1, "fptr", 4) == 0)
 145     {
 146       input_line_pointer += 5;
 147       SKIP_WHITESPACE ();
 148       if (*input_line_pointer != '(')
 149         {
 150           as_bad ("Expected '('");
 151           goto err;
 152         }
 153       input_line_pointer++;
 154
 155       expression (e);
 156
 157       if (*input_line_pointer != ')')
 158         {
 159           as_bad ("Missing ')'");
 160           goto err;
 161         }
 162       input_line_pointer++;
 163       SKIP_WHITESPACE ();
 164
 165       if (e->X_op != O_symbol)
 166         as_bad ("Not a symbolic expression");
 167       else if (* input_line_pointer == '-')
 168         /* We are computing the difference of two function pointers
 169            like this:
 170
 171             .hword  @fptr (foo) - @fptr (bar)
 172
 173           In this situation we do not want to generate O_fptr_symbol
 174           operands because the result is an absolute value, not a
 175           function pointer.
 176
 177           We need to make the check here, rather than when the fixup
 178           is generated as the function names (foo & bar in the above
 179           example) might be local symbols and we want the expression
 180           to be evaluated now.  This kind of thing can happen when
 181           gcc is generating computed gotos.  */
 182         skipping_fptr = TRUE;
 183       else if (skipping_fptr)
 184         skipping_fptr = FALSE;
 185       else
 186         e->X_op = O_fptr_symbol;
 187     }
 188
 189   return;
 190  err:
 191   ignore_rest_of_line ();
 192 }
 193
 194 /* Called while parsing data to create a fixup.
 195    Create BFD_RELOC_XSTORMY16_FPTR16 relocations.  */
 196
 197 void
 198 xstormy16_cons_fix_new (f, where, nbytes, exp)
 199      fragS *f;
 200      int where;
 201      int nbytes;
 202      expressionS *exp;
 203 {
 204   bfd_reloc_code_real_type code;
 205   fixS *fix;
 206
 207   if (exp->X_op == O_fptr_symbol)
 208     {
 209       if (nbytes != 2)
 210         {
 211           as_bad ("unsupported fptr fixup size %d", nbytes);
 212           return;
 213         }
 214       exp->X_op = O_symbol;
 215       code = BFD_RELOC_XSTORMY16_FPTR16;
 216     }
 217   else if (nbytes == 1)
 218     code = BFD_RELOC_8;
 219   else if (nbytes == 2)
 220     code = BFD_RELOC_16;
 221   else if (nbytes == 4)
 222     code = BFD_RELOC_32;
 223   else
 224     {
 225       as_bad ("unsupported fixup size %d", nbytes);
 226       return;
 227     }
 228
 229   fix = fix_new_exp (f, where, nbytes, exp, 0, code);
 230 }
 231
 232 /* Called while parsing an instruction to create a fixup.
 233    Create BFD_RELOC_XSTORMY16_FPTR16 relocations.  */
 234
 235 fixS *
 236 xstormy16_cgen_record_fixup_exp (frag, where, insn, length, operand, opinfo, exp)
 237      fragS *              frag;
 238      int                  where;
 239      const CGEN_INSN *    insn;
 240      int                  length;
 241      const CGEN_OPERAND * operand;
 242      int                  opinfo;
 243      expressionS *        exp;
 244 {
 245   fixS *fixP;
 246   operatorT op = exp->X_op;
 247
 248   if (op == O_fptr_symbol)
 249     exp->X_op = O_symbol;
 250
 251   fixP = gas_cgen_record_fixup_exp (frag, where, insn, length,
 252                                     operand, opinfo, exp);
 253
 254   if (op == O_fptr_symbol)
 255     {
 256       if (operand->type != XSTORMY16_OPERAND_IMM16)
 257         as_bad ("unsupported fptr fixup");
 258       else
 259         {
 260           fixP->fx_r_type = BFD_RELOC_XSTORMY16_FPTR16;
 261           fixP->fx_where += 2;
 262         }
 263     }
 264
 265   return fixP;
 266 }
 267
 268 valueT
 269 md_section_align (segment, size)
 270      segT   segment;
 271      valueT size;
 272 {
 273   int align = bfd_get_section_alignment (stdoutput, segment);
 274   return ((size + (1 << align) - 1) & (-1 << align));
 275 }
 276
 277 symbolS *
 278 md_undefined_symbol (name)
 279   char * name ATTRIBUTE_UNUSED;
 280 {
 281   return 0;
 282 }
 283 \f
 284 /* Return an initial guess of the length by which a fragment must grow to
 285    hold a branch to reach its destination.
 286    Also updates fr_type/fr_subtype as necessary.
 287
 288    Called just before doing relaxation.
 289    Any symbol that is now undefined will not become defined.
 290    The guess for fr_var is ACTUALLY the growth beyond fr_fix.
 291    Whatever we do to grow fr_fix or fr_var contributes to our returned value.
 292    Although it may not be explicit in the frag, pretend fr_var starts with a
 293    0 value.  */
 294
 295 int
 296 md_estimate_size_before_relax (fragP, segment)
 297      fragS * fragP ATTRIBUTE_UNUSED;
 298      segT    segment ATTRIBUTE_UNUSED;
 299 {
 300   /* No assembler relaxation is defined (or necessary) for this port.  */
 301   abort ();
 302 }
 303
 304 /* *fragP has been relaxed to its final size, and now needs to have
 305    the bytes inside it modified to conform to the new size.
 306
 307    Called after relaxation is finished.
 308    fragP->fr_type == rs_machine_dependent.
 309    fragP->fr_subtype is the subtype of what the address relaxed to.  */
 310
 311 void
 312 md_convert_frag (abfd, sec, fragP)
 313   bfd *   abfd ATTRIBUTE_UNUSED;
 314   segT    sec ATTRIBUTE_UNUSED;
 315   fragS * fragP ATTRIBUTE_UNUSED;
 316 {
 317   /* No assembler relaxation is defined (or necessary) for this port.  */
 318   abort ();
 319 }
 320 \f
 321 /* Functions concerning relocs.  */
 322
 323 /* The location from which a PC relative jump should be calculated,
 324    given a PC relative reloc.  */
 325
 326 long
 327 md_pcrel_from_section (fixP, sec)
 328      fixS * fixP;
 329      segT   sec;
 330 {
 331   if (fixP->fx_addsy != (symbolS *) NULL
 332       && (! S_IS_DEFINED (fixP->fx_addsy)
 333           || S_GET_SEGMENT (fixP->fx_addsy) != sec)
 334           || xstormy16_force_relocation (fixP))
 335     /* The symbol is undefined,
 336        or it is defined but not in this section,
 337        or the relocation will be relative to this symbol not the section symbol.
 338        Let the linker figure it out.  */
 339     return 0;
 340
 341   return fixP->fx_frag->fr_address + fixP->fx_where;
 342 }
 343
 344 /* Return the bfd reloc type for OPERAND of INSN at fixup FIXP.
 345    Returns BFD_RELOC_NONE if no reloc type can be found.
 346    *FIXP may be modified if desired.  */
 347
 348 bfd_reloc_code_real_type
 349 md_cgen_lookup_reloc (insn, operand, fixP)
 350      const CGEN_INSN *    insn ATTRIBUTE_UNUSED;
 351      const CGEN_OPERAND * operand;
 352      fixS *               fixP;
 353 {
 354   switch (operand->type)
 355     {
 356     case XSTORMY16_OPERAND_IMM2:
 357     case XSTORMY16_OPERAND_IMM3:
 358     case XSTORMY16_OPERAND_IMM3B:
 359     case XSTORMY16_OPERAND_IMM4:
 360     case XSTORMY16_OPERAND_HMEM8:
 361       return BFD_RELOC_NONE;
 362
 363     case XSTORMY16_OPERAND_IMM12:
 364       fixP->fx_where += 2;
 365       return BFD_RELOC_XSTORMY16_12;
 366
 367     case XSTORMY16_OPERAND_IMM8:
 368     case XSTORMY16_OPERAND_LMEM8:
 369       return fixP->fx_pcrel ? BFD_RELOC_8_PCREL : BFD_RELOC_8;
 370
 371     case XSTORMY16_OPERAND_IMM16:
 372       /* This might have been processed at parse time.  */
 373       fixP->fx_where += 2;
 374       if (fixP->fx_cgen.opinfo && fixP->fx_cgen.opinfo != BFD_RELOC_NONE)
 375         return fixP->fx_cgen.opinfo;
 376       return fixP->fx_pcrel ? BFD_RELOC_16_PCREL : BFD_RELOC_16;
 377
 378     case XSTORMY16_OPERAND_ABS24:
 379       return BFD_RELOC_XSTORMY16_24;
 380
 381     case XSTORMY16_OPERAND_REL8_4:
 382       fixP->fx_addnumber -= 2;
 383     case XSTORMY16_OPERAND_REL8_2:
 384       fixP->fx_addnumber -= 2;
 385       fixP->fx_pcrel = 1;
 386       return BFD_RELOC_8_PCREL;
 387
 388     case XSTORMY16_OPERAND_REL12:
 389       fixP->fx_where += 2;
 390       /* Fall through...  */
 391     case XSTORMY16_OPERAND_REL12A:
 392       fixP->fx_addnumber -= 2;
 393       fixP->fx_pcrel = 1;
 394       return BFD_RELOC_XSTORMY16_REL_12;
 395
 396     default : /* avoid -Wall warning */
 397       abort ();
 398     }
 399 }
 400
 401 /* See whether we need to force a relocation into the output file.
 402    This is used to force out switch and PC relative relocations when
 403    relaxing.  */
 404
 405 int
 406 xstormy16_force_relocation (fix)
 407      fixS * fix;
 408 {
 409   if (fix->fx_r_type == BFD_RELOC_XSTORMY16_FPTR16)
 410     return 1;
 411
 412   return generic_force_reloc (fix);
 413 }
 414
 415 /* Return true if a relocation against a symbol may be replaced with
 416    a relocation against section+offset.  */
 417
 418 bfd_boolean
 419 xstormy16_fix_adjustable (fixP)
 420    fixS * fixP;
 421 {
 422   /* We need the symbol name for the VTABLE entries.  */
 423   if (fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT
 424       || fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
 425     return 0;
 426
 427   if (fixP->fx_r_type == BFD_RELOC_XSTORMY16_FPTR16)
 428     return 0;
 429
 430   return 1;
 431 }
 432
 433 /* This is a copy of gas_cgen_md_apply_fix3, with some enhancements to
 434    do various things that would not be valid for all ports.  */
 435
 436 void
 437 xstormy16_md_apply_fix3 (fixP, valueP, seg)
 438      fixS *   fixP;
 439      valueT * valueP;
 440      segT     seg ATTRIBUTE_UNUSED;
 441 {
 442   char *where = fixP->fx_frag->fr_literal + fixP->fx_where;
 443   valueT value = *valueP;
 444   /* Canonical name, since used a lot.  */
 445   CGEN_CPU_DESC cd = gas_cgen_cpu_desc;
 446
 447   /* md_cgen_lookup_reloc() will adjust this to compensate for where
 448      in the opcode the relocation happens, for pcrel relocations.  We
 449      have no other way of keeping track of what this offset needs to
 450      be.  */
 451   fixP->fx_addnumber = 0;
 452
 453   /* This port has pc-relative relocs and DIFF_EXPR_OK defined, so
 454      it must deal with turning a BFD_RELOC_{8,16,32,64} into a
 455      BFD_RELOC_*_PCREL for the case of
 456
 457         .word something-.
 458   */
 459   if (fixP->fx_pcrel)
 460     switch (fixP->fx_r_type)
 461       {
 462       case BFD_RELOC_8:
 463         fixP->fx_r_type = BFD_RELOC_8_PCREL;
 464         break;
 465       case BFD_RELOC_16:
 466         fixP->fx_r_type = BFD_RELOC_16_PCREL;
 467         break;
 468       case BFD_RELOC_32:
 469         fixP->fx_r_type = BFD_RELOC_32_PCREL;
 470         break;
 471       case BFD_RELOC_64:
 472         fixP->fx_r_type = BFD_RELOC_64_PCREL;
 473         break;
 474       default:
 475         break;
 476       }
 477
 478   if (fixP->fx_addsy == (symbolS *) NULL)
 479     fixP->fx_done = 1;
 480
 481   /* We don't actually support subtracting a symbol.  */
 482   if (fixP->fx_subsy != (symbolS *) NULL)
 483     as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex"));
 484
 485   if ((int) fixP->fx_r_type >= (int) BFD_RELOC_UNUSED)
 486     {
 487       int opindex = (int) fixP->fx_r_type - (int) BFD_RELOC_UNUSED;
 488       const CGEN_OPERAND *operand = cgen_operand_lookup_by_num (cd, opindex);
 489       const char *errmsg;
 490       bfd_reloc_code_real_type reloc_type;
 491       CGEN_FIELDS *fields = alloca (CGEN_CPU_SIZEOF_FIELDS (cd));
 492       const CGEN_INSN *insn = fixP->fx_cgen.insn;
 493
 494       /* If the reloc has been fully resolved finish the operand here.  */
 495       /* FIXME: This duplicates the capabilities of code in BFD.  */
 496       if (fixP->fx_done)
 497         {
 498           CGEN_CPU_SET_FIELDS_BITSIZE (cd) (fields, CGEN_INSN_BITSIZE (insn));
 499           CGEN_CPU_SET_VMA_OPERAND (cd) (cd, opindex, fields, (bfd_vma) value);
 500
 501 #if CGEN_INT_INSN_P
 502           {
 503             CGEN_INSN_INT insn_value =
 504               cgen_get_insn_value (cd, where, CGEN_INSN_BITSIZE (insn));
 505
 506             /* ??? 0 is passed for `pc'.  */
 507             errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields,
 508                                                    &insn_value, (bfd_vma) 0);
 509             cgen_put_insn_value (cd, where, CGEN_INSN_BITSIZE (insn),
 510                                  insn_value);
 511           }
 512 #else
 513           /* ??? 0 is passed for `pc'.  */
 514           errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields, where,
 515                                                  (bfd_vma) 0);
 516 #endif
 517           if (errmsg)
 518             as_bad_where (fixP->fx_file, fixP->fx_line, "%s", errmsg);
 519         }
 520
 521       if (fixP->fx_done)
 522         return;
 523
 524       /* The operand isn't fully resolved.  Determine a BFD reloc value
 525          based on the operand information and leave it to
 526          bfd_install_relocation.  Note that this doesn't work when
 527          !partial_inplace.  */
 528
 529       reloc_type = md_cgen_lookup_reloc (insn, operand, fixP);
 530       if (reloc_type != BFD_RELOC_NONE)
 531         {
 532           fixP->fx_r_type = reloc_type;
 533         }
 534       else
 535         {
 536           as_bad_where (fixP->fx_file, fixP->fx_line,
 537                         _("unresolved expression that must be resolved"));
 538           fixP->fx_done = 1;
 539           return;
 540         }
 541     }
 542   else if (fixP->fx_done)
 543     {
 544       /* We're finished with this fixup.  Install it because
 545          bfd_install_relocation won't be called to do it.  */
 546       switch (fixP->fx_r_type)
 547         {
 548         case BFD_RELOC_8:
 549           md_number_to_chars (where, value, 1);
 550           break;
 551         case BFD_RELOC_16:
 552           md_number_to_chars (where, value, 2);
 553           break;
 554         case BFD_RELOC_32:
 555           md_number_to_chars (where, value, 4);
 556           break;
 557         case BFD_RELOC_64:
 558           md_number_to_chars (where, value, 8);
 559           break;
 560         default:
 561           as_bad_where (fixP->fx_file, fixP->fx_line,
 562                         _("internal error: can't install fix for reloc type %d (`%s')"),
 563                         fixP->fx_r_type, bfd_get_reloc_code_name (fixP->fx_r_type));
 564           break;
 565         }
 566     }
 567   else
 568     {
 569       /* bfd_install_relocation will be called to finish things up.  */
 570     }
 571
 572   /* This is a RELA port.  Thus, it does not need to store a
 573      value if it is going to make a reloc.  What's more, when
 574      assembling a line like
 575
 576      .byte global-0x7f00
 577
 578      we'll get a spurious error message if we try to stuff 0x7f00 into
 579      the byte.  */
 580   if (! fixP->fx_done)
 581     *valueP = 0;
 582
 583   /* Tuck `value' away for use by tc_gen_reloc.
 584      See the comment describing fx_addnumber in write.h.
 585      This field is misnamed (or misused :-).  */
 586   fixP->fx_addnumber += value;
 587 }
 588
 589 \f
 590 /* Write a value out to the object file, using the appropriate endianness.  */
 591
 592 void
 593 md_number_to_chars (buf, val, n)
 594      char * buf;
 595      valueT val;
 596      int    n;
 597 {
 598   number_to_chars_littleendian (buf, val, n);
 599 }
 600
 601 /* Turn a string in input_line_pointer into a floating point constant of type
 602    type, and store the appropriate bytes in *litP.  The number of LITTLENUMS
 603    emitted is stored in *sizeP .  An error message is returned, or NULL on OK.
 604 */
 605
 606 /* Equal to MAX_PRECISION in atof-ieee.c */
 607 #define MAX_LITTLENUMS 6
 608
 609 char *
 610 md_atof (type, litP, sizeP)
 611      char   type;
 612      char * litP;
 613      int *  sizeP;
 614 {
 615   int              prec;
 616   LITTLENUM_TYPE   words [MAX_LITTLENUMS];
 617   LITTLENUM_TYPE   *wordP;
 618   char *           t;
 619
 620   switch (type)
 621     {
 622     case 'f':
 623     case 'F':
 624       prec = 2;
 625       break;
 626
 627     case 'd':
 628     case 'D':
 629       prec = 4;
 630       break;
 631
 632    /* FIXME: Some targets allow other format chars for bigger sizes here.  */
 633
 634     default:
 635       * sizeP = 0;
 636       return _("Bad call to md_atof()");
 637     }
 638
 639   t = atof_ieee (input_line_pointer, type, words);
 640   if (t)
 641     input_line_pointer = t;
 642   * sizeP = prec * sizeof (LITTLENUM_TYPE);
 643
 644   *sizeP = prec * sizeof (LITTLENUM_TYPE);
 645   /* This loops outputs the LITTLENUMs in REVERSE order; in accord with
 646      the littleendianness of the processor.  */
 647   for (wordP = words + prec - 1; prec--;)
 648     {
 649       md_number_to_chars (litP, (valueT) (*wordP--), sizeof (LITTLENUM_TYPE));
 650       litP += sizeof (LITTLENUM_TYPE);
 651     }
 652
 653   return 0;
 654 }