1 /* tc-xstormy16.c -- Assembler for the Sanyo XSTORMY16.
2    Copyright (C) 2000-2016 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
md_parse_option(int c ATTRIBUTE_UNUSED,const char * arg ATTRIBUTE_UNUSED)68 md_parse_option (int    c ATTRIBUTE_UNUSED,
69 		 const char * arg ATTRIBUTE_UNUSED)
70 {
71   return 0;
72 }
73 
74 void
md_show_usage(FILE * stream)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
md_begin(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 bfd_boolean skipping_fptr = FALSE;
105 
106 void
md_assemble(char * str)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
md_operand(expressionS * e)134 md_operand (expressionS * e)
135 {
136   if (*input_line_pointer != '@')
137     return;
138 
139   if (strncmp (input_line_pointer + 1, "fptr", 4) == 0)
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
xstormy16_cons_fix_new(fragS * f,int where,int nbytes,expressionS * exp,bfd_reloc_code_real_type code)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 *
xstormy16_cgen_record_fixup_exp(fragS * frag,int where,const CGEN_INSN * insn,int length,const CGEN_OPERAND * operand,int opinfo,expressionS * exp)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
md_section_align(segT segment,valueT size)278 md_section_align (segT segment, valueT size)
279 {
280   int align = bfd_get_section_alignment (stdoutput, segment);
281 
282   return ((size + (1 << align) - 1) & -(1 << align));
283 }
284 
285 symbolS *
md_undefined_symbol(char * name ATTRIBUTE_UNUSED)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
md_estimate_size_before_relax(fragS * fragP ATTRIBUTE_UNUSED,segT segment ATTRIBUTE_UNUSED)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
md_convert_frag(bfd * abfd ATTRIBUTE_UNUSED,segT sec ATTRIBUTE_UNUSED,fragS * fragP ATTRIBUTE_UNUSED)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
md_pcrel_from_section(fixS * fixP,segT sec)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
md_cgen_lookup_reloc(const CGEN_INSN * insn ATTRIBUTE_UNUSED,const CGEN_OPERAND * operand,fixS * fixP)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     case XSTORMY16_OPERAND_REL8_2:
386       fixP->fx_addnumber -= 2;
387       fixP->fx_pcrel = 1;
388       return BFD_RELOC_8_PCREL;
389 
390     case XSTORMY16_OPERAND_REL12:
391       fixP->fx_where += 2;
392       /* Fall through...  */
393     case XSTORMY16_OPERAND_REL12A:
394       fixP->fx_addnumber -= 2;
395       fixP->fx_pcrel = 1;
396       return BFD_RELOC_XSTORMY16_REL_12;
397 
398     default : /* avoid -Wall warning */
399       abort ();
400     }
401 }
402 
403 /* See whether we need to force a relocation into the output file.
404    This is used to force out switch and PC relative relocations when
405    relaxing.  */
406 
407 int
xstormy16_force_relocation(fixS * fix)408 xstormy16_force_relocation (fixS * fix)
409 {
410   if (fix->fx_r_type == BFD_RELOC_XSTORMY16_FPTR16)
411     return 1;
412 
413   return generic_force_reloc (fix);
414 }
415 
416 /* Return true if a relocation against a symbol may be replaced with
417    a relocation against section+offset.  */
418 
419 bfd_boolean
xstormy16_fix_adjustable(fixS * fixP)420 xstormy16_fix_adjustable (fixS * fixP)
421 {
422   /* We need the symbol name for the VTABLE entries.  */
423   if (fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT
424       || fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
425     return FALSE;
426 
427   if (fixP->fx_r_type == BFD_RELOC_XSTORMY16_FPTR16)
428     return FALSE;
429 
430   return TRUE;
431 }
432 
433 /* This is a copy of gas_cgen_md_apply_fix, with some enhancements to
434    do various things that would not be valid for all ports.  */
435 
436 void
xstormy16_md_apply_fix(fixS * fixP,valueT * valueP,segT seg ATTRIBUTE_UNUSED)437 xstormy16_md_apply_fix (fixS *   fixP,
438 			 valueT * valueP,
439 			 segT     seg ATTRIBUTE_UNUSED)
440 {
441   char *where = fixP->fx_frag->fr_literal + fixP->fx_where;
442   valueT value = *valueP;
443   /* Canonical name, since used a lot.  */
444   CGEN_CPU_DESC cd = gas_cgen_cpu_desc;
445 
446   /* md_cgen_lookup_reloc() will adjust this to compensate for where
447      in the opcode the relocation happens, for pcrel relocations.  We
448      have no other way of keeping track of what this offset needs to
449      be.  */
450   fixP->fx_addnumber = 0;
451 
452   /* This port has pc-relative relocs and DIFF_EXPR_OK defined, so
453      it must deal with turning a BFD_RELOC_{8,16,32,64} into a
454      BFD_RELOC_*_PCREL for the case of
455 
456 	.word something-.  */
457   if (fixP->fx_pcrel)
458     switch (fixP->fx_r_type)
459       {
460       case BFD_RELOC_8:
461 	fixP->fx_r_type = BFD_RELOC_8_PCREL;
462 	break;
463       case BFD_RELOC_16:
464 	fixP->fx_r_type = BFD_RELOC_16_PCREL;
465 	break;
466       case BFD_RELOC_32:
467 	fixP->fx_r_type = BFD_RELOC_32_PCREL;
468 	break;
469       case BFD_RELOC_64:
470 	fixP->fx_r_type = BFD_RELOC_64_PCREL;
471 	break;
472       default:
473 	break;
474       }
475 
476   if (fixP->fx_addsy == (symbolS *) NULL)
477     fixP->fx_done = 1;
478 
479   /* We don't actually support subtracting a symbol.  */
480   if (fixP->fx_subsy != (symbolS *) NULL)
481     as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex"));
482 
483   if ((int) fixP->fx_r_type >= (int) BFD_RELOC_UNUSED)
484     {
485       int opindex = (int) fixP->fx_r_type - (int) BFD_RELOC_UNUSED;
486       const CGEN_OPERAND *operand = cgen_operand_lookup_by_num (cd, opindex);
487       const char *errmsg;
488       bfd_reloc_code_real_type reloc_type;
489       const CGEN_INSN *insn = fixP->fx_cgen.insn;
490 
491       /* If the reloc has been fully resolved finish the operand here.  */
492       /* FIXME: This duplicates the capabilities of code in BFD.  */
493       if (fixP->fx_done)
494 	{
495 	  CGEN_FIELDS *fields = xmalloc (CGEN_CPU_SIZEOF_FIELDS (cd));
496 
497 	  CGEN_CPU_SET_FIELDS_BITSIZE (cd) (fields, CGEN_INSN_BITSIZE (insn));
498 	  CGEN_CPU_SET_VMA_OPERAND (cd) (cd, opindex, fields, (bfd_vma) value);
499 
500 #if CGEN_INT_INSN_P
501 	  {
502 	    CGEN_INSN_INT insn_value =
503 	      cgen_get_insn_value (cd, (unsigned char *) where,
504 				   CGEN_INSN_BITSIZE (insn));
505 
506 	    /* ??? 0 is passed for `pc'.  */
507 	    errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields,
508 						   &insn_value, (bfd_vma) 0);
509 	    cgen_put_insn_value (cd, (unsigned char *) where,
510 				 CGEN_INSN_BITSIZE (insn), insn_value);
511 	  }
512 #else
513 	  /* ??? 0 is passed for `pc'.  */
514 	  errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields,
515 						 (unsigned char *) where,
516 						 (bfd_vma) 0);
517 #endif
518 	  if (errmsg)
519 	    as_bad_where (fixP->fx_file, fixP->fx_line, "%s", errmsg);
520 
521 	  free (fields);
522 	}
523 
524       if (fixP->fx_done)
525 	return;
526 
527       /* The operand isn't fully resolved.  Determine a BFD reloc value
528 	 based on the operand information and leave it to
529 	 bfd_install_relocation.  Note that this doesn't work when
530 	 !partial_inplace.  */
531 
532       reloc_type = md_cgen_lookup_reloc (insn, operand, fixP);
533       if (reloc_type != BFD_RELOC_NONE)
534 	fixP->fx_r_type = reloc_type;
535       else
536 	{
537 	  as_bad_where (fixP->fx_file, fixP->fx_line,
538 			_("unresolved expression that must be resolved"));
539 	  fixP->fx_done = 1;
540 	  return;
541 	}
542     }
543   else if (fixP->fx_done)
544     {
545       /* We're finished with this fixup.  Install it because
546 	 bfd_install_relocation won't be called to do it.  */
547       switch (fixP->fx_r_type)
548 	{
549 	case BFD_RELOC_8:
550 	  md_number_to_chars (where, value, 1);
551 	  break;
552 	case BFD_RELOC_16:
553 	  md_number_to_chars (where, value, 2);
554 	  break;
555 	case BFD_RELOC_32:
556 	  md_number_to_chars (where, value, 4);
557 	  break;
558 	case BFD_RELOC_64:
559 	  md_number_to_chars (where, value, 8);
560 	  break;
561 	default:
562 	  as_bad_where (fixP->fx_file, fixP->fx_line,
563 			_("internal error: can't install fix for reloc type %d (`%s')"),
564 			fixP->fx_r_type, bfd_get_reloc_code_name (fixP->fx_r_type));
565 	  break;
566 	}
567     }
568   else
569     {
570       /* bfd_install_relocation will be called to finish things up.  */
571     }
572 
573   /* This is a RELA port.  Thus, it does not need to store a
574      value if it is going to make a reloc.  What's more, when
575      assembling a line like
576 
577      .byte global-0x7f00
578 
579      we'll get a spurious error message if we try to stuff 0x7f00 into
580      the byte.  */
581   if (! fixP->fx_done)
582     *valueP = 0;
583 
584   /* Tuck `value' away for use by tc_gen_reloc.
585      See the comment describing fx_addnumber in write.h.
586      This field is misnamed (or misused :-).  */
587   fixP->fx_addnumber += value;
588 }
589 
590 
591 /* Write a value out to the object file, using the appropriate endianness.  */
592 
593 void
md_number_to_chars(char * buf,valueT val,int n)594 md_number_to_chars (char * buf, valueT val, int n)
595 {
596   number_to_chars_littleendian (buf, val, n);
597 }
598 
599 const char *
md_atof(int type,char * litP,int * sizeP)600 md_atof (int type, char * litP, int * sizeP)
601 {
602   return ieee_md_atof (type, litP, sizeP, FALSE);
603 }
604