gas/config/tc-avr.c

   1 /* tc-avr.c -- Assembler code for the ATMEL AVR
   2
   3    Copyright 1999, 2000, 2001, 2002, 2004 Free Software Foundation, Inc.
   4    Contributed by Denis Chertykov <denisc@overta.ru>
   5
   6    This file is part of GAS, the GNU Assembler.
   7
   8    GAS is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2, or (at your option)
  11    any later version.
  12
  13    GAS is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GAS; see the file COPYING.  If not, write to
  20    the Free Software Foundation, 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #include <stdio.h>
  24 #include "as.h"
  25 #include "safe-ctype.h"
  26 #include "subsegs.h"
  27
  28 struct avr_opcodes_s
  29 {
  30   char *name;
  31   char *constraints;
  32   int insn_size;                /* In words.  */
  33   int isa;
  34   unsigned int bin_opcode;
  35 };
  36
  37 #define AVR_INSN(NAME, CONSTR, OPCODE, SIZE, ISA, BIN) \
  38 {#NAME, CONSTR, SIZE, ISA, BIN},
  39
  40 struct avr_opcodes_s avr_opcodes[] =
  41 {
  42   #include "opcode/avr.h"
  43   {NULL, NULL, 0, 0, 0}
  44 };
  45
  46 const char comment_chars[] = ";";
  47 const char line_comment_chars[] = "#";
  48 const char line_separator_chars[] = "$";
  49
  50 const char *md_shortopts = "m:";
  51 struct mcu_type_s
  52 {
  53   char *name;
  54   int isa;
  55   int mach;
  56 };
  57
  58 /* XXX - devices that don't seem to exist (renamed, replaced with larger
  59    ones, or planned but never produced), left here for compatibility.
  60    TODO: hide them in show_mcu_list output?  */
  61
  62 static struct mcu_type_s mcu_types[] =
  63 {
  64   {"avr1",      AVR_ISA_TINY1,    bfd_mach_avr1},
  65   {"avr2",      AVR_ISA_TINY2,    bfd_mach_avr2},
  66   {"avr3",      AVR_ISA_M103,     bfd_mach_avr3},
  67   {"avr4",      AVR_ISA_M8,       bfd_mach_avr4},
  68   {"avr5",      AVR_ISA_ALL,      bfd_mach_avr5},
  69   {"at90s1200", AVR_ISA_1200,     bfd_mach_avr1},
  70   {"attiny10",  AVR_ISA_TINY1,    bfd_mach_avr1}, /* XXX -> tn11 */
  71   {"attiny11",  AVR_ISA_TINY1,    bfd_mach_avr1},
  72   {"attiny12",  AVR_ISA_TINY1,    bfd_mach_avr1},
  73   {"attiny15",  AVR_ISA_TINY1,    bfd_mach_avr1},
  74   {"attiny28",  AVR_ISA_TINY1,    bfd_mach_avr1},
  75   {"at90s2313", AVR_ISA_2xxx,     bfd_mach_avr2},
  76   {"at90s2323", AVR_ISA_2xxx,     bfd_mach_avr2},
  77   {"at90s2333", AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 4433 */
  78   {"at90s2343", AVR_ISA_2xxx,     bfd_mach_avr2},
  79   {"attiny22",  AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 2343 */
  80   {"attiny26",  AVR_ISA_2xxx,     bfd_mach_avr2},
  81   {"at90s4433", AVR_ISA_2xxx,     bfd_mach_avr2},
  82   {"at90s4414", AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 8515 */
  83   {"at90s4434", AVR_ISA_2xxx,     bfd_mach_avr2}, /* XXX -> 8535 */
  84   {"at90s8515", AVR_ISA_2xxx,     bfd_mach_avr2},
  85   {"at90s8535", AVR_ISA_2xxx,     bfd_mach_avr2},
  86   {"at90c8534", AVR_ISA_2xxx,     bfd_mach_avr2},
  87   {"at86rf401", AVR_ISA_2xxx,     bfd_mach_avr2},
  88   {"attiny13",  AVR_ISA_TINY2,    bfd_mach_avr2},
  89   {"attiny2313",AVR_ISA_TINY2,    bfd_mach_avr2},
  90   {"atmega603", AVR_ISA_M603,     bfd_mach_avr3}, /* XXX -> m103 */
  91   {"atmega103", AVR_ISA_M103,     bfd_mach_avr3},
  92   {"at43usb320",AVR_ISA_M103,     bfd_mach_avr3},
  93   {"at43usb355",AVR_ISA_M603,     bfd_mach_avr3},
  94   {"at76c711",  AVR_ISA_M603,     bfd_mach_avr3},
  95   {"atmega48",  AVR_ISA_M8,       bfd_mach_avr4},
  96   {"atmega8",   AVR_ISA_M8,       bfd_mach_avr4},
  97   {"atmega83",  AVR_ISA_M8,       bfd_mach_avr4}, /* XXX -> m8535 */
  98   {"atmega85",  AVR_ISA_M8,       bfd_mach_avr4}, /* XXX -> m8 */
  99   {"atmega88",  AVR_ISA_M8,       bfd_mach_avr4},
 100   {"atmega8515",AVR_ISA_M8,       bfd_mach_avr4},
 101   {"atmega8535",AVR_ISA_M8,       bfd_mach_avr4},
 102   {"atmega16",  AVR_ISA_M323,     bfd_mach_avr5},
 103   {"atmega161", AVR_ISA_M161,     bfd_mach_avr5},
 104   {"atmega162", AVR_ISA_M323,     bfd_mach_avr5},
 105   {"atmega163", AVR_ISA_M161,     bfd_mach_avr5},
 106   {"atmega165", AVR_ISA_M323,     bfd_mach_avr5},
 107   {"atmega168", AVR_ISA_M323,     bfd_mach_avr5},
 108   {"atmega169", AVR_ISA_M323,     bfd_mach_avr5},
 109   {"atmega32",  AVR_ISA_M323,     bfd_mach_avr5},
 110   {"atmega323", AVR_ISA_M323,     bfd_mach_avr5},
 111   {"atmega325", AVR_ISA_M323,     bfd_mach_avr5},
 112   {"atmega3250",AVR_ISA_M323,     bfd_mach_avr5},
 113   {"atmega64",  AVR_ISA_M323,     bfd_mach_avr5},
 114   {"atmega128", AVR_ISA_M128,     bfd_mach_avr5},
 115   {"atmega645", AVR_ISA_M323,     bfd_mach_avr5},
 116   {"atmega6450",AVR_ISA_M323,     bfd_mach_avr5},
 117   {"at90can128",AVR_ISA_M128,     bfd_mach_avr5},
 118   {"at94k",     AVR_ISA_94K,      bfd_mach_avr5},
 119   {NULL, 0, 0}
 120 };
 121
 122 /* Current MCU type.  */
 123 static struct mcu_type_s default_mcu = {"avr2", AVR_ISA_2xxx,bfd_mach_avr2};
 124 static struct mcu_type_s *avr_mcu = &default_mcu;
 125
 126 /* AVR target-specific switches.  */
 127 struct avr_opt_s
 128 {
 129   int all_opcodes;  /* -mall-opcodes: accept all known AVR opcodes  */
 130   int no_skip_bug;  /* -mno-skip-bug: no warnings for skipping 2-word insns  */
 131   int no_wrap;      /* -mno-wrap: reject rjmp/rcall with 8K wrap-around  */
 132 };
 133
 134 static struct avr_opt_s avr_opt = { 0, 0, 0 };
 135
 136 const char EXP_CHARS[] = "eE";
 137 const char FLT_CHARS[] = "dD";
 138 static void avr_set_arch (int dummy);
 139
 140 /* The target specific pseudo-ops which we support.  */
 141 const pseudo_typeS md_pseudo_table[] =
 142 {
 143   {"arch", avr_set_arch,        0},
 144   { NULL,       NULL,           0}
 145 };
 146
 147 #define LDI_IMMEDIATE(x) (((x) & 0xf) | (((x) << 4) & 0xf00))
 148
 149 static void show_mcu_list PARAMS ((FILE *));
 150 static char *skip_space PARAMS ((char *));
 151 static char *extract_word PARAMS ((char *, char *, int));
 152 static unsigned int avr_operand PARAMS ((struct avr_opcodes_s *,
 153                                          int, char *, char **));
 154 static unsigned int avr_operands PARAMS ((struct avr_opcodes_s *, char **));
 155 static unsigned int avr_get_constant PARAMS ((char *, int));
 156 static char *parse_exp PARAMS ((char *, expressionS *));
 157 static bfd_reloc_code_real_type avr_ldi_expression PARAMS ((expressionS *));
 158
 159 #define EXP_MOD_NAME(i) exp_mod[i].name
 160 #define EXP_MOD_RELOC(i) exp_mod[i].reloc
 161 #define EXP_MOD_NEG_RELOC(i) exp_mod[i].neg_reloc
 162 #define HAVE_PM_P(i) exp_mod[i].have_pm
 163
 164 struct exp_mod_s
 165 {
 166   char *name;
 167   bfd_reloc_code_real_type reloc;
 168   bfd_reloc_code_real_type neg_reloc;
 169   int have_pm;
 170 };
 171
 172 static struct exp_mod_s exp_mod[] =
 173 {
 174   {"hh8",    BFD_RELOC_AVR_HH8_LDI,    BFD_RELOC_AVR_HH8_LDI_NEG,    1},
 175   {"pm_hh8", BFD_RELOC_AVR_HH8_LDI_PM, BFD_RELOC_AVR_HH8_LDI_PM_NEG, 0},
 176   {"hi8",    BFD_RELOC_AVR_HI8_LDI,    BFD_RELOC_AVR_HI8_LDI_NEG,    1},
 177   {"pm_hi8", BFD_RELOC_AVR_HI8_LDI_PM, BFD_RELOC_AVR_HI8_LDI_PM_NEG, 0},
 178   {"lo8",    BFD_RELOC_AVR_LO8_LDI,    BFD_RELOC_AVR_LO8_LDI_NEG,    1},
 179   {"pm_lo8", BFD_RELOC_AVR_LO8_LDI_PM, BFD_RELOC_AVR_LO8_LDI_PM_NEG, 0},
 180   {"hlo8",   -BFD_RELOC_AVR_LO8_LDI,   -BFD_RELOC_AVR_LO8_LDI_NEG,   0},
 181   {"hhi8",   -BFD_RELOC_AVR_HI8_LDI,   -BFD_RELOC_AVR_HI8_LDI_NEG,   0},
 182 };
 183
 184 /* Opcode hash table.  */
 185 static struct hash_control *avr_hash;
 186
 187 /* Reloc modifiers hash control (hh8,hi8,lo8,pm_xx).  */
 188 static struct hash_control *avr_mod_hash;
 189
 190 #define OPTION_MMCU 'm'
 191 #define OPTION_ALL_OPCODES (OPTION_MD_BASE + 1)
 192 #define OPTION_NO_SKIP_BUG (OPTION_MD_BASE + 2)
 193 #define OPTION_NO_WRAP     (OPTION_MD_BASE + 3)
 194
 195 struct option md_longopts[] =
 196 {
 197   { "mmcu",   required_argument, NULL, OPTION_MMCU        },
 198   { "mall-opcodes", no_argument, NULL, OPTION_ALL_OPCODES },
 199   { "mno-skip-bug", no_argument, NULL, OPTION_NO_SKIP_BUG },
 200   { "mno-wrap",     no_argument, NULL, OPTION_NO_WRAP     },
 201   { NULL, no_argument, NULL, 0 }
 202 };
 203
 204 size_t md_longopts_size = sizeof (md_longopts);
 205
 206 /* Display nicely formatted list of known MCU names.  */
 207
 208 static void
 209 show_mcu_list (stream)
 210      FILE *stream;
 211 {
 212   int i, x;
 213
 214   fprintf (stream, _("Known MCU names:"));
 215   x = 1000;
 216
 217   for (i = 0; mcu_types[i].name; i++)
 218     {
 219       int len = strlen (mcu_types[i].name);
 220
 221       x += len + 1;
 222
 223       if (x < 75)
 224         fprintf (stream, " %s", mcu_types[i].name);
 225       else
 226         {
 227           fprintf (stream, "\n  %s", mcu_types[i].name);
 228           x = len + 2;
 229         }
 230     }
 231
 232   fprintf (stream, "\n");
 233 }
 234
 235 static inline char *
 236 skip_space (s)
 237      char *s;
 238 {
 239   while (*s == ' ' || *s == '\t')
 240     ++s;
 241   return s;
 242 }
 243
 244 /* Extract one word from FROM and copy it to TO.  */
 245
 246 static char *
 247 extract_word (char *from, char *to, int limit)
 248 {
 249   char *op_start;
 250   char *op_end;
 251   int size = 0;
 252
 253   /* Drop leading whitespace.  */
 254   from = skip_space (from);
 255   *to = 0;
 256
 257   /* Find the op code end.  */
 258   for (op_start = op_end = from; *op_end != 0 && is_part_of_name (*op_end);)
 259     {
 260       to[size++] = *op_end++;
 261       if (size + 1 >= limit)
 262         break;
 263     }
 264
 265   to[size] = 0;
 266   return op_end;
 267 }
 268
 269 int
 270 md_estimate_size_before_relax (fragp, seg)
 271      fragS *fragp ATTRIBUTE_UNUSED;
 272      asection *seg ATTRIBUTE_UNUSED;
 273 {
 274   abort ();
 275   return 0;
 276 }
 277
 278 void
 279 md_show_usage (stream)
 280      FILE *stream;
 281 {
 282   fprintf (stream,
 283       _("AVR options:\n"
 284         "  -mmcu=[avr-name] select microcontroller variant\n"
 285         "                   [avr-name] can be:\n"
 286         "                   avr1 - AT90S1200, ATtiny1x, ATtiny28\n"
 287         "                   avr2 - AT90S2xxx, AT90S4xxx, AT90S8xxx, ATtiny22\n"
 288         "                   avr3 - ATmega103, ATmega603\n"
 289         "                   avr4 - ATmega83, ATmega85\n"
 290         "                   avr5 - ATmega161, ATmega163, ATmega32, AT94K\n"
 291         "                   or immediate microcontroller name.\n"));
 292   fprintf (stream,
 293       _("  -mall-opcodes    accept all AVR opcodes, even if not supported by MCU\n"
 294         "  -mno-skip-bug    disable warnings for skipping two-word instructions\n"
 295         "                   (default for avr4, avr5)\n"
 296         "  -mno-wrap        reject rjmp/rcall instructions with 8K wrap-around\n"
 297         "                   (default for avr3, avr5)\n"));
 298   show_mcu_list (stream);
 299 }
 300
 301 static void
 302 avr_set_arch (dummy)
 303      int dummy ATTRIBUTE_UNUSED;
 304 {
 305   char *str;
 306
 307   str = (char *) alloca (20);
 308   input_line_pointer = extract_word (input_line_pointer, str, 20);
 309   md_parse_option (OPTION_MMCU, str);
 310   bfd_set_arch_mach (stdoutput, TARGET_ARCH, avr_mcu->mach);
 311 }
 312
 313 int
 314 md_parse_option (c, arg)
 315      int c;
 316      char *arg;
 317 {
 318   switch (c)
 319     {
 320     case OPTION_MMCU:
 321       {
 322         int i;
 323         char *s = alloca (strlen (arg) + 1);
 324
 325         {
 326           char *t = s;
 327           char *arg1 = arg;
 328
 329           do
 330             *t = TOLOWER (*arg1++);
 331           while (*t++);
 332         }
 333
 334         for (i = 0; mcu_types[i].name; ++i)
 335           if (strcmp (mcu_types[i].name, s) == 0)
 336             break;
 337
 338         if (!mcu_types[i].name)
 339           {
 340             show_mcu_list (stderr);
 341             as_fatal (_("unknown MCU: %s\n"), arg);
 342           }
 343
 344         /* It is OK to redefine mcu type within the same avr[1-5] bfd machine
 345            type - this for allows passing -mmcu=... via gcc ASM_SPEC as well
 346            as .arch ... in the asm output at the same time.  */
 347         if (avr_mcu == &default_mcu || avr_mcu->mach == mcu_types[i].mach)
 348           avr_mcu = &mcu_types[i];
 349         else
 350           as_fatal (_("redefinition of mcu type `%s' to `%s'"),
 351                     avr_mcu->name, mcu_types[i].name);
 352         return 1;
 353       }
 354     case OPTION_ALL_OPCODES:
 355       avr_opt.all_opcodes = 1;
 356       return 1;
 357     case OPTION_NO_SKIP_BUG:
 358       avr_opt.no_skip_bug = 1;
 359       return 1;
 360     case OPTION_NO_WRAP:
 361       avr_opt.no_wrap = 1;
 362       return 1;
 363     }
 364
 365   return 0;
 366 }
 367
 368 symbolS *
 369 md_undefined_symbol (name)
 370      char *name ATTRIBUTE_UNUSED;
 371 {
 372   return 0;
 373 }
 374
 375 /* Turn a string in input_line_pointer into a floating point constant
 376    of type TYPE, and store the appropriate bytes in *LITP.  The number
 377    of LITTLENUMS emitted is stored in *SIZEP.  An error message is
 378    returned, or NULL on OK.  */
 379
 380 char *
 381 md_atof (type, litP, sizeP)
 382      int type;
 383      char *litP;
 384      int *sizeP;
 385 {
 386   int prec;
 387   LITTLENUM_TYPE words[4];
 388   LITTLENUM_TYPE *wordP;
 389   char *t;
 390
 391   switch (type)
 392     {
 393     case 'f':
 394       prec = 2;
 395       break;
 396     case 'd':
 397       prec = 4;
 398       break;
 399     default:
 400       *sizeP = 0;
 401       return _("bad call to md_atof");
 402     }
 403
 404   t = atof_ieee (input_line_pointer, type, words);
 405   if (t)
 406     input_line_pointer = t;
 407
 408   *sizeP = prec * sizeof (LITTLENUM_TYPE);
 409
 410   /* This loop outputs the LITTLENUMs in REVERSE order.  */
 411   for (wordP = words + prec - 1; prec--;)
 412     {
 413       md_number_to_chars (litP, (valueT) (*wordP--), sizeof (LITTLENUM_TYPE));
 414       litP += sizeof (LITTLENUM_TYPE);
 415     }
 416
 417   return NULL;
 418 }
 419
 420 void
 421 md_convert_frag (abfd, sec, fragP)
 422      bfd *abfd ATTRIBUTE_UNUSED;
 423      asection *sec ATTRIBUTE_UNUSED;
 424      fragS *fragP ATTRIBUTE_UNUSED;
 425 {
 426   abort ();
 427 }
 428
 429 void
 430 md_begin ()
 431 {
 432   unsigned int i;
 433   struct avr_opcodes_s *opcode;
 434   avr_hash = hash_new ();
 435
 436   /* Insert unique names into hash table.  This hash table then provides a
 437      quick index to the first opcode with a particular name in the opcode
 438      table.  */
 439   for (opcode = avr_opcodes; opcode->name; opcode++)
 440     hash_insert (avr_hash, opcode->name, (char *) opcode);
 441
 442   avr_mod_hash = hash_new ();
 443
 444   for (i = 0; i < sizeof (exp_mod) / sizeof (exp_mod[0]); ++i)
 445     hash_insert (avr_mod_hash, EXP_MOD_NAME (i), (void *) (i + 10));
 446
 447   bfd_set_arch_mach (stdoutput, TARGET_ARCH, avr_mcu->mach);
 448 }
 449
 450 /* Resolve STR as a constant expression and return the result.
 451    If result greater than MAX then error.  */
 452
 453 static unsigned int
 454 avr_get_constant (str, max)
 455      char *str;
 456      int max;
 457 {
 458   expressionS ex;
 459   str = skip_space (str);
 460   input_line_pointer = str;
 461   expression (&ex);
 462
 463   if (ex.X_op != O_constant)
 464     as_bad (_("constant value required"));
 465
 466   if (ex.X_add_number > max || ex.X_add_number < 0)
 467     as_bad (_("number must be less than %d"), max + 1);
 468
 469   return ex.X_add_number;
 470 }
 471
 472 /* Parse instruction operands.
 473    Return binary opcode.  */
 474
 475 static unsigned int
 476 avr_operands (opcode, line)
 477      struct avr_opcodes_s *opcode;
 478      char **line;
 479 {
 480   char *op = opcode->constraints;
 481   unsigned int bin = opcode->bin_opcode;
 482   char *frag = frag_more (opcode->insn_size * 2);
 483   char *str = *line;
 484   int where = frag - frag_now->fr_literal;
 485   static unsigned int prev = 0;  /* Previous opcode.  */
 486
 487   /* Opcode have operands.  */
 488   if (*op)
 489     {
 490       unsigned int reg1 = 0;
 491       unsigned int reg2 = 0;
 492       int reg1_present = 0;
 493       int reg2_present = 0;
 494
 495       /* Parse first operand.  */
 496       if (REGISTER_P (*op))
 497         reg1_present = 1;
 498       reg1 = avr_operand (opcode, where, op, &str);
 499       ++op;
 500
 501       /* Parse second operand.  */
 502       if (*op)
 503         {
 504           if (*op == ',')
 505             ++op;
 506
 507           if (*op == '=')
 508             {
 509               reg2 = reg1;
 510               reg2_present = 1;
 511             }
 512           else
 513             {
 514               if (REGISTER_P (*op))
 515                 reg2_present = 1;
 516
 517               str = skip_space (str);
 518               if (*str++ != ',')
 519                 as_bad (_("`,' required"));
 520               str = skip_space (str);
 521
 522               reg2 = avr_operand (opcode, where, op, &str);
 523
 524             }
 525
 526           if (reg1_present && reg2_present)
 527             reg2 = (reg2 & 0xf) | ((reg2 << 5) & 0x200);
 528           else if (reg2_present)
 529             reg2 <<= 4;
 530         }
 531       if (reg1_present)
 532         reg1 <<= 4;
 533       bin |= reg1 | reg2;
 534     }
 535
 536   /* Detect undefined combinations (like ld r31,Z+).  */
 537   if (!avr_opt.all_opcodes && AVR_UNDEF_P (bin))
 538     as_warn (_("undefined combination of operands"));
 539
 540   if (opcode->insn_size == 2)
 541     {
 542       /* Warn if the previous opcode was cpse/sbic/sbis/sbrc/sbrs
 543          (AVR core bug, fixed in the newer devices).  */
 544
 545       if (!(avr_opt.no_skip_bug ||
 546             (avr_mcu->isa & (AVR_ISA_MUL | AVR_ISA_MOVW)))
 547           && AVR_SKIP_P (prev))
 548         as_warn (_("skipping two-word instruction"));
 549
 550       bfd_putl32 ((bfd_vma) bin, frag);
 551     }
 552   else
 553     bfd_putl16 ((bfd_vma) bin, frag);
 554
 555   prev = bin;
 556   *line = str;
 557   return bin;
 558 }
 559
 560 /* Parse for ldd/std offset */
 561
 562 static void
 563 avr_offset_expression (expressionS *exp)
 564 {
 565   char *str = input_line_pointer;
 566   char *tmp;
 567   char op[8];
 568
 569   tmp = str;
 570   str = extract_word (str, op, sizeof (op));
 571
 572   input_line_pointer = tmp;
 573   expression (exp);
 574
 575   /* Warn about expressions that fail to use lo8 ().  */
 576   if (exp->X_op == O_constant)
 577     {
 578       int x = exp->X_add_number;
 579
 580       if (x < -255 || x > 255)
 581         as_warn (_("constant out of 8-bit range: %d"), x);
 582     }
 583 }
 584
 585 /* Parse one instruction operand.
 586    Return operand bitmask.  Also fixups can be generated.  */
 587
 588 static unsigned int
 589 avr_operand (opcode, where, op, line)
 590      struct avr_opcodes_s *opcode;
 591      int where;
 592      char *op;
 593      char **line;
 594 {
 595   expressionS op_expr;
 596   unsigned int op_mask = 0;
 597   char *str = skip_space (*line);
 598
 599   switch (*op)
 600     {
 601       /* Any register operand.  */
 602     case 'w':
 603     case 'd':
 604     case 'r':
 605     case 'a':
 606     case 'v':
 607       if (*str == 'r' || *str == 'R')
 608         {
 609           char r_name[20];
 610
 611           str = extract_word (str, r_name, sizeof (r_name));
 612           op_mask = 0xff;
 613           if (ISDIGIT (r_name[1]))
 614             {
 615               if (r_name[2] == '\0')
 616                 op_mask = r_name[1] - '0';
 617               else if (r_name[1] != '0'
 618                        && ISDIGIT (r_name[2])
 619                        && r_name[3] == '\0')
 620                 op_mask = (r_name[1] - '0') * 10 + r_name[2] - '0';
 621             }
 622         }
 623       else
 624         {
 625           op_mask = avr_get_constant (str, 31);
 626           str = input_line_pointer;
 627         }
 628
 629       if (op_mask <= 31)
 630         {
 631           switch (*op)
 632             {
 633             case 'a':
 634               if (op_mask < 16 || op_mask > 23)
 635                 as_bad (_("register r16-r23 required"));
 636               op_mask -= 16;
 637               break;
 638
 639             case 'd':
 640               if (op_mask < 16)
 641                 as_bad (_("register number above 15 required"));
 642               op_mask -= 16;
 643               break;
 644
 645             case 'v':
 646               if (op_mask & 1)
 647                 as_bad (_("even register number required"));
 648               op_mask >>= 1;
 649               break;
 650
 651             case 'w':
 652               if ((op_mask & 1) || op_mask < 24)
 653                 as_bad (_("register r24, r26, r28 or r30 required"));
 654               op_mask = (op_mask - 24) >> 1;
 655               break;
 656             }
 657           break;
 658         }
 659       as_bad (_("register name or number from 0 to 31 required"));
 660       break;
 661
 662     case 'e':
 663       {
 664         char c;
 665
 666         if (*str == '-')
 667           {
 668             str = skip_space (str + 1);
 669             op_mask = 0x1002;
 670           }
 671         c = TOLOWER (*str);
 672         if (c == 'x')
 673           op_mask |= 0x100c;
 674         else if (c == 'y')
 675           op_mask |= 0x8;
 676         else if (c != 'z')
 677           as_bad (_("pointer register (X, Y or Z) required"));
 678
 679         str = skip_space (str + 1);
 680         if (*str == '+')
 681           {
 682             ++str;
 683             if (op_mask & 2)
 684               as_bad (_("cannot both predecrement and postincrement"));
 685             op_mask |= 0x1001;
 686           }
 687
 688         /* avr1 can do "ld r,Z" and "st Z,r" but no other pointer
 689            registers, no predecrement, no postincrement.  */
 690         if (!avr_opt.all_opcodes && (op_mask & 0x100F)
 691             && !(avr_mcu->isa & AVR_ISA_SRAM))
 692           as_bad (_("addressing mode not supported"));
 693       }
 694       break;
 695
 696     case 'z':
 697       if (*str == '-')
 698         as_bad (_("can't predecrement"));
 699
 700       if (! (*str == 'z' || *str == 'Z'))
 701         as_bad (_("pointer register Z required"));
 702
 703       str = skip_space (str + 1);
 704
 705       if (*str == '+')
 706         {
 707           ++str;
 708           op_mask |= 1;
 709         }
 710       break;
 711
 712     case 'b':
 713       {
 714         char c = TOLOWER (*str++);
 715
 716         if (c == 'y')
 717           op_mask |= 0x8;
 718         else if (c != 'z')
 719           as_bad (_("pointer register (Y or Z) required"));
 720         str = skip_space (str);
 721         if (*str++ == '+')
 722           {
 723             input_line_pointer = str;
 724             avr_offset_expression (& op_expr);
 725             str = input_line_pointer;
 726             fix_new_exp (frag_now, where, 3,
 727                          &op_expr, FALSE, BFD_RELOC_AVR_6);
 728           }
 729       }
 730       break;
 731
 732     case 'h':
 733       str = parse_exp (str, &op_expr);
 734       fix_new_exp (frag_now, where, opcode->insn_size * 2,
 735                    &op_expr, FALSE, BFD_RELOC_AVR_CALL);
 736       break;
 737
 738     case 'L':
 739       str = parse_exp (str, &op_expr);
 740       fix_new_exp (frag_now, where, opcode->insn_size * 2,
 741                    &op_expr, TRUE, BFD_RELOC_AVR_13_PCREL);
 742       break;
 743
 744     case 'l':
 745       str = parse_exp (str, &op_expr);
 746       fix_new_exp (frag_now, where, opcode->insn_size * 2,
 747                    &op_expr, TRUE, BFD_RELOC_AVR_7_PCREL);
 748       break;
 749
 750     case 'i':
 751       str = parse_exp (str, &op_expr);
 752       fix_new_exp (frag_now, where + 2, opcode->insn_size * 2,
 753                    &op_expr, FALSE, BFD_RELOC_16);
 754       break;
 755
 756     case 'M':
 757       {
 758         bfd_reloc_code_real_type r_type;
 759
 760         input_line_pointer = str;
 761         r_type = avr_ldi_expression (&op_expr);
 762         str = input_line_pointer;
 763         fix_new_exp (frag_now, where, 3,
 764                      &op_expr, FALSE, r_type);
 765       }
 766       break;
 767
 768     case 'n':
 769       {
 770         unsigned int x;
 771
 772         x = ~avr_get_constant (str, 255);
 773         str = input_line_pointer;
 774         op_mask |= (x & 0xf) | ((x << 4) & 0xf00);
 775       }
 776       break;
 777
 778     case 'K':
 779       input_line_pointer = str;
 780       avr_offset_expression (& op_expr);
 781       str = input_line_pointer;
 782       fix_new_exp (frag_now, where, 3,
 783                    & op_expr, FALSE, BFD_RELOC_AVR_6_ADIW);
 784       break;
 785
 786     case 'S':
 787     case 's':
 788       {
 789         unsigned int x;
 790
 791         x = avr_get_constant (str, 7);
 792         str = input_line_pointer;
 793         if (*op == 'S')
 794           x <<= 4;
 795         op_mask |= x;
 796       }
 797       break;
 798
 799     case 'P':
 800       {
 801         unsigned int x;
 802
 803         x = avr_get_constant (str, 63);
 804         str = input_line_pointer;
 805         op_mask |= (x & 0xf) | ((x & 0x30) << 5);
 806       }
 807       break;
 808
 809     case 'p':
 810       {
 811         unsigned int x;
 812
 813         x = avr_get_constant (str, 31);
 814         str = input_line_pointer;
 815         op_mask |= x << 3;
 816       }
 817       break;
 818
 819     case '?':
 820       break;
 821
 822     default:
 823       as_bad (_("unknown constraint `%c'"), *op);
 824     }
 825
 826   *line = str;
 827   return op_mask;
 828 }
 829
 830 /* GAS will call this function for each section at the end of the assembly,
 831    to permit the CPU backend to adjust the alignment of a section.  */
 832
 833 valueT
 834 md_section_align (seg, addr)
 835      asection *seg;
 836      valueT addr;
 837 {
 838   int align = bfd_get_section_alignment (stdoutput, seg);
 839   return ((addr + (1 << align) - 1) & (-1 << align));
 840 }
 841
 842 /* If you define this macro, it should return the offset between the
 843    address of a PC relative fixup and the position from which the PC
 844    relative adjustment should be made.  On many processors, the base
 845    of a PC relative instruction is the next instruction, so this
 846    macro would return the length of an instruction.  */
 847
 848 long
 849 md_pcrel_from_section (fixp, sec)
 850      fixS *fixp;
 851      segT sec;
 852 {
 853   if (fixp->fx_addsy != (symbolS *) NULL
 854       && (!S_IS_DEFINED (fixp->fx_addsy)
 855           || (S_GET_SEGMENT (fixp->fx_addsy) != sec)))
 856     return 0;
 857
 858   return fixp->fx_frag->fr_address + fixp->fx_where;
 859 }
 860
 861 /* GAS will call this for each fixup.  It should store the correct
 862    value in the object file.  */
 863
 864 void
 865 md_apply_fix3 (fixP, valP, seg)
 866      fixS *fixP;
 867      valueT * valP;
 868      segT seg;
 869 {
 870   unsigned char *where;
 871   unsigned long insn;
 872   long value = *valP;
 873
 874   if (fixP->fx_addsy == (symbolS *) NULL)
 875     fixP->fx_done = 1;
 876
 877   else if (fixP->fx_pcrel)
 878     {
 879       segT s = S_GET_SEGMENT (fixP->fx_addsy);
 880
 881       if (s == seg || s == absolute_section)
 882         {
 883           value += S_GET_VALUE (fixP->fx_addsy);
 884           fixP->fx_done = 1;
 885         }
 886     }
 887
 888   /* We don't actually support subtracting a symbol.  */
 889   if (fixP->fx_subsy != (symbolS *) NULL)
 890     as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex"));
 891
 892   switch (fixP->fx_r_type)
 893     {
 894     default:
 895       fixP->fx_no_overflow = 1;
 896       break;
 897     case BFD_RELOC_AVR_7_PCREL:
 898     case BFD_RELOC_AVR_13_PCREL:
 899     case BFD_RELOC_32:
 900     case BFD_RELOC_16:
 901     case BFD_RELOC_AVR_CALL:
 902       break;
 903     }
 904
 905   if (fixP->fx_done)
 906     {
 907       /* Fetch the instruction, insert the fully resolved operand
 908          value, and stuff the instruction back again.  */
 909       where = fixP->fx_frag->fr_literal + fixP->fx_where;
 910       insn = bfd_getl16 (where);
 911
 912       switch (fixP->fx_r_type)
 913         {
 914         case BFD_RELOC_AVR_7_PCREL:
 915           if (value & 1)
 916             as_bad_where (fixP->fx_file, fixP->fx_line,
 917                           _("odd address operand: %ld"), value);
 918
 919           /* Instruction addresses are always right-shifted by 1.  */
 920           value >>= 1;
 921           --value;                      /* Correct PC.  */
 922
 923           if (value < -64 || value > 63)
 924             as_bad_where (fixP->fx_file, fixP->fx_line,
 925                           _("operand out of range: %ld"), value);
 926           value = (value << 3) & 0x3f8;
 927           bfd_putl16 ((bfd_vma) (value | insn), where);
 928           break;
 929
 930         case BFD_RELOC_AVR_13_PCREL:
 931           if (value & 1)
 932             as_bad_where (fixP->fx_file, fixP->fx_line,
 933                           _("odd address operand: %ld"), value);
 934
 935           /* Instruction addresses are always right-shifted by 1.  */
 936           value >>= 1;
 937           --value;                      /* Correct PC.  */
 938
 939           if (value < -2048 || value > 2047)
 940             {
 941               /* No wrap for devices with >8K of program memory.  */
 942               if ((avr_mcu->isa & AVR_ISA_MEGA) || avr_opt.no_wrap)
 943                 as_bad_where (fixP->fx_file, fixP->fx_line,
 944                               _("operand out of range: %ld"), value);
 945             }
 946
 947           value &= 0xfff;
 948           bfd_putl16 ((bfd_vma) (value | insn), where);
 949           break;
 950
 951         case BFD_RELOC_32:
 952           bfd_putl16 ((bfd_vma) value, where);
 953           break;
 954
 955         case BFD_RELOC_16:
 956           bfd_putl16 ((bfd_vma) value, where);
 957           break;
 958
 959         case BFD_RELOC_AVR_16_PM:
 960           bfd_putl16 ((bfd_vma) (value >> 1), where);
 961           break;
 962
 963         case BFD_RELOC_AVR_LDI:
 964           if (value > 255)
 965             as_bad_where (fixP->fx_file, fixP->fx_line,
 966                           _("operand out of range: %ld"), value);
 967           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value), where);
 968           break;
 969
 970         case BFD_RELOC_AVR_6:
 971           if ((value > 63) || (value < 0))
 972             as_bad_where (fixP->fx_file, fixP->fx_line,
 973                           _("operand out of range: %ld"), value);
 974           bfd_putl16 ((bfd_vma) insn | ((value & 7) | ((value & (3 << 3)) << 7) | ((value & (1 << 5)) << 8)), where);
 975           break;
 976
 977         case BFD_RELOC_AVR_6_ADIW:
 978           if ((value > 63) || (value < 0))
 979             as_bad_where (fixP->fx_file, fixP->fx_line,
 980                           _("operand out of range: %ld"), value);
 981           bfd_putl16 ((bfd_vma) insn | (value & 0xf) | ((value & 0x30) << 2), where);
 982           break;
 983
 984         case BFD_RELOC_AVR_LO8_LDI:
 985           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value), where);
 986           break;
 987
 988         case -BFD_RELOC_AVR_LO8_LDI:
 989           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 16), where);
 990           break;
 991
 992         case BFD_RELOC_AVR_HI8_LDI:
 993           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 8), where);
 994           break;
 995
 996         case -BFD_RELOC_AVR_HI8_LDI:
 997           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 24), where);
 998           break;
 999
1000         case BFD_RELOC_AVR_HH8_LDI:
1001           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 16), where);
1002           break;
1003
1004         case BFD_RELOC_AVR_LO8_LDI_NEG:
1005           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value), where);
1006           break;
1007
1008         case -BFD_RELOC_AVR_LO8_LDI_NEG:
1009           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 16), where);
1010           break;
1011
1012         case BFD_RELOC_AVR_HI8_LDI_NEG:
1013           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 8), where);
1014           break;
1015
1016         case -BFD_RELOC_AVR_HI8_LDI_NEG:
1017           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 24), where);
1018           break;
1019
1020         case BFD_RELOC_AVR_HH8_LDI_NEG:
1021           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 16), where);
1022           break;
1023
1024         case BFD_RELOC_AVR_LO8_LDI_PM:
1025           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 1), where);
1026           break;
1027
1028         case BFD_RELOC_AVR_HI8_LDI_PM:
1029           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 9), where);
1030           break;
1031
1032         case BFD_RELOC_AVR_HH8_LDI_PM:
1033           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 17), where);
1034           break;
1035
1036         case BFD_RELOC_AVR_LO8_LDI_PM_NEG:
1037           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 1), where);
1038           break;
1039
1040         case BFD_RELOC_AVR_HI8_LDI_PM_NEG:
1041           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 9), where);
1042           break;
1043
1044         case BFD_RELOC_AVR_HH8_LDI_PM_NEG:
1045           bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 17), where);
1046           break;
1047
1048         case BFD_RELOC_AVR_CALL:
1049           {
1050             unsigned long x;
1051
1052             x = bfd_getl16 (where);
1053             if (value & 1)
1054               as_bad_where (fixP->fx_file, fixP->fx_line,
1055                             _("odd address operand: %ld"), value);
1056             value >>= 1;
1057             x |= ((value & 0x10000) | ((value << 3) & 0x1f00000)) >> 16;
1058             bfd_putl16 ((bfd_vma) x, where);
1059             bfd_putl16 ((bfd_vma) (value & 0xffff), where + 2);
1060           }
1061           break;
1062
1063         default:
1064           as_fatal (_("line %d: unknown relocation type: 0x%x"),
1065                     fixP->fx_line, fixP->fx_r_type);
1066           break;
1067         }
1068     }
1069   else
1070     {
1071       switch (fixP->fx_r_type)
1072         {
1073         case -BFD_RELOC_AVR_HI8_LDI_NEG:
1074         case -BFD_RELOC_AVR_HI8_LDI:
1075         case -BFD_RELOC_AVR_LO8_LDI_NEG:
1076         case -BFD_RELOC_AVR_LO8_LDI:
1077           as_bad_where (fixP->fx_file, fixP->fx_line,
1078                         _("only constant expression allowed"));
1079           fixP->fx_done = 1;
1080           break;
1081         default:
1082           break;
1083         }
1084     }
1085 }
1086
1087 /* A `BFD_ASSEMBLER' GAS will call this to generate a reloc.  GAS
1088    will pass the resulting reloc to `bfd_install_relocation'.  This
1089    currently works poorly, as `bfd_install_relocation' often does the
1090    wrong thing, and instances of `tc_gen_reloc' have been written to
1091    work around the problems, which in turns makes it difficult to fix
1092    `bfd_install_relocation'.  */
1093
1094 /* If while processing a fixup, a reloc really needs to be created
1095    then it is done here.  */
1096
1097 arelent *
1098 tc_gen_reloc (seg, fixp)
1099      asection *seg ATTRIBUTE_UNUSED;
1100      fixS *fixp;
1101 {
1102   arelent *reloc;
1103
1104   reloc = (arelent *) xmalloc (sizeof (arelent));
1105
1106   reloc->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
1107   *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
1108
1109   reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
1110   reloc->howto = bfd_reloc_type_lookup (stdoutput, fixp->fx_r_type);
1111   if (reloc->howto == (reloc_howto_type *) NULL)
1112     {
1113       as_bad_where (fixp->fx_file, fixp->fx_line,
1114                     _("reloc %d not supported by object file format"),
1115                     (int) fixp->fx_r_type);
1116       return NULL;
1117     }
1118
1119   if (fixp->fx_r_type == BFD_RELOC_VTABLE_INHERIT
1120       || fixp->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
1121     reloc->address = fixp->fx_offset;
1122
1123   reloc->addend = fixp->fx_offset;
1124
1125   return reloc;
1126 }
1127
1128 void
1129 md_assemble (str)
1130      char *str;
1131 {
1132   struct avr_opcodes_s *opcode;
1133   char op[11];
1134
1135   str = skip_space (extract_word (str, op, sizeof (op)));
1136
1137   if (!op[0])
1138     as_bad (_("can't find opcode "));
1139
1140   opcode = (struct avr_opcodes_s *) hash_find (avr_hash, op);
1141
1142   if (opcode == NULL)
1143     {
1144       as_bad (_("unknown opcode `%s'"), op);
1145       return;
1146     }
1147
1148   /* Special case for opcodes with optional operands (lpm, elpm) -
1149      version with operands exists in avr_opcodes[] in the next entry.  */
1150
1151   if (*str && *opcode->constraints == '?')
1152     ++opcode;
1153
1154   if (!avr_opt.all_opcodes && (opcode->isa & avr_mcu->isa) != opcode->isa)
1155     as_bad (_("illegal opcode %s for mcu %s"), opcode->name, avr_mcu->name);
1156
1157   /* We used to set input_line_pointer to the result of get_operands,
1158      but that is wrong.  Our caller assumes we don't change it.  */
1159   {
1160     char *t = input_line_pointer;
1161     avr_operands (opcode, &str);
1162     if (*skip_space (str))
1163       as_bad (_("garbage at end of line"));
1164     input_line_pointer = t;
1165   }
1166 }
1167
1168 /* Parse ordinary expression.  */
1169
1170 static char *
1171 parse_exp (s, op)
1172      char *s;
1173      expressionS *op;
1174 {
1175   input_line_pointer = s;
1176   expression (op);
1177   if (op->X_op == O_absent)
1178     as_bad (_("missing operand"));
1179   return input_line_pointer;
1180 }
1181
1182 /* Parse special expressions (needed for LDI command):
1183    xx8 (address)
1184    xx8 (-address)
1185    pm_xx8 (address)
1186    pm_xx8 (-address)
1187    where xx is: hh, hi, lo.  */
1188
1189 static bfd_reloc_code_real_type
1190 avr_ldi_expression (exp)
1191      expressionS *exp;
1192 {
1193   char *str = input_line_pointer;
1194   char *tmp;
1195   char op[8];
1196   int mod;
1197   tmp = str;
1198
1199   str = extract_word (str, op, sizeof (op));
1200
1201   if (op[0])
1202     {
1203       mod = (int) hash_find (avr_mod_hash, op);
1204
1205       if (mod)
1206         {
1207           int closes = 0;
1208
1209           mod -= 10;
1210           str = skip_space (str);
1211
1212           if (*str == '(')
1213             {
1214               int neg_p = 0;
1215
1216               ++str;
1217
1218               if (strncmp ("pm(", str, 3) == 0
1219                   || strncmp ("-(pm(", str, 5) == 0)
1220                 {
1221                   if (HAVE_PM_P (mod))
1222                     {
1223                       ++mod;
1224                       ++closes;
1225                     }
1226                   else
1227                     as_bad (_("illegal expression"));
1228
1229                   if (*str == '-')
1230                     {
1231                       neg_p = 1;
1232                       ++closes;
1233                       str += 5;
1234                     }
1235                   else
1236                     str += 3;
1237                 }
1238
1239               if (*str == '-' && *(str + 1) == '(')
1240                 {
1241                   neg_p ^= 1;
1242                   ++closes;
1243                   str += 2;
1244                 }
1245
1246               input_line_pointer = str;
1247               expression (exp);
1248
1249               do
1250                 {
1251                   if (*input_line_pointer != ')')
1252                     {
1253                       as_bad (_("`)' required"));
1254                       break;
1255                     }
1256                   input_line_pointer++;
1257                 }
1258               while (closes--);
1259
1260               return neg_p ? EXP_MOD_NEG_RELOC (mod) : EXP_MOD_RELOC (mod);
1261             }
1262         }
1263     }
1264
1265   input_line_pointer = tmp;
1266   expression (exp);
1267
1268   /* Warn about expressions that fail to use lo8 ().  */
1269   if (exp->X_op == O_constant)
1270     {
1271       int x = exp->X_add_number;
1272       if (x < -255 || x > 255)
1273         as_warn (_("constant out of 8-bit range: %d"), x);
1274     }
1275
1276   return BFD_RELOC_AVR_LDI;
1277 }
1278
1279 /* Flag to pass `pm' mode between `avr_parse_cons_expression' and
1280    `avr_cons_fix_new'.  */
1281 static int exp_mod_pm = 0;
1282
1283 /* Parse special CONS expression: pm (expression)
1284    which is used for addressing to a program memory.
1285    Relocation: BFD_RELOC_AVR_16_PM.  */
1286
1287 void
1288 avr_parse_cons_expression (exp, nbytes)
1289      expressionS *exp;
1290      int nbytes;
1291 {
1292   char *tmp;
1293
1294   exp_mod_pm = 0;
1295
1296   tmp = input_line_pointer = skip_space (input_line_pointer);
1297
1298   if (nbytes == 2)
1299     {
1300       char *pm_name = "pm";
1301       int len = strlen (pm_name);
1302
1303       if (strncasecmp (input_line_pointer, pm_name, len) == 0)
1304         {
1305           input_line_pointer = skip_space (input_line_pointer + len);
1306
1307           if (*input_line_pointer == '(')
1308             {
1309               input_line_pointer = skip_space (input_line_pointer + 1);
1310               exp_mod_pm = 1;
1311               expression (exp);
1312
1313               if (*input_line_pointer == ')')
1314                 ++input_line_pointer;
1315               else
1316                 {
1317                   as_bad (_("`)' required"));
1318                   exp_mod_pm = 0;
1319                 }
1320
1321               return;
1322             }
1323
1324           input_line_pointer = tmp;
1325         }
1326     }
1327
1328   expression (exp);
1329 }
1330
1331 void
1332 avr_cons_fix_new (frag, where, nbytes, exp)
1333      fragS *frag;
1334      int where;
1335      int nbytes;
1336      expressionS *exp;
1337 {
1338   if (exp_mod_pm == 0)
1339     {
1340       if (nbytes == 2)
1341         fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_16);
1342       else if (nbytes == 4)
1343         fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_32);
1344       else
1345         as_bad (_("illegal %srelocation size: %d"), "", nbytes);
1346     }
1347   else
1348     {
1349       if (nbytes == 2)
1350         fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_AVR_16_PM);
1351       else
1352         as_bad (_("illegal %srelocation size: %d"), "`pm' ", nbytes);
1353       exp_mod_pm = 0;
1354     }
1355 }