gas/config/tc-arm.h

   1 /* This file is tc-arm.h
   2    Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
   3    2004, 2005, 2006, 2007, 2008, 2009, 2012  Free Software Foundation, Inc.
   4    Contributed by Richard Earnshaw (rwe@pegasus.esprit.ec.org)
   5         Modified by David Taylor (dtaylor@armltd.co.uk)
   6
   7    This file is part of GAS, the GNU Assembler.
   8
   9    GAS is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3, or (at your option)
  12    any later version.
  13
  14    GAS is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with GAS; see the file COPYING.  If not, write to the Free
  21    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  22    02110-1301, USA.  */
  23
  24 #define TC_ARM 1
  25
  26 #ifndef TARGET_BYTES_BIG_ENDIAN
  27 #define TARGET_BYTES_BIG_ENDIAN 0
  28 #endif
  29
  30 #define WORKING_DOT_WORD
  31
  32 #define COFF_MAGIC      ARMMAGIC
  33 #define TARGET_ARCH     bfd_arch_arm
  34
  35 #define DIFF_EXPR_OK
  36
  37 #ifdef  LITTLE_ENDIAN
  38 #undef  LITTLE_ENDIAN
  39 #endif
  40
  41 #ifdef  BIG_ENDIAN
  42 #undef  BIG_ENDIAN
  43 #endif
  44
  45 #define LITTLE_ENDIAN   1234
  46 #define BIG_ENDIAN      4321
  47
  48 struct fix;
  49
  50 #if defined OBJ_AOUT
  51 # if defined TE_RISCIX
  52 #  define TARGET_FORMAT "a.out-riscix"
  53 # elif defined TE_LINUX
  54 #  define ARM_BI_ENDIAN
  55 #  define TARGET_FORMAT "a.out-arm-linux"
  56 # elif defined TE_NetBSD
  57 #  define TARGET_FORMAT "a.out-arm-netbsd"
  58 # else
  59 #  define ARM_BI_ENDIAN
  60 #  define TARGET_FORMAT (target_big_endian ? "a.out-arm-big" : "a.out-arm-little")
  61 # endif
  62 #elif defined OBJ_AIF
  63 # define TARGET_FORMAT "aif"
  64 #elif defined OBJ_COFF
  65 # define ARM_BI_ENDIAN
  66 # if defined TE_PE
  67 #  if defined TE_EPOC
  68 #   define TARGET_FORMAT (target_big_endian ? "epoc-pe-arm-big" : "epoc-pe-arm-little")
  69 #  elif defined TE_WINCE
  70 #   define TARGET_FORMAT (target_big_endian ? "pe-arm-wince-big" : "pe-arm-wince-little")
  71 #  else
  72 #   define TARGET_FORMAT (target_big_endian ? "pe-arm-big" : "pe-arm-little")
  73 #  endif
  74 # else
  75 #  define TARGET_FORMAT (target_big_endian ? "coff-arm-big" : "coff-arm-little")
  76 # endif
  77 #elif defined OBJ_ELF
  78 # define ARM_BI_ENDIAN
  79 # define TARGET_FORMAT  elf32_arm_target_format ()
  80 #endif
  81
  82 /* We support double slash line-comments for compatibility with the ARM AArch64 Assembler.  */
  83 #define DOUBLESLASH_LINE_COMMENTS
  84
  85 #define TC_FORCE_RELOCATION(FIX) arm_force_relocation (FIX)
  86
  87 extern unsigned int arm_frag_max_var (struct frag *);
  88 #define md_frag_max_var arm_frag_max_var
  89
  90 #define md_relax_frag(segment, fragp, stretch) \
  91   arm_relax_frag (segment, fragp, stretch)
  92 extern int arm_relax_frag (asection *, struct frag *, long);
  93
  94 #define md_optimize_expr(l,o,r)         arm_optimize_expr (l, o, r)
  95 extern int arm_optimize_expr (expressionS *, operatorT, expressionS *);
  96
  97 #define md_cleanup() arm_cleanup ()
  98
  99 #define md_start_line_hook() arm_start_line_hook ()
 100
 101 #define tc_frob_label(S) arm_frob_label (S)
 102
 103 /* We also need to mark assembler created symbols:  */
 104 #define tc_frob_fake_label(S) arm_frob_label (S)
 105
 106 #ifdef OBJ_ELF
 107 #define md_end arm_md_end
 108 extern void arm_md_end (void);
 109 bfd_boolean arm_is_eabi (void);
 110 #endif
 111
 112 /* NOTE: The fake label creation in stabs.c:s_stab_generic() has
 113    deliberately not been updated to mark assembler created stabs
 114    symbols as Thumb.  */
 115
 116 #define TC_FIX_TYPE int
 117 #define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)
 118
 119 /* We need to keep some local information on symbols.  */
 120
 121 #define TC_SYMFIELD_TYPE        unsigned int
 122 #define ARM_GET_FLAG(s)         (*symbol_get_tc (s))
 123 #define ARM_SET_FLAG(s,v)       (*symbol_get_tc (s) |= (v))
 124 #define ARM_RESET_FLAG(s,v)     (*symbol_get_tc (s) &= ~(v))
 125
 126 #define ARM_FLAG_THUMB          (1 << 0)        /* The symbol is a Thumb symbol rather than an Arm symbol.  */
 127 #define ARM_FLAG_INTERWORK      (1 << 1)        /* The symbol is attached to code that supports interworking.  */
 128 #define THUMB_FLAG_FUNC         (1 << 2)        /* The symbol is attached to the start of a Thumb function.  */
 129
 130 #define ARM_IS_THUMB(s)         (ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
 131 #define ARM_IS_INTERWORK(s)     (ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)
 132
 133 #ifdef OBJ_ELF
 134
 135 /* For ELF objects THUMB_IS_FUNC is inferred from
 136    ARM_IS_THUMB and the function type.  */
 137 #define THUMB_IS_FUNC(s)                                        \
 138   ((s) != NULL                                                  \
 139    && ((arm_is_eabi ()                                          \
 140         && (ARM_IS_THUMB (s))                                   \
 141         && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))       \
 142        || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))
 143
 144 #define ARM_IS_FUNC(s)                                  \
 145   (((s) != NULL                                         \
 146     && arm_is_eabi ()                                   \
 147     && !(ARM_IS_THUMB (s))                              \
 148     /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */    \
 149     && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))
 150
 151
 152 #else
 153
 154 #define THUMB_IS_FUNC(s)        ((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
 155 #define ARM_IS_FUNC(s)          (!THUMB_IS_FUNC (s) \
 156                                  && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
 157 #endif
 158
 159 #define ARM_SET_THUMB(s,t)      ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB)     : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
 160 #define ARM_SET_INTERWORK(s,t)  ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
 161 #define THUMB_SET_FUNC(s,t)     ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC)    : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))
 162
 163 void arm_copy_symbol_attributes (symbolS *, symbolS *);
 164
 165 #ifndef TC_COPY_SYMBOL_ATTRIBUTES
 166 #define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
 167   (arm_copy_symbol_attributes (DEST, SRC))
 168 #endif
 169
 170 #define TC_START_LABEL(C,S,STR)            (C == ':' || (C == '/' && arm_data_in_code ()))
 171 #define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
 172 #define obj_adjust_symtab()              arm_adjust_symtab ()
 173
 174 #define LISTING_HEADER "ARM GAS "
 175
 176 #define OPTIONAL_REGISTER_PREFIX '%'
 177
 178 #define LOCAL_LABEL(name)  (name[0] == '.' && name[1] == 'L')
 179 #define LOCAL_LABELS_FB    1
 180
 181 /* This expression evaluates to true if the relocation is for a local
 182    object for which we still want to do the relocation at runtime.
 183    False if we are willing to perform this relocation while building
 184    the .o file.  GOTOFF does not need to be checked here because it is
 185    not pcrel.  I am not sure if some of the others are ever used with
 186    pcrel, but it is easier to be safe than sorry.  */
 187
 188 #define TC_FORCE_RELOCATION_LOCAL(FIX)                  \
 189   (!(FIX)->fx_pcrel                                     \
 190    || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32           \
 191    || (FIX)->fx_r_type == BFD_RELOC_32                  \
 192    || ((FIX)->fx_addsy != NULL && S_IS_WEAK ((FIX)->fx_addsy))  \
 193    || TC_FORCE_RELOCATION (FIX))
 194
 195 /* Force output of R_ARM_REL32 relocations against thumb function symbols.
 196    This is needed to ensure the low bit is handled correctly.  */
 197 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG)  \
 198   (THUMB_IS_FUNC ((FIX)->fx_addsy)              \
 199    || !SEG_NORMAL (SEG))
 200
 201 #define TC_FORCE_RELOCATION_ABS(FIX)                    \
 202   (((FIX)->fx_pcrel                                     \
 203     && (FIX)->fx_r_type != BFD_RELOC_32                 \
 204     && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32)         \
 205    || TC_FORCE_RELOCATION(FIX))
 206
 207 #define TC_CONS_FIX_NEW cons_fix_new_arm
 208
 209 #define MAX_MEM_ALIGNMENT_BYTES    6
 210 #define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)
 211
 212 /* For frags in code sections we need to record whether they contain
 213    ARM code or THUMB code.  This is that if they have to be aligned,
 214    they can contain the correct type of no-op instruction.  */
 215 struct arm_frag_type
 216 {
 217   int thumb_mode;
 218 #ifdef OBJ_ELF
 219   /* If there is a mapping symbol at offset 0 in this frag,
 220      it will be saved in FIRST_MAP.  If there are any mapping
 221      symbols in this frag, the last one will be saved in
 222      LAST_MAP.  */
 223   symbolS *first_map, *last_map;
 224 #endif
 225 };
 226
 227 #define TC_FRAG_TYPE            struct arm_frag_type
 228 /* NOTE: max_chars is a local variable from frag_var / frag_variant.  */
 229 #define TC_FRAG_INIT(fragp)     arm_init_frag (fragp, max_chars)
 230 #define HANDLE_ALIGN(fragp)     arm_handle_align (fragp)
 231
 232 #define md_do_align(N, FILL, LEN, MAX, LABEL)                                   \
 233   if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg))     \
 234     {                                                                           \
 235       arm_frag_align_code (N, MAX);                                             \
 236       goto LABEL;                                                               \
 237     }
 238
 239 #define DWARF2_LINE_MIN_INSN_LENGTH     2
 240
 241 /* The lr register is r14.  */
 242 #define DWARF2_DEFAULT_RETURN_COLUMN  14
 243
 244 /* Registers are generally saved at negative offsets to the CFA.  */
 245 #define DWARF2_CIE_DATA_ALIGNMENT     (-4)
 246
 247 /* State variables for IT block handling.  */
 248 enum it_state
 249 {
 250   OUTSIDE_IT_BLOCK, MANUAL_IT_BLOCK, AUTOMATIC_IT_BLOCK
 251 };
 252 struct current_it
 253 {
 254   int mask;
 255   enum it_state state;
 256   int cc;
 257   int block_length;
 258   char *insn;
 259   int state_handled;
 260 };
 261
 262 #ifdef OBJ_ELF
 263 # define obj_frob_symbol(sym, punt)     armelf_frob_symbol ((sym), & (punt))
 264 # define md_elf_section_change_hook()   arm_elf_change_section ()
 265 # define md_elf_section_type(str, len)  arm_elf_section_type (str, len)
 266 # define GLOBAL_OFFSET_TABLE_NAME       "_GLOBAL_OFFSET_TABLE_"
 267 # define TC_SEGMENT_INFO_TYPE           struct arm_segment_info_type
 268
 269 /* This is not really an alignment operation, but it's something we
 270    need to do at the same time: whenever we are figuring out the
 271    alignment for data, we should check whether a $d symbol is
 272    necessary.  */
 273 # define md_cons_align(nbytes)          mapping_state (MAP_DATA)
 274
 275 enum mstate
 276 {
 277   MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections.  */
 278   MAP_DATA,
 279   MAP_ARM,
 280   MAP_THUMB
 281 };
 282
 283 void mapping_state (enum mstate);
 284
 285 struct arm_segment_info_type
 286 {
 287   enum mstate mapstate;
 288
 289   /* Bit N indicates that an R_ARM_NONE relocation has been output for
 290      __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
 291      emitted only once per section, to save unnecessary bloat.  */
 292   unsigned int marked_pr_dependency;
 293
 294   struct current_it current_it;
 295 };
 296
 297 /* We want .cfi_* pseudo-ops for generating unwind info.  */
 298 #define TARGET_USE_CFIPOP              1
 299
 300 /* CFI hooks.  */
 301 #define tc_regname_to_dw2regnum            tc_arm_regname_to_dw2regnum
 302 #define tc_cfi_frame_initial_instructions  tc_arm_frame_initial_instructions
 303
 304 #else /* Not OBJ_ELF.  */
 305 #define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
 306 #endif
 307
 308 #if defined OBJ_ELF || defined OBJ_COFF
 309
 310 # define EXTERN_FORCE_RELOC                     1
 311 # define tc_fix_adjustable(FIX)                 arm_fix_adjustable (FIX)
 312 #endif
 313
 314 #ifdef OBJ_ELF
 315 /* Values passed to md_apply_fix don't include the symbol value.  */
 316 # define MD_APPLY_SYM_VALUE(FIX)                arm_apply_sym_value (FIX)
 317 #endif
 318
 319 #ifdef OBJ_COFF
 320 # define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL)   arm_validate_fix (FIX)
 321 /* Values passed to md_apply_fix don't include the symbol value.  */
 322 # define MD_APPLY_SYM_VALUE(FIX)                0
 323 #endif
 324
 325 #define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)
 326
 327 extern long md_pcrel_from_section (struct fix *, segT);
 328 extern void arm_frag_align_code (int, int);
 329 extern void arm_validate_fix (struct fix *);
 330 extern const char * elf32_arm_target_format (void);
 331 extern void arm_elf_change_section (void);
 332 extern int arm_force_relocation (struct fix *);
 333 extern void arm_cleanup (void);
 334 extern void arm_start_line_hook (void);
 335 extern void arm_frob_label (symbolS *);
 336 extern int arm_data_in_code (void);
 337 extern char * arm_canonicalize_symbol_name (char *);
 338 extern void arm_adjust_symtab (void);
 339 extern void armelf_frob_symbol (symbolS *, int *);
 340 extern void cons_fix_new_arm (fragS *, int, int, expressionS *);
 341 extern void arm_init_frag (struct frag *, int);
 342 extern void arm_handle_align (struct frag *);
 343 extern bfd_boolean arm_fix_adjustable (struct fix *);
 344 extern int arm_elf_section_type (const char *, size_t);
 345 extern int tc_arm_regname_to_dw2regnum (char *regname);
 346 extern void tc_arm_frame_initial_instructions (void);
 347
 348 #ifdef TE_PE
 349
 350 #define O_secrel O_md1
 351
 352 #define TC_DWARF2_EMIT_OFFSET  tc_pe_dwarf2_emit_offset
 353 void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);
 354
 355 #endif /* TE_PE */
 356
 357 #ifdef OBJ_ELF
 358 #define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
 359 extern int arm_convert_symbolic_attribute (const char *);
 360 extern int arm_apply_sym_value (struct fix *);
 361 #endif