opcodes/cgen-asm.in

   1 /* Assembler interface for targets using CGEN. -*- C -*-
   2    CGEN: Cpu tools GENerator
   3
   4    THIS FILE IS MACHINE GENERATED WITH CGEN.
   5    - the resultant file is machine generated, cgen-asm.in isn't
   6
   7    Copyright (C) 1996-2019 Free Software Foundation, Inc.
   8
   9    This file is part of libopcodes.
  10
  11    This library 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, or (at your option)
  14    any later version.
  15
  16    It is distributed in the hope that it will be useful, but WITHOUT
  17    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  18    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  19    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, write to the Free Software Foundation, Inc.,
  23    51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
  24
  25
  26 /* ??? Eventually more and more of this stuff can go to cpu-independent files.
  27    Keep that in mind.  */
  28
  29 #include "sysdep.h"
  30 #include <stdio.h>
  31 #include "ansidecl.h"
  32 #include "bfd.h"
  33 #include "symcat.h"
  34 #include "@prefix@-desc.h"
  35 #include "@prefix@-opc.h"
  36 #include "opintl.h"
  37 #include "xregex.h"
  38 #include "libiberty.h"
  39 #include "safe-ctype.h"
  40
  41 #undef  min
  42 #define min(a,b) ((a) < (b) ? (a) : (b))
  43 #undef  max
  44 #define max(a,b) ((a) > (b) ? (a) : (b))
  45
  46 static const char * parse_insn_normal
  47   (CGEN_CPU_DESC, const CGEN_INSN *, const char **, CGEN_FIELDS *);
  48 \f
  49 /* -- assembler routines inserted here.  */
  50 \f
  51
  52 /* Regex construction routine.
  53
  54    This translates an opcode syntax string into a regex string,
  55    by replacing any non-character syntax element (such as an
  56    opcode) with the pattern '.*'
  57
  58    It then compiles the regex and stores it in the opcode, for
  59    later use by @arch@_cgen_assemble_insn
  60
  61    Returns NULL for success, an error message for failure.  */
  62
  63 char *
  64 @arch@_cgen_build_insn_regex (CGEN_INSN *insn)
  65 {
  66   CGEN_OPCODE *opc = (CGEN_OPCODE *) CGEN_INSN_OPCODE (insn);
  67   const char *mnem = CGEN_INSN_MNEMONIC (insn);
  68   char rxbuf[CGEN_MAX_RX_ELEMENTS];
  69   char *rx = rxbuf;
  70   const CGEN_SYNTAX_CHAR_TYPE *syn;
  71   int reg_err;
  72
  73   syn = CGEN_SYNTAX_STRING (CGEN_OPCODE_SYNTAX (opc));
  74
  75   /* Mnemonics come first in the syntax string.  */
  76   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
  77     return _("missing mnemonic in syntax string");
  78   ++syn;
  79
  80   /* Generate a case sensitive regular expression that emulates case
  81      insensitive matching in the "C" locale.  We cannot generate a case
  82      insensitive regular expression because in Turkish locales, 'i' and 'I'
  83      are not equal modulo case conversion.  */
  84
  85   /* Copy the literal mnemonic out of the insn.  */
  86   for (; *mnem; mnem++)
  87     {
  88       char c = *mnem;
  89
  90       if (ISALPHA (c))
  91         {
  92           *rx++ = '[';
  93           *rx++ = TOLOWER (c);
  94           *rx++ = TOUPPER (c);
  95           *rx++ = ']';
  96         }
  97       else
  98         *rx++ = c;
  99     }
 100
 101   /* Copy any remaining literals from the syntax string into the rx.  */
 102   for(; * syn != 0 && rx <= rxbuf + (CGEN_MAX_RX_ELEMENTS - 7 - 4); ++syn)
 103     {
 104       if (CGEN_SYNTAX_CHAR_P (* syn))
 105         {
 106           char c = CGEN_SYNTAX_CHAR (* syn);
 107
 108           switch (c)
 109             {
 110               /* Escape any regex metacharacters in the syntax.  */
 111             case '.': case '[': case '\\':
 112             case '*': case '^': case '$':
 113
 114 #ifdef CGEN_ESCAPE_EXTENDED_REGEX
 115             case '?': case '{': case '}':
 116             case '(': case ')': case '*':
 117             case '|': case '+': case ']':
 118 #endif
 119               *rx++ = '\\';
 120               *rx++ = c;
 121               break;
 122
 123             default:
 124               if (ISALPHA (c))
 125                 {
 126                   *rx++ = '[';
 127                   *rx++ = TOLOWER (c);
 128                   *rx++ = TOUPPER (c);
 129                   *rx++ = ']';
 130                 }
 131               else
 132                 *rx++ = c;
 133               break;
 134             }
 135         }
 136       else
 137         {
 138           /* Replace non-syntax fields with globs.  */
 139           *rx++ = '.';
 140           *rx++ = '*';
 141         }
 142     }
 143
 144   /* Trailing whitespace ok.  */
 145   * rx++ = '[';
 146   * rx++ = ' ';
 147   * rx++ = '\t';
 148   * rx++ = ']';
 149   * rx++ = '*';
 150
 151   /* But anchor it after that.  */
 152   * rx++ = '$';
 153   * rx = '\0';
 154
 155   CGEN_INSN_RX (insn) = xmalloc (sizeof (regex_t));
 156   reg_err = regcomp ((regex_t *) CGEN_INSN_RX (insn), rxbuf, REG_NOSUB);
 157
 158   if (reg_err == 0)
 159     return NULL;
 160   else
 161     {
 162       static char msg[80];
 163
 164       regerror (reg_err, (regex_t *) CGEN_INSN_RX (insn), msg, 80);
 165       regfree ((regex_t *) CGEN_INSN_RX (insn));
 166       free (CGEN_INSN_RX (insn));
 167       (CGEN_INSN_RX (insn)) = NULL;
 168       return msg;
 169     }
 170 }
 171
 172 \f
 173 /* Default insn parser.
 174
 175    The syntax string is scanned and operands are parsed and stored in FIELDS.
 176    Relocs are queued as we go via other callbacks.
 177
 178    ??? Note that this is currently an all-or-nothing parser.  If we fail to
 179    parse the instruction, we return 0 and the caller will start over from
 180    the beginning.  Backtracking will be necessary in parsing subexpressions,
 181    but that can be handled there.  Not handling backtracking here may get
 182    expensive in the case of the m68k.  Deal with later.
 183
 184    Returns NULL for success, an error message for failure.  */
 185
 186 static const char *
 187 parse_insn_normal (CGEN_CPU_DESC cd,
 188                    const CGEN_INSN *insn,
 189                    const char **strp,
 190                    CGEN_FIELDS *fields)
 191 {
 192   /* ??? Runtime added insns not handled yet.  */
 193   const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn);
 194   const char *str = *strp;
 195   const char *errmsg;
 196   const char *p;
 197   const CGEN_SYNTAX_CHAR_TYPE * syn;
 198 #ifdef CGEN_MNEMONIC_OPERANDS
 199   /* FIXME: wip */
 200   int past_opcode_p;
 201 #endif
 202
 203   /* For now we assume the mnemonic is first (there are no leading operands).
 204      We can parse it without needing to set up operand parsing.
 205      GAS's input scrubber will ensure mnemonics are lowercase, but we may
 206      not be called from GAS.  */
 207   p = CGEN_INSN_MNEMONIC (insn);
 208   while (*p && TOLOWER (*p) == TOLOWER (*str))
 209     ++p, ++str;
 210
 211   if (* p)
 212     return _("unrecognized instruction");
 213
 214 #ifndef CGEN_MNEMONIC_OPERANDS
 215   if (* str && ! ISSPACE (* str))
 216     return _("unrecognized instruction");
 217 #endif
 218
 219   CGEN_INIT_PARSE (cd);
 220   cgen_init_parse_operand (cd);
 221 #ifdef CGEN_MNEMONIC_OPERANDS
 222   past_opcode_p = 0;
 223 #endif
 224
 225   /* We don't check for (*str != '\0') here because we want to parse
 226      any trailing fake arguments in the syntax string.  */
 227   syn = CGEN_SYNTAX_STRING (syntax);
 228
 229   /* Mnemonics come first for now, ensure valid string.  */
 230   if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
 231     abort ();
 232
 233   ++syn;
 234
 235   while (* syn != 0)
 236     {
 237       /* Non operand chars must match exactly.  */
 238       if (CGEN_SYNTAX_CHAR_P (* syn))
 239         {
 240           /* FIXME: While we allow for non-GAS callers above, we assume the
 241              first char after the mnemonic part is a space.  */
 242           /* FIXME: We also take inappropriate advantage of the fact that
 243              GAS's input scrubber will remove extraneous blanks.  */
 244           if (TOLOWER (*str) == TOLOWER (CGEN_SYNTAX_CHAR (* syn)))
 245             {
 246 #ifdef CGEN_MNEMONIC_OPERANDS
 247               if (CGEN_SYNTAX_CHAR(* syn) == ' ')
 248                 past_opcode_p = 1;
 249 #endif
 250               ++ syn;
 251               ++ str;
 252             }
 253           else if (*str)
 254             {
 255               /* Syntax char didn't match.  Can't be this insn.  */
 256               static char msg [80];
 257
 258               /* xgettext:c-format */
 259               sprintf (msg, _("syntax error (expected char `%c', found `%c')"),
 260                        CGEN_SYNTAX_CHAR(*syn), *str);
 261               return msg;
 262             }
 263           else
 264             {
 265               /* Ran out of input.  */
 266               static char msg [80];
 267
 268               /* xgettext:c-format */
 269               sprintf (msg, _("syntax error (expected char `%c', found end of instruction)"),
 270                        CGEN_SYNTAX_CHAR(*syn));
 271               return msg;
 272             }
 273           continue;
 274         }
 275
 276 #ifdef CGEN_MNEMONIC_OPERANDS
 277       (void) past_opcode_p;
 278 #endif
 279       /* We have an operand of some sort.  */
 280       errmsg = cd->parse_operand (cd, CGEN_SYNTAX_FIELD (*syn), &str, fields);
 281       if (errmsg)
 282         return errmsg;
 283
 284       /* Done with this operand, continue with next one.  */
 285       ++ syn;
 286     }
 287
 288   /* If we're at the end of the syntax string, we're done.  */
 289   if (* syn == 0)
 290     {
 291       /* FIXME: For the moment we assume a valid `str' can only contain
 292          blanks now.  IE: We needn't try again with a longer version of
 293          the insn and it is assumed that longer versions of insns appear
 294          before shorter ones (eg: lsr r2,r3,1 vs lsr r2,r3).  */
 295       while (ISSPACE (* str))
 296         ++ str;
 297
 298       if (* str != '\0')
 299         return _("junk at end of line"); /* FIXME: would like to include `str' */
 300
 301       return NULL;
 302     }
 303
 304   /* We couldn't parse it.  */
 305   return _("unrecognized instruction");
 306 }
 307 \f
 308 /* Main entry point.
 309    This routine is called for each instruction to be assembled.
 310    STR points to the insn to be assembled.
 311    We assume all necessary tables have been initialized.
 312    The assembled instruction, less any fixups, is stored in BUF.
 313    Remember that if CGEN_INT_INSN_P then BUF is an int and thus the value
 314    still needs to be converted to target byte order, otherwise BUF is an array
 315    of bytes in target byte order.
 316    The result is a pointer to the insn's entry in the opcode table,
 317    or NULL if an error occured (an error message will have already been
 318    printed).
 319
 320    Note that when processing (non-alias) macro-insns,
 321    this function recurses.
 322
 323    ??? It's possible to make this cpu-independent.
 324    One would have to deal with a few minor things.
 325    At this point in time doing so would be more of a curiosity than useful
 326    [for example this file isn't _that_ big], but keeping the possibility in
 327    mind helps keep the design clean.  */
 328
 329 const CGEN_INSN *
 330 @arch@_cgen_assemble_insn (CGEN_CPU_DESC cd,
 331                            const char *str,
 332                            CGEN_FIELDS *fields,
 333                            CGEN_INSN_BYTES_PTR buf,
 334                            char **errmsg)
 335 {
 336   const char *start;
 337   CGEN_INSN_LIST *ilist;
 338   const char *parse_errmsg = NULL;
 339   const char *insert_errmsg = NULL;
 340   int recognized_mnemonic = 0;
 341
 342   /* Skip leading white space.  */
 343   while (ISSPACE (* str))
 344     ++ str;
 345
 346   /* The instructions are stored in hashed lists.
 347      Get the first in the list.  */
 348   ilist = CGEN_ASM_LOOKUP_INSN (cd, str);
 349
 350   /* Keep looking until we find a match.  */
 351   start = str;
 352   for ( ; ilist != NULL ; ilist = CGEN_ASM_NEXT_INSN (ilist))
 353     {
 354       const CGEN_INSN *insn = ilist->insn;
 355       recognized_mnemonic = 1;
 356
 357 #ifdef CGEN_VALIDATE_INSN_SUPPORTED
 358       /* Not usually needed as unsupported opcodes
 359          shouldn't be in the hash lists.  */
 360       /* Is this insn supported by the selected cpu?  */
 361       if (! @arch@_cgen_insn_supported (cd, insn))
 362         continue;
 363 #endif
 364       /* If the RELAXED attribute is set, this is an insn that shouldn't be
 365          chosen immediately.  Instead, it is used during assembler/linker
 366          relaxation if possible.  */
 367       if (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXED) != 0)
 368         continue;
 369
 370       str = start;
 371
 372       /* Skip this insn if str doesn't look right lexically.  */
 373       if (CGEN_INSN_RX (insn) != NULL &&
 374           regexec ((regex_t *) CGEN_INSN_RX (insn), str, 0, NULL, 0) == REG_NOMATCH)
 375         continue;
 376
 377       /* Allow parse/insert handlers to obtain length of insn.  */
 378       CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn);
 379
 380       parse_errmsg = CGEN_PARSE_FN (cd, insn) (cd, insn, & str, fields);
 381       if (parse_errmsg != NULL)
 382         continue;
 383
 384       /* ??? 0 is passed for `pc'.  */
 385       insert_errmsg = CGEN_INSERT_FN (cd, insn) (cd, insn, fields, buf,
 386                                                  (bfd_vma) 0);
 387       if (insert_errmsg != NULL)
 388         continue;
 389
 390       /* It is up to the caller to actually output the insn and any
 391          queued relocs.  */
 392       return insn;
 393     }
 394
 395   {
 396     static char errbuf[150];
 397     const char *tmp_errmsg;
 398 #ifdef CGEN_VERBOSE_ASSEMBLER_ERRORS
 399 #define be_verbose 1
 400 #else
 401 #define be_verbose 0
 402 #endif
 403
 404     if (be_verbose)
 405       {
 406         /* If requesting verbose error messages, use insert_errmsg.
 407            Failing that, use parse_errmsg.  */
 408         tmp_errmsg = (insert_errmsg ? insert_errmsg :
 409                       parse_errmsg ? parse_errmsg :
 410                       recognized_mnemonic ?
 411                       _("unrecognized form of instruction") :
 412                       _("unrecognized instruction"));
 413
 414         if (strlen (start) > 50)
 415           /* xgettext:c-format */
 416           sprintf (errbuf, "%s `%.50s...'", tmp_errmsg, start);
 417         else
 418           /* xgettext:c-format */
 419           sprintf (errbuf, "%s `%.50s'", tmp_errmsg, start);
 420       }
 421     else
 422       {
 423         if (strlen (start) > 50)
 424           /* xgettext:c-format */
 425           sprintf (errbuf, _("bad instruction `%.50s...'"), start);
 426         else
 427           /* xgettext:c-format */
 428           sprintf (errbuf, _("bad instruction `%.50s'"), start);
 429       }
 430
 431     *errmsg = errbuf;
 432     return NULL;
 433   }
 434 }