Commit | Line | Data |
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4c2df51b | 1 | /* DWARF 2 location expression support for GDB. |
feb13ab0 | 2 | |
ecd75fc8 | 3 | Copyright (C) 2003-2014 Free Software Foundation, Inc. |
feb13ab0 | 4 | |
4c2df51b DJ |
5 | Contributed by Daniel Jacobowitz, MontaVista Software, Inc. |
6 | ||
7 | This file is part of GDB. | |
8 | ||
9 | This program is free software; you can redistribute it and/or modify | |
10 | it under the terms of the GNU General Public License as published by | |
a9762ec7 JB |
11 | the Free Software Foundation; either version 3 of the License, or |
12 | (at your option) any later version. | |
4c2df51b | 13 | |
a9762ec7 JB |
14 | This program is distributed in the hope that it will be useful, |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
4c2df51b DJ |
18 | |
19 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
4c2df51b DJ |
21 | |
22 | #include "defs.h" | |
23 | #include "ui-out.h" | |
24 | #include "value.h" | |
25 | #include "frame.h" | |
26 | #include "gdbcore.h" | |
27 | #include "target.h" | |
28 | #include "inferior.h" | |
a55cc764 DJ |
29 | #include "ax.h" |
30 | #include "ax-gdb.h" | |
e4adbba9 | 31 | #include "regcache.h" |
c3228f12 | 32 | #include "objfiles.h" |
93ad78a7 | 33 | #include "exceptions.h" |
edb3359d | 34 | #include "block.h" |
8e3b41a9 | 35 | #include "gdbcmd.h" |
4c2df51b | 36 | |
fa8f86ff | 37 | #include "dwarf2.h" |
4c2df51b DJ |
38 | #include "dwarf2expr.h" |
39 | #include "dwarf2loc.h" | |
e7802207 | 40 | #include "dwarf2-frame.h" |
4c2df51b | 41 | |
0e9f083f | 42 | #include <string.h> |
eff4f95e | 43 | #include "gdb_assert.h" |
4c2df51b | 44 | |
9eae7c52 TT |
45 | extern int dwarf2_always_disassemble; |
46 | ||
1632a688 JK |
47 | static void dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc, |
48 | const gdb_byte **start, size_t *length); | |
0936ad1d | 49 | |
8e3b41a9 JK |
50 | static const struct dwarf_expr_context_funcs dwarf_expr_ctx_funcs; |
51 | ||
1632a688 JK |
52 | static struct value *dwarf2_evaluate_loc_desc_full (struct type *type, |
53 | struct frame_info *frame, | |
54 | const gdb_byte *data, | |
56eb65bd SP |
55 | size_t size, |
56 | struct dwarf2_per_cu_data *per_cu, | |
1632a688 | 57 | LONGEST byte_offset); |
8cf6f0b1 | 58 | |
f664829e DE |
59 | /* Until these have formal names, we define these here. |
60 | ref: http://gcc.gnu.org/wiki/DebugFission | |
61 | Each entry in .debug_loc.dwo begins with a byte that describes the entry, | |
62 | and is then followed by data specific to that entry. */ | |
63 | ||
64 | enum debug_loc_kind | |
65 | { | |
66 | /* Indicates the end of the list of entries. */ | |
67 | DEBUG_LOC_END_OF_LIST = 0, | |
68 | ||
69 | /* This is followed by an unsigned LEB128 number that is an index into | |
70 | .debug_addr and specifies the base address for all following entries. */ | |
71 | DEBUG_LOC_BASE_ADDRESS = 1, | |
72 | ||
73 | /* This is followed by two unsigned LEB128 numbers that are indices into | |
74 | .debug_addr and specify the beginning and ending addresses, and then | |
75 | a normal location expression as in .debug_loc. */ | |
3771a44c DE |
76 | DEBUG_LOC_START_END = 2, |
77 | ||
78 | /* This is followed by an unsigned LEB128 number that is an index into | |
79 | .debug_addr and specifies the beginning address, and a 4 byte unsigned | |
80 | number that specifies the length, and then a normal location expression | |
81 | as in .debug_loc. */ | |
82 | DEBUG_LOC_START_LENGTH = 3, | |
f664829e DE |
83 | |
84 | /* An internal value indicating there is insufficient data. */ | |
85 | DEBUG_LOC_BUFFER_OVERFLOW = -1, | |
86 | ||
87 | /* An internal value indicating an invalid kind of entry was found. */ | |
88 | DEBUG_LOC_INVALID_ENTRY = -2 | |
89 | }; | |
90 | ||
b6807d98 TT |
91 | /* Helper function which throws an error if a synthetic pointer is |
92 | invalid. */ | |
93 | ||
94 | static void | |
95 | invalid_synthetic_pointer (void) | |
96 | { | |
97 | error (_("access outside bounds of object " | |
98 | "referenced via synthetic pointer")); | |
99 | } | |
100 | ||
f664829e DE |
101 | /* Decode the addresses in a non-dwo .debug_loc entry. |
102 | A pointer to the next byte to examine is returned in *NEW_PTR. | |
103 | The encoded low,high addresses are return in *LOW,*HIGH. | |
104 | The result indicates the kind of entry found. */ | |
105 | ||
106 | static enum debug_loc_kind | |
107 | decode_debug_loc_addresses (const gdb_byte *loc_ptr, const gdb_byte *buf_end, | |
108 | const gdb_byte **new_ptr, | |
109 | CORE_ADDR *low, CORE_ADDR *high, | |
110 | enum bfd_endian byte_order, | |
111 | unsigned int addr_size, | |
112 | int signed_addr_p) | |
113 | { | |
114 | CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1)); | |
115 | ||
116 | if (buf_end - loc_ptr < 2 * addr_size) | |
117 | return DEBUG_LOC_BUFFER_OVERFLOW; | |
118 | ||
119 | if (signed_addr_p) | |
120 | *low = extract_signed_integer (loc_ptr, addr_size, byte_order); | |
121 | else | |
122 | *low = extract_unsigned_integer (loc_ptr, addr_size, byte_order); | |
123 | loc_ptr += addr_size; | |
124 | ||
125 | if (signed_addr_p) | |
126 | *high = extract_signed_integer (loc_ptr, addr_size, byte_order); | |
127 | else | |
128 | *high = extract_unsigned_integer (loc_ptr, addr_size, byte_order); | |
129 | loc_ptr += addr_size; | |
130 | ||
131 | *new_ptr = loc_ptr; | |
132 | ||
133 | /* A base-address-selection entry. */ | |
134 | if ((*low & base_mask) == base_mask) | |
135 | return DEBUG_LOC_BASE_ADDRESS; | |
136 | ||
137 | /* An end-of-list entry. */ | |
138 | if (*low == 0 && *high == 0) | |
139 | return DEBUG_LOC_END_OF_LIST; | |
140 | ||
3771a44c | 141 | return DEBUG_LOC_START_END; |
f664829e DE |
142 | } |
143 | ||
144 | /* Decode the addresses in .debug_loc.dwo entry. | |
145 | A pointer to the next byte to examine is returned in *NEW_PTR. | |
146 | The encoded low,high addresses are return in *LOW,*HIGH. | |
147 | The result indicates the kind of entry found. */ | |
148 | ||
149 | static enum debug_loc_kind | |
150 | decode_debug_loc_dwo_addresses (struct dwarf2_per_cu_data *per_cu, | |
151 | const gdb_byte *loc_ptr, | |
152 | const gdb_byte *buf_end, | |
153 | const gdb_byte **new_ptr, | |
3771a44c DE |
154 | CORE_ADDR *low, CORE_ADDR *high, |
155 | enum bfd_endian byte_order) | |
f664829e | 156 | { |
9fccedf7 | 157 | uint64_t low_index, high_index; |
f664829e DE |
158 | |
159 | if (loc_ptr == buf_end) | |
160 | return DEBUG_LOC_BUFFER_OVERFLOW; | |
161 | ||
162 | switch (*loc_ptr++) | |
163 | { | |
164 | case DEBUG_LOC_END_OF_LIST: | |
165 | *new_ptr = loc_ptr; | |
166 | return DEBUG_LOC_END_OF_LIST; | |
167 | case DEBUG_LOC_BASE_ADDRESS: | |
168 | *low = 0; | |
169 | loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &high_index); | |
170 | if (loc_ptr == NULL) | |
171 | return DEBUG_LOC_BUFFER_OVERFLOW; | |
172 | *high = dwarf2_read_addr_index (per_cu, high_index); | |
173 | *new_ptr = loc_ptr; | |
174 | return DEBUG_LOC_BASE_ADDRESS; | |
3771a44c | 175 | case DEBUG_LOC_START_END: |
f664829e DE |
176 | loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &low_index); |
177 | if (loc_ptr == NULL) | |
178 | return DEBUG_LOC_BUFFER_OVERFLOW; | |
179 | *low = dwarf2_read_addr_index (per_cu, low_index); | |
180 | loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &high_index); | |
181 | if (loc_ptr == NULL) | |
182 | return DEBUG_LOC_BUFFER_OVERFLOW; | |
183 | *high = dwarf2_read_addr_index (per_cu, high_index); | |
184 | *new_ptr = loc_ptr; | |
3771a44c DE |
185 | return DEBUG_LOC_START_END; |
186 | case DEBUG_LOC_START_LENGTH: | |
187 | loc_ptr = gdb_read_uleb128 (loc_ptr, buf_end, &low_index); | |
188 | if (loc_ptr == NULL) | |
189 | return DEBUG_LOC_BUFFER_OVERFLOW; | |
190 | *low = dwarf2_read_addr_index (per_cu, low_index); | |
191 | if (loc_ptr + 4 > buf_end) | |
192 | return DEBUG_LOC_BUFFER_OVERFLOW; | |
193 | *high = *low; | |
194 | *high += extract_unsigned_integer (loc_ptr, 4, byte_order); | |
195 | *new_ptr = loc_ptr + 4; | |
196 | return DEBUG_LOC_START_LENGTH; | |
f664829e DE |
197 | default: |
198 | return DEBUG_LOC_INVALID_ENTRY; | |
199 | } | |
200 | } | |
201 | ||
8cf6f0b1 | 202 | /* A function for dealing with location lists. Given a |
0d53c4c4 DJ |
203 | symbol baton (BATON) and a pc value (PC), find the appropriate |
204 | location expression, set *LOCEXPR_LENGTH, and return a pointer | |
205 | to the beginning of the expression. Returns NULL on failure. | |
206 | ||
207 | For now, only return the first matching location expression; there | |
208 | can be more than one in the list. */ | |
209 | ||
8cf6f0b1 TT |
210 | const gdb_byte * |
211 | dwarf2_find_location_expression (struct dwarf2_loclist_baton *baton, | |
212 | size_t *locexpr_length, CORE_ADDR pc) | |
0d53c4c4 | 213 | { |
ae0d2f24 | 214 | struct objfile *objfile = dwarf2_per_cu_objfile (baton->per_cu); |
f7fd4728 | 215 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
e17a4113 | 216 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
ae0d2f24 | 217 | unsigned int addr_size = dwarf2_per_cu_addr_size (baton->per_cu); |
d4a087c7 | 218 | int signed_addr_p = bfd_get_sign_extend_vma (objfile->obfd); |
8edfa926 | 219 | /* Adjust base_address for relocatable objects. */ |
9aa1f1e3 | 220 | CORE_ADDR base_offset = dwarf2_per_cu_text_offset (baton->per_cu); |
8edfa926 | 221 | CORE_ADDR base_address = baton->base_address + base_offset; |
f664829e | 222 | const gdb_byte *loc_ptr, *buf_end; |
0d53c4c4 DJ |
223 | |
224 | loc_ptr = baton->data; | |
225 | buf_end = baton->data + baton->size; | |
226 | ||
227 | while (1) | |
228 | { | |
f664829e DE |
229 | CORE_ADDR low = 0, high = 0; /* init for gcc -Wall */ |
230 | int length; | |
231 | enum debug_loc_kind kind; | |
232 | const gdb_byte *new_ptr = NULL; /* init for gcc -Wall */ | |
233 | ||
234 | if (baton->from_dwo) | |
235 | kind = decode_debug_loc_dwo_addresses (baton->per_cu, | |
236 | loc_ptr, buf_end, &new_ptr, | |
3771a44c | 237 | &low, &high, byte_order); |
d4a087c7 | 238 | else |
f664829e DE |
239 | kind = decode_debug_loc_addresses (loc_ptr, buf_end, &new_ptr, |
240 | &low, &high, | |
241 | byte_order, addr_size, | |
242 | signed_addr_p); | |
243 | loc_ptr = new_ptr; | |
244 | switch (kind) | |
1d6edc3c | 245 | { |
f664829e | 246 | case DEBUG_LOC_END_OF_LIST: |
1d6edc3c JK |
247 | *locexpr_length = 0; |
248 | return NULL; | |
f664829e DE |
249 | case DEBUG_LOC_BASE_ADDRESS: |
250 | base_address = high + base_offset; | |
251 | continue; | |
3771a44c DE |
252 | case DEBUG_LOC_START_END: |
253 | case DEBUG_LOC_START_LENGTH: | |
f664829e DE |
254 | break; |
255 | case DEBUG_LOC_BUFFER_OVERFLOW: | |
256 | case DEBUG_LOC_INVALID_ENTRY: | |
257 | error (_("dwarf2_find_location_expression: " | |
258 | "Corrupted DWARF expression.")); | |
259 | default: | |
260 | gdb_assert_not_reached ("bad debug_loc_kind"); | |
1d6edc3c | 261 | } |
b5758fe4 | 262 | |
bed911e5 DE |
263 | /* Otherwise, a location expression entry. |
264 | If the entry is from a DWO, don't add base address: the entry is | |
265 | from .debug_addr which has absolute addresses. */ | |
266 | if (! baton->from_dwo) | |
267 | { | |
268 | low += base_address; | |
269 | high += base_address; | |
270 | } | |
0d53c4c4 | 271 | |
e17a4113 | 272 | length = extract_unsigned_integer (loc_ptr, 2, byte_order); |
0d53c4c4 DJ |
273 | loc_ptr += 2; |
274 | ||
e18b2753 JK |
275 | if (low == high && pc == low) |
276 | { | |
277 | /* This is entry PC record present only at entry point | |
278 | of a function. Verify it is really the function entry point. */ | |
279 | ||
280 | struct block *pc_block = block_for_pc (pc); | |
281 | struct symbol *pc_func = NULL; | |
282 | ||
283 | if (pc_block) | |
284 | pc_func = block_linkage_function (pc_block); | |
285 | ||
286 | if (pc_func && pc == BLOCK_START (SYMBOL_BLOCK_VALUE (pc_func))) | |
287 | { | |
288 | *locexpr_length = length; | |
289 | return loc_ptr; | |
290 | } | |
291 | } | |
292 | ||
0d53c4c4 DJ |
293 | if (pc >= low && pc < high) |
294 | { | |
295 | *locexpr_length = length; | |
296 | return loc_ptr; | |
297 | } | |
298 | ||
299 | loc_ptr += length; | |
300 | } | |
301 | } | |
302 | ||
4c2df51b DJ |
303 | /* This is the baton used when performing dwarf2 expression |
304 | evaluation. */ | |
305 | struct dwarf_expr_baton | |
306 | { | |
307 | struct frame_info *frame; | |
17ea53c3 | 308 | struct dwarf2_per_cu_data *per_cu; |
4c2df51b DJ |
309 | }; |
310 | ||
311 | /* Helper functions for dwarf2_evaluate_loc_desc. */ | |
312 | ||
4bc9efe1 | 313 | /* Using the frame specified in BATON, return the value of register |
0b2b0195 | 314 | REGNUM, treated as a pointer. */ |
4c2df51b | 315 | static CORE_ADDR |
b1370418 | 316 | dwarf_expr_read_addr_from_reg (void *baton, int dwarf_regnum) |
4c2df51b | 317 | { |
4c2df51b | 318 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
5e2b427d | 319 | struct gdbarch *gdbarch = get_frame_arch (debaton->frame); |
2ed3c037 | 320 | int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum); |
e4adbba9 | 321 | |
2ed3c037 | 322 | return address_from_register (regnum, debaton->frame); |
4c2df51b DJ |
323 | } |
324 | ||
0acf8b65 JB |
325 | /* Implement struct dwarf_expr_context_funcs' "get_reg_value" callback. */ |
326 | ||
327 | static struct value * | |
328 | dwarf_expr_get_reg_value (void *baton, struct type *type, int dwarf_regnum) | |
329 | { | |
330 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
331 | struct gdbarch *gdbarch = get_frame_arch (debaton->frame); | |
332 | int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum); | |
333 | ||
334 | return value_from_register (type, regnum, debaton->frame); | |
335 | } | |
336 | ||
4c2df51b DJ |
337 | /* Read memory at ADDR (length LEN) into BUF. */ |
338 | ||
339 | static void | |
852483bc | 340 | dwarf_expr_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
4c2df51b DJ |
341 | { |
342 | read_memory (addr, buf, len); | |
343 | } | |
344 | ||
345 | /* Using the frame specified in BATON, find the location expression | |
346 | describing the frame base. Return a pointer to it in START and | |
347 | its length in LENGTH. */ | |
348 | static void | |
0d45f56e | 349 | dwarf_expr_frame_base (void *baton, const gdb_byte **start, size_t * length) |
4c2df51b | 350 | { |
da62e633 AC |
351 | /* FIXME: cagney/2003-03-26: This code should be using |
352 | get_frame_base_address(), and then implement a dwarf2 specific | |
353 | this_base method. */ | |
4c2df51b | 354 | struct symbol *framefunc; |
4c2df51b | 355 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
c90a0773 HZ |
356 | struct block *bl = get_frame_block (debaton->frame, NULL); |
357 | ||
358 | if (bl == NULL) | |
359 | error (_("frame address is not available.")); | |
0d53c4c4 | 360 | |
edb3359d DJ |
361 | /* Use block_linkage_function, which returns a real (not inlined) |
362 | function, instead of get_frame_function, which may return an | |
363 | inlined function. */ | |
c90a0773 | 364 | framefunc = block_linkage_function (bl); |
0d53c4c4 | 365 | |
eff4f95e JG |
366 | /* If we found a frame-relative symbol then it was certainly within |
367 | some function associated with a frame. If we can't find the frame, | |
368 | something has gone wrong. */ | |
369 | gdb_assert (framefunc != NULL); | |
370 | ||
0936ad1d SS |
371 | dwarf_expr_frame_base_1 (framefunc, |
372 | get_frame_address_in_block (debaton->frame), | |
373 | start, length); | |
374 | } | |
375 | ||
f1e6e072 TT |
376 | /* Implement find_frame_base_location method for LOC_BLOCK functions using |
377 | DWARF expression for its DW_AT_frame_base. */ | |
378 | ||
379 | static void | |
380 | locexpr_find_frame_base_location (struct symbol *framefunc, CORE_ADDR pc, | |
381 | const gdb_byte **start, size_t *length) | |
382 | { | |
383 | struct dwarf2_locexpr_baton *symbaton = SYMBOL_LOCATION_BATON (framefunc); | |
384 | ||
385 | *length = symbaton->size; | |
386 | *start = symbaton->data; | |
387 | } | |
388 | ||
389 | /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior | |
390 | function uses DWARF expression for its DW_AT_frame_base. */ | |
391 | ||
392 | const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs = | |
393 | { | |
394 | locexpr_find_frame_base_location | |
395 | }; | |
396 | ||
397 | /* Implement find_frame_base_location method for LOC_BLOCK functions using | |
398 | DWARF location list for its DW_AT_frame_base. */ | |
399 | ||
400 | static void | |
401 | loclist_find_frame_base_location (struct symbol *framefunc, CORE_ADDR pc, | |
402 | const gdb_byte **start, size_t *length) | |
403 | { | |
404 | struct dwarf2_loclist_baton *symbaton = SYMBOL_LOCATION_BATON (framefunc); | |
405 | ||
406 | *start = dwarf2_find_location_expression (symbaton, length, pc); | |
407 | } | |
408 | ||
409 | /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior | |
410 | function uses DWARF location list for its DW_AT_frame_base. */ | |
411 | ||
412 | const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs = | |
413 | { | |
414 | loclist_find_frame_base_location | |
415 | }; | |
416 | ||
0936ad1d SS |
417 | static void |
418 | dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc, | |
0d45f56e | 419 | const gdb_byte **start, size_t *length) |
0936ad1d | 420 | { |
f1e6e072 | 421 | if (SYMBOL_BLOCK_OPS (framefunc) != NULL) |
0d53c4c4 | 422 | { |
f1e6e072 | 423 | const struct symbol_block_ops *ops_block = SYMBOL_BLOCK_OPS (framefunc); |
22c6caba | 424 | |
f1e6e072 | 425 | ops_block->find_frame_base_location (framefunc, pc, start, length); |
0d53c4c4 DJ |
426 | } |
427 | else | |
f1e6e072 | 428 | *length = 0; |
0d53c4c4 | 429 | |
1d6edc3c | 430 | if (*length == 0) |
8a3fe4f8 | 431 | error (_("Could not find the frame base for \"%s\"."), |
0d53c4c4 | 432 | SYMBOL_NATURAL_NAME (framefunc)); |
4c2df51b DJ |
433 | } |
434 | ||
e7802207 TT |
435 | /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for |
436 | the frame in BATON. */ | |
437 | ||
438 | static CORE_ADDR | |
439 | dwarf_expr_frame_cfa (void *baton) | |
440 | { | |
441 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
9a619af0 | 442 | |
e7802207 TT |
443 | return dwarf2_frame_cfa (debaton->frame); |
444 | } | |
445 | ||
8cf6f0b1 TT |
446 | /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for |
447 | the frame in BATON. */ | |
448 | ||
449 | static CORE_ADDR | |
450 | dwarf_expr_frame_pc (void *baton) | |
451 | { | |
452 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
453 | ||
454 | return get_frame_address_in_block (debaton->frame); | |
455 | } | |
456 | ||
4c2df51b DJ |
457 | /* Using the objfile specified in BATON, find the address for the |
458 | current thread's thread-local storage with offset OFFSET. */ | |
459 | static CORE_ADDR | |
460 | dwarf_expr_tls_address (void *baton, CORE_ADDR offset) | |
461 | { | |
462 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
17ea53c3 | 463 | struct objfile *objfile = dwarf2_per_cu_objfile (debaton->per_cu); |
4c2df51b | 464 | |
17ea53c3 | 465 | return target_translate_tls_address (objfile, offset); |
4c2df51b DJ |
466 | } |
467 | ||
3e43a32a MS |
468 | /* Call DWARF subroutine from DW_AT_location of DIE at DIE_OFFSET in |
469 | current CU (as is PER_CU). State of the CTX is not affected by the | |
470 | call and return. */ | |
5c631832 JK |
471 | |
472 | static void | |
b64f50a1 | 473 | per_cu_dwarf_call (struct dwarf_expr_context *ctx, cu_offset die_offset, |
8cf6f0b1 TT |
474 | struct dwarf2_per_cu_data *per_cu, |
475 | CORE_ADDR (*get_frame_pc) (void *baton), | |
476 | void *baton) | |
5c631832 JK |
477 | { |
478 | struct dwarf2_locexpr_baton block; | |
479 | ||
8b9737bf | 480 | block = dwarf2_fetch_die_loc_cu_off (die_offset, per_cu, get_frame_pc, baton); |
5c631832 JK |
481 | |
482 | /* DW_OP_call_ref is currently not supported. */ | |
483 | gdb_assert (block.per_cu == per_cu); | |
484 | ||
485 | dwarf_expr_eval (ctx, block.data, block.size); | |
486 | } | |
487 | ||
488 | /* Helper interface of per_cu_dwarf_call for dwarf2_evaluate_loc_desc. */ | |
489 | ||
490 | static void | |
b64f50a1 | 491 | dwarf_expr_dwarf_call (struct dwarf_expr_context *ctx, cu_offset die_offset) |
5c631832 JK |
492 | { |
493 | struct dwarf_expr_baton *debaton = ctx->baton; | |
494 | ||
37b50a69 | 495 | per_cu_dwarf_call (ctx, die_offset, debaton->per_cu, |
9e8b7a03 | 496 | ctx->funcs->get_frame_pc, ctx->baton); |
5c631832 JK |
497 | } |
498 | ||
8a9b8146 TT |
499 | /* Callback function for dwarf2_evaluate_loc_desc. */ |
500 | ||
501 | static struct type * | |
b64f50a1 JK |
502 | dwarf_expr_get_base_type (struct dwarf_expr_context *ctx, |
503 | cu_offset die_offset) | |
8a9b8146 TT |
504 | { |
505 | struct dwarf_expr_baton *debaton = ctx->baton; | |
506 | ||
507 | return dwarf2_get_die_type (die_offset, debaton->per_cu); | |
508 | } | |
509 | ||
8e3b41a9 JK |
510 | /* See dwarf2loc.h. */ |
511 | ||
ccce17b0 | 512 | unsigned int entry_values_debug = 0; |
8e3b41a9 JK |
513 | |
514 | /* Helper to set entry_values_debug. */ | |
515 | ||
516 | static void | |
517 | show_entry_values_debug (struct ui_file *file, int from_tty, | |
518 | struct cmd_list_element *c, const char *value) | |
519 | { | |
520 | fprintf_filtered (file, | |
521 | _("Entry values and tail call frames debugging is %s.\n"), | |
522 | value); | |
523 | } | |
524 | ||
525 | /* Find DW_TAG_GNU_call_site's DW_AT_GNU_call_site_target address. | |
526 | CALLER_FRAME (for registers) can be NULL if it is not known. This function | |
527 | always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */ | |
528 | ||
529 | static CORE_ADDR | |
530 | call_site_to_target_addr (struct gdbarch *call_site_gdbarch, | |
531 | struct call_site *call_site, | |
532 | struct frame_info *caller_frame) | |
533 | { | |
534 | switch (FIELD_LOC_KIND (call_site->target)) | |
535 | { | |
536 | case FIELD_LOC_KIND_DWARF_BLOCK: | |
537 | { | |
538 | struct dwarf2_locexpr_baton *dwarf_block; | |
539 | struct value *val; | |
540 | struct type *caller_core_addr_type; | |
541 | struct gdbarch *caller_arch; | |
542 | ||
543 | dwarf_block = FIELD_DWARF_BLOCK (call_site->target); | |
544 | if (dwarf_block == NULL) | |
545 | { | |
7cbd4a93 | 546 | struct bound_minimal_symbol msym; |
8e3b41a9 JK |
547 | |
548 | msym = lookup_minimal_symbol_by_pc (call_site->pc - 1); | |
549 | throw_error (NO_ENTRY_VALUE_ERROR, | |
550 | _("DW_AT_GNU_call_site_target is not specified " | |
551 | "at %s in %s"), | |
552 | paddress (call_site_gdbarch, call_site->pc), | |
7cbd4a93 | 553 | (msym.minsym == NULL ? "???" |
efd66ac6 | 554 | : MSYMBOL_PRINT_NAME (msym.minsym))); |
8e3b41a9 JK |
555 | |
556 | } | |
557 | if (caller_frame == NULL) | |
558 | { | |
7cbd4a93 | 559 | struct bound_minimal_symbol msym; |
8e3b41a9 JK |
560 | |
561 | msym = lookup_minimal_symbol_by_pc (call_site->pc - 1); | |
562 | throw_error (NO_ENTRY_VALUE_ERROR, | |
563 | _("DW_AT_GNU_call_site_target DWARF block resolving " | |
564 | "requires known frame which is currently not " | |
565 | "available at %s in %s"), | |
566 | paddress (call_site_gdbarch, call_site->pc), | |
7cbd4a93 | 567 | (msym.minsym == NULL ? "???" |
efd66ac6 | 568 | : MSYMBOL_PRINT_NAME (msym.minsym))); |
8e3b41a9 JK |
569 | |
570 | } | |
571 | caller_arch = get_frame_arch (caller_frame); | |
572 | caller_core_addr_type = builtin_type (caller_arch)->builtin_func_ptr; | |
573 | val = dwarf2_evaluate_loc_desc (caller_core_addr_type, caller_frame, | |
574 | dwarf_block->data, dwarf_block->size, | |
575 | dwarf_block->per_cu); | |
576 | /* DW_AT_GNU_call_site_target is a DWARF expression, not a DWARF | |
577 | location. */ | |
578 | if (VALUE_LVAL (val) == lval_memory) | |
579 | return value_address (val); | |
580 | else | |
581 | return value_as_address (val); | |
582 | } | |
583 | ||
584 | case FIELD_LOC_KIND_PHYSNAME: | |
585 | { | |
586 | const char *physname; | |
3b7344d5 | 587 | struct bound_minimal_symbol msym; |
8e3b41a9 JK |
588 | |
589 | physname = FIELD_STATIC_PHYSNAME (call_site->target); | |
9112db09 JK |
590 | |
591 | /* Handle both the mangled and demangled PHYSNAME. */ | |
592 | msym = lookup_minimal_symbol (physname, NULL, NULL); | |
3b7344d5 | 593 | if (msym.minsym == NULL) |
8e3b41a9 | 594 | { |
3b7344d5 | 595 | msym = lookup_minimal_symbol_by_pc (call_site->pc - 1); |
8e3b41a9 JK |
596 | throw_error (NO_ENTRY_VALUE_ERROR, |
597 | _("Cannot find function \"%s\" for a call site target " | |
598 | "at %s in %s"), | |
599 | physname, paddress (call_site_gdbarch, call_site->pc), | |
3b7344d5 TT |
600 | (msym.minsym == NULL ? "???" |
601 | : MSYMBOL_PRINT_NAME (msym.minsym))); | |
8e3b41a9 JK |
602 | |
603 | } | |
77e371c0 | 604 | return BMSYMBOL_VALUE_ADDRESS (msym); |
8e3b41a9 JK |
605 | } |
606 | ||
607 | case FIELD_LOC_KIND_PHYSADDR: | |
608 | return FIELD_STATIC_PHYSADDR (call_site->target); | |
609 | ||
610 | default: | |
611 | internal_error (__FILE__, __LINE__, _("invalid call site target kind")); | |
612 | } | |
613 | } | |
614 | ||
111c6489 JK |
615 | /* Convert function entry point exact address ADDR to the function which is |
616 | compliant with TAIL_CALL_LIST_COMPLETE condition. Throw | |
617 | NO_ENTRY_VALUE_ERROR otherwise. */ | |
618 | ||
619 | static struct symbol * | |
620 | func_addr_to_tail_call_list (struct gdbarch *gdbarch, CORE_ADDR addr) | |
621 | { | |
622 | struct symbol *sym = find_pc_function (addr); | |
623 | struct type *type; | |
624 | ||
625 | if (sym == NULL || BLOCK_START (SYMBOL_BLOCK_VALUE (sym)) != addr) | |
626 | throw_error (NO_ENTRY_VALUE_ERROR, | |
627 | _("DW_TAG_GNU_call_site resolving failed to find function " | |
628 | "name for address %s"), | |
629 | paddress (gdbarch, addr)); | |
630 | ||
631 | type = SYMBOL_TYPE (sym); | |
632 | gdb_assert (TYPE_CODE (type) == TYPE_CODE_FUNC); | |
633 | gdb_assert (TYPE_SPECIFIC_FIELD (type) == TYPE_SPECIFIC_FUNC); | |
634 | ||
635 | return sym; | |
636 | } | |
637 | ||
2d6c5dc2 JK |
638 | /* Verify function with entry point exact address ADDR can never call itself |
639 | via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it | |
640 | can call itself via tail calls. | |
641 | ||
642 | If a funtion can tail call itself its entry value based parameters are | |
643 | unreliable. There is no verification whether the value of some/all | |
644 | parameters is unchanged through the self tail call, we expect if there is | |
645 | a self tail call all the parameters can be modified. */ | |
646 | ||
647 | static void | |
648 | func_verify_no_selftailcall (struct gdbarch *gdbarch, CORE_ADDR verify_addr) | |
649 | { | |
650 | struct obstack addr_obstack; | |
651 | struct cleanup *old_chain; | |
652 | CORE_ADDR addr; | |
653 | ||
654 | /* Track here CORE_ADDRs which were already visited. */ | |
655 | htab_t addr_hash; | |
656 | ||
657 | /* The verification is completely unordered. Track here function addresses | |
658 | which still need to be iterated. */ | |
659 | VEC (CORE_ADDR) *todo = NULL; | |
660 | ||
661 | obstack_init (&addr_obstack); | |
662 | old_chain = make_cleanup_obstack_free (&addr_obstack); | |
663 | addr_hash = htab_create_alloc_ex (64, core_addr_hash, core_addr_eq, NULL, | |
664 | &addr_obstack, hashtab_obstack_allocate, | |
665 | NULL); | |
666 | make_cleanup_htab_delete (addr_hash); | |
667 | ||
668 | make_cleanup (VEC_cleanup (CORE_ADDR), &todo); | |
669 | ||
670 | VEC_safe_push (CORE_ADDR, todo, verify_addr); | |
671 | while (!VEC_empty (CORE_ADDR, todo)) | |
672 | { | |
673 | struct symbol *func_sym; | |
674 | struct call_site *call_site; | |
675 | ||
676 | addr = VEC_pop (CORE_ADDR, todo); | |
677 | ||
678 | func_sym = func_addr_to_tail_call_list (gdbarch, addr); | |
679 | ||
680 | for (call_site = TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym)); | |
681 | call_site; call_site = call_site->tail_call_next) | |
682 | { | |
683 | CORE_ADDR target_addr; | |
684 | void **slot; | |
685 | ||
686 | /* CALLER_FRAME with registers is not available for tail-call jumped | |
687 | frames. */ | |
688 | target_addr = call_site_to_target_addr (gdbarch, call_site, NULL); | |
689 | ||
690 | if (target_addr == verify_addr) | |
691 | { | |
7cbd4a93 | 692 | struct bound_minimal_symbol msym; |
2d6c5dc2 JK |
693 | |
694 | msym = lookup_minimal_symbol_by_pc (verify_addr); | |
695 | throw_error (NO_ENTRY_VALUE_ERROR, | |
696 | _("DW_OP_GNU_entry_value resolving has found " | |
697 | "function \"%s\" at %s can call itself via tail " | |
698 | "calls"), | |
7cbd4a93 | 699 | (msym.minsym == NULL ? "???" |
efd66ac6 | 700 | : MSYMBOL_PRINT_NAME (msym.minsym)), |
2d6c5dc2 JK |
701 | paddress (gdbarch, verify_addr)); |
702 | } | |
703 | ||
704 | slot = htab_find_slot (addr_hash, &target_addr, INSERT); | |
705 | if (*slot == NULL) | |
706 | { | |
707 | *slot = obstack_copy (&addr_obstack, &target_addr, | |
708 | sizeof (target_addr)); | |
709 | VEC_safe_push (CORE_ADDR, todo, target_addr); | |
710 | } | |
711 | } | |
712 | } | |
713 | ||
714 | do_cleanups (old_chain); | |
715 | } | |
716 | ||
111c6489 JK |
717 | /* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for |
718 | ENTRY_VALUES_DEBUG. */ | |
719 | ||
720 | static void | |
721 | tailcall_dump (struct gdbarch *gdbarch, const struct call_site *call_site) | |
722 | { | |
723 | CORE_ADDR addr = call_site->pc; | |
7cbd4a93 | 724 | struct bound_minimal_symbol msym = lookup_minimal_symbol_by_pc (addr - 1); |
111c6489 JK |
725 | |
726 | fprintf_unfiltered (gdb_stdlog, " %s(%s)", paddress (gdbarch, addr), | |
7cbd4a93 | 727 | (msym.minsym == NULL ? "???" |
efd66ac6 | 728 | : MSYMBOL_PRINT_NAME (msym.minsym))); |
111c6489 JK |
729 | |
730 | } | |
731 | ||
732 | /* vec.h needs single word type name, typedef it. */ | |
733 | typedef struct call_site *call_sitep; | |
734 | ||
735 | /* Define VEC (call_sitep) functions. */ | |
736 | DEF_VEC_P (call_sitep); | |
737 | ||
738 | /* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP | |
739 | only top callers and bottom callees which are present in both. GDBARCH is | |
740 | used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are | |
741 | no remaining possibilities to provide unambiguous non-trivial result. | |
742 | RESULTP should point to NULL on the first (initialization) call. Caller is | |
743 | responsible for xfree of any RESULTP data. */ | |
744 | ||
745 | static void | |
746 | chain_candidate (struct gdbarch *gdbarch, struct call_site_chain **resultp, | |
747 | VEC (call_sitep) *chain) | |
748 | { | |
749 | struct call_site_chain *result = *resultp; | |
750 | long length = VEC_length (call_sitep, chain); | |
751 | int callers, callees, idx; | |
752 | ||
753 | if (result == NULL) | |
754 | { | |
755 | /* Create the initial chain containing all the passed PCs. */ | |
756 | ||
757 | result = xmalloc (sizeof (*result) + sizeof (*result->call_site) | |
758 | * (length - 1)); | |
759 | result->length = length; | |
760 | result->callers = result->callees = length; | |
19a1b230 AA |
761 | if (!VEC_empty (call_sitep, chain)) |
762 | memcpy (result->call_site, VEC_address (call_sitep, chain), | |
763 | sizeof (*result->call_site) * length); | |
111c6489 JK |
764 | *resultp = result; |
765 | ||
766 | if (entry_values_debug) | |
767 | { | |
768 | fprintf_unfiltered (gdb_stdlog, "tailcall: initial:"); | |
769 | for (idx = 0; idx < length; idx++) | |
770 | tailcall_dump (gdbarch, result->call_site[idx]); | |
771 | fputc_unfiltered ('\n', gdb_stdlog); | |
772 | } | |
773 | ||
774 | return; | |
775 | } | |
776 | ||
777 | if (entry_values_debug) | |
778 | { | |
779 | fprintf_unfiltered (gdb_stdlog, "tailcall: compare:"); | |
780 | for (idx = 0; idx < length; idx++) | |
781 | tailcall_dump (gdbarch, VEC_index (call_sitep, chain, idx)); | |
782 | fputc_unfiltered ('\n', gdb_stdlog); | |
783 | } | |
784 | ||
785 | /* Intersect callers. */ | |
786 | ||
787 | callers = min (result->callers, length); | |
788 | for (idx = 0; idx < callers; idx++) | |
789 | if (result->call_site[idx] != VEC_index (call_sitep, chain, idx)) | |
790 | { | |
791 | result->callers = idx; | |
792 | break; | |
793 | } | |
794 | ||
795 | /* Intersect callees. */ | |
796 | ||
797 | callees = min (result->callees, length); | |
798 | for (idx = 0; idx < callees; idx++) | |
799 | if (result->call_site[result->length - 1 - idx] | |
800 | != VEC_index (call_sitep, chain, length - 1 - idx)) | |
801 | { | |
802 | result->callees = idx; | |
803 | break; | |
804 | } | |
805 | ||
806 | if (entry_values_debug) | |
807 | { | |
808 | fprintf_unfiltered (gdb_stdlog, "tailcall: reduced:"); | |
809 | for (idx = 0; idx < result->callers; idx++) | |
810 | tailcall_dump (gdbarch, result->call_site[idx]); | |
811 | fputs_unfiltered (" |", gdb_stdlog); | |
812 | for (idx = 0; idx < result->callees; idx++) | |
813 | tailcall_dump (gdbarch, result->call_site[result->length | |
814 | - result->callees + idx]); | |
815 | fputc_unfiltered ('\n', gdb_stdlog); | |
816 | } | |
817 | ||
818 | if (result->callers == 0 && result->callees == 0) | |
819 | { | |
820 | /* There are no common callers or callees. It could be also a direct | |
821 | call (which has length 0) with ambiguous possibility of an indirect | |
822 | call - CALLERS == CALLEES == 0 is valid during the first allocation | |
823 | but any subsequence processing of such entry means ambiguity. */ | |
824 | xfree (result); | |
825 | *resultp = NULL; | |
826 | return; | |
827 | } | |
828 | ||
829 | /* See call_site_find_chain_1 why there is no way to reach the bottom callee | |
830 | PC again. In such case there must be two different code paths to reach | |
831 | it, therefore some of the former determined intermediate PCs must differ | |
832 | and the unambiguous chain gets shortened. */ | |
833 | gdb_assert (result->callers + result->callees < result->length); | |
834 | } | |
835 | ||
836 | /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the | |
837 | assumed frames between them use GDBARCH. Use depth first search so we can | |
838 | keep single CHAIN of call_site's back to CALLER_PC. Function recursion | |
839 | would have needless GDB stack overhead. Caller is responsible for xfree of | |
840 | the returned result. Any unreliability results in thrown | |
841 | NO_ENTRY_VALUE_ERROR. */ | |
842 | ||
843 | static struct call_site_chain * | |
844 | call_site_find_chain_1 (struct gdbarch *gdbarch, CORE_ADDR caller_pc, | |
845 | CORE_ADDR callee_pc) | |
846 | { | |
c4be5165 | 847 | CORE_ADDR save_callee_pc = callee_pc; |
111c6489 JK |
848 | struct obstack addr_obstack; |
849 | struct cleanup *back_to_retval, *back_to_workdata; | |
850 | struct call_site_chain *retval = NULL; | |
851 | struct call_site *call_site; | |
852 | ||
853 | /* Mark CALL_SITEs so we do not visit the same ones twice. */ | |
854 | htab_t addr_hash; | |
855 | ||
856 | /* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's | |
857 | call_site nor any possible call_site at CALLEE_PC's function is there. | |
858 | Any CALL_SITE in CHAIN will be iterated to its siblings - via | |
859 | TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */ | |
860 | VEC (call_sitep) *chain = NULL; | |
861 | ||
862 | /* We are not interested in the specific PC inside the callee function. */ | |
863 | callee_pc = get_pc_function_start (callee_pc); | |
864 | if (callee_pc == 0) | |
865 | throw_error (NO_ENTRY_VALUE_ERROR, _("Unable to find function for PC %s"), | |
c4be5165 | 866 | paddress (gdbarch, save_callee_pc)); |
111c6489 JK |
867 | |
868 | back_to_retval = make_cleanup (free_current_contents, &retval); | |
869 | ||
870 | obstack_init (&addr_obstack); | |
871 | back_to_workdata = make_cleanup_obstack_free (&addr_obstack); | |
872 | addr_hash = htab_create_alloc_ex (64, core_addr_hash, core_addr_eq, NULL, | |
873 | &addr_obstack, hashtab_obstack_allocate, | |
874 | NULL); | |
875 | make_cleanup_htab_delete (addr_hash); | |
876 | ||
877 | make_cleanup (VEC_cleanup (call_sitep), &chain); | |
878 | ||
879 | /* Do not push CALL_SITE to CHAIN. Push there only the first tail call site | |
880 | at the target's function. All the possible tail call sites in the | |
881 | target's function will get iterated as already pushed into CHAIN via their | |
882 | TAIL_CALL_NEXT. */ | |
883 | call_site = call_site_for_pc (gdbarch, caller_pc); | |
884 | ||
885 | while (call_site) | |
886 | { | |
887 | CORE_ADDR target_func_addr; | |
888 | struct call_site *target_call_site; | |
889 | ||
890 | /* CALLER_FRAME with registers is not available for tail-call jumped | |
891 | frames. */ | |
892 | target_func_addr = call_site_to_target_addr (gdbarch, call_site, NULL); | |
893 | ||
894 | if (target_func_addr == callee_pc) | |
895 | { | |
896 | chain_candidate (gdbarch, &retval, chain); | |
897 | if (retval == NULL) | |
898 | break; | |
899 | ||
900 | /* There is no way to reach CALLEE_PC again as we would prevent | |
901 | entering it twice as being already marked in ADDR_HASH. */ | |
902 | target_call_site = NULL; | |
903 | } | |
904 | else | |
905 | { | |
906 | struct symbol *target_func; | |
907 | ||
908 | target_func = func_addr_to_tail_call_list (gdbarch, target_func_addr); | |
909 | target_call_site = TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func)); | |
910 | } | |
911 | ||
912 | do | |
913 | { | |
914 | /* Attempt to visit TARGET_CALL_SITE. */ | |
915 | ||
916 | if (target_call_site) | |
917 | { | |
918 | void **slot; | |
919 | ||
920 | slot = htab_find_slot (addr_hash, &target_call_site->pc, INSERT); | |
921 | if (*slot == NULL) | |
922 | { | |
923 | /* Successfully entered TARGET_CALL_SITE. */ | |
924 | ||
925 | *slot = &target_call_site->pc; | |
926 | VEC_safe_push (call_sitep, chain, target_call_site); | |
927 | break; | |
928 | } | |
929 | } | |
930 | ||
931 | /* Backtrack (without revisiting the originating call_site). Try the | |
932 | callers's sibling; if there isn't any try the callers's callers's | |
933 | sibling etc. */ | |
934 | ||
935 | target_call_site = NULL; | |
936 | while (!VEC_empty (call_sitep, chain)) | |
937 | { | |
938 | call_site = VEC_pop (call_sitep, chain); | |
939 | ||
940 | gdb_assert (htab_find_slot (addr_hash, &call_site->pc, | |
941 | NO_INSERT) != NULL); | |
942 | htab_remove_elt (addr_hash, &call_site->pc); | |
943 | ||
944 | target_call_site = call_site->tail_call_next; | |
945 | if (target_call_site) | |
946 | break; | |
947 | } | |
948 | } | |
949 | while (target_call_site); | |
950 | ||
951 | if (VEC_empty (call_sitep, chain)) | |
952 | call_site = NULL; | |
953 | else | |
954 | call_site = VEC_last (call_sitep, chain); | |
955 | } | |
956 | ||
957 | if (retval == NULL) | |
958 | { | |
7cbd4a93 | 959 | struct bound_minimal_symbol msym_caller, msym_callee; |
111c6489 JK |
960 | |
961 | msym_caller = lookup_minimal_symbol_by_pc (caller_pc); | |
962 | msym_callee = lookup_minimal_symbol_by_pc (callee_pc); | |
963 | throw_error (NO_ENTRY_VALUE_ERROR, | |
964 | _("There are no unambiguously determinable intermediate " | |
965 | "callers or callees between caller function \"%s\" at %s " | |
966 | "and callee function \"%s\" at %s"), | |
7cbd4a93 | 967 | (msym_caller.minsym == NULL |
efd66ac6 | 968 | ? "???" : MSYMBOL_PRINT_NAME (msym_caller.minsym)), |
111c6489 | 969 | paddress (gdbarch, caller_pc), |
7cbd4a93 | 970 | (msym_callee.minsym == NULL |
efd66ac6 | 971 | ? "???" : MSYMBOL_PRINT_NAME (msym_callee.minsym)), |
111c6489 JK |
972 | paddress (gdbarch, callee_pc)); |
973 | } | |
974 | ||
975 | do_cleanups (back_to_workdata); | |
976 | discard_cleanups (back_to_retval); | |
977 | return retval; | |
978 | } | |
979 | ||
980 | /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the | |
981 | assumed frames between them use GDBARCH. If valid call_site_chain cannot be | |
982 | constructed return NULL. Caller is responsible for xfree of the returned | |
983 | result. */ | |
984 | ||
985 | struct call_site_chain * | |
986 | call_site_find_chain (struct gdbarch *gdbarch, CORE_ADDR caller_pc, | |
987 | CORE_ADDR callee_pc) | |
988 | { | |
989 | volatile struct gdb_exception e; | |
990 | struct call_site_chain *retval = NULL; | |
991 | ||
992 | TRY_CATCH (e, RETURN_MASK_ERROR) | |
993 | { | |
994 | retval = call_site_find_chain_1 (gdbarch, caller_pc, callee_pc); | |
995 | } | |
996 | if (e.reason < 0) | |
997 | { | |
998 | if (e.error == NO_ENTRY_VALUE_ERROR) | |
999 | { | |
1000 | if (entry_values_debug) | |
1001 | exception_print (gdb_stdout, e); | |
1002 | ||
1003 | return NULL; | |
1004 | } | |
1005 | else | |
1006 | throw_exception (e); | |
1007 | } | |
1008 | return retval; | |
1009 | } | |
1010 | ||
24c5c679 JK |
1011 | /* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */ |
1012 | ||
1013 | static int | |
1014 | call_site_parameter_matches (struct call_site_parameter *parameter, | |
1015 | enum call_site_parameter_kind kind, | |
1016 | union call_site_parameter_u kind_u) | |
1017 | { | |
1018 | if (kind == parameter->kind) | |
1019 | switch (kind) | |
1020 | { | |
1021 | case CALL_SITE_PARAMETER_DWARF_REG: | |
1022 | return kind_u.dwarf_reg == parameter->u.dwarf_reg; | |
1023 | case CALL_SITE_PARAMETER_FB_OFFSET: | |
1024 | return kind_u.fb_offset == parameter->u.fb_offset; | |
1788b2d3 JK |
1025 | case CALL_SITE_PARAMETER_PARAM_OFFSET: |
1026 | return kind_u.param_offset.cu_off == parameter->u.param_offset.cu_off; | |
24c5c679 JK |
1027 | } |
1028 | return 0; | |
1029 | } | |
1030 | ||
1031 | /* Fetch call_site_parameter from caller matching KIND and KIND_U. | |
1032 | FRAME is for callee. | |
8e3b41a9 JK |
1033 | |
1034 | Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR | |
1035 | otherwise. */ | |
1036 | ||
1037 | static struct call_site_parameter * | |
24c5c679 JK |
1038 | dwarf_expr_reg_to_entry_parameter (struct frame_info *frame, |
1039 | enum call_site_parameter_kind kind, | |
1040 | union call_site_parameter_u kind_u, | |
8e3b41a9 JK |
1041 | struct dwarf2_per_cu_data **per_cu_return) |
1042 | { | |
9e3a7d65 JK |
1043 | CORE_ADDR func_addr, caller_pc; |
1044 | struct gdbarch *gdbarch; | |
1045 | struct frame_info *caller_frame; | |
8e3b41a9 JK |
1046 | struct call_site *call_site; |
1047 | int iparams; | |
509f0fd9 JK |
1048 | /* Initialize it just to avoid a GCC false warning. */ |
1049 | struct call_site_parameter *parameter = NULL; | |
8e3b41a9 JK |
1050 | CORE_ADDR target_addr; |
1051 | ||
9e3a7d65 JK |
1052 | while (get_frame_type (frame) == INLINE_FRAME) |
1053 | { | |
1054 | frame = get_prev_frame (frame); | |
1055 | gdb_assert (frame != NULL); | |
1056 | } | |
1057 | ||
1058 | func_addr = get_frame_func (frame); | |
1059 | gdbarch = get_frame_arch (frame); | |
1060 | caller_frame = get_prev_frame (frame); | |
8e3b41a9 JK |
1061 | if (gdbarch != frame_unwind_arch (frame)) |
1062 | { | |
7cbd4a93 TT |
1063 | struct bound_minimal_symbol msym |
1064 | = lookup_minimal_symbol_by_pc (func_addr); | |
8e3b41a9 JK |
1065 | struct gdbarch *caller_gdbarch = frame_unwind_arch (frame); |
1066 | ||
1067 | throw_error (NO_ENTRY_VALUE_ERROR, | |
1068 | _("DW_OP_GNU_entry_value resolving callee gdbarch %s " | |
1069 | "(of %s (%s)) does not match caller gdbarch %s"), | |
1070 | gdbarch_bfd_arch_info (gdbarch)->printable_name, | |
1071 | paddress (gdbarch, func_addr), | |
7cbd4a93 | 1072 | (msym.minsym == NULL ? "???" |
efd66ac6 | 1073 | : MSYMBOL_PRINT_NAME (msym.minsym)), |
8e3b41a9 JK |
1074 | gdbarch_bfd_arch_info (caller_gdbarch)->printable_name); |
1075 | } | |
1076 | ||
1077 | if (caller_frame == NULL) | |
1078 | { | |
7cbd4a93 TT |
1079 | struct bound_minimal_symbol msym |
1080 | = lookup_minimal_symbol_by_pc (func_addr); | |
8e3b41a9 JK |
1081 | |
1082 | throw_error (NO_ENTRY_VALUE_ERROR, _("DW_OP_GNU_entry_value resolving " | |
1083 | "requires caller of %s (%s)"), | |
1084 | paddress (gdbarch, func_addr), | |
7cbd4a93 | 1085 | (msym.minsym == NULL ? "???" |
efd66ac6 | 1086 | : MSYMBOL_PRINT_NAME (msym.minsym))); |
8e3b41a9 JK |
1087 | } |
1088 | caller_pc = get_frame_pc (caller_frame); | |
1089 | call_site = call_site_for_pc (gdbarch, caller_pc); | |
1090 | ||
1091 | target_addr = call_site_to_target_addr (gdbarch, call_site, caller_frame); | |
1092 | if (target_addr != func_addr) | |
1093 | { | |
1094 | struct minimal_symbol *target_msym, *func_msym; | |
1095 | ||
7cbd4a93 TT |
1096 | target_msym = lookup_minimal_symbol_by_pc (target_addr).minsym; |
1097 | func_msym = lookup_minimal_symbol_by_pc (func_addr).minsym; | |
8e3b41a9 JK |
1098 | throw_error (NO_ENTRY_VALUE_ERROR, |
1099 | _("DW_OP_GNU_entry_value resolving expects callee %s at %s " | |
1100 | "but the called frame is for %s at %s"), | |
1101 | (target_msym == NULL ? "???" | |
efd66ac6 | 1102 | : MSYMBOL_PRINT_NAME (target_msym)), |
8e3b41a9 | 1103 | paddress (gdbarch, target_addr), |
efd66ac6 | 1104 | func_msym == NULL ? "???" : MSYMBOL_PRINT_NAME (func_msym), |
8e3b41a9 JK |
1105 | paddress (gdbarch, func_addr)); |
1106 | } | |
1107 | ||
2d6c5dc2 JK |
1108 | /* No entry value based parameters would be reliable if this function can |
1109 | call itself via tail calls. */ | |
1110 | func_verify_no_selftailcall (gdbarch, func_addr); | |
1111 | ||
8e3b41a9 JK |
1112 | for (iparams = 0; iparams < call_site->parameter_count; iparams++) |
1113 | { | |
1114 | parameter = &call_site->parameter[iparams]; | |
24c5c679 | 1115 | if (call_site_parameter_matches (parameter, kind, kind_u)) |
8e3b41a9 JK |
1116 | break; |
1117 | } | |
1118 | if (iparams == call_site->parameter_count) | |
1119 | { | |
7cbd4a93 TT |
1120 | struct minimal_symbol *msym |
1121 | = lookup_minimal_symbol_by_pc (caller_pc).minsym; | |
8e3b41a9 JK |
1122 | |
1123 | /* DW_TAG_GNU_call_site_parameter will be missing just if GCC could not | |
1124 | determine its value. */ | |
1125 | throw_error (NO_ENTRY_VALUE_ERROR, _("Cannot find matching parameter " | |
1126 | "at DW_TAG_GNU_call_site %s at %s"), | |
1127 | paddress (gdbarch, caller_pc), | |
efd66ac6 | 1128 | msym == NULL ? "???" : MSYMBOL_PRINT_NAME (msym)); |
8e3b41a9 JK |
1129 | } |
1130 | ||
1131 | *per_cu_return = call_site->per_cu; | |
1132 | return parameter; | |
1133 | } | |
1134 | ||
a471c594 JK |
1135 | /* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return |
1136 | the normal DW_AT_GNU_call_site_value block. Otherwise return the | |
1137 | DW_AT_GNU_call_site_data_value (dereferenced) block. | |
e18b2753 JK |
1138 | |
1139 | TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned | |
1140 | struct value. | |
1141 | ||
1142 | Function always returns non-NULL, non-optimized out value. It throws | |
1143 | NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */ | |
1144 | ||
1145 | static struct value * | |
1146 | dwarf_entry_parameter_to_value (struct call_site_parameter *parameter, | |
a471c594 | 1147 | CORE_ADDR deref_size, struct type *type, |
e18b2753 JK |
1148 | struct frame_info *caller_frame, |
1149 | struct dwarf2_per_cu_data *per_cu) | |
1150 | { | |
a471c594 | 1151 | const gdb_byte *data_src; |
e18b2753 | 1152 | gdb_byte *data; |
a471c594 JK |
1153 | size_t size; |
1154 | ||
1155 | data_src = deref_size == -1 ? parameter->value : parameter->data_value; | |
1156 | size = deref_size == -1 ? parameter->value_size : parameter->data_value_size; | |
1157 | ||
1158 | /* DEREF_SIZE size is not verified here. */ | |
1159 | if (data_src == NULL) | |
1160 | throw_error (NO_ENTRY_VALUE_ERROR, | |
1161 | _("Cannot resolve DW_AT_GNU_call_site_data_value")); | |
e18b2753 JK |
1162 | |
1163 | /* DW_AT_GNU_call_site_value is a DWARF expression, not a DWARF | |
1164 | location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from | |
1165 | DWARF block. */ | |
a471c594 JK |
1166 | data = alloca (size + 1); |
1167 | memcpy (data, data_src, size); | |
1168 | data[size] = DW_OP_stack_value; | |
e18b2753 | 1169 | |
a471c594 | 1170 | return dwarf2_evaluate_loc_desc (type, caller_frame, data, size + 1, per_cu); |
e18b2753 JK |
1171 | } |
1172 | ||
24c5c679 JK |
1173 | /* Execute DWARF block of call_site_parameter which matches KIND and KIND_U. |
1174 | Choose DEREF_SIZE value of that parameter. Search caller of the CTX's | |
1175 | frame. CTX must be of dwarf_expr_ctx_funcs kind. | |
8e3b41a9 JK |
1176 | |
1177 | The CTX caller can be from a different CU - per_cu_dwarf_call implementation | |
1178 | can be more simple as it does not support cross-CU DWARF executions. */ | |
1179 | ||
1180 | static void | |
1181 | dwarf_expr_push_dwarf_reg_entry_value (struct dwarf_expr_context *ctx, | |
24c5c679 JK |
1182 | enum call_site_parameter_kind kind, |
1183 | union call_site_parameter_u kind_u, | |
a471c594 | 1184 | int deref_size) |
8e3b41a9 JK |
1185 | { |
1186 | struct dwarf_expr_baton *debaton; | |
1187 | struct frame_info *frame, *caller_frame; | |
1188 | struct dwarf2_per_cu_data *caller_per_cu; | |
1189 | struct dwarf_expr_baton baton_local; | |
1190 | struct dwarf_expr_context saved_ctx; | |
1191 | struct call_site_parameter *parameter; | |
1192 | const gdb_byte *data_src; | |
1193 | size_t size; | |
1194 | ||
1195 | gdb_assert (ctx->funcs == &dwarf_expr_ctx_funcs); | |
1196 | debaton = ctx->baton; | |
1197 | frame = debaton->frame; | |
1198 | caller_frame = get_prev_frame (frame); | |
1199 | ||
24c5c679 | 1200 | parameter = dwarf_expr_reg_to_entry_parameter (frame, kind, kind_u, |
8e3b41a9 | 1201 | &caller_per_cu); |
a471c594 JK |
1202 | data_src = deref_size == -1 ? parameter->value : parameter->data_value; |
1203 | size = deref_size == -1 ? parameter->value_size : parameter->data_value_size; | |
1204 | ||
1205 | /* DEREF_SIZE size is not verified here. */ | |
1206 | if (data_src == NULL) | |
1207 | throw_error (NO_ENTRY_VALUE_ERROR, | |
1208 | _("Cannot resolve DW_AT_GNU_call_site_data_value")); | |
8e3b41a9 JK |
1209 | |
1210 | baton_local.frame = caller_frame; | |
1211 | baton_local.per_cu = caller_per_cu; | |
1212 | ||
1213 | saved_ctx.gdbarch = ctx->gdbarch; | |
1214 | saved_ctx.addr_size = ctx->addr_size; | |
1215 | saved_ctx.offset = ctx->offset; | |
1216 | saved_ctx.baton = ctx->baton; | |
1217 | ctx->gdbarch = get_objfile_arch (dwarf2_per_cu_objfile (baton_local.per_cu)); | |
1218 | ctx->addr_size = dwarf2_per_cu_addr_size (baton_local.per_cu); | |
1219 | ctx->offset = dwarf2_per_cu_text_offset (baton_local.per_cu); | |
1220 | ctx->baton = &baton_local; | |
1221 | ||
1222 | dwarf_expr_eval (ctx, data_src, size); | |
1223 | ||
1224 | ctx->gdbarch = saved_ctx.gdbarch; | |
1225 | ctx->addr_size = saved_ctx.addr_size; | |
1226 | ctx->offset = saved_ctx.offset; | |
1227 | ctx->baton = saved_ctx.baton; | |
1228 | } | |
1229 | ||
3019eac3 DE |
1230 | /* Callback function for dwarf2_evaluate_loc_desc. |
1231 | Fetch the address indexed by DW_OP_GNU_addr_index. */ | |
1232 | ||
1233 | static CORE_ADDR | |
1234 | dwarf_expr_get_addr_index (void *baton, unsigned int index) | |
1235 | { | |
1236 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
1237 | ||
1238 | return dwarf2_read_addr_index (debaton->per_cu, index); | |
1239 | } | |
1240 | ||
a471c594 JK |
1241 | /* VALUE must be of type lval_computed with entry_data_value_funcs. Perform |
1242 | the indirect method on it, that is use its stored target value, the sole | |
1243 | purpose of entry_data_value_funcs.. */ | |
1244 | ||
1245 | static struct value * | |
1246 | entry_data_value_coerce_ref (const struct value *value) | |
1247 | { | |
1248 | struct type *checked_type = check_typedef (value_type (value)); | |
1249 | struct value *target_val; | |
1250 | ||
1251 | if (TYPE_CODE (checked_type) != TYPE_CODE_REF) | |
1252 | return NULL; | |
1253 | ||
1254 | target_val = value_computed_closure (value); | |
1255 | value_incref (target_val); | |
1256 | return target_val; | |
1257 | } | |
1258 | ||
1259 | /* Implement copy_closure. */ | |
1260 | ||
1261 | static void * | |
1262 | entry_data_value_copy_closure (const struct value *v) | |
1263 | { | |
1264 | struct value *target_val = value_computed_closure (v); | |
1265 | ||
1266 | value_incref (target_val); | |
1267 | return target_val; | |
1268 | } | |
1269 | ||
1270 | /* Implement free_closure. */ | |
1271 | ||
1272 | static void | |
1273 | entry_data_value_free_closure (struct value *v) | |
1274 | { | |
1275 | struct value *target_val = value_computed_closure (v); | |
1276 | ||
1277 | value_free (target_val); | |
1278 | } | |
1279 | ||
1280 | /* Vector for methods for an entry value reference where the referenced value | |
1281 | is stored in the caller. On the first dereference use | |
1282 | DW_AT_GNU_call_site_data_value in the caller. */ | |
1283 | ||
1284 | static const struct lval_funcs entry_data_value_funcs = | |
1285 | { | |
1286 | NULL, /* read */ | |
1287 | NULL, /* write */ | |
1288 | NULL, /* check_validity */ | |
1289 | NULL, /* check_any_valid */ | |
1290 | NULL, /* indirect */ | |
1291 | entry_data_value_coerce_ref, | |
1292 | NULL, /* check_synthetic_pointer */ | |
1293 | entry_data_value_copy_closure, | |
1294 | entry_data_value_free_closure | |
1295 | }; | |
1296 | ||
24c5c679 JK |
1297 | /* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U |
1298 | are used to match DW_AT_location at the caller's | |
1299 | DW_TAG_GNU_call_site_parameter. | |
e18b2753 JK |
1300 | |
1301 | Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it | |
1302 | cannot resolve the parameter for any reason. */ | |
1303 | ||
1304 | static struct value * | |
1305 | value_of_dwarf_reg_entry (struct type *type, struct frame_info *frame, | |
24c5c679 JK |
1306 | enum call_site_parameter_kind kind, |
1307 | union call_site_parameter_u kind_u) | |
e18b2753 | 1308 | { |
a471c594 JK |
1309 | struct type *checked_type = check_typedef (type); |
1310 | struct type *target_type = TYPE_TARGET_TYPE (checked_type); | |
e18b2753 | 1311 | struct frame_info *caller_frame = get_prev_frame (frame); |
a471c594 | 1312 | struct value *outer_val, *target_val, *val; |
e18b2753 JK |
1313 | struct call_site_parameter *parameter; |
1314 | struct dwarf2_per_cu_data *caller_per_cu; | |
a471c594 | 1315 | CORE_ADDR addr; |
e18b2753 | 1316 | |
24c5c679 | 1317 | parameter = dwarf_expr_reg_to_entry_parameter (frame, kind, kind_u, |
e18b2753 JK |
1318 | &caller_per_cu); |
1319 | ||
a471c594 JK |
1320 | outer_val = dwarf_entry_parameter_to_value (parameter, -1 /* deref_size */, |
1321 | type, caller_frame, | |
1322 | caller_per_cu); | |
1323 | ||
1324 | /* Check if DW_AT_GNU_call_site_data_value cannot be used. If it should be | |
1325 | used and it is not available do not fall back to OUTER_VAL - dereferencing | |
1326 | TYPE_CODE_REF with non-entry data value would give current value - not the | |
1327 | entry value. */ | |
1328 | ||
1329 | if (TYPE_CODE (checked_type) != TYPE_CODE_REF | |
1330 | || TYPE_TARGET_TYPE (checked_type) == NULL) | |
1331 | return outer_val; | |
1332 | ||
1333 | target_val = dwarf_entry_parameter_to_value (parameter, | |
1334 | TYPE_LENGTH (target_type), | |
1335 | target_type, caller_frame, | |
1336 | caller_per_cu); | |
1337 | ||
1338 | /* value_as_address dereferences TYPE_CODE_REF. */ | |
1339 | addr = extract_typed_address (value_contents (outer_val), checked_type); | |
1340 | ||
1341 | /* The target entry value has artificial address of the entry value | |
1342 | reference. */ | |
1343 | VALUE_LVAL (target_val) = lval_memory; | |
1344 | set_value_address (target_val, addr); | |
1345 | ||
1346 | release_value (target_val); | |
1347 | val = allocate_computed_value (type, &entry_data_value_funcs, | |
1348 | target_val /* closure */); | |
1349 | ||
1350 | /* Copy the referencing pointer to the new computed value. */ | |
1351 | memcpy (value_contents_raw (val), value_contents_raw (outer_val), | |
1352 | TYPE_LENGTH (checked_type)); | |
1353 | set_value_lazy (val, 0); | |
1354 | ||
1355 | return val; | |
e18b2753 JK |
1356 | } |
1357 | ||
1358 | /* Read parameter of TYPE at (callee) FRAME's function entry. DATA and | |
1359 | SIZE are DWARF block used to match DW_AT_location at the caller's | |
1360 | DW_TAG_GNU_call_site_parameter. | |
1361 | ||
1362 | Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it | |
1363 | cannot resolve the parameter for any reason. */ | |
1364 | ||
1365 | static struct value * | |
1366 | value_of_dwarf_block_entry (struct type *type, struct frame_info *frame, | |
1367 | const gdb_byte *block, size_t block_len) | |
1368 | { | |
24c5c679 | 1369 | union call_site_parameter_u kind_u; |
e18b2753 | 1370 | |
24c5c679 JK |
1371 | kind_u.dwarf_reg = dwarf_block_to_dwarf_reg (block, block + block_len); |
1372 | if (kind_u.dwarf_reg != -1) | |
1373 | return value_of_dwarf_reg_entry (type, frame, CALL_SITE_PARAMETER_DWARF_REG, | |
1374 | kind_u); | |
e18b2753 | 1375 | |
24c5c679 JK |
1376 | if (dwarf_block_to_fb_offset (block, block + block_len, &kind_u.fb_offset)) |
1377 | return value_of_dwarf_reg_entry (type, frame, CALL_SITE_PARAMETER_FB_OFFSET, | |
1378 | kind_u); | |
e18b2753 JK |
1379 | |
1380 | /* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message | |
1381 | suppressed during normal operation. The expression can be arbitrary if | |
1382 | there is no caller-callee entry value binding expected. */ | |
1383 | throw_error (NO_ENTRY_VALUE_ERROR, | |
1384 | _("DWARF-2 expression error: DW_OP_GNU_entry_value is supported " | |
1385 | "only for single DW_OP_reg* or for DW_OP_fbreg(*)")); | |
1386 | } | |
1387 | ||
052b9502 NF |
1388 | struct piece_closure |
1389 | { | |
88bfdde4 TT |
1390 | /* Reference count. */ |
1391 | int refc; | |
1392 | ||
8cf6f0b1 TT |
1393 | /* The CU from which this closure's expression came. */ |
1394 | struct dwarf2_per_cu_data *per_cu; | |
1395 | ||
052b9502 NF |
1396 | /* The number of pieces used to describe this variable. */ |
1397 | int n_pieces; | |
1398 | ||
6063c216 UW |
1399 | /* The target address size, used only for DWARF_VALUE_STACK. */ |
1400 | int addr_size; | |
cec03d70 | 1401 | |
052b9502 NF |
1402 | /* The pieces themselves. */ |
1403 | struct dwarf_expr_piece *pieces; | |
1404 | }; | |
1405 | ||
1406 | /* Allocate a closure for a value formed from separately-described | |
1407 | PIECES. */ | |
1408 | ||
1409 | static struct piece_closure * | |
8cf6f0b1 TT |
1410 | allocate_piece_closure (struct dwarf2_per_cu_data *per_cu, |
1411 | int n_pieces, struct dwarf_expr_piece *pieces, | |
6063c216 | 1412 | int addr_size) |
052b9502 | 1413 | { |
41bf6aca | 1414 | struct piece_closure *c = XCNEW (struct piece_closure); |
8a9b8146 | 1415 | int i; |
052b9502 | 1416 | |
88bfdde4 | 1417 | c->refc = 1; |
8cf6f0b1 | 1418 | c->per_cu = per_cu; |
052b9502 | 1419 | c->n_pieces = n_pieces; |
6063c216 | 1420 | c->addr_size = addr_size; |
fc270c35 | 1421 | c->pieces = XCNEWVEC (struct dwarf_expr_piece, n_pieces); |
052b9502 NF |
1422 | |
1423 | memcpy (c->pieces, pieces, n_pieces * sizeof (struct dwarf_expr_piece)); | |
8a9b8146 TT |
1424 | for (i = 0; i < n_pieces; ++i) |
1425 | if (c->pieces[i].location == DWARF_VALUE_STACK) | |
1426 | value_incref (c->pieces[i].v.value); | |
052b9502 NF |
1427 | |
1428 | return c; | |
1429 | } | |
1430 | ||
d3b1e874 TT |
1431 | /* The lowest-level function to extract bits from a byte buffer. |
1432 | SOURCE is the buffer. It is updated if we read to the end of a | |
1433 | byte. | |
1434 | SOURCE_OFFSET_BITS is the offset of the first bit to read. It is | |
1435 | updated to reflect the number of bits actually read. | |
1436 | NBITS is the number of bits we want to read. It is updated to | |
1437 | reflect the number of bits actually read. This function may read | |
1438 | fewer bits. | |
1439 | BITS_BIG_ENDIAN is taken directly from gdbarch. | |
1440 | This function returns the extracted bits. */ | |
1441 | ||
1442 | static unsigned int | |
1443 | extract_bits_primitive (const gdb_byte **source, | |
1444 | unsigned int *source_offset_bits, | |
1445 | int *nbits, int bits_big_endian) | |
1446 | { | |
1447 | unsigned int avail, mask, datum; | |
1448 | ||
1449 | gdb_assert (*source_offset_bits < 8); | |
1450 | ||
1451 | avail = 8 - *source_offset_bits; | |
1452 | if (avail > *nbits) | |
1453 | avail = *nbits; | |
1454 | ||
1455 | mask = (1 << avail) - 1; | |
1456 | datum = **source; | |
1457 | if (bits_big_endian) | |
1458 | datum >>= 8 - (*source_offset_bits + *nbits); | |
1459 | else | |
1460 | datum >>= *source_offset_bits; | |
1461 | datum &= mask; | |
1462 | ||
1463 | *nbits -= avail; | |
1464 | *source_offset_bits += avail; | |
1465 | if (*source_offset_bits >= 8) | |
1466 | { | |
1467 | *source_offset_bits -= 8; | |
1468 | ++*source; | |
1469 | } | |
1470 | ||
1471 | return datum; | |
1472 | } | |
1473 | ||
1474 | /* Extract some bits from a source buffer and move forward in the | |
1475 | buffer. | |
1476 | ||
1477 | SOURCE is the source buffer. It is updated as bytes are read. | |
1478 | SOURCE_OFFSET_BITS is the offset into SOURCE. It is updated as | |
1479 | bits are read. | |
1480 | NBITS is the number of bits to read. | |
1481 | BITS_BIG_ENDIAN is taken directly from gdbarch. | |
1482 | ||
1483 | This function returns the bits that were read. */ | |
1484 | ||
1485 | static unsigned int | |
1486 | extract_bits (const gdb_byte **source, unsigned int *source_offset_bits, | |
1487 | int nbits, int bits_big_endian) | |
1488 | { | |
1489 | unsigned int datum; | |
1490 | ||
1491 | gdb_assert (nbits > 0 && nbits <= 8); | |
1492 | ||
1493 | datum = extract_bits_primitive (source, source_offset_bits, &nbits, | |
1494 | bits_big_endian); | |
1495 | if (nbits > 0) | |
1496 | { | |
1497 | unsigned int more; | |
1498 | ||
1499 | more = extract_bits_primitive (source, source_offset_bits, &nbits, | |
1500 | bits_big_endian); | |
1501 | if (bits_big_endian) | |
1502 | datum <<= nbits; | |
1503 | else | |
1504 | more <<= nbits; | |
1505 | datum |= more; | |
1506 | } | |
1507 | ||
1508 | return datum; | |
1509 | } | |
1510 | ||
1511 | /* Write some bits into a buffer and move forward in the buffer. | |
1512 | ||
1513 | DATUM is the bits to write. The low-order bits of DATUM are used. | |
1514 | DEST is the destination buffer. It is updated as bytes are | |
1515 | written. | |
1516 | DEST_OFFSET_BITS is the bit offset in DEST at which writing is | |
1517 | done. | |
1518 | NBITS is the number of valid bits in DATUM. | |
1519 | BITS_BIG_ENDIAN is taken directly from gdbarch. */ | |
1520 | ||
1521 | static void | |
1522 | insert_bits (unsigned int datum, | |
1523 | gdb_byte *dest, unsigned int dest_offset_bits, | |
1524 | int nbits, int bits_big_endian) | |
1525 | { | |
1526 | unsigned int mask; | |
1527 | ||
8c814cdd | 1528 | gdb_assert (dest_offset_bits + nbits <= 8); |
d3b1e874 TT |
1529 | |
1530 | mask = (1 << nbits) - 1; | |
1531 | if (bits_big_endian) | |
1532 | { | |
1533 | datum <<= 8 - (dest_offset_bits + nbits); | |
1534 | mask <<= 8 - (dest_offset_bits + nbits); | |
1535 | } | |
1536 | else | |
1537 | { | |
1538 | datum <<= dest_offset_bits; | |
1539 | mask <<= dest_offset_bits; | |
1540 | } | |
1541 | ||
1542 | gdb_assert ((datum & ~mask) == 0); | |
1543 | ||
1544 | *dest = (*dest & ~mask) | datum; | |
1545 | } | |
1546 | ||
1547 | /* Copy bits from a source to a destination. | |
1548 | ||
1549 | DEST is where the bits should be written. | |
1550 | DEST_OFFSET_BITS is the bit offset into DEST. | |
1551 | SOURCE is the source of bits. | |
1552 | SOURCE_OFFSET_BITS is the bit offset into SOURCE. | |
1553 | BIT_COUNT is the number of bits to copy. | |
1554 | BITS_BIG_ENDIAN is taken directly from gdbarch. */ | |
1555 | ||
1556 | static void | |
1557 | copy_bitwise (gdb_byte *dest, unsigned int dest_offset_bits, | |
1558 | const gdb_byte *source, unsigned int source_offset_bits, | |
1559 | unsigned int bit_count, | |
1560 | int bits_big_endian) | |
1561 | { | |
1562 | unsigned int dest_avail; | |
1563 | int datum; | |
1564 | ||
1565 | /* Reduce everything to byte-size pieces. */ | |
1566 | dest += dest_offset_bits / 8; | |
1567 | dest_offset_bits %= 8; | |
1568 | source += source_offset_bits / 8; | |
1569 | source_offset_bits %= 8; | |
1570 | ||
1571 | dest_avail = 8 - dest_offset_bits % 8; | |
1572 | ||
1573 | /* See if we can fill the first destination byte. */ | |
1574 | if (dest_avail < bit_count) | |
1575 | { | |
1576 | datum = extract_bits (&source, &source_offset_bits, dest_avail, | |
1577 | bits_big_endian); | |
1578 | insert_bits (datum, dest, dest_offset_bits, dest_avail, bits_big_endian); | |
1579 | ++dest; | |
1580 | dest_offset_bits = 0; | |
1581 | bit_count -= dest_avail; | |
1582 | } | |
1583 | ||
1584 | /* Now, either DEST_OFFSET_BITS is byte-aligned, or we have fewer | |
1585 | than 8 bits remaining. */ | |
1586 | gdb_assert (dest_offset_bits % 8 == 0 || bit_count < 8); | |
1587 | for (; bit_count >= 8; bit_count -= 8) | |
1588 | { | |
1589 | datum = extract_bits (&source, &source_offset_bits, 8, bits_big_endian); | |
1590 | *dest++ = (gdb_byte) datum; | |
1591 | } | |
1592 | ||
1593 | /* Finally, we may have a few leftover bits. */ | |
1594 | gdb_assert (bit_count <= 8 - dest_offset_bits % 8); | |
1595 | if (bit_count > 0) | |
1596 | { | |
1597 | datum = extract_bits (&source, &source_offset_bits, bit_count, | |
1598 | bits_big_endian); | |
1599 | insert_bits (datum, dest, dest_offset_bits, bit_count, bits_big_endian); | |
1600 | } | |
1601 | } | |
1602 | ||
052b9502 NF |
1603 | static void |
1604 | read_pieced_value (struct value *v) | |
1605 | { | |
1606 | int i; | |
1607 | long offset = 0; | |
d3b1e874 | 1608 | ULONGEST bits_to_skip; |
052b9502 | 1609 | gdb_byte *contents; |
3e43a32a MS |
1610 | struct piece_closure *c |
1611 | = (struct piece_closure *) value_computed_closure (v); | |
052b9502 | 1612 | struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (v)); |
afd74c5f | 1613 | size_t type_len; |
d3b1e874 | 1614 | size_t buffer_size = 0; |
948f8e3d | 1615 | gdb_byte *buffer = NULL; |
d3b1e874 TT |
1616 | struct cleanup *cleanup; |
1617 | int bits_big_endian | |
1618 | = gdbarch_bits_big_endian (get_type_arch (value_type (v))); | |
afd74c5f TT |
1619 | |
1620 | if (value_type (v) != value_enclosing_type (v)) | |
1621 | internal_error (__FILE__, __LINE__, | |
1622 | _("Should not be able to create a lazy value with " | |
1623 | "an enclosing type")); | |
052b9502 | 1624 | |
d3b1e874 TT |
1625 | cleanup = make_cleanup (free_current_contents, &buffer); |
1626 | ||
052b9502 | 1627 | contents = value_contents_raw (v); |
d3b1e874 | 1628 | bits_to_skip = 8 * value_offset (v); |
0e03807e TT |
1629 | if (value_bitsize (v)) |
1630 | { | |
1631 | bits_to_skip += value_bitpos (v); | |
1632 | type_len = value_bitsize (v); | |
1633 | } | |
1634 | else | |
1635 | type_len = 8 * TYPE_LENGTH (value_type (v)); | |
d3b1e874 | 1636 | |
afd74c5f | 1637 | for (i = 0; i < c->n_pieces && offset < type_len; i++) |
052b9502 NF |
1638 | { |
1639 | struct dwarf_expr_piece *p = &c->pieces[i]; | |
d3b1e874 TT |
1640 | size_t this_size, this_size_bits; |
1641 | long dest_offset_bits, source_offset_bits, source_offset; | |
0d45f56e | 1642 | const gdb_byte *intermediate_buffer; |
d3b1e874 TT |
1643 | |
1644 | /* Compute size, source, and destination offsets for copying, in | |
1645 | bits. */ | |
1646 | this_size_bits = p->size; | |
1647 | if (bits_to_skip > 0 && bits_to_skip >= this_size_bits) | |
afd74c5f | 1648 | { |
d3b1e874 | 1649 | bits_to_skip -= this_size_bits; |
afd74c5f TT |
1650 | continue; |
1651 | } | |
d3b1e874 | 1652 | if (bits_to_skip > 0) |
afd74c5f | 1653 | { |
d3b1e874 TT |
1654 | dest_offset_bits = 0; |
1655 | source_offset_bits = bits_to_skip; | |
1656 | this_size_bits -= bits_to_skip; | |
1657 | bits_to_skip = 0; | |
afd74c5f TT |
1658 | } |
1659 | else | |
1660 | { | |
d3b1e874 TT |
1661 | dest_offset_bits = offset; |
1662 | source_offset_bits = 0; | |
afd74c5f | 1663 | } |
5bd1ef56 TT |
1664 | if (this_size_bits > type_len - offset) |
1665 | this_size_bits = type_len - offset; | |
9a619af0 | 1666 | |
d3b1e874 TT |
1667 | this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8; |
1668 | source_offset = source_offset_bits / 8; | |
1669 | if (buffer_size < this_size) | |
1670 | { | |
1671 | buffer_size = this_size; | |
1672 | buffer = xrealloc (buffer, buffer_size); | |
1673 | } | |
1674 | intermediate_buffer = buffer; | |
1675 | ||
1676 | /* Copy from the source to DEST_BUFFER. */ | |
cec03d70 | 1677 | switch (p->location) |
052b9502 | 1678 | { |
cec03d70 TT |
1679 | case DWARF_VALUE_REGISTER: |
1680 | { | |
1681 | struct gdbarch *arch = get_frame_arch (frame); | |
8a9b8146 | 1682 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, p->v.regno); |
afd74c5f | 1683 | int reg_offset = source_offset; |
dcbf108f UW |
1684 | |
1685 | if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG | |
afd74c5f | 1686 | && this_size < register_size (arch, gdb_regnum)) |
d3b1e874 TT |
1687 | { |
1688 | /* Big-endian, and we want less than full size. */ | |
1689 | reg_offset = register_size (arch, gdb_regnum) - this_size; | |
1690 | /* We want the lower-order THIS_SIZE_BITS of the bytes | |
1691 | we extract from the register. */ | |
1692 | source_offset_bits += 8 * this_size - this_size_bits; | |
1693 | } | |
dcbf108f | 1694 | |
63b4f126 MGD |
1695 | if (gdb_regnum != -1) |
1696 | { | |
8dccd430 PA |
1697 | int optim, unavail; |
1698 | ||
1699 | if (!get_frame_register_bytes (frame, gdb_regnum, reg_offset, | |
1700 | this_size, buffer, | |
1701 | &optim, &unavail)) | |
1702 | { | |
1703 | /* Just so garbage doesn't ever shine through. */ | |
1704 | memset (buffer, 0, this_size); | |
1705 | ||
1706 | if (optim) | |
1707 | set_value_optimized_out (v, 1); | |
1708 | if (unavail) | |
bdf22206 | 1709 | mark_value_bits_unavailable (v, offset, this_size_bits); |
8dccd430 | 1710 | } |
63b4f126 MGD |
1711 | } |
1712 | else | |
1713 | { | |
1714 | error (_("Unable to access DWARF register number %s"), | |
8a9b8146 | 1715 | paddress (arch, p->v.regno)); |
63b4f126 | 1716 | } |
cec03d70 TT |
1717 | } |
1718 | break; | |
1719 | ||
1720 | case DWARF_VALUE_MEMORY: | |
e6ca34fc PA |
1721 | read_value_memory (v, offset, |
1722 | p->v.mem.in_stack_memory, | |
1723 | p->v.mem.addr + source_offset, | |
1724 | buffer, this_size); | |
cec03d70 TT |
1725 | break; |
1726 | ||
1727 | case DWARF_VALUE_STACK: | |
1728 | { | |
afd74c5f | 1729 | size_t n = this_size; |
9a619af0 | 1730 | |
afd74c5f TT |
1731 | if (n > c->addr_size - source_offset) |
1732 | n = (c->addr_size >= source_offset | |
1733 | ? c->addr_size - source_offset | |
1734 | : 0); | |
1735 | if (n == 0) | |
1736 | { | |
1737 | /* Nothing. */ | |
1738 | } | |
afd74c5f TT |
1739 | else |
1740 | { | |
8a9b8146 | 1741 | const gdb_byte *val_bytes = value_contents_all (p->v.value); |
afd74c5f | 1742 | |
8a9b8146 | 1743 | intermediate_buffer = val_bytes + source_offset; |
afd74c5f | 1744 | } |
cec03d70 TT |
1745 | } |
1746 | break; | |
1747 | ||
1748 | case DWARF_VALUE_LITERAL: | |
1749 | { | |
afd74c5f TT |
1750 | size_t n = this_size; |
1751 | ||
1752 | if (n > p->v.literal.length - source_offset) | |
1753 | n = (p->v.literal.length >= source_offset | |
1754 | ? p->v.literal.length - source_offset | |
1755 | : 0); | |
1756 | if (n != 0) | |
d3b1e874 | 1757 | intermediate_buffer = p->v.literal.data + source_offset; |
cec03d70 TT |
1758 | } |
1759 | break; | |
1760 | ||
8cf6f0b1 TT |
1761 | /* These bits show up as zeros -- but do not cause the value |
1762 | to be considered optimized-out. */ | |
1763 | case DWARF_VALUE_IMPLICIT_POINTER: | |
1764 | break; | |
1765 | ||
cb826367 | 1766 | case DWARF_VALUE_OPTIMIZED_OUT: |
0e03807e | 1767 | set_value_optimized_out (v, 1); |
cb826367 TT |
1768 | break; |
1769 | ||
cec03d70 TT |
1770 | default: |
1771 | internal_error (__FILE__, __LINE__, _("invalid location type")); | |
052b9502 | 1772 | } |
d3b1e874 | 1773 | |
8cf6f0b1 TT |
1774 | if (p->location != DWARF_VALUE_OPTIMIZED_OUT |
1775 | && p->location != DWARF_VALUE_IMPLICIT_POINTER) | |
d3b1e874 TT |
1776 | copy_bitwise (contents, dest_offset_bits, |
1777 | intermediate_buffer, source_offset_bits % 8, | |
1778 | this_size_bits, bits_big_endian); | |
1779 | ||
1780 | offset += this_size_bits; | |
052b9502 | 1781 | } |
d3b1e874 TT |
1782 | |
1783 | do_cleanups (cleanup); | |
052b9502 NF |
1784 | } |
1785 | ||
1786 | static void | |
1787 | write_pieced_value (struct value *to, struct value *from) | |
1788 | { | |
1789 | int i; | |
1790 | long offset = 0; | |
d3b1e874 | 1791 | ULONGEST bits_to_skip; |
afd74c5f | 1792 | const gdb_byte *contents; |
3e43a32a MS |
1793 | struct piece_closure *c |
1794 | = (struct piece_closure *) value_computed_closure (to); | |
052b9502 | 1795 | struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (to)); |
afd74c5f | 1796 | size_t type_len; |
d3b1e874 | 1797 | size_t buffer_size = 0; |
948f8e3d | 1798 | gdb_byte *buffer = NULL; |
d3b1e874 TT |
1799 | struct cleanup *cleanup; |
1800 | int bits_big_endian | |
1801 | = gdbarch_bits_big_endian (get_type_arch (value_type (to))); | |
052b9502 NF |
1802 | |
1803 | if (frame == NULL) | |
1804 | { | |
1805 | set_value_optimized_out (to, 1); | |
1806 | return; | |
1807 | } | |
1808 | ||
d3b1e874 TT |
1809 | cleanup = make_cleanup (free_current_contents, &buffer); |
1810 | ||
afd74c5f | 1811 | contents = value_contents (from); |
d3b1e874 | 1812 | bits_to_skip = 8 * value_offset (to); |
0e03807e TT |
1813 | if (value_bitsize (to)) |
1814 | { | |
1815 | bits_to_skip += value_bitpos (to); | |
1816 | type_len = value_bitsize (to); | |
1817 | } | |
1818 | else | |
1819 | type_len = 8 * TYPE_LENGTH (value_type (to)); | |
1820 | ||
afd74c5f | 1821 | for (i = 0; i < c->n_pieces && offset < type_len; i++) |
052b9502 NF |
1822 | { |
1823 | struct dwarf_expr_piece *p = &c->pieces[i]; | |
d3b1e874 TT |
1824 | size_t this_size_bits, this_size; |
1825 | long dest_offset_bits, source_offset_bits, dest_offset, source_offset; | |
1826 | int need_bitwise; | |
1827 | const gdb_byte *source_buffer; | |
afd74c5f | 1828 | |
d3b1e874 TT |
1829 | this_size_bits = p->size; |
1830 | if (bits_to_skip > 0 && bits_to_skip >= this_size_bits) | |
afd74c5f | 1831 | { |
d3b1e874 | 1832 | bits_to_skip -= this_size_bits; |
afd74c5f TT |
1833 | continue; |
1834 | } | |
d3b1e874 TT |
1835 | if (this_size_bits > type_len - offset) |
1836 | this_size_bits = type_len - offset; | |
1837 | if (bits_to_skip > 0) | |
afd74c5f | 1838 | { |
d3b1e874 TT |
1839 | dest_offset_bits = bits_to_skip; |
1840 | source_offset_bits = 0; | |
1841 | this_size_bits -= bits_to_skip; | |
1842 | bits_to_skip = 0; | |
afd74c5f TT |
1843 | } |
1844 | else | |
1845 | { | |
d3b1e874 TT |
1846 | dest_offset_bits = 0; |
1847 | source_offset_bits = offset; | |
1848 | } | |
1849 | ||
1850 | this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8; | |
1851 | source_offset = source_offset_bits / 8; | |
1852 | dest_offset = dest_offset_bits / 8; | |
1853 | if (dest_offset_bits % 8 == 0 && source_offset_bits % 8 == 0) | |
1854 | { | |
1855 | source_buffer = contents + source_offset; | |
1856 | need_bitwise = 0; | |
1857 | } | |
1858 | else | |
1859 | { | |
1860 | if (buffer_size < this_size) | |
1861 | { | |
1862 | buffer_size = this_size; | |
1863 | buffer = xrealloc (buffer, buffer_size); | |
1864 | } | |
1865 | source_buffer = buffer; | |
1866 | need_bitwise = 1; | |
afd74c5f | 1867 | } |
9a619af0 | 1868 | |
cec03d70 | 1869 | switch (p->location) |
052b9502 | 1870 | { |
cec03d70 TT |
1871 | case DWARF_VALUE_REGISTER: |
1872 | { | |
1873 | struct gdbarch *arch = get_frame_arch (frame); | |
8a9b8146 | 1874 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, p->v.regno); |
afd74c5f | 1875 | int reg_offset = dest_offset; |
dcbf108f UW |
1876 | |
1877 | if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG | |
afd74c5f | 1878 | && this_size <= register_size (arch, gdb_regnum)) |
dcbf108f | 1879 | /* Big-endian, and we want less than full size. */ |
afd74c5f | 1880 | reg_offset = register_size (arch, gdb_regnum) - this_size; |
dcbf108f | 1881 | |
63b4f126 MGD |
1882 | if (gdb_regnum != -1) |
1883 | { | |
d3b1e874 TT |
1884 | if (need_bitwise) |
1885 | { | |
8dccd430 PA |
1886 | int optim, unavail; |
1887 | ||
1888 | if (!get_frame_register_bytes (frame, gdb_regnum, reg_offset, | |
1889 | this_size, buffer, | |
1890 | &optim, &unavail)) | |
1891 | { | |
1892 | if (optim) | |
710409a2 PA |
1893 | throw_error (OPTIMIZED_OUT_ERROR, |
1894 | _("Can't do read-modify-write to " | |
1895 | "update bitfield; containing word " | |
1896 | "has been optimized out")); | |
8dccd430 PA |
1897 | if (unavail) |
1898 | throw_error (NOT_AVAILABLE_ERROR, | |
1899 | _("Can't do read-modify-write to update " | |
1900 | "bitfield; containing word " | |
1901 | "is unavailable")); | |
1902 | } | |
d3b1e874 TT |
1903 | copy_bitwise (buffer, dest_offset_bits, |
1904 | contents, source_offset_bits, | |
1905 | this_size_bits, | |
1906 | bits_big_endian); | |
1907 | } | |
1908 | ||
63b4f126 | 1909 | put_frame_register_bytes (frame, gdb_regnum, reg_offset, |
d3b1e874 | 1910 | this_size, source_buffer); |
63b4f126 MGD |
1911 | } |
1912 | else | |
1913 | { | |
1914 | error (_("Unable to write to DWARF register number %s"), | |
8a9b8146 | 1915 | paddress (arch, p->v.regno)); |
63b4f126 | 1916 | } |
cec03d70 TT |
1917 | } |
1918 | break; | |
1919 | case DWARF_VALUE_MEMORY: | |
d3b1e874 TT |
1920 | if (need_bitwise) |
1921 | { | |
1922 | /* Only the first and last bytes can possibly have any | |
1923 | bits reused. */ | |
f2c7657e UW |
1924 | read_memory (p->v.mem.addr + dest_offset, buffer, 1); |
1925 | read_memory (p->v.mem.addr + dest_offset + this_size - 1, | |
d3b1e874 TT |
1926 | buffer + this_size - 1, 1); |
1927 | copy_bitwise (buffer, dest_offset_bits, | |
1928 | contents, source_offset_bits, | |
1929 | this_size_bits, | |
1930 | bits_big_endian); | |
1931 | } | |
1932 | ||
f2c7657e | 1933 | write_memory (p->v.mem.addr + dest_offset, |
d3b1e874 | 1934 | source_buffer, this_size); |
cec03d70 TT |
1935 | break; |
1936 | default: | |
1937 | set_value_optimized_out (to, 1); | |
0e03807e | 1938 | break; |
052b9502 | 1939 | } |
d3b1e874 | 1940 | offset += this_size_bits; |
052b9502 | 1941 | } |
d3b1e874 | 1942 | |
d3b1e874 | 1943 | do_cleanups (cleanup); |
052b9502 NF |
1944 | } |
1945 | ||
8cf6f0b1 TT |
1946 | /* A helper function that checks bit validity in a pieced value. |
1947 | CHECK_FOR indicates the kind of validity checking. | |
1948 | DWARF_VALUE_MEMORY means to check whether any bit is valid. | |
1949 | DWARF_VALUE_OPTIMIZED_OUT means to check whether any bit is | |
1950 | optimized out. | |
1951 | DWARF_VALUE_IMPLICIT_POINTER means to check whether the bits are an | |
1952 | implicit pointer. */ | |
1953 | ||
0e03807e TT |
1954 | static int |
1955 | check_pieced_value_bits (const struct value *value, int bit_offset, | |
8cf6f0b1 TT |
1956 | int bit_length, |
1957 | enum dwarf_value_location check_for) | |
0e03807e TT |
1958 | { |
1959 | struct piece_closure *c | |
1960 | = (struct piece_closure *) value_computed_closure (value); | |
1961 | int i; | |
8cf6f0b1 TT |
1962 | int validity = (check_for == DWARF_VALUE_MEMORY |
1963 | || check_for == DWARF_VALUE_IMPLICIT_POINTER); | |
0e03807e TT |
1964 | |
1965 | bit_offset += 8 * value_offset (value); | |
1966 | if (value_bitsize (value)) | |
1967 | bit_offset += value_bitpos (value); | |
1968 | ||
1969 | for (i = 0; i < c->n_pieces && bit_length > 0; i++) | |
1970 | { | |
1971 | struct dwarf_expr_piece *p = &c->pieces[i]; | |
1972 | size_t this_size_bits = p->size; | |
1973 | ||
1974 | if (bit_offset > 0) | |
1975 | { | |
1976 | if (bit_offset >= this_size_bits) | |
1977 | { | |
1978 | bit_offset -= this_size_bits; | |
1979 | continue; | |
1980 | } | |
1981 | ||
1982 | bit_length -= this_size_bits - bit_offset; | |
1983 | bit_offset = 0; | |
1984 | } | |
1985 | else | |
1986 | bit_length -= this_size_bits; | |
1987 | ||
8cf6f0b1 TT |
1988 | if (check_for == DWARF_VALUE_IMPLICIT_POINTER) |
1989 | { | |
1990 | if (p->location != DWARF_VALUE_IMPLICIT_POINTER) | |
1991 | return 0; | |
1992 | } | |
1993 | else if (p->location == DWARF_VALUE_OPTIMIZED_OUT | |
1994 | || p->location == DWARF_VALUE_IMPLICIT_POINTER) | |
0e03807e TT |
1995 | { |
1996 | if (validity) | |
1997 | return 0; | |
1998 | } | |
1999 | else | |
2000 | { | |
2001 | if (!validity) | |
2002 | return 1; | |
2003 | } | |
2004 | } | |
2005 | ||
2006 | return validity; | |
2007 | } | |
2008 | ||
2009 | static int | |
2010 | check_pieced_value_validity (const struct value *value, int bit_offset, | |
2011 | int bit_length) | |
2012 | { | |
8cf6f0b1 TT |
2013 | return check_pieced_value_bits (value, bit_offset, bit_length, |
2014 | DWARF_VALUE_MEMORY); | |
0e03807e TT |
2015 | } |
2016 | ||
2017 | static int | |
2018 | check_pieced_value_invalid (const struct value *value) | |
2019 | { | |
2020 | return check_pieced_value_bits (value, 0, | |
8cf6f0b1 TT |
2021 | 8 * TYPE_LENGTH (value_type (value)), |
2022 | DWARF_VALUE_OPTIMIZED_OUT); | |
2023 | } | |
2024 | ||
2025 | /* An implementation of an lval_funcs method to see whether a value is | |
2026 | a synthetic pointer. */ | |
2027 | ||
2028 | static int | |
2029 | check_pieced_synthetic_pointer (const struct value *value, int bit_offset, | |
2030 | int bit_length) | |
2031 | { | |
2032 | return check_pieced_value_bits (value, bit_offset, bit_length, | |
2033 | DWARF_VALUE_IMPLICIT_POINTER); | |
2034 | } | |
2035 | ||
2036 | /* A wrapper function for get_frame_address_in_block. */ | |
2037 | ||
2038 | static CORE_ADDR | |
2039 | get_frame_address_in_block_wrapper (void *baton) | |
2040 | { | |
2041 | return get_frame_address_in_block (baton); | |
2042 | } | |
2043 | ||
2044 | /* An implementation of an lval_funcs method to indirect through a | |
2045 | pointer. This handles the synthetic pointer case when needed. */ | |
2046 | ||
2047 | static struct value * | |
2048 | indirect_pieced_value (struct value *value) | |
2049 | { | |
2050 | struct piece_closure *c | |
2051 | = (struct piece_closure *) value_computed_closure (value); | |
2052 | struct type *type; | |
2053 | struct frame_info *frame; | |
2054 | struct dwarf2_locexpr_baton baton; | |
2055 | int i, bit_offset, bit_length; | |
2056 | struct dwarf_expr_piece *piece = NULL; | |
8cf6f0b1 TT |
2057 | LONGEST byte_offset; |
2058 | ||
0e37a63c | 2059 | type = check_typedef (value_type (value)); |
8cf6f0b1 TT |
2060 | if (TYPE_CODE (type) != TYPE_CODE_PTR) |
2061 | return NULL; | |
2062 | ||
2063 | bit_length = 8 * TYPE_LENGTH (type); | |
2064 | bit_offset = 8 * value_offset (value); | |
2065 | if (value_bitsize (value)) | |
2066 | bit_offset += value_bitpos (value); | |
2067 | ||
2068 | for (i = 0; i < c->n_pieces && bit_length > 0; i++) | |
2069 | { | |
2070 | struct dwarf_expr_piece *p = &c->pieces[i]; | |
2071 | size_t this_size_bits = p->size; | |
2072 | ||
2073 | if (bit_offset > 0) | |
2074 | { | |
2075 | if (bit_offset >= this_size_bits) | |
2076 | { | |
2077 | bit_offset -= this_size_bits; | |
2078 | continue; | |
2079 | } | |
2080 | ||
2081 | bit_length -= this_size_bits - bit_offset; | |
2082 | bit_offset = 0; | |
2083 | } | |
2084 | else | |
2085 | bit_length -= this_size_bits; | |
2086 | ||
2087 | if (p->location != DWARF_VALUE_IMPLICIT_POINTER) | |
2088 | return NULL; | |
2089 | ||
2090 | if (bit_length != 0) | |
2091 | error (_("Invalid use of DW_OP_GNU_implicit_pointer")); | |
2092 | ||
2093 | piece = p; | |
2094 | break; | |
2095 | } | |
2096 | ||
2097 | frame = get_selected_frame (_("No frame selected.")); | |
543305c9 | 2098 | |
5bd1ef56 TT |
2099 | /* This is an offset requested by GDB, such as value subscripts. |
2100 | However, due to how synthetic pointers are implemented, this is | |
2101 | always presented to us as a pointer type. This means we have to | |
2102 | sign-extend it manually as appropriate. */ | |
8cf6f0b1 | 2103 | byte_offset = value_as_address (value); |
5bd1ef56 TT |
2104 | if (TYPE_LENGTH (value_type (value)) < sizeof (LONGEST)) |
2105 | byte_offset = gdb_sign_extend (byte_offset, | |
2106 | 8 * TYPE_LENGTH (value_type (value))); | |
2107 | byte_offset += piece->v.ptr.offset; | |
8cf6f0b1 | 2108 | |
e0e40094 | 2109 | gdb_assert (piece); |
8b9737bf TT |
2110 | baton |
2111 | = dwarf2_fetch_die_loc_sect_off (piece->v.ptr.die, c->per_cu, | |
2112 | get_frame_address_in_block_wrapper, | |
2113 | frame); | |
8cf6f0b1 | 2114 | |
b6807d98 TT |
2115 | if (baton.data != NULL) |
2116 | return dwarf2_evaluate_loc_desc_full (TYPE_TARGET_TYPE (type), frame, | |
2117 | baton.data, baton.size, baton.per_cu, | |
5bd1ef56 | 2118 | byte_offset); |
b6807d98 TT |
2119 | |
2120 | { | |
2121 | struct obstack temp_obstack; | |
2122 | struct cleanup *cleanup; | |
2123 | const gdb_byte *bytes; | |
2124 | LONGEST len; | |
2125 | struct value *result; | |
2126 | ||
2127 | obstack_init (&temp_obstack); | |
2128 | cleanup = make_cleanup_obstack_free (&temp_obstack); | |
2129 | ||
2130 | bytes = dwarf2_fetch_constant_bytes (piece->v.ptr.die, c->per_cu, | |
2131 | &temp_obstack, &len); | |
2132 | if (bytes == NULL) | |
2133 | result = allocate_optimized_out_value (TYPE_TARGET_TYPE (type)); | |
2134 | else | |
2135 | { | |
2136 | if (byte_offset < 0 | |
2137 | || byte_offset + TYPE_LENGTH (TYPE_TARGET_TYPE (type)) > len) | |
2138 | invalid_synthetic_pointer (); | |
2139 | bytes += byte_offset; | |
2140 | result = value_from_contents (TYPE_TARGET_TYPE (type), bytes); | |
2141 | } | |
2142 | ||
2143 | do_cleanups (cleanup); | |
2144 | return result; | |
2145 | } | |
0e03807e TT |
2146 | } |
2147 | ||
052b9502 | 2148 | static void * |
0e03807e | 2149 | copy_pieced_value_closure (const struct value *v) |
052b9502 | 2150 | { |
3e43a32a MS |
2151 | struct piece_closure *c |
2152 | = (struct piece_closure *) value_computed_closure (v); | |
052b9502 | 2153 | |
88bfdde4 TT |
2154 | ++c->refc; |
2155 | return c; | |
052b9502 NF |
2156 | } |
2157 | ||
2158 | static void | |
2159 | free_pieced_value_closure (struct value *v) | |
2160 | { | |
3e43a32a MS |
2161 | struct piece_closure *c |
2162 | = (struct piece_closure *) value_computed_closure (v); | |
052b9502 | 2163 | |
88bfdde4 TT |
2164 | --c->refc; |
2165 | if (c->refc == 0) | |
2166 | { | |
8a9b8146 TT |
2167 | int i; |
2168 | ||
2169 | for (i = 0; i < c->n_pieces; ++i) | |
2170 | if (c->pieces[i].location == DWARF_VALUE_STACK) | |
2171 | value_free (c->pieces[i].v.value); | |
2172 | ||
88bfdde4 TT |
2173 | xfree (c->pieces); |
2174 | xfree (c); | |
2175 | } | |
052b9502 NF |
2176 | } |
2177 | ||
2178 | /* Functions for accessing a variable described by DW_OP_piece. */ | |
c8f2448a | 2179 | static const struct lval_funcs pieced_value_funcs = { |
052b9502 NF |
2180 | read_pieced_value, |
2181 | write_pieced_value, | |
0e03807e TT |
2182 | check_pieced_value_validity, |
2183 | check_pieced_value_invalid, | |
8cf6f0b1 | 2184 | indirect_pieced_value, |
a471c594 | 2185 | NULL, /* coerce_ref */ |
8cf6f0b1 | 2186 | check_pieced_synthetic_pointer, |
052b9502 NF |
2187 | copy_pieced_value_closure, |
2188 | free_pieced_value_closure | |
2189 | }; | |
2190 | ||
9e8b7a03 JK |
2191 | /* Virtual method table for dwarf2_evaluate_loc_desc_full below. */ |
2192 | ||
2193 | static const struct dwarf_expr_context_funcs dwarf_expr_ctx_funcs = | |
2194 | { | |
b1370418 | 2195 | dwarf_expr_read_addr_from_reg, |
0acf8b65 | 2196 | dwarf_expr_get_reg_value, |
9e8b7a03 JK |
2197 | dwarf_expr_read_mem, |
2198 | dwarf_expr_frame_base, | |
2199 | dwarf_expr_frame_cfa, | |
2200 | dwarf_expr_frame_pc, | |
2201 | dwarf_expr_tls_address, | |
2202 | dwarf_expr_dwarf_call, | |
8e3b41a9 | 2203 | dwarf_expr_get_base_type, |
3019eac3 DE |
2204 | dwarf_expr_push_dwarf_reg_entry_value, |
2205 | dwarf_expr_get_addr_index | |
9e8b7a03 JK |
2206 | }; |
2207 | ||
4c2df51b | 2208 | /* Evaluate a location description, starting at DATA and with length |
8cf6f0b1 TT |
2209 | SIZE, to find the current location of variable of TYPE in the |
2210 | context of FRAME. BYTE_OFFSET is applied after the contents are | |
2211 | computed. */ | |
a2d33775 | 2212 | |
8cf6f0b1 TT |
2213 | static struct value * |
2214 | dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame, | |
56eb65bd | 2215 | const gdb_byte *data, size_t size, |
8cf6f0b1 TT |
2216 | struct dwarf2_per_cu_data *per_cu, |
2217 | LONGEST byte_offset) | |
4c2df51b | 2218 | { |
4c2df51b DJ |
2219 | struct value *retval; |
2220 | struct dwarf_expr_baton baton; | |
2221 | struct dwarf_expr_context *ctx; | |
72fc29ff | 2222 | struct cleanup *old_chain, *value_chain; |
ac56253d | 2223 | struct objfile *objfile = dwarf2_per_cu_objfile (per_cu); |
79e1a869 | 2224 | volatile struct gdb_exception ex; |
4c2df51b | 2225 | |
8cf6f0b1 TT |
2226 | if (byte_offset < 0) |
2227 | invalid_synthetic_pointer (); | |
2228 | ||
0d53c4c4 | 2229 | if (size == 0) |
a7035dbb | 2230 | return allocate_optimized_out_value (type); |
0d53c4c4 | 2231 | |
4c2df51b | 2232 | baton.frame = frame; |
17ea53c3 | 2233 | baton.per_cu = per_cu; |
4c2df51b DJ |
2234 | |
2235 | ctx = new_dwarf_expr_context (); | |
4a227398 | 2236 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
72fc29ff | 2237 | value_chain = make_cleanup_value_free_to_mark (value_mark ()); |
4a227398 | 2238 | |
ac56253d | 2239 | ctx->gdbarch = get_objfile_arch (objfile); |
ae0d2f24 | 2240 | ctx->addr_size = dwarf2_per_cu_addr_size (per_cu); |
181cebd4 | 2241 | ctx->ref_addr_size = dwarf2_per_cu_ref_addr_size (per_cu); |
9aa1f1e3 | 2242 | ctx->offset = dwarf2_per_cu_text_offset (per_cu); |
4c2df51b | 2243 | ctx->baton = &baton; |
9e8b7a03 | 2244 | ctx->funcs = &dwarf_expr_ctx_funcs; |
4c2df51b | 2245 | |
79e1a869 PA |
2246 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
2247 | { | |
2248 | dwarf_expr_eval (ctx, data, size); | |
2249 | } | |
2250 | if (ex.reason < 0) | |
2251 | { | |
2252 | if (ex.error == NOT_AVAILABLE_ERROR) | |
2253 | { | |
72fc29ff | 2254 | do_cleanups (old_chain); |
79e1a869 PA |
2255 | retval = allocate_value (type); |
2256 | mark_value_bytes_unavailable (retval, 0, TYPE_LENGTH (type)); | |
2257 | return retval; | |
2258 | } | |
8e3b41a9 JK |
2259 | else if (ex.error == NO_ENTRY_VALUE_ERROR) |
2260 | { | |
2261 | if (entry_values_debug) | |
2262 | exception_print (gdb_stdout, ex); | |
2263 | do_cleanups (old_chain); | |
2264 | return allocate_optimized_out_value (type); | |
2265 | } | |
79e1a869 PA |
2266 | else |
2267 | throw_exception (ex); | |
2268 | } | |
2269 | ||
87808bd6 JB |
2270 | if (ctx->num_pieces > 0) |
2271 | { | |
052b9502 NF |
2272 | struct piece_closure *c; |
2273 | struct frame_id frame_id = get_frame_id (frame); | |
8cf6f0b1 TT |
2274 | ULONGEST bit_size = 0; |
2275 | int i; | |
052b9502 | 2276 | |
8cf6f0b1 TT |
2277 | for (i = 0; i < ctx->num_pieces; ++i) |
2278 | bit_size += ctx->pieces[i].size; | |
2279 | if (8 * (byte_offset + TYPE_LENGTH (type)) > bit_size) | |
2280 | invalid_synthetic_pointer (); | |
2281 | ||
2282 | c = allocate_piece_closure (per_cu, ctx->num_pieces, ctx->pieces, | |
6063c216 | 2283 | ctx->addr_size); |
72fc29ff TT |
2284 | /* We must clean up the value chain after creating the piece |
2285 | closure but before allocating the result. */ | |
2286 | do_cleanups (value_chain); | |
a2d33775 | 2287 | retval = allocate_computed_value (type, &pieced_value_funcs, c); |
052b9502 | 2288 | VALUE_FRAME_ID (retval) = frame_id; |
8cf6f0b1 | 2289 | set_value_offset (retval, byte_offset); |
87808bd6 | 2290 | } |
4c2df51b DJ |
2291 | else |
2292 | { | |
cec03d70 TT |
2293 | switch (ctx->location) |
2294 | { | |
2295 | case DWARF_VALUE_REGISTER: | |
2296 | { | |
2297 | struct gdbarch *arch = get_frame_arch (frame); | |
7c33b57c PA |
2298 | int dwarf_regnum |
2299 | = longest_to_int (value_as_long (dwarf_expr_fetch (ctx, 0))); | |
cec03d70 | 2300 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_regnum); |
9a619af0 | 2301 | |
8cf6f0b1 TT |
2302 | if (byte_offset != 0) |
2303 | error (_("cannot use offset on synthetic pointer to register")); | |
72fc29ff | 2304 | do_cleanups (value_chain); |
901461f8 | 2305 | if (gdb_regnum == -1) |
7c33b57c PA |
2306 | error (_("Unable to access DWARF register number %d"), |
2307 | dwarf_regnum); | |
901461f8 PA |
2308 | retval = value_from_register (type, gdb_regnum, frame); |
2309 | if (value_optimized_out (retval)) | |
2310 | { | |
2311 | /* This means the register has undefined value / was | |
2312 | not saved. As we're computing the location of some | |
2313 | variable etc. in the program, not a value for | |
2314 | inspecting a register ($pc, $sp, etc.), return a | |
2315 | generic optimized out value instead, so that we show | |
2316 | <optimized out> instead of <not saved>. */ | |
2317 | do_cleanups (value_chain); | |
2318 | retval = allocate_optimized_out_value (type); | |
2319 | } | |
cec03d70 TT |
2320 | } |
2321 | break; | |
2322 | ||
2323 | case DWARF_VALUE_MEMORY: | |
2324 | { | |
f2c7657e | 2325 | CORE_ADDR address = dwarf_expr_fetch_address (ctx, 0); |
44353522 | 2326 | int in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0); |
cec03d70 | 2327 | |
72fc29ff | 2328 | do_cleanups (value_chain); |
08039c9e | 2329 | retval = value_at_lazy (type, address + byte_offset); |
44353522 DE |
2330 | if (in_stack_memory) |
2331 | set_value_stack (retval, 1); | |
cec03d70 TT |
2332 | } |
2333 | break; | |
2334 | ||
2335 | case DWARF_VALUE_STACK: | |
2336 | { | |
8a9b8146 TT |
2337 | struct value *value = dwarf_expr_fetch (ctx, 0); |
2338 | gdb_byte *contents; | |
2339 | const gdb_byte *val_bytes; | |
2340 | size_t n = TYPE_LENGTH (value_type (value)); | |
cec03d70 | 2341 | |
8cf6f0b1 TT |
2342 | if (byte_offset + TYPE_LENGTH (type) > n) |
2343 | invalid_synthetic_pointer (); | |
2344 | ||
8a9b8146 TT |
2345 | val_bytes = value_contents_all (value); |
2346 | val_bytes += byte_offset; | |
8cf6f0b1 TT |
2347 | n -= byte_offset; |
2348 | ||
72fc29ff TT |
2349 | /* Preserve VALUE because we are going to free values back |
2350 | to the mark, but we still need the value contents | |
2351 | below. */ | |
2352 | value_incref (value); | |
2353 | do_cleanups (value_chain); | |
2354 | make_cleanup_value_free (value); | |
2355 | ||
a2d33775 | 2356 | retval = allocate_value (type); |
cec03d70 | 2357 | contents = value_contents_raw (retval); |
a2d33775 | 2358 | if (n > TYPE_LENGTH (type)) |
b6cede78 JK |
2359 | { |
2360 | struct gdbarch *objfile_gdbarch = get_objfile_arch (objfile); | |
2361 | ||
2362 | if (gdbarch_byte_order (objfile_gdbarch) == BFD_ENDIAN_BIG) | |
2363 | val_bytes += n - TYPE_LENGTH (type); | |
2364 | n = TYPE_LENGTH (type); | |
2365 | } | |
8a9b8146 | 2366 | memcpy (contents, val_bytes, n); |
cec03d70 TT |
2367 | } |
2368 | break; | |
2369 | ||
2370 | case DWARF_VALUE_LITERAL: | |
2371 | { | |
2372 | bfd_byte *contents; | |
8c814cdd | 2373 | const bfd_byte *ldata; |
cec03d70 TT |
2374 | size_t n = ctx->len; |
2375 | ||
8cf6f0b1 TT |
2376 | if (byte_offset + TYPE_LENGTH (type) > n) |
2377 | invalid_synthetic_pointer (); | |
2378 | ||
72fc29ff | 2379 | do_cleanups (value_chain); |
a2d33775 | 2380 | retval = allocate_value (type); |
cec03d70 | 2381 | contents = value_contents_raw (retval); |
8cf6f0b1 | 2382 | |
8c814cdd | 2383 | ldata = ctx->data + byte_offset; |
8cf6f0b1 TT |
2384 | n -= byte_offset; |
2385 | ||
a2d33775 | 2386 | if (n > TYPE_LENGTH (type)) |
b6cede78 JK |
2387 | { |
2388 | struct gdbarch *objfile_gdbarch = get_objfile_arch (objfile); | |
2389 | ||
2390 | if (gdbarch_byte_order (objfile_gdbarch) == BFD_ENDIAN_BIG) | |
2391 | ldata += n - TYPE_LENGTH (type); | |
2392 | n = TYPE_LENGTH (type); | |
2393 | } | |
8c814cdd | 2394 | memcpy (contents, ldata, n); |
cec03d70 TT |
2395 | } |
2396 | break; | |
2397 | ||
dd90784c | 2398 | case DWARF_VALUE_OPTIMIZED_OUT: |
72fc29ff | 2399 | do_cleanups (value_chain); |
a7035dbb | 2400 | retval = allocate_optimized_out_value (type); |
dd90784c JK |
2401 | break; |
2402 | ||
8cf6f0b1 TT |
2403 | /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced |
2404 | operation by execute_stack_op. */ | |
2405 | case DWARF_VALUE_IMPLICIT_POINTER: | |
cb826367 TT |
2406 | /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context -- |
2407 | it can only be encountered when making a piece. */ | |
cec03d70 TT |
2408 | default: |
2409 | internal_error (__FILE__, __LINE__, _("invalid location type")); | |
2410 | } | |
4c2df51b DJ |
2411 | } |
2412 | ||
42be36b3 CT |
2413 | set_value_initialized (retval, ctx->initialized); |
2414 | ||
4a227398 | 2415 | do_cleanups (old_chain); |
4c2df51b DJ |
2416 | |
2417 | return retval; | |
2418 | } | |
8cf6f0b1 TT |
2419 | |
2420 | /* The exported interface to dwarf2_evaluate_loc_desc_full; it always | |
2421 | passes 0 as the byte_offset. */ | |
2422 | ||
2423 | struct value * | |
2424 | dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame, | |
56eb65bd | 2425 | const gdb_byte *data, size_t size, |
8cf6f0b1 TT |
2426 | struct dwarf2_per_cu_data *per_cu) |
2427 | { | |
2428 | return dwarf2_evaluate_loc_desc_full (type, frame, data, size, per_cu, 0); | |
2429 | } | |
2430 | ||
80180f79 SA |
2431 | /* Evaluates a dwarf expression and stores the result in VAL, expecting |
2432 | that the dwarf expression only produces a single CORE_ADDR. ADDR is a | |
2433 | context (location of a variable) and might be needed to evaluate the | |
2434 | location expression. | |
2435 | Returns 1 on success, 0 otherwise. */ | |
2436 | ||
2437 | static int | |
2438 | dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton *dlbaton, | |
2439 | CORE_ADDR addr, CORE_ADDR *valp) | |
2440 | { | |
2441 | struct dwarf_expr_context *ctx; | |
2442 | struct dwarf_expr_baton baton; | |
2443 | struct objfile *objfile; | |
2444 | struct cleanup *cleanup; | |
2445 | ||
2446 | if (dlbaton == NULL || dlbaton->size == 0) | |
2447 | return 0; | |
2448 | ||
2449 | ctx = new_dwarf_expr_context (); | |
2450 | cleanup = make_cleanup_free_dwarf_expr_context (ctx); | |
2451 | ||
2452 | baton.frame = get_selected_frame (NULL); | |
2453 | baton.per_cu = dlbaton->per_cu; | |
2454 | ||
2455 | objfile = dwarf2_per_cu_objfile (dlbaton->per_cu); | |
2456 | ||
2457 | ctx->gdbarch = get_objfile_arch (objfile); | |
2458 | ctx->addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); | |
2459 | ctx->ref_addr_size = dwarf2_per_cu_ref_addr_size (dlbaton->per_cu); | |
2460 | ctx->offset = dwarf2_per_cu_text_offset (dlbaton->per_cu); | |
2461 | ctx->funcs = &dwarf_expr_ctx_funcs; | |
2462 | ctx->baton = &baton; | |
2463 | ||
2464 | dwarf_expr_eval (ctx, dlbaton->data, dlbaton->size); | |
2465 | ||
2466 | switch (ctx->location) | |
2467 | { | |
2468 | case DWARF_VALUE_REGISTER: | |
2469 | case DWARF_VALUE_MEMORY: | |
2470 | case DWARF_VALUE_STACK: | |
2471 | *valp = dwarf_expr_fetch_address (ctx, 0); | |
2472 | if (ctx->location == DWARF_VALUE_REGISTER) | |
2473 | *valp = dwarf_expr_read_addr_from_reg (&baton, *valp); | |
2474 | do_cleanups (cleanup); | |
2475 | return 1; | |
2476 | case DWARF_VALUE_LITERAL: | |
2477 | *valp = extract_signed_integer (ctx->data, ctx->len, | |
2478 | gdbarch_byte_order (ctx->gdbarch)); | |
2479 | do_cleanups (cleanup); | |
2480 | return 1; | |
2481 | /* Unsupported dwarf values. */ | |
2482 | case DWARF_VALUE_OPTIMIZED_OUT: | |
2483 | case DWARF_VALUE_IMPLICIT_POINTER: | |
2484 | break; | |
2485 | } | |
2486 | ||
2487 | do_cleanups (cleanup); | |
2488 | return 0; | |
2489 | } | |
2490 | ||
2491 | /* See dwarf2loc.h. */ | |
2492 | ||
2493 | int | |
2494 | dwarf2_evaluate_property (const struct dynamic_prop *prop, CORE_ADDR address, | |
2495 | CORE_ADDR *value) | |
2496 | { | |
2497 | if (prop == NULL) | |
2498 | return 0; | |
2499 | ||
2500 | switch (prop->kind) | |
2501 | { | |
2502 | case PROP_LOCEXPR: | |
2503 | { | |
2504 | const struct dwarf2_property_baton *baton = prop->data.baton; | |
2505 | ||
2506 | if (dwarf2_locexpr_baton_eval (&baton->locexpr, address, value)) | |
2507 | { | |
2508 | if (baton->referenced_type) | |
2509 | { | |
2510 | struct value *val = value_at (baton->referenced_type, *value); | |
2511 | ||
2512 | *value = value_as_address (val); | |
2513 | } | |
2514 | return 1; | |
2515 | } | |
2516 | } | |
2517 | break; | |
2518 | ||
2519 | case PROP_LOCLIST: | |
2520 | { | |
2521 | struct dwarf2_property_baton *baton = prop->data.baton; | |
2522 | struct frame_info *frame = get_selected_frame (NULL); | |
2523 | CORE_ADDR pc = get_frame_address_in_block (frame); | |
2524 | const gdb_byte *data; | |
2525 | struct value *val; | |
2526 | size_t size; | |
2527 | ||
2528 | data = dwarf2_find_location_expression (&baton->loclist, &size, pc); | |
2529 | if (data != NULL) | |
2530 | { | |
2531 | val = dwarf2_evaluate_loc_desc (baton->referenced_type, frame, data, | |
2532 | size, baton->loclist.per_cu); | |
2533 | if (!value_optimized_out (val)) | |
2534 | { | |
2535 | *value = value_as_address (val); | |
2536 | return 1; | |
2537 | } | |
2538 | } | |
2539 | } | |
2540 | break; | |
2541 | ||
2542 | case PROP_CONST: | |
2543 | *value = prop->data.const_val; | |
2544 | return 1; | |
2545 | } | |
2546 | ||
2547 | return 0; | |
2548 | } | |
2549 | ||
4c2df51b DJ |
2550 | \f |
2551 | /* Helper functions and baton for dwarf2_loc_desc_needs_frame. */ | |
2552 | ||
2553 | struct needs_frame_baton | |
2554 | { | |
2555 | int needs_frame; | |
17ea53c3 | 2556 | struct dwarf2_per_cu_data *per_cu; |
4c2df51b DJ |
2557 | }; |
2558 | ||
2559 | /* Reads from registers do require a frame. */ | |
2560 | static CORE_ADDR | |
b1370418 | 2561 | needs_frame_read_addr_from_reg (void *baton, int regnum) |
4c2df51b DJ |
2562 | { |
2563 | struct needs_frame_baton *nf_baton = baton; | |
9a619af0 | 2564 | |
4c2df51b DJ |
2565 | nf_baton->needs_frame = 1; |
2566 | return 1; | |
2567 | } | |
2568 | ||
0acf8b65 JB |
2569 | /* struct dwarf_expr_context_funcs' "get_reg_value" callback: |
2570 | Reads from registers do require a frame. */ | |
2571 | ||
2572 | static struct value * | |
2573 | needs_frame_get_reg_value (void *baton, struct type *type, int regnum) | |
2574 | { | |
2575 | struct needs_frame_baton *nf_baton = baton; | |
2576 | ||
2577 | nf_baton->needs_frame = 1; | |
2578 | return value_zero (type, not_lval); | |
2579 | } | |
2580 | ||
4c2df51b DJ |
2581 | /* Reads from memory do not require a frame. */ |
2582 | static void | |
852483bc | 2583 | needs_frame_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
4c2df51b DJ |
2584 | { |
2585 | memset (buf, 0, len); | |
2586 | } | |
2587 | ||
2588 | /* Frame-relative accesses do require a frame. */ | |
2589 | static void | |
0d45f56e | 2590 | needs_frame_frame_base (void *baton, const gdb_byte **start, size_t * length) |
4c2df51b | 2591 | { |
852483bc | 2592 | static gdb_byte lit0 = DW_OP_lit0; |
4c2df51b DJ |
2593 | struct needs_frame_baton *nf_baton = baton; |
2594 | ||
2595 | *start = &lit0; | |
2596 | *length = 1; | |
2597 | ||
2598 | nf_baton->needs_frame = 1; | |
2599 | } | |
2600 | ||
e7802207 TT |
2601 | /* CFA accesses require a frame. */ |
2602 | ||
2603 | static CORE_ADDR | |
2604 | needs_frame_frame_cfa (void *baton) | |
2605 | { | |
2606 | struct needs_frame_baton *nf_baton = baton; | |
9a619af0 | 2607 | |
e7802207 TT |
2608 | nf_baton->needs_frame = 1; |
2609 | return 1; | |
2610 | } | |
2611 | ||
4c2df51b DJ |
2612 | /* Thread-local accesses do require a frame. */ |
2613 | static CORE_ADDR | |
2614 | needs_frame_tls_address (void *baton, CORE_ADDR offset) | |
2615 | { | |
2616 | struct needs_frame_baton *nf_baton = baton; | |
9a619af0 | 2617 | |
4c2df51b DJ |
2618 | nf_baton->needs_frame = 1; |
2619 | return 1; | |
2620 | } | |
2621 | ||
5c631832 JK |
2622 | /* Helper interface of per_cu_dwarf_call for dwarf2_loc_desc_needs_frame. */ |
2623 | ||
2624 | static void | |
b64f50a1 | 2625 | needs_frame_dwarf_call (struct dwarf_expr_context *ctx, cu_offset die_offset) |
5c631832 JK |
2626 | { |
2627 | struct needs_frame_baton *nf_baton = ctx->baton; | |
2628 | ||
37b50a69 | 2629 | per_cu_dwarf_call (ctx, die_offset, nf_baton->per_cu, |
9e8b7a03 | 2630 | ctx->funcs->get_frame_pc, ctx->baton); |
5c631832 JK |
2631 | } |
2632 | ||
8e3b41a9 JK |
2633 | /* DW_OP_GNU_entry_value accesses require a caller, therefore a frame. */ |
2634 | ||
2635 | static void | |
2636 | needs_dwarf_reg_entry_value (struct dwarf_expr_context *ctx, | |
24c5c679 JK |
2637 | enum call_site_parameter_kind kind, |
2638 | union call_site_parameter_u kind_u, int deref_size) | |
8e3b41a9 JK |
2639 | { |
2640 | struct needs_frame_baton *nf_baton = ctx->baton; | |
2641 | ||
2642 | nf_baton->needs_frame = 1; | |
1788b2d3 JK |
2643 | |
2644 | /* The expression may require some stub values on DWARF stack. */ | |
2645 | dwarf_expr_push_address (ctx, 0, 0); | |
8e3b41a9 JK |
2646 | } |
2647 | ||
3019eac3 DE |
2648 | /* DW_OP_GNU_addr_index doesn't require a frame. */ |
2649 | ||
2650 | static CORE_ADDR | |
2651 | needs_get_addr_index (void *baton, unsigned int index) | |
2652 | { | |
2653 | /* Nothing to do. */ | |
2654 | return 1; | |
2655 | } | |
2656 | ||
9e8b7a03 JK |
2657 | /* Virtual method table for dwarf2_loc_desc_needs_frame below. */ |
2658 | ||
2659 | static const struct dwarf_expr_context_funcs needs_frame_ctx_funcs = | |
2660 | { | |
b1370418 | 2661 | needs_frame_read_addr_from_reg, |
0acf8b65 | 2662 | needs_frame_get_reg_value, |
9e8b7a03 JK |
2663 | needs_frame_read_mem, |
2664 | needs_frame_frame_base, | |
2665 | needs_frame_frame_cfa, | |
2666 | needs_frame_frame_cfa, /* get_frame_pc */ | |
2667 | needs_frame_tls_address, | |
2668 | needs_frame_dwarf_call, | |
8e3b41a9 | 2669 | NULL, /* get_base_type */ |
3019eac3 DE |
2670 | needs_dwarf_reg_entry_value, |
2671 | needs_get_addr_index | |
9e8b7a03 JK |
2672 | }; |
2673 | ||
4c2df51b DJ |
2674 | /* Return non-zero iff the location expression at DATA (length SIZE) |
2675 | requires a frame to evaluate. */ | |
2676 | ||
2677 | static int | |
56eb65bd | 2678 | dwarf2_loc_desc_needs_frame (const gdb_byte *data, size_t size, |
ae0d2f24 | 2679 | struct dwarf2_per_cu_data *per_cu) |
4c2df51b DJ |
2680 | { |
2681 | struct needs_frame_baton baton; | |
2682 | struct dwarf_expr_context *ctx; | |
f630a401 | 2683 | int in_reg; |
4a227398 | 2684 | struct cleanup *old_chain; |
ac56253d | 2685 | struct objfile *objfile = dwarf2_per_cu_objfile (per_cu); |
4c2df51b DJ |
2686 | |
2687 | baton.needs_frame = 0; | |
17ea53c3 | 2688 | baton.per_cu = per_cu; |
4c2df51b DJ |
2689 | |
2690 | ctx = new_dwarf_expr_context (); | |
4a227398 | 2691 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
72fc29ff | 2692 | make_cleanup_value_free_to_mark (value_mark ()); |
4a227398 | 2693 | |
ac56253d | 2694 | ctx->gdbarch = get_objfile_arch (objfile); |
ae0d2f24 | 2695 | ctx->addr_size = dwarf2_per_cu_addr_size (per_cu); |
181cebd4 | 2696 | ctx->ref_addr_size = dwarf2_per_cu_ref_addr_size (per_cu); |
9aa1f1e3 | 2697 | ctx->offset = dwarf2_per_cu_text_offset (per_cu); |
4c2df51b | 2698 | ctx->baton = &baton; |
9e8b7a03 | 2699 | ctx->funcs = &needs_frame_ctx_funcs; |
4c2df51b DJ |
2700 | |
2701 | dwarf_expr_eval (ctx, data, size); | |
2702 | ||
cec03d70 | 2703 | in_reg = ctx->location == DWARF_VALUE_REGISTER; |
f630a401 | 2704 | |
87808bd6 JB |
2705 | if (ctx->num_pieces > 0) |
2706 | { | |
2707 | int i; | |
2708 | ||
2709 | /* If the location has several pieces, and any of them are in | |
2710 | registers, then we will need a frame to fetch them from. */ | |
2711 | for (i = 0; i < ctx->num_pieces; i++) | |
cec03d70 | 2712 | if (ctx->pieces[i].location == DWARF_VALUE_REGISTER) |
87808bd6 JB |
2713 | in_reg = 1; |
2714 | } | |
2715 | ||
4a227398 | 2716 | do_cleanups (old_chain); |
4c2df51b | 2717 | |
f630a401 | 2718 | return baton.needs_frame || in_reg; |
4c2df51b DJ |
2719 | } |
2720 | ||
3cf03773 TT |
2721 | /* A helper function that throws an unimplemented error mentioning a |
2722 | given DWARF operator. */ | |
2723 | ||
2724 | static void | |
2725 | unimplemented (unsigned int op) | |
0d53c4c4 | 2726 | { |
f39c6ffd | 2727 | const char *name = get_DW_OP_name (op); |
b1bfef65 TT |
2728 | |
2729 | if (name) | |
2730 | error (_("DWARF operator %s cannot be translated to an agent expression"), | |
2731 | name); | |
2732 | else | |
1ba1b353 TT |
2733 | error (_("Unknown DWARF operator 0x%02x cannot be translated " |
2734 | "to an agent expression"), | |
b1bfef65 | 2735 | op); |
3cf03773 | 2736 | } |
08922a10 | 2737 | |
3cf03773 TT |
2738 | /* A helper function to convert a DWARF register to an arch register. |
2739 | ARCH is the architecture. | |
2740 | DWARF_REG is the register. | |
2741 | This will throw an exception if the DWARF register cannot be | |
2742 | translated to an architecture register. */ | |
08922a10 | 2743 | |
3cf03773 TT |
2744 | static int |
2745 | translate_register (struct gdbarch *arch, int dwarf_reg) | |
2746 | { | |
2747 | int reg = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_reg); | |
2748 | if (reg == -1) | |
2749 | error (_("Unable to access DWARF register number %d"), dwarf_reg); | |
2750 | return reg; | |
2751 | } | |
08922a10 | 2752 | |
3cf03773 TT |
2753 | /* A helper function that emits an access to memory. ARCH is the |
2754 | target architecture. EXPR is the expression which we are building. | |
2755 | NBITS is the number of bits we want to read. This emits the | |
2756 | opcodes needed to read the memory and then extract the desired | |
2757 | bits. */ | |
08922a10 | 2758 | |
3cf03773 TT |
2759 | static void |
2760 | access_memory (struct gdbarch *arch, struct agent_expr *expr, ULONGEST nbits) | |
08922a10 | 2761 | { |
3cf03773 TT |
2762 | ULONGEST nbytes = (nbits + 7) / 8; |
2763 | ||
9df7235c | 2764 | gdb_assert (nbytes > 0 && nbytes <= sizeof (LONGEST)); |
3cf03773 | 2765 | |
92bc6a20 | 2766 | if (expr->tracing) |
3cf03773 TT |
2767 | ax_trace_quick (expr, nbytes); |
2768 | ||
2769 | if (nbits <= 8) | |
2770 | ax_simple (expr, aop_ref8); | |
2771 | else if (nbits <= 16) | |
2772 | ax_simple (expr, aop_ref16); | |
2773 | else if (nbits <= 32) | |
2774 | ax_simple (expr, aop_ref32); | |
2775 | else | |
2776 | ax_simple (expr, aop_ref64); | |
2777 | ||
2778 | /* If we read exactly the number of bytes we wanted, we're done. */ | |
2779 | if (8 * nbytes == nbits) | |
2780 | return; | |
2781 | ||
2782 | if (gdbarch_bits_big_endian (arch)) | |
0d53c4c4 | 2783 | { |
3cf03773 TT |
2784 | /* On a bits-big-endian machine, we want the high-order |
2785 | NBITS. */ | |
2786 | ax_const_l (expr, 8 * nbytes - nbits); | |
2787 | ax_simple (expr, aop_rsh_unsigned); | |
0d53c4c4 | 2788 | } |
3cf03773 | 2789 | else |
0d53c4c4 | 2790 | { |
3cf03773 TT |
2791 | /* On a bits-little-endian box, we want the low-order NBITS. */ |
2792 | ax_zero_ext (expr, nbits); | |
0d53c4c4 | 2793 | } |
3cf03773 | 2794 | } |
0936ad1d | 2795 | |
8cf6f0b1 TT |
2796 | /* A helper function to return the frame's PC. */ |
2797 | ||
2798 | static CORE_ADDR | |
2799 | get_ax_pc (void *baton) | |
2800 | { | |
2801 | struct agent_expr *expr = baton; | |
2802 | ||
2803 | return expr->scope; | |
2804 | } | |
2805 | ||
3cf03773 TT |
2806 | /* Compile a DWARF location expression to an agent expression. |
2807 | ||
2808 | EXPR is the agent expression we are building. | |
2809 | LOC is the agent value we modify. | |
2810 | ARCH is the architecture. | |
2811 | ADDR_SIZE is the size of addresses, in bytes. | |
2812 | OP_PTR is the start of the location expression. | |
2813 | OP_END is one past the last byte of the location expression. | |
2814 | ||
2815 | This will throw an exception for various kinds of errors -- for | |
2816 | example, if the expression cannot be compiled, or if the expression | |
2817 | is invalid. */ | |
0936ad1d | 2818 | |
9f6f94ff TT |
2819 | void |
2820 | dwarf2_compile_expr_to_ax (struct agent_expr *expr, struct axs_value *loc, | |
2821 | struct gdbarch *arch, unsigned int addr_size, | |
2822 | const gdb_byte *op_ptr, const gdb_byte *op_end, | |
2823 | struct dwarf2_per_cu_data *per_cu) | |
3cf03773 TT |
2824 | { |
2825 | struct cleanup *cleanups; | |
2826 | int i, *offsets; | |
2827 | VEC(int) *dw_labels = NULL, *patches = NULL; | |
2828 | const gdb_byte * const base = op_ptr; | |
2829 | const gdb_byte *previous_piece = op_ptr; | |
2830 | enum bfd_endian byte_order = gdbarch_byte_order (arch); | |
2831 | ULONGEST bits_collected = 0; | |
2832 | unsigned int addr_size_bits = 8 * addr_size; | |
2833 | int bits_big_endian = gdbarch_bits_big_endian (arch); | |
0936ad1d | 2834 | |
3cf03773 TT |
2835 | offsets = xmalloc ((op_end - op_ptr) * sizeof (int)); |
2836 | cleanups = make_cleanup (xfree, offsets); | |
0936ad1d | 2837 | |
3cf03773 TT |
2838 | for (i = 0; i < op_end - op_ptr; ++i) |
2839 | offsets[i] = -1; | |
0936ad1d | 2840 | |
3cf03773 TT |
2841 | make_cleanup (VEC_cleanup (int), &dw_labels); |
2842 | make_cleanup (VEC_cleanup (int), &patches); | |
0936ad1d | 2843 | |
3cf03773 TT |
2844 | /* By default we are making an address. */ |
2845 | loc->kind = axs_lvalue_memory; | |
0d45f56e | 2846 | |
3cf03773 TT |
2847 | while (op_ptr < op_end) |
2848 | { | |
2849 | enum dwarf_location_atom op = *op_ptr; | |
9fccedf7 DE |
2850 | uint64_t uoffset, reg; |
2851 | int64_t offset; | |
3cf03773 TT |
2852 | int i; |
2853 | ||
2854 | offsets[op_ptr - base] = expr->len; | |
2855 | ++op_ptr; | |
2856 | ||
2857 | /* Our basic approach to code generation is to map DWARF | |
2858 | operations directly to AX operations. However, there are | |
2859 | some differences. | |
2860 | ||
2861 | First, DWARF works on address-sized units, but AX always uses | |
2862 | LONGEST. For most operations we simply ignore this | |
2863 | difference; instead we generate sign extensions as needed | |
2864 | before division and comparison operations. It would be nice | |
2865 | to omit the sign extensions, but there is no way to determine | |
2866 | the size of the target's LONGEST. (This code uses the size | |
2867 | of the host LONGEST in some cases -- that is a bug but it is | |
2868 | difficult to fix.) | |
2869 | ||
2870 | Second, some DWARF operations cannot be translated to AX. | |
2871 | For these we simply fail. See | |
2872 | http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */ | |
2873 | switch (op) | |
0936ad1d | 2874 | { |
3cf03773 TT |
2875 | case DW_OP_lit0: |
2876 | case DW_OP_lit1: | |
2877 | case DW_OP_lit2: | |
2878 | case DW_OP_lit3: | |
2879 | case DW_OP_lit4: | |
2880 | case DW_OP_lit5: | |
2881 | case DW_OP_lit6: | |
2882 | case DW_OP_lit7: | |
2883 | case DW_OP_lit8: | |
2884 | case DW_OP_lit9: | |
2885 | case DW_OP_lit10: | |
2886 | case DW_OP_lit11: | |
2887 | case DW_OP_lit12: | |
2888 | case DW_OP_lit13: | |
2889 | case DW_OP_lit14: | |
2890 | case DW_OP_lit15: | |
2891 | case DW_OP_lit16: | |
2892 | case DW_OP_lit17: | |
2893 | case DW_OP_lit18: | |
2894 | case DW_OP_lit19: | |
2895 | case DW_OP_lit20: | |
2896 | case DW_OP_lit21: | |
2897 | case DW_OP_lit22: | |
2898 | case DW_OP_lit23: | |
2899 | case DW_OP_lit24: | |
2900 | case DW_OP_lit25: | |
2901 | case DW_OP_lit26: | |
2902 | case DW_OP_lit27: | |
2903 | case DW_OP_lit28: | |
2904 | case DW_OP_lit29: | |
2905 | case DW_OP_lit30: | |
2906 | case DW_OP_lit31: | |
2907 | ax_const_l (expr, op - DW_OP_lit0); | |
2908 | break; | |
0d53c4c4 | 2909 | |
3cf03773 | 2910 | case DW_OP_addr: |
ac56253d | 2911 | uoffset = extract_unsigned_integer (op_ptr, addr_size, byte_order); |
3cf03773 | 2912 | op_ptr += addr_size; |
ac56253d TT |
2913 | /* Some versions of GCC emit DW_OP_addr before |
2914 | DW_OP_GNU_push_tls_address. In this case the value is an | |
2915 | index, not an address. We don't support things like | |
2916 | branching between the address and the TLS op. */ | |
2917 | if (op_ptr >= op_end || *op_ptr != DW_OP_GNU_push_tls_address) | |
9aa1f1e3 | 2918 | uoffset += dwarf2_per_cu_text_offset (per_cu); |
ac56253d | 2919 | ax_const_l (expr, uoffset); |
3cf03773 | 2920 | break; |
4c2df51b | 2921 | |
3cf03773 TT |
2922 | case DW_OP_const1u: |
2923 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 1, byte_order)); | |
2924 | op_ptr += 1; | |
2925 | break; | |
2926 | case DW_OP_const1s: | |
2927 | ax_const_l (expr, extract_signed_integer (op_ptr, 1, byte_order)); | |
2928 | op_ptr += 1; | |
2929 | break; | |
2930 | case DW_OP_const2u: | |
2931 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 2, byte_order)); | |
2932 | op_ptr += 2; | |
2933 | break; | |
2934 | case DW_OP_const2s: | |
2935 | ax_const_l (expr, extract_signed_integer (op_ptr, 2, byte_order)); | |
2936 | op_ptr += 2; | |
2937 | break; | |
2938 | case DW_OP_const4u: | |
2939 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 4, byte_order)); | |
2940 | op_ptr += 4; | |
2941 | break; | |
2942 | case DW_OP_const4s: | |
2943 | ax_const_l (expr, extract_signed_integer (op_ptr, 4, byte_order)); | |
2944 | op_ptr += 4; | |
2945 | break; | |
2946 | case DW_OP_const8u: | |
2947 | ax_const_l (expr, extract_unsigned_integer (op_ptr, 8, byte_order)); | |
2948 | op_ptr += 8; | |
2949 | break; | |
2950 | case DW_OP_const8s: | |
2951 | ax_const_l (expr, extract_signed_integer (op_ptr, 8, byte_order)); | |
2952 | op_ptr += 8; | |
2953 | break; | |
2954 | case DW_OP_constu: | |
f664829e | 2955 | op_ptr = safe_read_uleb128 (op_ptr, op_end, &uoffset); |
3cf03773 TT |
2956 | ax_const_l (expr, uoffset); |
2957 | break; | |
2958 | case DW_OP_consts: | |
f664829e | 2959 | op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset); |
3cf03773 TT |
2960 | ax_const_l (expr, offset); |
2961 | break; | |
9c238357 | 2962 | |
3cf03773 TT |
2963 | case DW_OP_reg0: |
2964 | case DW_OP_reg1: | |
2965 | case DW_OP_reg2: | |
2966 | case DW_OP_reg3: | |
2967 | case DW_OP_reg4: | |
2968 | case DW_OP_reg5: | |
2969 | case DW_OP_reg6: | |
2970 | case DW_OP_reg7: | |
2971 | case DW_OP_reg8: | |
2972 | case DW_OP_reg9: | |
2973 | case DW_OP_reg10: | |
2974 | case DW_OP_reg11: | |
2975 | case DW_OP_reg12: | |
2976 | case DW_OP_reg13: | |
2977 | case DW_OP_reg14: | |
2978 | case DW_OP_reg15: | |
2979 | case DW_OP_reg16: | |
2980 | case DW_OP_reg17: | |
2981 | case DW_OP_reg18: | |
2982 | case DW_OP_reg19: | |
2983 | case DW_OP_reg20: | |
2984 | case DW_OP_reg21: | |
2985 | case DW_OP_reg22: | |
2986 | case DW_OP_reg23: | |
2987 | case DW_OP_reg24: | |
2988 | case DW_OP_reg25: | |
2989 | case DW_OP_reg26: | |
2990 | case DW_OP_reg27: | |
2991 | case DW_OP_reg28: | |
2992 | case DW_OP_reg29: | |
2993 | case DW_OP_reg30: | |
2994 | case DW_OP_reg31: | |
2995 | dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx"); | |
2996 | loc->u.reg = translate_register (arch, op - DW_OP_reg0); | |
2997 | loc->kind = axs_lvalue_register; | |
2998 | break; | |
9c238357 | 2999 | |
3cf03773 | 3000 | case DW_OP_regx: |
f664829e | 3001 | op_ptr = safe_read_uleb128 (op_ptr, op_end, ®); |
3cf03773 TT |
3002 | dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_regx"); |
3003 | loc->u.reg = translate_register (arch, reg); | |
3004 | loc->kind = axs_lvalue_register; | |
3005 | break; | |
08922a10 | 3006 | |
3cf03773 TT |
3007 | case DW_OP_implicit_value: |
3008 | { | |
9fccedf7 | 3009 | uint64_t len; |
3cf03773 | 3010 | |
f664829e | 3011 | op_ptr = safe_read_uleb128 (op_ptr, op_end, &len); |
3cf03773 TT |
3012 | if (op_ptr + len > op_end) |
3013 | error (_("DW_OP_implicit_value: too few bytes available.")); | |
3014 | if (len > sizeof (ULONGEST)) | |
3015 | error (_("Cannot translate DW_OP_implicit_value of %d bytes"), | |
3016 | (int) len); | |
3017 | ||
3018 | ax_const_l (expr, extract_unsigned_integer (op_ptr, len, | |
3019 | byte_order)); | |
3020 | op_ptr += len; | |
3021 | dwarf_expr_require_composition (op_ptr, op_end, | |
3022 | "DW_OP_implicit_value"); | |
3023 | ||
3024 | loc->kind = axs_rvalue; | |
3025 | } | |
3026 | break; | |
08922a10 | 3027 | |
3cf03773 TT |
3028 | case DW_OP_stack_value: |
3029 | dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value"); | |
3030 | loc->kind = axs_rvalue; | |
3031 | break; | |
08922a10 | 3032 | |
3cf03773 TT |
3033 | case DW_OP_breg0: |
3034 | case DW_OP_breg1: | |
3035 | case DW_OP_breg2: | |
3036 | case DW_OP_breg3: | |
3037 | case DW_OP_breg4: | |
3038 | case DW_OP_breg5: | |
3039 | case DW_OP_breg6: | |
3040 | case DW_OP_breg7: | |
3041 | case DW_OP_breg8: | |
3042 | case DW_OP_breg9: | |
3043 | case DW_OP_breg10: | |
3044 | case DW_OP_breg11: | |
3045 | case DW_OP_breg12: | |
3046 | case DW_OP_breg13: | |
3047 | case DW_OP_breg14: | |
3048 | case DW_OP_breg15: | |
3049 | case DW_OP_breg16: | |
3050 | case DW_OP_breg17: | |
3051 | case DW_OP_breg18: | |
3052 | case DW_OP_breg19: | |
3053 | case DW_OP_breg20: | |
3054 | case DW_OP_breg21: | |
3055 | case DW_OP_breg22: | |
3056 | case DW_OP_breg23: | |
3057 | case DW_OP_breg24: | |
3058 | case DW_OP_breg25: | |
3059 | case DW_OP_breg26: | |
3060 | case DW_OP_breg27: | |
3061 | case DW_OP_breg28: | |
3062 | case DW_OP_breg29: | |
3063 | case DW_OP_breg30: | |
3064 | case DW_OP_breg31: | |
f664829e | 3065 | op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset); |
3cf03773 TT |
3066 | i = translate_register (arch, op - DW_OP_breg0); |
3067 | ax_reg (expr, i); | |
3068 | if (offset != 0) | |
3069 | { | |
3070 | ax_const_l (expr, offset); | |
3071 | ax_simple (expr, aop_add); | |
3072 | } | |
3073 | break; | |
3074 | case DW_OP_bregx: | |
3075 | { | |
f664829e DE |
3076 | op_ptr = safe_read_uleb128 (op_ptr, op_end, ®); |
3077 | op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset); | |
3cf03773 TT |
3078 | i = translate_register (arch, reg); |
3079 | ax_reg (expr, i); | |
3080 | if (offset != 0) | |
3081 | { | |
3082 | ax_const_l (expr, offset); | |
3083 | ax_simple (expr, aop_add); | |
3084 | } | |
3085 | } | |
3086 | break; | |
3087 | case DW_OP_fbreg: | |
3088 | { | |
3089 | const gdb_byte *datastart; | |
3090 | size_t datalen; | |
3cf03773 TT |
3091 | struct block *b; |
3092 | struct symbol *framefunc; | |
08922a10 | 3093 | |
3cf03773 TT |
3094 | b = block_for_pc (expr->scope); |
3095 | ||
3096 | if (!b) | |
3097 | error (_("No block found for address")); | |
3098 | ||
3099 | framefunc = block_linkage_function (b); | |
3100 | ||
3101 | if (!framefunc) | |
3102 | error (_("No function found for block")); | |
3103 | ||
3104 | dwarf_expr_frame_base_1 (framefunc, expr->scope, | |
3105 | &datastart, &datalen); | |
3106 | ||
f664829e | 3107 | op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset); |
9f6f94ff TT |
3108 | dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size, datastart, |
3109 | datastart + datalen, per_cu); | |
d84cf7eb TT |
3110 | if (loc->kind == axs_lvalue_register) |
3111 | require_rvalue (expr, loc); | |
3cf03773 TT |
3112 | |
3113 | if (offset != 0) | |
3114 | { | |
3115 | ax_const_l (expr, offset); | |
3116 | ax_simple (expr, aop_add); | |
3117 | } | |
3118 | ||
3119 | loc->kind = axs_lvalue_memory; | |
3120 | } | |
08922a10 | 3121 | break; |
08922a10 | 3122 | |
3cf03773 TT |
3123 | case DW_OP_dup: |
3124 | ax_simple (expr, aop_dup); | |
3125 | break; | |
08922a10 | 3126 | |
3cf03773 TT |
3127 | case DW_OP_drop: |
3128 | ax_simple (expr, aop_pop); | |
3129 | break; | |
08922a10 | 3130 | |
3cf03773 TT |
3131 | case DW_OP_pick: |
3132 | offset = *op_ptr++; | |
c7f96d2b | 3133 | ax_pick (expr, offset); |
3cf03773 TT |
3134 | break; |
3135 | ||
3136 | case DW_OP_swap: | |
3137 | ax_simple (expr, aop_swap); | |
3138 | break; | |
08922a10 | 3139 | |
3cf03773 | 3140 | case DW_OP_over: |
c7f96d2b | 3141 | ax_pick (expr, 1); |
3cf03773 | 3142 | break; |
08922a10 | 3143 | |
3cf03773 | 3144 | case DW_OP_rot: |
c7f96d2b | 3145 | ax_simple (expr, aop_rot); |
3cf03773 | 3146 | break; |
08922a10 | 3147 | |
3cf03773 TT |
3148 | case DW_OP_deref: |
3149 | case DW_OP_deref_size: | |
3150 | { | |
3151 | int size; | |
08922a10 | 3152 | |
3cf03773 TT |
3153 | if (op == DW_OP_deref_size) |
3154 | size = *op_ptr++; | |
3155 | else | |
3156 | size = addr_size; | |
3157 | ||
9df7235c | 3158 | if (size != 1 && size != 2 && size != 4 && size != 8) |
f3cec7e6 HZ |
3159 | error (_("Unsupported size %d in %s"), |
3160 | size, get_DW_OP_name (op)); | |
9df7235c | 3161 | access_memory (arch, expr, size * TARGET_CHAR_BIT); |
3cf03773 TT |
3162 | } |
3163 | break; | |
3164 | ||
3165 | case DW_OP_abs: | |
3166 | /* Sign extend the operand. */ | |
3167 | ax_ext (expr, addr_size_bits); | |
3168 | ax_simple (expr, aop_dup); | |
3169 | ax_const_l (expr, 0); | |
3170 | ax_simple (expr, aop_less_signed); | |
3171 | ax_simple (expr, aop_log_not); | |
3172 | i = ax_goto (expr, aop_if_goto); | |
3173 | /* We have to emit 0 - X. */ | |
3174 | ax_const_l (expr, 0); | |
3175 | ax_simple (expr, aop_swap); | |
3176 | ax_simple (expr, aop_sub); | |
3177 | ax_label (expr, i, expr->len); | |
3178 | break; | |
3179 | ||
3180 | case DW_OP_neg: | |
3181 | /* No need to sign extend here. */ | |
3182 | ax_const_l (expr, 0); | |
3183 | ax_simple (expr, aop_swap); | |
3184 | ax_simple (expr, aop_sub); | |
3185 | break; | |
3186 | ||
3187 | case DW_OP_not: | |
3188 | /* Sign extend the operand. */ | |
3189 | ax_ext (expr, addr_size_bits); | |
3190 | ax_simple (expr, aop_bit_not); | |
3191 | break; | |
3192 | ||
3193 | case DW_OP_plus_uconst: | |
f664829e | 3194 | op_ptr = safe_read_uleb128 (op_ptr, op_end, ®); |
3cf03773 TT |
3195 | /* It would be really weird to emit `DW_OP_plus_uconst 0', |
3196 | but we micro-optimize anyhow. */ | |
3197 | if (reg != 0) | |
3198 | { | |
3199 | ax_const_l (expr, reg); | |
3200 | ax_simple (expr, aop_add); | |
3201 | } | |
3202 | break; | |
3203 | ||
3204 | case DW_OP_and: | |
3205 | ax_simple (expr, aop_bit_and); | |
3206 | break; | |
3207 | ||
3208 | case DW_OP_div: | |
3209 | /* Sign extend the operands. */ | |
3210 | ax_ext (expr, addr_size_bits); | |
3211 | ax_simple (expr, aop_swap); | |
3212 | ax_ext (expr, addr_size_bits); | |
3213 | ax_simple (expr, aop_swap); | |
3214 | ax_simple (expr, aop_div_signed); | |
08922a10 SS |
3215 | break; |
3216 | ||
3cf03773 TT |
3217 | case DW_OP_minus: |
3218 | ax_simple (expr, aop_sub); | |
3219 | break; | |
3220 | ||
3221 | case DW_OP_mod: | |
3222 | ax_simple (expr, aop_rem_unsigned); | |
3223 | break; | |
3224 | ||
3225 | case DW_OP_mul: | |
3226 | ax_simple (expr, aop_mul); | |
3227 | break; | |
3228 | ||
3229 | case DW_OP_or: | |
3230 | ax_simple (expr, aop_bit_or); | |
3231 | break; | |
3232 | ||
3233 | case DW_OP_plus: | |
3234 | ax_simple (expr, aop_add); | |
3235 | break; | |
3236 | ||
3237 | case DW_OP_shl: | |
3238 | ax_simple (expr, aop_lsh); | |
3239 | break; | |
3240 | ||
3241 | case DW_OP_shr: | |
3242 | ax_simple (expr, aop_rsh_unsigned); | |
3243 | break; | |
3244 | ||
3245 | case DW_OP_shra: | |
3246 | ax_simple (expr, aop_rsh_signed); | |
3247 | break; | |
3248 | ||
3249 | case DW_OP_xor: | |
3250 | ax_simple (expr, aop_bit_xor); | |
3251 | break; | |
3252 | ||
3253 | case DW_OP_le: | |
3254 | /* Sign extend the operands. */ | |
3255 | ax_ext (expr, addr_size_bits); | |
3256 | ax_simple (expr, aop_swap); | |
3257 | ax_ext (expr, addr_size_bits); | |
3258 | /* Note no swap here: A <= B is !(B < A). */ | |
3259 | ax_simple (expr, aop_less_signed); | |
3260 | ax_simple (expr, aop_log_not); | |
3261 | break; | |
3262 | ||
3263 | case DW_OP_ge: | |
3264 | /* Sign extend the operands. */ | |
3265 | ax_ext (expr, addr_size_bits); | |
3266 | ax_simple (expr, aop_swap); | |
3267 | ax_ext (expr, addr_size_bits); | |
3268 | ax_simple (expr, aop_swap); | |
3269 | /* A >= B is !(A < B). */ | |
3270 | ax_simple (expr, aop_less_signed); | |
3271 | ax_simple (expr, aop_log_not); | |
3272 | break; | |
3273 | ||
3274 | case DW_OP_eq: | |
3275 | /* Sign extend the operands. */ | |
3276 | ax_ext (expr, addr_size_bits); | |
3277 | ax_simple (expr, aop_swap); | |
3278 | ax_ext (expr, addr_size_bits); | |
3279 | /* No need for a second swap here. */ | |
3280 | ax_simple (expr, aop_equal); | |
3281 | break; | |
3282 | ||
3283 | case DW_OP_lt: | |
3284 | /* Sign extend the operands. */ | |
3285 | ax_ext (expr, addr_size_bits); | |
3286 | ax_simple (expr, aop_swap); | |
3287 | ax_ext (expr, addr_size_bits); | |
3288 | ax_simple (expr, aop_swap); | |
3289 | ax_simple (expr, aop_less_signed); | |
3290 | break; | |
3291 | ||
3292 | case DW_OP_gt: | |
3293 | /* Sign extend the operands. */ | |
3294 | ax_ext (expr, addr_size_bits); | |
3295 | ax_simple (expr, aop_swap); | |
3296 | ax_ext (expr, addr_size_bits); | |
3297 | /* Note no swap here: A > B is B < A. */ | |
3298 | ax_simple (expr, aop_less_signed); | |
3299 | break; | |
3300 | ||
3301 | case DW_OP_ne: | |
3302 | /* Sign extend the operands. */ | |
3303 | ax_ext (expr, addr_size_bits); | |
3304 | ax_simple (expr, aop_swap); | |
3305 | ax_ext (expr, addr_size_bits); | |
3306 | /* No need for a swap here. */ | |
3307 | ax_simple (expr, aop_equal); | |
3308 | ax_simple (expr, aop_log_not); | |
3309 | break; | |
3310 | ||
3311 | case DW_OP_call_frame_cfa: | |
9f6f94ff TT |
3312 | dwarf2_compile_cfa_to_ax (expr, loc, arch, expr->scope, per_cu); |
3313 | loc->kind = axs_lvalue_memory; | |
3cf03773 TT |
3314 | break; |
3315 | ||
3316 | case DW_OP_GNU_push_tls_address: | |
3317 | unimplemented (op); | |
3318 | break; | |
3319 | ||
3320 | case DW_OP_skip: | |
3321 | offset = extract_signed_integer (op_ptr, 2, byte_order); | |
3322 | op_ptr += 2; | |
3323 | i = ax_goto (expr, aop_goto); | |
3324 | VEC_safe_push (int, dw_labels, op_ptr + offset - base); | |
3325 | VEC_safe_push (int, patches, i); | |
3326 | break; | |
3327 | ||
3328 | case DW_OP_bra: | |
3329 | offset = extract_signed_integer (op_ptr, 2, byte_order); | |
3330 | op_ptr += 2; | |
3331 | /* Zero extend the operand. */ | |
3332 | ax_zero_ext (expr, addr_size_bits); | |
3333 | i = ax_goto (expr, aop_if_goto); | |
3334 | VEC_safe_push (int, dw_labels, op_ptr + offset - base); | |
3335 | VEC_safe_push (int, patches, i); | |
3336 | break; | |
3337 | ||
3338 | case DW_OP_nop: | |
3339 | break; | |
3340 | ||
3341 | case DW_OP_piece: | |
3342 | case DW_OP_bit_piece: | |
08922a10 | 3343 | { |
9fccedf7 | 3344 | uint64_t size, offset; |
3cf03773 TT |
3345 | |
3346 | if (op_ptr - 1 == previous_piece) | |
3347 | error (_("Cannot translate empty pieces to agent expressions")); | |
3348 | previous_piece = op_ptr - 1; | |
3349 | ||
f664829e | 3350 | op_ptr = safe_read_uleb128 (op_ptr, op_end, &size); |
3cf03773 TT |
3351 | if (op == DW_OP_piece) |
3352 | { | |
3353 | size *= 8; | |
3354 | offset = 0; | |
3355 | } | |
3356 | else | |
f664829e | 3357 | op_ptr = safe_read_uleb128 (op_ptr, op_end, &offset); |
08922a10 | 3358 | |
3cf03773 TT |
3359 | if (bits_collected + size > 8 * sizeof (LONGEST)) |
3360 | error (_("Expression pieces exceed word size")); | |
3361 | ||
3362 | /* Access the bits. */ | |
3363 | switch (loc->kind) | |
3364 | { | |
3365 | case axs_lvalue_register: | |
3366 | ax_reg (expr, loc->u.reg); | |
3367 | break; | |
3368 | ||
3369 | case axs_lvalue_memory: | |
3370 | /* Offset the pointer, if needed. */ | |
3371 | if (offset > 8) | |
3372 | { | |
3373 | ax_const_l (expr, offset / 8); | |
3374 | ax_simple (expr, aop_add); | |
3375 | offset %= 8; | |
3376 | } | |
3377 | access_memory (arch, expr, size); | |
3378 | break; | |
3379 | } | |
3380 | ||
3381 | /* For a bits-big-endian target, shift up what we already | |
3382 | have. For a bits-little-endian target, shift up the | |
3383 | new data. Note that there is a potential bug here if | |
3384 | the DWARF expression leaves multiple values on the | |
3385 | stack. */ | |
3386 | if (bits_collected > 0) | |
3387 | { | |
3388 | if (bits_big_endian) | |
3389 | { | |
3390 | ax_simple (expr, aop_swap); | |
3391 | ax_const_l (expr, size); | |
3392 | ax_simple (expr, aop_lsh); | |
3393 | /* We don't need a second swap here, because | |
3394 | aop_bit_or is symmetric. */ | |
3395 | } | |
3396 | else | |
3397 | { | |
3398 | ax_const_l (expr, size); | |
3399 | ax_simple (expr, aop_lsh); | |
3400 | } | |
3401 | ax_simple (expr, aop_bit_or); | |
3402 | } | |
3403 | ||
3404 | bits_collected += size; | |
3405 | loc->kind = axs_rvalue; | |
08922a10 SS |
3406 | } |
3407 | break; | |
08922a10 | 3408 | |
3cf03773 TT |
3409 | case DW_OP_GNU_uninit: |
3410 | unimplemented (op); | |
3411 | ||
3412 | case DW_OP_call2: | |
3413 | case DW_OP_call4: | |
3414 | { | |
3415 | struct dwarf2_locexpr_baton block; | |
3416 | int size = (op == DW_OP_call2 ? 2 : 4); | |
b64f50a1 | 3417 | cu_offset offset; |
3cf03773 TT |
3418 | |
3419 | uoffset = extract_unsigned_integer (op_ptr, size, byte_order); | |
3420 | op_ptr += size; | |
3421 | ||
b64f50a1 | 3422 | offset.cu_off = uoffset; |
8b9737bf TT |
3423 | block = dwarf2_fetch_die_loc_cu_off (offset, per_cu, |
3424 | get_ax_pc, expr); | |
3cf03773 TT |
3425 | |
3426 | /* DW_OP_call_ref is currently not supported. */ | |
3427 | gdb_assert (block.per_cu == per_cu); | |
3428 | ||
9f6f94ff TT |
3429 | dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size, |
3430 | block.data, block.data + block.size, | |
3431 | per_cu); | |
3cf03773 TT |
3432 | } |
3433 | break; | |
3434 | ||
3435 | case DW_OP_call_ref: | |
3436 | unimplemented (op); | |
3437 | ||
3438 | default: | |
b1bfef65 | 3439 | unimplemented (op); |
08922a10 | 3440 | } |
08922a10 | 3441 | } |
3cf03773 TT |
3442 | |
3443 | /* Patch all the branches we emitted. */ | |
3444 | for (i = 0; i < VEC_length (int, patches); ++i) | |
3445 | { | |
3446 | int targ = offsets[VEC_index (int, dw_labels, i)]; | |
3447 | if (targ == -1) | |
3448 | internal_error (__FILE__, __LINE__, _("invalid label")); | |
3449 | ax_label (expr, VEC_index (int, patches, i), targ); | |
3450 | } | |
3451 | ||
3452 | do_cleanups (cleanups); | |
08922a10 SS |
3453 | } |
3454 | ||
4c2df51b DJ |
3455 | \f |
3456 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression | |
3457 | evaluator to calculate the location. */ | |
3458 | static struct value * | |
3459 | locexpr_read_variable (struct symbol *symbol, struct frame_info *frame) | |
3460 | { | |
3461 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
3462 | struct value *val; | |
9a619af0 | 3463 | |
a2d33775 JK |
3464 | val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, dlbaton->data, |
3465 | dlbaton->size, dlbaton->per_cu); | |
4c2df51b DJ |
3466 | |
3467 | return val; | |
3468 | } | |
3469 | ||
e18b2753 JK |
3470 | /* Return the value of SYMBOL in FRAME at (callee) FRAME's function |
3471 | entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR | |
3472 | will be thrown. */ | |
3473 | ||
3474 | static struct value * | |
3475 | locexpr_read_variable_at_entry (struct symbol *symbol, struct frame_info *frame) | |
3476 | { | |
3477 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
3478 | ||
3479 | return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol), frame, dlbaton->data, | |
3480 | dlbaton->size); | |
3481 | } | |
3482 | ||
4c2df51b DJ |
3483 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ |
3484 | static int | |
3485 | locexpr_read_needs_frame (struct symbol *symbol) | |
3486 | { | |
3487 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
9a619af0 | 3488 | |
ae0d2f24 UW |
3489 | return dwarf2_loc_desc_needs_frame (dlbaton->data, dlbaton->size, |
3490 | dlbaton->per_cu); | |
4c2df51b DJ |
3491 | } |
3492 | ||
9eae7c52 TT |
3493 | /* Return true if DATA points to the end of a piece. END is one past |
3494 | the last byte in the expression. */ | |
3495 | ||
3496 | static int | |
3497 | piece_end_p (const gdb_byte *data, const gdb_byte *end) | |
3498 | { | |
3499 | return data == end || data[0] == DW_OP_piece || data[0] == DW_OP_bit_piece; | |
3500 | } | |
3501 | ||
5e44ecb3 TT |
3502 | /* Helper for locexpr_describe_location_piece that finds the name of a |
3503 | DWARF register. */ | |
3504 | ||
3505 | static const char * | |
3506 | locexpr_regname (struct gdbarch *gdbarch, int dwarf_regnum) | |
3507 | { | |
3508 | int regnum; | |
3509 | ||
3510 | regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum); | |
3511 | return gdbarch_register_name (gdbarch, regnum); | |
3512 | } | |
3513 | ||
9eae7c52 TT |
3514 | /* Nicely describe a single piece of a location, returning an updated |
3515 | position in the bytecode sequence. This function cannot recognize | |
3516 | all locations; if a location is not recognized, it simply returns | |
f664829e DE |
3517 | DATA. If there is an error during reading, e.g. we run off the end |
3518 | of the buffer, an error is thrown. */ | |
08922a10 | 3519 | |
0d45f56e | 3520 | static const gdb_byte * |
08922a10 SS |
3521 | locexpr_describe_location_piece (struct symbol *symbol, struct ui_file *stream, |
3522 | CORE_ADDR addr, struct objfile *objfile, | |
49f6c839 | 3523 | struct dwarf2_per_cu_data *per_cu, |
9eae7c52 | 3524 | const gdb_byte *data, const gdb_byte *end, |
0d45f56e | 3525 | unsigned int addr_size) |
4c2df51b | 3526 | { |
08922a10 | 3527 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
49f6c839 | 3528 | size_t leb128_size; |
08922a10 SS |
3529 | |
3530 | if (data[0] >= DW_OP_reg0 && data[0] <= DW_OP_reg31) | |
3531 | { | |
08922a10 | 3532 | fprintf_filtered (stream, _("a variable in $%s"), |
5e44ecb3 | 3533 | locexpr_regname (gdbarch, data[0] - DW_OP_reg0)); |
08922a10 SS |
3534 | data += 1; |
3535 | } | |
3536 | else if (data[0] == DW_OP_regx) | |
3537 | { | |
9fccedf7 | 3538 | uint64_t reg; |
4c2df51b | 3539 | |
f664829e | 3540 | data = safe_read_uleb128 (data + 1, end, ®); |
08922a10 | 3541 | fprintf_filtered (stream, _("a variable in $%s"), |
5e44ecb3 | 3542 | locexpr_regname (gdbarch, reg)); |
08922a10 SS |
3543 | } |
3544 | else if (data[0] == DW_OP_fbreg) | |
4c2df51b | 3545 | { |
08922a10 SS |
3546 | struct block *b; |
3547 | struct symbol *framefunc; | |
3548 | int frame_reg = 0; | |
9fccedf7 | 3549 | int64_t frame_offset; |
7155d578 | 3550 | const gdb_byte *base_data, *new_data, *save_data = data; |
08922a10 | 3551 | size_t base_size; |
9fccedf7 | 3552 | int64_t base_offset = 0; |
08922a10 | 3553 | |
f664829e | 3554 | new_data = safe_read_sleb128 (data + 1, end, &frame_offset); |
9eae7c52 TT |
3555 | if (!piece_end_p (new_data, end)) |
3556 | return data; | |
3557 | data = new_data; | |
3558 | ||
08922a10 SS |
3559 | b = block_for_pc (addr); |
3560 | ||
3561 | if (!b) | |
3562 | error (_("No block found for address for symbol \"%s\"."), | |
3563 | SYMBOL_PRINT_NAME (symbol)); | |
3564 | ||
3565 | framefunc = block_linkage_function (b); | |
3566 | ||
3567 | if (!framefunc) | |
3568 | error (_("No function found for block for symbol \"%s\"."), | |
3569 | SYMBOL_PRINT_NAME (symbol)); | |
3570 | ||
3571 | dwarf_expr_frame_base_1 (framefunc, addr, &base_data, &base_size); | |
3572 | ||
3573 | if (base_data[0] >= DW_OP_breg0 && base_data[0] <= DW_OP_breg31) | |
3574 | { | |
0d45f56e | 3575 | const gdb_byte *buf_end; |
08922a10 SS |
3576 | |
3577 | frame_reg = base_data[0] - DW_OP_breg0; | |
f664829e DE |
3578 | buf_end = safe_read_sleb128 (base_data + 1, base_data + base_size, |
3579 | &base_offset); | |
08922a10 | 3580 | if (buf_end != base_data + base_size) |
3e43a32a MS |
3581 | error (_("Unexpected opcode after " |
3582 | "DW_OP_breg%u for symbol \"%s\"."), | |
08922a10 SS |
3583 | frame_reg, SYMBOL_PRINT_NAME (symbol)); |
3584 | } | |
3585 | else if (base_data[0] >= DW_OP_reg0 && base_data[0] <= DW_OP_reg31) | |
3586 | { | |
3587 | /* The frame base is just the register, with no offset. */ | |
3588 | frame_reg = base_data[0] - DW_OP_reg0; | |
3589 | base_offset = 0; | |
3590 | } | |
3591 | else | |
3592 | { | |
3593 | /* We don't know what to do with the frame base expression, | |
3594 | so we can't trace this variable; give up. */ | |
7155d578 | 3595 | return save_data; |
08922a10 SS |
3596 | } |
3597 | ||
3e43a32a MS |
3598 | fprintf_filtered (stream, |
3599 | _("a variable at frame base reg $%s offset %s+%s"), | |
5e44ecb3 | 3600 | locexpr_regname (gdbarch, frame_reg), |
08922a10 SS |
3601 | plongest (base_offset), plongest (frame_offset)); |
3602 | } | |
9eae7c52 TT |
3603 | else if (data[0] >= DW_OP_breg0 && data[0] <= DW_OP_breg31 |
3604 | && piece_end_p (data, end)) | |
08922a10 | 3605 | { |
9fccedf7 | 3606 | int64_t offset; |
08922a10 | 3607 | |
f664829e | 3608 | data = safe_read_sleb128 (data + 1, end, &offset); |
08922a10 | 3609 | |
4c2df51b | 3610 | fprintf_filtered (stream, |
08922a10 SS |
3611 | _("a variable at offset %s from base reg $%s"), |
3612 | plongest (offset), | |
5e44ecb3 | 3613 | locexpr_regname (gdbarch, data[0] - DW_OP_breg0)); |
4c2df51b DJ |
3614 | } |
3615 | ||
c3228f12 EZ |
3616 | /* The location expression for a TLS variable looks like this (on a |
3617 | 64-bit LE machine): | |
3618 | ||
3619 | DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0 | |
3620 | (DW_OP_addr: 4; DW_OP_GNU_push_tls_address) | |
09d8bd00 | 3621 | |
c3228f12 EZ |
3622 | 0x3 is the encoding for DW_OP_addr, which has an operand as long |
3623 | as the size of an address on the target machine (here is 8 | |
09d8bd00 TT |
3624 | bytes). Note that more recent version of GCC emit DW_OP_const4u |
3625 | or DW_OP_const8u, depending on address size, rather than | |
0963b4bd MS |
3626 | DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address. |
3627 | The operand represents the offset at which the variable is within | |
3628 | the thread local storage. */ | |
c3228f12 | 3629 | |
9eae7c52 | 3630 | else if (data + 1 + addr_size < end |
09d8bd00 TT |
3631 | && (data[0] == DW_OP_addr |
3632 | || (addr_size == 4 && data[0] == DW_OP_const4u) | |
3633 | || (addr_size == 8 && data[0] == DW_OP_const8u)) | |
9eae7c52 TT |
3634 | && data[1 + addr_size] == DW_OP_GNU_push_tls_address |
3635 | && piece_end_p (data + 2 + addr_size, end)) | |
08922a10 | 3636 | { |
d4a087c7 UW |
3637 | ULONGEST offset; |
3638 | offset = extract_unsigned_integer (data + 1, addr_size, | |
3639 | gdbarch_byte_order (gdbarch)); | |
9a619af0 | 3640 | |
08922a10 | 3641 | fprintf_filtered (stream, |
d4a087c7 | 3642 | _("a thread-local variable at offset 0x%s " |
08922a10 | 3643 | "in the thread-local storage for `%s'"), |
4262abfb | 3644 | phex_nz (offset, addr_size), objfile_name (objfile)); |
08922a10 SS |
3645 | |
3646 | data += 1 + addr_size + 1; | |
3647 | } | |
49f6c839 DE |
3648 | |
3649 | /* With -gsplit-dwarf a TLS variable can also look like this: | |
3650 | DW_AT_location : 3 byte block: fc 4 e0 | |
3651 | (DW_OP_GNU_const_index: 4; | |
3652 | DW_OP_GNU_push_tls_address) */ | |
3653 | else if (data + 3 <= end | |
3654 | && data + 1 + (leb128_size = skip_leb128 (data + 1, end)) < end | |
3655 | && data[0] == DW_OP_GNU_const_index | |
3656 | && leb128_size > 0 | |
3657 | && data[1 + leb128_size] == DW_OP_GNU_push_tls_address | |
3658 | && piece_end_p (data + 2 + leb128_size, end)) | |
3659 | { | |
a55c1f32 | 3660 | uint64_t offset; |
49f6c839 DE |
3661 | |
3662 | data = safe_read_uleb128 (data + 1, end, &offset); | |
3663 | offset = dwarf2_read_addr_index (per_cu, offset); | |
3664 | fprintf_filtered (stream, | |
3665 | _("a thread-local variable at offset 0x%s " | |
3666 | "in the thread-local storage for `%s'"), | |
4262abfb | 3667 | phex_nz (offset, addr_size), objfile_name (objfile)); |
49f6c839 DE |
3668 | ++data; |
3669 | } | |
3670 | ||
9eae7c52 TT |
3671 | else if (data[0] >= DW_OP_lit0 |
3672 | && data[0] <= DW_OP_lit31 | |
3673 | && data + 1 < end | |
3674 | && data[1] == DW_OP_stack_value) | |
3675 | { | |
3676 | fprintf_filtered (stream, _("the constant %d"), data[0] - DW_OP_lit0); | |
3677 | data += 2; | |
3678 | } | |
3679 | ||
3680 | return data; | |
3681 | } | |
3682 | ||
3683 | /* Disassemble an expression, stopping at the end of a piece or at the | |
3684 | end of the expression. Returns a pointer to the next unread byte | |
3685 | in the input expression. If ALL is nonzero, then this function | |
f664829e DE |
3686 | will keep going until it reaches the end of the expression. |
3687 | If there is an error during reading, e.g. we run off the end | |
3688 | of the buffer, an error is thrown. */ | |
9eae7c52 TT |
3689 | |
3690 | static const gdb_byte * | |
3691 | disassemble_dwarf_expression (struct ui_file *stream, | |
3692 | struct gdbarch *arch, unsigned int addr_size, | |
2bda9cc5 | 3693 | int offset_size, const gdb_byte *start, |
9eae7c52 | 3694 | const gdb_byte *data, const gdb_byte *end, |
2bda9cc5 | 3695 | int indent, int all, |
5e44ecb3 | 3696 | struct dwarf2_per_cu_data *per_cu) |
9eae7c52 | 3697 | { |
9eae7c52 TT |
3698 | while (data < end |
3699 | && (all | |
3700 | || (data[0] != DW_OP_piece && data[0] != DW_OP_bit_piece))) | |
3701 | { | |
3702 | enum dwarf_location_atom op = *data++; | |
9fccedf7 DE |
3703 | uint64_t ul; |
3704 | int64_t l; | |
9eae7c52 TT |
3705 | const char *name; |
3706 | ||
f39c6ffd | 3707 | name = get_DW_OP_name (op); |
9eae7c52 TT |
3708 | |
3709 | if (!name) | |
3710 | error (_("Unrecognized DWARF opcode 0x%02x at %ld"), | |
06826322 | 3711 | op, (long) (data - 1 - start)); |
2bda9cc5 JK |
3712 | fprintf_filtered (stream, " %*ld: %s", indent + 4, |
3713 | (long) (data - 1 - start), name); | |
9eae7c52 TT |
3714 | |
3715 | switch (op) | |
3716 | { | |
3717 | case DW_OP_addr: | |
d4a087c7 UW |
3718 | ul = extract_unsigned_integer (data, addr_size, |
3719 | gdbarch_byte_order (arch)); | |
9eae7c52 | 3720 | data += addr_size; |
d4a087c7 | 3721 | fprintf_filtered (stream, " 0x%s", phex_nz (ul, addr_size)); |
9eae7c52 TT |
3722 | break; |
3723 | ||
3724 | case DW_OP_const1u: | |
3725 | ul = extract_unsigned_integer (data, 1, gdbarch_byte_order (arch)); | |
3726 | data += 1; | |
3727 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
3728 | break; | |
3729 | case DW_OP_const1s: | |
3730 | l = extract_signed_integer (data, 1, gdbarch_byte_order (arch)); | |
3731 | data += 1; | |
3732 | fprintf_filtered (stream, " %s", plongest (l)); | |
3733 | break; | |
3734 | case DW_OP_const2u: | |
3735 | ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch)); | |
3736 | data += 2; | |
3737 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
3738 | break; | |
3739 | case DW_OP_const2s: | |
3740 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); | |
3741 | data += 2; | |
3742 | fprintf_filtered (stream, " %s", plongest (l)); | |
3743 | break; | |
3744 | case DW_OP_const4u: | |
3745 | ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch)); | |
3746 | data += 4; | |
3747 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
3748 | break; | |
3749 | case DW_OP_const4s: | |
3750 | l = extract_signed_integer (data, 4, gdbarch_byte_order (arch)); | |
3751 | data += 4; | |
3752 | fprintf_filtered (stream, " %s", plongest (l)); | |
3753 | break; | |
3754 | case DW_OP_const8u: | |
3755 | ul = extract_unsigned_integer (data, 8, gdbarch_byte_order (arch)); | |
3756 | data += 8; | |
3757 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
3758 | break; | |
3759 | case DW_OP_const8s: | |
3760 | l = extract_signed_integer (data, 8, gdbarch_byte_order (arch)); | |
3761 | data += 8; | |
3762 | fprintf_filtered (stream, " %s", plongest (l)); | |
3763 | break; | |
3764 | case DW_OP_constu: | |
f664829e | 3765 | data = safe_read_uleb128 (data, end, &ul); |
9eae7c52 TT |
3766 | fprintf_filtered (stream, " %s", pulongest (ul)); |
3767 | break; | |
3768 | case DW_OP_consts: | |
f664829e | 3769 | data = safe_read_sleb128 (data, end, &l); |
9eae7c52 TT |
3770 | fprintf_filtered (stream, " %s", plongest (l)); |
3771 | break; | |
3772 | ||
3773 | case DW_OP_reg0: | |
3774 | case DW_OP_reg1: | |
3775 | case DW_OP_reg2: | |
3776 | case DW_OP_reg3: | |
3777 | case DW_OP_reg4: | |
3778 | case DW_OP_reg5: | |
3779 | case DW_OP_reg6: | |
3780 | case DW_OP_reg7: | |
3781 | case DW_OP_reg8: | |
3782 | case DW_OP_reg9: | |
3783 | case DW_OP_reg10: | |
3784 | case DW_OP_reg11: | |
3785 | case DW_OP_reg12: | |
3786 | case DW_OP_reg13: | |
3787 | case DW_OP_reg14: | |
3788 | case DW_OP_reg15: | |
3789 | case DW_OP_reg16: | |
3790 | case DW_OP_reg17: | |
3791 | case DW_OP_reg18: | |
3792 | case DW_OP_reg19: | |
3793 | case DW_OP_reg20: | |
3794 | case DW_OP_reg21: | |
3795 | case DW_OP_reg22: | |
3796 | case DW_OP_reg23: | |
3797 | case DW_OP_reg24: | |
3798 | case DW_OP_reg25: | |
3799 | case DW_OP_reg26: | |
3800 | case DW_OP_reg27: | |
3801 | case DW_OP_reg28: | |
3802 | case DW_OP_reg29: | |
3803 | case DW_OP_reg30: | |
3804 | case DW_OP_reg31: | |
3805 | fprintf_filtered (stream, " [$%s]", | |
5e44ecb3 | 3806 | locexpr_regname (arch, op - DW_OP_reg0)); |
9eae7c52 TT |
3807 | break; |
3808 | ||
3809 | case DW_OP_regx: | |
f664829e | 3810 | data = safe_read_uleb128 (data, end, &ul); |
9eae7c52 | 3811 | fprintf_filtered (stream, " %s [$%s]", pulongest (ul), |
5e44ecb3 | 3812 | locexpr_regname (arch, (int) ul)); |
9eae7c52 TT |
3813 | break; |
3814 | ||
3815 | case DW_OP_implicit_value: | |
f664829e | 3816 | data = safe_read_uleb128 (data, end, &ul); |
9eae7c52 TT |
3817 | data += ul; |
3818 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
3819 | break; | |
3820 | ||
3821 | case DW_OP_breg0: | |
3822 | case DW_OP_breg1: | |
3823 | case DW_OP_breg2: | |
3824 | case DW_OP_breg3: | |
3825 | case DW_OP_breg4: | |
3826 | case DW_OP_breg5: | |
3827 | case DW_OP_breg6: | |
3828 | case DW_OP_breg7: | |
3829 | case DW_OP_breg8: | |
3830 | case DW_OP_breg9: | |
3831 | case DW_OP_breg10: | |
3832 | case DW_OP_breg11: | |
3833 | case DW_OP_breg12: | |
3834 | case DW_OP_breg13: | |
3835 | case DW_OP_breg14: | |
3836 | case DW_OP_breg15: | |
3837 | case DW_OP_breg16: | |
3838 | case DW_OP_breg17: | |
3839 | case DW_OP_breg18: | |
3840 | case DW_OP_breg19: | |
3841 | case DW_OP_breg20: | |
3842 | case DW_OP_breg21: | |
3843 | case DW_OP_breg22: | |
3844 | case DW_OP_breg23: | |
3845 | case DW_OP_breg24: | |
3846 | case DW_OP_breg25: | |
3847 | case DW_OP_breg26: | |
3848 | case DW_OP_breg27: | |
3849 | case DW_OP_breg28: | |
3850 | case DW_OP_breg29: | |
3851 | case DW_OP_breg30: | |
3852 | case DW_OP_breg31: | |
f664829e | 3853 | data = safe_read_sleb128 (data, end, &l); |
0502ed8c | 3854 | fprintf_filtered (stream, " %s [$%s]", plongest (l), |
5e44ecb3 | 3855 | locexpr_regname (arch, op - DW_OP_breg0)); |
9eae7c52 TT |
3856 | break; |
3857 | ||
3858 | case DW_OP_bregx: | |
f664829e DE |
3859 | data = safe_read_uleb128 (data, end, &ul); |
3860 | data = safe_read_sleb128 (data, end, &l); | |
0502ed8c JK |
3861 | fprintf_filtered (stream, " register %s [$%s] offset %s", |
3862 | pulongest (ul), | |
5e44ecb3 | 3863 | locexpr_regname (arch, (int) ul), |
0502ed8c | 3864 | plongest (l)); |
9eae7c52 TT |
3865 | break; |
3866 | ||
3867 | case DW_OP_fbreg: | |
f664829e | 3868 | data = safe_read_sleb128 (data, end, &l); |
0502ed8c | 3869 | fprintf_filtered (stream, " %s", plongest (l)); |
9eae7c52 TT |
3870 | break; |
3871 | ||
3872 | case DW_OP_xderef_size: | |
3873 | case DW_OP_deref_size: | |
3874 | case DW_OP_pick: | |
3875 | fprintf_filtered (stream, " %d", *data); | |
3876 | ++data; | |
3877 | break; | |
3878 | ||
3879 | case DW_OP_plus_uconst: | |
f664829e | 3880 | data = safe_read_uleb128 (data, end, &ul); |
9eae7c52 TT |
3881 | fprintf_filtered (stream, " %s", pulongest (ul)); |
3882 | break; | |
3883 | ||
3884 | case DW_OP_skip: | |
3885 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); | |
3886 | data += 2; | |
3887 | fprintf_filtered (stream, " to %ld", | |
3888 | (long) (data + l - start)); | |
3889 | break; | |
3890 | ||
3891 | case DW_OP_bra: | |
3892 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); | |
3893 | data += 2; | |
3894 | fprintf_filtered (stream, " %ld", | |
3895 | (long) (data + l - start)); | |
3896 | break; | |
3897 | ||
3898 | case DW_OP_call2: | |
3899 | ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch)); | |
3900 | data += 2; | |
3901 | fprintf_filtered (stream, " offset %s", phex_nz (ul, 2)); | |
3902 | break; | |
3903 | ||
3904 | case DW_OP_call4: | |
3905 | ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch)); | |
3906 | data += 4; | |
3907 | fprintf_filtered (stream, " offset %s", phex_nz (ul, 4)); | |
3908 | break; | |
3909 | ||
3910 | case DW_OP_call_ref: | |
3911 | ul = extract_unsigned_integer (data, offset_size, | |
3912 | gdbarch_byte_order (arch)); | |
3913 | data += offset_size; | |
3914 | fprintf_filtered (stream, " offset %s", phex_nz (ul, offset_size)); | |
3915 | break; | |
3916 | ||
3917 | case DW_OP_piece: | |
f664829e | 3918 | data = safe_read_uleb128 (data, end, &ul); |
9eae7c52 TT |
3919 | fprintf_filtered (stream, " %s (bytes)", pulongest (ul)); |
3920 | break; | |
3921 | ||
3922 | case DW_OP_bit_piece: | |
3923 | { | |
9fccedf7 | 3924 | uint64_t offset; |
9eae7c52 | 3925 | |
f664829e DE |
3926 | data = safe_read_uleb128 (data, end, &ul); |
3927 | data = safe_read_uleb128 (data, end, &offset); | |
9eae7c52 TT |
3928 | fprintf_filtered (stream, " size %s offset %s (bits)", |
3929 | pulongest (ul), pulongest (offset)); | |
3930 | } | |
3931 | break; | |
8cf6f0b1 TT |
3932 | |
3933 | case DW_OP_GNU_implicit_pointer: | |
3934 | { | |
3935 | ul = extract_unsigned_integer (data, offset_size, | |
3936 | gdbarch_byte_order (arch)); | |
3937 | data += offset_size; | |
3938 | ||
f664829e | 3939 | data = safe_read_sleb128 (data, end, &l); |
8cf6f0b1 TT |
3940 | |
3941 | fprintf_filtered (stream, " DIE %s offset %s", | |
3942 | phex_nz (ul, offset_size), | |
3943 | plongest (l)); | |
3944 | } | |
3945 | break; | |
5e44ecb3 TT |
3946 | |
3947 | case DW_OP_GNU_deref_type: | |
3948 | { | |
3949 | int addr_size = *data++; | |
b64f50a1 | 3950 | cu_offset offset; |
5e44ecb3 TT |
3951 | struct type *type; |
3952 | ||
f664829e | 3953 | data = safe_read_uleb128 (data, end, &ul); |
b64f50a1 | 3954 | offset.cu_off = ul; |
5e44ecb3 TT |
3955 | type = dwarf2_get_die_type (offset, per_cu); |
3956 | fprintf_filtered (stream, "<"); | |
3957 | type_print (type, "", stream, -1); | |
b64f50a1 | 3958 | fprintf_filtered (stream, " [0x%s]> %d", phex_nz (offset.cu_off, 0), |
5e44ecb3 TT |
3959 | addr_size); |
3960 | } | |
3961 | break; | |
3962 | ||
3963 | case DW_OP_GNU_const_type: | |
3964 | { | |
b64f50a1 | 3965 | cu_offset type_die; |
5e44ecb3 TT |
3966 | struct type *type; |
3967 | ||
f664829e | 3968 | data = safe_read_uleb128 (data, end, &ul); |
b64f50a1 | 3969 | type_die.cu_off = ul; |
5e44ecb3 TT |
3970 | type = dwarf2_get_die_type (type_die, per_cu); |
3971 | fprintf_filtered (stream, "<"); | |
3972 | type_print (type, "", stream, -1); | |
b64f50a1 | 3973 | fprintf_filtered (stream, " [0x%s]>", phex_nz (type_die.cu_off, 0)); |
5e44ecb3 TT |
3974 | } |
3975 | break; | |
3976 | ||
3977 | case DW_OP_GNU_regval_type: | |
3978 | { | |
9fccedf7 | 3979 | uint64_t reg; |
b64f50a1 | 3980 | cu_offset type_die; |
5e44ecb3 TT |
3981 | struct type *type; |
3982 | ||
f664829e DE |
3983 | data = safe_read_uleb128 (data, end, ®); |
3984 | data = safe_read_uleb128 (data, end, &ul); | |
b64f50a1 | 3985 | type_die.cu_off = ul; |
5e44ecb3 TT |
3986 | |
3987 | type = dwarf2_get_die_type (type_die, per_cu); | |
3988 | fprintf_filtered (stream, "<"); | |
3989 | type_print (type, "", stream, -1); | |
b64f50a1 JK |
3990 | fprintf_filtered (stream, " [0x%s]> [$%s]", |
3991 | phex_nz (type_die.cu_off, 0), | |
5e44ecb3 TT |
3992 | locexpr_regname (arch, reg)); |
3993 | } | |
3994 | break; | |
3995 | ||
3996 | case DW_OP_GNU_convert: | |
3997 | case DW_OP_GNU_reinterpret: | |
3998 | { | |
b64f50a1 | 3999 | cu_offset type_die; |
5e44ecb3 | 4000 | |
f664829e | 4001 | data = safe_read_uleb128 (data, end, &ul); |
b64f50a1 | 4002 | type_die.cu_off = ul; |
5e44ecb3 | 4003 | |
b64f50a1 | 4004 | if (type_die.cu_off == 0) |
5e44ecb3 TT |
4005 | fprintf_filtered (stream, "<0>"); |
4006 | else | |
4007 | { | |
4008 | struct type *type; | |
4009 | ||
4010 | type = dwarf2_get_die_type (type_die, per_cu); | |
4011 | fprintf_filtered (stream, "<"); | |
4012 | type_print (type, "", stream, -1); | |
b64f50a1 | 4013 | fprintf_filtered (stream, " [0x%s]>", phex_nz (type_die.cu_off, 0)); |
5e44ecb3 TT |
4014 | } |
4015 | } | |
4016 | break; | |
2bda9cc5 JK |
4017 | |
4018 | case DW_OP_GNU_entry_value: | |
f664829e | 4019 | data = safe_read_uleb128 (data, end, &ul); |
2bda9cc5 JK |
4020 | fputc_filtered ('\n', stream); |
4021 | disassemble_dwarf_expression (stream, arch, addr_size, offset_size, | |
4022 | start, data, data + ul, indent + 2, | |
4023 | all, per_cu); | |
4024 | data += ul; | |
4025 | continue; | |
49f6c839 | 4026 | |
a24f71ab JK |
4027 | case DW_OP_GNU_parameter_ref: |
4028 | ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch)); | |
4029 | data += 4; | |
4030 | fprintf_filtered (stream, " offset %s", phex_nz (ul, 4)); | |
4031 | break; | |
4032 | ||
49f6c839 DE |
4033 | case DW_OP_GNU_addr_index: |
4034 | data = safe_read_uleb128 (data, end, &ul); | |
4035 | ul = dwarf2_read_addr_index (per_cu, ul); | |
4036 | fprintf_filtered (stream, " 0x%s", phex_nz (ul, addr_size)); | |
4037 | break; | |
4038 | case DW_OP_GNU_const_index: | |
4039 | data = safe_read_uleb128 (data, end, &ul); | |
4040 | ul = dwarf2_read_addr_index (per_cu, ul); | |
4041 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
4042 | break; | |
9eae7c52 TT |
4043 | } |
4044 | ||
4045 | fprintf_filtered (stream, "\n"); | |
4046 | } | |
c3228f12 | 4047 | |
08922a10 | 4048 | return data; |
4c2df51b DJ |
4049 | } |
4050 | ||
08922a10 SS |
4051 | /* Describe a single location, which may in turn consist of multiple |
4052 | pieces. */ | |
a55cc764 | 4053 | |
08922a10 SS |
4054 | static void |
4055 | locexpr_describe_location_1 (struct symbol *symbol, CORE_ADDR addr, | |
0d45f56e | 4056 | struct ui_file *stream, |
56eb65bd | 4057 | const gdb_byte *data, size_t size, |
9eae7c52 | 4058 | struct objfile *objfile, unsigned int addr_size, |
5e44ecb3 | 4059 | int offset_size, struct dwarf2_per_cu_data *per_cu) |
08922a10 | 4060 | { |
0d45f56e | 4061 | const gdb_byte *end = data + size; |
9eae7c52 | 4062 | int first_piece = 1, bad = 0; |
08922a10 | 4063 | |
08922a10 SS |
4064 | while (data < end) |
4065 | { | |
9eae7c52 TT |
4066 | const gdb_byte *here = data; |
4067 | int disassemble = 1; | |
4068 | ||
4069 | if (first_piece) | |
4070 | first_piece = 0; | |
4071 | else | |
4072 | fprintf_filtered (stream, _(", and ")); | |
08922a10 | 4073 | |
9eae7c52 TT |
4074 | if (!dwarf2_always_disassemble) |
4075 | { | |
3e43a32a | 4076 | data = locexpr_describe_location_piece (symbol, stream, |
49f6c839 | 4077 | addr, objfile, per_cu, |
9eae7c52 TT |
4078 | data, end, addr_size); |
4079 | /* If we printed anything, or if we have an empty piece, | |
4080 | then don't disassemble. */ | |
4081 | if (data != here | |
4082 | || data[0] == DW_OP_piece | |
4083 | || data[0] == DW_OP_bit_piece) | |
4084 | disassemble = 0; | |
08922a10 | 4085 | } |
9eae7c52 | 4086 | if (disassemble) |
2bda9cc5 JK |
4087 | { |
4088 | fprintf_filtered (stream, _("a complex DWARF expression:\n")); | |
4089 | data = disassemble_dwarf_expression (stream, | |
4090 | get_objfile_arch (objfile), | |
4091 | addr_size, offset_size, data, | |
4092 | data, end, 0, | |
4093 | dwarf2_always_disassemble, | |
4094 | per_cu); | |
4095 | } | |
9eae7c52 TT |
4096 | |
4097 | if (data < end) | |
08922a10 | 4098 | { |
9eae7c52 | 4099 | int empty = data == here; |
08922a10 | 4100 | |
9eae7c52 TT |
4101 | if (disassemble) |
4102 | fprintf_filtered (stream, " "); | |
4103 | if (data[0] == DW_OP_piece) | |
4104 | { | |
9fccedf7 | 4105 | uint64_t bytes; |
08922a10 | 4106 | |
f664829e | 4107 | data = safe_read_uleb128 (data + 1, end, &bytes); |
08922a10 | 4108 | |
9eae7c52 TT |
4109 | if (empty) |
4110 | fprintf_filtered (stream, _("an empty %s-byte piece"), | |
4111 | pulongest (bytes)); | |
4112 | else | |
4113 | fprintf_filtered (stream, _(" [%s-byte piece]"), | |
4114 | pulongest (bytes)); | |
4115 | } | |
4116 | else if (data[0] == DW_OP_bit_piece) | |
4117 | { | |
9fccedf7 | 4118 | uint64_t bits, offset; |
9eae7c52 | 4119 | |
f664829e DE |
4120 | data = safe_read_uleb128 (data + 1, end, &bits); |
4121 | data = safe_read_uleb128 (data, end, &offset); | |
9eae7c52 TT |
4122 | |
4123 | if (empty) | |
4124 | fprintf_filtered (stream, | |
4125 | _("an empty %s-bit piece"), | |
4126 | pulongest (bits)); | |
4127 | else | |
4128 | fprintf_filtered (stream, | |
4129 | _(" [%s-bit piece, offset %s bits]"), | |
4130 | pulongest (bits), pulongest (offset)); | |
4131 | } | |
4132 | else | |
4133 | { | |
4134 | bad = 1; | |
4135 | break; | |
4136 | } | |
08922a10 SS |
4137 | } |
4138 | } | |
4139 | ||
4140 | if (bad || data > end) | |
4141 | error (_("Corrupted DWARF2 expression for \"%s\"."), | |
4142 | SYMBOL_PRINT_NAME (symbol)); | |
4143 | } | |
4144 | ||
4145 | /* Print a natural-language description of SYMBOL to STREAM. This | |
4146 | version is for a symbol with a single location. */ | |
a55cc764 | 4147 | |
08922a10 SS |
4148 | static void |
4149 | locexpr_describe_location (struct symbol *symbol, CORE_ADDR addr, | |
4150 | struct ui_file *stream) | |
4151 | { | |
4152 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
4153 | struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu); | |
4154 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); | |
9eae7c52 | 4155 | int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu); |
08922a10 | 4156 | |
3e43a32a MS |
4157 | locexpr_describe_location_1 (symbol, addr, stream, |
4158 | dlbaton->data, dlbaton->size, | |
5e44ecb3 TT |
4159 | objfile, addr_size, offset_size, |
4160 | dlbaton->per_cu); | |
08922a10 SS |
4161 | } |
4162 | ||
4163 | /* Describe the location of SYMBOL as an agent value in VALUE, generating | |
4164 | any necessary bytecode in AX. */ | |
a55cc764 | 4165 | |
0d53c4c4 | 4166 | static void |
505e835d UW |
4167 | locexpr_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch, |
4168 | struct agent_expr *ax, struct axs_value *value) | |
a55cc764 DJ |
4169 | { |
4170 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
3cf03773 | 4171 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); |
a55cc764 | 4172 | |
1d6edc3c | 4173 | if (dlbaton->size == 0) |
cabe9ab6 PA |
4174 | value->optimized_out = 1; |
4175 | else | |
9f6f94ff TT |
4176 | dwarf2_compile_expr_to_ax (ax, value, gdbarch, addr_size, |
4177 | dlbaton->data, dlbaton->data + dlbaton->size, | |
4178 | dlbaton->per_cu); | |
a55cc764 DJ |
4179 | } |
4180 | ||
4c2df51b DJ |
4181 | /* The set of location functions used with the DWARF-2 expression |
4182 | evaluator. */ | |
768a979c | 4183 | const struct symbol_computed_ops dwarf2_locexpr_funcs = { |
4c2df51b | 4184 | locexpr_read_variable, |
e18b2753 | 4185 | locexpr_read_variable_at_entry, |
4c2df51b DJ |
4186 | locexpr_read_needs_frame, |
4187 | locexpr_describe_location, | |
f1e6e072 | 4188 | 0, /* location_has_loclist */ |
a55cc764 | 4189 | locexpr_tracepoint_var_ref |
4c2df51b | 4190 | }; |
0d53c4c4 DJ |
4191 | |
4192 | ||
4193 | /* Wrapper functions for location lists. These generally find | |
4194 | the appropriate location expression and call something above. */ | |
4195 | ||
4196 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression | |
4197 | evaluator to calculate the location. */ | |
4198 | static struct value * | |
4199 | loclist_read_variable (struct symbol *symbol, struct frame_info *frame) | |
4200 | { | |
4201 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
4202 | struct value *val; | |
947bb88f | 4203 | const gdb_byte *data; |
b6b08ebf | 4204 | size_t size; |
8cf6f0b1 | 4205 | CORE_ADDR pc = frame ? get_frame_address_in_block (frame) : 0; |
0d53c4c4 | 4206 | |
8cf6f0b1 | 4207 | data = dwarf2_find_location_expression (dlbaton, &size, pc); |
1d6edc3c JK |
4208 | val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, data, size, |
4209 | dlbaton->per_cu); | |
0d53c4c4 DJ |
4210 | |
4211 | return val; | |
4212 | } | |
4213 | ||
e18b2753 JK |
4214 | /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function |
4215 | entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR | |
4216 | will be thrown. | |
4217 | ||
4218 | Function always returns non-NULL value, it may be marked optimized out if | |
4219 | inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR | |
4220 | if it cannot resolve the parameter for any reason. */ | |
4221 | ||
4222 | static struct value * | |
4223 | loclist_read_variable_at_entry (struct symbol *symbol, struct frame_info *frame) | |
4224 | { | |
4225 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
4226 | const gdb_byte *data; | |
4227 | size_t size; | |
4228 | CORE_ADDR pc; | |
4229 | ||
4230 | if (frame == NULL || !get_frame_func_if_available (frame, &pc)) | |
4231 | return allocate_optimized_out_value (SYMBOL_TYPE (symbol)); | |
4232 | ||
4233 | data = dwarf2_find_location_expression (dlbaton, &size, pc); | |
4234 | if (data == NULL) | |
4235 | return allocate_optimized_out_value (SYMBOL_TYPE (symbol)); | |
4236 | ||
4237 | return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol), frame, data, size); | |
4238 | } | |
4239 | ||
0d53c4c4 DJ |
4240 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ |
4241 | static int | |
4242 | loclist_read_needs_frame (struct symbol *symbol) | |
4243 | { | |
4244 | /* If there's a location list, then assume we need to have a frame | |
4245 | to choose the appropriate location expression. With tracking of | |
4246 | global variables this is not necessarily true, but such tracking | |
4247 | is disabled in GCC at the moment until we figure out how to | |
4248 | represent it. */ | |
4249 | ||
4250 | return 1; | |
4251 | } | |
4252 | ||
08922a10 SS |
4253 | /* Print a natural-language description of SYMBOL to STREAM. This |
4254 | version applies when there is a list of different locations, each | |
4255 | with a specified address range. */ | |
4256 | ||
4257 | static void | |
4258 | loclist_describe_location (struct symbol *symbol, CORE_ADDR addr, | |
4259 | struct ui_file *stream) | |
0d53c4c4 | 4260 | { |
08922a10 | 4261 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
947bb88f | 4262 | const gdb_byte *loc_ptr, *buf_end; |
08922a10 SS |
4263 | struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu); |
4264 | struct gdbarch *gdbarch = get_objfile_arch (objfile); | |
4265 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); | |
4266 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); | |
9eae7c52 | 4267 | int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu); |
d4a087c7 | 4268 | int signed_addr_p = bfd_get_sign_extend_vma (objfile->obfd); |
08922a10 | 4269 | /* Adjust base_address for relocatable objects. */ |
9aa1f1e3 | 4270 | CORE_ADDR base_offset = dwarf2_per_cu_text_offset (dlbaton->per_cu); |
08922a10 | 4271 | CORE_ADDR base_address = dlbaton->base_address + base_offset; |
f664829e | 4272 | int done = 0; |
08922a10 SS |
4273 | |
4274 | loc_ptr = dlbaton->data; | |
4275 | buf_end = dlbaton->data + dlbaton->size; | |
4276 | ||
9eae7c52 | 4277 | fprintf_filtered (stream, _("multi-location:\n")); |
08922a10 SS |
4278 | |
4279 | /* Iterate through locations until we run out. */ | |
f664829e | 4280 | while (!done) |
08922a10 | 4281 | { |
f664829e DE |
4282 | CORE_ADDR low = 0, high = 0; /* init for gcc -Wall */ |
4283 | int length; | |
4284 | enum debug_loc_kind kind; | |
4285 | const gdb_byte *new_ptr = NULL; /* init for gcc -Wall */ | |
4286 | ||
4287 | if (dlbaton->from_dwo) | |
4288 | kind = decode_debug_loc_dwo_addresses (dlbaton->per_cu, | |
4289 | loc_ptr, buf_end, &new_ptr, | |
3771a44c | 4290 | &low, &high, byte_order); |
d4a087c7 | 4291 | else |
f664829e DE |
4292 | kind = decode_debug_loc_addresses (loc_ptr, buf_end, &new_ptr, |
4293 | &low, &high, | |
4294 | byte_order, addr_size, | |
4295 | signed_addr_p); | |
4296 | loc_ptr = new_ptr; | |
4297 | switch (kind) | |
08922a10 | 4298 | { |
f664829e DE |
4299 | case DEBUG_LOC_END_OF_LIST: |
4300 | done = 1; | |
4301 | continue; | |
4302 | case DEBUG_LOC_BASE_ADDRESS: | |
d4a087c7 | 4303 | base_address = high + base_offset; |
9eae7c52 | 4304 | fprintf_filtered (stream, _(" Base address %s"), |
08922a10 | 4305 | paddress (gdbarch, base_address)); |
08922a10 | 4306 | continue; |
3771a44c DE |
4307 | case DEBUG_LOC_START_END: |
4308 | case DEBUG_LOC_START_LENGTH: | |
f664829e DE |
4309 | break; |
4310 | case DEBUG_LOC_BUFFER_OVERFLOW: | |
4311 | case DEBUG_LOC_INVALID_ENTRY: | |
4312 | error (_("Corrupted DWARF expression for symbol \"%s\"."), | |
4313 | SYMBOL_PRINT_NAME (symbol)); | |
4314 | default: | |
4315 | gdb_assert_not_reached ("bad debug_loc_kind"); | |
08922a10 SS |
4316 | } |
4317 | ||
08922a10 SS |
4318 | /* Otherwise, a location expression entry. */ |
4319 | low += base_address; | |
4320 | high += base_address; | |
4321 | ||
4322 | length = extract_unsigned_integer (loc_ptr, 2, byte_order); | |
4323 | loc_ptr += 2; | |
4324 | ||
08922a10 SS |
4325 | /* (It would improve readability to print only the minimum |
4326 | necessary digits of the second number of the range.) */ | |
9eae7c52 | 4327 | fprintf_filtered (stream, _(" Range %s-%s: "), |
08922a10 SS |
4328 | paddress (gdbarch, low), paddress (gdbarch, high)); |
4329 | ||
4330 | /* Now describe this particular location. */ | |
4331 | locexpr_describe_location_1 (symbol, low, stream, loc_ptr, length, | |
5e44ecb3 TT |
4332 | objfile, addr_size, offset_size, |
4333 | dlbaton->per_cu); | |
9eae7c52 TT |
4334 | |
4335 | fprintf_filtered (stream, "\n"); | |
08922a10 SS |
4336 | |
4337 | loc_ptr += length; | |
4338 | } | |
0d53c4c4 DJ |
4339 | } |
4340 | ||
4341 | /* Describe the location of SYMBOL as an agent value in VALUE, generating | |
4342 | any necessary bytecode in AX. */ | |
4343 | static void | |
505e835d UW |
4344 | loclist_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch, |
4345 | struct agent_expr *ax, struct axs_value *value) | |
0d53c4c4 DJ |
4346 | { |
4347 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
947bb88f | 4348 | const gdb_byte *data; |
b6b08ebf | 4349 | size_t size; |
3cf03773 | 4350 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); |
0d53c4c4 | 4351 | |
8cf6f0b1 | 4352 | data = dwarf2_find_location_expression (dlbaton, &size, ax->scope); |
1d6edc3c | 4353 | if (size == 0) |
cabe9ab6 PA |
4354 | value->optimized_out = 1; |
4355 | else | |
9f6f94ff TT |
4356 | dwarf2_compile_expr_to_ax (ax, value, gdbarch, addr_size, data, data + size, |
4357 | dlbaton->per_cu); | |
0d53c4c4 DJ |
4358 | } |
4359 | ||
4360 | /* The set of location functions used with the DWARF-2 expression | |
4361 | evaluator and location lists. */ | |
768a979c | 4362 | const struct symbol_computed_ops dwarf2_loclist_funcs = { |
0d53c4c4 | 4363 | loclist_read_variable, |
e18b2753 | 4364 | loclist_read_variable_at_entry, |
0d53c4c4 DJ |
4365 | loclist_read_needs_frame, |
4366 | loclist_describe_location, | |
f1e6e072 | 4367 | 1, /* location_has_loclist */ |
0d53c4c4 DJ |
4368 | loclist_tracepoint_var_ref |
4369 | }; | |
8e3b41a9 | 4370 | |
70221824 PA |
4371 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
4372 | extern initialize_file_ftype _initialize_dwarf2loc; | |
4373 | ||
8e3b41a9 JK |
4374 | void |
4375 | _initialize_dwarf2loc (void) | |
4376 | { | |
ccce17b0 YQ |
4377 | add_setshow_zuinteger_cmd ("entry-values", class_maintenance, |
4378 | &entry_values_debug, | |
4379 | _("Set entry values and tail call frames " | |
4380 | "debugging."), | |
4381 | _("Show entry values and tail call frames " | |
4382 | "debugging."), | |
4383 | _("When non-zero, the process of determining " | |
4384 | "parameter values from function entry point " | |
4385 | "and tail call frames will be printed."), | |
4386 | NULL, | |
4387 | show_entry_values_debug, | |
4388 | &setdebuglist, &showdebuglist); | |
8e3b41a9 | 4389 | } |