1 /* ctfc.h - Declarations and definitions related to the CTF container.
2 Copyright (C) 2019-2023 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 /* This file defines the data structures and functions used by the compiler
21 to generate the CTF debug info. The definitions below are compiler internal
22 representations and closely reflect the CTF format requirements in <ctf.h>.
23
24 The contents of the CTF container are used eventually for emission of both
25 CTF (ctfout.cc) and BTF debug info (btfout.cc), as the two type debug formats
26 are close cousins. */
27
28 #ifndef GCC_CTFC_H
29 #define GCC_CTFC_H 1
30
31 #include "config.h"
32 #include "system.h"
33 #include "tree.h"
34 #include "fold-const.h"
35 #include "dwarf2ctf.h"
36 #include "ctf.h"
37 #include "btf.h"
38
39 /* Invalid CTF type ID definition. */
40
41 #define CTF_NULL_TYPEID 0
42
43 /* Value to start generating the CTF type ID from. */
44
45 #define CTF_INIT_TYPEID 1
46
47 /* CTF type ID. */
48
49 typedef uint64_t ctf_id_t;
50
51 /* CTF string table element (list node). */
52
53 typedef struct GTY ((chain_next ("%h.cts_next"))) ctf_string
54 {
55 const char * cts_str; /* CTF string. */
56 struct ctf_string * cts_next; /* A list node. */
57 } ctf_string_t;
58
59 /* Internal representation of CTF string table. */
60
61 typedef struct GTY (()) ctf_strtable
62 {
63 ctf_string_t * ctstab_head; /* Head str ptr. */
64 ctf_string_t * ctstab_tail; /* Tail. new str appended to tail. */
65 int ctstab_num; /* Number of strings in the table. */
66 size_t ctstab_len; /* Size of string table in bytes. */
67 const char * ctstab_estr; /* Empty string "". */
68 } ctf_strtable_t;
69
70 /* Encoding information for integers, floating-point values etc. The flags
71 field will contain values appropriate for the type defined in <ctf.h>. */
72
73 typedef struct GTY (()) ctf_encoding
74 {
75 unsigned int cte_format; /* Data format (CTF_INT_* or CTF_FP_* flags). */
76 unsigned int cte_offset; /* Offset of value in bits. */
77 unsigned int cte_bits; /* Size of storage in bits. */
78 } ctf_encoding_t;
79
80 /* Array information for CTF generation. */
81
82 typedef struct GTY (()) ctf_arinfo
83 {
84 ctf_id_t ctr_contents; /* Type of array contents. */
85 ctf_id_t ctr_index; /* Type of array index. */
86 unsigned int ctr_nelems; /* Number of elements. */
87 } ctf_arinfo_t;
88
89 /* Function information for CTF generation. */
90
91 typedef struct GTY (()) ctf_funcinfo
92 {
93 ctf_id_t ctc_return; /* Function return type. */
94 unsigned int ctc_argc; /* Number of typed arguments to function. */
95 unsigned int ctc_flags; /* Function attributes (see below). */
96 } ctf_funcinfo_t;
97
98 typedef struct GTY (()) ctf_sliceinfo
99 {
100 unsigned int cts_type; /* Reference CTF type. */
101 unsigned short cts_offset; /* Offset in bits of the first bit. */
102 unsigned short cts_bits; /* Size in bits. */
103 } ctf_sliceinfo_t;
104
105 /* CTF type representation internal to the compiler. It closely reflects the
106 ctf_type_t type node in <ctf.h> except the GTY (()) tags. */
107
108 typedef struct GTY (()) ctf_itype
109 {
110 uint32_t ctti_name; /* Reference to name in string table. */
111 uint32_t ctti_info; /* Encoded kind, variant length (see below). */
112 union GTY ((desc ("0")))
113 {
114 uint32_t GTY ((tag ("0"))) _size;/* Size of entire type in bytes. */
115 uint32_t GTY ((tag ("1"))) _type;/* Reference to another type. */
116 } _u;
117 uint32_t ctti_lsizehi; /* High 32 bits of type size in bytes. */
118 uint32_t ctti_lsizelo; /* Low 32 bits of type size in bytes. */
119 } ctf_itype_t;
120
121 #define ctti_size _u._size
122 #define ctti_type _u._type
123
124 /* Function arguments end with varargs. */
125
126 #define CTF_FUNC_VARARG 0x1
127
128 /* Struct/union/enum member definition for CTF generation. */
129
130 typedef struct GTY ((chain_next ("%h.dmd_next"))) ctf_dmdef
131 {
132 const char * dmd_name; /* Name of this member. */
133 ctf_id_t dmd_type; /* Type of this member (for sou). */
134 uint32_t dmd_name_offset; /* Offset of the name in str table. */
135 uint64_t dmd_offset; /* Offset of this member in bits (for sou). */
136 HOST_WIDE_INT dmd_value; /* Value of this member (for enum). */
137 struct ctf_dmdef * dmd_next; /* A list node. */
138 } ctf_dmdef_t;
139
140 #define ctf_dmd_list_next(elem) ((ctf_dmdef_t *)((elem)->dmd_next))
141
142 /* Function Argument. */
143
144 typedef struct GTY (()) ctf_func_arg
145 {
146 ctf_id_t farg_type; /* Type identifier of the argument. */
147 const char * farg_name; /* Name of the argument. */
148 uint32_t farg_name_offset; /* Offset of the name in str table. */
149 struct ctf_func_arg * farg_next;/* A list node. */
150 } ctf_func_arg_t;
151
152 #define ctf_farg_list_next(elem) ((ctf_func_arg_t *)((elem)->farg_next))
153
154 /* Type definition for CTF generation. */
155
156 struct GTY ((for_user)) ctf_dtdef
157 {
158 dw_die_ref dtd_key; /* Type key for hashing. */
159 const char * dtd_name; /* Name associated with definition (if any). */
160 ctf_id_t dtd_type; /* Type identifier for this definition. */
161 ctf_itype_t dtd_data; /* Type node. */
162 bool from_global_func; /* Whether this type was added from a global
163 function. */
164 uint32_t linkage; /* Used in function types. 0=local, 1=global. */
165 bool dtd_enum_unsigned; /* Enum signedness. */
166 union GTY ((desc ("ctf_dtu_d_union_selector (&%1)")))
167 {
168 /* struct, union, or enum. */
169 ctf_dmdef_t * GTY ((tag ("CTF_DTU_D_MEMBERS"))) dtu_members;
170 /* array. */
171 ctf_arinfo_t GTY ((tag ("CTF_DTU_D_ARRAY"))) dtu_arr;
172 /* integer or float. */
173 ctf_encoding_t GTY ((tag ("CTF_DTU_D_ENCODING"))) dtu_enc;
174 /* function. */
175 ctf_func_arg_t * GTY ((tag ("CTF_DTU_D_ARGUMENTS"))) dtu_argv;
176 /* slice. */
177 ctf_sliceinfo_t GTY ((tag ("CTF_DTU_D_SLICE"))) dtu_slice;
178 } dtd_u;
179 };
180
181 typedef struct ctf_dtdef ctf_dtdef_t;
182
183 /* Variable definition for CTF generation. */
184
185 struct GTY ((for_user)) ctf_dvdef
186 {
187 dw_die_ref dvd_key; /* DWARF DIE corresponding to the variable. */
188 const char * dvd_name; /* Name associated with variable. */
189 uint32_t dvd_name_offset; /* Offset of the name in str table. */
190 unsigned int dvd_visibility; /* External visibility. 0=static,1=global. */
191 ctf_id_t dvd_type; /* Type of variable. */
192 };
193
194 typedef struct ctf_dvdef ctf_dvdef_t;
195
196 typedef ctf_dvdef_t * ctf_dvdef_ref;
197 typedef ctf_dtdef_t * ctf_dtdef_ref;
198
199 /* Location information for CTF Types and CTF Variables. */
200
201 typedef struct GTY (()) ctf_srcloc
202 {
203 const char * ctsloc_file;
204 unsigned int ctsloc_line;
205 unsigned int ctsloc_col;
206 } ctf_srcloc_t;
207
208 typedef ctf_srcloc_t * ctf_srcloc_ref;
209
210 /* Helper enum and api for the GTY machinery to work on union dtu_d. */
211
212 enum ctf_dtu_d_union_enum {
213 CTF_DTU_D_MEMBERS,
214 CTF_DTU_D_ARRAY,
215 CTF_DTU_D_ENCODING,
216 CTF_DTU_D_ARGUMENTS,
217 CTF_DTU_D_SLICE
218 };
219
220 enum ctf_dtu_d_union_enum
221 ctf_dtu_d_union_selector (ctf_dtdef_ref);
222
223 struct ctfc_dtd_hasher : ggc_ptr_hash <ctf_dtdef_t>
224 {
225 typedef ctf_dtdef_ref compare_type;
226
227 static hashval_t hash (ctf_dtdef_ref);
228 static bool equal (ctf_dtdef_ref, ctf_dtdef_ref);
229 };
230
231 inline hashval_t
232 ctfc_dtd_hasher::hash (ctf_dtdef_ref dtd)
233 {
234 return htab_hash_pointer (dtd->dtd_key);
235 }
236
237 inline bool
238 ctfc_dtd_hasher::equal (ctf_dtdef_ref dtd, ctf_dtdef_ref dtd2)
239 {
240 return (dtd->dtd_key == dtd2->dtd_key);
241 }
242
243 struct ctfc_dvd_hasher : ggc_ptr_hash <ctf_dvdef_t>
244 {
245 typedef ctf_dvdef_ref compare_type;
246
247 static hashval_t hash (ctf_dvdef_ref);
248 static bool equal (ctf_dvdef_ref, ctf_dvdef_ref);
249 };
250
251 inline hashval_t
252 ctfc_dvd_hasher::hash (ctf_dvdef_ref dvd)
253 {
254 return htab_hash_pointer (dvd->dvd_key);
255 }
256
257 inline bool
258 ctfc_dvd_hasher::equal (ctf_dvdef_ref dvd, ctf_dvdef_ref dvd2)
259 {
260 return (dvd->dvd_key == dvd2->dvd_key);
261 }
262
263 /* CTF container structure.
264 It is the context passed around when generating ctf debug info. There is
265 one container per translation unit. */
266
267 typedef struct GTY (()) ctf_container
268 {
269 /* CTF Preamble. */
270 unsigned short ctfc_magic;
271 unsigned char ctfc_version;
272 unsigned char ctfc_flags;
273 uint32_t ctfc_cuname_offset;
274
275 /* CTF types. */
276 hash_table <ctfc_dtd_hasher> * GTY (()) ctfc_types;
277 /* CTF variables. */
278 hash_table <ctfc_dvd_hasher> * GTY (()) ctfc_vars;
279 /* CTF variables to be ignored. */
280 hash_table <ctfc_dvd_hasher> * GTY (()) ctfc_ignore_vars;
281
282 /* CTF string table. */
283 ctf_strtable_t ctfc_strtable;
284 /* Auxilliary string table. At this time, used for keeping func arg names
285 for BTF. */
286 ctf_strtable_t ctfc_aux_strtable;
287
288 uint64_t ctfc_num_types;
289 uint64_t ctfc_num_stypes;
290 uint64_t ctfc_num_global_funcs;
291 uint64_t ctfc_num_global_objts;
292
293 /* Number of vlen bytes - the variable length portion after ctf_type_t and
294 ctf_stype_t in the CTF section. This is used to calculate the offsets in
295 the CTF header. */
296 uint64_t ctfc_num_vlen_bytes;
297
298 /* Next CTF type id to assign. */
299 ctf_id_t ctfc_nextid;
300
301 /* Specify an explicit length of 0 so that the GC marking routines steer
302 clear of marking the CTF vars and CTF types twice. These lists below do
303 not own the pointed to objects, they simply hold references to them. */
304
305 /* List of pre-processed CTF Variables. CTF requires that the variables
306 appear in the sorted order of their names. */
307 ctf_dvdef_t ** GTY ((length ("0"))) ctfc_vars_list;
308 /* Count of pre-processed CTF Variables in the list. */
309 uint64_t ctfc_vars_list_count;
310 /* List of pre-processed CTF types. CTF requires that a shared type must
311 appear before the type that uses it. For the compiler, this means types
312 are emitted in sorted order of their type IDs. */
313 ctf_dtdef_t ** GTY ((length ("0"))) ctfc_types_list;
314 /* List of CTF function types for global functions. The order of global
315 function entries in the CTF funcinfo section is undefined by the
316 compiler. */
317 ctf_dtdef_t ** GTY ((length ("0"))) ctfc_gfuncs_list;
318 /* List of CTF variables at global scope. The order of global object entries
319 in the CTF objinfo section is undefined by the compiler. */
320 ctf_dvdef_t ** GTY ((length ("0"))) ctfc_gobjts_list;
321
322 /* Following members are for debugging only. They do not add functional
323 value to the task of CTF creation. These can be cleaned up once CTF
324 generation stabilizes. */
325
326 /* Keep a count of the number of bytes dumped in asm for debugging
327 purposes. */
328 uint64_t ctfc_numbytes_asm;
329 /* Total length of all strings in CTF. */
330 size_t ctfc_strlen;
331 /* Total length of all strings in aux string table. */
332 size_t ctfc_aux_strlen;
333
334 } ctf_container_t;
335
336 /* Markers for which string table from the CTF container to use. */
337
338 #define CTF_STRTAB 0 /* CTF string table. */
339 #define CTF_AUX_STRTAB 1 /* CTF auxilliary string table. */
340
341 typedef ctf_container_t * ctf_container_ref;
342
343 extern GTY (()) ctf_container_ref tu_ctfc;
344
345 extern void ctfc_delete_container (ctf_container_ref);
346
347 /* If the next ctf type id is still set to the init value, no ctf records to
348 report. */
349 extern bool ctfc_is_empty_container (ctf_container_ref);
350
351 /* Get the total number of CTF types in the container. */
352
353 extern unsigned int ctfc_get_num_ctf_types (ctf_container_ref);
354
355 /* Get the total number of CTF variables in the container. */
356
357 extern unsigned int ctfc_get_num_ctf_vars (ctf_container_ref);
358
359 /* Get reference to the CTF string table or the CTF auxilliary
360 string table. */
361
362 extern ctf_strtable_t * ctfc_get_strtab (ctf_container_ref, int);
363
364 /* Get the length of the specified string table in the CTF container. */
365
366 extern size_t ctfc_get_strtab_len (ctf_container_ref, int);
367
368 /* Get the number of bytes to represent the variable length portion of all CTF
369 types in the CTF container. */
370
371 extern size_t ctfc_get_num_vlen_bytes (ctf_container_ref);
372
373 /* The compiler demarcates whether types are visible at top-level scope or not.
374 The only example so far of a type not visible at top-level scope is slices.
375 CTF_ADD_NONROOT is used to indicate the latter. */
376 #define CTF_ADD_NONROOT 0 /* CTF type only visible in nested scope. */
377 #define CTF_ADD_ROOT 1 /* CTF type visible at top-level scope. */
378
379 /* These APIs allow to initialize and finalize the CTF machinery and
380 to add types to the CTF container associated to the current
381 translation unit. Used in dwarf2ctf.cc. */
382
383 extern void ctf_init (void);
384 extern void ctf_output (const char * filename);
385 extern void ctf_finalize (void);
386
387 extern void btf_output (const char * filename);
388 extern void btf_init_postprocess (void);
389 extern void btf_finalize (void);
390
391 extern ctf_container_ref ctf_get_tu_ctfc (void);
392
393 extern bool ctf_type_exists (ctf_container_ref, dw_die_ref, ctf_id_t *);
394
395 extern void ctf_add_cuname (ctf_container_ref, const char *);
396
397 extern ctf_dtdef_ref ctf_dtd_lookup (const ctf_container_ref ctfc,
398 dw_die_ref die);
399 extern ctf_dvdef_ref ctf_dvd_lookup (const ctf_container_ref ctfc,
400 dw_die_ref die);
401 extern bool ctf_dvd_ignore_lookup (const ctf_container_ref ctfc,
402 dw_die_ref die);
403
404 extern const char * ctf_add_string (ctf_container_ref, const char *,
405 uint32_t *, int);
406
407 extern ctf_id_t ctf_add_reftype (ctf_container_ref, uint32_t, ctf_id_t,
408 uint32_t, dw_die_ref);
409 extern ctf_id_t ctf_add_enum (ctf_container_ref, uint32_t, const char *,
410 HOST_WIDE_INT, bool, dw_die_ref);
411 extern ctf_id_t ctf_add_slice (ctf_container_ref, uint32_t, ctf_id_t,
412 uint32_t, uint32_t, dw_die_ref);
413 extern ctf_id_t ctf_add_float (ctf_container_ref, uint32_t, const char *,
414 const ctf_encoding_t *, dw_die_ref);
415 extern ctf_id_t ctf_add_integer (ctf_container_ref, uint32_t, const char *,
416 const ctf_encoding_t *, dw_die_ref);
417 extern ctf_id_t ctf_add_unknown (ctf_container_ref, uint32_t, const char *,
418 const ctf_encoding_t *, dw_die_ref);
419 extern ctf_id_t ctf_add_pointer (ctf_container_ref, uint32_t, ctf_id_t,
420 dw_die_ref);
421 extern ctf_id_t ctf_add_array (ctf_container_ref, uint32_t,
422 const ctf_arinfo_t *, dw_die_ref);
423 extern ctf_id_t ctf_add_forward (ctf_container_ref, uint32_t, const char *,
424 uint32_t, dw_die_ref);
425 extern ctf_id_t ctf_add_typedef (ctf_container_ref, uint32_t, const char *,
426 ctf_id_t, dw_die_ref);
427 extern ctf_id_t ctf_add_function (ctf_container_ref, uint32_t, const char *,
428 const ctf_funcinfo_t *, dw_die_ref, bool, int);
429 extern ctf_id_t ctf_add_sou (ctf_container_ref, uint32_t, const char *,
430 uint32_t, size_t, dw_die_ref);
431
432 extern int ctf_add_enumerator (ctf_container_ref, ctf_id_t, const char *,
433 HOST_WIDE_INT, dw_die_ref);
434 extern int ctf_add_member_offset (ctf_container_ref, dw_die_ref, const char *,
435 ctf_id_t, uint64_t);
436 extern int ctf_add_function_arg (ctf_container_ref, dw_die_ref,
437 const char *, ctf_id_t);
438 extern int ctf_add_variable (ctf_container_ref, const char *, ctf_id_t,
439 dw_die_ref, unsigned int, dw_die_ref);
440
441 extern ctf_id_t ctf_lookup_tree_type (ctf_container_ref, const tree);
442 extern ctf_id_t get_btf_id (ctf_id_t);
443
444 /* CTF section does not emit location information; at this time, location
445 information is needed for BTF CO-RE use-cases. */
446
447 extern int ctfc_get_dtd_srcloc (ctf_dtdef_ref, ctf_srcloc_ref);
448 extern int ctfc_get_dvd_srcloc (ctf_dvdef_ref, ctf_srcloc_ref);
449
450 #endif /* GCC_CTFC_H */