Commit | Line | Data |
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4c2df51b | 1 | /* DWARF 2 location expression support for GDB. |
feb13ab0 | 2 | |
4c38e0a4 JB |
3 | Copyright (C) 2003, 2005, 2007, 2008, 2009, 2010 |
4 | Free Software Foundation, Inc. | |
feb13ab0 | 5 | |
4c2df51b DJ |
6 | Contributed by Daniel Jacobowitz, MontaVista Software, Inc. |
7 | ||
8 | This file is part of GDB. | |
9 | ||
10 | This program is free software; you can redistribute it and/or modify | |
11 | it under the terms of the GNU General Public License as published by | |
a9762ec7 JB |
12 | the Free Software Foundation; either version 3 of the License, or |
13 | (at your option) any later version. | |
4c2df51b | 14 | |
a9762ec7 JB |
15 | This program is distributed in the hope that it will be useful, |
16 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | GNU General Public License for more details. | |
4c2df51b DJ |
19 | |
20 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
4c2df51b DJ |
22 | |
23 | #include "defs.h" | |
24 | #include "ui-out.h" | |
25 | #include "value.h" | |
26 | #include "frame.h" | |
27 | #include "gdbcore.h" | |
28 | #include "target.h" | |
29 | #include "inferior.h" | |
a55cc764 DJ |
30 | #include "ax.h" |
31 | #include "ax-gdb.h" | |
e4adbba9 | 32 | #include "regcache.h" |
c3228f12 | 33 | #include "objfiles.h" |
93ad78a7 | 34 | #include "exceptions.h" |
edb3359d | 35 | #include "block.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 DJ |
41 | |
42 | #include "gdb_string.h" | |
eff4f95e | 43 | #include "gdb_assert.h" |
4c2df51b | 44 | |
9eae7c52 TT |
45 | extern int dwarf2_always_disassemble; |
46 | ||
0936ad1d SS |
47 | static void |
48 | dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc, | |
0d45f56e | 49 | const gdb_byte **start, size_t *length); |
0936ad1d | 50 | |
0d53c4c4 DJ |
51 | /* A helper function for dealing with location lists. Given a |
52 | symbol baton (BATON) and a pc value (PC), find the appropriate | |
53 | location expression, set *LOCEXPR_LENGTH, and return a pointer | |
54 | to the beginning of the expression. Returns NULL on failure. | |
55 | ||
56 | For now, only return the first matching location expression; there | |
57 | can be more than one in the list. */ | |
58 | ||
947bb88f | 59 | static const gdb_byte * |
0d53c4c4 | 60 | find_location_expression (struct dwarf2_loclist_baton *baton, |
b6b08ebf | 61 | size_t *locexpr_length, CORE_ADDR pc) |
0d53c4c4 | 62 | { |
0d53c4c4 | 63 | CORE_ADDR low, high; |
947bb88f | 64 | const gdb_byte *loc_ptr, *buf_end; |
852483bc | 65 | int length; |
ae0d2f24 | 66 | struct objfile *objfile = dwarf2_per_cu_objfile (baton->per_cu); |
f7fd4728 | 67 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
e17a4113 | 68 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
ae0d2f24 | 69 | unsigned int addr_size = dwarf2_per_cu_addr_size (baton->per_cu); |
0d53c4c4 | 70 | CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1)); |
8edfa926 | 71 | /* Adjust base_address for relocatable objects. */ |
ae0d2f24 UW |
72 | CORE_ADDR base_offset = ANOFFSET (objfile->section_offsets, |
73 | SECT_OFF_TEXT (objfile)); | |
8edfa926 | 74 | CORE_ADDR base_address = baton->base_address + base_offset; |
0d53c4c4 DJ |
75 | |
76 | loc_ptr = baton->data; | |
77 | buf_end = baton->data + baton->size; | |
78 | ||
79 | while (1) | |
80 | { | |
b5758fe4 UW |
81 | if (buf_end - loc_ptr < 2 * addr_size) |
82 | error (_("find_location_expression: Corrupted DWARF expression.")); | |
0d53c4c4 | 83 | |
b5758fe4 UW |
84 | low = extract_unsigned_integer (loc_ptr, addr_size, byte_order); |
85 | loc_ptr += addr_size; | |
0d53c4c4 DJ |
86 | |
87 | /* A base-address-selection entry. */ | |
b5758fe4 | 88 | if (low == base_mask) |
0d53c4c4 | 89 | { |
b5758fe4 UW |
90 | base_address = dwarf2_read_address (gdbarch, |
91 | loc_ptr, buf_end, addr_size); | |
92 | loc_ptr += addr_size; | |
0d53c4c4 DJ |
93 | continue; |
94 | } | |
95 | ||
b5758fe4 UW |
96 | high = extract_unsigned_integer (loc_ptr, addr_size, byte_order); |
97 | loc_ptr += addr_size; | |
98 | ||
99 | /* An end-of-list entry. */ | |
100 | if (low == 0 && high == 0) | |
101 | return NULL; | |
102 | ||
0d53c4c4 DJ |
103 | /* Otherwise, a location expression entry. */ |
104 | low += base_address; | |
105 | high += base_address; | |
106 | ||
e17a4113 | 107 | length = extract_unsigned_integer (loc_ptr, 2, byte_order); |
0d53c4c4 DJ |
108 | loc_ptr += 2; |
109 | ||
110 | if (pc >= low && pc < high) | |
111 | { | |
112 | *locexpr_length = length; | |
113 | return loc_ptr; | |
114 | } | |
115 | ||
116 | loc_ptr += length; | |
117 | } | |
118 | } | |
119 | ||
4c2df51b DJ |
120 | /* This is the baton used when performing dwarf2 expression |
121 | evaluation. */ | |
122 | struct dwarf_expr_baton | |
123 | { | |
124 | struct frame_info *frame; | |
17ea53c3 | 125 | struct dwarf2_per_cu_data *per_cu; |
4c2df51b DJ |
126 | }; |
127 | ||
128 | /* Helper functions for dwarf2_evaluate_loc_desc. */ | |
129 | ||
4bc9efe1 | 130 | /* Using the frame specified in BATON, return the value of register |
0b2b0195 | 131 | REGNUM, treated as a pointer. */ |
4c2df51b | 132 | static CORE_ADDR |
61fbb938 | 133 | dwarf_expr_read_reg (void *baton, int dwarf_regnum) |
4c2df51b | 134 | { |
4c2df51b | 135 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
5e2b427d | 136 | struct gdbarch *gdbarch = get_frame_arch (debaton->frame); |
e5192dd8 | 137 | CORE_ADDR result; |
0b2b0195 | 138 | int regnum; |
e4adbba9 | 139 | |
5e2b427d UW |
140 | regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_regnum); |
141 | result = address_from_register (builtin_type (gdbarch)->builtin_data_ptr, | |
0b2b0195 | 142 | regnum, debaton->frame); |
4c2df51b DJ |
143 | return result; |
144 | } | |
145 | ||
146 | /* Read memory at ADDR (length LEN) into BUF. */ | |
147 | ||
148 | static void | |
852483bc | 149 | dwarf_expr_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
4c2df51b DJ |
150 | { |
151 | read_memory (addr, buf, len); | |
152 | } | |
153 | ||
154 | /* Using the frame specified in BATON, find the location expression | |
155 | describing the frame base. Return a pointer to it in START and | |
156 | its length in LENGTH. */ | |
157 | static void | |
0d45f56e | 158 | dwarf_expr_frame_base (void *baton, const gdb_byte **start, size_t * length) |
4c2df51b | 159 | { |
da62e633 AC |
160 | /* FIXME: cagney/2003-03-26: This code should be using |
161 | get_frame_base_address(), and then implement a dwarf2 specific | |
162 | this_base method. */ | |
4c2df51b | 163 | struct symbol *framefunc; |
4c2df51b | 164 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; |
0d53c4c4 | 165 | |
edb3359d DJ |
166 | /* Use block_linkage_function, which returns a real (not inlined) |
167 | function, instead of get_frame_function, which may return an | |
168 | inlined function. */ | |
169 | framefunc = block_linkage_function (get_frame_block (debaton->frame, NULL)); | |
0d53c4c4 | 170 | |
eff4f95e JG |
171 | /* If we found a frame-relative symbol then it was certainly within |
172 | some function associated with a frame. If we can't find the frame, | |
173 | something has gone wrong. */ | |
174 | gdb_assert (framefunc != NULL); | |
175 | ||
0936ad1d SS |
176 | dwarf_expr_frame_base_1 (framefunc, |
177 | get_frame_address_in_block (debaton->frame), | |
178 | start, length); | |
179 | } | |
180 | ||
181 | static void | |
182 | dwarf_expr_frame_base_1 (struct symbol *framefunc, CORE_ADDR pc, | |
0d45f56e | 183 | const gdb_byte **start, size_t *length) |
0936ad1d | 184 | { |
edb3359d DJ |
185 | if (SYMBOL_LOCATION_BATON (framefunc) == NULL) |
186 | *start = NULL; | |
187 | else if (SYMBOL_COMPUTED_OPS (framefunc) == &dwarf2_loclist_funcs) | |
0d53c4c4 DJ |
188 | { |
189 | struct dwarf2_loclist_baton *symbaton; | |
22c6caba | 190 | |
0d53c4c4 | 191 | symbaton = SYMBOL_LOCATION_BATON (framefunc); |
0936ad1d | 192 | *start = find_location_expression (symbaton, length, pc); |
0d53c4c4 DJ |
193 | } |
194 | else | |
195 | { | |
196 | struct dwarf2_locexpr_baton *symbaton; | |
9a619af0 | 197 | |
0d53c4c4 | 198 | symbaton = SYMBOL_LOCATION_BATON (framefunc); |
ebd3bcc1 JK |
199 | if (symbaton != NULL) |
200 | { | |
201 | *length = symbaton->size; | |
202 | *start = symbaton->data; | |
203 | } | |
204 | else | |
205 | *start = NULL; | |
0d53c4c4 DJ |
206 | } |
207 | ||
208 | if (*start == NULL) | |
8a3fe4f8 | 209 | error (_("Could not find the frame base for \"%s\"."), |
0d53c4c4 | 210 | SYMBOL_NATURAL_NAME (framefunc)); |
4c2df51b DJ |
211 | } |
212 | ||
e7802207 TT |
213 | /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for |
214 | the frame in BATON. */ | |
215 | ||
216 | static CORE_ADDR | |
217 | dwarf_expr_frame_cfa (void *baton) | |
218 | { | |
219 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
9a619af0 | 220 | |
e7802207 TT |
221 | return dwarf2_frame_cfa (debaton->frame); |
222 | } | |
223 | ||
4c2df51b DJ |
224 | /* Using the objfile specified in BATON, find the address for the |
225 | current thread's thread-local storage with offset OFFSET. */ | |
226 | static CORE_ADDR | |
227 | dwarf_expr_tls_address (void *baton, CORE_ADDR offset) | |
228 | { | |
229 | struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton; | |
17ea53c3 | 230 | struct objfile *objfile = dwarf2_per_cu_objfile (debaton->per_cu); |
4c2df51b | 231 | |
17ea53c3 | 232 | return target_translate_tls_address (objfile, offset); |
4c2df51b DJ |
233 | } |
234 | ||
5c631832 JK |
235 | /* Call DWARF subroutine from DW_AT_location of DIE at DIE_OFFSET in current CU |
236 | (as is PER_CU). State of the CTX is not affected by the call and return. */ | |
237 | ||
238 | static void | |
239 | per_cu_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset, | |
240 | struct dwarf2_per_cu_data *per_cu) | |
241 | { | |
242 | struct dwarf2_locexpr_baton block; | |
243 | ||
244 | block = dwarf2_fetch_die_location_block (die_offset, per_cu); | |
245 | ||
246 | /* DW_OP_call_ref is currently not supported. */ | |
247 | gdb_assert (block.per_cu == per_cu); | |
248 | ||
249 | dwarf_expr_eval (ctx, block.data, block.size); | |
250 | } | |
251 | ||
252 | /* Helper interface of per_cu_dwarf_call for dwarf2_evaluate_loc_desc. */ | |
253 | ||
254 | static void | |
255 | dwarf_expr_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset) | |
256 | { | |
257 | struct dwarf_expr_baton *debaton = ctx->baton; | |
258 | ||
259 | return per_cu_dwarf_call (ctx, die_offset, debaton->per_cu); | |
260 | } | |
261 | ||
052b9502 NF |
262 | struct piece_closure |
263 | { | |
88bfdde4 TT |
264 | /* Reference count. */ |
265 | int refc; | |
266 | ||
052b9502 NF |
267 | /* The number of pieces used to describe this variable. */ |
268 | int n_pieces; | |
269 | ||
6063c216 UW |
270 | /* The target address size, used only for DWARF_VALUE_STACK. */ |
271 | int addr_size; | |
cec03d70 | 272 | |
052b9502 NF |
273 | /* The pieces themselves. */ |
274 | struct dwarf_expr_piece *pieces; | |
275 | }; | |
276 | ||
277 | /* Allocate a closure for a value formed from separately-described | |
278 | PIECES. */ | |
279 | ||
280 | static struct piece_closure * | |
cec03d70 | 281 | allocate_piece_closure (int n_pieces, struct dwarf_expr_piece *pieces, |
6063c216 | 282 | int addr_size) |
052b9502 NF |
283 | { |
284 | struct piece_closure *c = XZALLOC (struct piece_closure); | |
285 | ||
88bfdde4 | 286 | c->refc = 1; |
052b9502 | 287 | c->n_pieces = n_pieces; |
6063c216 | 288 | c->addr_size = addr_size; |
052b9502 NF |
289 | c->pieces = XCALLOC (n_pieces, struct dwarf_expr_piece); |
290 | ||
291 | memcpy (c->pieces, pieces, n_pieces * sizeof (struct dwarf_expr_piece)); | |
292 | ||
293 | return c; | |
294 | } | |
295 | ||
d3b1e874 TT |
296 | /* The lowest-level function to extract bits from a byte buffer. |
297 | SOURCE is the buffer. It is updated if we read to the end of a | |
298 | byte. | |
299 | SOURCE_OFFSET_BITS is the offset of the first bit to read. It is | |
300 | updated to reflect the number of bits actually read. | |
301 | NBITS is the number of bits we want to read. It is updated to | |
302 | reflect the number of bits actually read. This function may read | |
303 | fewer bits. | |
304 | BITS_BIG_ENDIAN is taken directly from gdbarch. | |
305 | This function returns the extracted bits. */ | |
306 | ||
307 | static unsigned int | |
308 | extract_bits_primitive (const gdb_byte **source, | |
309 | unsigned int *source_offset_bits, | |
310 | int *nbits, int bits_big_endian) | |
311 | { | |
312 | unsigned int avail, mask, datum; | |
313 | ||
314 | gdb_assert (*source_offset_bits < 8); | |
315 | ||
316 | avail = 8 - *source_offset_bits; | |
317 | if (avail > *nbits) | |
318 | avail = *nbits; | |
319 | ||
320 | mask = (1 << avail) - 1; | |
321 | datum = **source; | |
322 | if (bits_big_endian) | |
323 | datum >>= 8 - (*source_offset_bits + *nbits); | |
324 | else | |
325 | datum >>= *source_offset_bits; | |
326 | datum &= mask; | |
327 | ||
328 | *nbits -= avail; | |
329 | *source_offset_bits += avail; | |
330 | if (*source_offset_bits >= 8) | |
331 | { | |
332 | *source_offset_bits -= 8; | |
333 | ++*source; | |
334 | } | |
335 | ||
336 | return datum; | |
337 | } | |
338 | ||
339 | /* Extract some bits from a source buffer and move forward in the | |
340 | buffer. | |
341 | ||
342 | SOURCE is the source buffer. It is updated as bytes are read. | |
343 | SOURCE_OFFSET_BITS is the offset into SOURCE. It is updated as | |
344 | bits are read. | |
345 | NBITS is the number of bits to read. | |
346 | BITS_BIG_ENDIAN is taken directly from gdbarch. | |
347 | ||
348 | This function returns the bits that were read. */ | |
349 | ||
350 | static unsigned int | |
351 | extract_bits (const gdb_byte **source, unsigned int *source_offset_bits, | |
352 | int nbits, int bits_big_endian) | |
353 | { | |
354 | unsigned int datum; | |
355 | ||
356 | gdb_assert (nbits > 0 && nbits <= 8); | |
357 | ||
358 | datum = extract_bits_primitive (source, source_offset_bits, &nbits, | |
359 | bits_big_endian); | |
360 | if (nbits > 0) | |
361 | { | |
362 | unsigned int more; | |
363 | ||
364 | more = extract_bits_primitive (source, source_offset_bits, &nbits, | |
365 | bits_big_endian); | |
366 | if (bits_big_endian) | |
367 | datum <<= nbits; | |
368 | else | |
369 | more <<= nbits; | |
370 | datum |= more; | |
371 | } | |
372 | ||
373 | return datum; | |
374 | } | |
375 | ||
376 | /* Write some bits into a buffer and move forward in the buffer. | |
377 | ||
378 | DATUM is the bits to write. The low-order bits of DATUM are used. | |
379 | DEST is the destination buffer. It is updated as bytes are | |
380 | written. | |
381 | DEST_OFFSET_BITS is the bit offset in DEST at which writing is | |
382 | done. | |
383 | NBITS is the number of valid bits in DATUM. | |
384 | BITS_BIG_ENDIAN is taken directly from gdbarch. */ | |
385 | ||
386 | static void | |
387 | insert_bits (unsigned int datum, | |
388 | gdb_byte *dest, unsigned int dest_offset_bits, | |
389 | int nbits, int bits_big_endian) | |
390 | { | |
391 | unsigned int mask; | |
392 | ||
393 | gdb_assert (dest_offset_bits >= 0 && dest_offset_bits + nbits <= 8); | |
394 | ||
395 | mask = (1 << nbits) - 1; | |
396 | if (bits_big_endian) | |
397 | { | |
398 | datum <<= 8 - (dest_offset_bits + nbits); | |
399 | mask <<= 8 - (dest_offset_bits + nbits); | |
400 | } | |
401 | else | |
402 | { | |
403 | datum <<= dest_offset_bits; | |
404 | mask <<= dest_offset_bits; | |
405 | } | |
406 | ||
407 | gdb_assert ((datum & ~mask) == 0); | |
408 | ||
409 | *dest = (*dest & ~mask) | datum; | |
410 | } | |
411 | ||
412 | /* Copy bits from a source to a destination. | |
413 | ||
414 | DEST is where the bits should be written. | |
415 | DEST_OFFSET_BITS is the bit offset into DEST. | |
416 | SOURCE is the source of bits. | |
417 | SOURCE_OFFSET_BITS is the bit offset into SOURCE. | |
418 | BIT_COUNT is the number of bits to copy. | |
419 | BITS_BIG_ENDIAN is taken directly from gdbarch. */ | |
420 | ||
421 | static void | |
422 | copy_bitwise (gdb_byte *dest, unsigned int dest_offset_bits, | |
423 | const gdb_byte *source, unsigned int source_offset_bits, | |
424 | unsigned int bit_count, | |
425 | int bits_big_endian) | |
426 | { | |
427 | unsigned int dest_avail; | |
428 | int datum; | |
429 | ||
430 | /* Reduce everything to byte-size pieces. */ | |
431 | dest += dest_offset_bits / 8; | |
432 | dest_offset_bits %= 8; | |
433 | source += source_offset_bits / 8; | |
434 | source_offset_bits %= 8; | |
435 | ||
436 | dest_avail = 8 - dest_offset_bits % 8; | |
437 | ||
438 | /* See if we can fill the first destination byte. */ | |
439 | if (dest_avail < bit_count) | |
440 | { | |
441 | datum = extract_bits (&source, &source_offset_bits, dest_avail, | |
442 | bits_big_endian); | |
443 | insert_bits (datum, dest, dest_offset_bits, dest_avail, bits_big_endian); | |
444 | ++dest; | |
445 | dest_offset_bits = 0; | |
446 | bit_count -= dest_avail; | |
447 | } | |
448 | ||
449 | /* Now, either DEST_OFFSET_BITS is byte-aligned, or we have fewer | |
450 | than 8 bits remaining. */ | |
451 | gdb_assert (dest_offset_bits % 8 == 0 || bit_count < 8); | |
452 | for (; bit_count >= 8; bit_count -= 8) | |
453 | { | |
454 | datum = extract_bits (&source, &source_offset_bits, 8, bits_big_endian); | |
455 | *dest++ = (gdb_byte) datum; | |
456 | } | |
457 | ||
458 | /* Finally, we may have a few leftover bits. */ | |
459 | gdb_assert (bit_count <= 8 - dest_offset_bits % 8); | |
460 | if (bit_count > 0) | |
461 | { | |
462 | datum = extract_bits (&source, &source_offset_bits, bit_count, | |
463 | bits_big_endian); | |
464 | insert_bits (datum, dest, dest_offset_bits, bit_count, bits_big_endian); | |
465 | } | |
466 | } | |
467 | ||
052b9502 NF |
468 | static void |
469 | read_pieced_value (struct value *v) | |
470 | { | |
471 | int i; | |
472 | long offset = 0; | |
d3b1e874 | 473 | ULONGEST bits_to_skip; |
052b9502 NF |
474 | gdb_byte *contents; |
475 | struct piece_closure *c = (struct piece_closure *) value_computed_closure (v); | |
476 | struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (v)); | |
afd74c5f | 477 | size_t type_len; |
d3b1e874 TT |
478 | size_t buffer_size = 0; |
479 | char *buffer = NULL; | |
480 | struct cleanup *cleanup; | |
481 | int bits_big_endian | |
482 | = gdbarch_bits_big_endian (get_type_arch (value_type (v))); | |
afd74c5f TT |
483 | |
484 | if (value_type (v) != value_enclosing_type (v)) | |
485 | internal_error (__FILE__, __LINE__, | |
486 | _("Should not be able to create a lazy value with " | |
487 | "an enclosing type")); | |
052b9502 | 488 | |
d3b1e874 TT |
489 | cleanup = make_cleanup (free_current_contents, &buffer); |
490 | ||
052b9502 | 491 | contents = value_contents_raw (v); |
d3b1e874 TT |
492 | bits_to_skip = 8 * value_offset (v); |
493 | type_len = 8 * TYPE_LENGTH (value_type (v)); | |
494 | ||
afd74c5f | 495 | for (i = 0; i < c->n_pieces && offset < type_len; i++) |
052b9502 NF |
496 | { |
497 | struct dwarf_expr_piece *p = &c->pieces[i]; | |
d3b1e874 TT |
498 | size_t this_size, this_size_bits; |
499 | long dest_offset_bits, source_offset_bits, source_offset; | |
0d45f56e | 500 | const gdb_byte *intermediate_buffer; |
d3b1e874 TT |
501 | |
502 | /* Compute size, source, and destination offsets for copying, in | |
503 | bits. */ | |
504 | this_size_bits = p->size; | |
505 | if (bits_to_skip > 0 && bits_to_skip >= this_size_bits) | |
afd74c5f | 506 | { |
d3b1e874 | 507 | bits_to_skip -= this_size_bits; |
afd74c5f TT |
508 | continue; |
509 | } | |
d3b1e874 TT |
510 | if (this_size_bits > type_len - offset) |
511 | this_size_bits = type_len - offset; | |
512 | if (bits_to_skip > 0) | |
afd74c5f | 513 | { |
d3b1e874 TT |
514 | dest_offset_bits = 0; |
515 | source_offset_bits = bits_to_skip; | |
516 | this_size_bits -= bits_to_skip; | |
517 | bits_to_skip = 0; | |
afd74c5f TT |
518 | } |
519 | else | |
520 | { | |
d3b1e874 TT |
521 | dest_offset_bits = offset; |
522 | source_offset_bits = 0; | |
afd74c5f | 523 | } |
9a619af0 | 524 | |
d3b1e874 TT |
525 | this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8; |
526 | source_offset = source_offset_bits / 8; | |
527 | if (buffer_size < this_size) | |
528 | { | |
529 | buffer_size = this_size; | |
530 | buffer = xrealloc (buffer, buffer_size); | |
531 | } | |
532 | intermediate_buffer = buffer; | |
533 | ||
534 | /* Copy from the source to DEST_BUFFER. */ | |
cec03d70 | 535 | switch (p->location) |
052b9502 | 536 | { |
cec03d70 TT |
537 | case DWARF_VALUE_REGISTER: |
538 | { | |
539 | struct gdbarch *arch = get_frame_arch (frame); | |
cec03d70 | 540 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, |
44353522 | 541 | p->v.expr.value); |
afd74c5f | 542 | int reg_offset = source_offset; |
dcbf108f UW |
543 | |
544 | if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG | |
afd74c5f | 545 | && this_size < register_size (arch, gdb_regnum)) |
d3b1e874 TT |
546 | { |
547 | /* Big-endian, and we want less than full size. */ | |
548 | reg_offset = register_size (arch, gdb_regnum) - this_size; | |
549 | /* We want the lower-order THIS_SIZE_BITS of the bytes | |
550 | we extract from the register. */ | |
551 | source_offset_bits += 8 * this_size - this_size_bits; | |
552 | } | |
dcbf108f | 553 | |
63b4f126 MGD |
554 | if (gdb_regnum != -1) |
555 | { | |
556 | get_frame_register_bytes (frame, gdb_regnum, reg_offset, | |
d3b1e874 | 557 | this_size, buffer); |
63b4f126 MGD |
558 | } |
559 | else | |
560 | { | |
561 | error (_("Unable to access DWARF register number %s"), | |
562 | paddress (arch, p->v.expr.value)); | |
563 | } | |
cec03d70 TT |
564 | } |
565 | break; | |
566 | ||
567 | case DWARF_VALUE_MEMORY: | |
44353522 | 568 | if (p->v.expr.in_stack_memory) |
d3b1e874 | 569 | read_stack (p->v.expr.value + source_offset, buffer, this_size); |
44353522 | 570 | else |
d3b1e874 | 571 | read_memory (p->v.expr.value + source_offset, buffer, this_size); |
cec03d70 TT |
572 | break; |
573 | ||
574 | case DWARF_VALUE_STACK: | |
575 | { | |
6063c216 | 576 | struct gdbarch *gdbarch = get_type_arch (value_type (v)); |
afd74c5f | 577 | size_t n = this_size; |
9a619af0 | 578 | |
afd74c5f TT |
579 | if (n > c->addr_size - source_offset) |
580 | n = (c->addr_size >= source_offset | |
581 | ? c->addr_size - source_offset | |
582 | : 0); | |
583 | if (n == 0) | |
584 | { | |
585 | /* Nothing. */ | |
586 | } | |
587 | else if (source_offset == 0) | |
d3b1e874 | 588 | store_unsigned_integer (buffer, n, |
afd74c5f TT |
589 | gdbarch_byte_order (gdbarch), |
590 | p->v.expr.value); | |
591 | else | |
592 | { | |
593 | gdb_byte bytes[sizeof (ULONGEST)]; | |
594 | ||
595 | store_unsigned_integer (bytes, n + source_offset, | |
596 | gdbarch_byte_order (gdbarch), | |
597 | p->v.expr.value); | |
d3b1e874 | 598 | memcpy (buffer, bytes + source_offset, n); |
afd74c5f | 599 | } |
cec03d70 TT |
600 | } |
601 | break; | |
602 | ||
603 | case DWARF_VALUE_LITERAL: | |
604 | { | |
afd74c5f TT |
605 | size_t n = this_size; |
606 | ||
607 | if (n > p->v.literal.length - source_offset) | |
608 | n = (p->v.literal.length >= source_offset | |
609 | ? p->v.literal.length - source_offset | |
610 | : 0); | |
611 | if (n != 0) | |
d3b1e874 | 612 | intermediate_buffer = p->v.literal.data + source_offset; |
cec03d70 TT |
613 | } |
614 | break; | |
615 | ||
cb826367 TT |
616 | case DWARF_VALUE_OPTIMIZED_OUT: |
617 | /* We just leave the bits empty for now. This is not ideal | |
618 | but gdb currently does not have a nice way to represent | |
619 | optimized-out pieces. */ | |
d3b1e874 | 620 | warning (_("bits %ld-%ld in computed object were optimized out; " |
cb826367 TT |
621 | "replacing with zeroes"), |
622 | offset, | |
d3b1e874 | 623 | offset + (long) this_size_bits); |
cb826367 TT |
624 | break; |
625 | ||
cec03d70 TT |
626 | default: |
627 | internal_error (__FILE__, __LINE__, _("invalid location type")); | |
052b9502 | 628 | } |
d3b1e874 TT |
629 | |
630 | if (p->location != DWARF_VALUE_OPTIMIZED_OUT) | |
631 | copy_bitwise (contents, dest_offset_bits, | |
632 | intermediate_buffer, source_offset_bits % 8, | |
633 | this_size_bits, bits_big_endian); | |
634 | ||
635 | offset += this_size_bits; | |
052b9502 | 636 | } |
d3b1e874 TT |
637 | |
638 | do_cleanups (cleanup); | |
052b9502 NF |
639 | } |
640 | ||
641 | static void | |
642 | write_pieced_value (struct value *to, struct value *from) | |
643 | { | |
644 | int i; | |
645 | long offset = 0; | |
d3b1e874 | 646 | ULONGEST bits_to_skip; |
afd74c5f | 647 | const gdb_byte *contents; |
052b9502 NF |
648 | struct piece_closure *c = (struct piece_closure *) value_computed_closure (to); |
649 | struct frame_info *frame = frame_find_by_id (VALUE_FRAME_ID (to)); | |
afd74c5f | 650 | size_t type_len; |
d3b1e874 TT |
651 | size_t buffer_size = 0; |
652 | char *buffer = NULL; | |
653 | struct cleanup *cleanup; | |
654 | int bits_big_endian | |
655 | = gdbarch_bits_big_endian (get_type_arch (value_type (to))); | |
052b9502 NF |
656 | |
657 | if (frame == NULL) | |
658 | { | |
659 | set_value_optimized_out (to, 1); | |
660 | return; | |
661 | } | |
662 | ||
d3b1e874 TT |
663 | cleanup = make_cleanup (free_current_contents, &buffer); |
664 | ||
afd74c5f | 665 | contents = value_contents (from); |
d3b1e874 TT |
666 | bits_to_skip = 8 * value_offset (to); |
667 | type_len = 8 * TYPE_LENGTH (value_type (to)); | |
afd74c5f | 668 | for (i = 0; i < c->n_pieces && offset < type_len; i++) |
052b9502 NF |
669 | { |
670 | struct dwarf_expr_piece *p = &c->pieces[i]; | |
d3b1e874 TT |
671 | size_t this_size_bits, this_size; |
672 | long dest_offset_bits, source_offset_bits, dest_offset, source_offset; | |
673 | int need_bitwise; | |
674 | const gdb_byte *source_buffer; | |
afd74c5f | 675 | |
d3b1e874 TT |
676 | this_size_bits = p->size; |
677 | if (bits_to_skip > 0 && bits_to_skip >= this_size_bits) | |
afd74c5f | 678 | { |
d3b1e874 | 679 | bits_to_skip -= this_size_bits; |
afd74c5f TT |
680 | continue; |
681 | } | |
d3b1e874 TT |
682 | if (this_size_bits > type_len - offset) |
683 | this_size_bits = type_len - offset; | |
684 | if (bits_to_skip > 0) | |
afd74c5f | 685 | { |
d3b1e874 TT |
686 | dest_offset_bits = bits_to_skip; |
687 | source_offset_bits = 0; | |
688 | this_size_bits -= bits_to_skip; | |
689 | bits_to_skip = 0; | |
afd74c5f TT |
690 | } |
691 | else | |
692 | { | |
d3b1e874 TT |
693 | dest_offset_bits = 0; |
694 | source_offset_bits = offset; | |
695 | } | |
696 | ||
697 | this_size = (this_size_bits + source_offset_bits % 8 + 7) / 8; | |
698 | source_offset = source_offset_bits / 8; | |
699 | dest_offset = dest_offset_bits / 8; | |
700 | if (dest_offset_bits % 8 == 0 && source_offset_bits % 8 == 0) | |
701 | { | |
702 | source_buffer = contents + source_offset; | |
703 | need_bitwise = 0; | |
704 | } | |
705 | else | |
706 | { | |
707 | if (buffer_size < this_size) | |
708 | { | |
709 | buffer_size = this_size; | |
710 | buffer = xrealloc (buffer, buffer_size); | |
711 | } | |
712 | source_buffer = buffer; | |
713 | need_bitwise = 1; | |
afd74c5f | 714 | } |
9a619af0 | 715 | |
cec03d70 | 716 | switch (p->location) |
052b9502 | 717 | { |
cec03d70 TT |
718 | case DWARF_VALUE_REGISTER: |
719 | { | |
720 | struct gdbarch *arch = get_frame_arch (frame); | |
44353522 | 721 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, p->v.expr.value); |
afd74c5f | 722 | int reg_offset = dest_offset; |
dcbf108f UW |
723 | |
724 | if (gdbarch_byte_order (arch) == BFD_ENDIAN_BIG | |
afd74c5f | 725 | && this_size <= register_size (arch, gdb_regnum)) |
dcbf108f | 726 | /* Big-endian, and we want less than full size. */ |
afd74c5f | 727 | reg_offset = register_size (arch, gdb_regnum) - this_size; |
dcbf108f | 728 | |
63b4f126 MGD |
729 | if (gdb_regnum != -1) |
730 | { | |
d3b1e874 TT |
731 | if (need_bitwise) |
732 | { | |
733 | get_frame_register_bytes (frame, gdb_regnum, reg_offset, | |
734 | this_size, buffer); | |
735 | copy_bitwise (buffer, dest_offset_bits, | |
736 | contents, source_offset_bits, | |
737 | this_size_bits, | |
738 | bits_big_endian); | |
739 | } | |
740 | ||
63b4f126 | 741 | put_frame_register_bytes (frame, gdb_regnum, reg_offset, |
d3b1e874 | 742 | this_size, source_buffer); |
63b4f126 MGD |
743 | } |
744 | else | |
745 | { | |
746 | error (_("Unable to write to DWARF register number %s"), | |
747 | paddress (arch, p->v.expr.value)); | |
748 | } | |
cec03d70 TT |
749 | } |
750 | break; | |
751 | case DWARF_VALUE_MEMORY: | |
d3b1e874 TT |
752 | if (need_bitwise) |
753 | { | |
754 | /* Only the first and last bytes can possibly have any | |
755 | bits reused. */ | |
756 | read_memory (p->v.expr.value + dest_offset, buffer, 1); | |
757 | read_memory (p->v.expr.value + dest_offset + this_size - 1, | |
758 | buffer + this_size - 1, 1); | |
759 | copy_bitwise (buffer, dest_offset_bits, | |
760 | contents, source_offset_bits, | |
761 | this_size_bits, | |
762 | bits_big_endian); | |
763 | } | |
764 | ||
afd74c5f | 765 | write_memory (p->v.expr.value + dest_offset, |
d3b1e874 | 766 | source_buffer, this_size); |
cec03d70 TT |
767 | break; |
768 | default: | |
769 | set_value_optimized_out (to, 1); | |
d3b1e874 | 770 | goto done; |
052b9502 | 771 | } |
d3b1e874 | 772 | offset += this_size_bits; |
052b9502 | 773 | } |
d3b1e874 TT |
774 | |
775 | done: | |
776 | do_cleanups (cleanup); | |
052b9502 NF |
777 | } |
778 | ||
779 | static void * | |
780 | copy_pieced_value_closure (struct value *v) | |
781 | { | |
782 | struct piece_closure *c = (struct piece_closure *) value_computed_closure (v); | |
783 | ||
88bfdde4 TT |
784 | ++c->refc; |
785 | return c; | |
052b9502 NF |
786 | } |
787 | ||
788 | static void | |
789 | free_pieced_value_closure (struct value *v) | |
790 | { | |
791 | struct piece_closure *c = (struct piece_closure *) value_computed_closure (v); | |
792 | ||
88bfdde4 TT |
793 | --c->refc; |
794 | if (c->refc == 0) | |
795 | { | |
796 | xfree (c->pieces); | |
797 | xfree (c); | |
798 | } | |
052b9502 NF |
799 | } |
800 | ||
801 | /* Functions for accessing a variable described by DW_OP_piece. */ | |
802 | static struct lval_funcs pieced_value_funcs = { | |
803 | read_pieced_value, | |
804 | write_pieced_value, | |
805 | copy_pieced_value_closure, | |
806 | free_pieced_value_closure | |
807 | }; | |
808 | ||
4c2df51b | 809 | /* Evaluate a location description, starting at DATA and with length |
a2d33775 | 810 | SIZE, to find the current location of variable of TYPE in the context |
4c2df51b | 811 | of FRAME. */ |
a2d33775 | 812 | |
4c2df51b | 813 | static struct value * |
a2d33775 | 814 | dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame, |
947bb88f | 815 | const gdb_byte *data, unsigned short size, |
ae0d2f24 | 816 | struct dwarf2_per_cu_data *per_cu) |
4c2df51b | 817 | { |
4c2df51b DJ |
818 | struct value *retval; |
819 | struct dwarf_expr_baton baton; | |
820 | struct dwarf_expr_context *ctx; | |
4a227398 | 821 | struct cleanup *old_chain; |
4c2df51b | 822 | |
0d53c4c4 DJ |
823 | if (size == 0) |
824 | { | |
a2d33775 | 825 | retval = allocate_value (type); |
0d53c4c4 | 826 | VALUE_LVAL (retval) = not_lval; |
feb13ab0 | 827 | set_value_optimized_out (retval, 1); |
10fb19b6 | 828 | return retval; |
0d53c4c4 DJ |
829 | } |
830 | ||
4c2df51b | 831 | baton.frame = frame; |
17ea53c3 | 832 | baton.per_cu = per_cu; |
4c2df51b DJ |
833 | |
834 | ctx = new_dwarf_expr_context (); | |
4a227398 TT |
835 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
836 | ||
17ea53c3 | 837 | ctx->gdbarch = get_objfile_arch (dwarf2_per_cu_objfile (per_cu)); |
ae0d2f24 | 838 | ctx->addr_size = dwarf2_per_cu_addr_size (per_cu); |
4c2df51b DJ |
839 | ctx->baton = &baton; |
840 | ctx->read_reg = dwarf_expr_read_reg; | |
841 | ctx->read_mem = dwarf_expr_read_mem; | |
842 | ctx->get_frame_base = dwarf_expr_frame_base; | |
e7802207 | 843 | ctx->get_frame_cfa = dwarf_expr_frame_cfa; |
4c2df51b | 844 | ctx->get_tls_address = dwarf_expr_tls_address; |
5c631832 | 845 | ctx->dwarf_call = dwarf_expr_dwarf_call; |
4c2df51b DJ |
846 | |
847 | dwarf_expr_eval (ctx, data, size); | |
87808bd6 JB |
848 | if (ctx->num_pieces > 0) |
849 | { | |
052b9502 NF |
850 | struct piece_closure *c; |
851 | struct frame_id frame_id = get_frame_id (frame); | |
852 | ||
6063c216 UW |
853 | c = allocate_piece_closure (ctx->num_pieces, ctx->pieces, |
854 | ctx->addr_size); | |
a2d33775 | 855 | retval = allocate_computed_value (type, &pieced_value_funcs, c); |
052b9502 | 856 | VALUE_FRAME_ID (retval) = frame_id; |
87808bd6 | 857 | } |
4c2df51b DJ |
858 | else |
859 | { | |
cec03d70 TT |
860 | switch (ctx->location) |
861 | { | |
862 | case DWARF_VALUE_REGISTER: | |
863 | { | |
864 | struct gdbarch *arch = get_frame_arch (frame); | |
865 | CORE_ADDR dwarf_regnum = dwarf_expr_fetch (ctx, 0); | |
866 | int gdb_regnum = gdbarch_dwarf2_reg_to_regnum (arch, dwarf_regnum); | |
9a619af0 | 867 | |
63b4f126 | 868 | if (gdb_regnum != -1) |
a2d33775 | 869 | retval = value_from_register (type, gdb_regnum, frame); |
63b4f126 | 870 | else |
a2d33775 JK |
871 | error (_("Unable to access DWARF register number %s"), |
872 | paddress (arch, dwarf_regnum)); | |
cec03d70 TT |
873 | } |
874 | break; | |
875 | ||
876 | case DWARF_VALUE_MEMORY: | |
877 | { | |
878 | CORE_ADDR address = dwarf_expr_fetch (ctx, 0); | |
44353522 | 879 | int in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0); |
cec03d70 | 880 | |
a2d33775 | 881 | retval = allocate_value (type); |
cec03d70 TT |
882 | VALUE_LVAL (retval) = lval_memory; |
883 | set_value_lazy (retval, 1); | |
44353522 DE |
884 | if (in_stack_memory) |
885 | set_value_stack (retval, 1); | |
cec03d70 TT |
886 | set_value_address (retval, address); |
887 | } | |
888 | break; | |
889 | ||
890 | case DWARF_VALUE_STACK: | |
891 | { | |
cec03d70 TT |
892 | ULONGEST value = (ULONGEST) dwarf_expr_fetch (ctx, 0); |
893 | bfd_byte *contents; | |
894 | size_t n = ctx->addr_size; | |
895 | ||
a2d33775 | 896 | retval = allocate_value (type); |
cec03d70 | 897 | contents = value_contents_raw (retval); |
a2d33775 JK |
898 | if (n > TYPE_LENGTH (type)) |
899 | n = TYPE_LENGTH (type); | |
05566b3b TT |
900 | store_unsigned_integer (contents, n, |
901 | gdbarch_byte_order (ctx->gdbarch), | |
902 | value); | |
cec03d70 TT |
903 | } |
904 | break; | |
905 | ||
906 | case DWARF_VALUE_LITERAL: | |
907 | { | |
908 | bfd_byte *contents; | |
909 | size_t n = ctx->len; | |
910 | ||
a2d33775 | 911 | retval = allocate_value (type); |
cec03d70 | 912 | contents = value_contents_raw (retval); |
a2d33775 JK |
913 | if (n > TYPE_LENGTH (type)) |
914 | n = TYPE_LENGTH (type); | |
cec03d70 TT |
915 | memcpy (contents, ctx->data, n); |
916 | } | |
917 | break; | |
918 | ||
cb826367 TT |
919 | /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context -- |
920 | it can only be encountered when making a piece. */ | |
921 | case DWARF_VALUE_OPTIMIZED_OUT: | |
cec03d70 TT |
922 | default: |
923 | internal_error (__FILE__, __LINE__, _("invalid location type")); | |
924 | } | |
4c2df51b DJ |
925 | } |
926 | ||
42be36b3 CT |
927 | set_value_initialized (retval, ctx->initialized); |
928 | ||
4a227398 | 929 | do_cleanups (old_chain); |
4c2df51b DJ |
930 | |
931 | return retval; | |
932 | } | |
4c2df51b DJ |
933 | \f |
934 | /* Helper functions and baton for dwarf2_loc_desc_needs_frame. */ | |
935 | ||
936 | struct needs_frame_baton | |
937 | { | |
938 | int needs_frame; | |
17ea53c3 | 939 | struct dwarf2_per_cu_data *per_cu; |
4c2df51b DJ |
940 | }; |
941 | ||
942 | /* Reads from registers do require a frame. */ | |
943 | static CORE_ADDR | |
61fbb938 | 944 | needs_frame_read_reg (void *baton, int regnum) |
4c2df51b DJ |
945 | { |
946 | struct needs_frame_baton *nf_baton = baton; | |
9a619af0 | 947 | |
4c2df51b DJ |
948 | nf_baton->needs_frame = 1; |
949 | return 1; | |
950 | } | |
951 | ||
952 | /* Reads from memory do not require a frame. */ | |
953 | static void | |
852483bc | 954 | needs_frame_read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
4c2df51b DJ |
955 | { |
956 | memset (buf, 0, len); | |
957 | } | |
958 | ||
959 | /* Frame-relative accesses do require a frame. */ | |
960 | static void | |
0d45f56e | 961 | needs_frame_frame_base (void *baton, const gdb_byte **start, size_t * length) |
4c2df51b | 962 | { |
852483bc | 963 | static gdb_byte lit0 = DW_OP_lit0; |
4c2df51b DJ |
964 | struct needs_frame_baton *nf_baton = baton; |
965 | ||
966 | *start = &lit0; | |
967 | *length = 1; | |
968 | ||
969 | nf_baton->needs_frame = 1; | |
970 | } | |
971 | ||
e7802207 TT |
972 | /* CFA accesses require a frame. */ |
973 | ||
974 | static CORE_ADDR | |
975 | needs_frame_frame_cfa (void *baton) | |
976 | { | |
977 | struct needs_frame_baton *nf_baton = baton; | |
9a619af0 | 978 | |
e7802207 TT |
979 | nf_baton->needs_frame = 1; |
980 | return 1; | |
981 | } | |
982 | ||
4c2df51b DJ |
983 | /* Thread-local accesses do require a frame. */ |
984 | static CORE_ADDR | |
985 | needs_frame_tls_address (void *baton, CORE_ADDR offset) | |
986 | { | |
987 | struct needs_frame_baton *nf_baton = baton; | |
9a619af0 | 988 | |
4c2df51b DJ |
989 | nf_baton->needs_frame = 1; |
990 | return 1; | |
991 | } | |
992 | ||
5c631832 JK |
993 | /* Helper interface of per_cu_dwarf_call for dwarf2_loc_desc_needs_frame. */ |
994 | ||
995 | static void | |
996 | needs_frame_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset) | |
997 | { | |
998 | struct needs_frame_baton *nf_baton = ctx->baton; | |
999 | ||
1000 | return per_cu_dwarf_call (ctx, die_offset, nf_baton->per_cu); | |
1001 | } | |
1002 | ||
4c2df51b DJ |
1003 | /* Return non-zero iff the location expression at DATA (length SIZE) |
1004 | requires a frame to evaluate. */ | |
1005 | ||
1006 | static int | |
947bb88f | 1007 | dwarf2_loc_desc_needs_frame (const gdb_byte *data, unsigned short size, |
ae0d2f24 | 1008 | struct dwarf2_per_cu_data *per_cu) |
4c2df51b DJ |
1009 | { |
1010 | struct needs_frame_baton baton; | |
1011 | struct dwarf_expr_context *ctx; | |
f630a401 | 1012 | int in_reg; |
4a227398 | 1013 | struct cleanup *old_chain; |
4c2df51b DJ |
1014 | |
1015 | baton.needs_frame = 0; | |
17ea53c3 | 1016 | baton.per_cu = per_cu; |
4c2df51b DJ |
1017 | |
1018 | ctx = new_dwarf_expr_context (); | |
4a227398 TT |
1019 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
1020 | ||
f7fd4728 | 1021 | ctx->gdbarch = get_objfile_arch (dwarf2_per_cu_objfile (per_cu)); |
ae0d2f24 | 1022 | ctx->addr_size = dwarf2_per_cu_addr_size (per_cu); |
4c2df51b DJ |
1023 | ctx->baton = &baton; |
1024 | ctx->read_reg = needs_frame_read_reg; | |
1025 | ctx->read_mem = needs_frame_read_mem; | |
1026 | ctx->get_frame_base = needs_frame_frame_base; | |
e7802207 | 1027 | ctx->get_frame_cfa = needs_frame_frame_cfa; |
4c2df51b | 1028 | ctx->get_tls_address = needs_frame_tls_address; |
5c631832 | 1029 | ctx->dwarf_call = needs_frame_dwarf_call; |
4c2df51b DJ |
1030 | |
1031 | dwarf_expr_eval (ctx, data, size); | |
1032 | ||
cec03d70 | 1033 | in_reg = ctx->location == DWARF_VALUE_REGISTER; |
f630a401 | 1034 | |
87808bd6 JB |
1035 | if (ctx->num_pieces > 0) |
1036 | { | |
1037 | int i; | |
1038 | ||
1039 | /* If the location has several pieces, and any of them are in | |
1040 | registers, then we will need a frame to fetch them from. */ | |
1041 | for (i = 0; i < ctx->num_pieces; i++) | |
cec03d70 | 1042 | if (ctx->pieces[i].location == DWARF_VALUE_REGISTER) |
87808bd6 JB |
1043 | in_reg = 1; |
1044 | } | |
1045 | ||
4a227398 | 1046 | do_cleanups (old_chain); |
4c2df51b | 1047 | |
f630a401 | 1048 | return baton.needs_frame || in_reg; |
4c2df51b DJ |
1049 | } |
1050 | ||
08922a10 SS |
1051 | /* This struct keeps track of the pieces that make up a multi-location |
1052 | object, for use in agent expression generation. It is | |
1053 | superficially similar to struct dwarf_expr_piece, but | |
1054 | dwarf_expr_piece is designed for use in immediate evaluation, and | |
1055 | does not, for example, have a way to record both base register and | |
1056 | offset. */ | |
1057 | ||
1058 | struct axs_var_loc | |
0d53c4c4 | 1059 | { |
08922a10 SS |
1060 | /* Memory vs register, etc */ |
1061 | enum axs_lvalue_kind kind; | |
1062 | ||
1063 | /* If non-zero, number of bytes in this fragment */ | |
1064 | unsigned bytes; | |
1065 | ||
1066 | /* (GDB-numbered) reg, or base reg if >= 0 */ | |
1067 | int reg; | |
1068 | ||
1069 | /* offset from reg */ | |
1070 | LONGEST offset; | |
1071 | }; | |
1072 | ||
0d45f56e | 1073 | static const gdb_byte * |
08922a10 SS |
1074 | dwarf2_tracepoint_var_loc (struct symbol *symbol, |
1075 | struct agent_expr *ax, | |
1076 | struct axs_var_loc *loc, | |
1077 | struct gdbarch *gdbarch, | |
0d45f56e | 1078 | const gdb_byte *data, const gdb_byte *end) |
08922a10 SS |
1079 | { |
1080 | if (data[0] >= DW_OP_reg0 && data[0] <= DW_OP_reg31) | |
0d53c4c4 | 1081 | { |
08922a10 SS |
1082 | loc->kind = axs_lvalue_register; |
1083 | loc->reg = gdbarch_dwarf2_reg_to_regnum (gdbarch, data[0] - DW_OP_reg0); | |
1084 | data += 1; | |
0d53c4c4 DJ |
1085 | } |
1086 | else if (data[0] == DW_OP_regx) | |
1087 | { | |
1088 | ULONGEST reg; | |
9a619af0 | 1089 | |
08922a10 SS |
1090 | data = read_uleb128 (data + 1, end, ®); |
1091 | loc->kind = axs_lvalue_register; | |
1092 | loc->reg = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); | |
0d53c4c4 DJ |
1093 | } |
1094 | else if (data[0] == DW_OP_fbreg) | |
1095 | { | |
0936ad1d SS |
1096 | struct block *b; |
1097 | struct symbol *framefunc; | |
1098 | int frame_reg = 0; | |
0d53c4c4 | 1099 | LONGEST frame_offset; |
0d45f56e | 1100 | const gdb_byte *base_data; |
0936ad1d SS |
1101 | size_t base_size; |
1102 | LONGEST base_offset = 0; | |
1103 | ||
1104 | b = block_for_pc (ax->scope); | |
1105 | ||
1106 | if (!b) | |
1107 | error (_("No block found for address")); | |
1108 | ||
1109 | framefunc = block_linkage_function (b); | |
1110 | ||
1111 | if (!framefunc) | |
1112 | error (_("No function found for block")); | |
1113 | ||
1114 | dwarf_expr_frame_base_1 (framefunc, ax->scope, | |
1115 | &base_data, &base_size); | |
1116 | ||
08922a10 | 1117 | if (base_data[0] >= DW_OP_breg0 && base_data[0] <= DW_OP_breg31) |
0936ad1d | 1118 | { |
0d45f56e TT |
1119 | const gdb_byte *buf_end; |
1120 | ||
0936ad1d | 1121 | frame_reg = base_data[0] - DW_OP_breg0; |
08922a10 SS |
1122 | buf_end = read_sleb128 (base_data + 1, |
1123 | base_data + base_size, &base_offset); | |
0936ad1d SS |
1124 | if (buf_end != base_data + base_size) |
1125 | error (_("Unexpected opcode after DW_OP_breg%u for symbol \"%s\"."), | |
1126 | frame_reg, SYMBOL_PRINT_NAME (symbol)); | |
1127 | } | |
08922a10 SS |
1128 | else if (base_data[0] >= DW_OP_reg0 && base_data[0] <= DW_OP_reg31) |
1129 | { | |
1130 | /* The frame base is just the register, with no offset. */ | |
1131 | frame_reg = base_data[0] - DW_OP_reg0; | |
1132 | base_offset = 0; | |
1133 | } | |
0936ad1d SS |
1134 | else |
1135 | { | |
1136 | /* We don't know what to do with the frame base expression, | |
1137 | so we can't trace this variable; give up. */ | |
08922a10 SS |
1138 | error (_("Cannot generate expression to collect symbol \"%s\"; DWARF 2 encoding not handled, first opcode in base data is 0x%x."), |
1139 | SYMBOL_PRINT_NAME (symbol), base_data[0]); | |
0936ad1d | 1140 | } |
0d53c4c4 | 1141 | |
08922a10 | 1142 | data = read_sleb128 (data + 1, end, &frame_offset); |
4c2df51b | 1143 | |
08922a10 SS |
1144 | loc->kind = axs_lvalue_memory; |
1145 | loc->reg = gdbarch_dwarf2_reg_to_regnum (gdbarch, frame_reg); | |
1146 | loc->offset = base_offset + frame_offset; | |
9c238357 | 1147 | } |
08922a10 | 1148 | else if (data[0] >= DW_OP_breg0 && data[0] <= DW_OP_breg31) |
9c238357 RC |
1149 | { |
1150 | unsigned int reg; | |
1151 | LONGEST offset; | |
9c238357 RC |
1152 | |
1153 | reg = data[0] - DW_OP_breg0; | |
08922a10 | 1154 | data = read_sleb128 (data + 1, end, &offset); |
9c238357 | 1155 | |
08922a10 SS |
1156 | loc->kind = axs_lvalue_memory; |
1157 | loc->reg = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); | |
1158 | loc->offset = offset; | |
0d53c4c4 DJ |
1159 | } |
1160 | else | |
9c238357 RC |
1161 | error (_("Unsupported DWARF opcode 0x%x in the location of \"%s\"."), |
1162 | data[0], SYMBOL_PRINT_NAME (symbol)); | |
08922a10 SS |
1163 | |
1164 | return data; | |
0d53c4c4 | 1165 | } |
08922a10 SS |
1166 | |
1167 | /* Given the location of a piece, issue bytecodes that will access it. */ | |
1168 | ||
1169 | static void | |
1170 | dwarf2_tracepoint_var_access (struct agent_expr *ax, | |
1171 | struct axs_value *value, | |
1172 | struct axs_var_loc *loc) | |
1173 | { | |
1174 | value->kind = loc->kind; | |
1175 | ||
1176 | switch (loc->kind) | |
1177 | { | |
1178 | case axs_lvalue_register: | |
1179 | value->u.reg = loc->reg; | |
1180 | break; | |
1181 | ||
1182 | case axs_lvalue_memory: | |
1183 | ax_reg (ax, loc->reg); | |
1184 | if (loc->offset) | |
1185 | { | |
1186 | ax_const_l (ax, loc->offset); | |
1187 | ax_simple (ax, aop_add); | |
1188 | } | |
1189 | break; | |
1190 | ||
1191 | default: | |
1192 | internal_error (__FILE__, __LINE__, _("Unhandled value kind in dwarf2_tracepoint_var_access")); | |
1193 | } | |
1194 | } | |
1195 | ||
1196 | static void | |
1197 | dwarf2_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch, | |
1198 | struct agent_expr *ax, struct axs_value *value, | |
0d45f56e | 1199 | const gdb_byte *data, int size) |
08922a10 | 1200 | { |
0d45f56e | 1201 | const gdb_byte *end = data + size; |
08922a10 SS |
1202 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
1203 | /* In practice, a variable is not going to be spread across | |
1204 | dozens of registers or memory locations. If someone comes up | |
1205 | with a real-world example, revisit this. */ | |
1206 | #define MAX_FRAGS 16 | |
1207 | struct axs_var_loc fragments[MAX_FRAGS]; | |
1208 | int nfrags = 0, frag; | |
1209 | int length = 0; | |
1210 | int piece_ok = 0; | |
1211 | int bad = 0; | |
1212 | int first = 1; | |
1213 | ||
1214 | if (!data || size == 0) | |
1215 | { | |
1216 | value->optimized_out = 1; | |
1217 | return; | |
1218 | } | |
1219 | ||
1220 | while (data < end) | |
1221 | { | |
1222 | if (!piece_ok) | |
1223 | { | |
1224 | if (nfrags == MAX_FRAGS) | |
1225 | error (_("Too many pieces in location for \"%s\"."), | |
1226 | SYMBOL_PRINT_NAME (symbol)); | |
1227 | ||
1228 | fragments[nfrags].bytes = 0; | |
1229 | data = dwarf2_tracepoint_var_loc (symbol, ax, &fragments[nfrags], | |
1230 | gdbarch, data, end); | |
1231 | nfrags++; | |
1232 | piece_ok = 1; | |
1233 | } | |
1234 | else if (data[0] == DW_OP_piece) | |
1235 | { | |
1236 | ULONGEST bytes; | |
1237 | ||
1238 | data = read_uleb128 (data + 1, end, &bytes); | |
1239 | /* Only deal with 4 byte fragments for now. */ | |
1240 | if (bytes != 4) | |
1241 | error (_("DW_OP_piece %s not supported in location for \"%s\"."), | |
1242 | pulongest (bytes), SYMBOL_PRINT_NAME (symbol)); | |
1243 | fragments[nfrags - 1].bytes = bytes; | |
1244 | length += bytes; | |
1245 | piece_ok = 0; | |
1246 | } | |
1247 | else | |
1248 | { | |
1249 | bad = 1; | |
1250 | break; | |
1251 | } | |
1252 | } | |
1253 | ||
1254 | if (bad || data > end) | |
1255 | error (_("Corrupted DWARF expression for \"%s\"."), | |
1256 | SYMBOL_PRINT_NAME (symbol)); | |
1257 | ||
1258 | /* If single expression, no pieces, convert to external format. */ | |
1259 | if (length == 0) | |
1260 | { | |
1261 | dwarf2_tracepoint_var_access (ax, value, &fragments[0]); | |
1262 | return; | |
1263 | } | |
1264 | ||
1265 | if (length != TYPE_LENGTH (value->type)) | |
1266 | error (_("Inconsistent piece information for \"%s\"."), | |
1267 | SYMBOL_PRINT_NAME (symbol)); | |
1268 | ||
1269 | /* Emit bytecodes to assemble the pieces into a single stack entry. */ | |
1270 | ||
1271 | for ((frag = (byte_order == BFD_ENDIAN_BIG ? 0 : nfrags - 1)); | |
1272 | nfrags--; | |
1273 | (frag += (byte_order == BFD_ENDIAN_BIG ? 1 : -1))) | |
1274 | { | |
1275 | if (!first) | |
1276 | { | |
1277 | /* shift the previous fragment up 32 bits */ | |
1278 | ax_const_l (ax, 32); | |
1279 | ax_simple (ax, aop_lsh); | |
1280 | } | |
1281 | ||
1282 | dwarf2_tracepoint_var_access (ax, value, &fragments[frag]); | |
1283 | ||
1284 | switch (value->kind) | |
1285 | { | |
1286 | case axs_lvalue_register: | |
1287 | ax_reg (ax, value->u.reg); | |
1288 | break; | |
1289 | ||
1290 | case axs_lvalue_memory: | |
1291 | { | |
1292 | extern int trace_kludge; /* Ugh. */ | |
1293 | ||
1294 | gdb_assert (fragments[frag].bytes == 4); | |
1295 | if (trace_kludge) | |
1296 | ax_trace_quick (ax, 4); | |
1297 | ax_simple (ax, aop_ref32); | |
1298 | } | |
1299 | break; | |
1300 | } | |
1301 | ||
1302 | if (!first) | |
1303 | { | |
1304 | /* or the new fragment into the previous */ | |
1305 | ax_zero_ext (ax, 32); | |
1306 | ax_simple (ax, aop_bit_or); | |
1307 | } | |
1308 | first = 0; | |
1309 | } | |
1310 | value->kind = axs_rvalue; | |
1311 | } | |
1312 | ||
4c2df51b DJ |
1313 | \f |
1314 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression | |
1315 | evaluator to calculate the location. */ | |
1316 | static struct value * | |
1317 | locexpr_read_variable (struct symbol *symbol, struct frame_info *frame) | |
1318 | { | |
1319 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
1320 | struct value *val; | |
9a619af0 | 1321 | |
a2d33775 JK |
1322 | val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, dlbaton->data, |
1323 | dlbaton->size, dlbaton->per_cu); | |
4c2df51b DJ |
1324 | |
1325 | return val; | |
1326 | } | |
1327 | ||
1328 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ | |
1329 | static int | |
1330 | locexpr_read_needs_frame (struct symbol *symbol) | |
1331 | { | |
1332 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
9a619af0 | 1333 | |
ae0d2f24 UW |
1334 | return dwarf2_loc_desc_needs_frame (dlbaton->data, dlbaton->size, |
1335 | dlbaton->per_cu); | |
4c2df51b DJ |
1336 | } |
1337 | ||
9eae7c52 TT |
1338 | /* Return true if DATA points to the end of a piece. END is one past |
1339 | the last byte in the expression. */ | |
1340 | ||
1341 | static int | |
1342 | piece_end_p (const gdb_byte *data, const gdb_byte *end) | |
1343 | { | |
1344 | return data == end || data[0] == DW_OP_piece || data[0] == DW_OP_bit_piece; | |
1345 | } | |
1346 | ||
1347 | /* Nicely describe a single piece of a location, returning an updated | |
1348 | position in the bytecode sequence. This function cannot recognize | |
1349 | all locations; if a location is not recognized, it simply returns | |
1350 | DATA. */ | |
08922a10 | 1351 | |
0d45f56e | 1352 | static const gdb_byte * |
08922a10 SS |
1353 | locexpr_describe_location_piece (struct symbol *symbol, struct ui_file *stream, |
1354 | CORE_ADDR addr, struct objfile *objfile, | |
9eae7c52 | 1355 | const gdb_byte *data, const gdb_byte *end, |
0d45f56e | 1356 | unsigned int addr_size) |
4c2df51b | 1357 | { |
08922a10 SS |
1358 | struct gdbarch *gdbarch = get_objfile_arch (objfile); |
1359 | int regno; | |
1360 | ||
1361 | if (data[0] >= DW_OP_reg0 && data[0] <= DW_OP_reg31) | |
1362 | { | |
1363 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, data[0] - DW_OP_reg0); | |
1364 | fprintf_filtered (stream, _("a variable in $%s"), | |
1365 | gdbarch_register_name (gdbarch, regno)); | |
1366 | data += 1; | |
1367 | } | |
1368 | else if (data[0] == DW_OP_regx) | |
1369 | { | |
1370 | ULONGEST reg; | |
4c2df51b | 1371 | |
9eae7c52 | 1372 | data = read_uleb128 (data + 1, end, ®); |
08922a10 SS |
1373 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); |
1374 | fprintf_filtered (stream, _("a variable in $%s"), | |
1375 | gdbarch_register_name (gdbarch, regno)); | |
1376 | } | |
1377 | else if (data[0] == DW_OP_fbreg) | |
4c2df51b | 1378 | { |
08922a10 SS |
1379 | struct block *b; |
1380 | struct symbol *framefunc; | |
1381 | int frame_reg = 0; | |
1382 | LONGEST frame_offset; | |
9eae7c52 | 1383 | const gdb_byte *base_data, *new_data; |
08922a10 SS |
1384 | size_t base_size; |
1385 | LONGEST base_offset = 0; | |
1386 | ||
9eae7c52 TT |
1387 | new_data = read_sleb128 (data + 1, end, &frame_offset); |
1388 | if (!piece_end_p (new_data, end)) | |
1389 | return data; | |
1390 | data = new_data; | |
1391 | ||
08922a10 SS |
1392 | b = block_for_pc (addr); |
1393 | ||
1394 | if (!b) | |
1395 | error (_("No block found for address for symbol \"%s\"."), | |
1396 | SYMBOL_PRINT_NAME (symbol)); | |
1397 | ||
1398 | framefunc = block_linkage_function (b); | |
1399 | ||
1400 | if (!framefunc) | |
1401 | error (_("No function found for block for symbol \"%s\"."), | |
1402 | SYMBOL_PRINT_NAME (symbol)); | |
1403 | ||
1404 | dwarf_expr_frame_base_1 (framefunc, addr, &base_data, &base_size); | |
1405 | ||
1406 | if (base_data[0] >= DW_OP_breg0 && base_data[0] <= DW_OP_breg31) | |
1407 | { | |
0d45f56e | 1408 | const gdb_byte *buf_end; |
08922a10 SS |
1409 | |
1410 | frame_reg = base_data[0] - DW_OP_breg0; | |
1411 | buf_end = read_sleb128 (base_data + 1, | |
1412 | base_data + base_size, &base_offset); | |
1413 | if (buf_end != base_data + base_size) | |
1414 | error (_("Unexpected opcode after DW_OP_breg%u for symbol \"%s\"."), | |
1415 | frame_reg, SYMBOL_PRINT_NAME (symbol)); | |
1416 | } | |
1417 | else if (base_data[0] >= DW_OP_reg0 && base_data[0] <= DW_OP_reg31) | |
1418 | { | |
1419 | /* The frame base is just the register, with no offset. */ | |
1420 | frame_reg = base_data[0] - DW_OP_reg0; | |
1421 | base_offset = 0; | |
1422 | } | |
1423 | else | |
1424 | { | |
1425 | /* We don't know what to do with the frame base expression, | |
1426 | so we can't trace this variable; give up. */ | |
1427 | error (_("Cannot describe location of symbol \"%s\"; " | |
1428 | "DWARF 2 encoding not handled, " | |
1429 | "first opcode in base data is 0x%x."), | |
1430 | SYMBOL_PRINT_NAME (symbol), base_data[0]); | |
1431 | } | |
1432 | ||
1433 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, frame_reg); | |
1434 | ||
08922a10 SS |
1435 | fprintf_filtered (stream, _("a variable at frame base reg $%s offset %s+%s"), |
1436 | gdbarch_register_name (gdbarch, regno), | |
1437 | plongest (base_offset), plongest (frame_offset)); | |
1438 | } | |
9eae7c52 TT |
1439 | else if (data[0] >= DW_OP_breg0 && data[0] <= DW_OP_breg31 |
1440 | && piece_end_p (data, end)) | |
08922a10 SS |
1441 | { |
1442 | LONGEST offset; | |
1443 | ||
1444 | regno = gdbarch_dwarf2_reg_to_regnum (gdbarch, data[0] - DW_OP_breg0); | |
1445 | ||
9eae7c52 | 1446 | data = read_sleb128 (data + 1, end, &offset); |
08922a10 | 1447 | |
4c2df51b | 1448 | fprintf_filtered (stream, |
08922a10 SS |
1449 | _("a variable at offset %s from base reg $%s"), |
1450 | plongest (offset), | |
5e2b427d | 1451 | gdbarch_register_name (gdbarch, regno)); |
4c2df51b DJ |
1452 | } |
1453 | ||
c3228f12 EZ |
1454 | /* The location expression for a TLS variable looks like this (on a |
1455 | 64-bit LE machine): | |
1456 | ||
1457 | DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0 | |
1458 | (DW_OP_addr: 4; DW_OP_GNU_push_tls_address) | |
1459 | ||
1460 | 0x3 is the encoding for DW_OP_addr, which has an operand as long | |
1461 | as the size of an address on the target machine (here is 8 | |
1462 | bytes). 0xe0 is the encoding for DW_OP_GNU_push_tls_address. | |
1463 | The operand represents the offset at which the variable is within | |
1464 | the thread local storage. */ | |
1465 | ||
9eae7c52 TT |
1466 | else if (data + 1 + addr_size < end |
1467 | && data[0] == DW_OP_addr | |
1468 | && data[1 + addr_size] == DW_OP_GNU_push_tls_address | |
1469 | && piece_end_p (data + 2 + addr_size, end)) | |
08922a10 SS |
1470 | { |
1471 | CORE_ADDR offset = dwarf2_read_address (gdbarch, | |
1472 | data + 1, | |
9eae7c52 | 1473 | end, |
08922a10 | 1474 | addr_size); |
9a619af0 | 1475 | |
08922a10 SS |
1476 | fprintf_filtered (stream, |
1477 | _("a thread-local variable at offset %s " | |
1478 | "in the thread-local storage for `%s'"), | |
1479 | paddress (gdbarch, offset), objfile->name); | |
1480 | ||
1481 | data += 1 + addr_size + 1; | |
1482 | } | |
9eae7c52 TT |
1483 | else if (data[0] >= DW_OP_lit0 |
1484 | && data[0] <= DW_OP_lit31 | |
1485 | && data + 1 < end | |
1486 | && data[1] == DW_OP_stack_value) | |
1487 | { | |
1488 | fprintf_filtered (stream, _("the constant %d"), data[0] - DW_OP_lit0); | |
1489 | data += 2; | |
1490 | } | |
1491 | ||
1492 | return data; | |
1493 | } | |
1494 | ||
1495 | /* Disassemble an expression, stopping at the end of a piece or at the | |
1496 | end of the expression. Returns a pointer to the next unread byte | |
1497 | in the input expression. If ALL is nonzero, then this function | |
1498 | will keep going until it reaches the end of the expression. */ | |
1499 | ||
1500 | static const gdb_byte * | |
1501 | disassemble_dwarf_expression (struct ui_file *stream, | |
1502 | struct gdbarch *arch, unsigned int addr_size, | |
1503 | int offset_size, | |
1504 | const gdb_byte *data, const gdb_byte *end, | |
1505 | int all) | |
1506 | { | |
1507 | const gdb_byte *start = data; | |
1508 | ||
1509 | fprintf_filtered (stream, _("a complex DWARF expression:\n")); | |
1510 | ||
1511 | while (data < end | |
1512 | && (all | |
1513 | || (data[0] != DW_OP_piece && data[0] != DW_OP_bit_piece))) | |
1514 | { | |
1515 | enum dwarf_location_atom op = *data++; | |
1516 | CORE_ADDR addr; | |
1517 | ULONGEST ul; | |
1518 | LONGEST l; | |
1519 | const char *name; | |
1520 | ||
1521 | name = dwarf_stack_op_name (op, 0); | |
1522 | ||
1523 | if (!name) | |
1524 | error (_("Unrecognized DWARF opcode 0x%02x at %ld"), | |
1525 | op, (long) (data - start)); | |
1526 | fprintf_filtered (stream, " % 4ld: %s", (long) (data - start), name); | |
1527 | ||
1528 | switch (op) | |
1529 | { | |
1530 | case DW_OP_addr: | |
1531 | addr = dwarf2_read_address (arch, data, end, addr_size); | |
1532 | data += addr_size; | |
1533 | fprintf_filtered (stream, " %s", paddress (arch, addr)); | |
1534 | break; | |
1535 | ||
1536 | case DW_OP_const1u: | |
1537 | ul = extract_unsigned_integer (data, 1, gdbarch_byte_order (arch)); | |
1538 | data += 1; | |
1539 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1540 | break; | |
1541 | case DW_OP_const1s: | |
1542 | l = extract_signed_integer (data, 1, gdbarch_byte_order (arch)); | |
1543 | data += 1; | |
1544 | fprintf_filtered (stream, " %s", plongest (l)); | |
1545 | break; | |
1546 | case DW_OP_const2u: | |
1547 | ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch)); | |
1548 | data += 2; | |
1549 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1550 | break; | |
1551 | case DW_OP_const2s: | |
1552 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); | |
1553 | data += 2; | |
1554 | fprintf_filtered (stream, " %s", plongest (l)); | |
1555 | break; | |
1556 | case DW_OP_const4u: | |
1557 | ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch)); | |
1558 | data += 4; | |
1559 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1560 | break; | |
1561 | case DW_OP_const4s: | |
1562 | l = extract_signed_integer (data, 4, gdbarch_byte_order (arch)); | |
1563 | data += 4; | |
1564 | fprintf_filtered (stream, " %s", plongest (l)); | |
1565 | break; | |
1566 | case DW_OP_const8u: | |
1567 | ul = extract_unsigned_integer (data, 8, gdbarch_byte_order (arch)); | |
1568 | data += 8; | |
1569 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1570 | break; | |
1571 | case DW_OP_const8s: | |
1572 | l = extract_signed_integer (data, 8, gdbarch_byte_order (arch)); | |
1573 | data += 8; | |
1574 | fprintf_filtered (stream, " %s", plongest (l)); | |
1575 | break; | |
1576 | case DW_OP_constu: | |
1577 | data = read_uleb128 (data, end, &ul); | |
1578 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1579 | break; | |
1580 | case DW_OP_consts: | |
44b5680a | 1581 | data = read_sleb128 (data, end, &l); |
9eae7c52 TT |
1582 | fprintf_filtered (stream, " %s", plongest (l)); |
1583 | break; | |
1584 | ||
1585 | case DW_OP_reg0: | |
1586 | case DW_OP_reg1: | |
1587 | case DW_OP_reg2: | |
1588 | case DW_OP_reg3: | |
1589 | case DW_OP_reg4: | |
1590 | case DW_OP_reg5: | |
1591 | case DW_OP_reg6: | |
1592 | case DW_OP_reg7: | |
1593 | case DW_OP_reg8: | |
1594 | case DW_OP_reg9: | |
1595 | case DW_OP_reg10: | |
1596 | case DW_OP_reg11: | |
1597 | case DW_OP_reg12: | |
1598 | case DW_OP_reg13: | |
1599 | case DW_OP_reg14: | |
1600 | case DW_OP_reg15: | |
1601 | case DW_OP_reg16: | |
1602 | case DW_OP_reg17: | |
1603 | case DW_OP_reg18: | |
1604 | case DW_OP_reg19: | |
1605 | case DW_OP_reg20: | |
1606 | case DW_OP_reg21: | |
1607 | case DW_OP_reg22: | |
1608 | case DW_OP_reg23: | |
1609 | case DW_OP_reg24: | |
1610 | case DW_OP_reg25: | |
1611 | case DW_OP_reg26: | |
1612 | case DW_OP_reg27: | |
1613 | case DW_OP_reg28: | |
1614 | case DW_OP_reg29: | |
1615 | case DW_OP_reg30: | |
1616 | case DW_OP_reg31: | |
1617 | fprintf_filtered (stream, " [$%s]", | |
1618 | gdbarch_register_name (arch, op - DW_OP_reg0)); | |
1619 | break; | |
1620 | ||
1621 | case DW_OP_regx: | |
1622 | data = read_uleb128 (data, end, &ul); | |
1623 | fprintf_filtered (stream, " %s [$%s]", pulongest (ul), | |
1624 | gdbarch_register_name (arch, (int) ul)); | |
1625 | break; | |
1626 | ||
1627 | case DW_OP_implicit_value: | |
1628 | data = read_uleb128 (data, end, &ul); | |
1629 | data += ul; | |
1630 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1631 | break; | |
1632 | ||
1633 | case DW_OP_breg0: | |
1634 | case DW_OP_breg1: | |
1635 | case DW_OP_breg2: | |
1636 | case DW_OP_breg3: | |
1637 | case DW_OP_breg4: | |
1638 | case DW_OP_breg5: | |
1639 | case DW_OP_breg6: | |
1640 | case DW_OP_breg7: | |
1641 | case DW_OP_breg8: | |
1642 | case DW_OP_breg9: | |
1643 | case DW_OP_breg10: | |
1644 | case DW_OP_breg11: | |
1645 | case DW_OP_breg12: | |
1646 | case DW_OP_breg13: | |
1647 | case DW_OP_breg14: | |
1648 | case DW_OP_breg15: | |
1649 | case DW_OP_breg16: | |
1650 | case DW_OP_breg17: | |
1651 | case DW_OP_breg18: | |
1652 | case DW_OP_breg19: | |
1653 | case DW_OP_breg20: | |
1654 | case DW_OP_breg21: | |
1655 | case DW_OP_breg22: | |
1656 | case DW_OP_breg23: | |
1657 | case DW_OP_breg24: | |
1658 | case DW_OP_breg25: | |
1659 | case DW_OP_breg26: | |
1660 | case DW_OP_breg27: | |
1661 | case DW_OP_breg28: | |
1662 | case DW_OP_breg29: | |
1663 | case DW_OP_breg30: | |
1664 | case DW_OP_breg31: | |
1665 | data = read_sleb128 (data, end, &ul); | |
1666 | fprintf_filtered (stream, " %s [$%s]", pulongest (ul), | |
1667 | gdbarch_register_name (arch, op - DW_OP_breg0)); | |
1668 | break; | |
1669 | ||
1670 | case DW_OP_bregx: | |
1671 | { | |
1672 | ULONGEST offset; | |
1673 | ||
1674 | data = read_uleb128 (data, end, &ul); | |
1675 | data = read_sleb128 (data, end, &offset); | |
1676 | fprintf_filtered (stream, " register %s [$%s] offset %s", | |
1677 | pulongest (ul), | |
1678 | gdbarch_register_name (arch, (int) ul), | |
1679 | pulongest (offset)); | |
1680 | } | |
1681 | break; | |
1682 | ||
1683 | case DW_OP_fbreg: | |
1684 | data = read_sleb128 (data, end, &ul); | |
1685 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1686 | break; | |
1687 | ||
1688 | case DW_OP_xderef_size: | |
1689 | case DW_OP_deref_size: | |
1690 | case DW_OP_pick: | |
1691 | fprintf_filtered (stream, " %d", *data); | |
1692 | ++data; | |
1693 | break; | |
1694 | ||
1695 | case DW_OP_plus_uconst: | |
1696 | data = read_uleb128 (data, end, &ul); | |
1697 | fprintf_filtered (stream, " %s", pulongest (ul)); | |
1698 | break; | |
1699 | ||
1700 | case DW_OP_skip: | |
1701 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); | |
1702 | data += 2; | |
1703 | fprintf_filtered (stream, " to %ld", | |
1704 | (long) (data + l - start)); | |
1705 | break; | |
1706 | ||
1707 | case DW_OP_bra: | |
1708 | l = extract_signed_integer (data, 2, gdbarch_byte_order (arch)); | |
1709 | data += 2; | |
1710 | fprintf_filtered (stream, " %ld", | |
1711 | (long) (data + l - start)); | |
1712 | break; | |
1713 | ||
1714 | case DW_OP_call2: | |
1715 | ul = extract_unsigned_integer (data, 2, gdbarch_byte_order (arch)); | |
1716 | data += 2; | |
1717 | fprintf_filtered (stream, " offset %s", phex_nz (ul, 2)); | |
1718 | break; | |
1719 | ||
1720 | case DW_OP_call4: | |
1721 | ul = extract_unsigned_integer (data, 4, gdbarch_byte_order (arch)); | |
1722 | data += 4; | |
1723 | fprintf_filtered (stream, " offset %s", phex_nz (ul, 4)); | |
1724 | break; | |
1725 | ||
1726 | case DW_OP_call_ref: | |
1727 | ul = extract_unsigned_integer (data, offset_size, | |
1728 | gdbarch_byte_order (arch)); | |
1729 | data += offset_size; | |
1730 | fprintf_filtered (stream, " offset %s", phex_nz (ul, offset_size)); | |
1731 | break; | |
1732 | ||
1733 | case DW_OP_piece: | |
1734 | data = read_uleb128 (data, end, &ul); | |
1735 | fprintf_filtered (stream, " %s (bytes)", pulongest (ul)); | |
1736 | break; | |
1737 | ||
1738 | case DW_OP_bit_piece: | |
1739 | { | |
1740 | ULONGEST offset; | |
1741 | ||
1742 | data = read_uleb128 (data, end, &ul); | |
1743 | data = read_uleb128 (data, end, &offset); | |
1744 | fprintf_filtered (stream, " size %s offset %s (bits)", | |
1745 | pulongest (ul), pulongest (offset)); | |
1746 | } | |
1747 | break; | |
1748 | } | |
1749 | ||
1750 | fprintf_filtered (stream, "\n"); | |
1751 | } | |
c3228f12 | 1752 | |
08922a10 | 1753 | return data; |
4c2df51b DJ |
1754 | } |
1755 | ||
08922a10 SS |
1756 | /* Describe a single location, which may in turn consist of multiple |
1757 | pieces. */ | |
a55cc764 | 1758 | |
08922a10 SS |
1759 | static void |
1760 | locexpr_describe_location_1 (struct symbol *symbol, CORE_ADDR addr, | |
0d45f56e TT |
1761 | struct ui_file *stream, |
1762 | const gdb_byte *data, int size, | |
9eae7c52 TT |
1763 | struct objfile *objfile, unsigned int addr_size, |
1764 | int offset_size) | |
08922a10 | 1765 | { |
0d45f56e | 1766 | const gdb_byte *end = data + size; |
9eae7c52 | 1767 | int first_piece = 1, bad = 0; |
08922a10 | 1768 | |
08922a10 SS |
1769 | while (data < end) |
1770 | { | |
9eae7c52 TT |
1771 | const gdb_byte *here = data; |
1772 | int disassemble = 1; | |
1773 | ||
1774 | if (first_piece) | |
1775 | first_piece = 0; | |
1776 | else | |
1777 | fprintf_filtered (stream, _(", and ")); | |
08922a10 | 1778 | |
9eae7c52 TT |
1779 | if (!dwarf2_always_disassemble) |
1780 | { | |
08922a10 | 1781 | data = locexpr_describe_location_piece (symbol, stream, addr, objfile, |
9eae7c52 TT |
1782 | data, end, addr_size); |
1783 | /* If we printed anything, or if we have an empty piece, | |
1784 | then don't disassemble. */ | |
1785 | if (data != here | |
1786 | || data[0] == DW_OP_piece | |
1787 | || data[0] == DW_OP_bit_piece) | |
1788 | disassemble = 0; | |
08922a10 | 1789 | } |
9eae7c52 TT |
1790 | if (disassemble) |
1791 | data = disassemble_dwarf_expression (stream, get_objfile_arch (objfile), | |
1792 | addr_size, offset_size, data, end, | |
1793 | dwarf2_always_disassemble); | |
1794 | ||
1795 | if (data < end) | |
08922a10 | 1796 | { |
9eae7c52 | 1797 | int empty = data == here; |
08922a10 | 1798 | |
9eae7c52 TT |
1799 | if (disassemble) |
1800 | fprintf_filtered (stream, " "); | |
1801 | if (data[0] == DW_OP_piece) | |
1802 | { | |
1803 | ULONGEST bytes; | |
08922a10 | 1804 | |
9eae7c52 | 1805 | data = read_uleb128 (data + 1, end, &bytes); |
08922a10 | 1806 | |
9eae7c52 TT |
1807 | if (empty) |
1808 | fprintf_filtered (stream, _("an empty %s-byte piece"), | |
1809 | pulongest (bytes)); | |
1810 | else | |
1811 | fprintf_filtered (stream, _(" [%s-byte piece]"), | |
1812 | pulongest (bytes)); | |
1813 | } | |
1814 | else if (data[0] == DW_OP_bit_piece) | |
1815 | { | |
1816 | ULONGEST bits, offset; | |
1817 | ||
1818 | data = read_uleb128 (data + 1, end, &bits); | |
1819 | data = read_uleb128 (data, end, &offset); | |
1820 | ||
1821 | if (empty) | |
1822 | fprintf_filtered (stream, | |
1823 | _("an empty %s-bit piece"), | |
1824 | pulongest (bits)); | |
1825 | else | |
1826 | fprintf_filtered (stream, | |
1827 | _(" [%s-bit piece, offset %s bits]"), | |
1828 | pulongest (bits), pulongest (offset)); | |
1829 | } | |
1830 | else | |
1831 | { | |
1832 | bad = 1; | |
1833 | break; | |
1834 | } | |
08922a10 SS |
1835 | } |
1836 | } | |
1837 | ||
1838 | if (bad || data > end) | |
1839 | error (_("Corrupted DWARF2 expression for \"%s\"."), | |
1840 | SYMBOL_PRINT_NAME (symbol)); | |
1841 | } | |
1842 | ||
1843 | /* Print a natural-language description of SYMBOL to STREAM. This | |
1844 | version is for a symbol with a single location. */ | |
a55cc764 | 1845 | |
08922a10 SS |
1846 | static void |
1847 | locexpr_describe_location (struct symbol *symbol, CORE_ADDR addr, | |
1848 | struct ui_file *stream) | |
1849 | { | |
1850 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
1851 | struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu); | |
1852 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); | |
9eae7c52 | 1853 | int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu); |
08922a10 SS |
1854 | |
1855 | locexpr_describe_location_1 (symbol, addr, stream, dlbaton->data, dlbaton->size, | |
9eae7c52 | 1856 | objfile, addr_size, offset_size); |
08922a10 SS |
1857 | } |
1858 | ||
1859 | /* Describe the location of SYMBOL as an agent value in VALUE, generating | |
1860 | any necessary bytecode in AX. */ | |
a55cc764 | 1861 | |
0d53c4c4 | 1862 | static void |
505e835d UW |
1863 | locexpr_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch, |
1864 | struct agent_expr *ax, struct axs_value *value) | |
a55cc764 DJ |
1865 | { |
1866 | struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
1867 | ||
505e835d UW |
1868 | dwarf2_tracepoint_var_ref (symbol, gdbarch, ax, value, |
1869 | dlbaton->data, dlbaton->size); | |
a55cc764 DJ |
1870 | } |
1871 | ||
4c2df51b DJ |
1872 | /* The set of location functions used with the DWARF-2 expression |
1873 | evaluator. */ | |
768a979c | 1874 | const struct symbol_computed_ops dwarf2_locexpr_funcs = { |
4c2df51b DJ |
1875 | locexpr_read_variable, |
1876 | locexpr_read_needs_frame, | |
1877 | locexpr_describe_location, | |
a55cc764 | 1878 | locexpr_tracepoint_var_ref |
4c2df51b | 1879 | }; |
0d53c4c4 DJ |
1880 | |
1881 | ||
1882 | /* Wrapper functions for location lists. These generally find | |
1883 | the appropriate location expression and call something above. */ | |
1884 | ||
1885 | /* Return the value of SYMBOL in FRAME using the DWARF-2 expression | |
1886 | evaluator to calculate the location. */ | |
1887 | static struct value * | |
1888 | loclist_read_variable (struct symbol *symbol, struct frame_info *frame) | |
1889 | { | |
1890 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
1891 | struct value *val; | |
947bb88f | 1892 | const gdb_byte *data; |
b6b08ebf | 1893 | size_t size; |
0d53c4c4 DJ |
1894 | |
1895 | data = find_location_expression (dlbaton, &size, | |
22c6caba JW |
1896 | frame ? get_frame_address_in_block (frame) |
1897 | : 0); | |
0d53c4c4 | 1898 | if (data == NULL) |
806048c6 DJ |
1899 | { |
1900 | val = allocate_value (SYMBOL_TYPE (symbol)); | |
1901 | VALUE_LVAL (val) = not_lval; | |
1902 | set_value_optimized_out (val, 1); | |
1903 | } | |
1904 | else | |
a2d33775 | 1905 | val = dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol), frame, data, size, |
ae0d2f24 | 1906 | dlbaton->per_cu); |
0d53c4c4 DJ |
1907 | |
1908 | return val; | |
1909 | } | |
1910 | ||
1911 | /* Return non-zero iff we need a frame to evaluate SYMBOL. */ | |
1912 | static int | |
1913 | loclist_read_needs_frame (struct symbol *symbol) | |
1914 | { | |
1915 | /* If there's a location list, then assume we need to have a frame | |
1916 | to choose the appropriate location expression. With tracking of | |
1917 | global variables this is not necessarily true, but such tracking | |
1918 | is disabled in GCC at the moment until we figure out how to | |
1919 | represent it. */ | |
1920 | ||
1921 | return 1; | |
1922 | } | |
1923 | ||
08922a10 SS |
1924 | /* Print a natural-language description of SYMBOL to STREAM. This |
1925 | version applies when there is a list of different locations, each | |
1926 | with a specified address range. */ | |
1927 | ||
1928 | static void | |
1929 | loclist_describe_location (struct symbol *symbol, CORE_ADDR addr, | |
1930 | struct ui_file *stream) | |
0d53c4c4 | 1931 | { |
08922a10 SS |
1932 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); |
1933 | CORE_ADDR low, high; | |
947bb88f | 1934 | const gdb_byte *loc_ptr, *buf_end; |
08922a10 SS |
1935 | int length, first = 1; |
1936 | struct objfile *objfile = dwarf2_per_cu_objfile (dlbaton->per_cu); | |
1937 | struct gdbarch *gdbarch = get_objfile_arch (objfile); | |
1938 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); | |
1939 | unsigned int addr_size = dwarf2_per_cu_addr_size (dlbaton->per_cu); | |
9eae7c52 | 1940 | int offset_size = dwarf2_per_cu_offset_size (dlbaton->per_cu); |
08922a10 SS |
1941 | CORE_ADDR base_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1)); |
1942 | /* Adjust base_address for relocatable objects. */ | |
1943 | CORE_ADDR base_offset = ANOFFSET (objfile->section_offsets, | |
1944 | SECT_OFF_TEXT (objfile)); | |
1945 | CORE_ADDR base_address = dlbaton->base_address + base_offset; | |
1946 | ||
1947 | loc_ptr = dlbaton->data; | |
1948 | buf_end = dlbaton->data + dlbaton->size; | |
1949 | ||
9eae7c52 | 1950 | fprintf_filtered (stream, _("multi-location:\n")); |
08922a10 SS |
1951 | |
1952 | /* Iterate through locations until we run out. */ | |
1953 | while (1) | |
1954 | { | |
1955 | if (buf_end - loc_ptr < 2 * addr_size) | |
1956 | error (_("Corrupted DWARF expression for symbol \"%s\"."), | |
1957 | SYMBOL_PRINT_NAME (symbol)); | |
1958 | ||
1959 | low = extract_unsigned_integer (loc_ptr, addr_size, byte_order); | |
1960 | loc_ptr += addr_size; | |
1961 | ||
1962 | /* A base-address-selection entry. */ | |
1963 | if (low == base_mask) | |
1964 | { | |
1965 | base_address = dwarf2_read_address (gdbarch, | |
1966 | loc_ptr, buf_end, addr_size); | |
9eae7c52 | 1967 | fprintf_filtered (stream, _(" Base address %s"), |
08922a10 SS |
1968 | paddress (gdbarch, base_address)); |
1969 | loc_ptr += addr_size; | |
1970 | continue; | |
1971 | } | |
1972 | ||
1973 | high = extract_unsigned_integer (loc_ptr, addr_size, byte_order); | |
1974 | loc_ptr += addr_size; | |
1975 | ||
1976 | /* An end-of-list entry. */ | |
1977 | if (low == 0 && high == 0) | |
9eae7c52 | 1978 | break; |
08922a10 SS |
1979 | |
1980 | /* Otherwise, a location expression entry. */ | |
1981 | low += base_address; | |
1982 | high += base_address; | |
1983 | ||
1984 | length = extract_unsigned_integer (loc_ptr, 2, byte_order); | |
1985 | loc_ptr += 2; | |
1986 | ||
08922a10 SS |
1987 | /* (It would improve readability to print only the minimum |
1988 | necessary digits of the second number of the range.) */ | |
9eae7c52 | 1989 | fprintf_filtered (stream, _(" Range %s-%s: "), |
08922a10 SS |
1990 | paddress (gdbarch, low), paddress (gdbarch, high)); |
1991 | ||
1992 | /* Now describe this particular location. */ | |
1993 | locexpr_describe_location_1 (symbol, low, stream, loc_ptr, length, | |
9eae7c52 TT |
1994 | objfile, addr_size, offset_size); |
1995 | ||
1996 | fprintf_filtered (stream, "\n"); | |
08922a10 SS |
1997 | |
1998 | loc_ptr += length; | |
1999 | } | |
0d53c4c4 DJ |
2000 | } |
2001 | ||
2002 | /* Describe the location of SYMBOL as an agent value in VALUE, generating | |
2003 | any necessary bytecode in AX. */ | |
2004 | static void | |
505e835d UW |
2005 | loclist_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch, |
2006 | struct agent_expr *ax, struct axs_value *value) | |
0d53c4c4 DJ |
2007 | { |
2008 | struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol); | |
947bb88f | 2009 | const gdb_byte *data; |
b6b08ebf | 2010 | size_t size; |
0d53c4c4 DJ |
2011 | |
2012 | data = find_location_expression (dlbaton, &size, ax->scope); | |
0d53c4c4 | 2013 | |
505e835d | 2014 | dwarf2_tracepoint_var_ref (symbol, gdbarch, ax, value, data, size); |
0d53c4c4 DJ |
2015 | } |
2016 | ||
2017 | /* The set of location functions used with the DWARF-2 expression | |
2018 | evaluator and location lists. */ | |
768a979c | 2019 | const struct symbol_computed_ops dwarf2_loclist_funcs = { |
0d53c4c4 DJ |
2020 | loclist_read_variable, |
2021 | loclist_read_needs_frame, | |
2022 | loclist_describe_location, | |
2023 | loclist_tracepoint_var_ref | |
2024 | }; |