gas/config/tc-i386.h

   1 /* tc-i386.h -- Header file for tc-i386.c
   2    Copyright (C) 1989, 92, 93, 94, 95, 96, 97, 98, 1999
   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 #ifndef TC_I386
  23 #define TC_I386 1
  24
  25 #ifdef ANSI_PROTOTYPES
  26 struct fix;
  27 #endif
  28
  29 #define TARGET_BYTES_BIG_ENDIAN 0
  30
  31 #ifdef TE_LYNX
  32 #define TARGET_FORMAT           "coff-i386-lynx"
  33 #endif
  34
  35 #ifdef BFD_ASSEMBLER
  36 /* This is used to determine relocation types in tc-i386.c.  The first
  37    parameter is the current relocation type, the second one is the desired
  38    type.  The idea is that if the original type is already some kind of PIC
  39    relocation, we leave it alone, otherwise we give it the desired type */
  40
  41 #define TC_RELOC(X,Y) (((X) != BFD_RELOC_386_PLT32 && \
  42            (X) != BFD_RELOC_386_GOTOFF && \
  43            (X) != BFD_RELOC_386_GOT32 && \
  44            (X) != BFD_RELOC_386_GOTPC) ? Y : X)
  45
  46 #define tc_fix_adjustable(X)  tc_i386_fix_adjustable(X)
  47 extern int tc_i386_fix_adjustable PARAMS ((struct fix *));
  48
  49 /* This is the relocation type for direct references to GLOBAL_OFFSET_TABLE.
  50  * It comes up in complicated expressions such as
  51  * _GLOBAL_OFFSET_TABLE_+[.-.L284], which cannot be expressed normally with
  52  * the regular expressions.  The fixup specified here when used at runtime
  53  * implies that we should add the address of the GOT to the specified location,
  54  * and as a result we have simplified the expression into something we can use.
  55  */
  56 #define TC_RELOC_GLOBAL_OFFSET_TABLE BFD_RELOC_386_GOTPC
  57
  58 /* This expression evaluates to false if the relocation is for a local object
  59    for which we still want to do the relocation at runtime.  True if we
  60    are willing to perform this relocation while building the .o file.
  61    This is only used for pcrel relocations, so GOTOFF does not need to be
  62    checked here.  I am not sure if some of the others are ever used with
  63    pcrel, but it is easier to be safe than sorry. */
  64
  65 #define TC_RELOC_RTSYM_LOC_FIXUP(FIX)                           \
  66   ((FIX)->fx_r_type != BFD_RELOC_386_PLT32                      \
  67    && (FIX)->fx_r_type != BFD_RELOC_386_GOT32                   \
  68    && (FIX)->fx_r_type != BFD_RELOC_386_GOTPC                   \
  69    && ((FIX)->fx_addsy == NULL                                  \
  70        || (! S_IS_EXTERNAL ((FIX)->fx_addsy)                    \
  71            && ! S_IS_WEAK ((FIX)->fx_addsy)                     \
  72            && S_IS_DEFINED ((FIX)->fx_addsy)                    \
  73            && ! S_IS_COMMON ((FIX)->fx_addsy))))
  74
  75 #define TARGET_ARCH             bfd_arch_i386
  76
  77 #ifdef OBJ_AOUT
  78 #ifdef TE_NetBSD
  79 #define TARGET_FORMAT           "a.out-i386-netbsd"
  80 #endif
  81 #ifdef TE_386BSD
  82 #define TARGET_FORMAT           "a.out-i386-bsd"
  83 #endif
  84 #ifdef TE_LINUX
  85 #define TARGET_FORMAT           "a.out-i386-linux"
  86 #endif
  87 #ifdef TE_Mach
  88 #define TARGET_FORMAT           "a.out-mach3"
  89 #endif
  90 #ifdef TE_DYNIX
  91 #define TARGET_FORMAT           "a.out-i386-dynix"
  92 #endif
  93 #ifndef TARGET_FORMAT
  94 #define TARGET_FORMAT           "a.out-i386"
  95 #endif
  96 #endif /* OBJ_AOUT */
  97
  98 #ifdef OBJ_ELF
  99 #define TARGET_FORMAT           "elf32-i386"
 100 #endif
 101
 102 #ifdef OBJ_MAYBE_ELF
 103 #ifdef OBJ_MAYBE_COFF
 104 extern const char *i386_target_format PARAMS ((void));
 105 #define TARGET_FORMAT i386_target_format ()
 106 #endif
 107 #endif
 108
 109 #else /* ! BFD_ASSEMBLER */
 110
 111 /* COFF STUFF */
 112
 113 #define COFF_MAGIC I386MAGIC
 114 #define BFD_ARCH bfd_arch_i386
 115 #define COFF_FLAGS F_AR32WR
 116 #define TC_COUNT_RELOC(x) ((x)->fx_addsy || (x)->fx_r_type==7)
 117 #define TC_COFF_FIX2RTYPE(fixP) tc_coff_fix2rtype(fixP)
 118 extern short tc_coff_fix2rtype PARAMS ((struct fix *));
 119 #define TC_COFF_SIZEMACHDEP(frag) tc_coff_sizemachdep(frag)
 120 extern int tc_coff_sizemachdep PARAMS ((fragS *frag));
 121
 122 #ifdef TE_GO32
 123 /* DJGPP now expects some sections to be 2**4 aligned.  */
 124 #define SUB_SEGMENT_ALIGN(SEG)                                          \
 125   ((strcmp (obj_segment_name (SEG), ".text") == 0                       \
 126     || strcmp (obj_segment_name (SEG), ".data") == 0                    \
 127     || strncmp (obj_segment_name (SEG), ".gnu.linkonce.t", 15) == 0     \
 128     || strncmp (obj_segment_name (SEG), ".gnu.linkonce.d", 15) == 0     \
 129     || strncmp (obj_segment_name (SEG), ".gnu.linkonce.r", 15) == 0)    \
 130    ? 4                                                                  \
 131    : 2)
 132 #else
 133 #define SUB_SEGMENT_ALIGN(SEG) 2
 134 #endif
 135
 136 #define TC_RVA_RELOC 7
 137 /* Need this for PIC relocations */
 138 #define NEED_FX_R_TYPE
 139
 140
 141 #ifdef TE_386BSD
 142 /* The BSDI linker apparently rejects objects with a machine type of
 143    M_386 (100).  */
 144 #define AOUT_MACHTYPE 0
 145 #else
 146 #define AOUT_MACHTYPE 100
 147 #endif
 148
 149 #undef REVERSE_SORT_RELOCS
 150
 151 #endif /* ! BFD_ASSEMBLER */
 152
 153 #define TC_FORCE_RELOCATION(fixp) tc_i386_force_relocation(fixp)
 154 extern int tc_i386_force_relocation PARAMS ((struct fix *));
 155
 156 #ifdef BFD_ASSEMBLER
 157 #define NO_RELOC BFD_RELOC_NONE
 158 #else
 159 #define NO_RELOC 0
 160 #endif
 161 #define tc_coff_symbol_emit_hook(a)     ;       /* not used */
 162
 163 #ifndef BFD_ASSEMBLER
 164 #ifndef OBJ_AOUT
 165 #ifndef TE_PE
 166 #ifndef TE_GO32
 167 /* Local labels starts with .L */
 168 #define LOCAL_LABEL(name) (name[0] == '.' \
 169                  && (name[1] == 'L' || name[1] == 'X' || name[1] == '.'))
 170 #endif
 171 #endif
 172 #endif
 173 #endif
 174
 175 #define LOCAL_LABELS_FB 1
 176
 177 #define tc_aout_pre_write_hook(x)       {;}     /* not used */
 178 #define tc_crawl_symbol_chain(a)        {;}     /* not used */
 179 #define tc_headers_hook(a)              {;}     /* not used */
 180
 181 extern const char extra_symbol_chars[];
 182 #define tc_symbol_chars extra_symbol_chars
 183
 184 #define MAX_OPERANDS 3          /* max operands per insn */
 185 #define MAX_IMMEDIATE_OPERANDS 2/* max immediates per insn (lcall, ljmp) */
 186 #define MAX_MEMORY_OPERANDS 2   /* max memory refs per insn (string ops) */
 187
 188 /* Prefixes will be emitted in the order defined below.
 189    WAIT_PREFIX must be the first prefix since FWAIT is really is an
 190    instruction, and so must come before any prefixes. */
 191 #define WAIT_PREFIX     0
 192 #define LOCKREP_PREFIX  1
 193 #define ADDR_PREFIX     2
 194 #define DATA_PREFIX     3
 195 #define SEG_PREFIX      4
 196 #define MAX_PREFIXES    5       /* max prefixes per opcode */
 197
 198 /* we define the syntax here (modulo base,index,scale syntax) */
 199 #define REGISTER_PREFIX '%'
 200 #define IMMEDIATE_PREFIX '$'
 201 #define ABSOLUTE_PREFIX '*'
 202
 203 #define TWO_BYTE_OPCODE_ESCAPE 0x0f
 204 #define NOP_OPCODE (char) 0x90
 205
 206 /* register numbers */
 207 #define EBP_REG_NUM 5
 208 #define ESP_REG_NUM 4
 209
 210 /* modrm_byte.regmem for twobyte escape */
 211 #define ESCAPE_TO_TWO_BYTE_ADDRESSING ESP_REG_NUM
 212 /* index_base_byte.index for no index register addressing */
 213 #define NO_INDEX_REGISTER ESP_REG_NUM
 214 /* index_base_byte.base for no base register addressing */
 215 #define NO_BASE_REGISTER EBP_REG_NUM
 216 #define NO_BASE_REGISTER_16 6
 217
 218 /* these are the instruction mnemonic suffixes.  */
 219 #define WORD_MNEM_SUFFIX  'w'
 220 #define BYTE_MNEM_SUFFIX  'b'
 221 #define SHORT_MNEM_SUFFIX 's'
 222 #define LONG_MNEM_SUFFIX  'l'
 223 /* Intel Syntax */
 224 #define LONG_DOUBLE_MNEM_SUFFIX 'x'
 225 /* Intel Syntax */
 226 #define DWORD_MNEM_SUFFIX 'd'
 227
 228 /* modrm.mode = REGMEM_FIELD_HAS_REG when a register is in there */
 229 #define REGMEM_FIELD_HAS_REG 0x3/* always = 0x3 */
 230 #define REGMEM_FIELD_HAS_MEM (~REGMEM_FIELD_HAS_REG)
 231
 232 #define END_OF_INSN '\0'
 233
 234 /* Intel Syntax */
 235 /* Values 0-4 map onto scale factor */
 236 #define BYTE_PTR     0
 237 #define WORD_PTR     1
 238 #define DWORD_PTR    2
 239 #define QWORD_PTR    3
 240 #define XWORD_PTR    4
 241 #define SHORT        5
 242 #define OFFSET_FLAT  6
 243 #define FLAT         7
 244 #define NONE_FOUND   8
 245 /*
 246   When an operand is read in it is classified by its type.  This type includes
 247   all the possible ways an operand can be used.  Thus, '%eax' is both 'register
 248   # 0' and 'The Accumulator'.  In our language this is expressed by OR'ing
 249   'Reg32' (any 32 bit register) and 'Acc' (the accumulator).
 250   Operands are classified so that we can match given operand types with
 251   the opcode table in opcode/i386.h.
 252   */
 253 /* register */
 254 #define Reg8               0x1  /* 8 bit reg */
 255 #define Reg16              0x2  /* 16 bit reg */
 256 #define Reg32              0x4  /* 32 bit reg */
 257 /* immediate */
 258 #define Imm8               0x8  /* 8 bit immediate */
 259 #define Imm8S             0x10  /* 8 bit immediate sign extended */
 260 #define Imm16             0x20  /* 16 bit immediate */
 261 #define Imm32             0x40  /* 32 bit immediate */
 262 #define Imm1              0x80  /* 1 bit immediate */
 263 /* memory */
 264 #define BaseIndex        0x100
 265 /* Disp8,16,32 are used in different ways, depending on the
 266    instruction.  For jumps, they specify the size of the PC relative
 267    displacement, for baseindex type instructions, they specify the
 268    size of the offset relative to the base register, and for memory
 269    offset instructions such as `mov 1234,%al' they specify the size of
 270    the offset relative to the segment base.  */
 271 #define Disp8            0x200  /* 8 bit displacement */
 272 #define Disp16           0x400  /* 16 bit displacement */
 273 #define Disp32           0x800  /* 32 bit displacement */
 274 /* specials */
 275 #define InOutPortReg    0x1000  /* register to hold in/out port addr = dx */
 276 #define ShiftCount      0x2000  /* register to hold shift cound = cl */
 277 #define Control         0x4000  /* Control register */
 278 #define Debug           0x8000  /* Debug register */
 279 #define Test           0x10000  /* Test register */
 280 #define FloatReg       0x20000  /* Float register */
 281 #define FloatAcc       0x40000  /* Float stack top %st(0) */
 282 #define SReg2          0x80000  /* 2 bit segment register */
 283 #define SReg3         0x100000  /* 3 bit segment register */
 284 #define Acc           0x200000  /* Accumulator %al or %ax or %eax */
 285 #define JumpAbsolute  0x400000
 286 #define RegMMX        0x800000  /* MMX register */
 287 #define RegXMM       0x1000000  /* XMM registers in PIII */
 288 #define EsSeg        0x2000000  /* String insn operand with fixed es segment */
 289 /* InvMem is for instructions with a modrm byte that only allow a
 290    general register encoding in the i.tm.mode and i.tm.regmem fields,
 291    eg. control reg moves.  They really ought to support a memory form,
 292    but don't, so we add an InvMem flag to the register operand to
 293    indicate that it should be encoded in the i.tm.regmem field.  */
 294 #define InvMem       0x4000000
 295
 296 #define Reg     (Reg8|Reg16|Reg32)      /* gen'l register */
 297 #define WordReg (Reg16|Reg32)
 298 #define ImplicitRegister (InOutPortReg|ShiftCount|Acc|FloatAcc)
 299 #define Imm     (Imm8|Imm8S|Imm16|Imm32) /* gen'l immediate */
 300 #define Disp    (Disp8|Disp16|Disp32)   /* General displacement */
 301 #define AnyMem  (Disp|BaseIndex|InvMem) /* General memory */
 302 /* The following aliases are defined because the opcode table
 303    carefully specifies the allowed memory types for each instruction.
 304    At the moment we can only tell a memory reference size by the
 305    instruction suffix, so there's not much point in defining Mem8,
 306    Mem16, Mem32 and Mem64 opcode modifiers - We might as well just use
 307    the suffix directly to check memory operands.  */
 308 #define LLongMem AnyMem         /* 64 bits (or more) */
 309 #define LongMem AnyMem          /* 32 bit memory ref */
 310 #define ShortMem AnyMem         /* 16 bit memory ref */
 311 #define WordMem AnyMem          /* 16 or 32 bit memory ref */
 312 #define ByteMem AnyMem          /* 8 bit memory ref */
 313
 314 #define SMALLEST_DISP_TYPE(num) \
 315     (fits_in_signed_byte(num) ? (Disp8|Disp32) : Disp32)
 316
 317 typedef struct
 318 {
 319   /* instruction name sans width suffix ("mov" for movl insns) */
 320   char *name;
 321
 322   /* how many operands */
 323   unsigned int operands;
 324
 325   /* base_opcode is the fundamental opcode byte without optional
 326      prefix(es).  */
 327   unsigned int base_opcode;
 328
 329   /* extension_opcode is the 3 bit extension for group <n> insns.
 330      This field is also used to store the 8-bit opcode suffix for the
 331      AMD 3DNow! instructions.
 332      If this template has no extension opcode (the usual case) use None */
 333   unsigned int extension_opcode;
 334 #define None 0xffff             /* If no extension_opcode is possible. */
 335
 336   /* the bits in opcode_modifier are used to generate the final opcode from
 337      the base_opcode.  These bits also are used to detect alternate forms of
 338      the same instruction */
 339   unsigned int opcode_modifier;
 340
 341   /* opcode_modifier bits: */
 342 #define W                  0x1  /* set if operands can be words or dwords
 343                                    encoded the canonical way */
 344 #define D                  0x2  /* D = 0 if Reg --> Regmem;
 345                                    D = 1 if Regmem --> Reg:    MUST BE 0x2 */
 346 #define Modrm              0x4
 347 #define FloatR             0x8  /* src/dest swap for floats:   MUST BE 0x8 */
 348 #define ShortForm         0x10  /* register is in low 3 bits of opcode */
 349 #define FloatMF           0x20  /* FP insn memory format bit, sized by 0x4 */
 350 #define Jump              0x40  /* special case for jump insns. */
 351 #define JumpDword         0x80  /* call and jump */
 352 #define JumpByte         0x100  /* loop and jecxz */
 353 #define JumpInterSegment 0x200  /* special case for intersegment leaps/calls */
 354 #define FloatD           0x400  /* direction for float insns:  MUST BE 0x400 */
 355 #define Seg2ShortForm    0x800  /* encoding of load segment reg insns */
 356 #define Seg3ShortForm   0x1000  /* fs/gs segment register insns. */
 357 #define Size16          0x2000  /* needs size prefix if in 32-bit mode */
 358 #define Size32          0x4000  /* needs size prefix if in 16-bit mode */
 359 #define IgnoreSize      0x8000  /* instruction ignores operand size prefix */
 360 #define DefaultSize    0x10000  /* default insn size depends on mode */
 361 #define No_bSuf        0x20000  /* b suffix on instruction illegal */
 362 #define No_wSuf        0x40000  /* w suffix on instruction illegal */
 363 #define No_lSuf        0x80000  /* l suffix on instruction illegal */
 364 #define No_sSuf       0x100000  /* s suffix on instruction illegal */
 365 #define No_dSuf       0x200000  /* d suffix on instruction illegal */
 366 #define No_xSuf       0x400000  /* x suffix on instruction illegal */
 367 #define FWait         0x800000  /* instruction needs FWAIT */
 368 #define IsString     0x1000000  /* quick test for string instructions */
 369 #define regKludge    0x2000000  /* fake an extra reg operand for clr, imul */
 370 #define IsPrefix     0x4000000  /* opcode is a prefix */
 371 #define ImmExt       0x8000000  /* instruction has extension in 8 bit imm */
 372 #define Ugh         0x80000000  /* deprecated fp insn, gets a warning */
 373
 374   /* operand_types[i] describes the type of operand i.  This is made
 375      by OR'ing together all of the possible type masks.  (e.g.
 376      'operand_types[i] = Reg|Imm' specifies that operand i can be
 377      either a register or an immediate operand */
 378   unsigned int operand_types[3];
 379 }
 380 template;
 381
 382 /*
 383   'templates' is for grouping together 'template' structures for opcodes
 384   of the same name.  This is only used for storing the insns in the grand
 385   ole hash table of insns.
 386   The templates themselves start at START and range up to (but not including)
 387   END.
 388   */
 389 typedef struct
 390   {
 391     const template *start;
 392     const template *end;
 393   } templates;
 394
 395 /* these are for register name --> number & type hash lookup */
 396 typedef struct
 397   {
 398     char *reg_name;
 399     unsigned int reg_type;
 400     unsigned int reg_num;
 401   }
 402 reg_entry;
 403
 404 typedef struct
 405   {
 406     char *seg_name;
 407     unsigned int seg_prefix;
 408   }
 409 seg_entry;
 410
 411 /* 386 operand encoding bytes:  see 386 book for details of this. */
 412 typedef struct
 413   {
 414     unsigned int regmem;        /* codes register or memory operand */
 415     unsigned int reg;           /* codes register operand (or extended opcode) */
 416     unsigned int mode;          /* how to interpret regmem & reg */
 417   }
 418 modrm_byte;
 419
 420 /* 386 opcode byte to code indirect addressing. */
 421 typedef struct
 422   {
 423     unsigned base;
 424     unsigned index;
 425     unsigned scale;
 426   }
 427 sib_byte;
 428
 429 /* The name of the global offset table generated by the compiler. Allow
 430    this to be overridden if need be. */
 431 #ifndef GLOBAL_OFFSET_TABLE_NAME
 432 #define GLOBAL_OFFSET_TABLE_NAME "_GLOBAL_OFFSET_TABLE_"
 433 #endif
 434
 435 #ifdef BFD_ASSEMBLER
 436 void i386_validate_fix PARAMS ((struct fix *));
 437 #define TC_VALIDATE_FIX(FIXP,SEGTYPE,SKIP) i386_validate_fix(FIXP)
 438 #endif
 439
 440 #endif /* TC_I386 */
 441
 442 #define md_operand(x)
 443
 444 extern const struct relax_type md_relax_table[];
 445 #define TC_GENERIC_RELAX_TABLE md_relax_table
 446
 447 #define md_do_align(n, fill, len, max, around)                          \
 448 if ((n) && !need_pass_2                                                 \
 449     && (!(fill) || ((char)*(fill) == (char)0x90 && (len) == 1))         \
 450     && subseg_text_p (now_seg))                                         \
 451   {                                                                     \
 452     char *p;                                                            \
 453     p = frag_var (rs_align_code, 15, 1, (relax_substateT) max,          \
 454                   (symbolS *) 0, (offsetT) (n), (char *) 0);            \
 455     *p = 0x90;                                                          \
 456     goto around;                                                        \
 457   }
 458
 459 extern void i386_align_code PARAMS ((fragS *, int));
 460
 461 #define HANDLE_ALIGN(fragP)                                             \
 462 if (fragP->fr_type == rs_align_code)                                    \
 463   i386_align_code (fragP, (fragP->fr_next->fr_address                   \
 464                            - fragP->fr_address                          \
 465                            - fragP->fr_fix));
 466
 467 /* call md_apply_fix3 with segment instead of md_apply_fix */
 468 #define MD_APPLY_FIX3
 469
 470 void i386_print_statistics PARAMS ((FILE *));
 471 #define tc_print_statistics i386_print_statistics
 472
 473 #define md_number_to_chars number_to_chars_littleendian
 474
 475 #ifdef SCO_ELF
 476 #define tc_init_after_args() sco_id ()
 477 extern void sco_id PARAMS ((void));
 478 #endif
 479
 480 #define DIFF_EXPR_OK    /* foo-. gets turned into PC relative relocs */
 481
 482 /* end of tc-i386.h */