gas/config/tc-arm.h

   1 /* This file is tc-arm.h
   2    Copyright (C) 1994-2015 Free Software Foundation, Inc.
   3    Contributed by Richard Earnshaw (rwe@pegasus.esprit.ec.org)
   4         Modified by David Taylor (dtaylor@armltd.co.uk)
   5
   6    This file is part of GAS, the GNU Assembler.
   7
   8    GAS is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3, or (at your option)
  11    any later version.
  12
  13    GAS is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GAS; see the file COPYING.  If not, write to the Free
  20    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  21    02110-1301, USA.  */
  22
  23 #define TC_ARM 1
  24
  25 #ifndef TARGET_BYTES_BIG_ENDIAN
  26 #define TARGET_BYTES_BIG_ENDIAN 0
  27 #endif
  28
  29 #define WORKING_DOT_WORD
  30
  31 #define COFF_MAGIC      ARMMAGIC
  32 #define TARGET_ARCH     bfd_arch_arm
  33
  34 #define DIFF_EXPR_OK
  35
  36 #ifdef  LITTLE_ENDIAN
  37 #undef  LITTLE_ENDIAN
  38 #endif
  39
  40 #ifdef  BIG_ENDIAN
  41 #undef  BIG_ENDIAN
  42 #endif
  43
  44 #define LITTLE_ENDIAN   1234
  45 #define BIG_ENDIAN      4321
  46
  47 struct fix;
  48
  49 #if defined OBJ_AOUT
  50 # if defined TE_RISCIX
  51 #  define TARGET_FORMAT "a.out-riscix"
  52 # elif defined TE_LINUX
  53 #  define ARM_BI_ENDIAN
  54 #  define TARGET_FORMAT "a.out-arm-linux"
  55 # elif defined TE_NetBSD
  56 #  define TARGET_FORMAT "a.out-arm-netbsd"
  57 # else
  58 #  define ARM_BI_ENDIAN
  59 #  define TARGET_FORMAT (target_big_endian ? "a.out-arm-big" : "a.out-arm-little")
  60 # endif
  61 #elif defined OBJ_AIF
  62 # define TARGET_FORMAT "aif"
  63 #elif defined OBJ_COFF
  64 # define ARM_BI_ENDIAN
  65 # if defined TE_PE
  66 #  if defined TE_EPOC
  67 #   define TARGET_FORMAT (target_big_endian ? "epoc-pe-arm-big" : "epoc-pe-arm-little")
  68 #  elif defined TE_WINCE
  69 #   define TARGET_FORMAT (target_big_endian ? "pe-arm-wince-big" : "pe-arm-wince-little")
  70 #  else
  71 #   define TARGET_FORMAT (target_big_endian ? "pe-arm-big" : "pe-arm-little")
  72 #  endif
  73 # else
  74 #  define TARGET_FORMAT (target_big_endian ? "coff-arm-big" : "coff-arm-little")
  75 # endif
  76 #elif defined OBJ_ELF
  77 # define ARM_BI_ENDIAN
  78 # define TARGET_FORMAT  elf32_arm_target_format ()
  79 #endif
  80
  81 /* We support double slash line-comments for compatibility with the ARM AArch64 Assembler.  */
  82 #define DOUBLESLASH_LINE_COMMENTS
  83
  84 /* We conditionally support labels without a colon.  */
  85 #define LABELS_WITHOUT_COLONS codecomposer_syntax
  86 extern bfd_boolean codecomposer_syntax;
  87
  88 #define tc_symbol_chars arm_symbol_chars
  89 extern const char arm_symbol_chars[];
  90
  91 #define TC_FORCE_RELOCATION(FIX) arm_force_relocation (FIX)
  92
  93 extern unsigned int arm_frag_max_var (struct frag *);
  94 #define md_frag_max_var arm_frag_max_var
  95
  96 #define md_relax_frag(segment, fragp, stretch) \
  97   arm_relax_frag (segment, fragp, stretch)
  98 extern int arm_relax_frag (asection *, struct frag *, long);
  99
 100 #define md_optimize_expr(l,o,r)         arm_optimize_expr (l, o, r)
 101 extern int arm_optimize_expr (expressionS *, operatorT, expressionS *);
 102
 103 #define md_cleanup() arm_cleanup ()
 104
 105 #define md_start_line_hook() arm_start_line_hook ()
 106
 107 #define TC_START_LABEL_WITHOUT_COLON(c, l)  tc_start_label_without_colon (c, l)
 108 extern bfd_boolean tc_start_label_without_colon (char, const char *);
 109
 110 #define tc_frob_label(S) arm_frob_label (S)
 111
 112 /* We also need to mark assembler created symbols:  */
 113 #define tc_frob_fake_label(S) arm_frob_label (S)
 114
 115 #ifdef OBJ_ELF
 116 #define md_end arm_md_end
 117 extern void arm_md_end (void);
 118 bfd_boolean arm_is_eabi (void);
 119
 120 #define md_post_relax_hook              aeabi_set_public_attributes ()
 121 extern void aeabi_set_public_attributes (void);
 122 #endif
 123
 124 /* NOTE: The fake label creation in stabs.c:s_stab_generic() has
 125    deliberately not been updated to mark assembler created stabs
 126    symbols as Thumb.  */
 127
 128 #define TC_FIX_TYPE int
 129 #define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)
 130
 131 /* We need to keep some local information on symbols.  */
 132
 133 #define TC_SYMFIELD_TYPE        unsigned int
 134 #define ARM_GET_FLAG(s)         (*symbol_get_tc (s))
 135 #define ARM_SET_FLAG(s,v)       (*symbol_get_tc (s) |= (v))
 136 #define ARM_RESET_FLAG(s,v)     (*symbol_get_tc (s) &= ~(v))
 137
 138 #define ARM_FLAG_THUMB          (1 << 0)        /* The symbol is a Thumb symbol rather than an Arm symbol.  */
 139 #define ARM_FLAG_INTERWORK      (1 << 1)        /* The symbol is attached to code that supports interworking.  */
 140 #define THUMB_FLAG_FUNC         (1 << 2)        /* The symbol is attached to the start of a Thumb function.  */
 141
 142 #define ARM_IS_THUMB(s)         (ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
 143 #define ARM_IS_INTERWORK(s)     (ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)
 144
 145 #ifdef OBJ_ELF
 146
 147 /* For ELF objects THUMB_IS_FUNC is inferred from
 148    ARM_IS_THUMB and the function type.  */
 149 #define THUMB_IS_FUNC(s)                                        \
 150   ((s) != NULL                                                  \
 151    && ((arm_is_eabi ()                                          \
 152         && (ARM_IS_THUMB (s))                                   \
 153         && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))       \
 154        || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))
 155
 156 #define ARM_IS_FUNC(s)                                  \
 157   (((s) != NULL                                         \
 158     && arm_is_eabi ()                                   \
 159     && !(ARM_IS_THUMB (s))                              \
 160     /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */    \
 161     && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))
 162
 163
 164 #else
 165
 166 #define THUMB_IS_FUNC(s)        ((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
 167 #define ARM_IS_FUNC(s)          (!THUMB_IS_FUNC (s) \
 168                                  && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
 169 #endif
 170
 171 #define ARM_SET_THUMB(s,t)      ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB)     : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
 172 #define ARM_SET_INTERWORK(s,t)  ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
 173 #define THUMB_SET_FUNC(s,t)     ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC)    : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))
 174
 175 void arm_copy_symbol_attributes (symbolS *, symbolS *);
 176
 177 #ifndef TC_COPY_SYMBOL_ATTRIBUTES
 178 #define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
 179   (arm_copy_symbol_attributes (DEST, SRC))
 180 #endif
 181
 182 #define TC_START_LABEL(C,S,STR)            (C == ':' || (C == '/' && arm_data_in_code ()))
 183 #define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
 184 #define obj_adjust_symtab()              arm_adjust_symtab ()
 185
 186 #define LISTING_HEADER "ARM GAS "
 187
 188 #define OPTIONAL_REGISTER_PREFIX '%'
 189
 190 #define LOCAL_LABEL(name)  (name[0] == '.' && name[1] == 'L')
 191 #define LOCAL_LABELS_FB    1
 192
 193 /* This expression evaluates to true if the relocation is for a local
 194    object for which we still want to do the relocation at runtime.
 195    False if we are willing to perform this relocation while building
 196    the .o file.  GOTOFF does not need to be checked here because it is
 197    not pcrel.  I am not sure if some of the others are ever used with
 198    pcrel, but it is easier to be safe than sorry.  */
 199
 200 #define TC_FORCE_RELOCATION_LOCAL(FIX)                  \
 201   (!(FIX)->fx_pcrel                                     \
 202    || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32           \
 203    || (FIX)->fx_r_type == BFD_RELOC_32                  \
 204    || ((FIX)->fx_addsy != NULL && S_IS_WEAK ((FIX)->fx_addsy))  \
 205    || TC_FORCE_RELOCATION (FIX))
 206
 207 /* Force output of R_ARM_REL32 relocations against thumb function symbols.
 208    This is needed to ensure the low bit is handled correctly.  */
 209 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG)  \
 210   (THUMB_IS_FUNC ((FIX)->fx_addsy)              \
 211    || !SEG_NORMAL (SEG))
 212
 213 #define TC_FORCE_RELOCATION_ABS(FIX)                    \
 214   (((FIX)->fx_pcrel                                     \
 215     && (FIX)->fx_r_type != BFD_RELOC_32                 \
 216     && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32)         \
 217    || TC_FORCE_RELOCATION(FIX))
 218
 219 #define TC_CONS_FIX_NEW cons_fix_new_arm
 220
 221 #define MAX_MEM_ALIGNMENT_BYTES    6
 222 #define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)
 223
 224 /* For frags in code sections we need to record whether they contain
 225    ARM code or THUMB code.  This is that if they have to be aligned,
 226    they can contain the correct type of no-op instruction.  */
 227 struct arm_frag_type
 228 {
 229   int thumb_mode;
 230 #ifdef OBJ_ELF
 231   /* If there is a mapping symbol at offset 0 in this frag,
 232      it will be saved in FIRST_MAP.  If there are any mapping
 233      symbols in this frag, the last one will be saved in
 234      LAST_MAP.  */
 235   symbolS *first_map, *last_map;
 236 #endif
 237 };
 238
 239 static inline int
 240 arm_min (int am_p1, int am_p2)
 241 {
 242   return am_p1 < am_p2 ? am_p1 : am_p2;
 243 }
 244
 245 #define TC_FRAG_TYPE            struct arm_frag_type
 246 /* NOTE: max_chars is a local variable from frag_var / frag_variant.  */
 247 #define TC_FRAG_INIT(fragp)     arm_init_frag (fragp, max_chars)
 248 #define HANDLE_ALIGN(fragp)     arm_handle_align (fragp)
 249 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN)                 \
 250   ((!(FRCHAIN)->frch_next && subseg_text_p (SEG))               \
 251    ? arm_min (2, get_recorded_alignment (SEG)) : 0)
 252
 253 #define md_do_align(N, FILL, LEN, MAX, LABEL)                                   \
 254   if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg))     \
 255     {                                                                           \
 256       arm_frag_align_code (N, MAX);                                             \
 257       goto LABEL;                                                               \
 258     }
 259
 260 #define DWARF2_LINE_MIN_INSN_LENGTH     2
 261
 262 /* The lr register is r14.  */
 263 #define DWARF2_DEFAULT_RETURN_COLUMN  14
 264
 265 /* Registers are generally saved at negative offsets to the CFA.  */
 266 #define DWARF2_CIE_DATA_ALIGNMENT     (-4)
 267
 268 /* State variables for IT block handling.  */
 269 enum it_state
 270 {
 271   OUTSIDE_IT_BLOCK, MANUAL_IT_BLOCK, AUTOMATIC_IT_BLOCK
 272 };
 273 struct current_it
 274 {
 275   int mask;
 276   enum it_state state;
 277   int cc;
 278   int block_length;
 279   char *insn;
 280   int state_handled;
 281   int warn_deprecated;
 282   int insn_cond;
 283 };
 284
 285 #ifdef OBJ_ELF
 286 # define obj_frob_symbol(sym, punt)     armelf_frob_symbol ((sym), & (punt))
 287 # define md_elf_section_change_hook()   arm_elf_change_section ()
 288 # define md_elf_section_type(str, len)  arm_elf_section_type (str, len)
 289 # define GLOBAL_OFFSET_TABLE_NAME       "_GLOBAL_OFFSET_TABLE_"
 290 # define TC_SEGMENT_INFO_TYPE           struct arm_segment_info_type
 291
 292 /* This is not really an alignment operation, but it's something we
 293    need to do at the same time: whenever we are figuring out the
 294    alignment for data, we should check whether a $d symbol is
 295    necessary.  */
 296 # define md_cons_align(nbytes)          mapping_state (MAP_DATA)
 297
 298 enum mstate
 299 {
 300   MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections.  */
 301   MAP_DATA,
 302   MAP_ARM,
 303   MAP_THUMB
 304 };
 305
 306 void mapping_state (enum mstate);
 307
 308 struct arm_segment_info_type
 309 {
 310   enum mstate mapstate;
 311
 312   /* Bit N indicates that an R_ARM_NONE relocation has been output for
 313      __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
 314      emitted only once per section, to save unnecessary bloat.  */
 315   unsigned int marked_pr_dependency;
 316
 317   struct current_it current_it;
 318 };
 319
 320 /* We want .cfi_* pseudo-ops for generating unwind info.  */
 321 #define TARGET_USE_CFIPOP              1
 322
 323 /* CFI hooks.  */
 324 #define tc_regname_to_dw2regnum            tc_arm_regname_to_dw2regnum
 325 #define tc_cfi_frame_initial_instructions  tc_arm_frame_initial_instructions
 326
 327 #else /* Not OBJ_ELF.  */
 328 #define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
 329 #endif
 330
 331 #if defined OBJ_ELF || defined OBJ_COFF
 332
 333 # define EXTERN_FORCE_RELOC                     1
 334 # define tc_fix_adjustable(FIX)                 arm_fix_adjustable (FIX)
 335 #endif
 336
 337 #ifdef OBJ_ELF
 338 /* Values passed to md_apply_fix don't include the symbol value.  */
 339 # define MD_APPLY_SYM_VALUE(FIX)                arm_apply_sym_value (FIX, this_segment)
 340 #endif
 341
 342 #ifdef OBJ_COFF
 343 # define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL)   arm_validate_fix (FIX)
 344 /* Values passed to md_apply_fix don't include the symbol value.  */
 345 # define MD_APPLY_SYM_VALUE(FIX)                0
 346 #endif
 347
 348 #define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)
 349
 350 extern long md_pcrel_from_section (struct fix *, segT);
 351 extern void arm_frag_align_code (int, int);
 352 extern void arm_validate_fix (struct fix *);
 353 extern const char * elf32_arm_target_format (void);
 354 extern void arm_elf_change_section (void);
 355 extern int arm_force_relocation (struct fix *);
 356 extern void arm_cleanup (void);
 357 extern void arm_start_line_hook (void);
 358 extern void arm_frob_label (symbolS *);
 359 extern int arm_data_in_code (void);
 360 extern char * arm_canonicalize_symbol_name (char *);
 361 extern void arm_adjust_symtab (void);
 362 extern void armelf_frob_symbol (symbolS *, int *);
 363 extern void cons_fix_new_arm (fragS *, int, int, expressionS *,
 364                               bfd_reloc_code_real_type);
 365 extern void arm_init_frag (struct frag *, int);
 366 extern void arm_handle_align (struct frag *);
 367 extern bfd_boolean arm_fix_adjustable (struct fix *);
 368 extern int arm_elf_section_type (const char *, size_t);
 369 extern int tc_arm_regname_to_dw2regnum (char *regname);
 370 extern void tc_arm_frame_initial_instructions (void);
 371
 372 #ifdef TE_PE
 373
 374 #define O_secrel O_md1
 375
 376 #define TC_DWARF2_EMIT_OFFSET  tc_pe_dwarf2_emit_offset
 377 void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);
 378
 379 #endif /* TE_PE */
 380
 381 #ifdef OBJ_ELF
 382 #define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
 383 extern int arm_convert_symbolic_attribute (const char *);
 384 extern int arm_apply_sym_value (struct fix *, segT);
 385 #endif
 386
 387 #define tc_comment_chars arm_comment_chars
 388 extern char arm_comment_chars[];
 389
 390 #define tc_line_separator_chars arm_line_separator_chars
 391 extern char arm_line_separator_chars[];
 392
 393 #define TC_EQUAL_IN_INSN(c, s) arm_tc_equal_in_insn ((c), (s))
 394 extern bfd_boolean arm_tc_equal_in_insn (int, char *);