1 /* This file is tc-arm.h
2 Copyright (C) 1994-2023 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 TARGET_ARCH bfd_arch_arm
32
33 #define DIFF_EXPR_OK
34
35 #ifdef LITTLE_ENDIAN
36 #undef LITTLE_ENDIAN
37 #endif
38
39 #ifdef BIG_ENDIAN
40 #undef BIG_ENDIAN
41 #endif
42
43 #define LITTLE_ENDIAN 1234
44 #define BIG_ENDIAN 4321
45
46 struct fix;
47
48 #if defined OBJ_COFF
49 # define ARM_BI_ENDIAN
50 # if defined TE_PE
51 # if defined TE_WINCE
52 # define TARGET_FORMAT (target_big_endian ? "pe-arm-wince-big" : "pe-arm-wince-little")
53 # else
54 # define TARGET_FORMAT (target_big_endian ? "pe-arm-big" : "pe-arm-little")
55 # endif
56 # else
57 # define TARGET_FORMAT (target_big_endian ? "coff-arm-big" : "coff-arm-little")
58 # endif
59 #elif defined OBJ_ELF
60 # define ARM_BI_ENDIAN
61 # define TARGET_FORMAT elf32_arm_target_format ()
62 #endif
63
64 /* We support double slash line-comments for compatibility with the ARM AArch64 Assembler. */
65 #define DOUBLESLASH_LINE_COMMENTS
66
67 /* We conditionally support labels without a colon. */
68 #define LABELS_WITHOUT_COLONS codecomposer_syntax
69 extern bool codecomposer_syntax;
70
71 #define tc_symbol_chars arm_symbol_chars
72 extern const char arm_symbol_chars[];
73
74 #define TC_FORCE_RELOCATION(FIX) arm_force_relocation (FIX)
75
76 extern unsigned int arm_frag_max_var (struct frag *);
77 #define md_frag_max_var arm_frag_max_var
78
79 #define md_relax_frag(segment, fragp, stretch) \
80 arm_relax_frag (segment, fragp, stretch)
81 extern int arm_relax_frag (asection *, struct frag *, long);
82
83 #define md_optimize_expr(l,o,r) arm_optimize_expr (l, o, r)
84 extern bool arm_optimize_expr (expressionS *, operatorT, expressionS *);
85
86 #define md_cleanup() arm_cleanup ()
87
88 #define md_start_line_hook() arm_start_line_hook ()
89
90 #define TC_START_LABEL_WITHOUT_COLON(NUL_CHAR, NEXT_CHAR) \
91 tc_start_label_without_colon ()
92 extern bool tc_start_label_without_colon (void);
93
94 #define tc_frob_label(S) arm_frob_label (S)
95
96 /* We also need to mark assembler created symbols: */
97 #define tc_frob_fake_label(S) arm_frob_label (S)
98
99 #ifdef OBJ_ELF
100 #define md_finish arm_md_finish
101 extern void arm_md_finish (void);
102 bool arm_is_eabi (void);
103
104 #define md_post_relax_hook arm_md_post_relax ()
105 extern void arm_md_post_relax (void);
106 #endif
107
108 /* NOTE: The fake label creation in stabs.c:s_stab_generic() has
109 deliberately not been updated to mark assembler created stabs
110 symbols as Thumb. */
111
112 #define TC_FIX_TYPE int
113 #define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)
114
115 /* We need to keep some local information on symbols. */
116
117 #define TC_SYMFIELD_TYPE unsigned int
118 #define ARM_GET_FLAG(s) (*symbol_get_tc (s))
119 #define ARM_SET_FLAG(s,v) (*symbol_get_tc (s) |= (v))
120 #define ARM_RESET_FLAG(s,v) (*symbol_get_tc (s) &= ~(v))
121
122 #define ARM_FLAG_THUMB (1 << 0) /* The symbol is a Thumb symbol rather than an Arm symbol. */
123 #define ARM_FLAG_INTERWORK (1 << 1) /* The symbol is attached to code that supports interworking. */
124 #define THUMB_FLAG_FUNC (1 << 2) /* The symbol is attached to the start of a Thumb function. */
125
126 #define ARM_IS_THUMB(s) (ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
127 #define ARM_IS_INTERWORK(s) (ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)
128
129 #ifdef OBJ_ELF
130
131 /* For ELF objects THUMB_IS_FUNC is inferred from
132 ARM_IS_THUMB and the function type. */
133 #define THUMB_IS_FUNC(s) \
134 ((s) != NULL \
135 && ((arm_is_eabi () \
136 && (ARM_IS_THUMB (s)) \
137 && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)) \
138 || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))
139
140 #define ARM_IS_FUNC(s) \
141 (((s) != NULL \
142 && arm_is_eabi () \
143 && !(ARM_IS_THUMB (s)) \
144 /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */ \
145 && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))
146
147
148 #else
149
150 #define THUMB_IS_FUNC(s) ((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
151 #define ARM_IS_FUNC(s) (!THUMB_IS_FUNC (s) \
152 && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
153 #endif
154
155 #define ARM_SET_THUMB(s,t) ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB) : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
156 #define ARM_SET_INTERWORK(s,t) ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
157 #define THUMB_SET_FUNC(s,t) ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC) : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))
158
159 void arm_copy_symbol_attributes (symbolS *, symbolS *);
160
161 #ifndef TC_COPY_SYMBOL_ATTRIBUTES
162 #define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
163 (arm_copy_symbol_attributes (DEST, SRC))
164 #endif
165
166 #define TC_START_LABEL(STR, NUL_CHAR, NEXT_CHAR) \
167 (NEXT_CHAR == ':' || (NEXT_CHAR == '/' && arm_data_in_code ()))
168 #define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
169 #define obj_adjust_symtab() arm_adjust_symtab ()
170
171 #define LISTING_HEADER "ARM GAS "
172
173 #define OPTIONAL_REGISTER_PREFIX '%'
174
175 #define LOCAL_LABEL(name) (name[0] == '.' && name[1] == 'L')
176 #define LOCAL_LABELS_FB 1
177
178 /* This expression evaluates to true if the relocation is for a local
179 object for which we still want to do the relocation at runtime.
180 False if we are willing to perform this relocation while building
181 the .o file. GOTOFF does not need to be checked here because it is
182 not pcrel. I am not sure if some of the others are ever used with
183 pcrel, but it is easier to be safe than sorry. */
184
185 #define TC_FORCE_RELOCATION_LOCAL(FIX) \
186 (GENERIC_FORCE_RELOCATION_LOCAL (FIX) \
187 || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32 \
188 || (FIX)->fx_r_type == BFD_RELOC_32 \
189 || ((FIX)->fx_addsy != NULL \
190 && S_IS_WEAK ((FIX)->fx_addsy)))
191
192 /* Force output of R_ARM_REL32 relocations against thumb function symbols.
193 This is needed to ensure the low bit is handled correctly. */
194 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
195 (GENERIC_FORCE_RELOCATION_SUB_SAME (FIX, SEG) \
196 || THUMB_IS_FUNC ((FIX)->fx_addsy))
197
198 #define TC_FORCE_RELOCATION_ABS(FIX) \
199 (((FIX)->fx_pcrel \
200 && (FIX)->fx_r_type != BFD_RELOC_32 \
201 && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32) \
202 || TC_FORCE_RELOCATION(FIX))
203
204 #define TC_CONS_FIX_NEW cons_fix_new_arm
205
206 #define MAX_MEM_ALIGNMENT_BYTES 6
207 #define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)
208
209 /* For frags in code sections we need to record whether they contain
210 ARM code or THUMB code. This is that if they have to be aligned,
211 they can contain the correct type of no-op instruction. */
212 struct arm_frag_type
213 {
214 int thumb_mode;
215 #ifdef OBJ_ELF
216 /* If there is a mapping symbol at offset 0 in this frag,
217 it will be saved in FIRST_MAP. If there are any mapping
218 symbols in this frag, the last one will be saved in
219 LAST_MAP. */
220 symbolS *first_map, *last_map;
221 #endif
222 };
223
224 static inline int
225 arm_min (int am_p1, int am_p2)
226 {
227 return am_p1 < am_p2 ? am_p1 : am_p2;
228 }
229
230 #define TC_FRAG_TYPE struct arm_frag_type
231 #define TC_FRAG_INIT(fragp, max_bytes) arm_init_frag (fragp, max_bytes)
232 #define TC_ALIGN_ZERO_IS_DEFAULT 1
233 #define HANDLE_ALIGN(fragp) arm_handle_align (fragp)
234 /* PR gas/19276: COFF/PE segment alignment is already handled in coff_frob_section(). */
235 #ifndef TE_PE
236 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
237 ((!(FRCHAIN)->frch_next && subseg_text_p (SEG)) \
238 ? arm_min (2, get_recorded_alignment (SEG)) : 0)
239 #endif
240
241 #define md_do_align(N, FILL, LEN, MAX, LABEL) \
242 if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg)) \
243 { \
244 arm_frag_align_code (N, MAX); \
245 goto LABEL; \
246 }
247
248 #define DWARF2_LINE_MIN_INSN_LENGTH 2
249
250 /* The lr register is r14. */
251 #define DWARF2_DEFAULT_RETURN_COLUMN 14
252
253 /* Registers are generally saved at negative offsets to the CFA. */
254 #define DWARF2_CIE_DATA_ALIGNMENT (-4)
255
256 /* State variables for predication block handling. */
257 enum pred_state
258 {
259 OUTSIDE_PRED_BLOCK, MANUAL_PRED_BLOCK, AUTOMATIC_PRED_BLOCK
260 };
261 enum pred_type {
262 SCALAR_PRED, VECTOR_PRED
263 };
264 struct current_pred
265 {
266 int mask;
267 enum pred_state state;
268 int cc;
269 int block_length;
270 char *insn;
271 int state_handled;
272 int warn_deprecated;
273 int insn_cond;
274 enum pred_type type;
275 };
276
277 #ifdef OBJ_ELF
278 # define obj_frob_symbol(sym, punt) armelf_frob_symbol ((sym), & (punt))
279 # define md_elf_section_change_hook() arm_elf_change_section ()
280 # define md_elf_section_type(str, len) arm_elf_section_type (str, len)
281 # define GLOBAL_OFFSET_TABLE_NAME "_GLOBAL_OFFSET_TABLE_"
282 # define TC_SEGMENT_INFO_TYPE struct arm_segment_info_type
283
284 /* This is not really an alignment operation, but it's something we
285 need to do at the same time: whenever we are figuring out the
286 alignment for data, we should check whether a $d symbol is
287 necessary. */
288 # define md_cons_align(nbytes) mapping_state (MAP_DATA)
289
290 enum mstate
291 {
292 MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections. */
293 MAP_DATA,
294 MAP_ARM,
295 MAP_THUMB
296 };
297
298 void mapping_state (enum mstate);
299
300 struct arm_segment_info_type
301 {
302 enum mstate mapstate;
303
304 /* Bit N indicates that an R_ARM_NONE relocation has been output for
305 __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
306 emitted only once per section, to save unnecessary bloat. */
307 unsigned int marked_pr_dependency;
308
309 struct current_pred current_pred;
310 };
311
312 /* We want .cfi_* pseudo-ops for generating unwind info. */
313 #define TARGET_USE_CFIPOP 1
314
315 /* CFI hooks. */
316 #define tc_regname_to_dw2regnum tc_arm_regname_to_dw2regnum
317 #define tc_cfi_frame_initial_instructions tc_arm_frame_initial_instructions
318
319 #else /* Not OBJ_ELF. */
320 #define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
321 #endif
322
323 #if defined OBJ_ELF || defined OBJ_COFF
324
325 # define EXTERN_FORCE_RELOC 1
326 # define tc_fix_adjustable(FIX) arm_fix_adjustable (FIX)
327 #endif
328
329 #ifdef OBJ_ELF
330 /* Values passed to md_apply_fix don't include the symbol value. */
331 # define MD_APPLY_SYM_VALUE(FIX) arm_apply_sym_value (FIX, this_segment)
332 #endif
333
334 #ifdef OBJ_COFF
335 # define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL) arm_validate_fix (FIX)
336 /* Values passed to md_apply_fix don't include the symbol value. */
337 # define MD_APPLY_SYM_VALUE(FIX) 0
338 #endif
339
340 #define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)
341
342 extern void arm_frag_align_code (int, int);
343 extern void arm_validate_fix (struct fix *);
344 extern const char * elf32_arm_target_format (void);
345 extern void arm_elf_change_section (void);
346 extern int arm_force_relocation (struct fix *);
347 extern void arm_cleanup (void);
348 extern void arm_start_line_hook (void);
349 extern void arm_frob_label (symbolS *);
350 extern bool arm_data_in_code (void);
351 extern char * arm_canonicalize_symbol_name (char *);
352 extern void arm_adjust_symtab (void);
353 extern void armelf_frob_symbol (symbolS *, int *);
354 extern void cons_fix_new_arm (fragS *, int, int, expressionS *,
355 bfd_reloc_code_real_type);
356 extern void arm_init_frag (struct frag *, int);
357 extern void arm_handle_align (struct frag *);
358 extern bool arm_fix_adjustable (struct fix *);
359 extern int arm_elf_section_type (const char *, size_t);
360 extern int tc_arm_regname_to_dw2regnum (char *regname);
361 extern void tc_arm_frame_initial_instructions (void);
362
363 #ifdef TE_PE
364
365 #define O_secrel O_md1
366
367 #define TC_DWARF2_EMIT_OFFSET tc_pe_dwarf2_emit_offset
368 void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);
369
370 #endif /* TE_PE */
371
372 #ifdef OBJ_ELF
373 #define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
374 extern int arm_convert_symbolic_attribute (const char *);
375 extern int arm_apply_sym_value (struct fix *, segT);
376 #endif
377
378 #define tc_comment_chars arm_comment_chars
379 extern char arm_comment_chars[];
380
381 #define tc_line_separator_chars arm_line_separator_chars
382 extern char arm_line_separator_chars[];
383
384 #define TC_EQUAL_IN_INSN(c, s) arm_tc_equal_in_insn ((c), (s))
385 extern bool arm_tc_equal_in_insn (int, char *);
386
387 #define TC_LARGEST_EXPONENT_IS_NORMAL(PRECISION) \
388 arm_is_largest_exponent_ok ((PRECISION))
389 int arm_is_largest_exponent_ok (int precision);