gas/config/tc-avr.h

   1 /* This file is tc-avr.h
   2    Copyright (C) 1999-2021 Free Software Foundation, Inc.
   3
   4    Contributed by Denis Chertykov <denisc@overta.ru>
   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 /* By convention, you should define this macro in the `.h' file.  For
  24    example, `tc-m68k.h' defines `TC_M68K'.  You might have to use this
  25    if it is necessary to add CPU specific code to the object format
  26    file.  */
  27 #define TC_AVR
  28
  29 /* This macro is the BFD target name to use when creating the output
  30    file.  This will normally depend upon the `OBJ_FMT' macro.  */
  31 #define TARGET_FORMAT "elf32-avr"
  32
  33 /* This macro is the BFD architecture to pass to `bfd_set_arch_mach'.  */
  34 #define TARGET_ARCH bfd_arch_avr
  35
  36 /* This macro is the BFD machine number to pass to
  37    `bfd_set_arch_mach'.  If it is not defined, GAS will use 0.  */
  38 #define TARGET_MACH 0
  39
  40 /* You should define this macro to be non-zero if the target is big
  41    endian, and zero if the target is little endian.  */
  42 #define TARGET_BYTES_BIG_ENDIAN 0
  43
  44 /* If you define this macro, GAS will warn about the use of
  45    nonstandard escape sequences in a string.  */
  46 #define ONLY_STANDARD_ESCAPES
  47
  48 #define DIFF_EXPR_OK    /* .-foo gets turned into PC relative relocs */
  49
  50 /* GAS will call this function for any expression that can not be
  51    recognized.  When the function is called, `input_line_pointer'
  52    will point to the start of the expression.  */
  53 #define md_operand(x)
  54
  55 typedef struct
  56 {
  57   /* Name of the expression modifier allowed with .byte, .word, etc.  */
  58   const char *name;
  59
  60   /* Only allowed with n bytes of data.  */
  61   int nbytes;
  62
  63   /* Associated RELOC.  */
  64   bfd_reloc_code_real_type reloc;
  65
  66   /* Part of the error message.  */
  67   const char *error;
  68 } exp_mod_data_t;
  69
  70 extern const exp_mod_data_t exp_mod_data[];
  71 #define TC_PARSE_CONS_RETURN_TYPE const exp_mod_data_t *
  72 #define TC_PARSE_CONS_RETURN_NONE exp_mod_data
  73
  74 /* You may define this macro to parse an expression used in a data
  75    allocation pseudo-op such as `.word'.  You can use this to
  76    recognize relocation directives that may appear in such directives.  */
  77 #define TC_PARSE_CONS_EXPRESSION(EXPR,N) avr_parse_cons_expression (EXPR, N)
  78 extern const exp_mod_data_t *avr_parse_cons_expression (expressionS *, int);
  79
  80 /* You may define this macro to generate a fixup for a data
  81    allocation pseudo-op.  */
  82 #define TC_CONS_FIX_NEW avr_cons_fix_new
  83 extern void avr_cons_fix_new (fragS *,int, int, expressionS *,
  84                               const exp_mod_data_t *);
  85
  86 /* This should just call either `number_to_chars_bigendian' or
  87    `number_to_chars_littleendian', whichever is appropriate.  On
  88    targets like the MIPS which support options to change the
  89    endianness, which function to call is a runtime decision.  On
  90    other targets, `md_number_to_chars' can be a simple macro.  */
  91 #define md_number_to_chars number_to_chars_littleendian
  92
  93 /* `md_short_jump_size'
  94    `md_long_jump_size'
  95    `md_create_short_jump'
  96    `md_create_long_jump'
  97    If `WORKING_DOT_WORD' is defined, GAS will not do broken word
  98    processing (*note Broken words::.).  Otherwise, you should set
  99    `md_short_jump_size' to the size of a short jump (a jump that is
 100    just long enough to jump around a long jmp) and
 101    `md_long_jump_size' to the size of a long jump (a jump that can go
 102    anywhere in the function), You should define
 103    `md_create_short_jump' to create a short jump around a long jump,
 104    and define `md_create_long_jump' to create a long jump.  */
 105 #define WORKING_DOT_WORD
 106
 107 /* If you define this macro, it means that `tc_gen_reloc' may return
 108    multiple relocation entries for a single fixup.  In this case, the
 109    return value of `tc_gen_reloc' is a pointer to a null terminated
 110    array.  */
 111 #undef RELOC_EXPANSION_POSSIBLE
 112
 113 /* No shared lib support, so we don't need to ensure externally
 114    visible symbols can be overridden.  */
 115 #define EXTERN_FORCE_RELOC 0
 116
 117 /* If defined, this macro allows control over whether fixups for a
 118    given section will be processed when the linkrelax variable is
 119    set. Define it to zero and handle things in md_apply_fix instead.*/
 120 #define TC_LINKRELAX_FIXUP(SEG) 0
 121
 122 /* If this macro returns non-zero, it guarantees that a relocation will be emitted
 123    even when the value can be resolved locally. Do that if linkrelax is turned on */
 124 #define TC_FORCE_RELOCATION(fix)        avr_force_relocation (fix)
 125 #define TC_FORCE_RELOCATION_SUB_SAME(fix, seg) \
 126   (GENERIC_FORCE_RELOCATION_SUB_SAME (fix, seg) \
 127    || avr_force_relocation (fix))
 128 extern int avr_force_relocation (struct fix *);
 129
 130 /* Values passed to md_apply_fix don't include the symbol value.  */
 131 #define MD_APPLY_SYM_VALUE(FIX) 0
 132
 133 /* If you define this macro, it should return the offset between the
 134    address of a PC relative fixup and the position from which the PC
 135    relative adjustment should be made.  On many processors, the base
 136    of a PC relative instruction is the next instruction, so this
 137    macro would return the length of an instruction.  */
 138 #define MD_PCREL_FROM_SECTION(FIX, SEC) md_pcrel_from_section (FIX, SEC)
 139
 140 /* The number of bytes to put into a word in a listing.  This affects
 141    the way the bytes are clumped together in the listing.  For
 142    example, a value of 2 might print `1234 5678' where a value of 1
 143    would print `12 34 56 78'.  The default value is 4.  */
 144 #define LISTING_WORD_SIZE 2
 145
 146 /* AVR port uses `$' as a logical line separator.  */
 147 #define LEX_DOLLAR 0
 148
 149 /* An `.lcomm' directive with no explicit alignment parameter will
 150    use this macro to set P2VAR to the alignment that a request for
 151    SIZE bytes will have.  The alignment is expressed as a power of
 152    two.  If no alignment should take place, the macro definition
 153    should do nothing.  Some targets define a `.bss' directive that is
 154    also affected by this macro.  The default definition will set
 155    P2VAR to the truncated power of two of sizes up to eight bytes.  */
 156 #define TC_IMPLICIT_LCOMM_ALIGNMENT(SIZE, P2VAR) (P2VAR) = 0
 157
 158 /* We don't want gas to fixup the following program memory related relocations.
 159    We will need them in case that we want to do linker relaxation.
 160    We could in principle keep these fixups in gas when not relaxing.
 161    However, there is no serious performance penalty when making the linker
 162    make the fixup work.  Check also that fx_addsy is not NULL, in order to make
 163    sure that the fixup refers to some sort of label.  */
 164 #define TC_VALIDATE_FIX(FIXP,SEG,SKIP)                       \
 165   if (   (FIXP->fx_r_type == BFD_RELOC_AVR_7_PCREL           \
 166        || FIXP->fx_r_type == BFD_RELOC_AVR_13_PCREL          \
 167        || FIXP->fx_r_type == BFD_RELOC_AVR_LO8_LDI_PM        \
 168        || FIXP->fx_r_type == BFD_RELOC_AVR_LO8_LDI_GS        \
 169        || FIXP->fx_r_type == BFD_RELOC_AVR_HI8_LDI_PM        \
 170        || FIXP->fx_r_type == BFD_RELOC_AVR_HI8_LDI_GS        \
 171        || FIXP->fx_r_type == BFD_RELOC_AVR_HH8_LDI_PM        \
 172        || FIXP->fx_r_type == BFD_RELOC_AVR_LO8_LDI_PM_NEG    \
 173        || FIXP->fx_r_type == BFD_RELOC_AVR_HI8_LDI_PM_NEG    \
 174        || FIXP->fx_r_type == BFD_RELOC_AVR_HH8_LDI_PM_NEG    \
 175        || FIXP->fx_r_type == BFD_RELOC_AVR_8_LO              \
 176        || FIXP->fx_r_type == BFD_RELOC_AVR_8_HI              \
 177        || FIXP->fx_r_type == BFD_RELOC_AVR_8_HLO             \
 178        || FIXP->fx_r_type == BFD_RELOC_AVR_16_PM)            \
 179       && FIXP->fx_addsy != NULL                              \
 180       && FIXP->fx_subsy == NULL)                             \
 181     {                                                        \
 182       symbol_mark_used_in_reloc (FIXP->fx_addsy);            \
 183       goto SKIP;                                             \
 184     }
 185
 186 /* This macro is evaluated for any fixup with a fx_subsy that
 187    fixup_segment cannot reduce to a number.  If the macro returns
 188    false an error will be reported. */
 189 #define TC_VALIDATE_FIX_SUB(fix, seg)   avr_validate_fix_sub (fix)
 190 extern int avr_validate_fix_sub (struct fix *);
 191
 192 /* This target is buggy, and sets fix size too large.  */
 193 #define TC_FX_SIZE_SLACK(FIX) 2
 194
 195 /* AVR instructions are 2 or 4 bytes long.  */
 196 #define DWARF2_LINE_MIN_INSN_LENGTH     2
 197
 198 /* 32 bits pseudo-addresses are used on AVR.  */
 199 #define DWARF2_ADDR_SIZE(bfd) 4
 200
 201 /* Enable cfi directives.  */
 202 #define TARGET_USE_CFIPOP 1
 203
 204 /* The stack grows down, and is only byte aligned.  */
 205 #define DWARF2_CIE_DATA_ALIGNMENT -1
 206
 207 /* Define the column that represents the PC.  */
 208 #define DWARF2_DEFAULT_RETURN_COLUMN  36
 209
 210 /* Define a hook to setup initial CFI state.  */
 211 extern void tc_cfi_frame_initial_instructions (void);
 212 #define tc_cfi_frame_initial_instructions tc_cfi_frame_initial_instructions
 213
 214 /* The difference between same-section symbols may be affected by linker
 215    relaxation, so do not resolve such expressions in the assembler.  */
 216 #define md_allow_local_subtract(l,r,s) avr_allow_local_subtract (l, r, s)
 217 extern bfd_boolean avr_allow_local_subtract (expressionS *, expressionS *, segT);
 218
 219 #define elf_tc_final_processing         avr_elf_final_processing
 220 extern void avr_elf_final_processing (void);
 221
 222 #define md_pre_output_hook avr_pre_output_hook ()
 223 extern void avr_pre_output_hook (void);
 224
 225 #define md_undefined_symbol avr_undefined_symbol
 226 extern symbolS* avr_undefined_symbol (char*);
 227
 228 #define md_post_relax_hook avr_post_relax_hook ()
 229 extern void avr_post_relax_hook (void);
 230
 231 #define HANDLE_ALIGN(fragP) avr_handle_align (fragP)
 232 extern void avr_handle_align (fragS *);
 233
 234 struct avr_frag_data
 235 {
 236   unsigned is_org : 1;
 237   unsigned is_align : 1;
 238   unsigned has_fill : 1;
 239
 240   char fill;
 241   offsetT alignment;
 242   unsigned int prev_opcode;
 243 };
 244 #define TC_FRAG_TYPE                    struct avr_frag_data
 245 #define TC_FRAG_INIT(frag, max_bytes)   avr_frag_init (frag)
 246 extern void avr_frag_init (fragS *);