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 #define tc_symbol_chars arm_symbol_chars
  85 extern const char arm_symbol_chars[];
  86
  87 #define TC_FORCE_RELOCATION(FIX) arm_force_relocation (FIX)
  88
  89 extern unsigned int arm_frag_max_var (struct frag *);
  90 #define md_frag_max_var arm_frag_max_var
  91
  92 #define md_relax_frag(segment, fragp, stretch) \
  93   arm_relax_frag (segment, fragp, stretch)
  94 extern int arm_relax_frag (asection *, struct frag *, long);
  95
  96 #define md_optimize_expr(l,o,r)         arm_optimize_expr (l, o, r)
  97 extern int arm_optimize_expr (expressionS *, operatorT, expressionS *);
  98
  99 #define md_cleanup() arm_cleanup ()
 100
 101 #define md_start_line_hook() arm_start_line_hook ()
 102
 103 #define tc_frob_label(S) arm_frob_label (S)
 104
 105 /* We also need to mark assembler created symbols:  */
 106 #define tc_frob_fake_label(S) arm_frob_label (S)
 107
 108 #ifdef OBJ_ELF
 109 #define md_end arm_md_end
 110 extern void arm_md_end (void);
 111 bfd_boolean arm_is_eabi (void);
 112 #endif
 113
 114 /* NOTE: The fake label creation in stabs.c:s_stab_generic() has
 115    deliberately not been updated to mark assembler created stabs
 116    symbols as Thumb.  */
 117
 118 #define TC_FIX_TYPE int
 119 #define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)
 120
 121 /* We need to keep some local information on symbols.  */
 122
 123 #define TC_SYMFIELD_TYPE        unsigned int
 124 #define ARM_GET_FLAG(s)         (*symbol_get_tc (s))
 125 #define ARM_SET_FLAG(s,v)       (*symbol_get_tc (s) |= (v))
 126 #define ARM_RESET_FLAG(s,v)     (*symbol_get_tc (s) &= ~(v))
 127
 128 #define ARM_FLAG_THUMB          (1 << 0)        /* The symbol is a Thumb symbol rather than an Arm symbol.  */
 129 #define ARM_FLAG_INTERWORK      (1 << 1)        /* The symbol is attached to code that supports interworking.  */
 130 #define THUMB_FLAG_FUNC         (1 << 2)        /* The symbol is attached to the start of a Thumb function.  */
 131
 132 #define ARM_IS_THUMB(s)         (ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
 133 #define ARM_IS_INTERWORK(s)     (ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)
 134
 135 #ifdef OBJ_ELF
 136
 137 /* For ELF objects THUMB_IS_FUNC is inferred from
 138    ARM_IS_THUMB and the function type.  */
 139 #define THUMB_IS_FUNC(s)                                        \
 140   ((s) != NULL                                                  \
 141    && ((arm_is_eabi ()                                          \
 142         && (ARM_IS_THUMB (s))                                   \
 143         && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))       \
 144        || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))
 145
 146 #define ARM_IS_FUNC(s)                                  \
 147   (((s) != NULL                                         \
 148     && arm_is_eabi ()                                   \
 149     && !(ARM_IS_THUMB (s))                              \
 150     /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */    \
 151     && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))
 152
 153
 154 #else
 155
 156 #define THUMB_IS_FUNC(s)        ((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
 157 #define ARM_IS_FUNC(s)          (!THUMB_IS_FUNC (s) \
 158                                  && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
 159 #endif
 160
 161 #define ARM_SET_THUMB(s,t)      ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB)     : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
 162 #define ARM_SET_INTERWORK(s,t)  ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
 163 #define THUMB_SET_FUNC(s,t)     ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC)    : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))
 164
 165 void arm_copy_symbol_attributes (symbolS *, symbolS *);
 166
 167 #ifndef TC_COPY_SYMBOL_ATTRIBUTES
 168 #define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
 169   (arm_copy_symbol_attributes (DEST, SRC))
 170 #endif
 171
 172 #define TC_START_LABEL(C,S,STR)            (C == ':' || (C == '/' && arm_data_in_code ()))
 173 #define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
 174 #define obj_adjust_symtab()              arm_adjust_symtab ()
 175
 176 #define LISTING_HEADER "ARM GAS "
 177
 178 #define OPTIONAL_REGISTER_PREFIX '%'
 179
 180 #define LOCAL_LABEL(name)  (name[0] == '.' && name[1] == 'L')
 181 #define LOCAL_LABELS_FB    1
 182
 183 /* This expression evaluates to true if the relocation is for a local
 184    object for which we still want to do the relocation at runtime.
 185    False if we are willing to perform this relocation while building
 186    the .o file.  GOTOFF does not need to be checked here because it is
 187    not pcrel.  I am not sure if some of the others are ever used with
 188    pcrel, but it is easier to be safe than sorry.  */
 189
 190 #define TC_FORCE_RELOCATION_LOCAL(FIX)                  \
 191   (!(FIX)->fx_pcrel                                     \
 192    || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32           \
 193    || (FIX)->fx_r_type == BFD_RELOC_32                  \
 194    || ((FIX)->fx_addsy != NULL && S_IS_WEAK ((FIX)->fx_addsy))  \
 195    || TC_FORCE_RELOCATION (FIX))
 196
 197 /* Force output of R_ARM_REL32 relocations against thumb function symbols.
 198    This is needed to ensure the low bit is handled correctly.  */
 199 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG)  \
 200   (THUMB_IS_FUNC ((FIX)->fx_addsy)              \
 201    || !SEG_NORMAL (SEG))
 202
 203 #define TC_FORCE_RELOCATION_ABS(FIX)                    \
 204   (((FIX)->fx_pcrel                                     \
 205     && (FIX)->fx_r_type != BFD_RELOC_32                 \
 206     && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32)         \
 207    || TC_FORCE_RELOCATION(FIX))
 208
 209 #define TC_CONS_FIX_NEW cons_fix_new_arm
 210
 211 #define MAX_MEM_ALIGNMENT_BYTES    6
 212 #define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)
 213
 214 /* For frags in code sections we need to record whether they contain
 215    ARM code or THUMB code.  This is that if they have to be aligned,
 216    they can contain the correct type of no-op instruction.  */
 217 struct arm_frag_type
 218 {
 219   int thumb_mode;
 220 #ifdef OBJ_ELF
 221   /* If there is a mapping symbol at offset 0 in this frag,
 222      it will be saved in FIRST_MAP.  If there are any mapping
 223      symbols in this frag, the last one will be saved in
 224      LAST_MAP.  */
 225   symbolS *first_map, *last_map;
 226 #endif
 227 };
 228
 229 #define TC_FRAG_TYPE            struct arm_frag_type
 230 /* NOTE: max_chars is a local variable from frag_var / frag_variant.  */
 231 #define TC_FRAG_INIT(fragp)     arm_init_frag (fragp, max_chars)
 232 #define HANDLE_ALIGN(fragp)     arm_handle_align (fragp)
 233
 234 #define md_do_align(N, FILL, LEN, MAX, LABEL)                                   \
 235   if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg))     \
 236     {                                                                           \
 237       arm_frag_align_code (N, MAX);                                             \
 238       goto LABEL;                                                               \
 239     }
 240
 241 #define DWARF2_LINE_MIN_INSN_LENGTH     2
 242
 243 /* The lr register is r14.  */
 244 #define DWARF2_DEFAULT_RETURN_COLUMN  14
 245
 246 /* Registers are generally saved at negative offsets to the CFA.  */
 247 #define DWARF2_CIE_DATA_ALIGNMENT     (-4)
 248
 249 /* State variables for IT block handling.  */
 250 enum it_state
 251 {
 252   OUTSIDE_IT_BLOCK, MANUAL_IT_BLOCK, AUTOMATIC_IT_BLOCK
 253 };
 254 struct current_it
 255 {
 256   int mask;
 257   enum it_state state;
 258   int cc;
 259   int block_length;
 260   char *insn;
 261   int state_handled;
 262   int warn_deprecated;
 263   int insn_cond;
 264 };
 265
 266 #ifdef OBJ_ELF
 267 # define obj_frob_symbol(sym, punt)     armelf_frob_symbol ((sym), & (punt))
 268 # define md_elf_section_change_hook()   arm_elf_change_section ()
 269 # define md_elf_section_type(str, len)  arm_elf_section_type (str, len)
 270 # define GLOBAL_OFFSET_TABLE_NAME       "_GLOBAL_OFFSET_TABLE_"
 271 # define TC_SEGMENT_INFO_TYPE           struct arm_segment_info_type
 272
 273 /* This is not really an alignment operation, but it's something we
 274    need to do at the same time: whenever we are figuring out the
 275    alignment for data, we should check whether a $d symbol is
 276    necessary.  */
 277 # define md_cons_align(nbytes)          mapping_state (MAP_DATA)
 278
 279 enum mstate
 280 {
 281   MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections.  */
 282   MAP_DATA,
 283   MAP_ARM,
 284   MAP_THUMB
 285 };
 286
 287 void mapping_state (enum mstate);
 288
 289 struct arm_segment_info_type
 290 {
 291   enum mstate mapstate;
 292
 293   /* Bit N indicates that an R_ARM_NONE relocation has been output for
 294      __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
 295      emitted only once per section, to save unnecessary bloat.  */
 296   unsigned int marked_pr_dependency;
 297
 298   struct current_it current_it;
 299 };
 300
 301 /* We want .cfi_* pseudo-ops for generating unwind info.  */
 302 #define TARGET_USE_CFIPOP              1
 303
 304 /* CFI hooks.  */
 305 #define tc_regname_to_dw2regnum            tc_arm_regname_to_dw2regnum
 306 #define tc_cfi_frame_initial_instructions  tc_arm_frame_initial_instructions
 307
 308 #else /* Not OBJ_ELF.  */
 309 #define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
 310 #endif
 311
 312 #if defined OBJ_ELF || defined OBJ_COFF
 313
 314 # define EXTERN_FORCE_RELOC                     1
 315 # define tc_fix_adjustable(FIX)                 arm_fix_adjustable (FIX)
 316 #endif
 317
 318 #ifdef OBJ_ELF
 319 /* Values passed to md_apply_fix don't include the symbol value.  */
 320 # define MD_APPLY_SYM_VALUE(FIX)                arm_apply_sym_value (FIX)
 321 #endif
 322
 323 #ifdef OBJ_COFF
 324 # define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL)   arm_validate_fix (FIX)
 325 /* Values passed to md_apply_fix don't include the symbol value.  */
 326 # define MD_APPLY_SYM_VALUE(FIX)                0
 327 #endif
 328
 329 #define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)
 330
 331 extern long md_pcrel_from_section (struct fix *, segT);
 332 extern void arm_frag_align_code (int, int);
 333 extern void arm_validate_fix (struct fix *);
 334 extern const char * elf32_arm_target_format (void);
 335 extern void arm_elf_change_section (void);
 336 extern int arm_force_relocation (struct fix *);
 337 extern void arm_cleanup (void);
 338 extern void arm_start_line_hook (void);
 339 extern void arm_frob_label (symbolS *);
 340 extern int arm_data_in_code (void);
 341 extern char * arm_canonicalize_symbol_name (char *);
 342 extern void arm_adjust_symtab (void);
 343 extern void armelf_frob_symbol (symbolS *, int *);
 344 extern void cons_fix_new_arm (fragS *, int, int, expressionS *);
 345 extern void arm_init_frag (struct frag *, int);
 346 extern void arm_handle_align (struct frag *);
 347 extern bfd_boolean arm_fix_adjustable (struct fix *);
 348 extern int arm_elf_section_type (const char *, size_t);
 349 extern int tc_arm_regname_to_dw2regnum (char *regname);
 350 extern void tc_arm_frame_initial_instructions (void);
 351
 352 #ifdef TE_PE
 353
 354 #define O_secrel O_md1
 355
 356 #define TC_DWARF2_EMIT_OFFSET  tc_pe_dwarf2_emit_offset
 357 void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);
 358
 359 #endif /* TE_PE */
 360
 361 #ifdef OBJ_ELF
 362 #define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
 363 extern int arm_convert_symbolic_attribute (const char *);
 364 extern int arm_apply_sym_value (struct fix *);
 365 #endif