gas/config/tc-arm.h

   1 /* This file is tc-arm.h
   2    Copyright (C) 1994-2016 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(NUL_CHAR, NEXT_CHAR) \
 108   tc_start_label_without_colon ()
 109 extern bfd_boolean tc_start_label_without_colon (void);
 110
 111 #define tc_frob_label(S) arm_frob_label (S)
 112
 113 /* We also need to mark assembler created symbols:  */
 114 #define tc_frob_fake_label(S) arm_frob_label (S)
 115
 116 #ifdef OBJ_ELF
 117 #define md_elf_section_letter arm_elf_section_letter
 118 extern bfd_vma arm_elf_section_letter (int, char **);
 119
 120 #define md_end arm_md_end
 121 extern void arm_md_end (void);
 122 bfd_boolean arm_is_eabi (void);
 123
 124 #define md_post_relax_hook              aeabi_set_public_attributes ()
 125 extern void aeabi_set_public_attributes (void);
 126 #endif
 127
 128 /* NOTE: The fake label creation in stabs.c:s_stab_generic() has
 129    deliberately not been updated to mark assembler created stabs
 130    symbols as Thumb.  */
 131
 132 #define TC_FIX_TYPE int
 133 #define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)
 134
 135 /* We need to keep some local information on symbols.  */
 136
 137 #define TC_SYMFIELD_TYPE        unsigned int
 138 #define ARM_GET_FLAG(s)         (*symbol_get_tc (s))
 139 #define ARM_SET_FLAG(s,v)       (*symbol_get_tc (s) |= (v))
 140 #define ARM_RESET_FLAG(s,v)     (*symbol_get_tc (s) &= ~(v))
 141
 142 #define ARM_FLAG_THUMB          (1 << 0)        /* The symbol is a Thumb symbol rather than an Arm symbol.  */
 143 #define ARM_FLAG_INTERWORK      (1 << 1)        /* The symbol is attached to code that supports interworking.  */
 144 #define THUMB_FLAG_FUNC         (1 << 2)        /* The symbol is attached to the start of a Thumb function.  */
 145
 146 #define ARM_IS_THUMB(s)         (ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
 147 #define ARM_IS_INTERWORK(s)     (ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)
 148
 149 #ifdef OBJ_ELF
 150
 151 /* For ELF objects THUMB_IS_FUNC is inferred from
 152    ARM_IS_THUMB and the function type.  */
 153 #define THUMB_IS_FUNC(s)                                        \
 154   ((s) != NULL                                                  \
 155    && ((arm_is_eabi ()                                          \
 156         && (ARM_IS_THUMB (s))                                   \
 157         && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))       \
 158        || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))
 159
 160 #define ARM_IS_FUNC(s)                                  \
 161   (((s) != NULL                                         \
 162     && arm_is_eabi ()                                   \
 163     && !(ARM_IS_THUMB (s))                              \
 164     /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */    \
 165     && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))
 166
 167
 168 #else
 169
 170 #define THUMB_IS_FUNC(s)        ((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
 171 #define ARM_IS_FUNC(s)          (!THUMB_IS_FUNC (s) \
 172                                  && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
 173 #endif
 174
 175 #define ARM_SET_THUMB(s,t)      ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB)     : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
 176 #define ARM_SET_INTERWORK(s,t)  ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
 177 #define THUMB_SET_FUNC(s,t)     ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC)    : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))
 178
 179 void arm_copy_symbol_attributes (symbolS *, symbolS *);
 180
 181 #ifndef TC_COPY_SYMBOL_ATTRIBUTES
 182 #define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
 183   (arm_copy_symbol_attributes (DEST, SRC))
 184 #endif
 185
 186 #define TC_START_LABEL(STR, NUL_CHAR, NEXT_CHAR)                        \
 187   (NEXT_CHAR == ':' || (NEXT_CHAR == '/' && arm_data_in_code ()))
 188 #define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
 189 #define obj_adjust_symtab()              arm_adjust_symtab ()
 190
 191 #define LISTING_HEADER "ARM GAS "
 192
 193 #define OPTIONAL_REGISTER_PREFIX '%'
 194
 195 #define LOCAL_LABEL(name)  (name[0] == '.' && name[1] == 'L')
 196 #define LOCAL_LABELS_FB    1
 197
 198 /* This expression evaluates to true if the relocation is for a local
 199    object for which we still want to do the relocation at runtime.
 200    False if we are willing to perform this relocation while building
 201    the .o file.  GOTOFF does not need to be checked here because it is
 202    not pcrel.  I am not sure if some of the others are ever used with
 203    pcrel, but it is easier to be safe than sorry.  */
 204
 205 #define TC_FORCE_RELOCATION_LOCAL(FIX)                  \
 206   (!(FIX)->fx_pcrel                                     \
 207    || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32           \
 208    || (FIX)->fx_r_type == BFD_RELOC_32                  \
 209    || ((FIX)->fx_addsy != NULL && S_IS_WEAK ((FIX)->fx_addsy))  \
 210    || TC_FORCE_RELOCATION (FIX))
 211
 212 /* Force output of R_ARM_REL32 relocations against thumb function symbols.
 213    This is needed to ensure the low bit is handled correctly.  */
 214 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG)  \
 215   (THUMB_IS_FUNC ((FIX)->fx_addsy)              \
 216    || !SEG_NORMAL (SEG))
 217
 218 #define TC_FORCE_RELOCATION_ABS(FIX)                    \
 219   (((FIX)->fx_pcrel                                     \
 220     && (FIX)->fx_r_type != BFD_RELOC_32                 \
 221     && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32)         \
 222    || TC_FORCE_RELOCATION(FIX))
 223
 224 #define TC_CONS_FIX_NEW cons_fix_new_arm
 225
 226 #define MAX_MEM_ALIGNMENT_BYTES    6
 227 #define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)
 228
 229 /* For frags in code sections we need to record whether they contain
 230    ARM code or THUMB code.  This is that if they have to be aligned,
 231    they can contain the correct type of no-op instruction.  */
 232 struct arm_frag_type
 233 {
 234   int thumb_mode;
 235 #ifdef OBJ_ELF
 236   /* If there is a mapping symbol at offset 0 in this frag,
 237      it will be saved in FIRST_MAP.  If there are any mapping
 238      symbols in this frag, the last one will be saved in
 239      LAST_MAP.  */
 240   symbolS *first_map, *last_map;
 241 #endif
 242 };
 243
 244 static inline int
 245 arm_min (int am_p1, int am_p2)
 246 {
 247   return am_p1 < am_p2 ? am_p1 : am_p2;
 248 }
 249
 250 #define TC_FRAG_TYPE            struct arm_frag_type
 251 /* NOTE: max_chars is a local variable from frag_var / frag_variant.  */
 252 #define TC_FRAG_INIT(fragp)     arm_init_frag (fragp, max_chars)
 253 #define TC_ALIGN_ZERO_IS_DEFAULT 1
 254 #define HANDLE_ALIGN(fragp)     arm_handle_align (fragp)
 255 /* PR gas/19276: COFF/PE segment alignment is already handled in coff_frob_section().  */
 256 #ifndef TE_PE
 257 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN)                         \
 258   ((!(FRCHAIN)->frch_next && subseg_text_p (SEG))               \
 259    ? arm_min (2, get_recorded_alignment (SEG)) : 0)
 260 #endif
 261
 262 #define md_do_align(N, FILL, LEN, MAX, LABEL)                                   \
 263   if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg))     \
 264     {                                                                           \
 265       arm_frag_align_code (N, MAX);                                             \
 266       goto LABEL;                                                               \
 267     }
 268
 269 #define DWARF2_LINE_MIN_INSN_LENGTH     2
 270
 271 /* The lr register is r14.  */
 272 #define DWARF2_DEFAULT_RETURN_COLUMN  14
 273
 274 /* Registers are generally saved at negative offsets to the CFA.  */
 275 #define DWARF2_CIE_DATA_ALIGNMENT     (-4)
 276
 277 /* State variables for IT block handling.  */
 278 enum it_state
 279 {
 280   OUTSIDE_IT_BLOCK, MANUAL_IT_BLOCK, AUTOMATIC_IT_BLOCK
 281 };
 282 struct current_it
 283 {
 284   int mask;
 285   enum it_state state;
 286   int cc;
 287   int block_length;
 288   char *insn;
 289   int state_handled;
 290   int warn_deprecated;
 291   int insn_cond;
 292 };
 293
 294 #ifdef OBJ_ELF
 295 # define obj_frob_symbol(sym, punt)     armelf_frob_symbol ((sym), & (punt))
 296 # define md_elf_section_change_hook()   arm_elf_change_section ()
 297 # define md_elf_section_type(str, len)  arm_elf_section_type (str, len)
 298 # define GLOBAL_OFFSET_TABLE_NAME       "_GLOBAL_OFFSET_TABLE_"
 299 # define TC_SEGMENT_INFO_TYPE           struct arm_segment_info_type
 300
 301 /* This is not really an alignment operation, but it's something we
 302    need to do at the same time: whenever we are figuring out the
 303    alignment for data, we should check whether a $d symbol is
 304    necessary.  */
 305 # define md_cons_align(nbytes)          mapping_state (MAP_DATA)
 306
 307 enum mstate
 308 {
 309   MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections.  */
 310   MAP_DATA,
 311   MAP_ARM,
 312   MAP_THUMB
 313 };
 314
 315 void mapping_state (enum mstate);
 316
 317 struct arm_segment_info_type
 318 {
 319   enum mstate mapstate;
 320
 321   /* Bit N indicates that an R_ARM_NONE relocation has been output for
 322      __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
 323      emitted only once per section, to save unnecessary bloat.  */
 324   unsigned int marked_pr_dependency;
 325
 326   struct current_it current_it;
 327 };
 328
 329 /* We want .cfi_* pseudo-ops for generating unwind info.  */
 330 #define TARGET_USE_CFIPOP              1
 331
 332 /* CFI hooks.  */
 333 #define tc_regname_to_dw2regnum            tc_arm_regname_to_dw2regnum
 334 #define tc_cfi_frame_initial_instructions  tc_arm_frame_initial_instructions
 335
 336 #else /* Not OBJ_ELF.  */
 337 #define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
 338 #endif
 339
 340 #if defined OBJ_ELF || defined OBJ_COFF
 341
 342 # define EXTERN_FORCE_RELOC                     1
 343 # define tc_fix_adjustable(FIX)                 arm_fix_adjustable (FIX)
 344 #endif
 345
 346 #ifdef OBJ_ELF
 347 /* Values passed to md_apply_fix don't include the symbol value.  */
 348 # define MD_APPLY_SYM_VALUE(FIX)                arm_apply_sym_value (FIX, this_segment)
 349 #endif
 350
 351 #ifdef OBJ_COFF
 352 # define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL)   arm_validate_fix (FIX)
 353 /* Values passed to md_apply_fix don't include the symbol value.  */
 354 # define MD_APPLY_SYM_VALUE(FIX)                0
 355 #endif
 356
 357 #define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)
 358
 359 extern long md_pcrel_from_section (struct fix *, segT);
 360 extern void arm_frag_align_code (int, int);
 361 extern void arm_validate_fix (struct fix *);
 362 extern const char * elf32_arm_target_format (void);
 363 extern void arm_elf_change_section (void);
 364 extern int arm_force_relocation (struct fix *);
 365 extern void arm_cleanup (void);
 366 extern void arm_start_line_hook (void);
 367 extern void arm_frob_label (symbolS *);
 368 extern int arm_data_in_code (void);
 369 extern char * arm_canonicalize_symbol_name (char *);
 370 extern void arm_adjust_symtab (void);
 371 extern void armelf_frob_symbol (symbolS *, int *);
 372 extern void cons_fix_new_arm (fragS *, int, int, expressionS *,
 373                               bfd_reloc_code_real_type);
 374 extern void arm_init_frag (struct frag *, int);
 375 extern void arm_handle_align (struct frag *);
 376 extern bfd_boolean arm_fix_adjustable (struct fix *);
 377 extern int arm_elf_section_type (const char *, size_t);
 378 extern int tc_arm_regname_to_dw2regnum (char *regname);
 379 extern void tc_arm_frame_initial_instructions (void);
 380
 381 #ifdef TE_PE
 382
 383 #define O_secrel O_md1
 384
 385 #define TC_DWARF2_EMIT_OFFSET  tc_pe_dwarf2_emit_offset
 386 void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);
 387
 388 #endif /* TE_PE */
 389
 390 #ifdef OBJ_ELF
 391 #define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
 392 extern int arm_convert_symbolic_attribute (const char *);
 393 extern int arm_apply_sym_value (struct fix *, segT);
 394 #endif
 395
 396 #define tc_comment_chars arm_comment_chars
 397 extern char arm_comment_chars[];
 398
 399 #define tc_line_separator_chars arm_line_separator_chars
 400 extern char arm_line_separator_chars[];
 401
 402 #define TC_EQUAL_IN_INSN(c, s) arm_tc_equal_in_insn ((c), (s))
 403 extern bfd_boolean arm_tc_equal_in_insn (int, char *);