gas/config/tc-arm.h

   1 /* This file is tc-arm.h
   2    Copyright (C) 1994-2014 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 #endif
 120
 121 /* NOTE: The fake label creation in stabs.c:s_stab_generic() has
 122    deliberately not been updated to mark assembler created stabs
 123    symbols as Thumb.  */
 124
 125 #define TC_FIX_TYPE int
 126 #define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)
 127
 128 /* We need to keep some local information on symbols.  */
 129
 130 #define TC_SYMFIELD_TYPE        unsigned int
 131 #define ARM_GET_FLAG(s)         (*symbol_get_tc (s))
 132 #define ARM_SET_FLAG(s,v)       (*symbol_get_tc (s) |= (v))
 133 #define ARM_RESET_FLAG(s,v)     (*symbol_get_tc (s) &= ~(v))
 134
 135 #define ARM_FLAG_THUMB          (1 << 0)        /* The symbol is a Thumb symbol rather than an Arm symbol.  */
 136 #define ARM_FLAG_INTERWORK      (1 << 1)        /* The symbol is attached to code that supports interworking.  */
 137 #define THUMB_FLAG_FUNC         (1 << 2)        /* The symbol is attached to the start of a Thumb function.  */
 138
 139 #define ARM_IS_THUMB(s)         (ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
 140 #define ARM_IS_INTERWORK(s)     (ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)
 141
 142 #ifdef OBJ_ELF
 143
 144 /* For ELF objects THUMB_IS_FUNC is inferred from
 145    ARM_IS_THUMB and the function type.  */
 146 #define THUMB_IS_FUNC(s)                                        \
 147   ((s) != NULL                                                  \
 148    && ((arm_is_eabi ()                                          \
 149         && (ARM_IS_THUMB (s))                                   \
 150         && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))       \
 151        || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))
 152
 153 #define ARM_IS_FUNC(s)                                  \
 154   (((s) != NULL                                         \
 155     && arm_is_eabi ()                                   \
 156     && !(ARM_IS_THUMB (s))                              \
 157     /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */    \
 158     && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))
 159
 160
 161 #else
 162
 163 #define THUMB_IS_FUNC(s)        ((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
 164 #define ARM_IS_FUNC(s)          (!THUMB_IS_FUNC (s) \
 165                                  && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
 166 #endif
 167
 168 #define ARM_SET_THUMB(s,t)      ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB)     : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
 169 #define ARM_SET_INTERWORK(s,t)  ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
 170 #define THUMB_SET_FUNC(s,t)     ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC)    : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))
 171
 172 void arm_copy_symbol_attributes (symbolS *, symbolS *);
 173
 174 #ifndef TC_COPY_SYMBOL_ATTRIBUTES
 175 #define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
 176   (arm_copy_symbol_attributes (DEST, SRC))
 177 #endif
 178
 179 #define TC_START_LABEL(C,S,STR)            (C == ':' || (C == '/' && arm_data_in_code ()))
 180 #define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
 181 #define obj_adjust_symtab()              arm_adjust_symtab ()
 182
 183 #define LISTING_HEADER "ARM GAS "
 184
 185 #define OPTIONAL_REGISTER_PREFIX '%'
 186
 187 #define LOCAL_LABEL(name)  (name[0] == '.' && name[1] == 'L')
 188 #define LOCAL_LABELS_FB    1
 189
 190 /* This expression evaluates to true if the relocation is for a local
 191    object for which we still want to do the relocation at runtime.
 192    False if we are willing to perform this relocation while building
 193    the .o file.  GOTOFF does not need to be checked here because it is
 194    not pcrel.  I am not sure if some of the others are ever used with
 195    pcrel, but it is easier to be safe than sorry.  */
 196
 197 #define TC_FORCE_RELOCATION_LOCAL(FIX)                  \
 198   (!(FIX)->fx_pcrel                                     \
 199    || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32           \
 200    || (FIX)->fx_r_type == BFD_RELOC_32                  \
 201    || ((FIX)->fx_addsy != NULL && S_IS_WEAK ((FIX)->fx_addsy))  \
 202    || TC_FORCE_RELOCATION (FIX))
 203
 204 /* Force output of R_ARM_REL32 relocations against thumb function symbols.
 205    This is needed to ensure the low bit is handled correctly.  */
 206 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG)  \
 207   (THUMB_IS_FUNC ((FIX)->fx_addsy)              \
 208    || !SEG_NORMAL (SEG))
 209
 210 #define TC_FORCE_RELOCATION_ABS(FIX)                    \
 211   (((FIX)->fx_pcrel                                     \
 212     && (FIX)->fx_r_type != BFD_RELOC_32                 \
 213     && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32)         \
 214    || TC_FORCE_RELOCATION(FIX))
 215
 216 #define TC_CONS_FIX_NEW cons_fix_new_arm
 217
 218 #define MAX_MEM_ALIGNMENT_BYTES    6
 219 #define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)
 220
 221 /* For frags in code sections we need to record whether they contain
 222    ARM code or THUMB code.  This is that if they have to be aligned,
 223    they can contain the correct type of no-op instruction.  */
 224 struct arm_frag_type
 225 {
 226   int thumb_mode;
 227 #ifdef OBJ_ELF
 228   /* If there is a mapping symbol at offset 0 in this frag,
 229      it will be saved in FIRST_MAP.  If there are any mapping
 230      symbols in this frag, the last one will be saved in
 231      LAST_MAP.  */
 232   symbolS *first_map, *last_map;
 233 #endif
 234 };
 235
 236 #define TC_FRAG_TYPE            struct arm_frag_type
 237 /* NOTE: max_chars is a local variable from frag_var / frag_variant.  */
 238 #define TC_FRAG_INIT(fragp)     arm_init_frag (fragp, max_chars)
 239 #define HANDLE_ALIGN(fragp)     arm_handle_align (fragp)
 240
 241 #define md_do_align(N, FILL, LEN, MAX, LABEL)                                   \
 242   if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg))     \
 243     {                                                                           \
 244       arm_frag_align_code (N, MAX);                                             \
 245       goto LABEL;                                                               \
 246     }
 247
 248 #define DWARF2_LINE_MIN_INSN_LENGTH     2
 249
 250 /* The lr register is r14.  */
 251 #define DWARF2_DEFAULT_RETURN_COLUMN  14
 252
 253 /* Registers are generally saved at negative offsets to the CFA.  */
 254 #define DWARF2_CIE_DATA_ALIGNMENT     (-4)
 255
 256 /* State variables for IT block handling.  */
 257 enum it_state
 258 {
 259   OUTSIDE_IT_BLOCK, MANUAL_IT_BLOCK, AUTOMATIC_IT_BLOCK
 260 };
 261 struct current_it
 262 {
 263   int mask;
 264   enum it_state state;
 265   int cc;
 266   int block_length;
 267   char *insn;
 268   int state_handled;
 269   int warn_deprecated;
 270   int insn_cond;
 271 };
 272
 273 #ifdef OBJ_ELF
 274 # define obj_frob_symbol(sym, punt)     armelf_frob_symbol ((sym), & (punt))
 275 # define md_elf_section_change_hook()   arm_elf_change_section ()
 276 # define md_elf_section_type(str, len)  arm_elf_section_type (str, len)
 277 # define GLOBAL_OFFSET_TABLE_NAME       "_GLOBAL_OFFSET_TABLE_"
 278 # define TC_SEGMENT_INFO_TYPE           struct arm_segment_info_type
 279
 280 /* This is not really an alignment operation, but it's something we
 281    need to do at the same time: whenever we are figuring out the
 282    alignment for data, we should check whether a $d symbol is
 283    necessary.  */
 284 # define md_cons_align(nbytes)          mapping_state (MAP_DATA)
 285
 286 enum mstate
 287 {
 288   MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections.  */
 289   MAP_DATA,
 290   MAP_ARM,
 291   MAP_THUMB
 292 };
 293
 294 void mapping_state (enum mstate);
 295
 296 struct arm_segment_info_type
 297 {
 298   enum mstate mapstate;
 299
 300   /* Bit N indicates that an R_ARM_NONE relocation has been output for
 301      __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
 302      emitted only once per section, to save unnecessary bloat.  */
 303   unsigned int marked_pr_dependency;
 304
 305   struct current_it current_it;
 306 };
 307
 308 /* We want .cfi_* pseudo-ops for generating unwind info.  */
 309 #define TARGET_USE_CFIPOP              1
 310
 311 /* CFI hooks.  */
 312 #define tc_regname_to_dw2regnum            tc_arm_regname_to_dw2regnum
 313 #define tc_cfi_frame_initial_instructions  tc_arm_frame_initial_instructions
 314
 315 #else /* Not OBJ_ELF.  */
 316 #define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
 317 #endif
 318
 319 #if defined OBJ_ELF || defined OBJ_COFF
 320
 321 # define EXTERN_FORCE_RELOC                     1
 322 # define tc_fix_adjustable(FIX)                 arm_fix_adjustable (FIX)
 323 #endif
 324
 325 #ifdef OBJ_ELF
 326 /* Values passed to md_apply_fix don't include the symbol value.  */
 327 # define MD_APPLY_SYM_VALUE(FIX)                arm_apply_sym_value (FIX)
 328 #endif
 329
 330 #ifdef OBJ_COFF
 331 # define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL)   arm_validate_fix (FIX)
 332 /* Values passed to md_apply_fix don't include the symbol value.  */
 333 # define MD_APPLY_SYM_VALUE(FIX)                0
 334 #endif
 335
 336 #define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)
 337
 338 extern long md_pcrel_from_section (struct fix *, segT);
 339 extern void arm_frag_align_code (int, int);
 340 extern void arm_validate_fix (struct fix *);
 341 extern const char * elf32_arm_target_format (void);
 342 extern void arm_elf_change_section (void);
 343 extern int arm_force_relocation (struct fix *);
 344 extern void arm_cleanup (void);
 345 extern void arm_start_line_hook (void);
 346 extern void arm_frob_label (symbolS *);
 347 extern int arm_data_in_code (void);
 348 extern char * arm_canonicalize_symbol_name (char *);
 349 extern void arm_adjust_symtab (void);
 350 extern void armelf_frob_symbol (symbolS *, int *);
 351 extern void cons_fix_new_arm (fragS *, int, int, expressionS *,
 352                               bfd_reloc_code_real_type);
 353 extern void arm_init_frag (struct frag *, int);
 354 extern void arm_handle_align (struct frag *);
 355 extern bfd_boolean arm_fix_adjustable (struct fix *);
 356 extern int arm_elf_section_type (const char *, size_t);
 357 extern int tc_arm_regname_to_dw2regnum (char *regname);
 358 extern void tc_arm_frame_initial_instructions (void);
 359
 360 #ifdef TE_PE
 361
 362 #define O_secrel O_md1
 363
 364 #define TC_DWARF2_EMIT_OFFSET  tc_pe_dwarf2_emit_offset
 365 void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);
 366
 367 #endif /* TE_PE */
 368
 369 #ifdef OBJ_ELF
 370 #define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
 371 extern int arm_convert_symbolic_attribute (const char *);
 372 extern int arm_apply_sym_value (struct fix *);
 373 #endif
 374
 375 #define tc_comment_chars arm_comment_chars
 376 extern char arm_comment_chars[];
 377
 378 #define tc_line_separator_chars arm_line_separator_chars
 379 extern char arm_line_separator_chars[];