* Many files: Added gettext invocations around user-visible
[binutils-gdb.git] / gas / config / tc-i386.c
1 /* i386.c -- Assemble code for the Intel 80386
2 Copyright (C) 1989, 91, 92, 93, 94, 95, 96, 97, 1998
3 Free Software Foundation.
4
5 This file is part of GAS, the GNU Assembler.
6
7 GAS is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11
12 GAS is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GAS; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
21
22 /*
23 Intel 80386 machine specific gas.
24 Written by Eliot Dresselhaus (eliot@mgm.mit.edu).
25 Bugs & suggestions are completely welcome. This is free software.
26 Please help us make it better.
27 */
28
29 #include <ctype.h>
30
31 #include "as.h"
32 #include "subsegs.h"
33
34 #include "obstack.h"
35 #include "opcode/i386.h"
36
37 #ifndef TC_RELOC
38 #define TC_RELOC(X,Y) (Y)
39 #endif
40
41 static unsigned long mode_from_disp_size PARAMS ((unsigned long));
42 static int fits_in_signed_byte PARAMS ((long));
43 static int fits_in_unsigned_byte PARAMS ((long));
44 static int fits_in_unsigned_word PARAMS ((long));
45 static int fits_in_signed_word PARAMS ((long));
46 static int smallest_imm_type PARAMS ((long));
47 static int check_prefix PARAMS ((int));
48 static void set_16bit_code_flag PARAMS ((int));
49 #ifdef BFD_ASSEMBLER
50 static bfd_reloc_code_real_type reloc
51 PARAMS ((int, int, bfd_reloc_code_real_type));
52 #endif
53
54 /* 'md_assemble ()' gathers together information and puts it into a
55 i386_insn. */
56
57 struct _i386_insn
58 {
59 /* TM holds the template for the insn were currently assembling. */
60 template tm;
61 /* SUFFIX holds the opcode suffix (e.g. 'l' for 'movl') if given. */
62 char suffix;
63 /* Operands are coded with OPERANDS, TYPES, DISPS, IMMS, and REGS. */
64
65 /* OPERANDS gives the number of given operands. */
66 unsigned int operands;
67
68 /* REG_OPERANDS, DISP_OPERANDS, MEM_OPERANDS, IMM_OPERANDS give the number
69 of given register, displacement, memory operands and immediate
70 operands. */
71 unsigned int reg_operands, disp_operands, mem_operands, imm_operands;
72
73 /* TYPES [i] is the type (see above #defines) which tells us how to
74 search through DISPS [i] & IMMS [i] & REGS [i] for the required
75 operand. */
76 unsigned int types[MAX_OPERANDS];
77
78 /* Displacements (if given) for each operand. */
79 expressionS *disps[MAX_OPERANDS];
80
81 /* Relocation type for operand */
82 #ifdef BFD_ASSEMBLER
83 enum bfd_reloc_code_real disp_reloc[MAX_OPERANDS];
84 #else
85 int disp_reloc[MAX_OPERANDS];
86 #endif
87
88 /* Immediate operands (if given) for each operand. */
89 expressionS *imms[MAX_OPERANDS];
90
91 /* Register operands (if given) for each operand. */
92 reg_entry *regs[MAX_OPERANDS];
93
94 /* BASE_REG, INDEX_REG, and LOG2_SCALE_FACTOR are used to encode
95 the base index byte below. */
96 reg_entry *base_reg;
97 reg_entry *index_reg;
98 unsigned int log2_scale_factor;
99
100 /* SEG gives the seg_entries of this insn. They are zero unless
101 explicit segment overrides are given. */
102 const seg_entry *seg[2]; /* segments for memory operands (if given) */
103
104 /* PREFIX holds all the given prefix opcodes (usually null).
105 PREFIXES is the size of PREFIX. */
106 /* richfix: really unsigned? */
107 unsigned char prefix[MAX_PREFIXES];
108 unsigned int prefixes;
109
110 /* Wait prefix needs to come before any other prefixes, so handle
111 it specially. wait_prefix will hold the opcode modifier flag
112 FWait if a wait prefix is given. */
113 int wait_prefix;
114
115 /* RM and BI are the modrm byte and the base index byte where the
116 addressing modes of this insn are encoded. */
117
118 modrm_byte rm;
119 base_index_byte bi;
120 };
121
122 typedef struct _i386_insn i386_insn;
123
124 /* This array holds the chars that always start a comment. If the
125 pre-processor is disabled, these aren't very useful */
126 #if defined (TE_I386AIX) || defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
127 const char comment_chars[] = "#/";
128 #else
129 const char comment_chars[] = "#";
130 #endif
131
132 /* This array holds the chars that only start a comment at the beginning of
133 a line. If the line seems to have the form '# 123 filename'
134 .line and .file directives will appear in the pre-processed output */
135 /* Note that input_file.c hand checks for '#' at the beginning of the
136 first line of the input file. This is because the compiler outputs
137 #NO_APP at the beginning of its output. */
138 /* Also note that comments started like this one will always work if
139 '/' isn't otherwise defined. */
140 #if defined (TE_I386AIX) || defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
141 const char line_comment_chars[] = "";
142 #else
143 const char line_comment_chars[] = "/";
144 #endif
145 const char line_separator_chars[] = "";
146
147 /* Chars that can be used to separate mant from exp in floating point nums */
148 const char EXP_CHARS[] = "eE";
149
150 /* Chars that mean this number is a floating point constant */
151 /* As in 0f12.456 */
152 /* or 0d1.2345e12 */
153 const char FLT_CHARS[] = "fFdDxX";
154
155 /* tables for lexical analysis */
156 static char opcode_chars[256];
157 static char register_chars[256];
158 static char operand_chars[256];
159 static char space_chars[256];
160 static char identifier_chars[256];
161 static char digit_chars[256];
162
163 /* lexical macros */
164 #define is_opcode_char(x) (opcode_chars[(unsigned char) x])
165 #define is_operand_char(x) (operand_chars[(unsigned char) x])
166 #define is_register_char(x) (register_chars[(unsigned char) x])
167 #define is_space_char(x) (space_chars[(unsigned char) x])
168 #define is_identifier_char(x) (identifier_chars[(unsigned char) x])
169 #define is_digit_char(x) (digit_chars[(unsigned char) x])
170
171 /* put here all non-digit non-letter charcters that may occur in an operand */
172 static char operand_special_chars[] = "%$-+(,)*._~/<>|&^!:[@]";
173
174 /* md_assemble() always leaves the strings it's passed unaltered. To
175 effect this we maintain a stack of saved characters that we've smashed
176 with '\0's (indicating end of strings for various sub-fields of the
177 assembler instruction). */
178 static char save_stack[32];
179 static char *save_stack_p; /* stack pointer */
180 #define END_STRING_AND_SAVE(s) *save_stack_p++ = *s; *s = '\0'
181 #define RESTORE_END_STRING(s) *s = *--save_stack_p
182
183 /* The instruction we're assembling. */
184 static i386_insn i;
185
186 /* Possible templates for current insn. */
187 static templates *current_templates;
188
189 /* Per instruction expressionS buffers: 2 displacements & 2 immediate max. */
190 static expressionS disp_expressions[2], im_expressions[2];
191
192 /* Pointers to ebp & esp entries in reg_hash hash table. */
193 static reg_entry *ebp, *esp;
194
195 static int this_operand; /* current operand we are working on */
196
197 static int flag_do_long_jump; /* FIXME what does this do? */
198
199 static int flag_16bit_code; /* 1 if we're writing 16-bit code, 0 if 32-bit */
200
201 /* Interface to relax_segment.
202 There are 2 relax states for 386 jump insns: one for conditional &
203 one for unconditional jumps. This is because the these two types
204 of jumps add different sizes to frags when we're figuring out what
205 sort of jump to choose to reach a given label. */
206
207 /* types */
208 #define COND_JUMP 1 /* conditional jump */
209 #define UNCOND_JUMP 2 /* unconditional jump */
210 /* sizes */
211 #define BYTE 0
212 #define WORD 1
213 #define DWORD 2
214 #define UNKNOWN_SIZE 3
215
216 #ifndef INLINE
217 #ifdef __GNUC__
218 #define INLINE __inline__
219 #else
220 #define INLINE
221 #endif
222 #endif
223
224 #define ENCODE_RELAX_STATE(type,size) \
225 ((relax_substateT)((type<<2) | (size)))
226 #define SIZE_FROM_RELAX_STATE(s) \
227 ( (((s) & 0x3) == BYTE ? 1 : (((s) & 0x3) == WORD ? 2 : 4)) )
228
229 const relax_typeS md_relax_table[] =
230 {
231 /* The fields are:
232 1) most positive reach of this state,
233 2) most negative reach of this state,
234 3) how many bytes this mode will add to the size of the current frag
235 4) which index into the table to try if we can't fit into this one.
236 */
237 {1, 1, 0, 0},
238 {1, 1, 0, 0},
239 {1, 1, 0, 0},
240 {1, 1, 0, 0},
241
242 /* For now we don't use word displacement jumps; they will not work
243 for destination addresses > 0xFFFF, since they clear the upper 16
244 bits of %eip. */
245 {127 + 1, -128 + 1, 0, ENCODE_RELAX_STATE (COND_JUMP, DWORD)},
246 /* word conditionals add 3 bytes to frag:
247 2 opcode prefix; 1 displacement bytes */
248 {32767 + 2, -32768 + 2, 3, ENCODE_RELAX_STATE (COND_JUMP, DWORD)},
249 /* dword conditionals adds 4 bytes to frag:
250 1 opcode prefix; 3 displacement bytes */
251 {0, 0, 4, 0},
252 {1, 1, 0, 0},
253
254 {127 + 1, -128 + 1, 0, ENCODE_RELAX_STATE (UNCOND_JUMP, DWORD)},
255 /* word jmp adds 2 bytes to frag:
256 1 opcode prefix; 1 displacement bytes */
257 {32767 + 2, -32768 + 2, 2, ENCODE_RELAX_STATE (UNCOND_JUMP, DWORD)},
258 /* dword jmp adds 3 bytes to frag:
259 0 opcode prefix; 3 displacement bytes */
260 {0, 0, 3, 0},
261 {1, 1, 0, 0},
262
263 };
264
265
266 void
267 i386_align_code (fragP, count)
268 fragS *fragP;
269 int count;
270 {
271 /* Various efficient no-op patterns for aligning code labels. */
272 /* Note: Don't try to assemble the instructions in the comments. */
273 /* 0L and 0w are not legal */
274 static const char f32_1[] =
275 {0x90}; /* nop */
276 static const char f32_2[] =
277 {0x89,0xf6}; /* movl %esi,%esi */
278 static const char f32_3[] =
279 {0x8d,0x76,0x00}; /* leal 0(%esi),%esi */
280 static const char f32_4[] =
281 {0x8d,0x74,0x26,0x00}; /* leal 0(%esi,1),%esi */
282 static const char f32_5[] =
283 {0x90, /* nop */
284 0x8d,0x74,0x26,0x00}; /* leal 0(%esi,1),%esi */
285 static const char f32_6[] =
286 {0x8d,0xb6,0x00,0x00,0x00,0x00}; /* leal 0L(%esi),%esi */
287 static const char f32_7[] =
288 {0x8d,0xb4,0x26,0x00,0x00,0x00,0x00}; /* leal 0L(%esi,1),%esi */
289 static const char f32_8[] =
290 {0x90, /* nop */
291 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00}; /* leal 0L(%esi,1),%esi */
292 static const char f32_9[] =
293 {0x89,0xf6, /* movl %esi,%esi */
294 0x8d,0xbc,0x27,0x00,0x00,0x00,0x00}; /* leal 0L(%edi,1),%edi */
295 static const char f32_10[] =
296 {0x8d,0x76,0x00, /* leal 0(%esi),%esi */
297 0x8d,0xbc,0x27,0x00,0x00,0x00,0x00}; /* leal 0L(%edi,1),%edi */
298 static const char f32_11[] =
299 {0x8d,0x74,0x26,0x00, /* leal 0(%esi,1),%esi */
300 0x8d,0xbc,0x27,0x00,0x00,0x00,0x00}; /* leal 0L(%edi,1),%edi */
301 static const char f32_12[] =
302 {0x8d,0xb6,0x00,0x00,0x00,0x00, /* leal 0L(%esi),%esi */
303 0x8d,0xbf,0x00,0x00,0x00,0x00}; /* leal 0L(%edi),%edi */
304 static const char f32_13[] =
305 {0x8d,0xb6,0x00,0x00,0x00,0x00, /* leal 0L(%esi),%esi */
306 0x8d,0xbc,0x27,0x00,0x00,0x00,0x00}; /* leal 0L(%edi,1),%edi */
307 static const char f32_14[] =
308 {0x8d,0xb4,0x26,0x00,0x00,0x00,0x00, /* leal 0L(%esi,1),%esi */
309 0x8d,0xbc,0x27,0x00,0x00,0x00,0x00}; /* leal 0L(%edi,1),%edi */
310 static const char f32_15[] =
311 {0xeb,0x0d,0x90,0x90,0x90,0x90,0x90, /* jmp .+15; lotsa nops */
312 0x90,0x90,0x90,0x90,0x90,0x90,0x90,0x90};
313 static const char f16_4[] =
314 {0x8d,0xb4,0x00,0x00}; /* lea 0w(%si),%si */
315 static const char f16_5[] =
316 {0x90, /* nop */
317 0x8d,0xb4,0x00,0x00}; /* lea 0w(%si),%si */
318 static const char f16_6[] =
319 {0x89,0xf6, /* mov %si,%si */
320 0x8d,0xbd,0x00,0x00}; /* lea 0w(%di),%di */
321 static const char f16_7[] =
322 {0x8d,0x74,0x00, /* lea 0(%si),%si */
323 0x8d,0xbd,0x00,0x00}; /* lea 0w(%di),%di */
324 static const char f16_8[] =
325 {0x8d,0xb4,0x00,0x00, /* lea 0w(%si),%si */
326 0x8d,0xbd,0x00,0x00}; /* lea 0w(%di),%di */
327 static const char *const f32_patt[] = {
328 f32_1, f32_2, f32_3, f32_4, f32_5, f32_6, f32_7, f32_8,
329 f32_9, f32_10, f32_11, f32_12, f32_13, f32_14, f32_15
330 };
331 static const char *const f16_patt[] = {
332 f32_1, f32_2, f32_3, f16_4, f16_5, f16_6, f16_7, f16_8,
333 f32_15, f32_15, f32_15, f32_15, f32_15, f32_15, f32_15
334 };
335
336 if (count > 0 && count <= 15)
337 {
338 if (flag_16bit_code)
339 {
340 memcpy(fragP->fr_literal + fragP->fr_fix,
341 f16_patt[count - 1], count);
342 if (count > 8) /* adjust jump offset */
343 fragP->fr_literal[fragP->fr_fix + 1] = count - 2;
344 }
345 else
346 memcpy(fragP->fr_literal + fragP->fr_fix,
347 f32_patt[count - 1], count);
348 fragP->fr_var = count;
349 }
350 }
351
352 static char *output_invalid PARAMS ((int c));
353 static int i386_operand PARAMS ((char *operand_string));
354 static reg_entry *parse_register PARAMS ((char *reg_string));
355 #ifndef I386COFF
356 static void s_bss PARAMS ((int));
357 #endif
358
359 symbolS *GOT_symbol; /* Pre-defined "_GLOBAL_OFFSET_TABLE_" */
360
361 static INLINE unsigned long
362 mode_from_disp_size (t)
363 unsigned long t;
364 {
365 return (t & Disp8) ? 1 : (t & Disp32) ? 2 : 0;
366 }
367
368 #if 0
369 /* Not used. */
370 /* convert opcode suffix ('b' 'w' 'l' typically) into type specifier */
371
372 static INLINE unsigned long
373 opcode_suffix_to_type (s)
374 unsigned long s;
375 {
376 return (s == BYTE_OPCODE_SUFFIX
377 ? Byte : (s == WORD_OPCODE_SUFFIX
378 ? Word : DWord));
379 } /* opcode_suffix_to_type() */
380 #endif
381
382 static INLINE int
383 fits_in_signed_byte (num)
384 long num;
385 {
386 return (num >= -128) && (num <= 127);
387 } /* fits_in_signed_byte() */
388
389 static INLINE int
390 fits_in_unsigned_byte (num)
391 long num;
392 {
393 return (num & 0xff) == num;
394 } /* fits_in_unsigned_byte() */
395
396 static INLINE int
397 fits_in_unsigned_word (num)
398 long num;
399 {
400 return (num & 0xffff) == num;
401 } /* fits_in_unsigned_word() */
402
403 static INLINE int
404 fits_in_signed_word (num)
405 long num;
406 {
407 return (-32768 <= num) && (num <= 32767);
408 } /* fits_in_signed_word() */
409
410 static int
411 smallest_imm_type (num)
412 long num;
413 {
414 #if 0
415 /* This code is disabled because all the Imm1 forms in the opcode table
416 are slower on the i486, and they're the versions with the implicitly
417 specified single-position displacement, which has another syntax if
418 you really want to use that form. If you really prefer to have the
419 one-byte-shorter Imm1 form despite these problems, re-enable this
420 code. */
421 if (num == 1)
422 return Imm1 | Imm8 | Imm8S | Imm16 | Imm32;
423 #endif
424 return (fits_in_signed_byte (num)
425 ? (Imm8S | Imm8 | Imm16 | Imm32)
426 : fits_in_unsigned_byte (num)
427 ? (Imm8 | Imm16 | Imm32)
428 : (fits_in_signed_word (num) || fits_in_unsigned_word (num))
429 ? (Imm16 | Imm32)
430 : (Imm32));
431 } /* smallest_imm_type() */
432
433 static int
434 check_prefix (prefix)
435 int prefix;
436 {
437 int q;
438
439 for (q = 0; q < i.prefixes; q++)
440 {
441 switch (prefix)
442 {
443 case CS_PREFIX_OPCODE:
444 case DS_PREFIX_OPCODE:
445 case ES_PREFIX_OPCODE:
446 case FS_PREFIX_OPCODE:
447 case GS_PREFIX_OPCODE:
448 case SS_PREFIX_OPCODE:
449 switch (i.prefix[q])
450 {
451 case CS_PREFIX_OPCODE:
452 case DS_PREFIX_OPCODE:
453 case ES_PREFIX_OPCODE:
454 case FS_PREFIX_OPCODE:
455 case GS_PREFIX_OPCODE:
456 case SS_PREFIX_OPCODE:
457 as_bad ("same type of prefix used twice");
458 return 0;
459 }
460 break;
461
462 case REPNE:
463 case REPE:
464 switch (i.prefix[q])
465 {
466 case REPNE:
467 case REPE:
468 as_bad ("same type of prefix used twice");
469 return 0;
470 }
471 break;
472
473 case FWAIT_OPCODE:
474 if (i.wait_prefix != 0)
475 {
476 as_bad ("same type of prefix used twice");
477 return 0;
478 }
479 break;
480
481 default:
482 if (i.prefix[q] == prefix)
483 {
484 as_bad ("same type of prefix used twice");
485 return 0;
486 }
487 }
488 }
489
490 if (i.prefixes == MAX_PREFIXES && prefix != FWAIT_OPCODE)
491 {
492 char *p = "another"; /* paranoia */
493
494 for (q = 0;
495 q < sizeof (i386_prefixtab) / sizeof (i386_prefixtab[0]);
496 q++)
497 if (i386_prefixtab[q].prefix_code == prefix)
498 p = i386_prefixtab[q].prefix_name;
499
500 as_bad ("%d prefixes given and `%%%s' prefix gives too many",
501 MAX_PREFIXES, p);
502 return 0;
503 }
504
505 return 1;
506 }
507
508 static void
509 set_16bit_code_flag (new_16bit_code_flag)
510 int new_16bit_code_flag;
511 {
512 flag_16bit_code = new_16bit_code_flag;
513 }
514
515 const pseudo_typeS md_pseudo_table[] =
516 {
517 #ifndef I386COFF
518 {"bss", s_bss, 0},
519 #endif
520 #if !defined(OBJ_AOUT) && !defined(USE_ALIGN_PTWO)
521 {"align", s_align_bytes, 0},
522 #else
523 {"align", s_align_ptwo, 0},
524 #endif
525 {"ffloat", float_cons, 'f'},
526 {"dfloat", float_cons, 'd'},
527 {"tfloat", float_cons, 'x'},
528 {"value", cons, 2},
529 {"noopt", s_ignore, 0},
530 {"optim", s_ignore, 0},
531 {"code16", set_16bit_code_flag, 1},
532 {"code32", set_16bit_code_flag, 0},
533 {0, 0, 0}
534 };
535
536 /* for interface with expression () */
537 extern char *input_line_pointer;
538
539 /* obstack for constructing various things in md_begin */
540 struct obstack o;
541
542 /* hash table for opcode lookup */
543 static struct hash_control *op_hash;
544 /* hash table for register lookup */
545 static struct hash_control *reg_hash;
546 /* hash table for prefix lookup */
547 static struct hash_control *prefix_hash;
548 \f
549
550 void
551 md_begin ()
552 {
553 const char *hash_err;
554
555 obstack_begin (&o, 4096);
556
557 /* initialize op_hash hash table */
558 op_hash = hash_new ();
559
560 {
561 register const template *optab;
562 register templates *core_optab;
563 char *prev_name;
564
565 optab = i386_optab; /* setup for loop */
566 prev_name = optab->name;
567 obstack_grow (&o, optab, sizeof (template));
568 core_optab = (templates *) xmalloc (sizeof (templates));
569
570 for (optab++; optab < i386_optab_end; optab++)
571 {
572 if (!strcmp (optab->name, prev_name))
573 {
574 /* same name as before --> append to current template list */
575 obstack_grow (&o, optab, sizeof (template));
576 }
577 else
578 {
579 /* different name --> ship out current template list;
580 add to hash table; & begin anew */
581 /* Note: end must be set before start! since obstack_next_free
582 changes upon opstack_finish */
583 core_optab->end = (template *) obstack_next_free (&o);
584 core_optab->start = (template *) obstack_finish (&o);
585 hash_err = hash_insert (op_hash, prev_name, (char *) core_optab);
586 if (hash_err)
587 {
588 hash_error:
589 as_fatal (_("Internal Error: Can't hash %s: %s"), prev_name,
590 hash_err);
591 }
592 prev_name = optab->name;
593 core_optab = (templates *) xmalloc (sizeof (templates));
594 obstack_grow (&o, optab, sizeof (template));
595 }
596 }
597 }
598
599 /* initialize reg_hash hash table */
600 reg_hash = hash_new ();
601 {
602 register const reg_entry *regtab;
603
604 for (regtab = i386_regtab; regtab < i386_regtab_end; regtab++)
605 {
606 hash_err = hash_insert (reg_hash, regtab->reg_name, (PTR) regtab);
607 if (hash_err)
608 goto hash_error;
609 }
610 }
611
612 esp = (reg_entry *) hash_find (reg_hash, "esp");
613 ebp = (reg_entry *) hash_find (reg_hash, "ebp");
614
615 /* initialize reg_hash hash table */
616 prefix_hash = hash_new ();
617 {
618 register const prefix_entry *prefixtab;
619
620 for (prefixtab = i386_prefixtab;
621 prefixtab < i386_prefixtab_end; prefixtab++)
622 {
623 hash_err = hash_insert (prefix_hash, prefixtab->prefix_name,
624 (PTR) prefixtab);
625 if (hash_err)
626 goto hash_error;
627 }
628 }
629
630 /* fill in lexical tables: opcode_chars, operand_chars, space_chars */
631 {
632 register int c;
633 register char *p;
634
635 for (c = 0; c < 256; c++)
636 {
637 if (islower (c) || isdigit (c))
638 {
639 opcode_chars[c] = c;
640 register_chars[c] = c;
641 }
642 else if (isupper (c))
643 {
644 opcode_chars[c] = tolower (c);
645 register_chars[c] = opcode_chars[c];
646 }
647 else if (c == PREFIX_SEPERATOR)
648 {
649 opcode_chars[c] = c;
650 }
651 else if (c == ')' || c == '(')
652 {
653 register_chars[c] = c;
654 }
655
656 if (isupper (c) || islower (c) || isdigit (c))
657 operand_chars[c] = c;
658
659 if (isdigit (c) || c == '-')
660 digit_chars[c] = c;
661
662 if (isalpha (c) || c == '_' || c == '.' || isdigit (c))
663 identifier_chars[c] = c;
664
665 #ifdef LEX_AT
666 identifier_chars['@'] = '@';
667 #endif
668
669 if (c == ' ' || c == '\t')
670 space_chars[c] = c;
671 }
672
673 for (p = operand_special_chars; *p != '\0'; p++)
674 operand_chars[(unsigned char) *p] = *p;
675 }
676
677 #if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
678 if (OUTPUT_FLAVOR == bfd_target_elf_flavour)
679 {
680 record_alignment (text_section, 2);
681 record_alignment (data_section, 2);
682 record_alignment (bss_section, 2);
683 }
684 #endif
685 }
686
687 void
688 i386_print_statistics (file)
689 FILE *file;
690 {
691 hash_print_statistics (file, "i386 opcode", op_hash);
692 hash_print_statistics (file, "i386 register", reg_hash);
693 hash_print_statistics (file, "i386 prefix", prefix_hash);
694 }
695 \f
696
697 #ifdef DEBUG386
698
699 /* debugging routines for md_assemble */
700 static void pi PARAMS ((char *, i386_insn *));
701 static void pte PARAMS ((template *));
702 static void pt PARAMS ((unsigned int));
703 static void pe PARAMS ((expressionS *));
704 static void ps PARAMS ((symbolS *));
705
706 static void
707 pi (line, x)
708 char *line;
709 i386_insn *x;
710 {
711 register template *p;
712 int i;
713
714 fprintf (stdout, "%s: template ", line);
715 pte (&x->tm);
716 fprintf (stdout, " modrm: mode %x reg %x reg/mem %x",
717 x->rm.mode, x->rm.reg, x->rm.regmem);
718 fprintf (stdout, " base %x index %x scale %x\n",
719 x->bi.base, x->bi.index, x->bi.scale);
720 for (i = 0; i < x->operands; i++)
721 {
722 fprintf (stdout, " #%d: ", i + 1);
723 pt (x->types[i]);
724 fprintf (stdout, "\n");
725 if (x->types[i]
726 & (Reg | SReg2 | SReg3 | Control | Debug | Test | RegMMX))
727 fprintf (stdout, "%s\n", x->regs[i]->reg_name);
728 if (x->types[i] & Imm)
729 pe (x->imms[i]);
730 if (x->types[i] & (Disp | Abs))
731 pe (x->disps[i]);
732 }
733 }
734
735 static void
736 pte (t)
737 template *t;
738 {
739 int i;
740 fprintf (stdout, " %d operands ", t->operands);
741 fprintf (stdout, "opcode %x ",
742 t->base_opcode);
743 if (t->extension_opcode != None)
744 fprintf (stdout, "ext %x ", t->extension_opcode);
745 if (t->opcode_modifier & D)
746 fprintf (stdout, "D");
747 if (t->opcode_modifier & W)
748 fprintf (stdout, "W");
749 fprintf (stdout, "\n");
750 for (i = 0; i < t->operands; i++)
751 {
752 fprintf (stdout, " #%d type ", i + 1);
753 pt (t->operand_types[i]);
754 fprintf (stdout, "\n");
755 }
756 }
757
758 static void
759 pe (e)
760 expressionS *e;
761 {
762 fprintf (stdout, " operation %d\n", e->X_op);
763 fprintf (stdout, " add_number %d (%x)\n",
764 e->X_add_number, e->X_add_number);
765 if (e->X_add_symbol)
766 {
767 fprintf (stdout, " add_symbol ");
768 ps (e->X_add_symbol);
769 fprintf (stdout, "\n");
770 }
771 if (e->X_op_symbol)
772 {
773 fprintf (stdout, " op_symbol ");
774 ps (e->X_op_symbol);
775 fprintf (stdout, "\n");
776 }
777 }
778
779 static void
780 ps (s)
781 symbolS *s;
782 {
783 fprintf (stdout, "%s type %s%s",
784 S_GET_NAME (s),
785 S_IS_EXTERNAL (s) ? "EXTERNAL " : "",
786 segment_name (S_GET_SEGMENT (s)));
787 }
788
789 struct type_name
790 {
791 unsigned int mask;
792 char *tname;
793 }
794
795 type_names[] =
796 {
797 { Reg8, "r8" },
798 { Reg16, "r16" },
799 { Reg32, "r32" },
800 { Imm8, "i8" },
801 { Imm8S, "i8s" },
802 { Imm16, "i16" },
803 { Imm32, "i32" },
804 { Mem8, "Mem8" },
805 { Mem16, "Mem16" },
806 { Mem32, "Mem32" },
807 { BaseIndex, "BaseIndex" },
808 { Abs8, "Abs8" },
809 { Abs16, "Abs16" },
810 { Abs32, "Abs32" },
811 { Disp8, "d8" },
812 { Disp16, "d16" },
813 { Disp32, "d32" },
814 { SReg2, "SReg2" },
815 { SReg3, "SReg3" },
816 { Acc, "Acc" },
817 { InOutPortReg, "InOutPortReg" },
818 { ShiftCount, "ShiftCount" },
819 { Imm1, "i1" },
820 { Control, "control reg" },
821 { Test, "test reg" },
822 { Debug, "debug reg" },
823 { FloatReg, "FReg" },
824 { FloatAcc, "FAcc" },
825 { JumpAbsolute, "Jump Absolute" },
826 { RegMMX, "rMMX" },
827 { EsSeg, "es" },
828 { 0, "" }
829 };
830
831 static void
832 pt (t)
833 unsigned int t;
834 {
835 register struct type_name *ty;
836
837 if (t == Unknown)
838 {
839 fprintf (stdout, _("Unknown"));
840 }
841 else
842 {
843 for (ty = type_names; ty->mask; ty++)
844 if (t & ty->mask)
845 fprintf (stdout, "%s, ", ty->tname);
846 }
847 fflush (stdout);
848 }
849
850 #endif /* DEBUG386 */
851 \f
852 #ifdef BFD_ASSEMBLER
853 static bfd_reloc_code_real_type
854 reloc (size, pcrel, other)
855 int size;
856 int pcrel;
857 bfd_reloc_code_real_type other;
858 {
859 if (other != NO_RELOC) return other;
860
861 if (pcrel)
862 switch (size)
863 {
864 case 1: return BFD_RELOC_8_PCREL;
865 case 2: return BFD_RELOC_16_PCREL;
866 case 4: return BFD_RELOC_32_PCREL;
867 }
868 else
869 switch (size)
870 {
871 case 1: return BFD_RELOC_8;
872 case 2: return BFD_RELOC_16;
873 case 4: return BFD_RELOC_32;
874 }
875
876 if (pcrel)
877 as_bad (_("Can not do %d byte pc-relative relocation"), size);
878 else
879 as_bad (_("Can not do %d byte relocation"), size);
880
881 return BFD_RELOC_NONE;
882 }
883
884 /*
885 * Here we decide which fixups can be adjusted to make them relative to
886 * the beginning of the section instead of the symbol. Basically we need
887 * to make sure that the dynamic relocations are done correctly, so in
888 * some cases we force the original symbol to be used.
889 */
890 int
891 tc_i386_fix_adjustable(fixP)
892 fixS * fixP;
893 {
894 #ifdef OBJ_ELF
895 /* Prevent all adjustments to global symbols. */
896 if (S_IS_EXTERN (fixP->fx_addsy))
897 return 0;
898 if (S_IS_WEAK (fixP->fx_addsy))
899 return 0;
900 #endif /* ! defined (OBJ_AOUT) */
901 /* adjust_reloc_syms doesn't know about the GOT */
902 if (fixP->fx_r_type == BFD_RELOC_386_GOTOFF
903 || fixP->fx_r_type == BFD_RELOC_386_PLT32
904 || fixP->fx_r_type == BFD_RELOC_386_GOT32)
905 return 0;
906 return 1;
907 }
908 #else
909 #define reloc(SIZE,PCREL,OTHER) 0
910 #define BFD_RELOC_32 0
911 #define BFD_RELOC_32_PCREL 0
912 #define BFD_RELOC_386_PLT32 0
913 #define BFD_RELOC_386_GOT32 0
914 #define BFD_RELOC_386_GOTOFF 0
915 #endif
916
917 /* This is the guts of the machine-dependent assembler. LINE points to a
918 machine dependent instruction. This function is supposed to emit
919 the frags/bytes it assembles to. */
920
921 void
922 md_assemble (line)
923 char *line;
924 {
925 /* Points to template once we've found it. */
926 const template *t;
927
928 /* Count the size of the instruction generated. */
929 int insn_size = 0;
930
931 int j;
932
933 /* Initialize globals. */
934 memset (&i, '\0', sizeof (i));
935 for (j = 0; j < MAX_OPERANDS; j++)
936 i.disp_reloc[j] = NO_RELOC;
937 memset (disp_expressions, '\0', sizeof (disp_expressions));
938 memset (im_expressions, '\0', sizeof (im_expressions));
939 save_stack_p = save_stack; /* reset stack pointer */
940
941 /* First parse an opcode & call i386_operand for the operands.
942 We assume that the scrubber has arranged it so that line[0] is the valid
943 start of a (possibly prefixed) opcode. */
944 {
945 char *l = line;
946
947 /* 1 if operand is pending after ','. */
948 unsigned int expecting_operand = 0;
949 /* Non-zero if we found a prefix only acceptable with string insns. */
950 const char *expecting_string_instruction = NULL;
951 /* Non-zero if operand parens not balanced. */
952 unsigned int paren_not_balanced;
953 char *token_start = l;
954
955 while (!is_space_char (*l) && *l != END_OF_INSN)
956 {
957 if (!is_opcode_char (*l))
958 {
959 as_bad (_("invalid character %s in opcode"), output_invalid (*l));
960 return;
961 }
962 else if (*l != PREFIX_SEPERATOR)
963 {
964 *l = opcode_chars[(unsigned char) *l]; /* fold case of opcodes */
965 l++;
966 }
967 else
968 {
969 /* This opcode's got a prefix. */
970 unsigned int q;
971 prefix_entry *prefix;
972
973 if (l == token_start)
974 {
975 as_bad (_("expecting prefix; got nothing"));
976 return;
977 }
978 END_STRING_AND_SAVE (l);
979 prefix = (prefix_entry *) hash_find (prefix_hash, token_start);
980 if (!prefix)
981 {
982 as_bad (_("no such opcode prefix `%s'"), token_start);
983 RESTORE_END_STRING (l);
984 return;
985 }
986 RESTORE_END_STRING (l);
987 /* check for repeated prefix */
988 if (! check_prefix (prefix->prefix_code))
989 return;
990 if (prefix->prefix_code == FWAIT_OPCODE)
991 {
992 i.wait_prefix = FWait;
993 }
994 else
995 {
996 i.prefix[i.prefixes++] = prefix->prefix_code;
997 if (prefix->prefix_code == REPE
998 || prefix->prefix_code == REPNE)
999 expecting_string_instruction = prefix->prefix_name;
1000 }
1001 /* Skip past PREFIX_SEPARATOR and reset token_start. */
1002 token_start = ++l;
1003 }
1004 }
1005 END_STRING_AND_SAVE (l);
1006 if (token_start == l)
1007 {
1008 as_bad (_("expecting opcode; got nothing"));
1009 RESTORE_END_STRING (l);
1010 return;
1011 }
1012
1013 /* Lookup insn in hash; try intel & att naming conventions if appropriate;
1014 that is: we only use the opcode suffix 'b' 'w' or 'l' if we need to. */
1015 current_templates = (templates *) hash_find (op_hash, token_start);
1016 if (!current_templates)
1017 {
1018 int last_index = strlen (token_start) - 1;
1019 char last_char = token_start[last_index];
1020 switch (last_char)
1021 {
1022 case DWORD_OPCODE_SUFFIX:
1023 case WORD_OPCODE_SUFFIX:
1024 case BYTE_OPCODE_SUFFIX:
1025 token_start[last_index] = '\0';
1026 current_templates = (templates *) hash_find (op_hash, token_start);
1027 token_start[last_index] = last_char;
1028 i.suffix = last_char;
1029 }
1030 if (!current_templates)
1031 {
1032 as_bad (_("no such 386 instruction: `%s'"), token_start);
1033 RESTORE_END_STRING (l);
1034 return;
1035 }
1036 }
1037 RESTORE_END_STRING (l);
1038
1039 /* check for rep/repne without a string instruction */
1040 if (expecting_string_instruction &&
1041 !(current_templates->start->opcode_modifier & IsString))
1042 {
1043 as_bad (_("expecting string instruction after `%s'"),
1044 expecting_string_instruction);
1045 return;
1046 }
1047
1048 /* There may be operands to parse. */
1049 if (*l != END_OF_INSN)
1050 {
1051 /* parse operands */
1052 do
1053 {
1054 /* skip optional white space before operand */
1055 while (!is_operand_char (*l) && *l != END_OF_INSN)
1056 {
1057 if (!is_space_char (*l))
1058 {
1059 as_bad (_("invalid character %s before operand %d"),
1060 output_invalid (*l), i.operands);
1061 return;
1062 }
1063 l++;
1064 }
1065 token_start = l; /* after white space */
1066 paren_not_balanced = 0;
1067 while (paren_not_balanced || *l != ',')
1068 {
1069 if (*l == END_OF_INSN)
1070 {
1071 if (paren_not_balanced)
1072 {
1073 as_bad (_("unbalanced parenthesis in operand %d."),
1074 i.operands);
1075 return;
1076 }
1077 else
1078 break; /* we are done */
1079 }
1080 else if (!is_operand_char (*l) && !is_space_char (*l))
1081 {
1082 as_bad (_("invalid character %s in operand %d"),
1083 output_invalid (*l), i.operands);
1084 return;
1085 }
1086 if (*l == '(')
1087 ++paren_not_balanced;
1088 if (*l == ')')
1089 --paren_not_balanced;
1090 l++;
1091 }
1092 if (l != token_start)
1093 { /* yes, we've read in another operand */
1094 unsigned int operand_ok;
1095 this_operand = i.operands++;
1096 if (i.operands > MAX_OPERANDS)
1097 {
1098 as_bad (_("spurious operands; (%d operands/instruction max)"),
1099 MAX_OPERANDS);
1100 return;
1101 }
1102 /* now parse operand adding info to 'i' as we go along */
1103 END_STRING_AND_SAVE (l);
1104 operand_ok = i386_operand (token_start);
1105 RESTORE_END_STRING (l); /* restore old contents */
1106 if (!operand_ok)
1107 return;
1108 }
1109 else
1110 {
1111 if (expecting_operand)
1112 {
1113 expecting_operand_after_comma:
1114 as_bad (_("expecting operand after ','; got nothing"));
1115 return;
1116 }
1117 if (*l == ',')
1118 {
1119 as_bad (_("expecting operand before ','; got nothing"));
1120 return;
1121 }
1122 }
1123
1124 /* now *l must be either ',' or END_OF_INSN */
1125 if (*l == ',')
1126 {
1127 if (*++l == END_OF_INSN)
1128 { /* just skip it, if it's \n complain */
1129 goto expecting_operand_after_comma;
1130 }
1131 expecting_operand = 1;
1132 }
1133 }
1134 while (*l != END_OF_INSN); /* until we get end of insn */
1135 }
1136 }
1137
1138 /* Now we've parsed the opcode into a set of templates, and have the
1139 operands at hand.
1140
1141 Next, we find a template that matches the given insn,
1142 making sure the overlap of the given operands types is consistent
1143 with the template operand types. */
1144
1145 #define MATCH(overlap,given_type) \
1146 (overlap && \
1147 (((overlap & (JumpAbsolute|BaseIndex|Mem8)) \
1148 == (given_type & (JumpAbsolute|BaseIndex|Mem8))) \
1149 || (overlap == InOutPortReg)))
1150
1151
1152 /* If m0 and m1 are register matches they must be consistent
1153 with the expected operand types t0 and t1.
1154 That is, if both m0 & m1 are register matches
1155 i.e. ( ((m0 & (Reg)) && (m1 & (Reg)) ) ?
1156 then, either 1. or 2. must be true:
1157 1. the expected operand type register overlap is null:
1158 (t0 & t1 & Reg) == 0
1159 AND
1160 the given register overlap is null:
1161 (m0 & m1 & Reg) == 0
1162 2. the expected operand type register overlap == the given
1163 operand type overlap: (t0 & t1 & m0 & m1 & Reg).
1164 */
1165 #define CONSISTENT_REGISTER_MATCH(m0, m1, t0, t1) \
1166 ( ((m0 & (Reg)) && (m1 & (Reg))) ? \
1167 ( ((t0 & t1 & (Reg)) == 0 && (m0 & m1 & (Reg)) == 0) || \
1168 ((t0 & t1) & (m0 & m1) & (Reg)) \
1169 ) : 1)
1170 {
1171 register unsigned int overlap0, overlap1;
1172 expressionS *exp;
1173 unsigned int overlap2;
1174 unsigned int found_reverse_match;
1175
1176 overlap0 = overlap1 = overlap2 = found_reverse_match = 0;
1177 for (t = current_templates->start;
1178 t < current_templates->end;
1179 t++)
1180 {
1181 /* must have right number of operands */
1182 if (i.operands != t->operands)
1183 continue;
1184 else if (!t->operands)
1185 break; /* 0 operands always matches */
1186
1187 overlap0 = i.types[0] & t->operand_types[0];
1188 switch (t->operands)
1189 {
1190 case 1:
1191 if (!MATCH (overlap0, i.types[0]))
1192 continue;
1193 break;
1194 case 2:
1195 case 3:
1196 overlap1 = i.types[1] & t->operand_types[1];
1197 if (!MATCH (overlap0, i.types[0]) ||
1198 !MATCH (overlap1, i.types[1]) ||
1199 !CONSISTENT_REGISTER_MATCH (overlap0, overlap1,
1200 t->operand_types[0],
1201 t->operand_types[1]))
1202 {
1203
1204 /* check if other direction is valid ... */
1205 if (!(t->opcode_modifier & COMES_IN_BOTH_DIRECTIONS))
1206 continue;
1207
1208 /* try reversing direction of operands */
1209 overlap0 = i.types[0] & t->operand_types[1];
1210 overlap1 = i.types[1] & t->operand_types[0];
1211 if (!MATCH (overlap0, i.types[0]) ||
1212 !MATCH (overlap1, i.types[1]) ||
1213 !CONSISTENT_REGISTER_MATCH (overlap0, overlap1,
1214 t->operand_types[1],
1215 t->operand_types[0]))
1216 {
1217 /* does not match either direction */
1218 continue;
1219 }
1220 /* found a reverse match here -- slip through */
1221 /* found_reverse_match holds which of D or FloatD we've found */
1222 found_reverse_match = t->opcode_modifier & COMES_IN_BOTH_DIRECTIONS;
1223 } /* endif: not forward match */
1224 /* found either forward/reverse 2 operand match here */
1225 if (t->operands == 3)
1226 {
1227 overlap2 = i.types[2] & t->operand_types[2];
1228 if (!MATCH (overlap2, i.types[2]) ||
1229 !CONSISTENT_REGISTER_MATCH (overlap0, overlap2,
1230 t->operand_types[0],
1231 t->operand_types[2]) ||
1232 !CONSISTENT_REGISTER_MATCH (overlap1, overlap2,
1233 t->operand_types[1],
1234 t->operand_types[2]))
1235 continue;
1236 }
1237 /* found either forward/reverse 2 or 3 operand match here:
1238 slip through to break */
1239 }
1240 break; /* we've found a match; break out of loop */
1241 } /* for (t = ... */
1242 if (t == current_templates->end)
1243 { /* we found no match */
1244 as_bad (_("suffix or operands invalid for `%s'"),
1245 current_templates->start->name);
1246 return;
1247 }
1248
1249 /* Copy the template we found. */
1250 i.tm = *t;
1251 i.tm.opcode_modifier |= i.wait_prefix;
1252
1253 if (found_reverse_match)
1254 {
1255 i.tm.operand_types[0] = t->operand_types[1];
1256 i.tm.operand_types[1] = t->operand_types[0];
1257 }
1258
1259 /* Check string instruction segment overrides */
1260 if ((i.tm.opcode_modifier & IsString) != 0 && i.mem_operands != 0)
1261 {
1262 int mem_op = (i.types[0] & Mem) ? 0 : 1;
1263 if ((i.tm.operand_types[mem_op+0] & EsSeg) != 0)
1264 {
1265 if (i.seg[0] != (seg_entry *) 0 && i.seg[0] != (seg_entry *) &es)
1266 {
1267 as_bad ("`%s' %s operand must use `%%es' segment",
1268 i.tm.name,
1269 ordinal_names[mem_op+0]);
1270 return;
1271 }
1272 /* There's only ever one segment override allowed per instruction.
1273 This instruction possibly has a legal segment override on the
1274 second operand, so copy the segment to where non-string
1275 instructions store it, allowing common code. */
1276 i.seg[0] = i.seg[1];
1277 }
1278 else if ((i.tm.operand_types[mem_op+1] & EsSeg) != 0)
1279 {
1280 if (i.seg[1] != (seg_entry *) 0 && i.seg[1] != (seg_entry *) &es)
1281 {
1282 as_bad ("`%s' %s operand must use `%%es' segment",
1283 i.tm.name,
1284 ordinal_names[mem_op+1]);
1285 return;
1286 }
1287 }
1288 }
1289
1290 /* If the matched instruction specifies an explicit opcode suffix,
1291 use it - and make sure none has already been specified. */
1292 if (i.tm.opcode_modifier & (Data16|Data32))
1293 {
1294 if (i.suffix)
1295 {
1296 as_bad (_("extraneous opcode suffix given"));
1297 return;
1298 }
1299 if (i.tm.opcode_modifier & Data16)
1300 i.suffix = WORD_OPCODE_SUFFIX;
1301 else
1302 i.suffix = DWORD_OPCODE_SUFFIX;
1303 }
1304
1305 /* If there's no opcode suffix we try to invent one based on register
1306 operands. */
1307 if (!i.suffix && i.reg_operands)
1308 {
1309 /* We take i.suffix from the LAST register operand specified. This
1310 assumes that the last register operands is the destination register
1311 operand. */
1312 int op;
1313 for (op = 0; op < MAX_OPERANDS; op++)
1314 if (i.types[op] & Reg)
1315 {
1316 i.suffix = ((i.types[op] & Reg8) ? BYTE_OPCODE_SUFFIX :
1317 (i.types[op] & Reg16) ? WORD_OPCODE_SUFFIX :
1318 DWORD_OPCODE_SUFFIX);
1319 }
1320 }
1321 else if (i.suffix != 0
1322 && i.reg_operands != 0
1323 && (i.types[i.operands - 1] & Reg) != 0)
1324 {
1325 int bad;
1326
1327 /* If the last operand is a register, make sure it is
1328 compatible with the suffix. */
1329
1330 bad = 0;
1331 switch (i.suffix)
1332 {
1333 default:
1334 abort ();
1335 case BYTE_OPCODE_SUFFIX:
1336 /* If this is an eight bit register, it's OK. If it's the
1337 16 or 32 bit version of an eight bit register, we will
1338 just use the low portion, and that's OK too. */
1339 if ((i.types[i.operands - 1] & Reg8) == 0
1340 && i.regs[i.operands - 1]->reg_num >= 4)
1341 bad = 1;
1342 break;
1343 case WORD_OPCODE_SUFFIX:
1344 case DWORD_OPCODE_SUFFIX:
1345 /* We don't insist on the presence or absence of the e
1346 prefix on the register, but we reject eight bit
1347 registers. */
1348 if ((i.types[i.operands - 1] & Reg8) != 0)
1349 bad = 1;
1350 }
1351 if (bad)
1352 as_bad (_("register does not match opcode suffix"));
1353 }
1354
1355 /* Make still unresolved immediate matches conform to size of immediate
1356 given in i.suffix. Note: overlap2 cannot be an immediate!
1357 We assume this. */
1358 if ((overlap0 & (Imm8 | Imm8S | Imm16 | Imm32))
1359 && overlap0 != Imm8 && overlap0 != Imm8S
1360 && overlap0 != Imm16 && overlap0 != Imm32)
1361 {
1362 if (!i.suffix)
1363 {
1364 as_bad (_("no opcode suffix given; can't determine immediate size"));
1365 return;
1366 }
1367 overlap0 &= (i.suffix == BYTE_OPCODE_SUFFIX ? (Imm8 | Imm8S) :
1368 (i.suffix == WORD_OPCODE_SUFFIX ? Imm16 : Imm32));
1369 }
1370 if ((overlap1 & (Imm8 | Imm8S | Imm16 | Imm32))
1371 && overlap1 != Imm8 && overlap1 != Imm8S
1372 && overlap1 != Imm16 && overlap1 != Imm32)
1373 {
1374 if (!i.suffix)
1375 {
1376 as_bad (_("no opcode suffix given; can't determine immediate size"));
1377 return;
1378 }
1379 overlap1 &= (i.suffix == BYTE_OPCODE_SUFFIX ? (Imm8 | Imm8S) :
1380 (i.suffix == WORD_OPCODE_SUFFIX ? Imm16 : Imm32));
1381 }
1382
1383 i.types[0] = overlap0;
1384 i.types[1] = overlap1;
1385 i.types[2] = overlap2;
1386
1387 if (overlap0 & ImplicitRegister)
1388 i.reg_operands--;
1389 if (overlap1 & ImplicitRegister)
1390 i.reg_operands--;
1391 if (overlap2 & ImplicitRegister)
1392 i.reg_operands--;
1393 if (overlap0 & Imm1)
1394 i.imm_operands = 0; /* kludge for shift insns */
1395
1396 /* Finalize opcode. First, we change the opcode based on the operand
1397 size given by i.suffix: we never have to change things for byte insns,
1398 or when no opcode suffix is need to size the operands. */
1399
1400 if (!i.suffix && (i.tm.opcode_modifier & W))
1401 {
1402 as_bad (_("no opcode suffix given and no register operands; can't size instruction"));
1403 return;
1404 }
1405
1406 if (i.suffix && i.suffix != BYTE_OPCODE_SUFFIX)
1407 {
1408 /* Select between byte and word/dword operations. */
1409 if (i.tm.opcode_modifier & W)
1410 i.tm.base_opcode |= W;
1411 /* Now select between word & dword operations via the
1412 operand size prefix. */
1413 if ((i.suffix == WORD_OPCODE_SUFFIX) ^ flag_16bit_code)
1414 {
1415 if (! check_prefix (WORD_PREFIX_OPCODE))
1416 return;
1417 i.prefix[i.prefixes++] = WORD_PREFIX_OPCODE;
1418 }
1419 }
1420
1421 /* For insns with operands there are more diddles to do to the opcode. */
1422 if (i.operands)
1423 {
1424 /* Default segment register this instruction will use
1425 for memory accesses. 0 means unknown.
1426 This is only for optimizing out unnecessary segment overrides. */
1427 const seg_entry *default_seg = 0;
1428
1429 /* True if this instruction uses a memory addressing mode,
1430 and therefore may need an address-size prefix. */
1431 int uses_mem_addrmode = 0;
1432
1433
1434 /* If we found a reverse match we must alter the opcode direction bit
1435 found_reverse_match holds bit to set (different for int &
1436 float insns). */
1437
1438 i.tm.base_opcode ^= found_reverse_match;
1439
1440 /* The imul $imm, %reg instruction is converted into
1441 imul $imm, %reg, %reg, and the clr %reg instruction
1442 is converted into xor %reg, %reg. */
1443 if (i.tm.opcode_modifier & regKludge)
1444 {
1445 unsigned int first_reg_op = (i.types[0] & Reg) ? 0 : 1;
1446 /* Pretend we saw the extra register operand. */
1447 i.regs[first_reg_op+1] = i.regs[first_reg_op];
1448 i.reg_operands = 2;
1449 }
1450
1451 if (i.tm.opcode_modifier & ShortForm)
1452 {
1453 /* The register or float register operand is in operand 0 or 1. */
1454 unsigned int op = (i.types[0] & (Reg | FloatReg)) ? 0 : 1;
1455 /* Register goes in low 3 bits of opcode. */
1456 i.tm.base_opcode |= i.regs[op]->reg_num;
1457 }
1458 else if (i.tm.opcode_modifier & ShortFormW)
1459 {
1460 /* Short form with 0x8 width bit. Register is always dest. operand */
1461 i.tm.base_opcode |= i.regs[1]->reg_num;
1462 if (i.suffix == WORD_OPCODE_SUFFIX ||
1463 i.suffix == DWORD_OPCODE_SUFFIX)
1464 i.tm.base_opcode |= 0x8;
1465 }
1466 else if (i.tm.opcode_modifier & Modrm)
1467 {
1468 /* The opcode is completed (modulo i.tm.extension_opcode which
1469 must be put into the modrm byte).
1470 Now, we make the modrm & index base bytes based on all the
1471 info we've collected. */
1472
1473 /* i.reg_operands MUST be the number of real register operands;
1474 implicit registers do not count. */
1475 if (i.reg_operands == 2)
1476 {
1477 unsigned int source, dest;
1478 source = ((i.types[0]
1479 & (Reg
1480 | SReg2
1481 | SReg3
1482 | Control
1483 | Debug
1484 | Test
1485 | RegMMX))
1486 ? 0 : 1);
1487 dest = source + 1;
1488
1489 /* Certain instructions expect the destination to be
1490 in the i.rm.reg field. This is by far the
1491 exceptional case. For these instructions, if the
1492 source operand is a register, we must reverse the
1493 i.rm.reg and i.rm.regmem fields. We accomplish
1494 this by pretending that the two register operands
1495 were given in the reverse order. */
1496 if (i.tm.opcode_modifier & ReverseRegRegmem)
1497 {
1498 reg_entry *tmp = i.regs[source];
1499 i.regs[source] = i.regs[dest];
1500 i.regs[dest] = tmp;
1501 }
1502
1503 i.rm.mode = 3;
1504 /* We must be careful to make sure that all
1505 segment/control/test/debug/MMX registers go into
1506 the i.rm.reg field (despite whether they are
1507 source or destination operands). */
1508 if (i.regs[dest]->reg_type
1509 & (SReg2 | SReg3 | Control | Debug | Test | RegMMX))
1510 {
1511 i.rm.reg = i.regs[dest]->reg_num;
1512 i.rm.regmem = i.regs[source]->reg_num;
1513 }
1514 else
1515 {
1516 i.rm.reg = i.regs[source]->reg_num;
1517 i.rm.regmem = i.regs[dest]->reg_num;
1518 }
1519 }
1520 else
1521 { /* if it's not 2 reg operands... */
1522 if (i.mem_operands)
1523 {
1524 unsigned int fake_zero_displacement = 0;
1525 unsigned int op = ((i.types[0] & Mem)
1526 ? 0
1527 : (i.types[1] & Mem) ? 1 : 2);
1528
1529 /* Encode memory operand into modrm byte and base index
1530 byte. */
1531
1532 if (i.base_reg == esp && !i.index_reg)
1533 {
1534 /* <disp>(%esp) becomes two byte modrm with no index
1535 register. */
1536 i.rm.regmem = ESCAPE_TO_TWO_BYTE_ADDRESSING;
1537 i.rm.mode = mode_from_disp_size (i.types[op]);
1538 i.bi.base = ESP_REG_NUM;
1539 i.bi.index = NO_INDEX_REGISTER;
1540 i.bi.scale = 0; /* Must be zero! */
1541 }
1542 else if (i.base_reg == ebp && !i.index_reg)
1543 {
1544 if (!(i.types[op] & Disp))
1545 {
1546 /* Must fake a zero byte displacement. There is
1547 no direct way to code '(%ebp)' directly. */
1548 fake_zero_displacement = 1;
1549 /* fake_zero_displacement code does not set this. */
1550 i.types[op] |= Disp8;
1551 }
1552 i.rm.mode = mode_from_disp_size (i.types[op]);
1553 i.rm.regmem = EBP_REG_NUM;
1554 }
1555 else if (!i.base_reg && (i.types[op] & BaseIndex))
1556 {
1557 /* There are three cases here.
1558 Case 1: '<32bit disp>(,1)' -- indirect absolute.
1559 (Same as cases 2 & 3 with NO index register)
1560 Case 2: <32bit disp> (,<index>) -- no base register with disp
1561 Case 3: (, <index>) --- no base register;
1562 no disp (must add 32bit 0 disp). */
1563 i.rm.regmem = ESCAPE_TO_TWO_BYTE_ADDRESSING;
1564 i.rm.mode = 0; /* 32bit mode */
1565 i.bi.base = NO_BASE_REGISTER;
1566 i.types[op] &= ~Disp;
1567 i.types[op] |= Disp32; /* Must be 32bit! */
1568 if (i.index_reg)
1569 { /* case 2 or case 3 */
1570 i.bi.index = i.index_reg->reg_num;
1571 i.bi.scale = i.log2_scale_factor;
1572 if (i.disp_operands == 0)
1573 fake_zero_displacement = 1; /* case 3 */
1574 }
1575 else
1576 {
1577 i.bi.index = NO_INDEX_REGISTER;
1578 i.bi.scale = 0;
1579 }
1580 }
1581 else if (i.disp_operands && !i.base_reg && !i.index_reg)
1582 {
1583 /* Operand is just <32bit disp> */
1584 i.rm.regmem = EBP_REG_NUM;
1585 i.rm.mode = 0;
1586 i.types[op] &= ~Disp;
1587 i.types[op] |= Disp32;
1588 }
1589 else
1590 {
1591 /* It's not a special case; rev'em up. */
1592 i.rm.regmem = i.base_reg->reg_num;
1593 i.rm.mode = mode_from_disp_size (i.types[op]);
1594 if (i.index_reg)
1595 {
1596 i.rm.regmem = ESCAPE_TO_TWO_BYTE_ADDRESSING;
1597 i.bi.base = i.base_reg->reg_num;
1598 i.bi.index = i.index_reg->reg_num;
1599 i.bi.scale = i.log2_scale_factor;
1600 if (i.base_reg == ebp && i.disp_operands == 0)
1601 { /* pace */
1602 fake_zero_displacement = 1;
1603 i.types[op] |= Disp8;
1604 i.rm.mode = mode_from_disp_size (i.types[op]);
1605 }
1606 }
1607 }
1608 if (fake_zero_displacement)
1609 {
1610 /* Fakes a zero displacement assuming that i.types[op]
1611 holds the correct displacement size. */
1612 exp = &disp_expressions[i.disp_operands++];
1613 i.disps[op] = exp;
1614 exp->X_op = O_constant;
1615 exp->X_add_number = 0;
1616 exp->X_add_symbol = (symbolS *) 0;
1617 exp->X_op_symbol = (symbolS *) 0;
1618 }
1619
1620 /* Find the default segment for the memory operand.
1621 Used to optimize out explicit segment specifications. */
1622 if (i.seg[0])
1623 {
1624 unsigned int seg_index;
1625
1626 if (i.rm.regmem == ESCAPE_TO_TWO_BYTE_ADDRESSING)
1627 {
1628 seg_index = (i.rm.mode << 3) | i.bi.base;
1629 default_seg = two_byte_segment_defaults[seg_index];
1630 }
1631 else
1632 {
1633 seg_index = (i.rm.mode << 3) | i.rm.regmem;
1634 default_seg = one_byte_segment_defaults[seg_index];
1635 }
1636 }
1637 }
1638
1639 /* Fill in i.rm.reg or i.rm.regmem field with register
1640 operand (if any) based on i.tm.extension_opcode.
1641 Again, we must be careful to make sure that
1642 segment/control/debug/test/MMX registers are coded
1643 into the i.rm.reg field. */
1644 if (i.reg_operands)
1645 {
1646 unsigned int op =
1647 ((i.types[0]
1648 & (Reg | SReg2 | SReg3 | Control | Debug
1649 | Test | RegMMX))
1650 ? 0
1651 : ((i.types[1]
1652 & (Reg | SReg2 | SReg3 | Control | Debug
1653 | Test | RegMMX))
1654 ? 1
1655 : 2));
1656 /* If there is an extension opcode to put here, the
1657 register number must be put into the regmem field. */
1658 if (i.tm.extension_opcode != None)
1659 i.rm.regmem = i.regs[op]->reg_num;
1660 else
1661 i.rm.reg = i.regs[op]->reg_num;
1662
1663 /* Now, if no memory operand has set i.rm.mode = 0, 1, 2
1664 we must set it to 3 to indicate this is a register
1665 operand in the regmem field. */
1666 if (!i.mem_operands)
1667 i.rm.mode = 3;
1668 }
1669
1670 /* Fill in i.rm.reg field with extension opcode (if any). */
1671 if (i.tm.extension_opcode != None)
1672 i.rm.reg = i.tm.extension_opcode;
1673 }
1674
1675 if (i.rm.mode != 3)
1676 uses_mem_addrmode = 1;
1677 }
1678 else if (i.tm.opcode_modifier & Seg2ShortForm)
1679 {
1680 if (i.tm.base_opcode == POP_SEG_SHORT && i.regs[0]->reg_num == 1)
1681 {
1682 as_bad ("you can't `pop %%cs' on the 386.");
1683 return;
1684 }
1685 i.tm.base_opcode |= (i.regs[0]->reg_num << 3);
1686 }
1687 else if (i.tm.opcode_modifier & Seg3ShortForm)
1688 {
1689 /* 'push %fs' is 0x0fa0; 'pop %fs' is 0x0fa1.
1690 'push %gs' is 0x0fa8; 'pop %fs' is 0x0fa9.
1691 So, only if i.regs[0]->reg_num == 5 (%gs) do we need
1692 to change the opcode. */
1693 if (i.regs[0]->reg_num == 5)
1694 i.tm.base_opcode |= 0x08;
1695 }
1696 else if ((i.tm.base_opcode & ~DW) == MOV_AX_DISP32)
1697 {
1698 /* This is a special non-modrm instruction
1699 that addresses memory with a 32-bit displacement mode anyway,
1700 and thus requires an address-size prefix if in 16-bit mode. */
1701 uses_mem_addrmode = 1;
1702 default_seg = &ds;
1703 }
1704 else if ((i.tm.opcode_modifier & IsString) != 0)
1705 {
1706 /* For the string instructions that allow a segment override
1707 on one of their operands, the default segment is ds. */
1708 default_seg = &ds;
1709 }
1710
1711 /* GAS currently doesn't support 16-bit memory addressing modes at all,
1712 so if we're writing 16-bit code and using a memory addressing mode,
1713 always spew out an address size prefix. */
1714 if (uses_mem_addrmode && flag_16bit_code)
1715 {
1716 if (! check_prefix (ADDR_PREFIX_OPCODE))
1717 return;
1718 i.prefix[i.prefixes++] = ADDR_PREFIX_OPCODE;
1719 }
1720
1721 /* If a segment was explicitly specified,
1722 and the specified segment is not the default,
1723 use an opcode prefix to select it.
1724 If we never figured out what the default segment is,
1725 then default_seg will be zero at this point,
1726 and the specified segment prefix will always be used. */
1727 if ((i.seg[0]) && (i.seg[0] != default_seg))
1728 {
1729 if (! check_prefix (i.seg[0]->seg_prefix))
1730 return;
1731 i.prefix[i.prefixes++] = i.seg[0]->seg_prefix;
1732 }
1733 }
1734 }
1735
1736 /* Handle conversion of 'int $3' --> special int3 insn. */
1737 if (i.tm.base_opcode == INT_OPCODE && i.imms[0]->X_add_number == 3)
1738 {
1739 i.tm.base_opcode = INT3_OPCODE;
1740 i.imm_operands = 0;
1741 }
1742
1743 /* We are ready to output the insn. */
1744 {
1745 register char *p;
1746
1747 /* Output jumps. */
1748 if (i.tm.opcode_modifier & Jump)
1749 {
1750 unsigned long n = i.disps[0]->X_add_number;
1751
1752 if (i.prefixes != 0)
1753 as_warn ("skipping prefixes on this instruction");
1754
1755 if (i.disps[0]->X_op == O_constant)
1756 {
1757 if (fits_in_signed_byte (n))
1758 {
1759 p = frag_more (2);
1760 insn_size += 2;
1761 p[0] = i.tm.base_opcode;
1762 p[1] = n;
1763 }
1764 else
1765 { /* It's an absolute word/dword displacement. */
1766
1767 /* Use 16-bit jumps only for 16-bit code,
1768 because text segments are limited to 64K anyway;
1769 Use 32-bit jumps for 32-bit code, because they're faster,
1770 and a 16-bit jump will clear the top 16 bits of %eip. */
1771 int jmp_size = flag_16bit_code ? 2 : 4;
1772 if (flag_16bit_code && !fits_in_signed_word (n))
1773 {
1774 as_bad (_("16-bit jump out of range"));
1775 return;
1776 }
1777
1778 if (i.tm.base_opcode == JUMP_PC_RELATIVE)
1779 { /* pace */
1780 /* unconditional jump */
1781 p = frag_more (1 + jmp_size);
1782 insn_size += 1 + jmp_size;
1783 p[0] = (char) 0xe9;
1784 md_number_to_chars (&p[1], (valueT) n, jmp_size);
1785 }
1786 else
1787 {
1788 /* conditional jump */
1789 p = frag_more (2 + jmp_size);
1790 insn_size += 2 + jmp_size;
1791 p[0] = TWO_BYTE_OPCODE_ESCAPE;
1792 p[1] = i.tm.base_opcode + 0x10;
1793 md_number_to_chars (&p[2], (valueT) n, jmp_size);
1794 }
1795 }
1796 }
1797 else
1798 {
1799 if (flag_16bit_code)
1800 {
1801 FRAG_APPEND_1_CHAR (WORD_PREFIX_OPCODE);
1802 insn_size += 1;
1803 }
1804
1805 /* It's a symbol; end frag & setup for relax.
1806 Make sure there are more than 6 chars left in the current frag;
1807 if not we'll have to start a new one. */
1808 frag_grow (7);
1809 p = frag_more (1);
1810 insn_size += 1;
1811 p[0] = i.tm.base_opcode;
1812 frag_var (rs_machine_dependent,
1813 6, /* 2 opcode/prefix + 4 displacement */
1814 1,
1815 ((unsigned char) *p == JUMP_PC_RELATIVE
1816 ? ENCODE_RELAX_STATE (UNCOND_JUMP, BYTE)
1817 : ENCODE_RELAX_STATE (COND_JUMP, BYTE)),
1818 i.disps[0]->X_add_symbol,
1819 (offsetT) n, p);
1820 }
1821 }
1822 else if (i.tm.opcode_modifier & (JumpByte | JumpDword))
1823 {
1824 int size = (i.tm.opcode_modifier & JumpByte) ? 1 : 4;
1825 unsigned long n = i.disps[0]->X_add_number;
1826 unsigned char *q;
1827
1828 /* The jcx/jecx instruction might need a data size prefix. */
1829 for (q = i.prefix; q < i.prefix + i.prefixes; q++)
1830 {
1831 if (*q == WORD_PREFIX_OPCODE)
1832 {
1833 /* The jcxz/jecxz instructions are marked with Data16
1834 and Data32, which means that they may get
1835 WORD_PREFIX_OPCODE added to the list of prefixes.
1836 However, the are correctly distinguished using
1837 ADDR_PREFIX_OPCODE. Here we look for
1838 WORD_PREFIX_OPCODE, and actually emit
1839 ADDR_PREFIX_OPCODE. This is a hack, but, then, so
1840 is the instruction itself.
1841
1842 If an explicit suffix is used for the loop
1843 instruction, that actually controls whether we use
1844 cx vs. ecx. This is also controlled by
1845 ADDR_PREFIX_OPCODE.
1846
1847 I don't know if there is any valid case in which we
1848 want to emit WORD_PREFIX_OPCODE, but I am keeping
1849 the old behaviour for safety. */
1850
1851 if (IS_JUMP_ON_CX_ZERO (i.tm.base_opcode)
1852 || IS_LOOP_ECX_TIMES (i.tm.base_opcode))
1853 FRAG_APPEND_1_CHAR (ADDR_PREFIX_OPCODE);
1854 else
1855 FRAG_APPEND_1_CHAR (WORD_PREFIX_OPCODE);
1856 insn_size += 1;
1857 break;
1858 }
1859 }
1860
1861 if ((size == 4) && (flag_16bit_code))
1862 {
1863 FRAG_APPEND_1_CHAR (WORD_PREFIX_OPCODE);
1864 insn_size += 1;
1865 }
1866
1867 if (fits_in_unsigned_byte (i.tm.base_opcode))
1868 {
1869 FRAG_APPEND_1_CHAR (i.tm.base_opcode);
1870 insn_size += 1;
1871 }
1872 else
1873 {
1874 p = frag_more (2); /* opcode can be at most two bytes */
1875 insn_size += 2;
1876 /* put out high byte first: can't use md_number_to_chars! */
1877 *p++ = (i.tm.base_opcode >> 8) & 0xff;
1878 *p = i.tm.base_opcode & 0xff;
1879 }
1880
1881 p = frag_more (size);
1882 insn_size += size;
1883 if (i.disps[0]->X_op == O_constant)
1884 {
1885 md_number_to_chars (p, (valueT) n, size);
1886 if (size == 1 && !fits_in_signed_byte (n))
1887 {
1888 as_bad (_("loop/jecx only takes byte displacement; %lu shortened to %d"),
1889 n, *p);
1890 }
1891 }
1892 else
1893 {
1894 fix_new_exp (frag_now, p - frag_now->fr_literal, size,
1895 i.disps[0], 1, reloc (size, 1, i.disp_reloc[0]));
1896
1897 }
1898 }
1899 else if (i.tm.opcode_modifier & JumpInterSegment)
1900 {
1901 if (i.prefixes != 0)
1902 as_warn ("skipping prefixes on this instruction");
1903
1904 if (flag_16bit_code)
1905 {
1906 FRAG_APPEND_1_CHAR (WORD_PREFIX_OPCODE);
1907 insn_size += 1;
1908 }
1909
1910 p = frag_more (1 + 2 + 4); /* 1 opcode; 2 segment; 4 offset */
1911 insn_size += 1 + 2 + 4;
1912 p[0] = i.tm.base_opcode;
1913 if (i.imms[1]->X_op == O_constant)
1914 md_number_to_chars (p + 1, (valueT) i.imms[1]->X_add_number, 4);
1915 else
1916 fix_new_exp (frag_now, p + 1 - frag_now->fr_literal, 4,
1917 i.imms[1], 0, BFD_RELOC_32);
1918 if (i.imms[0]->X_op != O_constant)
1919 as_bad (_("can't handle non absolute segment in long call/jmp"));
1920 md_number_to_chars (p + 5, (valueT) i.imms[0]->X_add_number, 2);
1921 }
1922 else
1923 {
1924 /* Output normal instructions here. */
1925 unsigned char *q;
1926
1927 /* Hack for fwait. It must come before any prefixes, as it
1928 really is an instruction rather than a prefix. */
1929 if ((i.tm.opcode_modifier & FWait) != 0)
1930 {
1931 p = frag_more (1);
1932 insn_size += 1;
1933 md_number_to_chars (p, (valueT) FWAIT_OPCODE, 1);
1934 }
1935
1936 /* The prefix bytes. */
1937 for (q = i.prefix; q < i.prefix + i.prefixes; q++)
1938 {
1939 p = frag_more (1);
1940 insn_size += 1;
1941 md_number_to_chars (p, (valueT) *q, 1);
1942 }
1943
1944 /* Now the opcode; be careful about word order here! */
1945 if (fits_in_unsigned_byte (i.tm.base_opcode))
1946 {
1947 FRAG_APPEND_1_CHAR (i.tm.base_opcode);
1948 insn_size += 1;
1949 }
1950 else if (fits_in_unsigned_word (i.tm.base_opcode))
1951 {
1952 p = frag_more (2);
1953 insn_size += 2;
1954 /* put out high byte first: can't use md_number_to_chars! */
1955 *p++ = (i.tm.base_opcode >> 8) & 0xff;
1956 *p = i.tm.base_opcode & 0xff;
1957 }
1958 else
1959 { /* opcode is either 3 or 4 bytes */
1960 if (i.tm.base_opcode & 0xff000000)
1961 {
1962 p = frag_more (4);
1963 insn_size += 4;
1964 *p++ = (i.tm.base_opcode >> 24) & 0xff;
1965 }
1966 else
1967 {
1968 p = frag_more (3);
1969 insn_size += 3;
1970 }
1971 *p++ = (i.tm.base_opcode >> 16) & 0xff;
1972 *p++ = (i.tm.base_opcode >> 8) & 0xff;
1973 *p = (i.tm.base_opcode) & 0xff;
1974 }
1975
1976 /* Now the modrm byte and base index byte (if present). */
1977 if (i.tm.opcode_modifier & Modrm)
1978 {
1979 p = frag_more (1);
1980 insn_size += 1;
1981 /* md_number_to_chars (p, i.rm, 1); */
1982 md_number_to_chars (p,
1983 (valueT) (i.rm.regmem << 0
1984 | i.rm.reg << 3
1985 | i.rm.mode << 6),
1986 1);
1987 /* If i.rm.regmem == ESP (4) && i.rm.mode != Mode 3 (Register mode)
1988 ==> need second modrm byte. */
1989 if (i.rm.regmem == ESCAPE_TO_TWO_BYTE_ADDRESSING && i.rm.mode != 3)
1990 {
1991 p = frag_more (1);
1992 insn_size += 1;
1993 /* md_number_to_chars (p, i.bi, 1); */
1994 md_number_to_chars (p, (valueT) (i.bi.base << 0
1995 | i.bi.index << 3
1996 | i.bi.scale << 6),
1997 1);
1998 }
1999 }
2000
2001 if (i.disp_operands)
2002 {
2003 register unsigned int n;
2004
2005 for (n = 0; n < i.operands; n++)
2006 {
2007 if (i.disps[n])
2008 {
2009 if (i.disps[n]->X_op == O_constant)
2010 {
2011 if (i.types[n] & (Disp8 | Abs8))
2012 {
2013 p = frag_more (1);
2014 insn_size += 1;
2015 md_number_to_chars (p,
2016 (valueT) i.disps[n]->X_add_number,
2017 1);
2018 }
2019 else if (i.types[n] & (Disp16 | Abs16))
2020 {
2021 p = frag_more (2);
2022 insn_size += 2;
2023 md_number_to_chars (p,
2024 (valueT) i.disps[n]->X_add_number,
2025 2);
2026 }
2027 else
2028 { /* Disp32|Abs32 */
2029 p = frag_more (4);
2030 insn_size += 4;
2031 md_number_to_chars (p,
2032 (valueT) i.disps[n]->X_add_number,
2033 4);
2034 }
2035 }
2036 else
2037 { /* not absolute_section */
2038 /* need a 32-bit fixup (don't support 8bit non-absolute disps) */
2039 p = frag_more (4);
2040 insn_size += 4;
2041 fix_new_exp (frag_now, p - frag_now->fr_literal, 4,
2042 i.disps[n], 0,
2043 TC_RELOC(i.disp_reloc[n], BFD_RELOC_32));
2044 }
2045 }
2046 }
2047 } /* end displacement output */
2048
2049 /* output immediate */
2050 if (i.imm_operands)
2051 {
2052 register unsigned int n;
2053
2054 for (n = 0; n < i.operands; n++)
2055 {
2056 if (i.imms[n])
2057 {
2058 if (i.imms[n]->X_op == O_constant)
2059 {
2060 if (i.types[n] & (Imm8 | Imm8S))
2061 {
2062 p = frag_more (1);
2063 insn_size += 1;
2064 md_number_to_chars (p,
2065 (valueT) i.imms[n]->X_add_number,
2066 1);
2067 }
2068 else if (i.types[n] & Imm16)
2069 {
2070 p = frag_more (2);
2071 insn_size += 2;
2072 md_number_to_chars (p,
2073 (valueT) i.imms[n]->X_add_number,
2074 2);
2075 }
2076 else
2077 {
2078 p = frag_more (4);
2079 insn_size += 4;
2080 md_number_to_chars (p,
2081 (valueT) i.imms[n]->X_add_number,
2082 4);
2083 }
2084 }
2085 else
2086 { /* not absolute_section */
2087 /* Need a 32-bit fixup (don't support 8bit
2088 non-absolute ims). Try to support other
2089 sizes ... */
2090 int r_type;
2091 int size;
2092 int pcrel = 0;
2093
2094 if (i.types[n] & (Imm8 | Imm8S))
2095 size = 1;
2096 else if (i.types[n] & Imm16)
2097 size = 2;
2098 else
2099 size = 4;
2100 r_type = reloc (size, 0, i.disp_reloc[0]);
2101 p = frag_more (size);
2102 insn_size += size;
2103 #ifdef BFD_ASSEMBLER
2104 if (r_type == BFD_RELOC_32
2105 && GOT_symbol
2106 && GOT_symbol == i.imms[n]->X_add_symbol
2107 && (i.imms[n]->X_op == O_symbol
2108 || (i.imms[n]->X_op == O_add
2109 && (i.imms[n]->X_op_symbol->sy_value.X_op
2110 == O_subtract))))
2111 {
2112 r_type = BFD_RELOC_386_GOTPC;
2113 i.imms[n]->X_add_number += 3;
2114 }
2115 #endif
2116 fix_new_exp (frag_now, p - frag_now->fr_literal, size,
2117 i.imms[n], pcrel, r_type);
2118 }
2119 }
2120 }
2121 } /* end immediate output */
2122 }
2123
2124 #ifdef DEBUG386
2125 if (flag_debug)
2126 {
2127 pi (line, &i);
2128 }
2129 #endif /* DEBUG386 */
2130 }
2131 }
2132 \f
2133 /* Parse OPERAND_STRING into the i386_insn structure I. Returns non-zero
2134 on error. */
2135
2136 static int
2137 i386_operand (operand_string)
2138 char *operand_string;
2139 {
2140 register char *op_string = operand_string;
2141
2142 /* Address of '\0' at end of operand_string. */
2143 char *end_of_operand_string = operand_string + strlen (operand_string);
2144
2145 /* Start and end of displacement string expression (if found). */
2146 char *displacement_string_start = NULL;
2147 char *displacement_string_end = NULL;
2148
2149 /* We check for an absolute prefix (differentiating,
2150 for example, 'jmp pc_relative_label' from 'jmp *absolute_label'. */
2151 if (*op_string == ABSOLUTE_PREFIX)
2152 {
2153 op_string++;
2154 i.types[this_operand] |= JumpAbsolute;
2155 }
2156
2157 /* Check if operand is a register. */
2158 if (*op_string == REGISTER_PREFIX)
2159 {
2160 register reg_entry *r;
2161 if (!(r = parse_register (op_string)))
2162 {
2163 as_bad (_("bad register name `%s'"), op_string);
2164 return 0;
2165 }
2166 /* Check for segment override, rather than segment register by
2167 searching for ':' after %<x>s where <x> = s, c, d, e, f, g. */
2168 if ((r->reg_type & (SReg2 | SReg3)) && op_string[3] == ':')
2169 {
2170 switch (r->reg_num)
2171 {
2172 case 0:
2173 i.seg[i.mem_operands] = (seg_entry *) & es;
2174 break;
2175 case 1:
2176 i.seg[i.mem_operands] = (seg_entry *) & cs;
2177 break;
2178 case 2:
2179 i.seg[i.mem_operands] = (seg_entry *) & ss;
2180 break;
2181 case 3:
2182 i.seg[i.mem_operands] = (seg_entry *) & ds;
2183 break;
2184 case 4:
2185 i.seg[i.mem_operands] = (seg_entry *) & fs;
2186 break;
2187 case 5:
2188 i.seg[i.mem_operands] = (seg_entry *) & gs;
2189 break;
2190 }
2191 op_string += 4; /* skip % <x> s : */
2192 operand_string = op_string; /* Pretend given string starts here. */
2193 if (!is_digit_char (*op_string) && !is_identifier_char (*op_string)
2194 && *op_string != '(' && *op_string != ABSOLUTE_PREFIX)
2195 {
2196 as_bad (_("bad memory operand `%s'"), op_string);
2197 return 0;
2198 }
2199 /* Handle case of %es:*foo. */
2200 if (*op_string == ABSOLUTE_PREFIX)
2201 {
2202 op_string++;
2203 i.types[this_operand] |= JumpAbsolute;
2204 }
2205 goto do_memory_reference;
2206 }
2207 i.types[this_operand] |= r->reg_type;
2208 i.regs[this_operand] = r;
2209 i.reg_operands++;
2210 }
2211 else if (*op_string == IMMEDIATE_PREFIX)
2212 { /* ... or an immediate */
2213 char *save_input_line_pointer;
2214 segT exp_seg = 0;
2215 expressionS *exp;
2216
2217 if (i.imm_operands == MAX_IMMEDIATE_OPERANDS)
2218 {
2219 as_bad (_("only 1 or 2 immediate operands are allowed"));
2220 return 0;
2221 }
2222
2223 exp = &im_expressions[i.imm_operands++];
2224 i.imms[this_operand] = exp;
2225 save_input_line_pointer = input_line_pointer;
2226 input_line_pointer = ++op_string; /* must advance op_string! */
2227 SKIP_WHITESPACE ();
2228 exp_seg = expression (exp);
2229 if (*input_line_pointer != '\0')
2230 {
2231 /* This should be as_bad, but some versions of gcc, up to
2232 about 2.8 and egcs 1.01, generate a bogus @GOTOFF(%ebx)
2233 in certain cases. Oddly, the code in question turns out
2234 to work correctly anyhow, so we make this just a warning
2235 until those versions of gcc are obsolete. */
2236 as_warn (_("unrecognized characters `%s' in expression"),
2237 input_line_pointer);
2238 }
2239 input_line_pointer = save_input_line_pointer;
2240
2241 if (exp->X_op == O_absent)
2242 {
2243 /* missing or bad expr becomes absolute 0 */
2244 as_bad (_("missing or invalid immediate expression `%s' taken as 0"),
2245 operand_string);
2246 exp->X_op = O_constant;
2247 exp->X_add_number = 0;
2248 exp->X_add_symbol = (symbolS *) 0;
2249 exp->X_op_symbol = (symbolS *) 0;
2250 i.types[this_operand] |= Imm;
2251 }
2252 else if (exp->X_op == O_constant)
2253 {
2254 i.types[this_operand] |=
2255 smallest_imm_type ((unsigned long) exp->X_add_number);
2256 }
2257 #ifdef OBJ_AOUT
2258 else if (exp_seg != text_section
2259 && exp_seg != data_section
2260 && exp_seg != bss_section
2261 && exp_seg != undefined_section
2262 #ifdef BFD_ASSEMBLER
2263 && ! bfd_is_com_section (exp_seg)
2264 #endif
2265 )
2266 {
2267 seg_unimplemented:
2268 as_bad (_("Unimplemented segment type %d in parse_operand"), exp_seg);
2269 return 0;
2270 }
2271 #endif
2272 else
2273 {
2274 /* this is an address ==> 32bit */
2275 i.types[this_operand] |= Imm32;
2276 }
2277 /* shorten this type of this operand if the instruction wants
2278 * fewer bits than are present in the immediate. The bit field
2279 * code can put out 'andb $0xffffff, %al', for example. pace
2280 * also 'movw $foo,(%eax)'
2281 */
2282 switch (i.suffix)
2283 {
2284 case WORD_OPCODE_SUFFIX:
2285 i.types[this_operand] |= Imm16;
2286 break;
2287 case BYTE_OPCODE_SUFFIX:
2288 i.types[this_operand] |= Imm16 | Imm8 | Imm8S;
2289 break;
2290 }
2291 }
2292 else if (is_digit_char (*op_string) || is_identifier_char (*op_string)
2293 || *op_string == '(')
2294 {
2295 /* This is a memory reference of some sort. */
2296 register char *base_string;
2297 unsigned int found_base_index_form;
2298
2299 do_memory_reference:
2300 if ((i.mem_operands == 1
2301 && (current_templates->start->opcode_modifier & IsString) == 0)
2302 || i.mem_operands == 2)
2303 {
2304 as_bad (_("too many memory references for `%s'"),
2305 current_templates->start->name);
2306 return 0;
2307 }
2308 i.mem_operands++;
2309
2310 /* Determine type of memory operand from opcode_suffix;
2311 no opcode suffix implies general memory references. */
2312 switch (i.suffix)
2313 {
2314 case BYTE_OPCODE_SUFFIX:
2315 i.types[this_operand] |= Mem8;
2316 break;
2317 case WORD_OPCODE_SUFFIX:
2318 i.types[this_operand] |= Mem16;
2319 break;
2320 case DWORD_OPCODE_SUFFIX:
2321 default:
2322 i.types[this_operand] |= Mem32;
2323 }
2324
2325 /* Check for base index form. We detect the base index form by
2326 looking for an ')' at the end of the operand, searching
2327 for the '(' matching it, and finding a REGISTER_PREFIX or ','
2328 after it. */
2329 base_string = end_of_operand_string - 1;
2330 found_base_index_form = 0;
2331 if (*base_string == ')')
2332 {
2333 unsigned int parens_balanced = 1;
2334 /* We've already checked that the number of left & right ()'s are
2335 equal, so this loop will not be infinite. */
2336 do
2337 {
2338 base_string--;
2339 if (*base_string == ')')
2340 parens_balanced++;
2341 if (*base_string == '(')
2342 parens_balanced--;
2343 }
2344 while (parens_balanced);
2345 base_string++; /* Skip past '('. */
2346 if (*base_string == REGISTER_PREFIX || *base_string == ',')
2347 found_base_index_form = 1;
2348 }
2349
2350 /* If we can't parse a base index register expression, we've found
2351 a pure displacement expression. We set up displacement_string_start
2352 and displacement_string_end for the code below. */
2353 if (!found_base_index_form)
2354 {
2355 displacement_string_start = op_string;
2356 displacement_string_end = end_of_operand_string;
2357 }
2358 else
2359 {
2360 char *base_reg_name, *index_reg_name, *num_string;
2361 int num;
2362
2363 i.types[this_operand] |= BaseIndex;
2364
2365 /* If there is a displacement set-up for it to be parsed later. */
2366 if (base_string != op_string + 1)
2367 {
2368 displacement_string_start = op_string;
2369 displacement_string_end = base_string - 1;
2370 }
2371
2372 /* Find base register (if any). */
2373 if (*base_string != ',')
2374 {
2375 base_reg_name = base_string++;
2376 /* skip past register name & parse it */
2377 while (isalpha (*base_string))
2378 base_string++;
2379 if (base_string == base_reg_name + 1)
2380 {
2381 as_bad (_("can't find base register name after `(%c'"),
2382 REGISTER_PREFIX);
2383 return 0;
2384 }
2385 END_STRING_AND_SAVE (base_string);
2386 if (!(i.base_reg = parse_register (base_reg_name)))
2387 {
2388 as_bad (_("bad base register name `%s'"), base_reg_name);
2389 RESTORE_END_STRING (base_string);
2390 return 0;
2391 }
2392 RESTORE_END_STRING (base_string);
2393 }
2394
2395 /* Now check seperator; must be ',' ==> index reg
2396 OR num ==> no index reg. just scale factor
2397 OR ')' ==> end. (scale factor = 1) */
2398 if (*base_string != ',' && *base_string != ')')
2399 {
2400 as_bad (_("expecting `,' or `)' after base register in `%s'"),
2401 operand_string);
2402 return 0;
2403 }
2404
2405 /* There may index reg here; and there may be a scale factor. */
2406 if (*base_string == ',' && *(base_string + 1) == REGISTER_PREFIX)
2407 {
2408 index_reg_name = ++base_string;
2409 while (isalpha (*++base_string));
2410 END_STRING_AND_SAVE (base_string);
2411 if (!(i.index_reg = parse_register (index_reg_name)))
2412 {
2413 as_bad (_("bad index register name `%s'"), index_reg_name);
2414 RESTORE_END_STRING (base_string);
2415 return 0;
2416 }
2417 RESTORE_END_STRING (base_string);
2418 }
2419
2420 /* Check for scale factor. */
2421 if (*base_string == ',' && isdigit (*(base_string + 1)))
2422 {
2423 num_string = ++base_string;
2424 while (is_digit_char (*base_string))
2425 base_string++;
2426 if (base_string == num_string)
2427 {
2428 as_bad (_("can't find a scale factor after `,'"));
2429 return 0;
2430 }
2431 END_STRING_AND_SAVE (base_string);
2432 /* We've got a scale factor. */
2433 if (!sscanf (num_string, "%d", &num))
2434 {
2435 as_bad (_("can't parse scale factor from `%s'"), num_string);
2436 RESTORE_END_STRING (base_string);
2437 return 0;
2438 }
2439 RESTORE_END_STRING (base_string);
2440 switch (num)
2441 { /* must be 1 digit scale */
2442 case 1:
2443 i.log2_scale_factor = 0;
2444 break;
2445 case 2:
2446 i.log2_scale_factor = 1;
2447 break;
2448 case 4:
2449 i.log2_scale_factor = 2;
2450 break;
2451 case 8:
2452 i.log2_scale_factor = 3;
2453 break;
2454 default:
2455 as_bad (_("expecting scale factor of 1, 2, 4, 8; got %d"), num);
2456 return 0;
2457 }
2458 }
2459 else
2460 {
2461 if (!i.index_reg && *base_string == ',')
2462 {
2463 as_bad (_("expecting index register or scale factor after `,'; got '%c'"),
2464 *(base_string + 1));
2465 return 0;
2466 }
2467 }
2468 }
2469
2470 /* If there's an expression begining the operand, parse it,
2471 assuming displacement_string_start and displacement_string_end
2472 are meaningful. */
2473 if (displacement_string_start)
2474 {
2475 register expressionS *exp;
2476 segT exp_seg = 0;
2477 char *save_input_line_pointer;
2478 exp = &disp_expressions[i.disp_operands];
2479 i.disps[this_operand] = exp;
2480 i.disp_reloc[this_operand] = NO_RELOC;
2481 i.disp_operands++;
2482 save_input_line_pointer = input_line_pointer;
2483 input_line_pointer = displacement_string_start;
2484 END_STRING_AND_SAVE (displacement_string_end);
2485
2486 #ifndef LEX_AT
2487 {
2488 /*
2489 * We can have operands of the form
2490 * <symbol>@GOTOFF+<nnn>
2491 * Take the easy way out here and copy everything
2492 * into a temporary buffer...
2493 */
2494 register char *cp;
2495
2496 cp = strchr (input_line_pointer, '@');
2497 if (cp != NULL)
2498 {
2499 char *tmpbuf;
2500
2501 if (GOT_symbol == NULL)
2502 GOT_symbol = symbol_find_or_make (GLOBAL_OFFSET_TABLE_NAME);
2503
2504 tmpbuf = (char *) alloca ((cp - input_line_pointer) + 20);
2505
2506 if (strncmp (cp + 1, "PLT", 3) == 0)
2507 {
2508 i.disp_reloc[this_operand] = BFD_RELOC_386_PLT32;
2509 *cp = '\0';
2510 strcpy (tmpbuf, input_line_pointer);
2511 strcat (tmpbuf, cp + 1 + 3);
2512 *cp = '@';
2513 }
2514 else if (strncmp (cp + 1, "GOTOFF", 6) == 0)
2515 {
2516 i.disp_reloc[this_operand] = BFD_RELOC_386_GOTOFF;
2517 *cp = '\0';
2518 strcpy (tmpbuf, input_line_pointer);
2519 strcat (tmpbuf, cp + 1 + 6);
2520 *cp = '@';
2521 }
2522 else if (strncmp (cp + 1, "GOT", 3) == 0)
2523 {
2524 i.disp_reloc[this_operand] = BFD_RELOC_386_GOT32;
2525 *cp = '\0';
2526 strcpy (tmpbuf, input_line_pointer);
2527 strcat (tmpbuf, cp + 1 + 3);
2528 *cp = '@';
2529 }
2530 else
2531 as_bad (_("Bad reloc specifier `%s' in expression"), cp + 1);
2532
2533 input_line_pointer = tmpbuf;
2534 }
2535 }
2536 #endif
2537
2538 exp_seg = expression (exp);
2539
2540 #ifdef BFD_ASSEMBLER
2541 /* We do this to make sure that the section symbol is in
2542 the symbol table. We will ultimately change the relocation
2543 to be relative to the beginning of the section */
2544 if (i.disp_reloc[this_operand] == BFD_RELOC_386_GOTOFF)
2545 {
2546 if (S_IS_LOCAL(exp->X_add_symbol)
2547 && S_GET_SEGMENT (exp->X_add_symbol) != undefined_section)
2548 section_symbol(exp->X_add_symbol->bsym->section);
2549 assert (exp->X_op == O_symbol);
2550 exp->X_op = O_subtract;
2551 exp->X_op_symbol = GOT_symbol;
2552 i.disp_reloc[this_operand] = BFD_RELOC_32;
2553 }
2554 #endif
2555
2556 if (*input_line_pointer)
2557 as_bad (_("Ignoring junk `%s' after expression"),
2558 input_line_pointer);
2559 RESTORE_END_STRING (displacement_string_end);
2560 input_line_pointer = save_input_line_pointer;
2561 if (exp->X_op == O_absent)
2562 {
2563 /* missing expr becomes absolute 0 */
2564 as_bad (_("missing or invalid displacement `%s' taken as 0"),
2565 operand_string);
2566 i.types[this_operand] |= (Disp | Abs);
2567 exp->X_op = O_constant;
2568 exp->X_add_number = 0;
2569 exp->X_add_symbol = (symbolS *) 0;
2570 exp->X_op_symbol = (symbolS *) 0;
2571 }
2572 else if (exp->X_op == O_constant)
2573 {
2574 i.types[this_operand] |= SMALLEST_DISP_TYPE (exp->X_add_number);
2575 }
2576 else if (exp_seg == text_section
2577 || exp_seg == data_section
2578 || exp_seg == bss_section
2579 || exp_seg == undefined_section)
2580 {
2581 i.types[this_operand] |= Disp32;
2582 }
2583 else
2584 {
2585 #ifndef OBJ_AOUT
2586 i.types[this_operand] |= Disp32;
2587 #else
2588 goto seg_unimplemented;
2589 #endif
2590 }
2591 }
2592
2593 /* Make sure the memory operand we've been dealt is valid. */
2594 if (i.base_reg && i.index_reg &&
2595 !(i.base_reg->reg_type & i.index_reg->reg_type & Reg))
2596 {
2597 as_bad (_("register size mismatch in (base,index,scale) expression"));
2598 return 0;
2599 }
2600 /*
2601 * special case for (%dx) while doing input/output op
2602 */
2603 if ((i.base_reg &&
2604 (i.base_reg->reg_type == (Reg16 | InOutPortReg)) &&
2605 (i.index_reg == 0)))
2606 {
2607 i.types[this_operand] |= InOutPortReg;
2608 return 1;
2609 }
2610 if ((i.base_reg && (i.base_reg->reg_type & Reg32) == 0) ||
2611 (i.index_reg && (i.index_reg->reg_type & Reg32) == 0))
2612 {
2613 as_bad (_("base/index register must be 32 bit register"));
2614 return 0;
2615 }
2616 if (i.index_reg && i.index_reg == esp)
2617 {
2618 as_bad (_("`%%s' may not be used as an index register"),
2619 esp->reg_name);
2620 return 0;
2621 }
2622 }
2623 else
2624 { /* it's not a memory operand; argh! */
2625 as_bad (_("invalid char %s begining %s operand `%s'"),
2626 output_invalid (*op_string), ordinal_names[this_operand],
2627 op_string);
2628 return 0;
2629 }
2630 return 1; /* normal return */
2631 }
2632 \f
2633 /*
2634 * md_estimate_size_before_relax()
2635 *
2636 * Called just before relax().
2637 * Any symbol that is now undefined will not become defined.
2638 * Return the correct fr_subtype in the frag.
2639 * Return the initial "guess for fr_var" to caller.
2640 * The guess for fr_var is ACTUALLY the growth beyond fr_fix.
2641 * Whatever we do to grow fr_fix or fr_var contributes to our returned value.
2642 * Although it may not be explicit in the frag, pretend fr_var starts with a
2643 * 0 value.
2644 */
2645 int
2646 md_estimate_size_before_relax (fragP, segment)
2647 register fragS *fragP;
2648 register segT segment;
2649 {
2650 register unsigned char *opcode;
2651 register int old_fr_fix;
2652
2653 old_fr_fix = fragP->fr_fix;
2654 opcode = (unsigned char *) fragP->fr_opcode;
2655 /* We've already got fragP->fr_subtype right; all we have to do is check
2656 for un-relaxable symbols. */
2657 if (S_GET_SEGMENT (fragP->fr_symbol) != segment)
2658 {
2659 /* symbol is undefined in this segment */
2660 switch (opcode[0])
2661 {
2662 case JUMP_PC_RELATIVE: /* make jmp (0xeb) a dword displacement jump */
2663 opcode[0] = 0xe9; /* dword disp jmp */
2664 fragP->fr_fix += 4;
2665 fix_new (fragP, old_fr_fix, 4,
2666 fragP->fr_symbol,
2667 fragP->fr_offset, 1,
2668 (GOT_symbol && /* Not quite right - we should switch on
2669 presence of @PLT, but I cannot see how
2670 to get to that from here. We should have
2671 done this in md_assemble to really
2672 get it right all of the time, but I
2673 think it does not matter that much, as
2674 this will be right most of the time. ERY*/
2675 S_GET_SEGMENT(fragP->fr_symbol) == undefined_section)?
2676 BFD_RELOC_386_PLT32 : BFD_RELOC_32_PCREL);
2677 break;
2678
2679 default:
2680 /* This changes the byte-displacement jump 0x7N -->
2681 the dword-displacement jump 0x0f8N */
2682 opcode[1] = opcode[0] + 0x10;
2683 opcode[0] = TWO_BYTE_OPCODE_ESCAPE; /* two-byte escape */
2684 fragP->fr_fix += 1 + 4; /* we've added an opcode byte */
2685 fix_new (fragP, old_fr_fix + 1, 4,
2686 fragP->fr_symbol,
2687 fragP->fr_offset, 1,
2688 (GOT_symbol && /* Not quite right - we should switch on
2689 presence of @PLT, but I cannot see how
2690 to get to that from here. ERY */
2691 S_GET_SEGMENT(fragP->fr_symbol) == undefined_section)?
2692 BFD_RELOC_386_PLT32 : BFD_RELOC_32_PCREL);
2693 break;
2694 }
2695 frag_wane (fragP);
2696 }
2697 return (fragP->fr_var + fragP->fr_fix - old_fr_fix);
2698 } /* md_estimate_size_before_relax() */
2699 \f
2700 /*
2701 * md_convert_frag();
2702 *
2703 * Called after relax() is finished.
2704 * In: Address of frag.
2705 * fr_type == rs_machine_dependent.
2706 * fr_subtype is what the address relaxed to.
2707 *
2708 * Out: Any fixSs and constants are set up.
2709 * Caller will turn frag into a ".space 0".
2710 */
2711 #ifndef BFD_ASSEMBLER
2712 void
2713 md_convert_frag (headers, sec, fragP)
2714 object_headers *headers;
2715 segT sec;
2716 register fragS *fragP;
2717 #else
2718 void
2719 md_convert_frag (abfd, sec, fragP)
2720 bfd *abfd;
2721 segT sec;
2722 register fragS *fragP;
2723 #endif
2724 {
2725 register unsigned char *opcode;
2726 unsigned char *where_to_put_displacement = NULL;
2727 unsigned int target_address;
2728 unsigned int opcode_address;
2729 unsigned int extension = 0;
2730 int displacement_from_opcode_start;
2731
2732 opcode = (unsigned char *) fragP->fr_opcode;
2733
2734 /* Address we want to reach in file space. */
2735 target_address = S_GET_VALUE (fragP->fr_symbol) + fragP->fr_offset;
2736 #ifdef BFD_ASSEMBLER /* not needed otherwise? */
2737 target_address += fragP->fr_symbol->sy_frag->fr_address;
2738 #endif
2739
2740 /* Address opcode resides at in file space. */
2741 opcode_address = fragP->fr_address + fragP->fr_fix;
2742
2743 /* Displacement from opcode start to fill into instruction. */
2744 displacement_from_opcode_start = target_address - opcode_address;
2745
2746 switch (fragP->fr_subtype)
2747 {
2748 case ENCODE_RELAX_STATE (COND_JUMP, BYTE):
2749 case ENCODE_RELAX_STATE (UNCOND_JUMP, BYTE):
2750 /* don't have to change opcode */
2751 extension = 1; /* 1 opcode + 1 displacement */
2752 where_to_put_displacement = &opcode[1];
2753 break;
2754
2755 case ENCODE_RELAX_STATE (COND_JUMP, WORD):
2756 opcode[1] = TWO_BYTE_OPCODE_ESCAPE;
2757 opcode[2] = opcode[0] + 0x10;
2758 opcode[0] = WORD_PREFIX_OPCODE;
2759 extension = 4; /* 3 opcode + 2 displacement */
2760 where_to_put_displacement = &opcode[3];
2761 break;
2762
2763 case ENCODE_RELAX_STATE (UNCOND_JUMP, WORD):
2764 opcode[1] = 0xe9;
2765 opcode[0] = WORD_PREFIX_OPCODE;
2766 extension = 3; /* 2 opcode + 2 displacement */
2767 where_to_put_displacement = &opcode[2];
2768 break;
2769
2770 case ENCODE_RELAX_STATE (COND_JUMP, DWORD):
2771 opcode[1] = opcode[0] + 0x10;
2772 opcode[0] = TWO_BYTE_OPCODE_ESCAPE;
2773 extension = 5; /* 2 opcode + 4 displacement */
2774 where_to_put_displacement = &opcode[2];
2775 break;
2776
2777 case ENCODE_RELAX_STATE (UNCOND_JUMP, DWORD):
2778 opcode[0] = 0xe9;
2779 extension = 4; /* 1 opcode + 4 displacement */
2780 where_to_put_displacement = &opcode[1];
2781 break;
2782
2783 default:
2784 BAD_CASE (fragP->fr_subtype);
2785 break;
2786 }
2787 /* now put displacement after opcode */
2788 md_number_to_chars ((char *) where_to_put_displacement,
2789 (valueT) (displacement_from_opcode_start - extension),
2790 SIZE_FROM_RELAX_STATE (fragP->fr_subtype));
2791 fragP->fr_fix += extension;
2792 }
2793 \f
2794
2795 int md_short_jump_size = 2; /* size of byte displacement jmp */
2796 int md_long_jump_size = 5; /* size of dword displacement jmp */
2797 const int md_reloc_size = 8; /* Size of relocation record */
2798
2799 void
2800 md_create_short_jump (ptr, from_addr, to_addr, frag, to_symbol)
2801 char *ptr;
2802 addressT from_addr, to_addr;
2803 fragS *frag;
2804 symbolS *to_symbol;
2805 {
2806 long offset;
2807
2808 offset = to_addr - (from_addr + 2);
2809 md_number_to_chars (ptr, (valueT) 0xeb, 1); /* opcode for byte-disp jump */
2810 md_number_to_chars (ptr + 1, (valueT) offset, 1);
2811 }
2812
2813 void
2814 md_create_long_jump (ptr, from_addr, to_addr, frag, to_symbol)
2815 char *ptr;
2816 addressT from_addr, to_addr;
2817 fragS *frag;
2818 symbolS *to_symbol;
2819 {
2820 long offset;
2821
2822 if (flag_do_long_jump)
2823 {
2824 offset = to_addr - S_GET_VALUE (to_symbol);
2825 md_number_to_chars (ptr, (valueT) 0xe9, 1);/* opcode for long jmp */
2826 md_number_to_chars (ptr + 1, (valueT) offset, 4);
2827 fix_new (frag, (ptr + 1) - frag->fr_literal, 4,
2828 to_symbol, (offsetT) 0, 0, BFD_RELOC_32);
2829 }
2830 else
2831 {
2832 offset = to_addr - (from_addr + 5);
2833 md_number_to_chars (ptr, (valueT) 0xe9, 1);
2834 md_number_to_chars (ptr + 1, (valueT) offset, 4);
2835 }
2836 }
2837 \f
2838 /* Apply a fixup (fixS) to segment data, once it has been determined
2839 by our caller that we have all the info we need to fix it up.
2840
2841 On the 386, immediates, displacements, and data pointers are all in
2842 the same (little-endian) format, so we don't need to care about which
2843 we are handling. */
2844
2845 int
2846 md_apply_fix3 (fixP, valp, seg)
2847 fixS *fixP; /* The fix we're to put in. */
2848 valueT *valp; /* Pointer to the value of the bits. */
2849 segT seg; /* Segment fix is from. */
2850 {
2851 register char *p = fixP->fx_where + fixP->fx_frag->fr_literal;
2852 valueT value = *valp;
2853
2854 if (fixP->fx_r_type == BFD_RELOC_32 && fixP->fx_pcrel)
2855 fixP->fx_r_type = BFD_RELOC_32_PCREL;
2856
2857 #if defined (BFD_ASSEMBLER) && !defined (TE_Mach)
2858 /*
2859 * This is a hack. There should be a better way to
2860 * handle this.
2861 */
2862 if (fixP->fx_r_type == BFD_RELOC_32_PCREL && fixP->fx_addsy)
2863 {
2864 #ifndef OBJ_AOUT
2865 if (OUTPUT_FLAVOR == bfd_target_elf_flavour
2866 || OUTPUT_FLAVOR == bfd_target_coff_flavour)
2867 value += fixP->fx_where + fixP->fx_frag->fr_address;
2868 #endif
2869 #if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
2870 if (OUTPUT_FLAVOR == bfd_target_elf_flavour
2871 && (S_GET_SEGMENT (fixP->fx_addsy) == seg
2872 || (fixP->fx_addsy->bsym->flags & BSF_SECTION_SYM) != 0))
2873 {
2874 /* Yes, we add the values in twice. This is because
2875 bfd_perform_relocation subtracts them out again. I think
2876 bfd_perform_relocation is broken, but I don't dare change
2877 it. FIXME. */
2878 value += fixP->fx_where + fixP->fx_frag->fr_address;
2879 }
2880 #endif
2881 #if defined (OBJ_COFF) && defined (TE_PE)
2882 /* For some reason, the PE format does not store a section
2883 address offset for a PC relative symbol. */
2884 if (S_GET_SEGMENT (fixP->fx_addsy) != seg)
2885 value += md_pcrel_from (fixP);
2886 #endif
2887 }
2888
2889 /* Fix a few things - the dynamic linker expects certain values here,
2890 and we must not dissappoint it. */
2891 #if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
2892 if (OUTPUT_FLAVOR == bfd_target_elf_flavour
2893 && fixP->fx_addsy)
2894 switch(fixP->fx_r_type) {
2895 case BFD_RELOC_386_PLT32:
2896 /* Make the jump instruction point to the address of the operand. At
2897 runtime we merely add the offset to the actual PLT entry. */
2898 value = 0xfffffffc;
2899 break;
2900 case BFD_RELOC_386_GOTPC:
2901 /*
2902 * This is tough to explain. We end up with this one if we have
2903 * operands that look like "_GLOBAL_OFFSET_TABLE_+[.-.L284]". The goal
2904 * here is to obtain the absolute address of the GOT, and it is strongly
2905 * preferable from a performance point of view to avoid using a runtime
2906 * relocation for this. The actual sequence of instructions often look
2907 * something like:
2908 *
2909 * call .L66
2910 * .L66:
2911 * popl %ebx
2912 * addl $_GLOBAL_OFFSET_TABLE_+[.-.L66],%ebx
2913 *
2914 * The call and pop essentially return the absolute address of
2915 * the label .L66 and store it in %ebx. The linker itself will
2916 * ultimately change the first operand of the addl so that %ebx points to
2917 * the GOT, but to keep things simple, the .o file must have this operand
2918 * set so that it generates not the absolute address of .L66, but the
2919 * absolute address of itself. This allows the linker itself simply
2920 * treat a GOTPC relocation as asking for a pcrel offset to the GOT to be
2921 * added in, and the addend of the relocation is stored in the operand
2922 * field for the instruction itself.
2923 *
2924 * Our job here is to fix the operand so that it would add the correct
2925 * offset so that %ebx would point to itself. The thing that is tricky is
2926 * that .-.L66 will point to the beginning of the instruction, so we need
2927 * to further modify the operand so that it will point to itself.
2928 * There are other cases where you have something like:
2929 *
2930 * .long $_GLOBAL_OFFSET_TABLE_+[.-.L66]
2931 *
2932 * and here no correction would be required. Internally in the assembler
2933 * we treat operands of this form as not being pcrel since the '.' is
2934 * explicitly mentioned, and I wonder whether it would simplify matters
2935 * to do it this way. Who knows. In earlier versions of the PIC patches,
2936 * the pcrel_adjust field was used to store the correction, but since the
2937 * expression is not pcrel, I felt it would be confusing to do it this way.
2938 */
2939 value -= 1;
2940 break;
2941 case BFD_RELOC_386_GOT32:
2942 value = 0; /* Fully resolved at runtime. No addend. */
2943 break;
2944 case BFD_RELOC_386_GOTOFF:
2945 break;
2946
2947 default:
2948 break;
2949 }
2950 #endif
2951
2952 #endif
2953 md_number_to_chars (p, value, fixP->fx_size);
2954
2955 return 1;
2956 }
2957
2958 #if 0
2959 /* This is never used. */
2960 long /* Knows about the byte order in a word. */
2961 md_chars_to_number (con, nbytes)
2962 unsigned char con[]; /* Low order byte 1st. */
2963 int nbytes; /* Number of bytes in the input. */
2964 {
2965 long retval;
2966 for (retval = 0, con += nbytes - 1; nbytes--; con--)
2967 {
2968 retval <<= BITS_PER_CHAR;
2969 retval |= *con;
2970 }
2971 return retval;
2972 }
2973 #endif /* 0 */
2974 \f
2975
2976 #define MAX_LITTLENUMS 6
2977
2978 /* Turn the string pointed to by litP into a floating point constant of type
2979 type, and emit the appropriate bytes. The number of LITTLENUMS emitted
2980 is stored in *sizeP . An error message is returned, or NULL on OK. */
2981 char *
2982 md_atof (type, litP, sizeP)
2983 char type;
2984 char *litP;
2985 int *sizeP;
2986 {
2987 int prec;
2988 LITTLENUM_TYPE words[MAX_LITTLENUMS];
2989 LITTLENUM_TYPE *wordP;
2990 char *t;
2991
2992 switch (type)
2993 {
2994 case 'f':
2995 case 'F':
2996 prec = 2;
2997 break;
2998
2999 case 'd':
3000 case 'D':
3001 prec = 4;
3002 break;
3003
3004 case 'x':
3005 case 'X':
3006 prec = 5;
3007 break;
3008
3009 default:
3010 *sizeP = 0;
3011 return _("Bad call to md_atof ()");
3012 }
3013 t = atof_ieee (input_line_pointer, type, words);
3014 if (t)
3015 input_line_pointer = t;
3016
3017 *sizeP = prec * sizeof (LITTLENUM_TYPE);
3018 /* This loops outputs the LITTLENUMs in REVERSE order; in accord with
3019 the bigendian 386. */
3020 for (wordP = words + prec - 1; prec--;)
3021 {
3022 md_number_to_chars (litP, (valueT) (*wordP--), sizeof (LITTLENUM_TYPE));
3023 litP += sizeof (LITTLENUM_TYPE);
3024 }
3025 return 0;
3026 }
3027 \f
3028 char output_invalid_buf[8];
3029
3030 static char *
3031 output_invalid (c)
3032 char c;
3033 {
3034 if (isprint (c))
3035 sprintf (output_invalid_buf, "'%c'", c);
3036 else
3037 sprintf (output_invalid_buf, "(0x%x)", (unsigned) c);
3038 return output_invalid_buf;
3039 }
3040
3041 /* reg_string starts *before* REGISTER_PREFIX */
3042 static reg_entry *
3043 parse_register (reg_string)
3044 char *reg_string;
3045 {
3046 register char *s = reg_string;
3047 register char *p;
3048 char reg_name_given[MAX_REG_NAME_SIZE];
3049
3050 s++; /* skip REGISTER_PREFIX */
3051 for (p = reg_name_given; is_register_char (*s); p++, s++)
3052 {
3053 *p = register_chars[(unsigned char) *s];
3054 if (p >= reg_name_given + MAX_REG_NAME_SIZE)
3055 return (reg_entry *) 0;
3056 }
3057 *p = '\0';
3058 return (reg_entry *) hash_find (reg_hash, reg_name_given);
3059 }
3060 \f
3061 #ifdef OBJ_ELF
3062 CONST char *md_shortopts = "kmVQ:";
3063 #else
3064 CONST char *md_shortopts = "m";
3065 #endif
3066 struct option md_longopts[] = {
3067 {NULL, no_argument, NULL, 0}
3068 };
3069 size_t md_longopts_size = sizeof(md_longopts);
3070
3071 int
3072 md_parse_option (c, arg)
3073 int c;
3074 char *arg;
3075 {
3076 switch (c)
3077 {
3078 case 'm':
3079 flag_do_long_jump = 1;
3080 break;
3081
3082 #if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
3083 /* -k: Ignore for FreeBSD compatibility. */
3084 case 'k':
3085 break;
3086
3087 /* -V: SVR4 argument to print version ID. */
3088 case 'V':
3089 print_version_id ();
3090 break;
3091
3092 /* -Qy, -Qn: SVR4 arguments controlling whether a .comment section
3093 should be emitted or not. FIXME: Not implemented. */
3094 case 'Q':
3095 break;
3096 #endif
3097
3098 default:
3099 return 0;
3100 }
3101 return 1;
3102 }
3103
3104 void
3105 md_show_usage (stream)
3106 FILE *stream;
3107 {
3108 fprintf (stream, _("\
3109 -m do long jump\n"));
3110 }
3111
3112 #ifdef BFD_ASSEMBLER
3113 #ifdef OBJ_MAYBE_ELF
3114 #ifdef OBJ_MAYBE_COFF
3115
3116 /* Pick the target format to use. */
3117
3118 const char *
3119 i386_target_format ()
3120 {
3121 switch (OUTPUT_FLAVOR)
3122 {
3123 case bfd_target_coff_flavour:
3124 return "coff-i386";
3125 case bfd_target_elf_flavour:
3126 return "elf32-i386";
3127 default:
3128 abort ();
3129 return NULL;
3130 }
3131 }
3132
3133 #endif /* OBJ_MAYBE_COFF */
3134 #endif /* OBJ_MAYBE_ELF */
3135 #endif /* BFD_ASSEMBLER */
3136 \f
3137 /* ARGSUSED */
3138 symbolS *
3139 md_undefined_symbol (name)
3140 char *name;
3141 {
3142 if (*name == '_' && *(name+1) == 'G'
3143 && strcmp(name, GLOBAL_OFFSET_TABLE_NAME) == 0)
3144 {
3145 if(!GOT_symbol)
3146 {
3147 if(symbol_find(name))
3148 as_bad(_("GOT already in symbol table"));
3149 GOT_symbol = symbol_new (name, undefined_section,
3150 (valueT) 0, &zero_address_frag);
3151 };
3152 return GOT_symbol;
3153 }
3154 return 0;
3155 }
3156
3157 /* Round up a section size to the appropriate boundary. */
3158 valueT
3159 md_section_align (segment, size)
3160 segT segment;
3161 valueT size;
3162 {
3163 #ifdef OBJ_AOUT
3164 #ifdef BFD_ASSEMBLER
3165 /* For a.out, force the section size to be aligned. If we don't do
3166 this, BFD will align it for us, but it will not write out the
3167 final bytes of the section. This may be a bug in BFD, but it is
3168 easier to fix it here since that is how the other a.out targets
3169 work. */
3170 int align;
3171
3172 align = bfd_get_section_alignment (stdoutput, segment);
3173 size = ((size + (1 << align) - 1) & ((valueT) -1 << align));
3174 #endif
3175 #endif
3176
3177 return size;
3178 }
3179
3180 /* Exactly what point is a PC-relative offset relative TO? On the
3181 i386, they're relative to the address of the offset, plus its
3182 size. (??? Is this right? FIXME-SOON!) */
3183 long
3184 md_pcrel_from (fixP)
3185 fixS *fixP;
3186 {
3187 return fixP->fx_size + fixP->fx_where + fixP->fx_frag->fr_address;
3188 }
3189
3190 #ifndef I386COFF
3191
3192 static void
3193 s_bss (ignore)
3194 int ignore;
3195 {
3196 register int temp;
3197
3198 temp = get_absolute_expression ();
3199 subseg_set (bss_section, (subsegT) temp);
3200 demand_empty_rest_of_line ();
3201 }
3202
3203 #endif
3204
3205
3206 #ifdef BFD_ASSEMBLER
3207
3208 void
3209 i386_validate_fix (fixp)
3210 fixS *fixp;
3211 {
3212 if (fixp->fx_subsy && fixp->fx_subsy == GOT_symbol)
3213 {
3214 fixp->fx_r_type = BFD_RELOC_386_GOTOFF;
3215 fixp->fx_subsy = 0;
3216 }
3217 }
3218
3219 #define F(SZ,PCREL) (((SZ) << 1) + (PCREL))
3220 #define MAP(SZ,PCREL,TYPE) case F(SZ,PCREL): code = (TYPE); break
3221
3222 arelent *
3223 tc_gen_reloc (section, fixp)
3224 asection *section;
3225 fixS *fixp;
3226 {
3227 arelent *rel;
3228 bfd_reloc_code_real_type code;
3229
3230 switch(fixp->fx_r_type)
3231 {
3232 case BFD_RELOC_386_PLT32:
3233 case BFD_RELOC_386_GOT32:
3234 case BFD_RELOC_386_GOTOFF:
3235 case BFD_RELOC_386_GOTPC:
3236 case BFD_RELOC_RVA:
3237 code = fixp->fx_r_type;
3238 break;
3239 default:
3240 switch (F (fixp->fx_size, fixp->fx_pcrel))
3241 {
3242 MAP (1, 0, BFD_RELOC_8);
3243 MAP (2, 0, BFD_RELOC_16);
3244 MAP (4, 0, BFD_RELOC_32);
3245 MAP (1, 1, BFD_RELOC_8_PCREL);
3246 MAP (2, 1, BFD_RELOC_16_PCREL);
3247 MAP (4, 1, BFD_RELOC_32_PCREL);
3248 default:
3249 if (fixp->fx_pcrel)
3250 as_bad (_("Can not do %d byte pc-relative relocation"),
3251 fixp->fx_size);
3252 else
3253 as_bad (_("Can not do %d byte relocation"), fixp->fx_size);
3254 }
3255 }
3256 #undef MAP
3257 #undef F
3258
3259 if (code == BFD_RELOC_32
3260 && GOT_symbol
3261 && fixp->fx_addsy == GOT_symbol)
3262 code = BFD_RELOC_386_GOTPC;
3263
3264 rel = (arelent *) xmalloc (sizeof (arelent));
3265 rel->sym_ptr_ptr = &fixp->fx_addsy->bsym;
3266 rel->address = fixp->fx_frag->fr_address + fixp->fx_where;
3267 if (fixp->fx_pcrel)
3268 rel->addend = fixp->fx_addnumber;
3269 else
3270 rel->addend = 0;
3271
3272 rel->howto = bfd_reloc_type_lookup (stdoutput, code);
3273 if (rel->howto == NULL)
3274 {
3275 as_bad_where (fixp->fx_file, fixp->fx_line,
3276 _("Cannot represent relocation type %s"),
3277 bfd_get_reloc_code_name (code));
3278 /* Set howto to a garbage value so that we can keep going. */
3279 rel->howto = bfd_reloc_type_lookup (stdoutput, BFD_RELOC_32);
3280 assert (rel->howto != NULL);
3281 }
3282
3283 return rel;
3284 }
3285
3286 #else /* ! BFD_ASSEMBLER */
3287
3288 #if (defined(OBJ_AOUT) | defined(OBJ_BOUT))
3289 void
3290 tc_aout_fix_to_chars (where, fixP, segment_address_in_file)
3291 char *where;
3292 fixS *fixP;
3293 relax_addressT segment_address_in_file;
3294 {
3295 /*
3296 * In: length of relocation (or of address) in chars: 1, 2 or 4.
3297 * Out: GNU LD relocation length code: 0, 1, or 2.
3298 */
3299
3300 static const unsigned char nbytes_r_length[] = {42, 0, 1, 42, 2};
3301 long r_symbolnum;
3302
3303 know (fixP->fx_addsy != NULL);
3304
3305 md_number_to_chars (where,
3306 (valueT) (fixP->fx_frag->fr_address
3307 + fixP->fx_where - segment_address_in_file),
3308 4);
3309
3310 r_symbolnum = (S_IS_DEFINED (fixP->fx_addsy)
3311 ? S_GET_TYPE (fixP->fx_addsy)
3312 : fixP->fx_addsy->sy_number);
3313
3314 where[6] = (r_symbolnum >> 16) & 0x0ff;
3315 where[5] = (r_symbolnum >> 8) & 0x0ff;
3316 where[4] = r_symbolnum & 0x0ff;
3317 where[7] = ((((!S_IS_DEFINED (fixP->fx_addsy)) << 3) & 0x08)
3318 | ((nbytes_r_length[fixP->fx_size] << 1) & 0x06)
3319 | (((fixP->fx_pcrel << 0) & 0x01) & 0x0f));
3320 }
3321
3322 #endif /* OBJ_AOUT or OBJ_BOUT */
3323
3324 #if defined (I386COFF)
3325
3326 short
3327 tc_coff_fix2rtype (fixP)
3328 fixS *fixP;
3329 {
3330 if (fixP->fx_r_type == R_IMAGEBASE)
3331 return R_IMAGEBASE;
3332
3333 return (fixP->fx_pcrel ?
3334 (fixP->fx_size == 1 ? R_PCRBYTE :
3335 fixP->fx_size == 2 ? R_PCRWORD :
3336 R_PCRLONG) :
3337 (fixP->fx_size == 1 ? R_RELBYTE :
3338 fixP->fx_size == 2 ? R_RELWORD :
3339 R_DIR32));
3340 }
3341
3342 int
3343 tc_coff_sizemachdep (frag)
3344 fragS *frag;
3345 {
3346 if (frag->fr_next)
3347 return (frag->fr_next->fr_address - frag->fr_address);
3348 else
3349 return 0;
3350 }
3351
3352 #endif /* I386COFF */
3353
3354 #endif /* BFD_ASSEMBLER? */
3355 \f
3356 /* end of tc-i386.c */