1 /* ctfc.h - Declarations and definitions related to the CTF container.
2 Copyright (C) 2019,2021 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.c) and BTF debug info (btfout.c), 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 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 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 union GTY ((desc ("ctf_dtu_d_union_selector (&%1)")))
165 {
166 /* struct, union, or enum. */
167 ctf_dmdef_t * GTY ((tag ("CTF_DTU_D_MEMBERS"))) dtu_members;
168 /* array. */
169 ctf_arinfo_t GTY ((tag ("CTF_DTU_D_ARRAY"))) dtu_arr;
170 /* integer or float. */
171 ctf_encoding_t GTY ((tag ("CTF_DTU_D_ENCODING"))) dtu_enc;
172 /* function. */
173 ctf_func_arg_t * GTY ((tag ("CTF_DTU_D_ARGUMENTS"))) dtu_argv;
174 /* slice. */
175 ctf_sliceinfo_t GTY ((tag ("CTF_DTU_D_SLICE"))) dtu_slice;
176 } dtd_u;
177 };
178
179 typedef struct ctf_dtdef ctf_dtdef_t;
180
181 /* Variable definition for CTF generation. */
182
183 struct GTY ((for_user)) ctf_dvdef
184 {
185 dw_die_ref dvd_key; /* DWARF DIE corresponding to the variable. */
186 const char * dvd_name; /* Name associated with variable. */
187 uint32_t dvd_name_offset; /* Offset of the name in str table. */
188 unsigned int dvd_visibility; /* External visibility. 0=static,1=global. */
189 ctf_id_t dvd_type; /* Type of variable. */
190 };
191
192 typedef struct ctf_dvdef ctf_dvdef_t;
193
194 typedef ctf_dvdef_t * ctf_dvdef_ref;
195 typedef ctf_dtdef_t * ctf_dtdef_ref;
196
197 /* Location information for CTF Types and CTF Variables. */
198
199 typedef struct GTY (()) ctf_srcloc
200 {
201 const char * ctsloc_file;
202 unsigned int ctsloc_line;
203 unsigned int ctsloc_col;
204 } ctf_srcloc_t;
205
206 typedef ctf_srcloc_t * ctf_srcloc_ref;
207
208 /* Helper enum and api for the GTY machinery to work on union dtu_d. */
209
210 enum ctf_dtu_d_union_enum {
211 CTF_DTU_D_MEMBERS,
212 CTF_DTU_D_ARRAY,
213 CTF_DTU_D_ENCODING,
214 CTF_DTU_D_ARGUMENTS,
215 CTF_DTU_D_SLICE
216 };
217
218 enum ctf_dtu_d_union_enum
219 ctf_dtu_d_union_selector (ctf_dtdef_ref);
220
221 struct ctfc_dtd_hasher : ggc_ptr_hash <ctf_dtdef_t>
222 {
223 typedef ctf_dtdef_ref compare_type;
224
225 static hashval_t hash (ctf_dtdef_ref);
226 static bool equal (ctf_dtdef_ref, ctf_dtdef_ref);
227 };
228
229 inline hashval_t
hash(ctf_dtdef_ref dtd)230 ctfc_dtd_hasher::hash (ctf_dtdef_ref dtd)
231 {
232 return htab_hash_pointer (dtd->dtd_key);
233 }
234
235 inline bool
equal(ctf_dtdef_ref dtd,ctf_dtdef_ref dtd2)236 ctfc_dtd_hasher::equal (ctf_dtdef_ref dtd, ctf_dtdef_ref dtd2)
237 {
238 return (dtd->dtd_key == dtd2->dtd_key);
239 }
240
241 struct ctfc_dvd_hasher : ggc_ptr_hash <ctf_dvdef_t>
242 {
243 typedef ctf_dvdef_ref compare_type;
244
245 static hashval_t hash (ctf_dvdef_ref);
246 static bool equal (ctf_dvdef_ref, ctf_dvdef_ref);
247 };
248
249 inline hashval_t
hash(ctf_dvdef_ref dvd)250 ctfc_dvd_hasher::hash (ctf_dvdef_ref dvd)
251 {
252 return htab_hash_pointer (dvd->dvd_key);
253 }
254
255 inline bool
equal(ctf_dvdef_ref dvd,ctf_dvdef_ref dvd2)256 ctfc_dvd_hasher::equal (ctf_dvdef_ref dvd, ctf_dvdef_ref dvd2)
257 {
258 return (dvd->dvd_key == dvd2->dvd_key);
259 }
260
261 /* CTF container structure.
262 It is the context passed around when generating ctf debug info. There is
263 one container per translation unit. */
264
265 typedef struct GTY (()) ctf_container
266 {
267 /* CTF Preamble. */
268 unsigned short ctfc_magic;
269 unsigned char ctfc_version;
270 unsigned char ctfc_flags;
271 uint32_t ctfc_cuname_offset;
272
273 /* CTF types. */
274 hash_table <ctfc_dtd_hasher> * GTY (()) ctfc_types;
275 /* CTF variables. */
276 hash_table <ctfc_dvd_hasher> * GTY (()) ctfc_vars;
277
278 /* CTF string table. */
279 ctf_strtable_t ctfc_strtable;
280 /* Auxilliary string table. At this time, used for keeping func arg names
281 for BTF. */
282 ctf_strtable_t ctfc_aux_strtable;
283
284 uint64_t ctfc_num_types;
285 uint64_t ctfc_num_stypes;
286 uint64_t ctfc_num_global_funcs;
287 uint64_t ctfc_num_global_objts;
288
289 /* Number of vlen bytes - the variable length portion after ctf_type_t and
290 ctf_stype_t in the CTF section. This is used to calculate the offsets in
291 the CTF header. */
292 uint64_t ctfc_num_vlen_bytes;
293
294 /* Next CTF type id to assign. */
295 ctf_id_t ctfc_nextid;
296
297 /* Specify an explicit length of 0 so that the GC marking routines steer
298 clear of marking the CTF vars and CTF types twice. These lists below do
299 not own the pointed to objects, they simply hold references to them. */
300
301 /* List of pre-processed CTF Variables. CTF requires that the variables
302 appear in the sorted order of their names. */
303 ctf_dvdef_t ** GTY ((length ("0"))) ctfc_vars_list;
304 /* List of pre-processed CTF types. CTF requires that a shared type must
305 appear before the type that uses it. For the compiler, this means types
306 are emitted in sorted order of their type IDs. */
307 ctf_dtdef_t ** GTY ((length ("0"))) ctfc_types_list;
308 /* List of CTF function types for global functions. The order of global
309 function entries in the CTF funcinfo section is undefined by the
310 compiler. */
311 ctf_dtdef_t ** GTY ((length ("0"))) ctfc_gfuncs_list;
312 /* List of CTF variables at global scope. The order of global object entries
313 in the CTF objinfo section is undefined by the compiler. */
314 ctf_dvdef_t ** GTY ((length ("0"))) ctfc_gobjts_list;
315
316 /* Following members are for debugging only. They do not add functional
317 value to the task of CTF creation. These can be cleaned up once CTF
318 generation stabilizes. */
319
320 /* Keep a count of the number of bytes dumped in asm for debugging
321 purposes. */
322 uint64_t ctfc_numbytes_asm;
323 /* Total length of all strings in CTF. */
324 size_t ctfc_strlen;
325 /* Total length of all strings in aux string table. */
326 size_t ctfc_aux_strlen;
327
328 } ctf_container_t;
329
330 /* Markers for which string table from the CTF container to use. */
331
332 #define CTF_STRTAB 0 /* CTF string table. */
333 #define CTF_AUX_STRTAB 1 /* CTF auxilliary string table. */
334
335 typedef ctf_container_t * ctf_container_ref;
336
337 extern GTY (()) ctf_container_ref tu_ctfc;
338
339 extern void ctfc_delete_container (ctf_container_ref);
340
341 /* If the next ctf type id is still set to the init value, no ctf records to
342 report. */
343 extern bool ctfc_is_empty_container (ctf_container_ref);
344
345 /* Get the total number of CTF types in the container. */
346
347 extern unsigned int ctfc_get_num_ctf_types (ctf_container_ref);
348
349 /* Get the total number of CTF variables in the container. */
350
351 extern unsigned int ctfc_get_num_ctf_vars (ctf_container_ref);
352
353 /* Get reference to the CTF string table or the CTF auxilliary
354 string table. */
355
356 extern ctf_strtable_t * ctfc_get_strtab (ctf_container_ref, int);
357
358 /* Get the length of the specified string table in the CTF container. */
359
360 extern size_t ctfc_get_strtab_len (ctf_container_ref, int);
361
362 /* Get the number of bytes to represent the variable length portion of all CTF
363 types in the CTF container. */
364
365 extern size_t ctfc_get_num_vlen_bytes (ctf_container_ref);
366
367 /* The compiler demarcates whether types are visible at top-level scope or not.
368 The only example so far of a type not visible at top-level scope is slices.
369 CTF_ADD_NONROOT is used to indicate the latter. */
370 #define CTF_ADD_NONROOT 0 /* CTF type only visible in nested scope. */
371 #define CTF_ADD_ROOT 1 /* CTF type visible at top-level scope. */
372
373 /* These APIs allow to initialize and finalize the CTF machinery and
374 to add types to the CTF container associated to the current
375 translation unit. Used in dwarf2ctf.c. */
376
377 extern void ctf_init (void);
378 extern void ctf_output (const char * filename);
379 extern void ctf_finalize (void);
380
381 extern void btf_output (const char * filename);
382 extern void btf_init_postprocess (void);
383 extern void btf_finalize (void);
384
385 extern ctf_container_ref ctf_get_tu_ctfc (void);
386
387 extern bool ctf_type_exists (ctf_container_ref, dw_die_ref, ctf_id_t *);
388
389 extern void ctf_add_cuname (ctf_container_ref, const char *);
390
391 extern ctf_dtdef_ref ctf_dtd_lookup (const ctf_container_ref ctfc,
392 dw_die_ref die);
393 extern ctf_dvdef_ref ctf_dvd_lookup (const ctf_container_ref ctfc,
394 dw_die_ref die);
395
396 extern const char * ctf_add_string (ctf_container_ref, const char *,
397 uint32_t *, int);
398
399 extern ctf_id_t ctf_add_reftype (ctf_container_ref, uint32_t, ctf_id_t,
400 uint32_t, dw_die_ref);
401 extern ctf_id_t ctf_add_enum (ctf_container_ref, uint32_t, const char *,
402 HOST_WIDE_INT, dw_die_ref);
403 extern ctf_id_t ctf_add_slice (ctf_container_ref, uint32_t, ctf_id_t,
404 uint32_t, uint32_t, dw_die_ref);
405 extern ctf_id_t ctf_add_float (ctf_container_ref, uint32_t, const char *,
406 const ctf_encoding_t *, dw_die_ref);
407 extern ctf_id_t ctf_add_integer (ctf_container_ref, uint32_t, const char *,
408 const ctf_encoding_t *, dw_die_ref);
409 extern ctf_id_t ctf_add_unknown (ctf_container_ref, uint32_t, const char *,
410 const ctf_encoding_t *, dw_die_ref);
411 extern ctf_id_t ctf_add_pointer (ctf_container_ref, uint32_t, ctf_id_t,
412 dw_die_ref);
413 extern ctf_id_t ctf_add_array (ctf_container_ref, uint32_t,
414 const ctf_arinfo_t *, dw_die_ref);
415 extern ctf_id_t ctf_add_forward (ctf_container_ref, uint32_t, const char *,
416 uint32_t, dw_die_ref);
417 extern ctf_id_t ctf_add_typedef (ctf_container_ref, uint32_t, const char *,
418 ctf_id_t, dw_die_ref);
419 extern ctf_id_t ctf_add_function (ctf_container_ref, uint32_t, const char *,
420 const ctf_funcinfo_t *, dw_die_ref, bool);
421 extern ctf_id_t ctf_add_sou (ctf_container_ref, uint32_t, const char *,
422 uint32_t, size_t, dw_die_ref);
423
424 extern int ctf_add_enumerator (ctf_container_ref, ctf_id_t, const char *,
425 HOST_WIDE_INT, dw_die_ref);
426 extern int ctf_add_member_offset (ctf_container_ref, dw_die_ref, const char *,
427 ctf_id_t, uint64_t);
428 extern int ctf_add_function_arg (ctf_container_ref, dw_die_ref,
429 const char *, ctf_id_t);
430 extern int ctf_add_variable (ctf_container_ref, const char *, ctf_id_t,
431 dw_die_ref, unsigned int);
432
433 extern ctf_id_t ctf_lookup_tree_type (ctf_container_ref, const tree);
434 extern ctf_id_t get_btf_id (ctf_id_t);
435
436 /* CTF section does not emit location information; at this time, location
437 information is needed for BTF CO-RE use-cases. */
438
439 extern int ctfc_get_dtd_srcloc (ctf_dtdef_ref, ctf_srcloc_ref);
440 extern int ctfc_get_dvd_srcloc (ctf_dvdef_ref, ctf_srcloc_ref);
441
442 #endif /* GCC_CTFC_H */
443