gas/config/tc-mt.c

   1 /* tc-mt.c -- Assembler for the Morpho Technologies mt .
   2    Copyright (C) 2005, 2006 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 "as.h"
  22 #include "dwarf2dbg.h"
  23 #include "subsegs.h"
  24 #include "symcat.h"
  25 #include "opcodes/mt-desc.h"
  26 #include "opcodes/mt-opc.h"
  27 #include "cgen.h"
  28 #include "elf/common.h"
  29 #include "elf/mt.h"
  30 #include "libbfd.h"
  31
  32 /* Structure to hold all of the different components
  33    describing an individual instruction.  */
  34 typedef struct
  35 {
  36   const CGEN_INSN *     insn;
  37   const CGEN_INSN *     orig_insn;
  38   CGEN_FIELDS           fields;
  39 #if CGEN_INT_INSN_P
  40   CGEN_INSN_INT         buffer [1];
  41 #define INSN_VALUE(buf) (*(buf))
  42 #else
  43   unsigned char         buffer [CGEN_MAX_INSN_SIZE];
  44 #define INSN_VALUE(buf) (buf)
  45 #endif
  46   char *                addr;
  47   fragS *               frag;
  48   int                   num_fixups;
  49   fixS *                fixups [GAS_CGEN_MAX_FIXUPS];
  50   int                   indices [MAX_OPERAND_INSTANCES];
  51 }
  52 mt_insn;
  53
  54
  55 const char comment_chars[]        = ";";
  56 const char line_comment_chars[]   = "#";
  57 const char line_separator_chars[] = "";
  58 const char EXP_CHARS[]            = "eE";
  59 const char FLT_CHARS[]            = "dD";
  60
  61 /* The target specific pseudo-ops which we support.  */
  62 const pseudo_typeS md_pseudo_table[] =
  63 {
  64     { "word",   cons,                   4 },
  65     { NULL,     NULL,                   0 }
  66 };
  67
  68 \f
  69
  70 static int no_scheduling_restrictions = 0;
  71
  72 struct option md_longopts[] =
  73 {
  74 #define OPTION_NO_SCHED_REST    (OPTION_MD_BASE)
  75   { "nosched",     no_argument, NULL, OPTION_NO_SCHED_REST },
  76 #define OPTION_MARCH            (OPTION_MD_BASE + 1)
  77   { "march", required_argument, NULL, OPTION_MARCH},
  78   { NULL,          no_argument, NULL, 0 },
  79 };
  80 size_t md_longopts_size = sizeof (md_longopts);
  81
  82 const char * md_shortopts = "";
  83
  84 /* Mach selected from command line.  */
  85 static int mt_mach = bfd_mach_ms1;
  86 static unsigned mt_mach_bitmask = 1 << MACH_MS1;
  87
  88 /* Flags to set in the elf header */
  89 static flagword mt_flags = EF_MT_CPU_MRISC;
  90
  91 /* The architecture to use.  */
  92 enum mt_architectures
  93   {
  94     ms1_64_001,
  95     ms1_16_002,
  96     ms1_16_003,
  97     ms2
  98   };
  99
 100 /* MT architecture we are using for this output file.  */
 101 static enum mt_architectures mt_arch = ms1_16_002;
 102
 103 int
 104 md_parse_option (int c ATTRIBUTE_UNUSED, char * arg)
 105 {
 106   switch (c)
 107     {
 108     case OPTION_MARCH:
 109       if (strcmp (arg, "ms1-64-001") == 0)
 110         {
 111           mt_flags = (mt_flags & ~EF_MT_CPU_MASK) | EF_MT_CPU_MRISC;
 112           mt_mach = bfd_mach_ms1;
 113           mt_mach_bitmask = 1 << MACH_MS1;
 114           mt_arch = ms1_64_001;
 115         }
 116       else if (strcmp (arg, "ms1-16-002") == 0)
 117         {
 118           mt_flags = (mt_flags & ~EF_MT_CPU_MASK) | EF_MT_CPU_MRISC;
 119           mt_mach = bfd_mach_ms1;
 120           mt_mach_bitmask = 1 << MACH_MS1;
 121           mt_arch = ms1_16_002;
 122         }
 123       else if (strcmp (arg, "ms1-16-003") == 0)
 124         {
 125           mt_flags = (mt_flags & ~EF_MT_CPU_MASK) | EF_MT_CPU_MRISC2;
 126           mt_mach = bfd_mach_mrisc2;
 127           mt_mach_bitmask = 1 << MACH_MS1_003;
 128           mt_arch = ms1_16_003;
 129         }
 130       else if (strcmp (arg, "ms2") == 0)
 131         {
 132           mt_flags = (mt_flags & ~EF_MT_CPU_MASK) | EF_MT_CPU_MS2;
 133           mt_mach = bfd_mach_mrisc2;
 134           mt_mach_bitmask = 1 << MACH_MS2;
 135           mt_arch = ms2;
 136         }
 137     case OPTION_NO_SCHED_REST:
 138       no_scheduling_restrictions = 1;
 139       break;
 140     default:
 141       return 0;
 142     }
 143
 144   return 1;
 145 }
 146
 147
 148 void
 149 md_show_usage (FILE * stream)
 150 {
 151   fprintf (stream, _("MT specific command line options:\n"));
 152   fprintf (stream, _("  -march=ms1-64-001         allow ms1-64-001 instructions\n"));
 153   fprintf (stream, _("  -march=ms1-16-002         allow ms1-16-002 instructions (default)\n"));
 154   fprintf (stream, _("  -march=ms1-16-003         allow ms1-16-003 instructions\n"));
 155   fprintf (stream, _("  -march=ms2                allow ms2 instructions \n"));
 156   fprintf (stream, _("  -nosched                  disable scheduling restrictions\n"));
 157 }
 158
 159 \f
 160 void
 161 md_begin (void)
 162 {
 163   /* Initialize the `cgen' interface.  */
 164
 165   /* Set the machine number and endian.  */
 166   gas_cgen_cpu_desc = mt_cgen_cpu_open (CGEN_CPU_OPEN_MACHS, mt_mach_bitmask,
 167                                         CGEN_CPU_OPEN_ENDIAN,
 168                                         CGEN_ENDIAN_BIG,
 169                                         CGEN_CPU_OPEN_END);
 170   mt_cgen_init_asm (gas_cgen_cpu_desc);
 171
 172   /* This is a callback from cgen to gas to parse operands.  */
 173   cgen_set_parse_operand_fn (gas_cgen_cpu_desc, gas_cgen_parse_operand);
 174
 175   /* Set the ELF flags if desired. */
 176   if (mt_flags)
 177     bfd_set_private_flags (stdoutput, mt_flags);
 178
 179   /* Set the machine type.  */
 180   bfd_default_set_arch_mach (stdoutput, bfd_arch_mt, mt_mach);
 181 }
 182
 183 void
 184 md_assemble (char * str)
 185 {
 186   static long delayed_load_register = 0;
 187   static long prev_delayed_load_register = 0;
 188   static int last_insn_had_delay_slot = 0;
 189   static int last_insn_in_noncond_delay_slot = 0;
 190   static int last_insn_has_load_delay = 0;
 191   static int last_insn_was_memory_access = 0;
 192   static int last_insn_was_io_insn = 0;
 193   static int last_insn_was_arithmetic_or_logic = 0;
 194   static int last_insn_was_branch_insn = 0;
 195   static int last_insn_was_conditional_branch_insn = 0;
 196
 197   mt_insn insn;
 198   char * errmsg;
 199
 200   /* Initialize GAS's cgen interface for a new instruction.  */
 201   gas_cgen_init_parse ();
 202
 203   insn.insn = mt_cgen_assemble_insn
 204       (gas_cgen_cpu_desc, str, & insn.fields, insn.buffer, & errmsg);
 205
 206   if (!insn.insn)
 207     {
 208       as_bad ("%s", errmsg);
 209       return;
 210     }
 211
 212   /* Doesn't really matter what we pass for RELAX_P here.  */
 213   gas_cgen_finish_insn (insn.insn, insn.buffer,
 214                         CGEN_FIELDS_BITSIZE (& insn.fields), 1, NULL);
 215
 216
 217   /* Handle Scheduling Restrictions.  */
 218   if (!no_scheduling_restrictions)
 219     {
 220       /* Detect consecutive Memory Accesses.  */
 221       if (last_insn_was_memory_access
 222           && CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_MEMORY_ACCESS)
 223           && mt_mach == ms1_64_001)
 224         as_warn (_("instruction %s may not follow another memory access instruction."),
 225                  CGEN_INSN_NAME (insn.insn));
 226
 227       /* Detect consecutive I/O Instructions.  */
 228       else if (last_insn_was_io_insn
 229                && CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_IO_INSN))
 230         as_warn (_("instruction %s may not follow another I/O instruction."),
 231                  CGEN_INSN_NAME (insn.insn));
 232
 233       /* Detect consecutive branch instructions.  */
 234       else if (last_insn_was_branch_insn
 235                && CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_BR_INSN))
 236         as_warn (_("%s may not occupy the delay slot of another branch insn."),
 237                  CGEN_INSN_NAME (insn.insn));
 238
 239       /* Detect data dependencies on delayed loads: memory and input insns.  */
 240       if (last_insn_has_load_delay && delayed_load_register)
 241         {
 242           if (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR1)
 243               && insn.fields.f_sr1 == delayed_load_register)
 244             as_warn (_("operand references R%ld of previous load."),
 245                      insn.fields.f_sr1);
 246
 247           if (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR2)
 248               && insn.fields.f_sr2 == delayed_load_register)
 249             as_warn (_("operand references R%ld of previous load."),
 250                      insn.fields.f_sr2);
 251         }
 252
 253       /* Detect JAL/RETI hazard */
 254       if (mt_mach == ms2
 255           && CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_JAL_HAZARD))
 256         {
 257           if ((CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR1)
 258                && insn.fields.f_sr1 == delayed_load_register)
 259               || (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR2)
 260                   && insn.fields.f_sr2 == delayed_load_register))
 261             as_warn (_("operand references R%ld of previous instrutcion."),
 262                      delayed_load_register);
 263           else if ((CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR1)
 264                     && insn.fields.f_sr1 == prev_delayed_load_register)
 265                    || (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR2)
 266                        && insn.fields.f_sr2 == prev_delayed_load_register))
 267             as_warn (_("operand references R%ld of instructcion before previous."),
 268                      prev_delayed_load_register);
 269         }
 270
 271       /* Detect data dependency between conditional branch instruction
 272          and an immediately preceding arithmetic or logical instruction.  */
 273       if (last_insn_was_arithmetic_or_logic
 274           && !last_insn_in_noncond_delay_slot
 275           && (delayed_load_register != 0)
 276           && CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_BR_INSN)
 277           && mt_arch == ms1_64_001)
 278         {
 279           if (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR1)
 280               && insn.fields.f_sr1 == delayed_load_register)
 281             as_warn (_("conditional branch or jal insn's operand references R%ld of previous arithmetic or logic insn."),
 282                      insn.fields.f_sr1);
 283
 284           if (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR2)
 285               && insn.fields.f_sr2 == delayed_load_register)
 286             as_warn (_("conditional branch or jal insn's operand references R%ld of previous arithmetic or logic insn."),
 287                      insn.fields.f_sr2);
 288         }
 289     }
 290
 291   /* Keep track of details of this insn for processing next insn.  */
 292   last_insn_in_noncond_delay_slot = last_insn_was_branch_insn
 293     && !last_insn_was_conditional_branch_insn;
 294
 295   last_insn_had_delay_slot =
 296     CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_DELAY_SLOT);
 297
 298   last_insn_has_load_delay =
 299     CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_LOAD_DELAY);
 300
 301   last_insn_was_memory_access =
 302     CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_MEMORY_ACCESS);
 303
 304   last_insn_was_io_insn =
 305     CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_IO_INSN);
 306
 307   last_insn_was_arithmetic_or_logic =
 308     CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_AL_INSN);
 309
 310   last_insn_was_branch_insn =
 311     CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_BR_INSN);
 312
 313   last_insn_was_conditional_branch_insn =
 314   CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_BR_INSN)
 315     && CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRSR2);
 316
 317   prev_delayed_load_register = delayed_load_register;
 318
 319   if (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRDR))
 320      delayed_load_register = insn.fields.f_dr;
 321   else if (CGEN_INSN_ATTR_VALUE (insn.insn, CGEN_INSN_USES_FRDRRR))
 322      delayed_load_register = insn.fields.f_drrr;
 323   else  /* Insns has no destination register.  */
 324      delayed_load_register = 0;
 325
 326   /* Generate dwarf2 line numbers.  */
 327   dwarf2_emit_insn (4);
 328 }
 329
 330 valueT
 331 md_section_align (segT segment, valueT size)
 332 {
 333   int align = bfd_get_section_alignment (stdoutput, segment);
 334
 335   return ((size + (1 << align) - 1) & (-1 << align));
 336 }
 337
 338 symbolS *
 339 md_undefined_symbol (char * name ATTRIBUTE_UNUSED)
 340 {
 341     return NULL;
 342 }
 343 \f
 344 int
 345 md_estimate_size_before_relax (fragS * fragP ATTRIBUTE_UNUSED,
 346                                segT    segment ATTRIBUTE_UNUSED)
 347 {
 348   as_fatal (_("md_estimate_size_before_relax\n"));
 349   return 1;
 350 }
 351
 352 /* *fragP has been relaxed to its final size, and now needs to have
 353    the bytes inside it modified to conform to the new size.
 354
 355    Called after relaxation is finished.
 356    fragP->fr_type == rs_machine_dependent.
 357    fragP->fr_subtype is the subtype of what the address relaxed to.  */
 358
 359 void
 360 md_convert_frag (bfd   * abfd  ATTRIBUTE_UNUSED,
 361                  segT    sec   ATTRIBUTE_UNUSED,
 362                  fragS * fragP ATTRIBUTE_UNUSED)
 363 {
 364 }
 365
 366 \f
 367 /* Functions concerning relocs.  */
 368
 369 long
 370 md_pcrel_from_section (fixS *fixP, segT sec)
 371 {
 372   if (fixP->fx_addsy != (symbolS *) NULL
 373       && (!S_IS_DEFINED (fixP->fx_addsy)
 374           || S_GET_SEGMENT (fixP->fx_addsy) != sec))
 375     /* The symbol is undefined (or is defined but not in this section).
 376        Let the linker figure it out.  */
 377     return 0;
 378
 379   /* Return the address of the opcode - cgen adjusts for opcode size
 380      itself, to be consistent with the disassembler, which must do
 381      so.  */
 382   return fixP->fx_where + fixP->fx_frag->fr_address;
 383 }
 384
 385
 386 /* Return the bfd reloc type for OPERAND of INSN at fixup FIXP.
 387    Returns BFD_RELOC_NONE if no reloc type can be found.
 388    *FIXP may be modified if desired.  */
 389
 390 bfd_reloc_code_real_type
 391 md_cgen_lookup_reloc (const CGEN_INSN *    insn     ATTRIBUTE_UNUSED,
 392                       const CGEN_OPERAND * operand,
 393                       fixS *               fixP     ATTRIBUTE_UNUSED)
 394 {
 395   bfd_reloc_code_real_type result;
 396
 397   result = BFD_RELOC_NONE;
 398
 399   switch (operand->type)
 400     {
 401     case MT_OPERAND_IMM16O:
 402       result = BFD_RELOC_16_PCREL;
 403       fixP->fx_pcrel = 1;
 404       /* fixP->fx_no_overflow = 1; */
 405       break;
 406     case MT_OPERAND_IMM16:
 407     case MT_OPERAND_IMM16Z:
 408       /* These may have been processed at parse time.  */
 409       if (fixP->fx_cgen.opinfo != 0)
 410         result = fixP->fx_cgen.opinfo;
 411       fixP->fx_no_overflow = 1;
 412       break;
 413     case MT_OPERAND_LOOPSIZE:
 414       result = BFD_RELOC_MT_PCINSN8;
 415       fixP->fx_pcrel = 1;
 416       /* Adjust for the delay slot, which is not part of the loop  */
 417       fixP->fx_offset -= 8;
 418       break;
 419     default:
 420       result = BFD_RELOC_NONE;
 421       break;
 422     }
 423
 424   return result;
 425 }
 426
 427 /* Write a value out to the object file, using the appropriate endianness.  */
 428
 429 void
 430 md_number_to_chars (char * buf, valueT val, int n)
 431 {
 432   number_to_chars_bigendian (buf, val, n);
 433 }
 434
 435 /* Turn a string in input_line_pointer into a floating point constant of type
 436    type, and store the appropriate bytes in *litP.  The number of LITTLENUMS
 437    emitted is stored in *sizeP .  An error message is returned, or NULL on OK.  */
 438
 439 /* Equal to MAX_PRECISION in atof-ieee.c.  */
 440 #define MAX_LITTLENUMS 6
 441
 442 char *
 443 md_atof (type, litP, sizeP)
 444      char   type;
 445      char * litP;
 446      int *  sizeP;
 447 {
 448   int              prec;
 449   LITTLENUM_TYPE   words [MAX_LITTLENUMS];
 450   LITTLENUM_TYPE * wordP;
 451   char *           t;
 452
 453   switch (type)
 454     {
 455     case 'f':
 456     case 'F':
 457     case 's':
 458     case 'S':
 459       prec = 2;
 460       break;
 461
 462     case 'd':
 463     case 'D':
 464     case 'r':
 465     case 'R':
 466       prec = 4;
 467       break;
 468
 469    /* FIXME: Some targets allow other format chars for bigger sizes here.  */
 470
 471     default:
 472       * sizeP = 0;
 473       return _("Bad call to md_atof()");
 474     }
 475
 476   t = atof_ieee (input_line_pointer, type, words);
 477   if (t)
 478     input_line_pointer = t;
 479   * sizeP = prec * sizeof (LITTLENUM_TYPE);
 480
 481   /* This loops outputs the LITTLENUMs in REVERSE order;
 482      in accord with the mt endianness.  */
 483   for (wordP = words; prec--;)
 484     {
 485       md_number_to_chars (litP, (valueT) (*wordP++), sizeof (LITTLENUM_TYPE));
 486       litP += sizeof (LITTLENUM_TYPE);
 487     }
 488
 489   return 0;
 490 }
 491
 492 /* See whether we need to force a relocation into the output file.  */
 493
 494 int
 495 mt_force_relocation (fixS * fixp ATTRIBUTE_UNUSED)
 496 {
 497   return 0;
 498 }
 499
 500 void
 501 mt_apply_fix (fixS *fixP, valueT *valueP, segT seg)
 502 {
 503   if ((fixP->fx_pcrel != 0) && (fixP->fx_r_type == BFD_RELOC_32))
 504     fixP->fx_r_type = BFD_RELOC_32_PCREL;
 505
 506   gas_cgen_md_apply_fix (fixP, valueP, seg);
 507 }
 508
 509 bfd_boolean
 510 mt_fix_adjustable (fixS * fixP)
 511 {
 512   bfd_reloc_code_real_type reloc_type;
 513
 514   if ((int) fixP->fx_r_type >= (int) BFD_RELOC_UNUSED)
 515     {
 516       const CGEN_INSN *insn = NULL;
 517       int opindex = (int) fixP->fx_r_type - (int) BFD_RELOC_UNUSED;
 518       const CGEN_OPERAND *operand;
 519
 520       operand = cgen_operand_lookup_by_num(gas_cgen_cpu_desc, opindex);
 521       reloc_type = md_cgen_lookup_reloc (insn, operand, fixP);
 522     }
 523   else
 524     reloc_type = fixP->fx_r_type;
 525
 526   if (fixP->fx_addsy == NULL)
 527     return TRUE;
 528
 529   /* Prevent all adjustments to global symbols.  */
 530   if (S_IS_EXTERNAL (fixP->fx_addsy))
 531     return FALSE;
 532
 533   if (S_IS_WEAK (fixP->fx_addsy))
 534     return FALSE;
 535
 536   return 1;
 537 }