1 /* tc-pj.c -- Assemble code for Pico Java
2    Copyright (C) 1999-2020 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 /* Contributed by Steve Chamberlain of Transmeta <sac@pobox.com>.  */
22 
23 #include "as.h"
24 #include "safe-ctype.h"
25 #include "opcode/pj.h"
26 
27 extern const pj_opc_info_t pj_opc_info[512];
28 
29 const char comment_chars[]        = "!/";
30 const char line_separator_chars[] = ";";
31 const char line_comment_chars[]   = "/!#";
32 
33 static int pending_reloc;
34 static struct hash_control *opcode_hash_control;
35 
36 static void
little(int ignore ATTRIBUTE_UNUSED)37 little (int ignore ATTRIBUTE_UNUSED)
38 {
39   target_big_endian = 0;
40 }
41 
42 static void
big(int ignore ATTRIBUTE_UNUSED)43 big (int ignore ATTRIBUTE_UNUSED)
44 {
45   target_big_endian = 1;
46 }
47 
48 const pseudo_typeS md_pseudo_table[] =
49 {
50   {"ml",    little, 0},
51   {"mb",    big,    0},
52   {0, 0, 0}
53 };
54 
55 const char FLT_CHARS[] = "rRsSfFdDxXpP";
56 const char EXP_CHARS[] = "eE";
57 
58 void
md_operand(expressionS * op)59 md_operand (expressionS *op)
60 {
61   if (strncmp (input_line_pointer, "%hi16", 5) == 0)
62     {
63       if (pending_reloc)
64 	as_bad (_("confusing relocation expressions"));
65       pending_reloc = BFD_RELOC_PJ_CODE_HI16;
66       input_line_pointer += 5;
67       expression (op);
68     }
69 
70   if (strncmp (input_line_pointer, "%lo16", 5) == 0)
71     {
72       if (pending_reloc)
73 	as_bad (_("confusing relocation expressions"));
74       pending_reloc = BFD_RELOC_PJ_CODE_LO16;
75       input_line_pointer += 5;
76       expression (op);
77     }
78 }
79 
80 /* Parse an expression and then restore the input line pointer.  */
81 
82 static char *
parse_exp_save_ilp(char * s,expressionS * op)83 parse_exp_save_ilp (char *s, expressionS *op)
84 {
85   char *save = input_line_pointer;
86 
87   input_line_pointer = s;
88   expression (op);
89   s = input_line_pointer;
90   input_line_pointer = save;
91   return s;
92 }
93 
94 /* This is called by emit_expr via TC_CONS_FIX_NEW when creating a
95    reloc for a cons.  We could use the definition there, except that
96    we want to handle magic pending reloc expressions specially.  */
97 
98 void
pj_cons_fix_new_pj(fragS * frag,int where,int nbytes,expressionS * exp,bfd_reloc_code_real_type r ATTRIBUTE_UNUSED)99 pj_cons_fix_new_pj (fragS *frag, int where, int nbytes, expressionS *exp,
100 		    bfd_reloc_code_real_type r ATTRIBUTE_UNUSED)
101 {
102   static int rv[5][2] =
103   { { 0, 0 },
104     { BFD_RELOC_8, BFD_RELOC_8 },
105     { BFD_RELOC_PJ_CODE_DIR16, BFD_RELOC_16 },
106     { 0, 0 },
107     { BFD_RELOC_PJ_CODE_DIR32, BFD_RELOC_32 }};
108 
109   fix_new_exp (frag, where, nbytes, exp, 0,
110 	       pending_reloc ? pending_reloc
111 	       : rv[nbytes][(now_seg->flags & SEC_CODE) ? 0 : 1]);
112 
113   pending_reloc = 0;
114 }
115 
116 /* Turn a reloc description character from the pj-opc.h table into
117    code which BFD can handle.  */
118 
119 static int
c_to_r(int x)120 c_to_r (int x)
121 {
122   switch (x)
123     {
124     case O_R8:
125       return BFD_RELOC_8_PCREL;
126     case O_U8:
127     case O_8:
128       return BFD_RELOC_8;
129     case O_R16:
130       return BFD_RELOC_PJ_CODE_REL16;
131     case O_U16:
132     case O_16:
133       return BFD_RELOC_PJ_CODE_DIR16;
134     case O_R32:
135       return BFD_RELOC_PJ_CODE_REL32;
136     case O_32:
137       return BFD_RELOC_PJ_CODE_DIR32;
138     }
139   abort ();
140   return 0;
141 }
142 
143 /* Handler for the ipush fake opcode,
144    turns ipush <foo> into sipush lo16<foo>, sethi hi16<foo>.  */
145 
146 static void
ipush_code(pj_opc_info_t * opcode ATTRIBUTE_UNUSED,char * str)147 ipush_code (pj_opc_info_t *opcode ATTRIBUTE_UNUSED, char *str)
148 {
149   char *b = frag_more (6);
150   expressionS arg;
151 
152   b[0] = 0x11;
153   b[3] = 0xed;
154   parse_exp_save_ilp (str + 1, &arg);
155   if (pending_reloc)
156     {
157       as_bad (_("can't have relocation for ipush"));
158       pending_reloc = 0;
159     }
160 
161   fix_new_exp (frag_now, b - frag_now->fr_literal + 1, 2,
162 	       &arg, 0, BFD_RELOC_PJ_CODE_DIR16);
163   fix_new_exp (frag_now, b - frag_now->fr_literal + 4, 2,
164 	       &arg, 0, BFD_RELOC_PJ_CODE_HI16);
165 }
166 
167 /* Insert names into the opcode table which are really mini macros,
168    not opcodes.  The fakeness is indicated with an opcode of -1.  */
169 
170 static void
fake_opcode(const char * name,void (* func)(struct pj_opc_info_t *,char *))171 fake_opcode (const char *name,
172 	     void (*func) (struct pj_opc_info_t *, char *))
173 {
174   pj_opc_info_t * fake = XNEW (pj_opc_info_t);
175 
176   fake->opcode = -1;
177   fake->opcode_next = -1;
178   fake->u.func = func;
179   hash_insert (opcode_hash_control, name, (char *) fake);
180 }
181 
182 /* Enter another entry into the opcode hash table so the same opcode
183    can have another name.  */
184 
185 static void
alias(const char * new_name,const char * old)186 alias (const char *new_name, const char *old)
187 {
188   hash_insert (opcode_hash_control, new_name,
189 	       (char *) hash_find (opcode_hash_control, old));
190 }
191 
192 /* This function is called once, at assembler startup time.  It sets
193    up the hash table with all the opcodes in it, and also initializes
194    some aliases for compatibility with other assemblers.  */
195 
196 void
md_begin(void)197 md_begin (void)
198 {
199   const pj_opc_info_t *opcode;
200   opcode_hash_control = hash_new ();
201 
202   /* Insert names into hash table.  */
203   for (opcode = pj_opc_info; opcode->u.name; opcode++)
204     hash_insert (opcode_hash_control, opcode->u.name, (char *) opcode);
205 
206   /* Insert the only fake opcode.  */
207   fake_opcode ("ipush", ipush_code);
208 
209   /* Add some aliases for opcode names.  */
210   alias ("ifeq_s", "ifeq");
211   alias ("ifne_s", "ifne");
212   alias ("if_icmpge_s", "if_icmpge");
213   alias ("if_icmpne_s", "if_icmpne");
214   alias ("if_icmpeq_s", "if_icmpeq");
215   alias ("if_icmpgt_s", "if_icmpgt");
216   alias ("goto_s", "goto");
217 
218   bfd_set_arch_mach (stdoutput, TARGET_ARCH, 0);
219 }
220 
221 /* This is the guts of the machine-dependent assembler.  STR points to
222    a machine dependent instruction.  This function is supposed to emit
223    the frags/bytes it assembles to.  */
224 
225 void
md_assemble(char * str)226 md_assemble (char *str)
227 {
228   char *op_start;
229   char *op_end;
230 
231   pj_opc_info_t *opcode;
232   char *output;
233   int idx = 0;
234   char pend;
235 
236   int nlen = 0;
237 
238   /* Drop leading whitespace.  */
239   while (*str == ' ')
240     str++;
241 
242   /* Find the op code end.  */
243   op_start = str;
244   for (op_end = str;
245        *op_end && !is_end_of_line[*op_end & 0xff] && *op_end != ' ';
246        op_end++)
247     nlen++;
248 
249   pend = *op_end;
250   *op_end = 0;
251 
252   if (nlen == 0)
253     as_bad (_("can't find opcode "));
254 
255   opcode = (pj_opc_info_t *) hash_find (opcode_hash_control, op_start);
256   *op_end = pend;
257 
258   if (opcode == NULL)
259     {
260       as_bad (_("unknown opcode %s"), op_start);
261       return;
262     }
263 
264   dwarf2_emit_insn (0);
265   if (opcode->opcode == -1)
266     {
267       /* It's a fake opcode.  Dig out the args and pretend that was
268          what we were passed.  */
269       (*opcode->u.func) (opcode, op_end);
270     }
271   else
272     {
273       int an;
274 
275       output = frag_more (opcode->len);
276       output[idx++] = opcode->opcode;
277 
278       if (opcode->opcode_next != -1)
279 	output[idx++] = opcode->opcode_next;
280 
281       for (an = 0; opcode->arg[an]; an++)
282 	{
283 	  expressionS arg;
284 
285 	  if (*op_end == ',' && an != 0)
286 	    op_end++;
287 
288 	  if (*op_end == 0)
289 	    as_bad (_("expected expression"));
290 
291 	  op_end = parse_exp_save_ilp (op_end, &arg);
292 
293 	  fix_new_exp (frag_now,
294 		       output - frag_now->fr_literal + idx,
295 		       ASIZE (opcode->arg[an]),
296 		       &arg,
297 		       PCREL (opcode->arg[an]),
298 		       pending_reloc ? pending_reloc : c_to_r (opcode->arg[an]));
299 
300 	  idx += ASIZE (opcode->arg[an]);
301 	  pending_reloc = 0;
302 	}
303 
304       while (ISSPACE (*op_end))
305 	op_end++;
306 
307       if (*op_end != 0)
308 	as_warn (_("extra stuff on line ignored"));
309 
310     }
311 
312   if (pending_reloc)
313     as_bad (_("Something forgot to clean up\n"));
314 }
315 
316 const char *
md_atof(int type,char * litP,int * sizeP)317 md_atof (int type, char *litP, int *sizeP)
318 {
319   return ieee_md_atof (type, litP, sizeP, target_big_endian);
320 }
321 
322 const char *md_shortopts = "";
323 
324 struct option md_longopts[] =
325 {
326 #define OPTION_LITTLE (OPTION_MD_BASE)
327 #define OPTION_BIG    (OPTION_LITTLE + 1)
328 
329   {"little", no_argument, NULL, OPTION_LITTLE},
330   {"big", no_argument, NULL, OPTION_BIG},
331   {NULL, no_argument, NULL, 0}
332 };
333 size_t md_longopts_size = sizeof (md_longopts);
334 
335 int
md_parse_option(int c,const char * arg ATTRIBUTE_UNUSED)336 md_parse_option (int c, const char *arg ATTRIBUTE_UNUSED)
337 {
338   switch (c)
339     {
340     case OPTION_LITTLE:
341       little (0);
342       break;
343     case OPTION_BIG:
344       big (0);
345       break;
346     default:
347       return 0;
348     }
349   return 1;
350 }
351 
352 void
md_show_usage(FILE * stream)353 md_show_usage (FILE *stream)
354 {
355   fprintf (stream, _("\
356 PJ options:\n\
357 -little			generate little endian code\n\
358 -big			generate big endian code\n"));
359 }
360 
361 /* Apply a fixup to the object file.  */
362 
363 void
md_apply_fix(fixS * fixP,valueT * valP,segT seg ATTRIBUTE_UNUSED)364 md_apply_fix (fixS *fixP, valueT * valP, segT seg ATTRIBUTE_UNUSED)
365 {
366   char *buf = fixP->fx_where + fixP->fx_frag->fr_literal;
367   long val = *valP;
368   long max, min;
369 
370   max = min = 0;
371   switch (fixP->fx_r_type)
372     {
373     case BFD_RELOC_VTABLE_INHERIT:
374     case BFD_RELOC_VTABLE_ENTRY:
375       fixP->fx_done = 0;
376       return;
377 
378     case BFD_RELOC_PJ_CODE_REL16:
379       if (val < -0x8000 || val >= 0x7fff)
380 	as_bad_where (fixP->fx_file, fixP->fx_line, _("pcrel too far"));
381       buf[0] |= (val >> 8) & 0xff;
382       buf[1] = val & 0xff;
383       break;
384 
385     case BFD_RELOC_PJ_CODE_HI16:
386       *buf++ = val >> 24;
387       *buf++ = val >> 16;
388       fixP->fx_addnumber = val & 0xffff;
389       break;
390 
391     case BFD_RELOC_PJ_CODE_DIR16:
392     case BFD_RELOC_PJ_CODE_LO16:
393       *buf++ = val >> 8;
394       *buf++ = val >> 0;
395 
396       max = 0xffff;
397       min = -0xffff;
398       break;
399 
400     case BFD_RELOC_8:
401       max = 0xff;
402       min = -0xff;
403       *buf++ = val;
404       break;
405 
406     case BFD_RELOC_PJ_CODE_DIR32:
407       *buf++ = val >> 24;
408       *buf++ = val >> 16;
409       *buf++ = val >> 8;
410       *buf++ = val >> 0;
411       break;
412 
413     case BFD_RELOC_32:
414       if (target_big_endian)
415 	{
416 	  *buf++ = val >> 24;
417 	  *buf++ = val >> 16;
418 	  *buf++ = val >> 8;
419 	  *buf++ = val >> 0;
420 	}
421       else
422 	{
423 	  *buf++ = val >> 0;
424 	  *buf++ = val >> 8;
425 	  *buf++ = val >> 16;
426 	  *buf++ = val >> 24;
427 	}
428       break;
429 
430     case BFD_RELOC_16:
431       if (target_big_endian)
432 	{
433 	  *buf++ = val >> 8;
434 	  *buf++ = val >> 0;
435 	}
436       else
437 	{
438 	  *buf++ = val >> 0;
439 	  *buf++ = val >> 8;
440 	}
441       break;
442 
443     case BFD_RELOC_PJ_CODE_REL32:
444       fixP->fx_done = 0;
445       return;
446 
447     default:
448       abort ();
449     }
450 
451   if (max != 0 && (val < min || val > max))
452     as_bad_where (fixP->fx_file, fixP->fx_line, _("offset out of range"));
453 
454   if (fixP->fx_addsy == NULL && fixP->fx_pcrel == 0)
455     fixP->fx_done = 1;
456 }
457 
458 /* Put number into target byte order.  Always put values in an
459    executable section into big endian order.  */
460 
461 void
md_number_to_chars(char * ptr,valueT use,int nbytes)462 md_number_to_chars (char *ptr, valueT use, int nbytes)
463 {
464   if (target_big_endian || now_seg->flags & SEC_CODE)
465     number_to_chars_bigendian (ptr, use, nbytes);
466   else
467     number_to_chars_littleendian (ptr, use, nbytes);
468 }
469 
470 /* Translate internal representation of relocation info to BFD target
471    format.  */
472 
473 arelent *
tc_gen_reloc(asection * section ATTRIBUTE_UNUSED,fixS * fixp)474 tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS *fixp)
475 {
476   arelent *rel;
477   bfd_reloc_code_real_type r_type;
478 
479   rel = XNEW (arelent);
480   rel->sym_ptr_ptr = XNEW (asymbol *);
481   *rel->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
482   rel->address = fixp->fx_frag->fr_address + fixp->fx_where;
483 
484   r_type = fixp->fx_r_type;
485   rel->addend = fixp->fx_addnumber;
486   rel->howto = bfd_reloc_type_lookup (stdoutput, r_type);
487 
488   if (rel->howto == NULL)
489     {
490       as_bad_where (fixp->fx_file, fixp->fx_line,
491 		    _("Cannot represent relocation type %s"),
492 		    bfd_get_reloc_code_name (r_type));
493       /* Set howto to a garbage value so that we can keep going.  */
494       rel->howto = bfd_reloc_type_lookup (stdoutput, BFD_RELOC_32);
495       gas_assert (rel->howto != NULL);
496     }
497 
498   return rel;
499 }
500