1 /* tc-xstormy16.c -- Assembler for the Sanyo XSTORMY16.
2 Copyright (C) 2000-2023 Free Software Foundation, Inc.
3
4 This file is part of GAS, the GNU Assembler.
5
6 GAS is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
10
11 GAS is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GAS; see the file COPYING. If not, write to
18 the Free Software Foundation, 51 Franklin Street - Fifth Floor,
19 Boston, MA 02110-1301, USA. */
20
21 #include "as.h"
22 #include "subsegs.h"
23 #include "symcat.h"
24 #include "opcodes/xstormy16-desc.h"
25 #include "opcodes/xstormy16-opc.h"
26 #include "cgen.h"
27
28 /* Structure to hold all of the different components describing
29 an individual instruction. */
30 typedef struct
31 {
32 const CGEN_INSN * insn;
33 const CGEN_INSN * orig_insn;
34 CGEN_FIELDS fields;
35 #if CGEN_INT_INSN_P
36 CGEN_INSN_INT buffer [1];
37 #define INSN_VALUE(buf) (*(buf))
38 #else
39 unsigned char buffer [CGEN_MAX_INSN_SIZE];
40 #define INSN_VALUE(buf) (buf)
41 #endif
42 char * addr;
43 fragS * frag;
44 int num_fixups;
45 fixS * fixups [GAS_CGEN_MAX_FIXUPS];
46 int indices [MAX_OPERAND_INSTANCES];
47 }
48 xstormy16_insn;
49
50 const char comment_chars[] = ";";
51 const char line_comment_chars[] = "#";
52 const char line_separator_chars[] = "|";
53 const char EXP_CHARS[] = "eE";
54 const char FLT_CHARS[] = "dD";
55
56 #define O_fptr_symbol (O_max + 1)
57
58 #define XSTORMY16_SHORTOPTS ""
59 const char * md_shortopts = XSTORMY16_SHORTOPTS;
60
61 struct option md_longopts[] =
62 {
63 {NULL, no_argument, NULL, 0}
64 };
65 size_t md_longopts_size = sizeof (md_longopts);
66
67 int
68 md_parse_option (int c ATTRIBUTE_UNUSED,
69 const char * arg ATTRIBUTE_UNUSED)
70 {
71 return 0;
72 }
73
74 void
75 md_show_usage (FILE * stream)
76 {
77 fprintf (stream, _(" XSTORMY16 specific command line options:\n"));
78 }
79
80 /* The target specific pseudo-ops which we support. */
81 const pseudo_typeS md_pseudo_table[] =
82 {
83 { "word", cons, 4 },
84 { NULL, NULL, 0 }
85 };
86
87
88 void
89 md_begin (void)
90 {
91 /* Initialize the `cgen' interface. */
92
93 /* Set the machine number and endian. */
94 gas_cgen_cpu_desc = xstormy16_cgen_cpu_open (CGEN_CPU_OPEN_MACHS, 0,
95 CGEN_CPU_OPEN_ENDIAN,
96 CGEN_ENDIAN_LITTLE,
97 CGEN_CPU_OPEN_END);
98 xstormy16_cgen_init_asm (gas_cgen_cpu_desc);
99
100 /* This is a callback from cgen to gas to parse operands. */
101 cgen_set_parse_operand_fn (gas_cgen_cpu_desc, gas_cgen_parse_operand);
102 }
103
104 static bool skipping_fptr = false;
105
106 void
107 md_assemble (char * str)
108 {
109 xstormy16_insn insn;
110 char * errmsg;
111
112 /* Make sure that if we had an erroneous input line which triggered
113 the skipping_fptr boolean that it does not affect following lines. */
114 skipping_fptr = false;
115
116 /* Initialize GAS's cgen interface for a new instruction. */
117 gas_cgen_init_parse ();
118
119 insn.insn = xstormy16_cgen_assemble_insn
120 (gas_cgen_cpu_desc, str, & insn.fields, insn.buffer, & errmsg);
121
122 if (!insn.insn)
123 {
124 as_bad ("%s", errmsg);
125 return;
126 }
127
128 /* Doesn't really matter what we pass for RELAX_P here. */
129 gas_cgen_finish_insn (insn.insn, insn.buffer,
130 CGEN_FIELDS_BITSIZE (& insn.fields), 0, NULL);
131 }
132
133 void
134 md_operand (expressionS * e)
135 {
136 if (*input_line_pointer != '@')
137 return;
138
139 if (startswith (input_line_pointer + 1, "fptr"))
140 {
141 input_line_pointer += 5;
142 SKIP_WHITESPACE ();
143 if (*input_line_pointer != '(')
144 {
145 as_bad (_("Expected '('"));
146 goto err;
147 }
148 input_line_pointer++;
149
150 expression (e);
151
152 if (*input_line_pointer != ')')
153 {
154 as_bad (_("Missing ')'"));
155 goto err;
156 }
157 input_line_pointer++;
158 SKIP_WHITESPACE ();
159
160 if (e->X_op != O_symbol)
161 as_bad (_("Not a symbolic expression"));
162 else if (* input_line_pointer == '-')
163 /* We are computing the difference of two function pointers
164 like this:
165
166 .hword @fptr (foo) - @fptr (bar)
167
168 In this situation we do not want to generate O_fptr_symbol
169 operands because the result is an absolute value, not a
170 function pointer.
171
172 We need to make the check here, rather than when the fixup
173 is generated as the function names (foo & bar in the above
174 example) might be local symbols and we want the expression
175 to be evaluated now. This kind of thing can happen when
176 gcc is generating computed gotos. */
177 skipping_fptr = true;
178 else if (skipping_fptr)
179 skipping_fptr = false;
180 else
181 e->X_op = O_fptr_symbol;
182 }
183
184 return;
185 err:
186 ignore_rest_of_line ();
187 }
188
189 /* Called while parsing data to create a fixup.
190 Create BFD_RELOC_XSTORMY16_FPTR16 relocations. */
191
192 void
193 xstormy16_cons_fix_new (fragS *f,
194 int where,
195 int nbytes,
196 expressionS *exp,
197 bfd_reloc_code_real_type code)
198 {
199 if (exp->X_op == O_fptr_symbol)
200 {
201 switch (nbytes)
202 {
203 case 4:
204 /* This can happen when gcc is generating debug output.
205 For example it can create a stab with the address of
206 a function:
207
208 .stabs "foo:F(0,21)",36,0,0,@fptr(foo)
209
210 Since this does not involve switching code pages, we
211 just allow the reloc to be generated without any
212 @fptr behaviour. */
213 exp->X_op = O_symbol;
214 code = BFD_RELOC_32;
215 break;
216
217 case 2:
218 exp->X_op = O_symbol;
219 code = BFD_RELOC_XSTORMY16_FPTR16;
220 break;
221
222 default:
223 as_bad (_("unsupported fptr fixup size %d"), nbytes);
224 return;
225 }
226 }
227 else if (nbytes == 1)
228 code = BFD_RELOC_8;
229 else if (nbytes == 2)
230 code = BFD_RELOC_16;
231 else if (nbytes == 4)
232 code = BFD_RELOC_32;
233 else
234 {
235 as_bad (_("unsupported fixup size %d"), nbytes);
236 return;
237 }
238
239 fix_new_exp (f, where, nbytes, exp, 0, code);
240 }
241
242 /* Called while parsing an instruction to create a fixup.
243 Create BFD_RELOC_XSTORMY16_FPTR16 relocations. */
244
245 fixS *
246 xstormy16_cgen_record_fixup_exp (fragS * frag,
247 int where,
248 const CGEN_INSN * insn,
249 int length,
250 const CGEN_OPERAND * operand,
251 int opinfo,
252 expressionS * exp)
253 {
254 fixS *fixP;
255 operatorT op = exp->X_op;
256
257 if (op == O_fptr_symbol)
258 exp->X_op = O_symbol;
259
260 fixP = gas_cgen_record_fixup_exp (frag, where, insn, length,
261 operand, opinfo, exp);
262
263 if (op == O_fptr_symbol)
264 {
265 if (operand->type != XSTORMY16_OPERAND_IMM16)
266 as_bad (_("unsupported fptr fixup"));
267 else
268 {
269 fixP->fx_r_type = BFD_RELOC_XSTORMY16_FPTR16;
270 fixP->fx_where += 2;
271 }
272 }
273
274 return fixP;
275 }
276
277 valueT
278 md_section_align (segT segment, valueT size)
279 {
280 int align = bfd_section_alignment (segment);
281
282 return ((size + (1 << align) - 1) & -(1 << align));
283 }
284
285 symbolS *
286 md_undefined_symbol (char * name ATTRIBUTE_UNUSED)
287 {
288 return 0;
289 }
290
291 /* Return an initial guess of the length by which a fragment must grow to
292 hold a branch to reach its destination.
293 Also updates fr_type/fr_subtype as necessary.
294
295 Called just before doing relaxation.
296 Any symbol that is now undefined will not become defined.
297 The guess for fr_var is ACTUALLY the growth beyond fr_fix.
298 Whatever we do to grow fr_fix or fr_var contributes to our returned value.
299 Although it may not be explicit in the frag, pretend fr_var starts with a
300 0 value. */
301
302 int
303 md_estimate_size_before_relax (fragS * fragP ATTRIBUTE_UNUSED,
304 segT segment ATTRIBUTE_UNUSED)
305 {
306 /* No assembler relaxation is defined (or necessary) for this port. */
307 abort ();
308 }
309
310 /* *fragP has been relaxed to its final size, and now needs to have
311 the bytes inside it modified to conform to the new size.
312
313 Called after relaxation is finished.
314 fragP->fr_type == rs_machine_dependent.
315 fragP->fr_subtype is the subtype of what the address relaxed to. */
316
317 void
318 md_convert_frag (bfd * abfd ATTRIBUTE_UNUSED,
319 segT sec ATTRIBUTE_UNUSED,
320 fragS * fragP ATTRIBUTE_UNUSED)
321 {
322 /* No assembler relaxation is defined (or necessary) for this port. */
323 abort ();
324 }
325
326 /* Functions concerning relocs. */
327
328 /* The location from which a PC relative jump should be calculated,
329 given a PC relative reloc. */
330
331 long
332 md_pcrel_from_section (fixS * fixP, segT sec)
333 {
334 if ((fixP->fx_addsy != (symbolS *) NULL
335 && (! S_IS_DEFINED (fixP->fx_addsy)
336 || S_GET_SEGMENT (fixP->fx_addsy) != sec))
337 || xstormy16_force_relocation (fixP))
338 /* The symbol is undefined,
339 or it is defined but not in this section,
340 or the relocation will be relative to this symbol not the section symbol.
341 Let the linker figure it out. */
342 return 0;
343
344 return fixP->fx_frag->fr_address + fixP->fx_where;
345 }
346
347 /* Return the bfd reloc type for OPERAND of INSN at fixup FIXP.
348 Returns BFD_RELOC_NONE if no reloc type can be found.
349 *FIXP may be modified if desired. */
350
351 bfd_reloc_code_real_type
352 md_cgen_lookup_reloc (const CGEN_INSN * insn ATTRIBUTE_UNUSED,
353 const CGEN_OPERAND * operand,
354 fixS * fixP)
355 {
356 switch (operand->type)
357 {
358 case XSTORMY16_OPERAND_IMM2:
359 case XSTORMY16_OPERAND_IMM3:
360 case XSTORMY16_OPERAND_IMM3B:
361 case XSTORMY16_OPERAND_IMM4:
362 case XSTORMY16_OPERAND_HMEM8:
363 return BFD_RELOC_NONE;
364
365 case XSTORMY16_OPERAND_IMM12:
366 fixP->fx_where += 2;
367 return BFD_RELOC_XSTORMY16_12;
368
369 case XSTORMY16_OPERAND_IMM8:
370 case XSTORMY16_OPERAND_LMEM8:
371 return fixP->fx_pcrel ? BFD_RELOC_8_PCREL : BFD_RELOC_8;
372
373 case XSTORMY16_OPERAND_IMM16:
374 /* This might have been processed at parse time. */
375 fixP->fx_where += 2;
376 if (fixP->fx_cgen.opinfo && fixP->fx_cgen.opinfo != BFD_RELOC_NONE)
377 return fixP->fx_cgen.opinfo;
378 return fixP->fx_pcrel ? BFD_RELOC_16_PCREL : BFD_RELOC_16;
379
380 case XSTORMY16_OPERAND_ABS24:
381 return BFD_RELOC_XSTORMY16_24;
382
383 case XSTORMY16_OPERAND_REL8_4:
384 fixP->fx_addnumber -= 2;
385 /* Fall through. */
386 case XSTORMY16_OPERAND_REL8_2:
387 fixP->fx_addnumber -= 2;
388 fixP->fx_pcrel = 1;
389 return BFD_RELOC_8_PCREL;
390
391 case XSTORMY16_OPERAND_REL12:
392 fixP->fx_where += 2;
393 /* Fall through. */
394 case XSTORMY16_OPERAND_REL12A:
395 fixP->fx_addnumber -= 2;
396 fixP->fx_pcrel = 1;
397 return BFD_RELOC_XSTORMY16_REL_12;
398
399 default : /* avoid -Wall warning */
400 abort ();
401 }
402 }
403
404 /* See whether we need to force a relocation into the output file.
405 This is used to force out switch and PC relative relocations when
406 relaxing. */
407
408 int
409 xstormy16_force_relocation (fixS * fix)
410 {
411 if (fix->fx_r_type == BFD_RELOC_XSTORMY16_FPTR16)
412 return 1;
413
414 return generic_force_reloc (fix);
415 }
416
417 /* Return true if a relocation against a symbol may be replaced with
418 a relocation against section+offset. */
419
420 bool
421 xstormy16_fix_adjustable (fixS * fixP)
422 {
423 /* We need the symbol name for the VTABLE entries. */
424 if (fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT
425 || fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
426 return false;
427
428 if (fixP->fx_r_type == BFD_RELOC_XSTORMY16_FPTR16)
429 return false;
430
431 return true;
432 }
433
434 /* This is a copy of gas_cgen_md_apply_fix, with some enhancements to
435 do various things that would not be valid for all ports. */
436
437 void
438 xstormy16_md_apply_fix (fixS * fixP,
439 valueT * valueP,
440 segT seg ATTRIBUTE_UNUSED)
441 {
442 char *where = fixP->fx_frag->fr_literal + fixP->fx_where;
443 valueT value = *valueP;
444 /* Canonical name, since used a lot. */
445 CGEN_CPU_DESC cd = gas_cgen_cpu_desc;
446
447 /* md_cgen_lookup_reloc() will adjust this to compensate for where
448 in the opcode the relocation happens, for pcrel relocations. We
449 have no other way of keeping track of what this offset needs to
450 be. */
451 fixP->fx_addnumber = 0;
452
453 /* This port has pc-relative relocs and DIFF_EXPR_OK defined, so
454 it must deal with turning a BFD_RELOC_{8,16,32,64} into a
455 BFD_RELOC_*_PCREL for the case of
456
457 .word something-. */
458 if (fixP->fx_pcrel)
459 switch (fixP->fx_r_type)
460 {
461 case BFD_RELOC_8:
462 fixP->fx_r_type = BFD_RELOC_8_PCREL;
463 break;
464 case BFD_RELOC_16:
465 fixP->fx_r_type = BFD_RELOC_16_PCREL;
466 break;
467 case BFD_RELOC_32:
468 fixP->fx_r_type = BFD_RELOC_32_PCREL;
469 break;
470 case BFD_RELOC_64:
471 fixP->fx_r_type = BFD_RELOC_64_PCREL;
472 break;
473 default:
474 break;
475 }
476
477 if (fixP->fx_addsy == (symbolS *) NULL)
478 fixP->fx_done = 1;
479
480 /* We don't actually support subtracting a symbol. */
481 if (fixP->fx_subsy != (symbolS *) NULL)
482 as_bad_subtract (fixP);
483
484 if ((int) fixP->fx_r_type >= (int) BFD_RELOC_UNUSED)
485 {
486 int opindex = (int) fixP->fx_r_type - (int) BFD_RELOC_UNUSED;
487 const CGEN_OPERAND *operand = cgen_operand_lookup_by_num (cd, opindex);
488 const char *errmsg;
489 bfd_reloc_code_real_type reloc_type;
490 const CGEN_INSN *insn = fixP->fx_cgen.insn;
491
492 /* If the reloc has been fully resolved finish the operand here. */
493 /* FIXME: This duplicates the capabilities of code in BFD. */
494 if (fixP->fx_done)
495 {
496 CGEN_FIELDS *fields = xmalloc (CGEN_CPU_SIZEOF_FIELDS (cd));
497
498 CGEN_CPU_SET_FIELDS_BITSIZE (cd) (fields, CGEN_INSN_BITSIZE (insn));
499 CGEN_CPU_SET_VMA_OPERAND (cd) (cd, opindex, fields, (bfd_vma) value);
500
501 #if CGEN_INT_INSN_P
502 {
503 CGEN_INSN_INT insn_value =
504 cgen_get_insn_value (cd, (unsigned char *) where,
505 CGEN_INSN_BITSIZE (insn),
506 gas_cgen_cpu_desc->insn_endian);
507
508 /* ??? 0 is passed for `pc'. */
509 errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields,
510 &insn_value, (bfd_vma) 0);
511 cgen_put_insn_value (cd, (unsigned char *) where,
512 CGEN_INSN_BITSIZE (insn), insn_value,
513 gas_cgen_cpu_desc->insn_endian);
514 }
515 #else
516 /* ??? 0 is passed for `pc'. */
517 errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields,
518 (unsigned char *) where,
519 (bfd_vma) 0);
520 #endif
521 if (errmsg)
522 as_bad_where (fixP->fx_file, fixP->fx_line, "%s", errmsg);
523
524 free (fields);
525 }
526
527 if (fixP->fx_done)
528 return;
529
530 /* The operand isn't fully resolved. Determine a BFD reloc value
531 based on the operand information and leave it to
532 bfd_install_relocation. Note that this doesn't work when
533 !partial_inplace. */
534
535 reloc_type = md_cgen_lookup_reloc (insn, operand, fixP);
536 if (reloc_type != BFD_RELOC_NONE)
537 fixP->fx_r_type = reloc_type;
538 else
539 {
540 as_bad_where (fixP->fx_file, fixP->fx_line,
541 _("unresolved expression that must be resolved"));
542 fixP->fx_done = 1;
543 return;
544 }
545 }
546 else if (fixP->fx_done)
547 {
548 /* We're finished with this fixup. Install it because
549 bfd_install_relocation won't be called to do it. */
550 switch (fixP->fx_r_type)
551 {
552 case BFD_RELOC_8:
553 md_number_to_chars (where, value, 1);
554 break;
555 case BFD_RELOC_16:
556 md_number_to_chars (where, value, 2);
557 break;
558 case BFD_RELOC_32:
559 md_number_to_chars (where, value, 4);
560 break;
561 case BFD_RELOC_64:
562 md_number_to_chars (where, value, 8);
563 break;
564 default:
565 as_bad_where (fixP->fx_file, fixP->fx_line,
566 _("internal error: can't install fix for reloc type %d (`%s')"),
567 fixP->fx_r_type, bfd_get_reloc_code_name (fixP->fx_r_type));
568 break;
569 }
570 }
571 else
572 {
573 /* bfd_install_relocation will be called to finish things up. */
574 }
575
576 /* This is a RELA port. Thus, it does not need to store a
577 value if it is going to make a reloc. What's more, when
578 assembling a line like
579
580 .byte global-0x7f00
581
582 we'll get a spurious error message if we try to stuff 0x7f00 into
583 the byte. */
584 if (! fixP->fx_done)
585 *valueP = 0;
586
587 /* Tuck `value' away for use by tc_gen_reloc.
588 See the comment describing fx_addnumber in write.h.
589 This field is misnamed (or misused :-). */
590 fixP->fx_addnumber += value;
591 }
592
593
594 /* Write a value out to the object file, using the appropriate endianness. */
595
596 void
597 md_number_to_chars (char * buf, valueT val, int n)
598 {
599 number_to_chars_littleendian (buf, val, n);
600 }
601
602 const char *
603 md_atof (int type, char * litP, int * sizeP)
604 {
605 return ieee_md_atof (type, litP, sizeP, false);
606 }