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4c2df51b DJ |
1 | /* DWARF 2 location expression support for GDB. |
2 | Copyright 2003 Free Software Foundation, Inc. | |
3 | Contributed by Daniel Jacobowitz, MontaVista Software, Inc. | |
4 | ||
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2 of the License, or (at | |
10 | your option) any later version. | |
11 | ||
12 | This program is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 59 Temple Place - Suite 330, | |
20 | Boston, MA 02111-1307, USA. */ | |
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" |
4c2df51b DJ |
33 | |
34 | #include "elf/dwarf2.h" | |
35 | #include "dwarf2expr.h" | |
36 | #include "dwarf2loc.h" | |
37 | ||
38 | #include "gdb_string.h" | |
39 | ||
40 | #ifndef DWARF2_REG_TO_REGNUM | |
41 | #define DWARF2_REG_TO_REGNUM(REG) (REG) | |
42 | #endif | |
43 | ||
0d53c4c4 DJ |
44 | /* A helper function for dealing with location lists. Given a |
45 | symbol baton (BATON) and a pc value (PC), find the appropriate | |
46 | location expression, set *LOCEXPR_LENGTH, and return a pointer | |
47 | to the beginning of the expression. Returns NULL on failure. | |
48 | ||
49 | For now, only return the first matching location expression; there | |
50 | can be more than one in the list. */ | |
51 | ||
52 | static char * | |
53 | find_location_expression (struct dwarf2_loclist_baton *baton, | |
b6b08ebf | 54 | size_t *locexpr_length, CORE_ADDR pc) |
0d53c4c4 | 55 | { |
0d53c4c4 DJ |
56 | CORE_ADDR low, high; |
57 | char *loc_ptr, *buf_end; | |
58 | unsigned int addr_size = TARGET_ADDR_BIT / TARGET_CHAR_BIT, length; | |
59 | CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1)); | |
8edfa926 BM |
60 | /* Adjust base_address for relocatable objects. */ |
61 | CORE_ADDR base_offset = ANOFFSET (baton->objfile->section_offsets, | |
62 | SECT_OFF_TEXT (baton->objfile)); | |
63 | CORE_ADDR base_address = baton->base_address + base_offset; | |
0d53c4c4 DJ |
64 | |
65 | loc_ptr = baton->data; | |
66 | buf_end = baton->data + baton->size; | |
67 | ||
68 | while (1) | |
69 | { | |
70 | low = dwarf2_read_address (loc_ptr, buf_end, &length); | |
71 | loc_ptr += length; | |
72 | high = dwarf2_read_address (loc_ptr, buf_end, &length); | |
73 | loc_ptr += length; | |
74 | ||
75 | /* An end-of-list entry. */ | |
76 | if (low == 0 && high == 0) | |
77 | return NULL; | |
78 | ||
79 | /* A base-address-selection entry. */ | |
80 | if ((low & base_mask) == base_mask) | |
81 | { | |
82 | base_address = high; | |
83 | continue; | |
84 | } | |
85 | ||
86 | /* Otherwise, a location expression entry. */ | |
87 | low += base_address; | |
88 | high += base_address; | |
89 | ||
90 | length = extract_unsigned_integer (loc_ptr, 2); | |
91 | loc_ptr += 2; | |
92 | ||
93 | if (pc >= low && pc < high) | |
94 | { | |
95 | *locexpr_length = length; | |
96 | return loc_ptr; | |
97 | } | |
98 | ||
99 | loc_ptr += length; | |
100 | } | |
101 | } | |
102 | ||
4c2df51b DJ |
103 | /* This is the baton used when performing dwarf2 expression |
104 | evaluation. */ | |
105 | struct dwarf_expr_baton | |
106 | { | |
107 | struct frame_info *frame; | |
108 | struct objfile *objfile; | |
109 | }; | |
110 | ||
111 | /* Helper functions for dwarf2_evaluate_loc_desc. */ | |
112 | ||
113 | /* Using the frame specified in BATON, read register REGNUM. The lval | |
114 | type will be returned in LVALP, and for lval_memory the register | |
115 | save address will be returned in ADDRP. */ | |
116 | static CORE_ADDR | |
61fbb938 | 117 | dwarf_expr_read_reg (void *baton, int dwarf_regnum) |
4c2df51b | 118 | { |
4c2df51b | 119 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
61fbb938 DJ |
120 | CORE_ADDR result, save_addr; |
121 | enum lval_type lval_type; | |
e4adbba9 DJ |
122 | char *buf; |
123 | int optimized, regnum, realnum, regsize; | |
124 | ||
125 | regnum = DWARF2_REG_TO_REGNUM (dwarf_regnum); | |
126 | regsize = register_size (current_gdbarch, regnum); | |
127 | buf = (char *) alloca (regsize); | |
4c2df51b | 128 | |
61fbb938 DJ |
129 | frame_register (debaton->frame, regnum, &optimized, &lval_type, &save_addr, |
130 | &realnum, buf); | |
af1342ab AC |
131 | /* NOTE: cagney/2003-05-22: This extract is assuming that a DWARF 2 |
132 | address is always unsigned. That may or may not be true. */ | |
133 | result = extract_unsigned_integer (buf, regsize); | |
4c2df51b DJ |
134 | |
135 | return result; | |
136 | } | |
137 | ||
138 | /* Read memory at ADDR (length LEN) into BUF. */ | |
139 | ||
140 | static void | |
141 | dwarf_expr_read_mem (void *baton, char *buf, CORE_ADDR addr, size_t len) | |
142 | { | |
143 | read_memory (addr, buf, len); | |
144 | } | |
145 | ||
146 | /* Using the frame specified in BATON, find the location expression | |
147 | describing the frame base. Return a pointer to it in START and | |
148 | its length in LENGTH. */ | |
149 | static void | |
150 | dwarf_expr_frame_base (void *baton, unsigned char **start, size_t * length) | |
151 | { | |
da62e633 AC |
152 | /* FIXME: cagney/2003-03-26: This code should be using |
153 | get_frame_base_address(), and then implement a dwarf2 specific | |
154 | this_base method. */ | |
4c2df51b | 155 | struct symbol *framefunc; |
4c2df51b | 156 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
0d53c4c4 | 157 | |
4c2df51b | 158 | framefunc = get_frame_function (debaton->frame); |
0d53c4c4 | 159 | |
a67af2b9 | 160 | if (SYMBOL_OPS (framefunc) == &dwarf2_loclist_funcs) |
0d53c4c4 DJ |
161 | { |
162 | struct dwarf2_loclist_baton *symbaton; | |
163 | symbaton = SYMBOL_LOCATION_BATON (framefunc); | |
164 | *start = find_location_expression (symbaton, length, | |
165 | get_frame_pc (debaton->frame)); | |
166 | } | |
167 | else | |
168 | { | |
169 | struct dwarf2_locexpr_baton *symbaton; | |
170 | symbaton = SYMBOL_LOCATION_BATON (framefunc); | |
171 | *length = symbaton->size; | |
172 | *start = symbaton->data; | |
173 | } | |
174 | ||
175 | if (*start == NULL) | |
176 | error ("Could not find the frame base for \"%s\".", | |
177 | SYMBOL_NATURAL_NAME (framefunc)); | |
4c2df51b DJ |
178 | } |
179 | ||
180 | /* Using the objfile specified in BATON, find the address for the | |
181 | current thread's thread-local storage with offset OFFSET. */ | |
182 | static CORE_ADDR | |
183 | dwarf_expr_tls_address (void *baton, CORE_ADDR offset) | |
184 | { | |
185 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
186 | CORE_ADDR addr; | |
187 | ||
188 | if (target_get_thread_local_address_p ()) | |
189 | addr = target_get_thread_local_address (inferior_ptid, | |
190 | debaton->objfile, | |
191 | offset); | |
c3228f12 EZ |
192 | /* It wouldn't be wrong here to try a gdbarch method, too; finding |
193 | TLS is an ABI-specific thing. But we don't do that yet. */ | |
4c2df51b DJ |
194 | else |
195 | error ("Cannot find thread-local variables on this target"); | |
196 | ||
197 | return addr; | |
198 | } | |
199 | ||
200 | /* Evaluate a location description, starting at DATA and with length | |
201 | SIZE, to find the current location of variable VAR in the context | |
202 | of FRAME. */ | |
203 | static struct value * | |
204 | dwarf2_evaluate_loc_desc (struct symbol *var, struct frame_info *frame, | |
205 | unsigned char *data, unsigned short size, | |
206 | struct objfile *objfile) | |
207 | { | |
208 | CORE_ADDR result; | |
209 | struct value *retval; | |
210 | struct dwarf_expr_baton baton; | |
211 | struct dwarf_expr_context *ctx; | |
212 | ||
0d53c4c4 DJ |
213 | if (size == 0) |
214 | { | |
215 | retval = allocate_value (SYMBOL_TYPE (var)); | |
216 | VALUE_LVAL (retval) = not_lval; | |
217 | VALUE_OPTIMIZED_OUT (retval) = 1; | |
218 | } | |
219 | ||
4c2df51b DJ |
220 | baton.frame = frame; |
221 | baton.objfile = objfile; | |
222 | ||
223 | ctx = new_dwarf_expr_context (); | |
224 | ctx->baton = &baton; | |
225 | ctx->read_reg = dwarf_expr_read_reg; | |
226 | ctx->read_mem = dwarf_expr_read_mem; | |
227 | ctx->get_frame_base = dwarf_expr_frame_base; | |
228 | ctx->get_tls_address = dwarf_expr_tls_address; | |
229 | ||
230 | dwarf_expr_eval (ctx, data, size); | |
61fbb938 | 231 | result = dwarf_expr_fetch (ctx, 0); |
4c2df51b DJ |
232 | |
233 | if (ctx->in_reg) | |
051caad9 KB |
234 | { |
235 | int regnum = DWARF2_REG_TO_REGNUM (result); | |
236 | retval = value_from_register (SYMBOL_TYPE (var), regnum, frame); | |
237 | } | |
4c2df51b DJ |
238 | else |
239 | { | |
61fbb938 DJ |
240 | retval = allocate_value (SYMBOL_TYPE (var)); |
241 | VALUE_BFD_SECTION (retval) = SYMBOL_BFD_SECTION (var); | |
242 | ||
4c2df51b DJ |
243 | VALUE_LVAL (retval) = lval_memory; |
244 | VALUE_LAZY (retval) = 1; | |
245 | VALUE_ADDRESS (retval) = result; | |
246 | } | |
247 | ||
248 | free_dwarf_expr_context (ctx); | |
249 | ||
250 | return retval; | |
251 | } | |
252 | ||
253 | ||
254 | ||
255 | ||
256 | \f | |
257 | /* Helper functions and baton for dwarf2_loc_desc_needs_frame. */ | |
258 | ||
259 | struct needs_frame_baton | |
260 | { | |
261 | int needs_frame; | |
262 | }; | |
263 | ||
264 | /* Reads from registers do require a frame. */ | |
265 | static CORE_ADDR | |
61fbb938 | 266 | needs_frame_read_reg (void *baton, int regnum) |
4c2df51b DJ |
267 | { |
268 | struct needs_frame_baton *nf_baton = baton; | |
269 | nf_baton->needs_frame = 1; | |
270 | return 1; | |
271 | } | |
272 | ||
273 | /* Reads from memory do not require a frame. */ | |
274 | static void | |
275 | needs_frame_read_mem (void *baton, char *buf, CORE_ADDR addr, size_t len) | |
276 | { | |
277 | memset (buf, 0, len); | |
278 | } | |
279 | ||
280 | /* Frame-relative accesses do require a frame. */ | |
281 | static void | |
282 | needs_frame_frame_base (void *baton, unsigned char **start, size_t * length) | |
283 | { | |
284 | static char lit0 = DW_OP_lit0; | |
285 | struct needs_frame_baton *nf_baton = baton; | |
286 | ||
287 | *start = &lit0; | |
288 | *length = 1; | |
289 | ||
290 | nf_baton->needs_frame = 1; | |
291 | } | |
292 | ||
293 | /* Thread-local accesses do require a frame. */ | |
294 | static CORE_ADDR | |
295 | needs_frame_tls_address (void *baton, CORE_ADDR offset) | |
296 | { | |
297 | struct needs_frame_baton *nf_baton = baton; | |
298 | nf_baton->needs_frame = 1; | |
299 | return 1; | |
300 | } | |
301 | ||
302 | /* Return non-zero iff the location expression at DATA (length SIZE) | |
303 | requires a frame to evaluate. */ | |
304 | ||
305 | static int | |
306 | dwarf2_loc_desc_needs_frame (unsigned char *data, unsigned short size) | |
307 | { | |
308 | struct needs_frame_baton baton; | |
309 | struct dwarf_expr_context *ctx; | |
f630a401 | 310 | int in_reg; |
4c2df51b DJ |
311 | |
312 | baton.needs_frame = 0; | |
313 | ||
314 | ctx = new_dwarf_expr_context (); | |
315 | ctx->baton = &baton; | |
316 | ctx->read_reg = needs_frame_read_reg; | |
317 | ctx->read_mem = needs_frame_read_mem; | |
318 | ctx->get_frame_base = needs_frame_frame_base; | |
319 | ctx->get_tls_address = needs_frame_tls_address; | |
320 | ||
321 | dwarf_expr_eval (ctx, data, size); | |
322 | ||
f630a401 DJ |
323 | in_reg = ctx->in_reg; |
324 | ||
4c2df51b DJ |
325 | free_dwarf_expr_context (ctx); |
326 | ||
f630a401 | 327 | return baton.needs_frame || in_reg; |
4c2df51b DJ |
328 | } |
329 | ||
0d53c4c4 DJ |
330 | static void |
331 | dwarf2_tracepoint_var_ref (struct symbol * symbol, struct agent_expr * ax, | |
332 | struct axs_value * value, unsigned char *data, | |
333 | int size) | |
334 | { | |
335 | if (size == 0) | |
336 | error ("Symbol \"%s\" has been optimized out.", | |
337 | SYMBOL_PRINT_NAME (symbol)); | |
338 | ||
339 | if (size == 1 | |
340 | && data[0] >= DW_OP_reg0 | |
341 | && data[0] <= DW_OP_reg31) | |
342 | { | |
343 | value->kind = axs_lvalue_register; | |
344 | value->u.reg = data[0] - DW_OP_reg0; | |
345 | } | |
346 | else if (data[0] == DW_OP_regx) | |
347 | { | |
348 | ULONGEST reg; | |
349 | read_uleb128 (data + 1, data + size, ®); | |
350 | value->kind = axs_lvalue_register; | |
351 | value->u.reg = reg; | |
352 | } | |
353 | else if (data[0] == DW_OP_fbreg) | |
354 | { | |
355 | /* And this is worse than just minimal; we should honor the frame base | |
356 | as above. */ | |
357 | int frame_reg; | |
358 | LONGEST frame_offset; | |
359 | unsigned char *buf_end; | |
360 | ||
361 | buf_end = read_sleb128 (data + 1, data + size, &frame_offset); | |
362 | if (buf_end != data + size) | |
363 | error ("Unexpected opcode after DW_OP_fbreg for symbol \"%s\".", | |
364 | SYMBOL_PRINT_NAME (symbol)); | |
4c2df51b | 365 | |
0d53c4c4 DJ |
366 | TARGET_VIRTUAL_FRAME_POINTER (ax->scope, &frame_reg, &frame_offset); |
367 | ax_reg (ax, frame_reg); | |
368 | ax_const_l (ax, frame_offset); | |
369 | ax_simple (ax, aop_add); | |
4c2df51b | 370 | |
0d53c4c4 DJ |
371 | ax_const_l (ax, frame_offset); |
372 | ax_simple (ax, aop_add); | |
373 | value->kind = axs_lvalue_memory; | |
374 | } | |
375 | else | |
376 | error ("Unsupported DWARF opcode in the location of \"%s\".", | |
377 | SYMBOL_PRINT_NAME (symbol)); | |
378 | } | |
4c2df51b DJ |
379 | \f |
380 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression | |
381 | evaluator to calculate the location. */ | |
382 | static struct value * | |
383 | locexpr_read_variable (struct symbol *symbol, struct frame_info *frame) | |
384 | { | |
385 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
386 | struct value *val; | |
387 | val = dwarf2_evaluate_loc_desc (symbol, frame, dlbaton->data, dlbaton->size, | |
388 | dlbaton->objfile); | |
389 | ||
390 | return val; | |
391 | } | |
392 | ||
393 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ | |
394 | static int | |
395 | locexpr_read_needs_frame (struct symbol *symbol) | |
396 | { | |
397 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
398 | return dwarf2_loc_desc_needs_frame (dlbaton->data, dlbaton->size); | |
399 | } | |
400 | ||
401 | /* Print a natural-language description of SYMBOL to STREAM. */ | |
402 | static int | |
403 | locexpr_describe_location (struct symbol *symbol, struct ui_file *stream) | |
404 | { | |
405 | /* FIXME: be more extensive. */ | |
406 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
407 | ||
408 | if (dlbaton->size == 1 | |
409 | && dlbaton->data[0] >= DW_OP_reg0 | |
410 | && dlbaton->data[0] <= DW_OP_reg31) | |
411 | { | |
412 | int regno = DWARF2_REG_TO_REGNUM (dlbaton->data[0] - DW_OP_reg0); | |
413 | fprintf_filtered (stream, | |
414 | "a variable in register %s", REGISTER_NAME (regno)); | |
415 | return 1; | |
416 | } | |
417 | ||
c3228f12 EZ |
418 | /* The location expression for a TLS variable looks like this (on a |
419 | 64-bit LE machine): | |
420 | ||
421 | DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0 | |
422 | (DW_OP_addr: 4; DW_OP_GNU_push_tls_address) | |
423 | ||
424 | 0x3 is the encoding for DW_OP_addr, which has an operand as long | |
425 | as the size of an address on the target machine (here is 8 | |
426 | bytes). 0xe0 is the encoding for DW_OP_GNU_push_tls_address. | |
427 | The operand represents the offset at which the variable is within | |
428 | the thread local storage. */ | |
429 | ||
430 | if (dlbaton->size > 1 | |
431 | && dlbaton->data[dlbaton->size - 1] == DW_OP_GNU_push_tls_address) | |
432 | if (dlbaton->data[0] == DW_OP_addr) | |
433 | { | |
434 | int bytes_read; | |
435 | CORE_ADDR offset = dwarf2_read_address (&dlbaton->data[1], | |
c193f044 | 436 | &dlbaton->data[dlbaton->size - 1], |
c3228f12 EZ |
437 | &bytes_read); |
438 | fprintf_filtered (stream, | |
32ffcbed | 439 | "a thread-local variable at offset %s in the " |
c3228f12 EZ |
440 | "thread-local storage for `%s'", |
441 | paddr_nz (offset), dlbaton->objfile->name); | |
442 | return 1; | |
443 | } | |
444 | ||
445 | ||
4c2df51b DJ |
446 | fprintf_filtered (stream, |
447 | "a variable with complex or multiple locations (DWARF2)"); | |
448 | return 1; | |
449 | } | |
450 | ||
a55cc764 DJ |
451 | |
452 | /* Describe the location of SYMBOL as an agent value in VALUE, generating | |
453 | any necessary bytecode in AX. | |
454 | ||
455 | NOTE drow/2003-02-26: This function is extremely minimal, because | |
456 | doing it correctly is extremely complicated and there is no | |
457 | publicly available stub with tracepoint support for me to test | |
458 | against. When there is one this function should be revisited. */ | |
459 | ||
0d53c4c4 | 460 | static void |
a55cc764 DJ |
461 | locexpr_tracepoint_var_ref (struct symbol * symbol, struct agent_expr * ax, |
462 | struct axs_value * value) | |
463 | { | |
464 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
465 | ||
0d53c4c4 | 466 | dwarf2_tracepoint_var_ref (symbol, ax, value, dlbaton->data, dlbaton->size); |
a55cc764 DJ |
467 | } |
468 | ||
4c2df51b DJ |
469 | /* The set of location functions used with the DWARF-2 expression |
470 | evaluator. */ | |
a67af2b9 | 471 | const struct symbol_ops dwarf2_locexpr_funcs = { |
4c2df51b DJ |
472 | locexpr_read_variable, |
473 | locexpr_read_needs_frame, | |
474 | locexpr_describe_location, | |
a55cc764 | 475 | locexpr_tracepoint_var_ref |
4c2df51b | 476 | }; |
0d53c4c4 DJ |
477 | |
478 | ||
479 | /* Wrapper functions for location lists. These generally find | |
480 | the appropriate location expression and call something above. */ | |
481 | ||
482 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression | |
483 | evaluator to calculate the location. */ | |
484 | static struct value * | |
485 | loclist_read_variable (struct symbol *symbol, struct frame_info *frame) | |
486 | { | |
487 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
488 | struct value *val; | |
489 | unsigned char *data; | |
b6b08ebf | 490 | size_t size; |
0d53c4c4 DJ |
491 | |
492 | data = find_location_expression (dlbaton, &size, | |
493 | frame ? get_frame_pc (frame) : 0); | |
494 | if (data == NULL) | |
495 | error ("Variable \"%s\" is not available.", SYMBOL_NATURAL_NAME (symbol)); | |
496 | ||
497 | val = dwarf2_evaluate_loc_desc (symbol, frame, data, size, dlbaton->objfile); | |
498 | ||
499 | return val; | |
500 | } | |
501 | ||
502 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ | |
503 | static int | |
504 | loclist_read_needs_frame (struct symbol *symbol) | |
505 | { | |
506 | /* If there's a location list, then assume we need to have a frame | |
507 | to choose the appropriate location expression. With tracking of | |
508 | global variables this is not necessarily true, but such tracking | |
509 | is disabled in GCC at the moment until we figure out how to | |
510 | represent it. */ | |
511 | ||
512 | return 1; | |
513 | } | |
514 | ||
515 | /* Print a natural-language description of SYMBOL to STREAM. */ | |
516 | static int | |
517 | loclist_describe_location (struct symbol *symbol, struct ui_file *stream) | |
518 | { | |
519 | /* FIXME: Could print the entire list of locations. */ | |
520 | fprintf_filtered (stream, "a variable with multiple locations"); | |
521 | return 1; | |
522 | } | |
523 | ||
524 | /* Describe the location of SYMBOL as an agent value in VALUE, generating | |
525 | any necessary bytecode in AX. */ | |
526 | static void | |
527 | loclist_tracepoint_var_ref (struct symbol * symbol, struct agent_expr * ax, | |
528 | struct axs_value * value) | |
529 | { | |
530 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
531 | unsigned char *data; | |
b6b08ebf | 532 | size_t size; |
0d53c4c4 DJ |
533 | |
534 | data = find_location_expression (dlbaton, &size, ax->scope); | |
535 | if (data == NULL) | |
536 | error ("Variable \"%s\" is not available.", SYMBOL_NATURAL_NAME (symbol)); | |
537 | ||
538 | dwarf2_tracepoint_var_ref (symbol, ax, value, data, size); | |
539 | } | |
540 | ||
541 | /* The set of location functions used with the DWARF-2 expression | |
542 | evaluator and location lists. */ | |
a67af2b9 | 543 | const struct symbol_ops dwarf2_loclist_funcs = { |
0d53c4c4 DJ |
544 | loclist_read_variable, |
545 | loclist_read_needs_frame, | |
546 | loclist_describe_location, | |
547 | loclist_tracepoint_var_ref | |
548 | }; |