gas/config/tc-i386.h

   1 /* tc-i386.h -- Header file for tc-i386.c
   2    Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation.
   3
   4    This file is part of GAS, the GNU Assembler.
   5
   6    GAS is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    GAS is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GAS; see the file COPYING.  If not, write to
  18    the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #ifndef TC_I386
  21 #define TC_I386 1
  22
  23 #ifdef TE_LYNX
  24 #define TARGET_FORMAT           "coff-i386-lynx"
  25 #endif
  26
  27 #ifdef BFD_ASSEMBLER
  28 /* This is used to determine relocation types in tc-i386.c.  The first
  29    parameter is the current relocation type, the second one is the desired
  30    type.  The idea is that if the original type is already some kind of PIC
  31    relocation, we leave it alone, otherwise we give it the desired type */
  32
  33 #define TC_RELOC(X,Y) (((X) != BFD_RELOC_386_PLT32 && \
  34            (X) != BFD_RELOC_386_GOTOFF && \
  35            (X) != BFD_RELOC_386_GOT32 && \
  36            (X) != BFD_RELOC_386_GOTPC) ? Y : X)
  37
  38 #define tc_fix_adjustable(X)  tc_i386_fix_adjustable(X)
  39
  40 /* This is the relocation type for direct references to GLOBAL_OFFSET_TABLE.
  41  * It comes up in complicated expressions such as
  42  * _GLOBAL_OFFSET_TABLE_+[.-.L284], which cannot be expressed normally with
  43  * the regular expressions.  The fixup specified here when used at runtime
  44  * implies that we should add the address of the GOT to the specified location,
  45  * and as a result we have simplified the expression into something we can use.
  46  */
  47 #define TC_RELOC_GLOBAL_OFFSET_TABLE BFD_RELOC_386_GOTPC
  48
  49 /* This expression evaluates to false if the relocation is for a local object
  50    for which we still want to do the relocation at runtime.  True if we
  51    are willing to perform this relocation while building the .o file.
  52    This is only used for pcrel relocations, so GOTOFF does not need to be
  53    checked here.  I am not sure if some of the others are ever used with
  54    pcrel, but it is easier to be safe than sorry. */
  55
  56 #define TC_RELOC_RTSYM_LOC_FIXUP(FIX)  \
  57   ((FIX)->fx_r_type != BFD_RELOC_386_PLT32 \
  58    && (FIX)->fx_r_type != BFD_RELOC_386_GOT32 \
  59    && (FIX)->fx_r_type != BFD_RELOC_386_GOTPC)
  60
  61 #define TARGET_ARCH             bfd_arch_i386
  62 #define TARGET_BYTES_BIG_ENDIAN 0
  63
  64 #ifdef OBJ_AOUT
  65 #ifdef TE_NetBSD
  66 #define TARGET_FORMAT           "a.out-i386-netbsd"
  67 #endif
  68 #ifdef TE_386BSD
  69 #define TARGET_FORMAT           "a.out-i386-bsd"
  70 #endif
  71 #ifdef TE_LINUX
  72 #define TARGET_FORMAT           "a.out-i386-linux"
  73 #endif
  74 #ifdef TE_Mach
  75 #define TARGET_FORMAT           "a.out-mach3"
  76 #endif
  77 #ifndef TARGET_FORMAT
  78 #define TARGET_FORMAT           "a.out-i386"
  79 #endif
  80 #endif /* OBJ_AOUT */
  81
  82 #ifdef OBJ_ELF
  83 #define TARGET_FORMAT           "elf32-i386"
  84 #endif
  85
  86 #else /* ! BFD_ASSEMBLER */
  87
  88 /* COFF STUFF */
  89
  90 #define COFF_MAGIC I386MAGIC
  91 #define BFD_ARCH bfd_arch_i386
  92 #define COFF_FLAGS F_AR32WR
  93 #define TC_COUNT_RELOC(x) ((x)->fx_addsy /* ||(x)->fx_subsy||(x)->fx_offset */)
  94 #define TC_COFF_FIX2RTYPE(fixP) tc_coff_fix2rtype(fixP)
  95 extern short tc_coff_fix2rtype ();
  96 #define TC_COFF_SIZEMACHDEP(frag) tc_coff_sizemachdep(frag)
  97 extern int tc_coff_sizemachdep PARAMS ((fragS *frag));
  98 #define SUB_SEGMENT_ALIGN(SEG) 2
  99
 100 /* Need this for PIC relocations */
 101 #define NEED_FX_R_TYPE
 102
 103 #define AOUT_MACHTYPE 100
 104 #undef REVERSE_SORT_RELOCS
 105
 106 #endif /* ! BFD_ASSEMBLER */
 107
 108 #ifdef BFD_ASSEMBLER
 109 #define NO_RELOC BFD_RELOC_NONE
 110 #else
 111 #define NO_RELOC 0
 112 #endif
 113 #define tc_coff_symbol_emit_hook(a)     ;       /* not used */
 114
 115 #ifndef OBJ_AOUT
 116 /* Local labels starts with .L */
 117 #define LOCAL_LABEL(name) (name[0] == '.' \
 118                  && (name[1] == 'L' || name[1] == 'X' || name[1] == '.'))
 119 #define FAKE_LABEL_NAME ".L0\001"
 120 #endif
 121 #define LOCAL_LABELS_FB 1
 122
 123 #define tc_aout_pre_write_hook(x)       {;}     /* not used */
 124 #define tc_crawl_symbol_chain(a)        {;}     /* not used */
 125 #define tc_headers_hook(a)              {;}     /* not used */
 126
 127 #define MAX_OPERANDS 3          /* max operands per insn */
 128 #define MAX_PREFIXES 5          /* max prefixes per opcode */
 129 #define MAX_IMMEDIATE_OPERANDS 2/* max immediates per insn */
 130 #define MAX_MEMORY_OPERANDS 2   /* max memory ref per insn (lcall uses 2) */
 131
 132 /* we define the syntax here (modulo base,index,scale syntax) */
 133 #define REGISTER_PREFIX '%'
 134 #define IMMEDIATE_PREFIX '$'
 135 #define ABSOLUTE_PREFIX '*'
 136 #define PREFIX_SEPERATOR '/'
 137
 138 #define TWO_BYTE_OPCODE_ESCAPE 0x0f
 139 #define NOP_OPCODE (char) 0x90
 140
 141 /* register numbers */
 142 #define EBP_REG_NUM 5
 143 #define ESP_REG_NUM 4
 144
 145 /* modrm_byte.regmem for twobyte escape */
 146 #define ESCAPE_TO_TWO_BYTE_ADDRESSING ESP_REG_NUM
 147 /* index_base_byte.index for no index register addressing */
 148 #define NO_INDEX_REGISTER ESP_REG_NUM
 149 /* index_base_byte.base for no base register addressing */
 150 #define NO_BASE_REGISTER EBP_REG_NUM
 151
 152 /* these are the att as opcode suffixes, making movl --> mov, for example */
 153 #define DWORD_OPCODE_SUFFIX 'l'
 154 #define WORD_OPCODE_SUFFIX  'w'
 155 #define BYTE_OPCODE_SUFFIX  'b'
 156
 157 /* modrm.mode = REGMEM_FIELD_HAS_REG when a register is in there */
 158 #define REGMEM_FIELD_HAS_REG 0x3/* always = 0x3 */
 159 #define REGMEM_FIELD_HAS_MEM (~REGMEM_FIELD_HAS_REG)
 160
 161 #define END_OF_INSN '\0'
 162
 163 /*
 164   When an operand is read in it is classified by its type.  This type includes
 165   all the possible ways an operand can be used.  Thus, '%eax' is both 'register
 166   # 0' and 'The Accumulator'.  In our language this is expressed by OR'ing
 167   'Reg32' (any 32 bit register) and 'Acc' (the accumulator).
 168   Operands are classified so that we can match given operand types with
 169   the opcode table in i386-opcode.h.
 170   */
 171 #define Unknown 0x0
 172 /* register */
 173 #define Reg8    0x1             /* 8 bit reg */
 174 #define Reg16   0x2             /* 16 bit reg */
 175 #define Reg32   0x4             /* 32 bit reg */
 176 #define Reg     (Reg8|Reg16|Reg32)      /* gen'l register */
 177 #define WordReg (Reg16|Reg32)   /* for push/pop operands */
 178 /* immediate */
 179 #define Imm8    0x8             /* 8 bit immediate */
 180 #define Imm8S   0x10            /* 8 bit immediate sign extended */
 181 #define Imm16   0x20            /* 16 bit immediate */
 182 #define Imm32   0x40            /* 32 bit immediate */
 183 #define Imm1    0x80            /* 1 bit immediate */
 184 #define ImmUnknown Imm32        /* for unknown expressions */
 185 #define Imm     (Imm8|Imm8S|Imm16|Imm32)        /* gen'l immediate */
 186 /* memory */
 187 #define Disp8   0x200           /* 8 bit displacement (for jumps) */
 188 #define Disp16  0x400           /* 16 bit displacement */
 189 #define Disp32  0x800           /* 32 bit displacement */
 190 #define Disp    (Disp8|Disp16|Disp32)   /* General displacement */
 191 #define DispUnknown Disp32      /* for unknown size displacements */
 192 #define Mem8    0x1000
 193 #define Mem16   0x2000
 194 #define Mem32   0x4000
 195 #define BaseIndex 0x8000
 196 #define Mem     (Disp|Mem8|Mem16|Mem32|BaseIndex)       /* General memory */
 197 #define WordMem   (Mem16|Mem32|Disp|BaseIndex)
 198 #define ByteMem   (Mem8|Disp|BaseIndex)
 199 /* specials */
 200 #define InOutPortReg 0x10000    /* register to hold in/out port addr = dx */
 201 #define ShiftCount 0x20000      /* register to hold shift cound = cl */
 202 #define Control 0x40000         /* Control register */
 203 #define Debug   0x80000         /* Debug register */
 204 #define Test    0x100000        /* Test register */
 205 #define FloatReg 0x200000       /* Float register */
 206 #define FloatAcc 0x400000       /* Float stack top %st(0) */
 207 #define SReg2   0x800000        /* 2 bit segment register */
 208 #define SReg3   0x1000000       /* 3 bit segment register */
 209 #define Acc     0x2000000       /* Accumulator %al or %ax or %eax */
 210 #define ImplicitRegister (InOutPortReg|ShiftCount|Acc|FloatAcc)
 211 #define JumpAbsolute 0x4000000
 212 #define Abs8  0x08000000
 213 #define Abs16 0x10000000
 214 #define Abs32 0x20000000
 215 #define Abs (Abs8|Abs16|Abs32)
 216
 217 #define Byte (Reg8|Imm8|Imm8S)
 218 #define Word (Reg16|Imm16)
 219 #define DWord (Reg32|Imm32)
 220
 221 #define SMALLEST_DISP_TYPE(num) \
 222     fits_in_signed_byte(num) ? (Disp8|Disp32|Abs8|Abs32) : (Disp32|Abs32)
 223
 224 typedef struct
 225 {
 226   /* instruction name sans width suffix ("mov" for movl insns) */
 227   char *name;
 228
 229   /* how many operands */
 230   unsigned int operands;
 231
 232   /* base_opcode is the fundamental opcode byte with a optional prefix(es). */
 233   unsigned int base_opcode;
 234
 235   /* extension_opcode is the 3 bit extension for group <n> insns.
 236      If this template has no extension opcode (the usual case) use None */
 237   unsigned char extension_opcode;
 238 #define None 0xff               /* If no extension_opcode is possible. */
 239
 240   /* the bits in opcode_modifier are used to generate the final opcode from
 241      the base_opcode.  These bits also are used to detect alternate forms of
 242      the same instruction */
 243   unsigned int opcode_modifier;
 244
 245   /* opcode_modifier bits: */
 246 #define W        0x1            /* set if operands are words or dwords */
 247 #define D        0x2            /* D = 0 if Reg --> Regmem; D = 1 if Regmem --> Reg */
 248   /* direction flag for floating insns:  MUST BE 0x400 */
 249 #define FloatD 0x400
 250   /* shorthand */
 251 #define DW (D|W)
 252 #define ShortForm 0x10          /* register is in low 3 bits of opcode */
 253 #define ShortFormW 0x20         /* ShortForm and W bit is 0x8 */
 254 #define Seg2ShortForm 0x40      /* encoding of load segment reg insns */
 255 #define Seg3ShortForm 0x80      /* fs/gs segment register insns. */
 256 #define Jump 0x100              /* special case for jump insns. */
 257 #define JumpInterSegment 0x200  /* special case for intersegment leaps/calls */
 258   /* 0x400 CANNOT BE USED since it's already used by FloatD above */
 259 #define DONT_USE 0x400
 260 #define NoModrm 0x800
 261 #define Modrm 0x1000
 262 #define imulKludge 0x2000
 263 #define JumpByte 0x4000
 264 #define JumpDword 0x8000
 265 #define ReverseRegRegmem 0x10000
 266 #define Data16 0x20000          /* needs data prefix if in 32-bit mode */
 267 #define Data32 0x40000          /* needs data prefix if in 16-bit mode */
 268
 269   /* (opcode_modifier & COMES_IN_ALL_SIZES) is true if the
 270      instuction comes in byte, word, and dword sizes and is encoded into
 271      machine code in the canonical way. */
 272 #define COMES_IN_ALL_SIZES (W)
 273
 274   /* (opcode_modifier & COMES_IN_BOTH_DIRECTIONS) indicates that the
 275      source and destination operands can be reversed by setting either
 276      the D (for integer insns) or the FloatD (for floating insns) bit
 277      in base_opcode. */
 278 #define COMES_IN_BOTH_DIRECTIONS (D|FloatD)
 279
 280   /* operand_types[i] describes the type of operand i.  This is made
 281      by OR'ing together all of the possible type masks.  (e.g.
 282      'operand_types[i] = Reg|Imm' specifies that operand i can be
 283      either a register or an immediate operand */
 284   unsigned int operand_types[3];
 285 }
 286 template;
 287
 288 /*
 289   'templates' is for grouping together 'template' structures for opcodes
 290   of the same name.  This is only used for storing the insns in the grand
 291   ole hash table of insns.
 292   The templates themselves start at START and range up to (but not including)
 293   END.
 294   */
 295 typedef struct
 296   {
 297     template *start;
 298     template *end;
 299   } templates;
 300
 301 /* these are for register name --> number & type hash lookup */
 302 typedef struct
 303   {
 304     char *reg_name;
 305     unsigned int reg_type;
 306     unsigned int reg_num;
 307   }
 308
 309 reg_entry;
 310
 311 typedef struct
 312   {
 313     char *seg_name;
 314     unsigned int seg_prefix;
 315   }
 316
 317 seg_entry;
 318
 319 /* these are for prefix name --> prefix code hash lookup */
 320 typedef struct
 321   {
 322     char *prefix_name;
 323     unsigned char prefix_code;
 324   }
 325
 326 prefix_entry;
 327
 328 /* 386 operand encoding bytes:  see 386 book for details of this. */
 329 typedef struct
 330   {
 331     unsigned regmem:3;          /* codes register or memory operand */
 332     unsigned reg:3;             /* codes register operand (or extended opcode) */
 333     unsigned mode:2;            /* how to interpret regmem & reg */
 334   }
 335
 336 modrm_byte;
 337
 338 /* 386 opcode byte to code indirect addressing. */
 339 typedef struct
 340   {
 341     unsigned base:3;
 342     unsigned index:3;
 343     unsigned scale:2;
 344   }
 345
 346 base_index_byte;
 347
 348 /* The name of the global offset table generated by the compiler. Allow
 349    this to be overridden if need be. */
 350 #ifndef GLOBAL_OFFSET_TABLE_NAME
 351 #define GLOBAL_OFFSET_TABLE_NAME "_GLOBAL_OFFSET_TABLE_"
 352 #endif
 353
 354 #ifdef BFD_ASSEMBLER
 355 void i386_validate_fix ();
 356 #define TC_VALIDATE_FIX(FIXP,SEGTYPE,SKIP) i386_validate_fix(FIXP)
 357 #endif
 358
 359 #endif /* TC_I386 */
 360
 361 #define md_operand(x)
 362
 363 extern const struct relax_type md_relax_table[];
 364 #define TC_GENERIC_RELAX_TABLE md_relax_table
 365
 366 /* end of tc-i386.h */