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