1 /* This file is tc-arm.h
2 Copyright (C) 1994-2021 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_COFF
50 # define ARM_BI_ENDIAN
51 # if defined TE_PE
52 # if defined TE_WINCE
53 # define TARGET_FORMAT (target_big_endian ? "pe-arm-wince-big" : "pe-arm-wince-little")
54 # else
55 # define TARGET_FORMAT (target_big_endian ? "pe-arm-big" : "pe-arm-little")
56 # endif
57 # else
58 # define TARGET_FORMAT (target_big_endian ? "coff-arm-big" : "coff-arm-little")
59 # endif
60 #elif defined OBJ_ELF
61 # define ARM_BI_ENDIAN
62 # define TARGET_FORMAT elf32_arm_target_format ()
63 #endif
64
65 /* We support double slash line-comments for compatibility with the ARM AArch64 Assembler. */
66 #define DOUBLESLASH_LINE_COMMENTS
67
68 /* We conditionally support labels without a colon. */
69 #define LABELS_WITHOUT_COLONS codecomposer_syntax
70 extern bool codecomposer_syntax;
71
72 #define tc_symbol_chars arm_symbol_chars
73 extern const char arm_symbol_chars[];
74
75 #define TC_FORCE_RELOCATION(FIX) arm_force_relocation (FIX)
76
77 extern unsigned int arm_frag_max_var (struct frag *);
78 #define md_frag_max_var arm_frag_max_var
79
80 #define md_relax_frag(segment, fragp, stretch) \
81 arm_relax_frag (segment, fragp, stretch)
82 extern int arm_relax_frag (asection *, struct frag *, long);
83
84 #define md_optimize_expr(l,o,r) arm_optimize_expr (l, o, r)
85 extern bool arm_optimize_expr (expressionS *, operatorT, expressionS *);
86
87 #define md_cleanup() arm_cleanup ()
88
89 #define md_start_line_hook() arm_start_line_hook ()
90
91 #define TC_START_LABEL_WITHOUT_COLON(NUL_CHAR, NEXT_CHAR) \
92 tc_start_label_without_colon ()
93 extern bool tc_start_label_without_colon (void);
94
95 #define tc_frob_label(S) arm_frob_label (S)
96
97 /* We also need to mark assembler created symbols: */
98 #define tc_frob_fake_label(S) arm_frob_label (S)
99
100 #ifdef OBJ_ELF
101 #define md_end arm_md_end
102 extern void arm_md_end (void);
103 bool arm_is_eabi (void);
104
105 #define md_post_relax_hook arm_md_post_relax ()
106 extern void arm_md_post_relax (void);
107 #endif
108
109 /* NOTE: The fake label creation in stabs.c:s_stab_generic() has
110 deliberately not been updated to mark assembler created stabs
111 symbols as Thumb. */
112
113 #define TC_FIX_TYPE int
114 #define TC_INIT_FIX_DATA(FIX) ((FIX)->tc_fix_data = 0)
115
116 /* We need to keep some local information on symbols. */
117
118 #define TC_SYMFIELD_TYPE unsigned int
119 #define ARM_GET_FLAG(s) (*symbol_get_tc (s))
120 #define ARM_SET_FLAG(s,v) (*symbol_get_tc (s) |= (v))
121 #define ARM_RESET_FLAG(s,v) (*symbol_get_tc (s) &= ~(v))
122
123 #define ARM_FLAG_THUMB (1 << 0) /* The symbol is a Thumb symbol rather than an Arm symbol. */
124 #define ARM_FLAG_INTERWORK (1 << 1) /* The symbol is attached to code that supports interworking. */
125 #define THUMB_FLAG_FUNC (1 << 2) /* The symbol is attached to the start of a Thumb function. */
126
127 #define ARM_IS_THUMB(s) (ARM_GET_FLAG (s) & ARM_FLAG_THUMB)
128 #define ARM_IS_INTERWORK(s) (ARM_GET_FLAG (s) & ARM_FLAG_INTERWORK)
129
130 #ifdef OBJ_ELF
131
132 /* For ELF objects THUMB_IS_FUNC is inferred from
133 ARM_IS_THUMB and the function type. */
134 #define THUMB_IS_FUNC(s) \
135 ((s) != NULL \
136 && ((arm_is_eabi () \
137 && (ARM_IS_THUMB (s)) \
138 && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)) \
139 || (ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)))
140
141 #define ARM_IS_FUNC(s) \
142 (((s) != NULL \
143 && arm_is_eabi () \
144 && !(ARM_IS_THUMB (s)) \
145 /* && !(THUMB_FLAG_FUNC & ARM_GET_FLAG (s)) \ */ \
146 && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION)))
147
148
149 #else
150
151 #define THUMB_IS_FUNC(s) ((s) && ARM_GET_FLAG (s) & THUMB_FLAG_FUNC)
152 #define ARM_IS_FUNC(s) (!THUMB_IS_FUNC (s) \
153 && (s) && (symbol_get_bfdsym (s)->flags & BSF_FUNCTION))
154 #endif
155
156 #define ARM_SET_THUMB(s,t) ((t) ? ARM_SET_FLAG (s, ARM_FLAG_THUMB) : ARM_RESET_FLAG (s, ARM_FLAG_THUMB))
157 #define ARM_SET_INTERWORK(s,t) ((t) ? ARM_SET_FLAG (s, ARM_FLAG_INTERWORK) : ARM_RESET_FLAG (s, ARM_FLAG_INTERWORK))
158 #define THUMB_SET_FUNC(s,t) ((t) ? ARM_SET_FLAG (s, THUMB_FLAG_FUNC) : ARM_RESET_FLAG (s, THUMB_FLAG_FUNC))
159
160 void arm_copy_symbol_attributes (symbolS *, symbolS *);
161
162 #ifndef TC_COPY_SYMBOL_ATTRIBUTES
163 #define TC_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
164 (arm_copy_symbol_attributes (DEST, SRC))
165 #endif
166
167 #define TC_START_LABEL(STR, NUL_CHAR, NEXT_CHAR) \
168 (NEXT_CHAR == ':' || (NEXT_CHAR == '/' && arm_data_in_code ()))
169 #define tc_canonicalize_symbol_name(str) arm_canonicalize_symbol_name (str);
170 #define obj_adjust_symtab() arm_adjust_symtab ()
171
172 #define LISTING_HEADER "ARM GAS "
173
174 #define OPTIONAL_REGISTER_PREFIX '%'
175
176 #define LOCAL_LABEL(name) (name[0] == '.' && name[1] == 'L')
177 #define LOCAL_LABELS_FB 1
178
179 /* This expression evaluates to true if the relocation is for a local
180 object for which we still want to do the relocation at runtime.
181 False if we are willing to perform this relocation while building
182 the .o file. GOTOFF does not need to be checked here because it is
183 not pcrel. I am not sure if some of the others are ever used with
184 pcrel, but it is easier to be safe than sorry. */
185
186 #define TC_FORCE_RELOCATION_LOCAL(FIX) \
187 (GENERIC_FORCE_RELOCATION_LOCAL (FIX) \
188 || (FIX)->fx_r_type == BFD_RELOC_ARM_GOT32 \
189 || (FIX)->fx_r_type == BFD_RELOC_32 \
190 || ((FIX)->fx_addsy != NULL \
191 && S_IS_WEAK ((FIX)->fx_addsy)))
192
193 /* Force output of R_ARM_REL32 relocations against thumb function symbols.
194 This is needed to ensure the low bit is handled correctly. */
195 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG) \
196 (GENERIC_FORCE_RELOCATION_SUB_SAME (FIX, SEG) \
197 || THUMB_IS_FUNC ((FIX)->fx_addsy))
198
199 #define TC_FORCE_RELOCATION_ABS(FIX) \
200 (((FIX)->fx_pcrel \
201 && (FIX)->fx_r_type != BFD_RELOC_32 \
202 && (FIX)->fx_r_type != BFD_RELOC_ARM_GOT32) \
203 || TC_FORCE_RELOCATION(FIX))
204
205 #define TC_CONS_FIX_NEW cons_fix_new_arm
206
207 #define MAX_MEM_ALIGNMENT_BYTES 6
208 #define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << MAX_MEM_ALIGNMENT_BYTES) - 1)
209
210 /* For frags in code sections we need to record whether they contain
211 ARM code or THUMB code. This is that if they have to be aligned,
212 they can contain the correct type of no-op instruction. */
213 struct arm_frag_type
214 {
215 int thumb_mode;
216 #ifdef OBJ_ELF
217 /* If there is a mapping symbol at offset 0 in this frag,
218 it will be saved in FIRST_MAP. If there are any mapping
219 symbols in this frag, the last one will be saved in
220 LAST_MAP. */
221 symbolS *first_map, *last_map;
222 #endif
223 };
224
225 static inline int
arm_min(int am_p1,int am_p2)226 arm_min (int am_p1, int am_p2)
227 {
228 return am_p1 < am_p2 ? am_p1 : am_p2;
229 }
230
231 #define TC_FRAG_TYPE struct arm_frag_type
232 #define TC_FRAG_INIT(fragp, max_bytes) arm_init_frag (fragp, max_bytes)
233 #define TC_ALIGN_ZERO_IS_DEFAULT 1
234 #define HANDLE_ALIGN(fragp) arm_handle_align (fragp)
235 /* PR gas/19276: COFF/PE segment alignment is already handled in coff_frob_section(). */
236 #ifndef TE_PE
237 #define SUB_SEGMENT_ALIGN(SEG, FRCHAIN) \
238 ((!(FRCHAIN)->frch_next && subseg_text_p (SEG)) \
239 ? arm_min (2, get_recorded_alignment (SEG)) : 0)
240 #endif
241
242 #define md_do_align(N, FILL, LEN, MAX, LABEL) \
243 if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg)) \
244 { \
245 arm_frag_align_code (N, MAX); \
246 goto LABEL; \
247 }
248
249 #define DWARF2_LINE_MIN_INSN_LENGTH 2
250
251 /* The lr register is r14. */
252 #define DWARF2_DEFAULT_RETURN_COLUMN 14
253
254 /* Registers are generally saved at negative offsets to the CFA. */
255 #define DWARF2_CIE_DATA_ALIGNMENT (-4)
256
257 /* State variables for predication block handling. */
258 enum pred_state
259 {
260 OUTSIDE_PRED_BLOCK, MANUAL_PRED_BLOCK, AUTOMATIC_PRED_BLOCK
261 };
262 enum pred_type {
263 SCALAR_PRED, VECTOR_PRED
264 };
265 struct current_pred
266 {
267 int mask;
268 enum pred_state state;
269 int cc;
270 int block_length;
271 char *insn;
272 int state_handled;
273 int warn_deprecated;
274 int insn_cond;
275 enum pred_type type;
276 };
277
278 #ifdef OBJ_ELF
279 # define obj_frob_symbol(sym, punt) armelf_frob_symbol ((sym), & (punt))
280 # define md_elf_section_change_hook() arm_elf_change_section ()
281 # define md_elf_section_type(str, len) arm_elf_section_type (str, len)
282 # define GLOBAL_OFFSET_TABLE_NAME "_GLOBAL_OFFSET_TABLE_"
283 # define TC_SEGMENT_INFO_TYPE struct arm_segment_info_type
284
285 /* This is not really an alignment operation, but it's something we
286 need to do at the same time: whenever we are figuring out the
287 alignment for data, we should check whether a $d symbol is
288 necessary. */
289 # define md_cons_align(nbytes) mapping_state (MAP_DATA)
290
291 enum mstate
292 {
293 MAP_UNDEFINED = 0, /* Must be zero, for seginfo in new sections. */
294 MAP_DATA,
295 MAP_ARM,
296 MAP_THUMB
297 };
298
299 void mapping_state (enum mstate);
300
301 struct arm_segment_info_type
302 {
303 enum mstate mapstate;
304
305 /* Bit N indicates that an R_ARM_NONE relocation has been output for
306 __aeabi_unwind_cpp_prN already if set. This enables dependencies to be
307 emitted only once per section, to save unnecessary bloat. */
308 unsigned int marked_pr_dependency;
309
310 struct current_pred current_pred;
311 };
312
313 /* We want .cfi_* pseudo-ops for generating unwind info. */
314 #define TARGET_USE_CFIPOP 1
315
316 /* CFI hooks. */
317 #define tc_regname_to_dw2regnum tc_arm_regname_to_dw2regnum
318 #define tc_cfi_frame_initial_instructions tc_arm_frame_initial_instructions
319
320 #else /* Not OBJ_ELF. */
321 #define GLOBAL_OFFSET_TABLE_NAME "__GLOBAL_OFFSET_TABLE_"
322 #endif
323
324 #if defined OBJ_ELF || defined OBJ_COFF
325
326 # define EXTERN_FORCE_RELOC 1
327 # define tc_fix_adjustable(FIX) arm_fix_adjustable (FIX)
328 #endif
329
330 #ifdef OBJ_ELF
331 /* Values passed to md_apply_fix don't include the symbol value. */
332 # define MD_APPLY_SYM_VALUE(FIX) arm_apply_sym_value (FIX, this_segment)
333 #endif
334
335 #ifdef OBJ_COFF
336 # define TC_VALIDATE_FIX(FIX, SEGTYPE, LABEL) arm_validate_fix (FIX)
337 /* Values passed to md_apply_fix don't include the symbol value. */
338 # define MD_APPLY_SYM_VALUE(FIX) 0
339 #endif
340
341 #define MD_PCREL_FROM_SECTION(F,S) md_pcrel_from_section(F,S)
342
343 extern void arm_frag_align_code (int, int);
344 extern void arm_validate_fix (struct fix *);
345 extern const char * elf32_arm_target_format (void);
346 extern void arm_elf_change_section (void);
347 extern int arm_force_relocation (struct fix *);
348 extern void arm_cleanup (void);
349 extern void arm_start_line_hook (void);
350 extern void arm_frob_label (symbolS *);
351 extern bool arm_data_in_code (void);
352 extern char * arm_canonicalize_symbol_name (char *);
353 extern void arm_adjust_symtab (void);
354 extern void armelf_frob_symbol (symbolS *, int *);
355 extern void cons_fix_new_arm (fragS *, int, int, expressionS *,
356 bfd_reloc_code_real_type);
357 extern void arm_init_frag (struct frag *, int);
358 extern void arm_handle_align (struct frag *);
359 extern bool arm_fix_adjustable (struct fix *);
360 extern int arm_elf_section_type (const char *, size_t);
361 extern int tc_arm_regname_to_dw2regnum (char *regname);
362 extern void tc_arm_frame_initial_instructions (void);
363
364 #ifdef TE_PE
365
366 #define O_secrel O_md1
367
368 #define TC_DWARF2_EMIT_OFFSET tc_pe_dwarf2_emit_offset
369 void tc_pe_dwarf2_emit_offset (symbolS *, unsigned int);
370
371 #endif /* TE_PE */
372
373 #ifdef OBJ_ELF
374 #define CONVERT_SYMBOLIC_ATTRIBUTE(name) arm_convert_symbolic_attribute (name)
375 extern int arm_convert_symbolic_attribute (const char *);
376 extern int arm_apply_sym_value (struct fix *, segT);
377 #endif
378
379 #define tc_comment_chars arm_comment_chars
380 extern char arm_comment_chars[];
381
382 #define tc_line_separator_chars arm_line_separator_chars
383 extern char arm_line_separator_chars[];
384
385 #define TC_EQUAL_IN_INSN(c, s) arm_tc_equal_in_insn ((c), (s))
386 extern bool arm_tc_equal_in_insn (int, char *);
387
388 #define TC_LARGEST_EXPONENT_IS_NORMAL(PRECISION) \
389 arm_is_largest_exponent_ok ((PRECISION))
390 int arm_is_largest_exponent_ok (int precision);
391