gas/config/tc-arm.h

/* This file is tc-arm.h
   Copyright (C) 1994-2021 Free Software Foundation, Inc.
   Contributed by Richard Earnshaw (rwe@pegasus.esprit.ec.org)
	Modified by David Taylor (dtaylor@armltd.co.uk)

   This file is part of GAS, the GNU Assembler.

   GAS is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   GAS is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GAS; see the file COPYING.  If not, write to the Free
   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
   02110-1301, USA.  */

#define TC_ARM 1

#ifndef TARGET_BYTES_BIG_ENDIAN
#define TARGET_BYTES_BIG_ENDIAN 0
#endif

#define WORKING_DOT_WORD

#define COFF_MAGIC 	ARMMAGIC
#define TARGET_ARCH 	bfd_arch_arm

#define DIFF_EXPR_OK

#ifdef  LITTLE_ENDIAN
#undef  LITTLE_ENDIAN
#endif

#ifdef  BIG_ENDIAN
#undef  BIG_ENDIAN
#endif

#define LITTLE_ENDIAN 	1234
#define BIG_ENDIAN 	4321

struct fix;

#if defined OBJ_COFF
# define ARM_BI_ENDIAN
# if defined TE_PE
#  if defined TE_WINCE
#   define TARGET_FORMAT (target_big_endian ? "pe-arm-wince-big" : "pe-arm-wince-little")
#  else
#   define TARGET_FORMAT (target_big_endian ? "pe-arm-big" : "pe-arm-little")
#  endif
# else
#  define TARGET_FORMAT (target_big_endian ? "coff-arm-big" : "coff-arm-little")
# endif
#elif defined OBJ_ELF
# define ARM_BI_ENDIAN
# define TARGET_FORMAT	elf32_arm_target_format ()
#endif

/* We support double slash line-comments for compatibility with the ARM AArch64 Assembler.  */
#define DOUBLESLASH_LINE_COMMENTS

/* We conditionally support labels without a colon.  */
#define LABELS_WITHOUT_COLONS codecomposer_syntax
extern bool codecomposer_syntax;

#define tc_symbol_chars arm_symbol_chars
extern const char arm_symbol_chars[];

#define TC_FORCE_RELOCATION(FIX) arm_force_relocation (FIX)

extern unsigned int arm_frag_max_var (struct frag *);
#define md_frag_max_var arm_frag_max_var

#define md_relax_frag(segment, fragp, stretch) \
  arm_relax_frag (segment, fragp, stretch)
extern int arm_relax_frag (asection *, struct frag *, long);

#define md_optimize_expr(l,o,r)		arm_optimize_expr (l, o, r)
extern bool arm_optimize_expr (expressionS *, operatorT, expressionS *);

#define md_cleanup() arm_cleanup ()

#define md_start_line_hook() arm_start_line_hook ()

#define TC_START_LABEL_WITHOUT_COLON(NUL_CHAR, NEXT_CHAR) \
  tc_start_label_without_colon ()
extern bool tc_start_label_without_colon (void);

#define tc_frob_label(S) arm_frob_label (S)

/* We also need to mark assembler created symbols:  */
#define tc_frob_fake_label(S) arm_frob_label (S)

#ifdef OBJ_ELF
#define md_end arm_md_end
extern void arm_md_end (void);
bool arm_is_eabi (void);

#define md_post_relax_hook		arm_md_post_relax ()
extern void arm_md_post_relax (void);
#endif

/* NOTE: The fake label creation in stabs.c:s_stab_generic() has
   deliberately not been updated to mark assembler created stabs
   symbols as Thumb.  */

#define TC_FIX_TYPE int
#define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)

/* We need to keep some local information on symbols.  */

#define TC_SYMFIELD_TYPE 	unsigned int
#define ARM_GET_FLAG(s)   	(*symbol_get_tc (s))
#define ARM_SET_FLAG(s,v) 	(*symbol_get_tc (s) |= (v))
#define ARM_RESET_FLAG(s,v) 	(*symbol_get_tc (s) &= ~(v))

#define ARM_FLAG_THUMB 		(1 << 0)	/* The symbol is a Thumb symbol rather than an Arm symbol.  */
#define ARM_FLAG_INTERWORK 	(1 << 1)	/* The symbol is attached to code that supports interworking.  */
#define THUMB_FLAG_FUNC		(1 << 2)	/* The symbol is attached to the start of a Thumb function.  */

#define ARM_IS_THUMB(s)		(ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
#define ARM_IS_INTERWORK(s)	(ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)

#ifdef OBJ_ELF

/* For ELF objects THUMB_IS_FUNC is inferred from
   ARM_IS_THUMB and the function type.  */
#define THUMB_IS_FUNC(s)					\
  ((s) != NULL							\
   && ((arm_is_eabi ()						\
	&& (ARM_IS_THUMB (s))					\
	&& (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))	\
       || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))

#define ARM_IS_FUNC(s)					\
  (((s) != NULL						\
    && arm_is_eabi ()					\
    && !(ARM_IS_THUMB (s))				\
    /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */	\
    && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))


#else

#define THUMB_IS_FUNC(s)	((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
#define ARM_IS_FUNC(s)          (!THUMB_IS_FUNC (s) \
				 && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
#endif

#define ARM_SET_THUMB(s,t)      ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB)     : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
#define ARM_SET_INTERWORK(s,t)  ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
#define THUMB_SET_FUNC(s,t)     ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC)    : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))

void arm_copy_symbol_attributes (symbolS *, symbolS *);

#ifndef TC_COPY_SYMBOL_ATTRIBUTES
#define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
  (arm_copy_symbol_attributes (DEST, SRC))
#endif

#define TC_START_LABEL(STR, NUL_CHAR, NEXT_CHAR)			\
  (NEXT_CHAR == ':' || (NEXT_CHAR == '/' && arm_data_in_code ()))
#define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
#define obj_adjust_symtab() 		 arm_adjust_symtab ()

#define LISTING_HEADER "ARM GAS "

#define OPTIONAL_REGISTER_PREFIX '%'

#define LOCAL_LABEL(name)  (name[0] == '.' && name[1] == 'L')
#define LOCAL_LABELS_FB    1

/* This expression evaluates to true if the relocation is for a local
   object for which we still want to do the relocation at runtime.
   False if we are willing to perform this relocation while building
   the .o file.  GOTOFF does not need to be checked here because it is
   not pcrel.  I am not sure if some of the others are ever used with
   pcrel, but it is easier to be safe than sorry.  */

#define TC_FORCE_RELOCATION_LOCAL(FIX)			\
  (GENERIC_FORCE_RELOCATION_LOCAL (FIX)			\
   || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32		\
   || (FIX)->fx_r_type == BFD_RELOC_32			\
   || ((FIX)->fx_addsy != NULL				\
       && S_IS_WEAK ((FIX)->fx_addsy)))

/* Force output of R_ARM_REL32 relocations against thumb function symbols.
   This is needed to ensure the low bit is handled correctly.  */
#define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG)	\
  (GENERIC_FORCE_RELOCATION_SUB_SAME (FIX, SEG)	\
   || THUMB_IS_FUNC ((FIX)->fx_addsy))

#define TC_FORCE_RELOCATION_ABS(FIX)			\
  (((FIX)->fx_pcrel					\
    && (FIX)->fx_r_type != BFD_RELOC_32			\
    && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32)		\
   || TC_FORCE_RELOCATION(FIX))

#define TC_CONS_FIX_NEW cons_fix_new_arm

#define MAX_MEM_ALIGNMENT_BYTES    6
#define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)

/* For frags in code sections we need to record whether they contain
   ARM code or THUMB code.  This is that if they have to be aligned,
   they can contain the correct type of no-op instruction.  */
struct arm_frag_type
{
  int thumb_mode;
#ifdef OBJ_ELF
  /* If there is a mapping symbol at offset 0 in this frag,
     it will be saved in FIRST_MAP.  If there are any mapping
     symbols in this frag, the last one will be saved in
     LAST_MAP.  */
  symbolS *first_map, *last_map;
#endif
};

static inline int
arm_min (int am_p1, int am_p2)
{
  return am_p1 < am_p2 ? am_p1 : am_p2;
}

#define TC_FRAG_TYPE		struct arm_frag_type
#define TC_FRAG_INIT(fragp, max_bytes) arm_init_frag (fragp, max_bytes)
#define TC_ALIGN_ZERO_IS_DEFAULT 1
#define HANDLE_ALIGN(fragp)	arm_handle_align (fragp)
/* PR gas/19276: COFF/PE segment alignment is already handled in coff_frob_section().  */
#ifndef TE_PE
#define SUB_SEGMENT_ALIGN(SEG, FRCHAIN)				\
  ((!(FRCHAIN)->frch_next && subseg_text_p (SEG))		\
   ? arm_min (2, get_recorded_alignment (SEG)) : 0)
#endif

#define md_do_align(N, FILL, LEN, MAX, LABEL)					\
  if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg))	\
    {										\
      arm_frag_align_code (N, MAX);						\
      goto LABEL;								\
    }

#define DWARF2_LINE_MIN_INSN_LENGTH 	2

/* The lr register is r14.  */
#define DWARF2_DEFAULT_RETURN_COLUMN  14

/* Registers are generally saved at negative offsets to the CFA.  */
#define DWARF2_CIE_DATA_ALIGNMENT     (-4)

/* State variables for predication block handling.  */
enum pred_state
{
  OUTSIDE_PRED_BLOCK, MANUAL_PRED_BLOCK, AUTOMATIC_PRED_BLOCK
};
enum pred_type {
  SCALAR_PRED, VECTOR_PRED
};
struct current_pred
{
  int mask;
  enum pred_state state;
  int cc;
  int block_length;
  char *insn;
  int state_handled;
  int warn_deprecated;
  int insn_cond;
  enum pred_type type;
};

#ifdef OBJ_ELF
# define obj_frob_symbol(sym, punt)	armelf_frob_symbol ((sym), & (punt))
# define md_elf_section_change_hook()	arm_elf_change_section ()
# define md_elf_section_type(str, len)	arm_elf_section_type (str, len)
# define GLOBAL_OFFSET_TABLE_NAME	"_GLOBAL_OFFSET_TABLE_"
# define TC_SEGMENT_INFO_TYPE 		struct arm_segment_info_type

/* This is not really an alignment operation, but it's something we
   need to do at the same time: whenever we are figuring out the
   alignment for data, we should check whether a $d symbol is
   necessary.  */
# define md_cons_align(nbytes)		mapping_state (MAP_DATA)

enum mstate
{
  MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections.  */
  MAP_DATA,
  MAP_ARM,
  MAP_THUMB
};

void mapping_state (enum mstate);

struct arm_segment_info_type
{
  enum mstate mapstate;

  /* Bit N indicates that an R_ARM_NONE relocation has been output for
     __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
     emitted only once per section, to save unnecessary bloat.  */
  unsigned int marked_pr_dependency;

  struct current_pred current_pred;
};

/* We want .cfi_* pseudo-ops for generating unwind info.  */
#define TARGET_USE_CFIPOP              1

/* CFI hooks.  */
#define tc_regname_to_dw2regnum            tc_arm_regname_to_dw2regnum
#define tc_cfi_frame_initial_instructions  tc_arm_frame_initial_instructions

#else /* Not OBJ_ELF.  */
#define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
#endif

#if defined OBJ_ELF || defined OBJ_COFF

# define EXTERN_FORCE_RELOC 			1
# define tc_fix_adjustable(FIX) 		arm_fix_adjustable (FIX)
#endif

#ifdef OBJ_ELF
/* Values passed to md_apply_fix don't include the symbol value.  */
# define MD_APPLY_SYM_VALUE(FIX) 		arm_apply_sym_value (FIX, this_segment)
#endif

#ifdef OBJ_COFF
# define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL)	arm_validate_fix (FIX)
/* Values passed to md_apply_fix don't include the symbol value.  */
# define MD_APPLY_SYM_VALUE(FIX) 		0
#endif

#define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)

extern void arm_frag_align_code (int, int);
extern void arm_validate_fix (struct fix *);
extern const char * elf32_arm_target_format (void);
extern void arm_elf_change_section (void);
extern int arm_force_relocation (struct fix *);
extern void arm_cleanup (void);
extern void arm_start_line_hook (void);
extern void arm_frob_label (symbolS *);
extern bool arm_data_in_code (void);
extern char * arm_canonicalize_symbol_name (char *);
extern void arm_adjust_symtab (void);
extern void armelf_frob_symbol (symbolS *, int *);
extern void cons_fix_new_arm (fragS *, int, int, expressionS *,
			      bfd_reloc_code_real_type);
extern void arm_init_frag (struct frag *, int);
extern void arm_handle_align (struct frag *);
extern bool arm_fix_adjustable (struct fix *);
extern int arm_elf_section_type (const char *, size_t);
extern int tc_arm_regname_to_dw2regnum (char *regname);
extern void tc_arm_frame_initial_instructions (void);

#ifdef TE_PE

#define O_secrel O_md1

#define TC_DWARF2_EMIT_OFFSET  tc_pe_dwarf2_emit_offset
void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);

#endif /* TE_PE */

#ifdef OBJ_ELF
#define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
extern int arm_convert_symbolic_attribute (const char *);
extern int arm_apply_sym_value (struct fix *, segT);
#endif

#define tc_comment_chars arm_comment_chars
extern char arm_comment_chars[];

#define tc_line_separator_chars arm_line_separator_chars
extern char arm_line_separator_chars[];

#define TC_EQUAL_IN_INSN(c, s) arm_tc_equal_in_insn ((c), (s))
extern bool arm_tc_equal_in_insn (int, char *);

#define TC_LARGEST_EXPONENT_IS_NORMAL(PRECISION) \
	arm_is_largest_exponent_ok ((PRECISION))
int arm_is_largest_exponent_ok (int precision);