xref: /openbsd/gnu/usr.bin/binutils/gas/config/tc-avr.c (revision 274d7c50)
1 /* tc-avr.c -- Assembler code for the ATMEL AVR
2 
3    Copyright 1999, 2000, 2001, 2002 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_2xxx,     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   {"atmega603", AVR_ISA_M603,     bfd_mach_avr3}, /* XXX -> m103 */
89   {"atmega103", AVR_ISA_M103,     bfd_mach_avr3},
90   {"at43usb320",AVR_ISA_M103,     bfd_mach_avr3},
91   {"at43usb355",AVR_ISA_M603,     bfd_mach_avr3},
92   {"at76c711",  AVR_ISA_M603,     bfd_mach_avr3},
93   {"atmega8",   AVR_ISA_M8,       bfd_mach_avr4},
94   {"atmega83",  AVR_ISA_M8,       bfd_mach_avr4}, /* XXX -> m8535 */
95   {"atmega85",  AVR_ISA_M8,       bfd_mach_avr4}, /* XXX -> m8 */
96   {"atmega8515",AVR_ISA_M8,       bfd_mach_avr4},
97   {"atmega8535",AVR_ISA_M8,       bfd_mach_avr4},
98   {"atmega16",  AVR_ISA_M323,     bfd_mach_avr5},
99   {"atmega161", AVR_ISA_M161,     bfd_mach_avr5},
100   {"atmega162", AVR_ISA_M323,     bfd_mach_avr5},
101   {"atmega163", AVR_ISA_M161,     bfd_mach_avr5},
102   {"atmega169", AVR_ISA_M323,     bfd_mach_avr5},
103   {"atmega32",  AVR_ISA_M323,     bfd_mach_avr5},
104   {"atmega323", AVR_ISA_M323,     bfd_mach_avr5},
105   {"atmega64",  AVR_ISA_M323,     bfd_mach_avr5},
106   {"atmega128", AVR_ISA_M128,     bfd_mach_avr5},
107   {"at94k",     AVR_ISA_94K,      bfd_mach_avr5},
108   {NULL, 0, 0}
109 };
110 
111 /* Current MCU type.  */
112 static struct mcu_type_s default_mcu = {"avr2", AVR_ISA_2xxx,bfd_mach_avr2};
113 static struct mcu_type_s *avr_mcu = &default_mcu;
114 
115 /* AVR target-specific switches.  */
116 struct avr_opt_s
117 {
118   int all_opcodes;  /* -mall-opcodes: accept all known AVR opcodes  */
119   int no_skip_bug;  /* -mno-skip-bug: no warnings for skipping 2-word insns  */
120   int no_wrap;      /* -mno-wrap: reject rjmp/rcall with 8K wrap-around  */
121 };
122 
123 static struct avr_opt_s avr_opt = { 0, 0, 0 };
124 
125 const char EXP_CHARS[] = "eE";
126 const char FLT_CHARS[] = "dD";
127 static void avr_set_arch (int dummy);
128 
129 /* The target specific pseudo-ops which we support.  */
130 const pseudo_typeS md_pseudo_table[] =
131 {
132   {"arch", avr_set_arch,	0},
133   { NULL,	NULL,		0}
134 };
135 
136 #define LDI_IMMEDIATE(x) (((x) & 0xf) | (((x) << 4) & 0xf00))
137 
138 static void show_mcu_list PARAMS ((FILE *));
139 static char *skip_space PARAMS ((char *));
140 static char *extract_word PARAMS ((char *, char *, int));
141 static unsigned int avr_operand PARAMS ((struct avr_opcodes_s *,
142 					 int, char *, char **));
143 static unsigned int avr_operands PARAMS ((struct avr_opcodes_s *, char **));
144 static unsigned int avr_get_constant PARAMS ((char *, int));
145 static char *parse_exp PARAMS ((char *, expressionS *));
146 static bfd_reloc_code_real_type avr_ldi_expression PARAMS ((expressionS *));
147 
148 #define EXP_MOD_NAME(i) exp_mod[i].name
149 #define EXP_MOD_RELOC(i) exp_mod[i].reloc
150 #define EXP_MOD_NEG_RELOC(i) exp_mod[i].neg_reloc
151 #define HAVE_PM_P(i) exp_mod[i].have_pm
152 
153 struct exp_mod_s
154 {
155   char *name;
156   bfd_reloc_code_real_type reloc;
157   bfd_reloc_code_real_type neg_reloc;
158   int have_pm;
159 };
160 
161 static struct exp_mod_s exp_mod[] =
162 {
163   {"hh8",    BFD_RELOC_AVR_HH8_LDI,    BFD_RELOC_AVR_HH8_LDI_NEG,    1},
164   {"pm_hh8", BFD_RELOC_AVR_HH8_LDI_PM, BFD_RELOC_AVR_HH8_LDI_PM_NEG, 0},
165   {"hi8",    BFD_RELOC_AVR_HI8_LDI,    BFD_RELOC_AVR_HI8_LDI_NEG,    1},
166   {"pm_hi8", BFD_RELOC_AVR_HI8_LDI_PM, BFD_RELOC_AVR_HI8_LDI_PM_NEG, 0},
167   {"lo8",    BFD_RELOC_AVR_LO8_LDI,    BFD_RELOC_AVR_LO8_LDI_NEG,    1},
168   {"pm_lo8", BFD_RELOC_AVR_LO8_LDI_PM, BFD_RELOC_AVR_LO8_LDI_PM_NEG, 0},
169   {"hlo8",   -BFD_RELOC_AVR_LO8_LDI,   -BFD_RELOC_AVR_LO8_LDI_NEG,   0},
170   {"hhi8",   -BFD_RELOC_AVR_HI8_LDI,   -BFD_RELOC_AVR_HI8_LDI_NEG,   0},
171 };
172 
173 /* Opcode hash table.  */
174 static struct hash_control *avr_hash;
175 
176 /* Reloc modifiers hash control (hh8,hi8,lo8,pm_xx).  */
177 static struct hash_control *avr_mod_hash;
178 
179 #define OPTION_MMCU 'm'
180 #define OPTION_ALL_OPCODES (OPTION_MD_BASE + 1)
181 #define OPTION_NO_SKIP_BUG (OPTION_MD_BASE + 2)
182 #define OPTION_NO_WRAP     (OPTION_MD_BASE + 3)
183 
184 struct option md_longopts[] =
185 {
186   { "mmcu",   required_argument, NULL, OPTION_MMCU        },
187   { "mall-opcodes", no_argument, NULL, OPTION_ALL_OPCODES },
188   { "mno-skip-bug", no_argument, NULL, OPTION_NO_SKIP_BUG },
189   { "mno-wrap",     no_argument, NULL, OPTION_NO_WRAP     },
190   { NULL, no_argument, NULL, 0 }
191 };
192 
193 size_t md_longopts_size = sizeof (md_longopts);
194 
195 /* Display nicely formatted list of known MCU names.  */
196 
197 static void
198 show_mcu_list (stream)
199      FILE *stream;
200 {
201   int i, x;
202 
203   fprintf (stream, _("Known MCU names:"));
204   x = 1000;
205 
206   for (i = 0; mcu_types[i].name; i++)
207     {
208       int len = strlen (mcu_types[i].name);
209 
210       x += len + 1;
211 
212       if (x < 75)
213 	fprintf (stream, " %s", mcu_types[i].name);
214       else
215 	{
216 	  fprintf (stream, "\n  %s", mcu_types[i].name);
217 	  x = len + 2;
218 	}
219     }
220 
221   fprintf (stream, "\n");
222 }
223 
224 static inline char *
225 skip_space (s)
226      char *s;
227 {
228   while (*s == ' ' || *s == '\t')
229     ++s;
230   return s;
231 }
232 
233 /* Extract one word from FROM and copy it to TO.  */
234 
235 static char *
236 extract_word (char *from, char *to, int limit)
237 {
238   char *op_start;
239   char *op_end;
240   int size = 0;
241 
242   /* Drop leading whitespace.  */
243   from = skip_space (from);
244   *to = 0;
245 
246   /* Find the op code end.  */
247   for (op_start = op_end = from; *op_end != 0 && is_part_of_name (*op_end);)
248     {
249       to[size++] = *op_end++;
250       if (size + 1 >= limit)
251 	break;
252     }
253 
254   to[size] = 0;
255   return op_end;
256 }
257 
258 int
259 md_estimate_size_before_relax (fragp, seg)
260      fragS *fragp ATTRIBUTE_UNUSED;
261      asection *seg ATTRIBUTE_UNUSED;
262 {
263   abort ();
264   return 0;
265 }
266 
267 void
268 md_show_usage (stream)
269      FILE *stream;
270 {
271   fprintf (stream,
272       _("AVR options:\n"
273 	"  -mmcu=[avr-name] select microcontroller variant\n"
274 	"                   [avr-name] can be:\n"
275 	"                   avr1 - AT90S1200, ATtiny1x, ATtiny28\n"
276 	"                   avr2 - AT90S2xxx, AT90S4xxx, AT90S8xxx, ATtiny22\n"
277 	"                   avr3 - ATmega103, ATmega603\n"
278 	"                   avr4 - ATmega83, ATmega85\n"
279 	"                   avr5 - ATmega161, ATmega163, ATmega32, AT94K\n"
280 	"                   or immediate microcontroller name.\n"));
281   fprintf (stream,
282       _("  -mall-opcodes    accept all AVR opcodes, even if not supported by MCU\n"
283 	"  -mno-skip-bug    disable warnings for skipping two-word instructions\n"
284 	"                   (default for avr4, avr5)\n"
285 	"  -mno-wrap        reject rjmp/rcall instructions with 8K wrap-around\n"
286 	"                   (default for avr3, avr5)\n"));
287   show_mcu_list (stream);
288 }
289 
290 static void
291 avr_set_arch (dummy)
292      int dummy ATTRIBUTE_UNUSED;
293 {
294   char *str;
295 
296   str = (char *) alloca (20);
297   input_line_pointer = extract_word (input_line_pointer, str, 20);
298   md_parse_option (OPTION_MMCU, str);
299   bfd_set_arch_mach (stdoutput, TARGET_ARCH, avr_mcu->mach);
300 }
301 
302 int
303 md_parse_option (c, arg)
304      int c;
305      char *arg;
306 {
307   switch (c)
308     {
309     case OPTION_MMCU:
310       {
311 	int i;
312 	char *s = alloca (strlen (arg) + 1);
313 
314 	{
315 	  char *t = s;
316 	  char *arg1 = arg;
317 
318 	  do
319 	    *t = TOLOWER (*arg1++);
320 	  while (*t++);
321 	}
322 
323 	for (i = 0; mcu_types[i].name; ++i)
324 	  if (strcmp (mcu_types[i].name, s) == 0)
325 	    break;
326 
327 	if (!mcu_types[i].name)
328 	  {
329 	    show_mcu_list (stderr);
330 	    as_fatal (_("unknown MCU: %s\n"), arg);
331 	  }
332 
333 	/* It is OK to redefine mcu type within the same avr[1-5] bfd machine
334 	   type - this for allows passing -mmcu=... via gcc ASM_SPEC as well
335 	   as .arch ... in the asm output at the same time.  */
336 	if (avr_mcu == &default_mcu || avr_mcu->mach == mcu_types[i].mach)
337 	  avr_mcu = &mcu_types[i];
338 	else
339 	  as_fatal (_("redefinition of mcu type `%s' to `%s'"),
340 		    avr_mcu->name, mcu_types[i].name);
341 	return 1;
342       }
343     case OPTION_ALL_OPCODES:
344       avr_opt.all_opcodes = 1;
345       return 1;
346     case OPTION_NO_SKIP_BUG:
347       avr_opt.no_skip_bug = 1;
348       return 1;
349     case OPTION_NO_WRAP:
350       avr_opt.no_wrap = 1;
351       return 1;
352     }
353 
354   return 0;
355 }
356 
357 symbolS *
358 md_undefined_symbol (name)
359      char *name ATTRIBUTE_UNUSED;
360 {
361   return 0;
362 }
363 
364 /* Turn a string in input_line_pointer into a floating point constant
365    of type TYPE, and store the appropriate bytes in *LITP.  The number
366    of LITTLENUMS emitted is stored in *SIZEP.  An error message is
367    returned, or NULL on OK.  */
368 
369 char *
370 md_atof (type, litP, sizeP)
371      int type;
372      char *litP;
373      int *sizeP;
374 {
375   int prec;
376   LITTLENUM_TYPE words[4];
377   LITTLENUM_TYPE *wordP;
378   char *t;
379 
380   switch (type)
381     {
382     case 'f':
383       prec = 2;
384       break;
385     case 'd':
386       prec = 4;
387       break;
388     default:
389       *sizeP = 0;
390       return _("bad call to md_atof");
391     }
392 
393   t = atof_ieee (input_line_pointer, type, words);
394   if (t)
395     input_line_pointer = t;
396 
397   *sizeP = prec * sizeof (LITTLENUM_TYPE);
398 
399   /* This loop outputs the LITTLENUMs in REVERSE order.  */
400   for (wordP = words + prec - 1; prec--;)
401     {
402       md_number_to_chars (litP, (valueT) (*wordP--), sizeof (LITTLENUM_TYPE));
403       litP += sizeof (LITTLENUM_TYPE);
404     }
405 
406   return NULL;
407 }
408 
409 void
410 md_convert_frag (abfd, sec, fragP)
411      bfd *abfd ATTRIBUTE_UNUSED;
412      asection *sec ATTRIBUTE_UNUSED;
413      fragS *fragP ATTRIBUTE_UNUSED;
414 {
415   abort ();
416 }
417 
418 void
419 md_begin ()
420 {
421   unsigned int i;
422   struct avr_opcodes_s *opcode;
423   avr_hash = hash_new ();
424 
425   /* Insert unique names into hash table.  This hash table then provides a
426      quick index to the first opcode with a particular name in the opcode
427      table.  */
428   for (opcode = avr_opcodes; opcode->name; opcode++)
429     hash_insert (avr_hash, opcode->name, (char *) opcode);
430 
431   avr_mod_hash = hash_new ();
432 
433   for (i = 0; i < sizeof (exp_mod) / sizeof (exp_mod[0]); ++i)
434     hash_insert (avr_mod_hash, EXP_MOD_NAME (i), (void *) (i + 10));
435 
436   bfd_set_arch_mach (stdoutput, TARGET_ARCH, avr_mcu->mach);
437 }
438 
439 /* Resolve STR as a constant expression and return the result.
440    If result greater than MAX then error.  */
441 
442 static unsigned int
443 avr_get_constant (str, max)
444      char *str;
445      int max;
446 {
447   expressionS ex;
448   str = skip_space (str);
449   input_line_pointer = str;
450   expression (&ex);
451 
452   if (ex.X_op != O_constant)
453     as_bad (_("constant value required"));
454 
455   if (ex.X_add_number > max || ex.X_add_number < 0)
456     as_bad (_("number must be less than %d"), max + 1);
457 
458   return ex.X_add_number;
459 }
460 
461 /* Parse instruction operands.
462    Return binary opcode.  */
463 
464 static unsigned int
465 avr_operands (opcode, line)
466      struct avr_opcodes_s *opcode;
467      char **line;
468 {
469   char *op = opcode->constraints;
470   unsigned int bin = opcode->bin_opcode;
471   char *frag = frag_more (opcode->insn_size * 2);
472   char *str = *line;
473   int where = frag - frag_now->fr_literal;
474   static unsigned int prev = 0;  /* Previous opcode.  */
475 
476   /* Opcode have operands.  */
477   if (*op)
478     {
479       unsigned int reg1 = 0;
480       unsigned int reg2 = 0;
481       int reg1_present = 0;
482       int reg2_present = 0;
483 
484       /* Parse first operand.  */
485       if (REGISTER_P (*op))
486 	reg1_present = 1;
487       reg1 = avr_operand (opcode, where, op, &str);
488       ++op;
489 
490       /* Parse second operand.  */
491       if (*op)
492 	{
493 	  if (*op == ',')
494 	    ++op;
495 
496 	  if (*op == '=')
497 	    {
498 	      reg2 = reg1;
499 	      reg2_present = 1;
500 	    }
501 	  else
502 	    {
503 	      if (REGISTER_P (*op))
504 		reg2_present = 1;
505 
506 	      str = skip_space (str);
507 	      if (*str++ != ',')
508 		as_bad (_("`,' required"));
509 	      str = skip_space (str);
510 
511 	      reg2 = avr_operand (opcode, where, op, &str);
512 
513 	    }
514 
515 	  if (reg1_present && reg2_present)
516 	    reg2 = (reg2 & 0xf) | ((reg2 << 5) & 0x200);
517 	  else if (reg2_present)
518 	    reg2 <<= 4;
519 	}
520       if (reg1_present)
521 	reg1 <<= 4;
522       bin |= reg1 | reg2;
523     }
524 
525   /* Detect undefined combinations (like ld r31,Z+).  */
526   if (!avr_opt.all_opcodes && AVR_UNDEF_P (bin))
527     as_warn (_("undefined combination of operands"));
528 
529   if (opcode->insn_size == 2)
530     {
531       /* Warn if the previous opcode was cpse/sbic/sbis/sbrc/sbrs
532          (AVR core bug, fixed in the newer devices).  */
533 
534       if (!(avr_opt.no_skip_bug || (avr_mcu->isa & AVR_ISA_MUL))
535 	  && AVR_SKIP_P (prev))
536 	as_warn (_("skipping two-word instruction"));
537 
538       bfd_putl32 ((bfd_vma) bin, frag);
539     }
540   else
541     bfd_putl16 ((bfd_vma) bin, frag);
542 
543   prev = bin;
544   *line = str;
545   return bin;
546 }
547 
548 /* Parse one instruction operand.
549    Return operand bitmask.  Also fixups can be generated.  */
550 
551 static unsigned int
552 avr_operand (opcode, where, op, line)
553      struct avr_opcodes_s *opcode;
554      int where;
555      char *op;
556      char **line;
557 {
558   expressionS op_expr;
559   unsigned int op_mask = 0;
560   char *str = skip_space (*line);
561 
562   switch (*op)
563     {
564       /* Any register operand.  */
565     case 'w':
566     case 'd':
567     case 'r':
568     case 'a':
569     case 'v':
570       if (*str == 'r' || *str == 'R')
571 	{
572 	  char r_name[20];
573 
574 	  str = extract_word (str, r_name, sizeof (r_name));
575 	  op_mask = 0xff;
576 	  if (ISDIGIT (r_name[1]))
577 	    {
578 	      if (r_name[2] == '\0')
579 		op_mask = r_name[1] - '0';
580 	      else if (r_name[1] != '0'
581 		       && ISDIGIT (r_name[2])
582 		       && r_name[3] == '\0')
583 		op_mask = (r_name[1] - '0') * 10 + r_name[2] - '0';
584 	    }
585 	}
586       else
587 	{
588 	  op_mask = avr_get_constant (str, 31);
589 	  str = input_line_pointer;
590 	}
591 
592       if (op_mask <= 31)
593 	{
594 	  switch (*op)
595 	    {
596 	    case 'a':
597 	      if (op_mask < 16 || op_mask > 23)
598 		as_bad (_("register r16-r23 required"));
599 	      op_mask -= 16;
600 	      break;
601 
602 	    case 'd':
603 	      if (op_mask < 16)
604 		as_bad (_("register number above 15 required"));
605 	      op_mask -= 16;
606 	      break;
607 
608 	    case 'v':
609 	      if (op_mask & 1)
610 		as_bad (_("even register number required"));
611 	      op_mask >>= 1;
612 	      break;
613 
614 	    case 'w':
615 	      if ((op_mask & 1) || op_mask < 24)
616 		as_bad (_("register r24, r26, r28 or r30 required"));
617 	      op_mask = (op_mask - 24) >> 1;
618 	      break;
619 	    }
620 	  break;
621 	}
622       as_bad (_("register name or number from 0 to 31 required"));
623       break;
624 
625     case 'e':
626       {
627 	char c;
628 
629 	if (*str == '-')
630 	  {
631 	    str = skip_space (str + 1);
632 	    op_mask = 0x1002;
633 	  }
634 	c = TOLOWER (*str);
635 	if (c == 'x')
636 	  op_mask |= 0x100c;
637 	else if (c == 'y')
638 	  op_mask |= 0x8;
639 	else if (c != 'z')
640 	  as_bad (_("pointer register (X, Y or Z) required"));
641 
642 	str = skip_space (str + 1);
643 	if (*str == '+')
644 	  {
645 	    ++str;
646 	    if (op_mask & 2)
647 	      as_bad (_("cannot both predecrement and postincrement"));
648 	    op_mask |= 0x1001;
649 	  }
650 
651 	/* avr1 can do "ld r,Z" and "st Z,r" but no other pointer
652 	   registers, no predecrement, no postincrement.  */
653 	if (!avr_opt.all_opcodes && (op_mask & 0x100F)
654 	    && !(avr_mcu->isa & AVR_ISA_SRAM))
655 	  as_bad (_("addressing mode not supported"));
656       }
657       break;
658 
659     case 'z':
660       if (*str == '-')
661 	as_bad (_("can't predecrement"));
662 
663       if (! (*str == 'z' || *str == 'Z'))
664 	as_bad (_("pointer register Z required"));
665 
666       str = skip_space (str + 1);
667 
668       if (*str == '+')
669 	{
670 	  ++str;
671 	  op_mask |= 1;
672 	}
673       break;
674 
675     case 'b':
676       {
677 	char c = TOLOWER (*str++);
678 
679 	if (c == 'y')
680 	  op_mask |= 0x8;
681 	else if (c != 'z')
682 	  as_bad (_("pointer register (Y or Z) required"));
683 	str = skip_space (str);
684 	if (*str++ == '+')
685 	  {
686 	    unsigned int x;
687 	    x = avr_get_constant (str, 63);
688 	    str = input_line_pointer;
689 	    op_mask |= (x & 7) | ((x & (3 << 3)) << 7) | ((x & (1 << 5)) << 8);
690 	  }
691       }
692       break;
693 
694     case 'h':
695       str = parse_exp (str, &op_expr);
696       fix_new_exp (frag_now, where, opcode->insn_size * 2,
697 		   &op_expr, FALSE, BFD_RELOC_AVR_CALL);
698       break;
699 
700     case 'L':
701       str = parse_exp (str, &op_expr);
702       fix_new_exp (frag_now, where, opcode->insn_size * 2,
703 		   &op_expr, TRUE, BFD_RELOC_AVR_13_PCREL);
704       break;
705 
706     case 'l':
707       str = parse_exp (str, &op_expr);
708       fix_new_exp (frag_now, where, opcode->insn_size * 2,
709 		   &op_expr, TRUE, BFD_RELOC_AVR_7_PCREL);
710       break;
711 
712     case 'i':
713       str = parse_exp (str, &op_expr);
714       fix_new_exp (frag_now, where + 2, opcode->insn_size * 2,
715 		   &op_expr, FALSE, BFD_RELOC_16);
716       break;
717 
718     case 'M':
719       {
720 	bfd_reloc_code_real_type r_type;
721 
722 	input_line_pointer = str;
723 	r_type = avr_ldi_expression (&op_expr);
724 	str = input_line_pointer;
725 	fix_new_exp (frag_now, where, 3,
726 		     &op_expr, FALSE, r_type);
727       }
728       break;
729 
730     case 'n':
731       {
732 	unsigned int x;
733 
734 	x = ~avr_get_constant (str, 255);
735 	str = input_line_pointer;
736 	op_mask |= (x & 0xf) | ((x << 4) & 0xf00);
737       }
738       break;
739 
740     case 'K':
741       {
742 	unsigned int x;
743 
744 	x = avr_get_constant (str, 63);
745 	str = input_line_pointer;
746 	op_mask |= (x & 0xf) | ((x & 0x30) << 2);
747       }
748       break;
749 
750     case 'S':
751     case 's':
752       {
753 	unsigned int x;
754 
755 	x = avr_get_constant (str, 7);
756 	str = input_line_pointer;
757 	if (*op == 'S')
758 	  x <<= 4;
759 	op_mask |= x;
760       }
761       break;
762 
763     case 'P':
764       {
765 	unsigned int x;
766 
767 	x = avr_get_constant (str, 63);
768 	str = input_line_pointer;
769 	op_mask |= (x & 0xf) | ((x & 0x30) << 5);
770       }
771       break;
772 
773     case 'p':
774       {
775 	unsigned int x;
776 
777 	x = avr_get_constant (str, 31);
778 	str = input_line_pointer;
779 	op_mask |= x << 3;
780       }
781       break;
782 
783     case '?':
784       break;
785 
786     default:
787       as_bad (_("unknown constraint `%c'"), *op);
788     }
789 
790   *line = str;
791   return op_mask;
792 }
793 
794 /* GAS will call this function for each section at the end of the assembly,
795    to permit the CPU backend to adjust the alignment of a section.  */
796 
797 valueT
798 md_section_align (seg, addr)
799      asection *seg;
800      valueT addr;
801 {
802   int align = bfd_get_section_alignment (stdoutput, seg);
803   return ((addr + (1 << align) - 1) & (-1 << align));
804 }
805 
806 /* If you define this macro, it should return the offset between the
807    address of a PC relative fixup and the position from which the PC
808    relative adjustment should be made.  On many processors, the base
809    of a PC relative instruction is the next instruction, so this
810    macro would return the length of an instruction.  */
811 
812 long
813 md_pcrel_from_section (fixp, sec)
814      fixS *fixp;
815      segT sec;
816 {
817   if (fixp->fx_addsy != (symbolS *) NULL
818       && (!S_IS_DEFINED (fixp->fx_addsy)
819 	  || (S_GET_SEGMENT (fixp->fx_addsy) != sec)))
820     return 0;
821 
822   return fixp->fx_frag->fr_address + fixp->fx_where;
823 }
824 
825 /* GAS will call this for each fixup.  It should store the correct
826    value in the object file.  */
827 
828 void
829 md_apply_fix3 (fixP, valP, seg)
830      fixS *fixP;
831      valueT * valP;
832      segT seg;
833 {
834   unsigned char *where;
835   unsigned long insn;
836   long value = *valP;
837 
838   if (fixP->fx_addsy == (symbolS *) NULL)
839     fixP->fx_done = 1;
840 
841   else if (fixP->fx_pcrel)
842     {
843       segT s = S_GET_SEGMENT (fixP->fx_addsy);
844 
845       if (s == seg || s == absolute_section)
846 	{
847 	  value += S_GET_VALUE (fixP->fx_addsy);
848 	  fixP->fx_done = 1;
849 	}
850     }
851 
852   /* We don't actually support subtracting a symbol.  */
853   if (fixP->fx_subsy != (symbolS *) NULL)
854     as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex"));
855 
856   switch (fixP->fx_r_type)
857     {
858     default:
859       fixP->fx_no_overflow = 1;
860       break;
861     case BFD_RELOC_AVR_7_PCREL:
862     case BFD_RELOC_AVR_13_PCREL:
863     case BFD_RELOC_32:
864     case BFD_RELOC_16:
865     case BFD_RELOC_AVR_CALL:
866       break;
867     }
868 
869   if (fixP->fx_done)
870     {
871       /* Fetch the instruction, insert the fully resolved operand
872 	 value, and stuff the instruction back again.  */
873       where = fixP->fx_frag->fr_literal + fixP->fx_where;
874       insn = bfd_getl16 (where);
875 
876       switch (fixP->fx_r_type)
877 	{
878 	case BFD_RELOC_AVR_7_PCREL:
879 	  if (value & 1)
880 	    as_bad_where (fixP->fx_file, fixP->fx_line,
881 			  _("odd address operand: %ld"), value);
882 
883 	  /* Instruction addresses are always right-shifted by 1.  */
884 	  value >>= 1;
885 	  --value;			/* Correct PC.  */
886 
887 	  if (value < -64 || value > 63)
888 	    as_bad_where (fixP->fx_file, fixP->fx_line,
889 			  _("operand out of range: %ld"), value);
890 	  value = (value << 3) & 0x3f8;
891 	  bfd_putl16 ((bfd_vma) (value | insn), where);
892 	  break;
893 
894 	case BFD_RELOC_AVR_13_PCREL:
895 	  if (value & 1)
896 	    as_bad_where (fixP->fx_file, fixP->fx_line,
897 			  _("odd address operand: %ld"), value);
898 
899 	  /* Instruction addresses are always right-shifted by 1.  */
900 	  value >>= 1;
901 	  --value;			/* Correct PC.  */
902 
903 	  if (value < -2048 || value > 2047)
904 	    {
905 	      /* No wrap for devices with >8K of program memory.  */
906 	      if ((avr_mcu->isa & AVR_ISA_MEGA) || avr_opt.no_wrap)
907 		as_bad_where (fixP->fx_file, fixP->fx_line,
908 			      _("operand out of range: %ld"), value);
909 	    }
910 
911 	  value &= 0xfff;
912 	  bfd_putl16 ((bfd_vma) (value | insn), where);
913 	  break;
914 
915 	case BFD_RELOC_32:
916 	  bfd_putl16 ((bfd_vma) value, where);
917 	  break;
918 
919 	case BFD_RELOC_16:
920 	  bfd_putl16 ((bfd_vma) value, where);
921 	  break;
922 
923 	case BFD_RELOC_AVR_16_PM:
924 	  bfd_putl16 ((bfd_vma) (value >> 1), where);
925 	  break;
926 
927 	case BFD_RELOC_AVR_LO8_LDI:
928 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value), where);
929 	  break;
930 
931 	case -BFD_RELOC_AVR_LO8_LDI:
932 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 16), where);
933 	  break;
934 
935 	case BFD_RELOC_AVR_HI8_LDI:
936 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 8), where);
937 	  break;
938 
939 	case -BFD_RELOC_AVR_HI8_LDI:
940 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 24), where);
941 	  break;
942 
943 	case BFD_RELOC_AVR_HH8_LDI:
944 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 16), where);
945 	  break;
946 
947 	case BFD_RELOC_AVR_LO8_LDI_NEG:
948 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value), where);
949 	  break;
950 
951 	case -BFD_RELOC_AVR_LO8_LDI_NEG:
952 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 16), where);
953 	  break;
954 
955 	case BFD_RELOC_AVR_HI8_LDI_NEG:
956 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 8), where);
957 	  break;
958 
959 	case -BFD_RELOC_AVR_HI8_LDI_NEG:
960 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 24), where);
961 	  break;
962 
963 	case BFD_RELOC_AVR_HH8_LDI_NEG:
964 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 16), where);
965 	  break;
966 
967 	case BFD_RELOC_AVR_LO8_LDI_PM:
968 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 1), where);
969 	  break;
970 
971 	case BFD_RELOC_AVR_HI8_LDI_PM:
972 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 9), where);
973 	  break;
974 
975 	case BFD_RELOC_AVR_HH8_LDI_PM:
976 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 17), where);
977 	  break;
978 
979 	case BFD_RELOC_AVR_LO8_LDI_PM_NEG:
980 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 1), where);
981 	  break;
982 
983 	case BFD_RELOC_AVR_HI8_LDI_PM_NEG:
984 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 9), where);
985 	  break;
986 
987 	case BFD_RELOC_AVR_HH8_LDI_PM_NEG:
988 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 17), where);
989 	  break;
990 
991 	case BFD_RELOC_AVR_CALL:
992 	  {
993 	    unsigned long x;
994 
995 	    x = bfd_getl16 (where);
996 	    if (value & 1)
997 	      as_bad_where (fixP->fx_file, fixP->fx_line,
998 			    _("odd address operand: %ld"), value);
999 	    value >>= 1;
1000 	    x |= ((value & 0x10000) | ((value << 3) & 0x1f00000)) >> 16;
1001 	    bfd_putl16 ((bfd_vma) x, where);
1002 	    bfd_putl16 ((bfd_vma) (value & 0xffff), where + 2);
1003 	  }
1004 	  break;
1005 
1006 	default:
1007 	  as_fatal (_("line %d: unknown relocation type: 0x%x"),
1008 		    fixP->fx_line, fixP->fx_r_type);
1009 	  break;
1010 	}
1011     }
1012   else
1013     {
1014       switch (fixP->fx_r_type)
1015 	{
1016 	case -BFD_RELOC_AVR_HI8_LDI_NEG:
1017 	case -BFD_RELOC_AVR_HI8_LDI:
1018 	case -BFD_RELOC_AVR_LO8_LDI_NEG:
1019 	case -BFD_RELOC_AVR_LO8_LDI:
1020 	  as_bad_where (fixP->fx_file, fixP->fx_line,
1021 			_("only constant expression allowed"));
1022 	  fixP->fx_done = 1;
1023 	  break;
1024 	default:
1025 	  break;
1026 	}
1027     }
1028 }
1029 
1030 /* A `BFD_ASSEMBLER' GAS will call this to generate a reloc.  GAS
1031    will pass the resulting reloc to `bfd_install_relocation'.  This
1032    currently works poorly, as `bfd_install_relocation' often does the
1033    wrong thing, and instances of `tc_gen_reloc' have been written to
1034    work around the problems, which in turns makes it difficult to fix
1035    `bfd_install_relocation'.  */
1036 
1037 /* If while processing a fixup, a reloc really needs to be created
1038    then it is done here.  */
1039 
1040 arelent *
1041 tc_gen_reloc (seg, fixp)
1042      asection *seg ATTRIBUTE_UNUSED;
1043      fixS *fixp;
1044 {
1045   arelent *reloc;
1046 
1047   reloc = (arelent *) xmalloc (sizeof (arelent));
1048 
1049   reloc->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
1050   *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
1051 
1052   reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
1053   reloc->howto = bfd_reloc_type_lookup (stdoutput, fixp->fx_r_type);
1054   if (reloc->howto == (reloc_howto_type *) NULL)
1055     {
1056       as_bad_where (fixp->fx_file, fixp->fx_line,
1057 		    _("reloc %d not supported by object file format"),
1058 		    (int) fixp->fx_r_type);
1059       return NULL;
1060     }
1061 
1062   if (fixp->fx_r_type == BFD_RELOC_VTABLE_INHERIT
1063       || fixp->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
1064     reloc->address = fixp->fx_offset;
1065 
1066   reloc->addend = fixp->fx_offset;
1067 
1068   return reloc;
1069 }
1070 
1071 void
1072 md_assemble (str)
1073      char *str;
1074 {
1075   struct avr_opcodes_s *opcode;
1076   char op[11];
1077 
1078   str = skip_space (extract_word (str, op, sizeof (op)));
1079 
1080   if (!op[0])
1081     as_bad (_("can't find opcode "));
1082 
1083   opcode = (struct avr_opcodes_s *) hash_find (avr_hash, op);
1084 
1085   if (opcode == NULL)
1086     {
1087       as_bad (_("unknown opcode `%s'"), op);
1088       return;
1089     }
1090 
1091   /* Special case for opcodes with optional operands (lpm, elpm) -
1092      version with operands exists in avr_opcodes[] in the next entry.  */
1093 
1094   if (*str && *opcode->constraints == '?')
1095     ++opcode;
1096 
1097   if (!avr_opt.all_opcodes && (opcode->isa & avr_mcu->isa) != opcode->isa)
1098     as_bad (_("illegal opcode %s for mcu %s"), opcode->name, avr_mcu->name);
1099 
1100   /* We used to set input_line_pointer to the result of get_operands,
1101      but that is wrong.  Our caller assumes we don't change it.  */
1102   {
1103     char *t = input_line_pointer;
1104     avr_operands (opcode, &str);
1105     if (*skip_space (str))
1106       as_bad (_("garbage at end of line"));
1107     input_line_pointer = t;
1108   }
1109 }
1110 
1111 /* Parse ordinary expression.  */
1112 
1113 static char *
1114 parse_exp (s, op)
1115      char *s;
1116      expressionS *op;
1117 {
1118   input_line_pointer = s;
1119   expression (op);
1120   if (op->X_op == O_absent)
1121     as_bad (_("missing operand"));
1122   return input_line_pointer;
1123 }
1124 
1125 /* Parse special expressions (needed for LDI command):
1126    xx8 (address)
1127    xx8 (-address)
1128    pm_xx8 (address)
1129    pm_xx8 (-address)
1130    where xx is: hh, hi, lo.  */
1131 
1132 static bfd_reloc_code_real_type
1133 avr_ldi_expression (exp)
1134      expressionS *exp;
1135 {
1136   char *str = input_line_pointer;
1137   char *tmp;
1138   char op[8];
1139   int mod;
1140   tmp = str;
1141 
1142   str = extract_word (str, op, sizeof (op));
1143 
1144   if (op[0])
1145     {
1146       mod = (int) hash_find (avr_mod_hash, op);
1147 
1148       if (mod)
1149 	{
1150 	  int closes = 0;
1151 
1152 	  mod -= 10;
1153 	  str = skip_space (str);
1154 
1155 	  if (*str == '(')
1156 	    {
1157 	      int neg_p = 0;
1158 
1159 	      ++str;
1160 
1161 	      if (strncmp ("pm(", str, 3) == 0
1162 		  || strncmp ("-(pm(", str, 5) == 0)
1163 		{
1164 		  if (HAVE_PM_P (mod))
1165 		    {
1166 		      ++mod;
1167 		      ++closes;
1168 		    }
1169 		  else
1170 		    as_bad (_("illegal expression"));
1171 
1172 		  if (*str == '-')
1173 		    {
1174 		      neg_p = 1;
1175 		      ++closes;
1176 		      str += 5;
1177 		    }
1178 		  else
1179 		    str += 3;
1180 		}
1181 
1182 	      if (*str == '-' && *(str + 1) == '(')
1183 		{
1184 		  neg_p ^= 1;
1185 		  ++closes;
1186 		  str += 2;
1187 		}
1188 
1189 	      input_line_pointer = str;
1190 	      expression (exp);
1191 
1192 	      do
1193 		{
1194 		  if (*input_line_pointer != ')')
1195 		    {
1196 		      as_bad (_("`)' required"));
1197 		      break;
1198 		    }
1199 		  input_line_pointer++;
1200 		}
1201 	      while (closes--);
1202 
1203 	      return neg_p ? EXP_MOD_NEG_RELOC (mod) : EXP_MOD_RELOC (mod);
1204 	    }
1205 	}
1206     }
1207 
1208   input_line_pointer = tmp;
1209   expression (exp);
1210 
1211   /* Warn about expressions that fail to use lo8 ().  */
1212   if (exp->X_op == O_constant)
1213     {
1214       int x = exp->X_add_number;
1215       if (x < -255 || x > 255)
1216 	as_warn (_("constant out of 8-bit range: %d"), x);
1217     }
1218   else
1219     as_warn (_("expression possibly out of 8-bit range"));
1220 
1221   return BFD_RELOC_AVR_LO8_LDI;
1222 }
1223 
1224 /* Flag to pass `pm' mode between `avr_parse_cons_expression' and
1225    `avr_cons_fix_new'.  */
1226 static int exp_mod_pm = 0;
1227 
1228 /* Parse special CONS expression: pm (expression)
1229    which is used for addressing to a program memory.
1230    Relocation: BFD_RELOC_AVR_16_PM.  */
1231 
1232 void
1233 avr_parse_cons_expression (exp, nbytes)
1234      expressionS *exp;
1235      int nbytes;
1236 {
1237   char *tmp;
1238 
1239   exp_mod_pm = 0;
1240 
1241   tmp = input_line_pointer = skip_space (input_line_pointer);
1242 
1243   if (nbytes == 2)
1244     {
1245       char *pm_name = "pm";
1246       int len = strlen (pm_name);
1247 
1248       if (strncasecmp (input_line_pointer, pm_name, len) == 0)
1249 	{
1250 	  input_line_pointer = skip_space (input_line_pointer + len);
1251 
1252 	  if (*input_line_pointer == '(')
1253 	    {
1254 	      input_line_pointer = skip_space (input_line_pointer + 1);
1255 	      exp_mod_pm = 1;
1256 	      expression (exp);
1257 
1258 	      if (*input_line_pointer == ')')
1259 		++input_line_pointer;
1260 	      else
1261 		{
1262 		  as_bad (_("`)' required"));
1263 		  exp_mod_pm = 0;
1264 		}
1265 
1266 	      return;
1267 	    }
1268 
1269 	  input_line_pointer = tmp;
1270 	}
1271     }
1272 
1273   expression (exp);
1274 }
1275 
1276 void
1277 avr_cons_fix_new (frag, where, nbytes, exp)
1278      fragS *frag;
1279      int where;
1280      int nbytes;
1281      expressionS *exp;
1282 {
1283   if (exp_mod_pm == 0)
1284     {
1285       if (nbytes == 2)
1286 	fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_16);
1287       else if (nbytes == 4)
1288 	fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_32);
1289       else
1290 	as_bad (_("illegal %srelocation size: %d"), "", nbytes);
1291     }
1292   else
1293     {
1294       if (nbytes == 2)
1295 	fix_new_exp (frag, where, nbytes, exp, FALSE, BFD_RELOC_AVR_16_PM);
1296       else
1297 	as_bad (_("illegal %srelocation size: %d"), "`pm' ", nbytes);
1298       exp_mod_pm = 0;
1299     }
1300 }
1301