1 /* DWARF 2 location expression support for GDB.
3 Copyright (C) 2003-2020 Free Software Foundation, Inc.
5 Contributed by Daniel Jacobowitz, MontaVista Software, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
35 #include "complaints.h"
37 #include "dwarf2/expr.h"
38 #include "dwarf2/loc.h"
39 #include "dwarf2/read.h"
40 #include "dwarf2/frame.h"
41 #include "dwarf2/leb.h"
42 #include "compile/compile.h"
43 #include "gdbsupport/selftest.h"
46 #include <unordered_set>
47 #include "gdbsupport/underlying.h"
48 #include "gdbsupport/byte-vector.h"
50 static struct value
*dwarf2_evaluate_loc_desc_full (struct type
*type
,
51 struct frame_info
*frame
,
54 struct dwarf2_per_cu_data
*per_cu
,
55 struct type
*subobj_type
,
56 LONGEST subobj_byte_offset
);
58 static struct call_site_parameter
*dwarf_expr_reg_to_entry_parameter
59 (struct frame_info
*frame
,
60 enum call_site_parameter_kind kind
,
61 union call_site_parameter_u kind_u
,
62 struct dwarf2_per_cu_data
**per_cu_return
);
64 static struct value
*indirect_synthetic_pointer
65 (sect_offset die
, LONGEST byte_offset
,
66 struct dwarf2_per_cu_data
*per_cu
,
67 struct frame_info
*frame
,
68 struct type
*type
, bool resolve_abstract_p
= false);
70 /* Until these have formal names, we define these here.
71 ref: http://gcc.gnu.org/wiki/DebugFission
72 Each entry in .debug_loc.dwo begins with a byte that describes the entry,
73 and is then followed by data specific to that entry. */
77 /* Indicates the end of the list of entries. */
78 DEBUG_LOC_END_OF_LIST
= 0,
80 /* This is followed by an unsigned LEB128 number that is an index into
81 .debug_addr and specifies the base address for all following entries. */
82 DEBUG_LOC_BASE_ADDRESS
= 1,
84 /* This is followed by two unsigned LEB128 numbers that are indices into
85 .debug_addr and specify the beginning and ending addresses, and then
86 a normal location expression as in .debug_loc. */
87 DEBUG_LOC_START_END
= 2,
89 /* This is followed by an unsigned LEB128 number that is an index into
90 .debug_addr and specifies the beginning address, and a 4 byte unsigned
91 number that specifies the length, and then a normal location expression
93 DEBUG_LOC_START_LENGTH
= 3,
95 /* This is followed by two unsigned LEB128 operands. The values of these
96 operands are the starting and ending offsets, respectively, relative to
97 the applicable base address. */
98 DEBUG_LOC_OFFSET_PAIR
= 4,
100 /* An internal value indicating there is insufficient data. */
101 DEBUG_LOC_BUFFER_OVERFLOW
= -1,
103 /* An internal value indicating an invalid kind of entry was found. */
104 DEBUG_LOC_INVALID_ENTRY
= -2
107 /* Helper function which throws an error if a synthetic pointer is
111 invalid_synthetic_pointer (void)
113 error (_("access outside bounds of object "
114 "referenced via synthetic pointer"));
117 /* Decode the addresses in a non-dwo .debug_loc entry.
118 A pointer to the next byte to examine is returned in *NEW_PTR.
119 The encoded low,high addresses are return in *LOW,*HIGH.
120 The result indicates the kind of entry found. */
122 static enum debug_loc_kind
123 decode_debug_loc_addresses (const gdb_byte
*loc_ptr
, const gdb_byte
*buf_end
,
124 const gdb_byte
**new_ptr
,
125 CORE_ADDR
*low
, CORE_ADDR
*high
,
126 enum bfd_endian byte_order
,
127 unsigned int addr_size
,
130 CORE_ADDR base_mask
= ~(~(CORE_ADDR
)1 << (addr_size
* 8 - 1));
132 if (buf_end
- loc_ptr
< 2 * addr_size
)
133 return DEBUG_LOC_BUFFER_OVERFLOW
;
136 *low
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
138 *low
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
139 loc_ptr
+= addr_size
;
142 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
144 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
145 loc_ptr
+= addr_size
;
149 /* A base-address-selection entry. */
150 if ((*low
& base_mask
) == base_mask
)
151 return DEBUG_LOC_BASE_ADDRESS
;
153 /* An end-of-list entry. */
154 if (*low
== 0 && *high
== 0)
155 return DEBUG_LOC_END_OF_LIST
;
157 return DEBUG_LOC_START_END
;
160 /* Decode the addresses in .debug_loclists entry.
161 A pointer to the next byte to examine is returned in *NEW_PTR.
162 The encoded low,high addresses are return in *LOW,*HIGH.
163 The result indicates the kind of entry found. */
165 static enum debug_loc_kind
166 decode_debug_loclists_addresses (dwarf2_per_cu_data
*per_cu
,
167 dwarf2_per_objfile
*per_objfile
,
168 const gdb_byte
*loc_ptr
,
169 const gdb_byte
*buf_end
,
170 const gdb_byte
**new_ptr
,
171 CORE_ADDR
*low
, CORE_ADDR
*high
,
172 enum bfd_endian byte_order
,
173 unsigned int addr_size
,
178 if (loc_ptr
== buf_end
)
179 return DEBUG_LOC_BUFFER_OVERFLOW
;
183 case DW_LLE_base_addressx
:
185 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
187 return DEBUG_LOC_BUFFER_OVERFLOW
;
188 *high
= dwarf2_read_addr_index (per_cu
, per_objfile
, u64
);
190 return DEBUG_LOC_BASE_ADDRESS
;
191 case DW_LLE_startx_length
:
192 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
194 return DEBUG_LOC_BUFFER_OVERFLOW
;
195 *low
= dwarf2_read_addr_index (per_cu
, per_objfile
, u64
);
197 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
199 return DEBUG_LOC_BUFFER_OVERFLOW
;
202 return DEBUG_LOC_START_LENGTH
;
203 case DW_LLE_start_length
:
204 if (buf_end
- loc_ptr
< addr_size
)
205 return DEBUG_LOC_BUFFER_OVERFLOW
;
207 *low
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
209 *low
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
210 loc_ptr
+= addr_size
;
212 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
214 return DEBUG_LOC_BUFFER_OVERFLOW
;
217 return DEBUG_LOC_START_LENGTH
;
218 case DW_LLE_end_of_list
:
220 return DEBUG_LOC_END_OF_LIST
;
221 case DW_LLE_base_address
:
222 if (loc_ptr
+ addr_size
> buf_end
)
223 return DEBUG_LOC_BUFFER_OVERFLOW
;
225 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
227 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
228 loc_ptr
+= addr_size
;
230 return DEBUG_LOC_BASE_ADDRESS
;
231 case DW_LLE_offset_pair
:
232 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
234 return DEBUG_LOC_BUFFER_OVERFLOW
;
236 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
238 return DEBUG_LOC_BUFFER_OVERFLOW
;
241 return DEBUG_LOC_OFFSET_PAIR
;
242 /* Following cases are not supported yet. */
243 case DW_LLE_startx_endx
:
244 case DW_LLE_start_end
:
245 case DW_LLE_default_location
:
247 return DEBUG_LOC_INVALID_ENTRY
;
251 /* Decode the addresses in .debug_loc.dwo entry.
252 A pointer to the next byte to examine is returned in *NEW_PTR.
253 The encoded low,high addresses are return in *LOW,*HIGH.
254 The result indicates the kind of entry found. */
256 static enum debug_loc_kind
257 decode_debug_loc_dwo_addresses (dwarf2_per_cu_data
*per_cu
,
258 dwarf2_per_objfile
*per_objfile
,
259 const gdb_byte
*loc_ptr
,
260 const gdb_byte
*buf_end
,
261 const gdb_byte
**new_ptr
,
262 CORE_ADDR
*low
, CORE_ADDR
*high
,
263 enum bfd_endian byte_order
)
265 uint64_t low_index
, high_index
;
267 if (loc_ptr
== buf_end
)
268 return DEBUG_LOC_BUFFER_OVERFLOW
;
272 case DW_LLE_GNU_end_of_list_entry
:
274 return DEBUG_LOC_END_OF_LIST
;
275 case DW_LLE_GNU_base_address_selection_entry
:
277 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
279 return DEBUG_LOC_BUFFER_OVERFLOW
;
280 *high
= dwarf2_read_addr_index (per_cu
, per_objfile
, high_index
);
282 return DEBUG_LOC_BASE_ADDRESS
;
283 case DW_LLE_GNU_start_end_entry
:
284 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
286 return DEBUG_LOC_BUFFER_OVERFLOW
;
287 *low
= dwarf2_read_addr_index (per_cu
, per_objfile
, low_index
);
288 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
290 return DEBUG_LOC_BUFFER_OVERFLOW
;
291 *high
= dwarf2_read_addr_index (per_cu
, per_objfile
, high_index
);
293 return DEBUG_LOC_START_END
;
294 case DW_LLE_GNU_start_length_entry
:
295 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
297 return DEBUG_LOC_BUFFER_OVERFLOW
;
298 *low
= dwarf2_read_addr_index (per_cu
, per_objfile
, low_index
);
299 if (loc_ptr
+ 4 > buf_end
)
300 return DEBUG_LOC_BUFFER_OVERFLOW
;
302 *high
+= extract_unsigned_integer (loc_ptr
, 4, byte_order
);
303 *new_ptr
= loc_ptr
+ 4;
304 return DEBUG_LOC_START_LENGTH
;
306 return DEBUG_LOC_INVALID_ENTRY
;
310 /* A function for dealing with location lists. Given a
311 symbol baton (BATON) and a pc value (PC), find the appropriate
312 location expression, set *LOCEXPR_LENGTH, and return a pointer
313 to the beginning of the expression. Returns NULL on failure.
315 For now, only return the first matching location expression; there
316 can be more than one in the list. */
319 dwarf2_find_location_expression (struct dwarf2_loclist_baton
*baton
,
320 size_t *locexpr_length
, CORE_ADDR pc
)
322 dwarf2_per_objfile
*per_objfile
= baton
->per_objfile
;
323 struct objfile
*objfile
= per_objfile
->objfile
;
324 struct gdbarch
*gdbarch
= objfile
->arch ();
325 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
326 unsigned int addr_size
= baton
->per_cu
->addr_size ();
327 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
328 /* Adjust base_address for relocatable objects. */
329 CORE_ADDR base_offset
= baton
->per_objfile
->objfile
->text_section_offset ();
330 CORE_ADDR base_address
= baton
->base_address
+ base_offset
;
331 const gdb_byte
*loc_ptr
, *buf_end
;
333 loc_ptr
= baton
->data
;
334 buf_end
= baton
->data
+ baton
->size
;
338 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
340 enum debug_loc_kind kind
;
341 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
343 if (baton
->per_cu
->version () < 5 && baton
->from_dwo
)
344 kind
= decode_debug_loc_dwo_addresses (baton
->per_cu
,
346 loc_ptr
, buf_end
, &new_ptr
,
347 &low
, &high
, byte_order
);
348 else if (baton
->per_cu
->version () < 5)
349 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
351 byte_order
, addr_size
,
354 kind
= decode_debug_loclists_addresses (baton
->per_cu
,
356 loc_ptr
, buf_end
, &new_ptr
,
357 &low
, &high
, byte_order
,
358 addr_size
, signed_addr_p
);
363 case DEBUG_LOC_END_OF_LIST
:
366 case DEBUG_LOC_BASE_ADDRESS
:
367 base_address
= high
+ base_offset
;
369 case DEBUG_LOC_START_END
:
370 case DEBUG_LOC_START_LENGTH
:
371 case DEBUG_LOC_OFFSET_PAIR
:
373 case DEBUG_LOC_BUFFER_OVERFLOW
:
374 case DEBUG_LOC_INVALID_ENTRY
:
375 error (_("dwarf2_find_location_expression: "
376 "Corrupted DWARF expression."));
378 gdb_assert_not_reached ("bad debug_loc_kind");
381 /* Otherwise, a location expression entry.
382 If the entry is from a DWO, don't add base address: the entry is from
383 .debug_addr which already has the DWARF "base address". We still add
384 base_offset in case we're debugging a PIE executable. However, if the
385 entry is DW_LLE_offset_pair from a DWO, add the base address as the
386 operands are offsets relative to the applicable base address. */
387 if (baton
->from_dwo
&& kind
!= DEBUG_LOC_OFFSET_PAIR
)
395 high
+= base_address
;
398 if (baton
->per_cu
->version () < 5)
400 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
405 unsigned int bytes_read
;
407 length
= read_unsigned_leb128 (NULL
, loc_ptr
, &bytes_read
);
408 loc_ptr
+= bytes_read
;
411 if (low
== high
&& pc
== low
)
413 /* This is entry PC record present only at entry point
414 of a function. Verify it is really the function entry point. */
416 const struct block
*pc_block
= block_for_pc (pc
);
417 struct symbol
*pc_func
= NULL
;
420 pc_func
= block_linkage_function (pc_block
);
422 if (pc_func
&& pc
== BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (pc_func
)))
424 *locexpr_length
= length
;
429 if (pc
>= low
&& pc
< high
)
431 *locexpr_length
= length
;
439 /* Implement find_frame_base_location method for LOC_BLOCK functions using
440 DWARF expression for its DW_AT_frame_base. */
443 locexpr_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
444 const gdb_byte
**start
, size_t *length
)
446 struct dwarf2_locexpr_baton
*symbaton
447 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
449 *length
= symbaton
->size
;
450 *start
= symbaton
->data
;
453 /* Implement the struct symbol_block_ops::get_frame_base method for
454 LOC_BLOCK functions using a DWARF expression as its DW_AT_frame_base. */
457 locexpr_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
459 struct gdbarch
*gdbarch
;
461 struct dwarf2_locexpr_baton
*dlbaton
;
462 const gdb_byte
*start
;
464 struct value
*result
;
466 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
467 Thus, it's supposed to provide the find_frame_base_location method as
469 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
471 gdbarch
= get_frame_arch (frame
);
472 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
473 dlbaton
= (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
475 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
476 (framefunc
, get_frame_pc (frame
), &start
, &length
);
477 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
480 /* The DW_AT_frame_base attribute contains a location description which
481 computes the base address itself. However, the call to
482 dwarf2_evaluate_loc_desc returns a value representing a variable at
483 that address. The frame base address is thus this variable's
485 return value_address (result
);
488 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
489 function uses DWARF expression for its DW_AT_frame_base. */
491 const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs
=
493 locexpr_find_frame_base_location
,
494 locexpr_get_frame_base
497 /* Implement find_frame_base_location method for LOC_BLOCK functions using
498 DWARF location list for its DW_AT_frame_base. */
501 loclist_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
502 const gdb_byte
**start
, size_t *length
)
504 struct dwarf2_loclist_baton
*symbaton
505 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
507 *start
= dwarf2_find_location_expression (symbaton
, length
, pc
);
510 /* Implement the struct symbol_block_ops::get_frame_base method for
511 LOC_BLOCK functions using a DWARF location list as its DW_AT_frame_base. */
514 loclist_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
516 struct gdbarch
*gdbarch
;
518 struct dwarf2_loclist_baton
*dlbaton
;
519 const gdb_byte
*start
;
521 struct value
*result
;
523 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
524 Thus, it's supposed to provide the find_frame_base_location method as
526 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
528 gdbarch
= get_frame_arch (frame
);
529 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
530 dlbaton
= (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
532 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
533 (framefunc
, get_frame_pc (frame
), &start
, &length
);
534 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
537 /* The DW_AT_frame_base attribute contains a location description which
538 computes the base address itself. However, the call to
539 dwarf2_evaluate_loc_desc returns a value representing a variable at
540 that address. The frame base address is thus this variable's
542 return value_address (result
);
545 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
546 function uses DWARF location list for its DW_AT_frame_base. */
548 const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs
=
550 loclist_find_frame_base_location
,
551 loclist_get_frame_base
554 /* See dwarf2loc.h. */
557 func_get_frame_base_dwarf_block (struct symbol
*framefunc
, CORE_ADDR pc
,
558 const gdb_byte
**start
, size_t *length
)
560 if (SYMBOL_BLOCK_OPS (framefunc
) != NULL
)
562 const struct symbol_block_ops
*ops_block
= SYMBOL_BLOCK_OPS (framefunc
);
564 ops_block
->find_frame_base_location (framefunc
, pc
, start
, length
);
570 error (_("Could not find the frame base for \"%s\"."),
571 framefunc
->natural_name ());
575 get_frame_pc_for_per_cu_dwarf_call (void *baton
)
577 dwarf_expr_context
*ctx
= (dwarf_expr_context
*) baton
;
579 return ctx
->get_frame_pc ();
583 per_cu_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
,
584 struct dwarf2_per_cu_data
*per_cu
)
586 struct dwarf2_locexpr_baton block
;
588 block
= dwarf2_fetch_die_loc_cu_off (die_offset
, per_cu
,
589 get_frame_pc_for_per_cu_dwarf_call
,
592 /* DW_OP_call_ref is currently not supported. */
593 gdb_assert (block
.per_cu
== per_cu
);
595 ctx
->eval (block
.data
, block
.size
);
598 /* Given context CTX, section offset SECT_OFF, and compilation unit
599 data PER_CU, execute the "variable value" operation on the DIE
600 found at SECT_OFF. */
602 static struct value
*
603 sect_variable_value (struct dwarf_expr_context
*ctx
, sect_offset sect_off
,
604 struct dwarf2_per_cu_data
*per_cu
)
606 struct type
*die_type
= dwarf2_fetch_die_type_sect_off (sect_off
, per_cu
);
608 if (die_type
== NULL
)
609 error (_("Bad DW_OP_GNU_variable_value DIE."));
611 /* Note: Things still work when the following test is removed. This
612 test and error is here to conform to the proposed specification. */
613 if (die_type
->code () != TYPE_CODE_INT
614 && die_type
->code () != TYPE_CODE_PTR
)
615 error (_("Type of DW_OP_GNU_variable_value DIE must be an integer or pointer."));
617 struct type
*type
= lookup_pointer_type (die_type
);
618 struct frame_info
*frame
= get_selected_frame (_("No frame selected."));
619 return indirect_synthetic_pointer (sect_off
, 0, per_cu
, frame
, type
, true);
622 class dwarf_evaluate_loc_desc
: public dwarf_expr_context
625 dwarf_evaluate_loc_desc (dwarf2_per_objfile
*per_objfile
)
626 : dwarf_expr_context (per_objfile
)
629 struct frame_info
*frame
;
630 struct dwarf2_per_cu_data
*per_cu
;
631 CORE_ADDR obj_address
;
633 /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for
634 the frame in BATON. */
636 CORE_ADDR
get_frame_cfa () override
638 return dwarf2_frame_cfa (frame
);
641 /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for
642 the frame in BATON. */
644 CORE_ADDR
get_frame_pc () override
646 return get_frame_address_in_block (frame
);
649 /* Using the objfile specified in BATON, find the address for the
650 current thread's thread-local storage with offset OFFSET. */
651 CORE_ADDR
get_tls_address (CORE_ADDR offset
) override
653 struct objfile
*objfile
= per_cu
->objfile ();
655 return target_translate_tls_address (objfile
, offset
);
658 /* Helper interface of per_cu_dwarf_call for
659 dwarf2_evaluate_loc_desc. */
661 void dwarf_call (cu_offset die_offset
) override
663 per_cu_dwarf_call (this, die_offset
, per_cu
);
666 /* Helper interface of sect_variable_value for
667 dwarf2_evaluate_loc_desc. */
669 struct value
*dwarf_variable_value (sect_offset sect_off
) override
671 return sect_variable_value (this, sect_off
, per_cu
);
674 struct type
*get_base_type (cu_offset die_offset
, int size
) override
676 struct type
*result
= dwarf2_get_die_type (die_offset
, per_cu
);
678 error (_("Could not find type for DW_OP_const_type"));
679 if (size
!= 0 && TYPE_LENGTH (result
) != size
)
680 error (_("DW_OP_const_type has different sizes for type and data"));
684 /* Callback function for dwarf2_evaluate_loc_desc.
685 Fetch the address indexed by DW_OP_addrx or DW_OP_GNU_addr_index. */
687 CORE_ADDR
get_addr_index (unsigned int index
) override
689 return dwarf2_read_addr_index (per_cu
, per_objfile
, index
);
692 /* Callback function for get_object_address. Return the address of the VLA
695 CORE_ADDR
get_object_address () override
697 if (obj_address
== 0)
698 error (_("Location address is not set."));
702 /* Execute DWARF block of call_site_parameter which matches KIND and
703 KIND_U. Choose DEREF_SIZE value of that parameter. Search
704 caller of this objects's frame.
706 The caller can be from a different CU - per_cu_dwarf_call
707 implementation can be more simple as it does not support cross-CU
710 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
711 union call_site_parameter_u kind_u
,
712 int deref_size
) override
714 struct frame_info
*caller_frame
;
715 struct dwarf2_per_cu_data
*caller_per_cu
;
716 struct call_site_parameter
*parameter
;
717 const gdb_byte
*data_src
;
720 caller_frame
= get_prev_frame (frame
);
722 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
724 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
725 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
727 /* DEREF_SIZE size is not verified here. */
728 if (data_src
== NULL
)
729 throw_error (NO_ENTRY_VALUE_ERROR
,
730 _("Cannot resolve DW_AT_call_data_value"));
732 scoped_restore save_frame
= make_scoped_restore (&this->frame
,
734 scoped_restore save_per_cu
= make_scoped_restore (&this->per_cu
,
736 scoped_restore save_obj_addr
= make_scoped_restore (&this->obj_address
,
739 scoped_restore save_arch
= make_scoped_restore (&this->gdbarch
);
740 this->gdbarch
= per_cu
->objfile ()->arch ();
741 scoped_restore save_addr_size
= make_scoped_restore (&this->addr_size
);
742 this->addr_size
= per_cu
->addr_size ();
744 this->eval (data_src
, size
);
747 /* Using the frame specified in BATON, find the location expression
748 describing the frame base. Return a pointer to it in START and
749 its length in LENGTH. */
750 void get_frame_base (const gdb_byte
**start
, size_t * length
) override
752 /* FIXME: cagney/2003-03-26: This code should be using
753 get_frame_base_address(), and then implement a dwarf2 specific
755 struct symbol
*framefunc
;
756 const struct block
*bl
= get_frame_block (frame
, NULL
);
759 error (_("frame address is not available."));
761 /* Use block_linkage_function, which returns a real (not inlined)
762 function, instead of get_frame_function, which may return an
764 framefunc
= block_linkage_function (bl
);
766 /* If we found a frame-relative symbol then it was certainly within
767 some function associated with a frame. If we can't find the frame,
768 something has gone wrong. */
769 gdb_assert (framefunc
!= NULL
);
771 func_get_frame_base_dwarf_block (framefunc
,
772 get_frame_address_in_block (frame
),
776 /* Read memory at ADDR (length LEN) into BUF. */
778 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) override
780 read_memory (addr
, buf
, len
);
783 /* Using the frame specified in BATON, return the value of register
784 REGNUM, treated as a pointer. */
785 CORE_ADDR
read_addr_from_reg (int dwarf_regnum
) override
787 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
788 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
790 return address_from_register (regnum
, frame
);
793 /* Implement "get_reg_value" callback. */
795 struct value
*get_reg_value (struct type
*type
, int dwarf_regnum
) override
797 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
798 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
800 return value_from_register (type
, regnum
, frame
);
804 /* See dwarf2loc.h. */
806 unsigned int entry_values_debug
= 0;
808 /* Helper to set entry_values_debug. */
811 show_entry_values_debug (struct ui_file
*file
, int from_tty
,
812 struct cmd_list_element
*c
, const char *value
)
814 fprintf_filtered (file
,
815 _("Entry values and tail call frames debugging is %s.\n"),
819 /* Find DW_TAG_call_site's DW_AT_call_target address.
820 CALLER_FRAME (for registers) can be NULL if it is not known. This function
821 always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */
824 call_site_to_target_addr (struct gdbarch
*call_site_gdbarch
,
825 struct call_site
*call_site
,
826 struct frame_info
*caller_frame
)
828 switch (FIELD_LOC_KIND (call_site
->target
))
830 case FIELD_LOC_KIND_DWARF_BLOCK
:
832 struct dwarf2_locexpr_baton
*dwarf_block
;
834 struct type
*caller_core_addr_type
;
835 struct gdbarch
*caller_arch
;
837 dwarf_block
= FIELD_DWARF_BLOCK (call_site
->target
);
838 if (dwarf_block
== NULL
)
840 struct bound_minimal_symbol msym
;
842 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
843 throw_error (NO_ENTRY_VALUE_ERROR
,
844 _("DW_AT_call_target is not specified at %s in %s"),
845 paddress (call_site_gdbarch
, call_site
->pc
),
846 (msym
.minsym
== NULL
? "???"
847 : msym
.minsym
->print_name ()));
850 if (caller_frame
== NULL
)
852 struct bound_minimal_symbol msym
;
854 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
855 throw_error (NO_ENTRY_VALUE_ERROR
,
856 _("DW_AT_call_target DWARF block resolving "
857 "requires known frame which is currently not "
858 "available at %s in %s"),
859 paddress (call_site_gdbarch
, call_site
->pc
),
860 (msym
.minsym
== NULL
? "???"
861 : msym
.minsym
->print_name ()));
864 caller_arch
= get_frame_arch (caller_frame
);
865 caller_core_addr_type
= builtin_type (caller_arch
)->builtin_func_ptr
;
866 val
= dwarf2_evaluate_loc_desc (caller_core_addr_type
, caller_frame
,
867 dwarf_block
->data
, dwarf_block
->size
,
868 dwarf_block
->per_cu
);
869 /* DW_AT_call_target is a DWARF expression, not a DWARF location. */
870 if (VALUE_LVAL (val
) == lval_memory
)
871 return value_address (val
);
873 return value_as_address (val
);
876 case FIELD_LOC_KIND_PHYSNAME
:
878 const char *physname
;
879 struct bound_minimal_symbol msym
;
881 physname
= FIELD_STATIC_PHYSNAME (call_site
->target
);
883 /* Handle both the mangled and demangled PHYSNAME. */
884 msym
= lookup_minimal_symbol (physname
, NULL
, NULL
);
885 if (msym
.minsym
== NULL
)
887 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
888 throw_error (NO_ENTRY_VALUE_ERROR
,
889 _("Cannot find function \"%s\" for a call site target "
891 physname
, paddress (call_site_gdbarch
, call_site
->pc
),
892 (msym
.minsym
== NULL
? "???"
893 : msym
.minsym
->print_name ()));
896 return BMSYMBOL_VALUE_ADDRESS (msym
);
899 case FIELD_LOC_KIND_PHYSADDR
:
900 return FIELD_STATIC_PHYSADDR (call_site
->target
);
903 internal_error (__FILE__
, __LINE__
, _("invalid call site target kind"));
907 /* Convert function entry point exact address ADDR to the function which is
908 compliant with TAIL_CALL_LIST_COMPLETE condition. Throw
909 NO_ENTRY_VALUE_ERROR otherwise. */
911 static struct symbol
*
912 func_addr_to_tail_call_list (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
914 struct symbol
*sym
= find_pc_function (addr
);
917 if (sym
== NULL
|| BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (sym
)) != addr
)
918 throw_error (NO_ENTRY_VALUE_ERROR
,
919 _("DW_TAG_call_site resolving failed to find function "
920 "name for address %s"),
921 paddress (gdbarch
, addr
));
923 type
= SYMBOL_TYPE (sym
);
924 gdb_assert (type
->code () == TYPE_CODE_FUNC
);
925 gdb_assert (TYPE_SPECIFIC_FIELD (type
) == TYPE_SPECIFIC_FUNC
);
930 /* Verify function with entry point exact address ADDR can never call itself
931 via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it
932 can call itself via tail calls.
934 If a funtion can tail call itself its entry value based parameters are
935 unreliable. There is no verification whether the value of some/all
936 parameters is unchanged through the self tail call, we expect if there is
937 a self tail call all the parameters can be modified. */
940 func_verify_no_selftailcall (struct gdbarch
*gdbarch
, CORE_ADDR verify_addr
)
944 /* The verification is completely unordered. Track here function addresses
945 which still need to be iterated. */
946 std::vector
<CORE_ADDR
> todo
;
948 /* Track here CORE_ADDRs which were already visited. */
949 std::unordered_set
<CORE_ADDR
> addr_hash
;
951 todo
.push_back (verify_addr
);
952 while (!todo
.empty ())
954 struct symbol
*func_sym
;
955 struct call_site
*call_site
;
960 func_sym
= func_addr_to_tail_call_list (gdbarch
, addr
);
962 for (call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym
));
963 call_site
; call_site
= call_site
->tail_call_next
)
965 CORE_ADDR target_addr
;
967 /* CALLER_FRAME with registers is not available for tail-call jumped
969 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
971 if (target_addr
== verify_addr
)
973 struct bound_minimal_symbol msym
;
975 msym
= lookup_minimal_symbol_by_pc (verify_addr
);
976 throw_error (NO_ENTRY_VALUE_ERROR
,
977 _("DW_OP_entry_value resolving has found "
978 "function \"%s\" at %s can call itself via tail "
980 (msym
.minsym
== NULL
? "???"
981 : msym
.minsym
->print_name ()),
982 paddress (gdbarch
, verify_addr
));
985 if (addr_hash
.insert (target_addr
).second
)
986 todo
.push_back (target_addr
);
991 /* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for
992 ENTRY_VALUES_DEBUG. */
995 tailcall_dump (struct gdbarch
*gdbarch
, const struct call_site
*call_site
)
997 CORE_ADDR addr
= call_site
->pc
;
998 struct bound_minimal_symbol msym
= lookup_minimal_symbol_by_pc (addr
- 1);
1000 fprintf_unfiltered (gdb_stdlog
, " %s(%s)", paddress (gdbarch
, addr
),
1001 (msym
.minsym
== NULL
? "???"
1002 : msym
.minsym
->print_name ()));
1006 /* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP
1007 only top callers and bottom callees which are present in both. GDBARCH is
1008 used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are
1009 no remaining possibilities to provide unambiguous non-trivial result.
1010 RESULTP should point to NULL on the first (initialization) call. Caller is
1011 responsible for xfree of any RESULTP data. */
1014 chain_candidate (struct gdbarch
*gdbarch
,
1015 gdb::unique_xmalloc_ptr
<struct call_site_chain
> *resultp
,
1016 std::vector
<struct call_site
*> *chain
)
1018 long length
= chain
->size ();
1019 int callers
, callees
, idx
;
1021 if (*resultp
== NULL
)
1023 /* Create the initial chain containing all the passed PCs. */
1025 struct call_site_chain
*result
1026 = ((struct call_site_chain
*)
1027 xmalloc (sizeof (*result
)
1028 + sizeof (*result
->call_site
) * (length
- 1)));
1029 result
->length
= length
;
1030 result
->callers
= result
->callees
= length
;
1031 if (!chain
->empty ())
1032 memcpy (result
->call_site
, chain
->data (),
1033 sizeof (*result
->call_site
) * length
);
1034 resultp
->reset (result
);
1036 if (entry_values_debug
)
1038 fprintf_unfiltered (gdb_stdlog
, "tailcall: initial:");
1039 for (idx
= 0; idx
< length
; idx
++)
1040 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
1041 fputc_unfiltered ('\n', gdb_stdlog
);
1047 if (entry_values_debug
)
1049 fprintf_unfiltered (gdb_stdlog
, "tailcall: compare:");
1050 for (idx
= 0; idx
< length
; idx
++)
1051 tailcall_dump (gdbarch
, chain
->at (idx
));
1052 fputc_unfiltered ('\n', gdb_stdlog
);
1055 /* Intersect callers. */
1057 callers
= std::min ((long) (*resultp
)->callers
, length
);
1058 for (idx
= 0; idx
< callers
; idx
++)
1059 if ((*resultp
)->call_site
[idx
] != chain
->at (idx
))
1061 (*resultp
)->callers
= idx
;
1065 /* Intersect callees. */
1067 callees
= std::min ((long) (*resultp
)->callees
, length
);
1068 for (idx
= 0; idx
< callees
; idx
++)
1069 if ((*resultp
)->call_site
[(*resultp
)->length
- 1 - idx
]
1070 != chain
->at (length
- 1 - idx
))
1072 (*resultp
)->callees
= idx
;
1076 if (entry_values_debug
)
1078 fprintf_unfiltered (gdb_stdlog
, "tailcall: reduced:");
1079 for (idx
= 0; idx
< (*resultp
)->callers
; idx
++)
1080 tailcall_dump (gdbarch
, (*resultp
)->call_site
[idx
]);
1081 fputs_unfiltered (" |", gdb_stdlog
);
1082 for (idx
= 0; idx
< (*resultp
)->callees
; idx
++)
1083 tailcall_dump (gdbarch
,
1084 (*resultp
)->call_site
[(*resultp
)->length
1085 - (*resultp
)->callees
+ idx
]);
1086 fputc_unfiltered ('\n', gdb_stdlog
);
1089 if ((*resultp
)->callers
== 0 && (*resultp
)->callees
== 0)
1091 /* There are no common callers or callees. It could be also a direct
1092 call (which has length 0) with ambiguous possibility of an indirect
1093 call - CALLERS == CALLEES == 0 is valid during the first allocation
1094 but any subsequence processing of such entry means ambiguity. */
1095 resultp
->reset (NULL
);
1099 /* See call_site_find_chain_1 why there is no way to reach the bottom callee
1100 PC again. In such case there must be two different code paths to reach
1101 it. CALLERS + CALLEES equal to LENGTH in the case of self tail-call. */
1102 gdb_assert ((*resultp
)->callers
+ (*resultp
)->callees
<= (*resultp
)->length
);
1105 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1106 assumed frames between them use GDBARCH. Use depth first search so we can
1107 keep single CHAIN of call_site's back to CALLER_PC. Function recursion
1108 would have needless GDB stack overhead. Any unreliability results
1109 in thrown NO_ENTRY_VALUE_ERROR. */
1111 static gdb::unique_xmalloc_ptr
<call_site_chain
>
1112 call_site_find_chain_1 (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1113 CORE_ADDR callee_pc
)
1115 CORE_ADDR save_callee_pc
= callee_pc
;
1116 gdb::unique_xmalloc_ptr
<struct call_site_chain
> retval
;
1117 struct call_site
*call_site
;
1119 /* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's
1120 call_site nor any possible call_site at CALLEE_PC's function is there.
1121 Any CALL_SITE in CHAIN will be iterated to its siblings - via
1122 TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */
1123 std::vector
<struct call_site
*> chain
;
1125 /* We are not interested in the specific PC inside the callee function. */
1126 callee_pc
= get_pc_function_start (callee_pc
);
1128 throw_error (NO_ENTRY_VALUE_ERROR
, _("Unable to find function for PC %s"),
1129 paddress (gdbarch
, save_callee_pc
));
1131 /* Mark CALL_SITEs so we do not visit the same ones twice. */
1132 std::unordered_set
<CORE_ADDR
> addr_hash
;
1134 /* Do not push CALL_SITE to CHAIN. Push there only the first tail call site
1135 at the target's function. All the possible tail call sites in the
1136 target's function will get iterated as already pushed into CHAIN via their
1138 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1142 CORE_ADDR target_func_addr
;
1143 struct call_site
*target_call_site
;
1145 /* CALLER_FRAME with registers is not available for tail-call jumped
1147 target_func_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
1149 if (target_func_addr
== callee_pc
)
1151 chain_candidate (gdbarch
, &retval
, &chain
);
1155 /* There is no way to reach CALLEE_PC again as we would prevent
1156 entering it twice as being already marked in ADDR_HASH. */
1157 target_call_site
= NULL
;
1161 struct symbol
*target_func
;
1163 target_func
= func_addr_to_tail_call_list (gdbarch
, target_func_addr
);
1164 target_call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func
));
1169 /* Attempt to visit TARGET_CALL_SITE. */
1171 if (target_call_site
)
1173 if (addr_hash
.insert (target_call_site
->pc
).second
)
1175 /* Successfully entered TARGET_CALL_SITE. */
1177 chain
.push_back (target_call_site
);
1182 /* Backtrack (without revisiting the originating call_site). Try the
1183 callers's sibling; if there isn't any try the callers's callers's
1186 target_call_site
= NULL
;
1187 while (!chain
.empty ())
1189 call_site
= chain
.back ();
1192 size_t removed
= addr_hash
.erase (call_site
->pc
);
1193 gdb_assert (removed
== 1);
1195 target_call_site
= call_site
->tail_call_next
;
1196 if (target_call_site
)
1200 while (target_call_site
);
1205 call_site
= chain
.back ();
1210 struct bound_minimal_symbol msym_caller
, msym_callee
;
1212 msym_caller
= lookup_minimal_symbol_by_pc (caller_pc
);
1213 msym_callee
= lookup_minimal_symbol_by_pc (callee_pc
);
1214 throw_error (NO_ENTRY_VALUE_ERROR
,
1215 _("There are no unambiguously determinable intermediate "
1216 "callers or callees between caller function \"%s\" at %s "
1217 "and callee function \"%s\" at %s"),
1218 (msym_caller
.minsym
== NULL
1219 ? "???" : msym_caller
.minsym
->print_name ()),
1220 paddress (gdbarch
, caller_pc
),
1221 (msym_callee
.minsym
== NULL
1222 ? "???" : msym_callee
.minsym
->print_name ()),
1223 paddress (gdbarch
, callee_pc
));
1229 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1230 assumed frames between them use GDBARCH. If valid call_site_chain cannot be
1231 constructed return NULL. */
1233 gdb::unique_xmalloc_ptr
<call_site_chain
>
1234 call_site_find_chain (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1235 CORE_ADDR callee_pc
)
1237 gdb::unique_xmalloc_ptr
<call_site_chain
> retval
;
1241 retval
= call_site_find_chain_1 (gdbarch
, caller_pc
, callee_pc
);
1243 catch (const gdb_exception_error
&e
)
1245 if (e
.error
== NO_ENTRY_VALUE_ERROR
)
1247 if (entry_values_debug
)
1248 exception_print (gdb_stdout
, e
);
1259 /* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */
1262 call_site_parameter_matches (struct call_site_parameter
*parameter
,
1263 enum call_site_parameter_kind kind
,
1264 union call_site_parameter_u kind_u
)
1266 if (kind
== parameter
->kind
)
1269 case CALL_SITE_PARAMETER_DWARF_REG
:
1270 return kind_u
.dwarf_reg
== parameter
->u
.dwarf_reg
;
1271 case CALL_SITE_PARAMETER_FB_OFFSET
:
1272 return kind_u
.fb_offset
== parameter
->u
.fb_offset
;
1273 case CALL_SITE_PARAMETER_PARAM_OFFSET
:
1274 return kind_u
.param_cu_off
== parameter
->u
.param_cu_off
;
1279 /* Fetch call_site_parameter from caller matching KIND and KIND_U.
1280 FRAME is for callee.
1282 Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
1285 static struct call_site_parameter
*
1286 dwarf_expr_reg_to_entry_parameter (struct frame_info
*frame
,
1287 enum call_site_parameter_kind kind
,
1288 union call_site_parameter_u kind_u
,
1289 struct dwarf2_per_cu_data
**per_cu_return
)
1291 CORE_ADDR func_addr
, caller_pc
;
1292 struct gdbarch
*gdbarch
;
1293 struct frame_info
*caller_frame
;
1294 struct call_site
*call_site
;
1296 /* Initialize it just to avoid a GCC false warning. */
1297 struct call_site_parameter
*parameter
= NULL
;
1298 CORE_ADDR target_addr
;
1300 while (get_frame_type (frame
) == INLINE_FRAME
)
1302 frame
= get_prev_frame (frame
);
1303 gdb_assert (frame
!= NULL
);
1306 func_addr
= get_frame_func (frame
);
1307 gdbarch
= get_frame_arch (frame
);
1308 caller_frame
= get_prev_frame (frame
);
1309 if (gdbarch
!= frame_unwind_arch (frame
))
1311 struct bound_minimal_symbol msym
1312 = lookup_minimal_symbol_by_pc (func_addr
);
1313 struct gdbarch
*caller_gdbarch
= frame_unwind_arch (frame
);
1315 throw_error (NO_ENTRY_VALUE_ERROR
,
1316 _("DW_OP_entry_value resolving callee gdbarch %s "
1317 "(of %s (%s)) does not match caller gdbarch %s"),
1318 gdbarch_bfd_arch_info (gdbarch
)->printable_name
,
1319 paddress (gdbarch
, func_addr
),
1320 (msym
.minsym
== NULL
? "???"
1321 : msym
.minsym
->print_name ()),
1322 gdbarch_bfd_arch_info (caller_gdbarch
)->printable_name
);
1325 if (caller_frame
== NULL
)
1327 struct bound_minimal_symbol msym
1328 = lookup_minimal_symbol_by_pc (func_addr
);
1330 throw_error (NO_ENTRY_VALUE_ERROR
, _("DW_OP_entry_value resolving "
1331 "requires caller of %s (%s)"),
1332 paddress (gdbarch
, func_addr
),
1333 (msym
.minsym
== NULL
? "???"
1334 : msym
.minsym
->print_name ()));
1336 caller_pc
= get_frame_pc (caller_frame
);
1337 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1339 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, caller_frame
);
1340 if (target_addr
!= func_addr
)
1342 struct minimal_symbol
*target_msym
, *func_msym
;
1344 target_msym
= lookup_minimal_symbol_by_pc (target_addr
).minsym
;
1345 func_msym
= lookup_minimal_symbol_by_pc (func_addr
).minsym
;
1346 throw_error (NO_ENTRY_VALUE_ERROR
,
1347 _("DW_OP_entry_value resolving expects callee %s at %s "
1348 "but the called frame is for %s at %s"),
1349 (target_msym
== NULL
? "???"
1350 : target_msym
->print_name ()),
1351 paddress (gdbarch
, target_addr
),
1352 func_msym
== NULL
? "???" : func_msym
->print_name (),
1353 paddress (gdbarch
, func_addr
));
1356 /* No entry value based parameters would be reliable if this function can
1357 call itself via tail calls. */
1358 func_verify_no_selftailcall (gdbarch
, func_addr
);
1360 for (iparams
= 0; iparams
< call_site
->parameter_count
; iparams
++)
1362 parameter
= &call_site
->parameter
[iparams
];
1363 if (call_site_parameter_matches (parameter
, kind
, kind_u
))
1366 if (iparams
== call_site
->parameter_count
)
1368 struct minimal_symbol
*msym
1369 = lookup_minimal_symbol_by_pc (caller_pc
).minsym
;
1371 /* DW_TAG_call_site_parameter will be missing just if GCC could not
1372 determine its value. */
1373 throw_error (NO_ENTRY_VALUE_ERROR
, _("Cannot find matching parameter "
1374 "at DW_TAG_call_site %s at %s"),
1375 paddress (gdbarch
, caller_pc
),
1376 msym
== NULL
? "???" : msym
->print_name ());
1379 *per_cu_return
= call_site
->per_cu
;
1383 /* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return
1384 the normal DW_AT_call_value block. Otherwise return the
1385 DW_AT_call_data_value (dereferenced) block.
1387 TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned
1390 Function always returns non-NULL, non-optimized out value. It throws
1391 NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */
1393 static struct value
*
1394 dwarf_entry_parameter_to_value (struct call_site_parameter
*parameter
,
1395 CORE_ADDR deref_size
, struct type
*type
,
1396 struct frame_info
*caller_frame
,
1397 struct dwarf2_per_cu_data
*per_cu
)
1399 const gdb_byte
*data_src
;
1403 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
1404 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
1406 /* DEREF_SIZE size is not verified here. */
1407 if (data_src
== NULL
)
1408 throw_error (NO_ENTRY_VALUE_ERROR
,
1409 _("Cannot resolve DW_AT_call_data_value"));
1411 /* DW_AT_call_value is a DWARF expression, not a DWARF
1412 location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from
1414 data
= (gdb_byte
*) alloca (size
+ 1);
1415 memcpy (data
, data_src
, size
);
1416 data
[size
] = DW_OP_stack_value
;
1418 return dwarf2_evaluate_loc_desc (type
, caller_frame
, data
, size
+ 1, per_cu
);
1421 /* VALUE must be of type lval_computed with entry_data_value_funcs. Perform
1422 the indirect method on it, that is use its stored target value, the sole
1423 purpose of entry_data_value_funcs.. */
1425 static struct value
*
1426 entry_data_value_coerce_ref (const struct value
*value
)
1428 struct type
*checked_type
= check_typedef (value_type (value
));
1429 struct value
*target_val
;
1431 if (!TYPE_IS_REFERENCE (checked_type
))
1434 target_val
= (struct value
*) value_computed_closure (value
);
1435 value_incref (target_val
);
1439 /* Implement copy_closure. */
1442 entry_data_value_copy_closure (const struct value
*v
)
1444 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1446 value_incref (target_val
);
1450 /* Implement free_closure. */
1453 entry_data_value_free_closure (struct value
*v
)
1455 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1457 value_decref (target_val
);
1460 /* Vector for methods for an entry value reference where the referenced value
1461 is stored in the caller. On the first dereference use
1462 DW_AT_call_data_value in the caller. */
1464 static const struct lval_funcs entry_data_value_funcs
=
1468 NULL
, /* indirect */
1469 entry_data_value_coerce_ref
,
1470 NULL
, /* check_synthetic_pointer */
1471 entry_data_value_copy_closure
,
1472 entry_data_value_free_closure
1475 /* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U
1476 are used to match DW_AT_location at the caller's
1477 DW_TAG_call_site_parameter.
1479 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1480 cannot resolve the parameter for any reason. */
1482 static struct value
*
1483 value_of_dwarf_reg_entry (struct type
*type
, struct frame_info
*frame
,
1484 enum call_site_parameter_kind kind
,
1485 union call_site_parameter_u kind_u
)
1487 struct type
*checked_type
= check_typedef (type
);
1488 struct type
*target_type
= TYPE_TARGET_TYPE (checked_type
);
1489 struct frame_info
*caller_frame
= get_prev_frame (frame
);
1490 struct value
*outer_val
, *target_val
, *val
;
1491 struct call_site_parameter
*parameter
;
1492 struct dwarf2_per_cu_data
*caller_per_cu
;
1494 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
1497 outer_val
= dwarf_entry_parameter_to_value (parameter
, -1 /* deref_size */,
1501 /* Check if DW_AT_call_data_value cannot be used. If it should be
1502 used and it is not available do not fall back to OUTER_VAL - dereferencing
1503 TYPE_CODE_REF with non-entry data value would give current value - not the
1506 if (!TYPE_IS_REFERENCE (checked_type
)
1507 || TYPE_TARGET_TYPE (checked_type
) == NULL
)
1510 target_val
= dwarf_entry_parameter_to_value (parameter
,
1511 TYPE_LENGTH (target_type
),
1512 target_type
, caller_frame
,
1515 val
= allocate_computed_value (type
, &entry_data_value_funcs
,
1516 release_value (target_val
).release ());
1518 /* Copy the referencing pointer to the new computed value. */
1519 memcpy (value_contents_raw (val
), value_contents_raw (outer_val
),
1520 TYPE_LENGTH (checked_type
));
1521 set_value_lazy (val
, 0);
1526 /* Read parameter of TYPE at (callee) FRAME's function entry. DATA and
1527 SIZE are DWARF block used to match DW_AT_location at the caller's
1528 DW_TAG_call_site_parameter.
1530 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1531 cannot resolve the parameter for any reason. */
1533 static struct value
*
1534 value_of_dwarf_block_entry (struct type
*type
, struct frame_info
*frame
,
1535 const gdb_byte
*block
, size_t block_len
)
1537 union call_site_parameter_u kind_u
;
1539 kind_u
.dwarf_reg
= dwarf_block_to_dwarf_reg (block
, block
+ block_len
);
1540 if (kind_u
.dwarf_reg
!= -1)
1541 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_DWARF_REG
,
1544 if (dwarf_block_to_fb_offset (block
, block
+ block_len
, &kind_u
.fb_offset
))
1545 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_FB_OFFSET
,
1548 /* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message
1549 suppressed during normal operation. The expression can be arbitrary if
1550 there is no caller-callee entry value binding expected. */
1551 throw_error (NO_ENTRY_VALUE_ERROR
,
1552 _("DWARF-2 expression error: DW_OP_entry_value is supported "
1553 "only for single DW_OP_reg* or for DW_OP_fbreg(*)"));
1556 struct piece_closure
1558 /* Reference count. */
1561 /* The objfile from which this closure's expression came. */
1562 dwarf2_per_objfile
*per_objfile
= nullptr;
1564 /* The CU from which this closure's expression came. */
1565 struct dwarf2_per_cu_data
*per_cu
= NULL
;
1567 /* The pieces describing this variable. */
1568 std::vector
<dwarf_expr_piece
> pieces
;
1570 /* Frame ID of frame to which a register value is relative, used
1571 only by DWARF_VALUE_REGISTER. */
1572 struct frame_id frame_id
;
1575 /* Allocate a closure for a value formed from separately-described
1578 static struct piece_closure
*
1579 allocate_piece_closure (struct dwarf2_per_cu_data
*per_cu
,
1580 std::vector
<dwarf_expr_piece
> &&pieces
,
1581 struct frame_info
*frame
)
1583 struct piece_closure
*c
= new piece_closure
;
1586 /* We must capture this here due to sharing of DWARF state. */
1587 c
->per_objfile
= per_cu
->dwarf2_per_objfile
;
1589 c
->pieces
= std::move (pieces
);
1591 c
->frame_id
= null_frame_id
;
1593 c
->frame_id
= get_frame_id (frame
);
1595 for (dwarf_expr_piece
&piece
: c
->pieces
)
1596 if (piece
.location
== DWARF_VALUE_STACK
)
1597 value_incref (piece
.v
.value
);
1602 /* Return the number of bytes overlapping a contiguous chunk of N_BITS
1603 bits whose first bit is located at bit offset START. */
1606 bits_to_bytes (ULONGEST start
, ULONGEST n_bits
)
1608 return (start
% 8 + n_bits
+ 7) / 8;
1611 /* Read or write a pieced value V. If FROM != NULL, operate in "write
1612 mode": copy FROM into the pieces comprising V. If FROM == NULL,
1613 operate in "read mode": fetch the contents of the (lazy) value V by
1614 composing it from its pieces. */
1617 rw_pieced_value (struct value
*v
, struct value
*from
)
1620 LONGEST offset
= 0, max_offset
;
1621 ULONGEST bits_to_skip
;
1622 gdb_byte
*v_contents
;
1623 const gdb_byte
*from_contents
;
1624 struct piece_closure
*c
1625 = (struct piece_closure
*) value_computed_closure (v
);
1626 gdb::byte_vector buffer
;
1627 bool bits_big_endian
= type_byte_order (value_type (v
)) == BFD_ENDIAN_BIG
;
1631 from_contents
= value_contents (from
);
1636 if (value_type (v
) != value_enclosing_type (v
))
1637 internal_error (__FILE__
, __LINE__
,
1638 _("Should not be able to create a lazy value with "
1639 "an enclosing type"));
1640 v_contents
= value_contents_raw (v
);
1641 from_contents
= NULL
;
1644 bits_to_skip
= 8 * value_offset (v
);
1645 if (value_bitsize (v
))
1647 bits_to_skip
+= (8 * value_offset (value_parent (v
))
1648 + value_bitpos (v
));
1650 && (type_byte_order (value_type (from
))
1653 /* Use the least significant bits of FROM. */
1654 max_offset
= 8 * TYPE_LENGTH (value_type (from
));
1655 offset
= max_offset
- value_bitsize (v
);
1658 max_offset
= value_bitsize (v
);
1661 max_offset
= 8 * TYPE_LENGTH (value_type (v
));
1663 /* Advance to the first non-skipped piece. */
1664 for (i
= 0; i
< c
->pieces
.size () && bits_to_skip
>= c
->pieces
[i
].size
; i
++)
1665 bits_to_skip
-= c
->pieces
[i
].size
;
1667 for (; i
< c
->pieces
.size () && offset
< max_offset
; i
++)
1669 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1670 size_t this_size_bits
, this_size
;
1672 this_size_bits
= p
->size
- bits_to_skip
;
1673 if (this_size_bits
> max_offset
- offset
)
1674 this_size_bits
= max_offset
- offset
;
1676 switch (p
->location
)
1678 case DWARF_VALUE_REGISTER
:
1680 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1681 struct gdbarch
*arch
= get_frame_arch (frame
);
1682 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1683 ULONGEST reg_bits
= 8 * register_size (arch
, gdb_regnum
);
1686 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1687 && p
->offset
+ p
->size
< reg_bits
)
1689 /* Big-endian, and we want less than full size. */
1690 bits_to_skip
+= reg_bits
- (p
->offset
+ p
->size
);
1693 bits_to_skip
+= p
->offset
;
1695 this_size
= bits_to_bytes (bits_to_skip
, this_size_bits
);
1696 buffer
.resize (this_size
);
1701 if (!get_frame_register_bytes (frame
, gdb_regnum
,
1703 this_size
, buffer
.data (),
1707 mark_value_bits_optimized_out (v
, offset
,
1710 mark_value_bits_unavailable (v
, offset
,
1715 copy_bitwise (v_contents
, offset
,
1716 buffer
.data (), bits_to_skip
% 8,
1717 this_size_bits
, bits_big_endian
);
1722 if (bits_to_skip
% 8 != 0 || this_size_bits
% 8 != 0)
1724 /* Data is copied non-byte-aligned into the register.
1725 Need some bits from original register value. */
1726 get_frame_register_bytes (frame
, gdb_regnum
,
1728 this_size
, buffer
.data (),
1731 throw_error (OPTIMIZED_OUT_ERROR
,
1732 _("Can't do read-modify-write to "
1733 "update bitfield; containing word "
1734 "has been optimized out"));
1736 throw_error (NOT_AVAILABLE_ERROR
,
1737 _("Can't do read-modify-write to "
1738 "update bitfield; containing word "
1742 copy_bitwise (buffer
.data (), bits_to_skip
% 8,
1743 from_contents
, offset
,
1744 this_size_bits
, bits_big_endian
);
1745 put_frame_register_bytes (frame
, gdb_regnum
,
1747 this_size
, buffer
.data ());
1752 case DWARF_VALUE_MEMORY
:
1754 bits_to_skip
+= p
->offset
;
1756 CORE_ADDR start_addr
= p
->v
.mem
.addr
+ bits_to_skip
/ 8;
1758 if (bits_to_skip
% 8 == 0 && this_size_bits
% 8 == 0
1761 /* Everything is byte-aligned; no buffer needed. */
1763 write_memory_with_notification (start_addr
,
1766 this_size_bits
/ 8);
1768 read_value_memory (v
, offset
,
1769 p
->v
.mem
.in_stack_memory
,
1770 p
->v
.mem
.addr
+ bits_to_skip
/ 8,
1771 v_contents
+ offset
/ 8,
1772 this_size_bits
/ 8);
1776 this_size
= bits_to_bytes (bits_to_skip
, this_size_bits
);
1777 buffer
.resize (this_size
);
1782 read_value_memory (v
, offset
,
1783 p
->v
.mem
.in_stack_memory
,
1784 p
->v
.mem
.addr
+ bits_to_skip
/ 8,
1785 buffer
.data (), this_size
);
1786 copy_bitwise (v_contents
, offset
,
1787 buffer
.data (), bits_to_skip
% 8,
1788 this_size_bits
, bits_big_endian
);
1793 if (bits_to_skip
% 8 != 0 || this_size_bits
% 8 != 0)
1797 /* Perform a single read for small sizes. */
1798 read_memory (start_addr
, buffer
.data (),
1803 /* Only the first and last bytes can possibly have
1805 read_memory (start_addr
, buffer
.data (), 1);
1806 read_memory (start_addr
+ this_size
- 1,
1807 &buffer
[this_size
- 1], 1);
1811 copy_bitwise (buffer
.data (), bits_to_skip
% 8,
1812 from_contents
, offset
,
1813 this_size_bits
, bits_big_endian
);
1814 write_memory_with_notification (start_addr
,
1821 case DWARF_VALUE_STACK
:
1825 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1829 struct objfile
*objfile
= c
->per_cu
->objfile ();
1830 struct gdbarch
*objfile_gdbarch
= objfile
->arch ();
1831 ULONGEST stack_value_size_bits
1832 = 8 * TYPE_LENGTH (value_type (p
->v
.value
));
1834 /* Use zeroes if piece reaches beyond stack value. */
1835 if (p
->offset
+ p
->size
> stack_value_size_bits
)
1838 /* Piece is anchored at least significant bit end. */
1839 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
1840 bits_to_skip
+= stack_value_size_bits
- p
->offset
- p
->size
;
1842 bits_to_skip
+= p
->offset
;
1844 copy_bitwise (v_contents
, offset
,
1845 value_contents_all (p
->v
.value
),
1847 this_size_bits
, bits_big_endian
);
1851 case DWARF_VALUE_LITERAL
:
1855 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1859 ULONGEST literal_size_bits
= 8 * p
->v
.literal
.length
;
1860 size_t n
= this_size_bits
;
1862 /* Cut off at the end of the implicit value. */
1863 bits_to_skip
+= p
->offset
;
1864 if (bits_to_skip
>= literal_size_bits
)
1866 if (n
> literal_size_bits
- bits_to_skip
)
1867 n
= literal_size_bits
- bits_to_skip
;
1869 copy_bitwise (v_contents
, offset
,
1870 p
->v
.literal
.data
, bits_to_skip
,
1871 n
, bits_big_endian
);
1875 case DWARF_VALUE_IMPLICIT_POINTER
:
1878 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1882 /* These bits show up as zeros -- but do not cause the value to
1883 be considered optimized-out. */
1886 case DWARF_VALUE_OPTIMIZED_OUT
:
1887 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1891 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
1894 offset
+= this_size_bits
;
1901 read_pieced_value (struct value
*v
)
1903 rw_pieced_value (v
, NULL
);
1907 write_pieced_value (struct value
*to
, struct value
*from
)
1909 rw_pieced_value (to
, from
);
1912 /* An implementation of an lval_funcs method to see whether a value is
1913 a synthetic pointer. */
1916 check_pieced_synthetic_pointer (const struct value
*value
, LONGEST bit_offset
,
1919 struct piece_closure
*c
1920 = (struct piece_closure
*) value_computed_closure (value
);
1923 bit_offset
+= 8 * value_offset (value
);
1924 if (value_bitsize (value
))
1925 bit_offset
+= value_bitpos (value
);
1927 for (i
= 0; i
< c
->pieces
.size () && bit_length
> 0; i
++)
1929 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1930 size_t this_size_bits
= p
->size
;
1934 if (bit_offset
>= this_size_bits
)
1936 bit_offset
-= this_size_bits
;
1940 bit_length
-= this_size_bits
- bit_offset
;
1944 bit_length
-= this_size_bits
;
1946 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
1953 /* A wrapper function for get_frame_address_in_block. */
1956 get_frame_address_in_block_wrapper (void *baton
)
1958 return get_frame_address_in_block ((struct frame_info
*) baton
);
1961 /* Fetch a DW_AT_const_value through a synthetic pointer. */
1963 static struct value
*
1964 fetch_const_value_from_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
1965 struct dwarf2_per_cu_data
*per_cu
,
1968 struct value
*result
= NULL
;
1969 const gdb_byte
*bytes
;
1972 auto_obstack temp_obstack
;
1973 bytes
= dwarf2_fetch_constant_bytes (die
, per_cu
, &temp_obstack
, &len
);
1977 if (byte_offset
>= 0
1978 && byte_offset
+ TYPE_LENGTH (TYPE_TARGET_TYPE (type
)) <= len
)
1980 bytes
+= byte_offset
;
1981 result
= value_from_contents (TYPE_TARGET_TYPE (type
), bytes
);
1984 invalid_synthetic_pointer ();
1987 result
= allocate_optimized_out_value (TYPE_TARGET_TYPE (type
));
1992 /* Fetch the value pointed to by a synthetic pointer. */
1994 static struct value
*
1995 indirect_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
1996 struct dwarf2_per_cu_data
*per_cu
,
1997 struct frame_info
*frame
, struct type
*type
,
1998 bool resolve_abstract_p
)
2000 /* Fetch the location expression of the DIE we're pointing to. */
2001 struct dwarf2_locexpr_baton baton
2002 = dwarf2_fetch_die_loc_sect_off (die
, per_cu
,
2003 get_frame_address_in_block_wrapper
, frame
,
2004 resolve_abstract_p
);
2006 /* Get type of pointed-to DIE. */
2007 struct type
*orig_type
= dwarf2_fetch_die_type_sect_off (die
, per_cu
);
2008 if (orig_type
== NULL
)
2009 invalid_synthetic_pointer ();
2011 /* If pointed-to DIE has a DW_AT_location, evaluate it and return the
2012 resulting value. Otherwise, it may have a DW_AT_const_value instead,
2013 or it may've been optimized out. */
2014 if (baton
.data
!= NULL
)
2015 return dwarf2_evaluate_loc_desc_full (orig_type
, frame
, baton
.data
,
2016 baton
.size
, baton
.per_cu
,
2017 TYPE_TARGET_TYPE (type
),
2020 return fetch_const_value_from_synthetic_pointer (die
, byte_offset
, per_cu
,
2024 /* An implementation of an lval_funcs method to indirect through a
2025 pointer. This handles the synthetic pointer case when needed. */
2027 static struct value
*
2028 indirect_pieced_value (struct value
*value
)
2030 struct piece_closure
*c
2031 = (struct piece_closure
*) value_computed_closure (value
);
2033 struct frame_info
*frame
;
2036 struct dwarf_expr_piece
*piece
= NULL
;
2037 LONGEST byte_offset
;
2038 enum bfd_endian byte_order
;
2040 type
= check_typedef (value_type (value
));
2041 if (type
->code () != TYPE_CODE_PTR
)
2044 bit_length
= 8 * TYPE_LENGTH (type
);
2045 bit_offset
= 8 * value_offset (value
);
2046 if (value_bitsize (value
))
2047 bit_offset
+= value_bitpos (value
);
2049 for (i
= 0; i
< c
->pieces
.size () && bit_length
> 0; i
++)
2051 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2052 size_t this_size_bits
= p
->size
;
2056 if (bit_offset
>= this_size_bits
)
2058 bit_offset
-= this_size_bits
;
2062 bit_length
-= this_size_bits
- bit_offset
;
2066 bit_length
-= this_size_bits
;
2068 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2071 if (bit_length
!= 0)
2072 error (_("Invalid use of DW_OP_implicit_pointer"));
2078 gdb_assert (piece
!= NULL
);
2079 frame
= get_selected_frame (_("No frame selected."));
2081 /* This is an offset requested by GDB, such as value subscripts.
2082 However, due to how synthetic pointers are implemented, this is
2083 always presented to us as a pointer type. This means we have to
2084 sign-extend it manually as appropriate. Use raw
2085 extract_signed_integer directly rather than value_as_address and
2086 sign extend afterwards on architectures that would need it
2087 (mostly everywhere except MIPS, which has signed addresses) as
2088 the later would go through gdbarch_pointer_to_address and thus
2089 return a CORE_ADDR with high bits set on architectures that
2090 encode address spaces and other things in CORE_ADDR. */
2091 byte_order
= gdbarch_byte_order (get_frame_arch (frame
));
2092 byte_offset
= extract_signed_integer (value_contents (value
),
2093 TYPE_LENGTH (type
), byte_order
);
2094 byte_offset
+= piece
->v
.ptr
.offset
;
2096 return indirect_synthetic_pointer (piece
->v
.ptr
.die_sect_off
,
2097 byte_offset
, c
->per_cu
,
2101 /* Implementation of the coerce_ref method of lval_funcs for synthetic C++
2104 static struct value
*
2105 coerce_pieced_ref (const struct value
*value
)
2107 struct type
*type
= check_typedef (value_type (value
));
2109 if (value_bits_synthetic_pointer (value
, value_embedded_offset (value
),
2110 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
2112 const struct piece_closure
*closure
2113 = (struct piece_closure
*) value_computed_closure (value
);
2114 struct frame_info
*frame
2115 = get_selected_frame (_("No frame selected."));
2117 /* gdb represents synthetic pointers as pieced values with a single
2119 gdb_assert (closure
!= NULL
);
2120 gdb_assert (closure
->pieces
.size () == 1);
2122 return indirect_synthetic_pointer
2123 (closure
->pieces
[0].v
.ptr
.die_sect_off
,
2124 closure
->pieces
[0].v
.ptr
.offset
,
2125 closure
->per_cu
, frame
, type
);
2129 /* Else: not a synthetic reference; do nothing. */
2135 copy_pieced_value_closure (const struct value
*v
)
2137 struct piece_closure
*c
2138 = (struct piece_closure
*) value_computed_closure (v
);
2145 free_pieced_value_closure (struct value
*v
)
2147 struct piece_closure
*c
2148 = (struct piece_closure
*) value_computed_closure (v
);
2153 for (dwarf_expr_piece
&p
: c
->pieces
)
2154 if (p
.location
== DWARF_VALUE_STACK
)
2155 value_decref (p
.v
.value
);
2161 /* Functions for accessing a variable described by DW_OP_piece. */
2162 static const struct lval_funcs pieced_value_funcs
= {
2165 indirect_pieced_value
,
2167 check_pieced_synthetic_pointer
,
2168 copy_pieced_value_closure
,
2169 free_pieced_value_closure
2172 /* Evaluate a location description, starting at DATA and with length
2173 SIZE, to find the current location of variable of TYPE in the
2174 context of FRAME. If SUBOBJ_TYPE is non-NULL, return instead the
2175 location of the subobject of type SUBOBJ_TYPE at byte offset
2176 SUBOBJ_BYTE_OFFSET within the variable of type TYPE. */
2178 static struct value
*
2179 dwarf2_evaluate_loc_desc_full (struct type
*type
, struct frame_info
*frame
,
2180 const gdb_byte
*data
, size_t size
,
2181 struct dwarf2_per_cu_data
*per_cu
,
2182 struct type
*subobj_type
,
2183 LONGEST subobj_byte_offset
)
2185 struct value
*retval
;
2186 struct objfile
*objfile
= per_cu
->objfile ();
2188 if (subobj_type
== NULL
)
2191 subobj_byte_offset
= 0;
2193 else if (subobj_byte_offset
< 0)
2194 invalid_synthetic_pointer ();
2197 return allocate_optimized_out_value (subobj_type
);
2199 dwarf2_per_objfile
*per_objfile
= get_dwarf2_per_objfile (objfile
);
2200 dwarf_evaluate_loc_desc
ctx (per_objfile
);
2202 ctx
.per_cu
= per_cu
;
2203 ctx
.obj_address
= 0;
2205 scoped_value_mark free_values
;
2207 ctx
.gdbarch
= objfile
->arch ();
2208 ctx
.addr_size
= per_cu
->addr_size ();
2209 ctx
.ref_addr_size
= per_cu
->ref_addr_size ();
2213 ctx
.eval (data
, size
);
2215 catch (const gdb_exception_error
&ex
)
2217 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2219 free_values
.free_to_mark ();
2220 retval
= allocate_value (subobj_type
);
2221 mark_value_bytes_unavailable (retval
, 0,
2222 TYPE_LENGTH (subobj_type
));
2225 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2227 if (entry_values_debug
)
2228 exception_print (gdb_stdout
, ex
);
2229 free_values
.free_to_mark ();
2230 return allocate_optimized_out_value (subobj_type
);
2236 if (ctx
.pieces
.size () > 0)
2238 struct piece_closure
*c
;
2239 ULONGEST bit_size
= 0;
2241 for (dwarf_expr_piece
&piece
: ctx
.pieces
)
2242 bit_size
+= piece
.size
;
2243 /* Complain if the expression is larger than the size of the
2245 if (bit_size
> 8 * TYPE_LENGTH (type
))
2246 invalid_synthetic_pointer ();
2248 c
= allocate_piece_closure (per_cu
, std::move (ctx
.pieces
), frame
);
2249 /* We must clean up the value chain after creating the piece
2250 closure but before allocating the result. */
2251 free_values
.free_to_mark ();
2252 retval
= allocate_computed_value (subobj_type
,
2253 &pieced_value_funcs
, c
);
2254 set_value_offset (retval
, subobj_byte_offset
);
2258 switch (ctx
.location
)
2260 case DWARF_VALUE_REGISTER
:
2262 struct gdbarch
*arch
= get_frame_arch (frame
);
2264 = longest_to_int (value_as_long (ctx
.fetch (0)));
2265 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, dwarf_regnum
);
2267 if (subobj_byte_offset
!= 0)
2268 error (_("cannot use offset on synthetic pointer to register"));
2269 free_values
.free_to_mark ();
2270 retval
= value_from_register (subobj_type
, gdb_regnum
, frame
);
2271 if (value_optimized_out (retval
))
2275 /* This means the register has undefined value / was
2276 not saved. As we're computing the location of some
2277 variable etc. in the program, not a value for
2278 inspecting a register ($pc, $sp, etc.), return a
2279 generic optimized out value instead, so that we show
2280 <optimized out> instead of <not saved>. */
2281 tmp
= allocate_value (subobj_type
);
2282 value_contents_copy (tmp
, 0, retval
, 0,
2283 TYPE_LENGTH (subobj_type
));
2289 case DWARF_VALUE_MEMORY
:
2291 struct type
*ptr_type
;
2292 CORE_ADDR address
= ctx
.fetch_address (0);
2293 bool in_stack_memory
= ctx
.fetch_in_stack_memory (0);
2295 /* DW_OP_deref_size (and possibly other operations too) may
2296 create a pointer instead of an address. Ideally, the
2297 pointer to address conversion would be performed as part
2298 of those operations, but the type of the object to
2299 which the address refers is not known at the time of
2300 the operation. Therefore, we do the conversion here
2301 since the type is readily available. */
2303 switch (subobj_type
->code ())
2305 case TYPE_CODE_FUNC
:
2306 case TYPE_CODE_METHOD
:
2307 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_func_ptr
;
2310 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_data_ptr
;
2313 address
= value_as_address (value_from_pointer (ptr_type
, address
));
2315 free_values
.free_to_mark ();
2316 retval
= value_at_lazy (subobj_type
,
2317 address
+ subobj_byte_offset
);
2318 if (in_stack_memory
)
2319 set_value_stack (retval
, 1);
2323 case DWARF_VALUE_STACK
:
2325 struct value
*value
= ctx
.fetch (0);
2326 size_t n
= TYPE_LENGTH (value_type (value
));
2327 size_t len
= TYPE_LENGTH (subobj_type
);
2328 size_t max
= TYPE_LENGTH (type
);
2329 struct gdbarch
*objfile_gdbarch
= objfile
->arch ();
2331 if (subobj_byte_offset
+ len
> max
)
2332 invalid_synthetic_pointer ();
2334 /* Preserve VALUE because we are going to free values back
2335 to the mark, but we still need the value contents
2337 value_ref_ptr value_holder
= value_ref_ptr::new_reference (value
);
2338 free_values
.free_to_mark ();
2340 retval
= allocate_value (subobj_type
);
2342 /* The given offset is relative to the actual object. */
2343 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2344 subobj_byte_offset
+= n
- max
;
2346 memcpy (value_contents_raw (retval
),
2347 value_contents_all (value
) + subobj_byte_offset
, len
);
2351 case DWARF_VALUE_LITERAL
:
2354 size_t n
= TYPE_LENGTH (subobj_type
);
2356 if (subobj_byte_offset
+ n
> ctx
.len
)
2357 invalid_synthetic_pointer ();
2359 free_values
.free_to_mark ();
2360 retval
= allocate_value (subobj_type
);
2361 contents
= value_contents_raw (retval
);
2362 memcpy (contents
, ctx
.data
+ subobj_byte_offset
, n
);
2366 case DWARF_VALUE_OPTIMIZED_OUT
:
2367 free_values
.free_to_mark ();
2368 retval
= allocate_optimized_out_value (subobj_type
);
2371 /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
2372 operation by execute_stack_op. */
2373 case DWARF_VALUE_IMPLICIT_POINTER
:
2374 /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
2375 it can only be encountered when making a piece. */
2377 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2381 set_value_initialized (retval
, ctx
.initialized
);
2386 /* The exported interface to dwarf2_evaluate_loc_desc_full; it always
2387 passes 0 as the byte_offset. */
2390 dwarf2_evaluate_loc_desc (struct type
*type
, struct frame_info
*frame
,
2391 const gdb_byte
*data
, size_t size
,
2392 struct dwarf2_per_cu_data
*per_cu
)
2394 return dwarf2_evaluate_loc_desc_full (type
, frame
, data
, size
, per_cu
,
2398 /* A specialization of dwarf_evaluate_loc_desc that is used by
2399 dwarf2_locexpr_baton_eval. This subclass exists to handle the case
2400 where a caller of dwarf2_locexpr_baton_eval passes in some data,
2401 but with the address being 0. In this situation, we arrange for
2402 memory reads to come from the passed-in buffer. */
2404 struct evaluate_for_locexpr_baton
: public dwarf_evaluate_loc_desc
2406 evaluate_for_locexpr_baton (dwarf2_per_objfile
*per_objfile
)
2407 : dwarf_evaluate_loc_desc (per_objfile
)
2410 /* The data that was passed in. */
2411 gdb::array_view
<const gdb_byte
> data_view
;
2413 CORE_ADDR
get_object_address () override
2415 if (data_view
.data () == nullptr && obj_address
== 0)
2416 error (_("Location address is not set."));
2420 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) override
2425 /* Prefer the passed-in memory, if it exists. */
2426 CORE_ADDR offset
= addr
- obj_address
;
2427 if (offset
< data_view
.size () && offset
+ len
<= data_view
.size ())
2429 memcpy (buf
, data_view
.data (), len
);
2433 read_memory (addr
, buf
, len
);
2437 /* Evaluates a dwarf expression and stores the result in VAL,
2438 expecting that the dwarf expression only produces a single
2439 CORE_ADDR. FRAME is the frame in which the expression is
2440 evaluated. ADDR_STACK is a context (location of a variable) and
2441 might be needed to evaluate the location expression.
2442 PUSH_INITIAL_VALUE is true if the address (either from ADDR_STACK,
2443 or the default of 0) should be pushed on the DWARF expression
2444 evaluation stack before evaluating the expression; this is required
2445 by certain forms of DWARF expression. Returns 1 on success, 0
2449 dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton
*dlbaton
,
2450 struct frame_info
*frame
,
2451 const struct property_addr_info
*addr_stack
,
2453 bool push_initial_value
)
2455 if (dlbaton
== NULL
|| dlbaton
->size
== 0)
2458 dwarf2_per_objfile
*per_objfile
= dlbaton
->per_objfile
;
2459 evaluate_for_locexpr_baton
ctx (per_objfile
);
2462 ctx
.per_cu
= dlbaton
->per_cu
;
2463 if (addr_stack
== nullptr)
2464 ctx
.obj_address
= 0;
2467 ctx
.obj_address
= addr_stack
->addr
;
2468 ctx
.data_view
= addr_stack
->valaddr
;
2471 ctx
.gdbarch
= per_objfile
->objfile
->arch ();
2472 ctx
.addr_size
= dlbaton
->per_cu
->addr_size ();
2473 ctx
.ref_addr_size
= dlbaton
->per_cu
->ref_addr_size ();
2475 if (push_initial_value
)
2476 ctx
.push_address (ctx
.obj_address
, false);
2480 ctx
.eval (dlbaton
->data
, dlbaton
->size
);
2482 catch (const gdb_exception_error
&ex
)
2484 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2488 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2490 if (entry_values_debug
)
2491 exception_print (gdb_stdout
, ex
);
2498 switch (ctx
.location
)
2500 case DWARF_VALUE_REGISTER
:
2501 case DWARF_VALUE_MEMORY
:
2502 case DWARF_VALUE_STACK
:
2503 *valp
= ctx
.fetch_address (0);
2504 if (ctx
.location
== DWARF_VALUE_REGISTER
)
2505 *valp
= ctx
.read_addr_from_reg (*valp
);
2507 case DWARF_VALUE_LITERAL
:
2508 *valp
= extract_signed_integer (ctx
.data
, ctx
.len
,
2509 gdbarch_byte_order (ctx
.gdbarch
));
2511 /* Unsupported dwarf values. */
2512 case DWARF_VALUE_OPTIMIZED_OUT
:
2513 case DWARF_VALUE_IMPLICIT_POINTER
:
2520 /* See dwarf2loc.h. */
2523 dwarf2_evaluate_property (const struct dynamic_prop
*prop
,
2524 struct frame_info
*frame
,
2525 const struct property_addr_info
*addr_stack
,
2527 bool push_initial_value
)
2532 if (frame
== NULL
&& has_stack_frames ())
2533 frame
= get_selected_frame (NULL
);
2539 const struct dwarf2_property_baton
*baton
2540 = (const struct dwarf2_property_baton
*) prop
->data
.baton
;
2541 gdb_assert (baton
->property_type
!= NULL
);
2543 if (dwarf2_locexpr_baton_eval (&baton
->locexpr
, frame
, addr_stack
,
2544 value
, push_initial_value
))
2546 if (baton
->locexpr
.is_reference
)
2548 struct value
*val
= value_at (baton
->property_type
, *value
);
2549 *value
= value_as_address (val
);
2553 gdb_assert (baton
->property_type
!= NULL
);
2555 struct type
*type
= check_typedef (baton
->property_type
);
2556 if (TYPE_LENGTH (type
) < sizeof (CORE_ADDR
)
2557 && !TYPE_UNSIGNED (type
))
2559 /* If we have a valid return candidate and it's value
2560 is signed, we have to sign-extend the value because
2561 CORE_ADDR on 64bit machine has 8 bytes but address
2562 size of an 32bit application is bytes. */
2564 = (baton
->locexpr
.per_cu
->addr_size ()
2566 const CORE_ADDR neg_mask
2567 = (~((CORE_ADDR
) 0) << (addr_size
- 1));
2569 /* Check if signed bit is set and sign-extend values. */
2570 if (*value
& neg_mask
)
2581 struct dwarf2_property_baton
*baton
2582 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2584 const gdb_byte
*data
;
2589 || !get_frame_address_in_block_if_available (frame
, &pc
))
2592 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2595 val
= dwarf2_evaluate_loc_desc (baton
->property_type
, frame
, data
,
2596 size
, baton
->loclist
.per_cu
);
2597 if (!value_optimized_out (val
))
2599 *value
= value_as_address (val
);
2607 *value
= prop
->data
.const_val
;
2610 case PROP_ADDR_OFFSET
:
2612 struct dwarf2_property_baton
*baton
2613 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2614 const struct property_addr_info
*pinfo
;
2617 for (pinfo
= addr_stack
; pinfo
!= NULL
; pinfo
= pinfo
->next
)
2619 /* This approach lets us avoid checking the qualifiers. */
2620 if (TYPE_MAIN_TYPE (pinfo
->type
)
2621 == TYPE_MAIN_TYPE (baton
->property_type
))
2625 error (_("cannot find reference address for offset property"));
2626 if (pinfo
->valaddr
.data () != NULL
)
2627 val
= value_from_contents
2628 (baton
->offset_info
.type
,
2629 pinfo
->valaddr
.data () + baton
->offset_info
.offset
);
2631 val
= value_at (baton
->offset_info
.type
,
2632 pinfo
->addr
+ baton
->offset_info
.offset
);
2633 *value
= value_as_address (val
);
2641 /* See dwarf2loc.h. */
2644 dwarf2_compile_property_to_c (string_file
*stream
,
2645 const char *result_name
,
2646 struct gdbarch
*gdbarch
,
2647 unsigned char *registers_used
,
2648 const struct dynamic_prop
*prop
,
2652 struct dwarf2_property_baton
*baton
2653 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2654 const gdb_byte
*data
;
2656 dwarf2_per_cu_data
*per_cu
;
2657 dwarf2_per_objfile
*per_objfile
;
2659 if (prop
->kind
== PROP_LOCEXPR
)
2661 data
= baton
->locexpr
.data
;
2662 size
= baton
->locexpr
.size
;
2663 per_cu
= baton
->locexpr
.per_cu
;
2664 per_objfile
= baton
->locexpr
.per_objfile
;
2668 gdb_assert (prop
->kind
== PROP_LOCLIST
);
2670 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2671 per_cu
= baton
->loclist
.per_cu
;
2672 per_objfile
= baton
->loclist
.per_objfile
;
2675 compile_dwarf_bounds_to_c (stream
, result_name
, prop
, sym
, pc
,
2676 gdbarch
, registers_used
,
2677 per_cu
->addr_size (),
2678 data
, data
+ size
, per_cu
, per_objfile
);
2682 /* Helper functions and baton for dwarf2_loc_desc_get_symbol_read_needs. */
2684 class symbol_needs_eval_context
: public dwarf_expr_context
2687 symbol_needs_eval_context (dwarf2_per_objfile
*per_objfile
)
2688 : dwarf_expr_context (per_objfile
)
2691 enum symbol_needs_kind needs
;
2692 struct dwarf2_per_cu_data
*per_cu
;
2694 /* Reads from registers do require a frame. */
2695 CORE_ADDR
read_addr_from_reg (int regnum
) override
2697 needs
= SYMBOL_NEEDS_FRAME
;
2701 /* "get_reg_value" callback: Reads from registers do require a
2704 struct value
*get_reg_value (struct type
*type
, int regnum
) override
2706 needs
= SYMBOL_NEEDS_FRAME
;
2707 return value_zero (type
, not_lval
);
2710 /* Reads from memory do not require a frame. */
2711 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) override
2713 memset (buf
, 0, len
);
2716 /* Frame-relative accesses do require a frame. */
2717 void get_frame_base (const gdb_byte
**start
, size_t *length
) override
2719 static gdb_byte lit0
= DW_OP_lit0
;
2724 needs
= SYMBOL_NEEDS_FRAME
;
2727 /* CFA accesses require a frame. */
2728 CORE_ADDR
get_frame_cfa () override
2730 needs
= SYMBOL_NEEDS_FRAME
;
2734 CORE_ADDR
get_frame_pc () override
2736 needs
= SYMBOL_NEEDS_FRAME
;
2740 /* Thread-local accesses require registers, but not a frame. */
2741 CORE_ADDR
get_tls_address (CORE_ADDR offset
) override
2743 if (needs
<= SYMBOL_NEEDS_REGISTERS
)
2744 needs
= SYMBOL_NEEDS_REGISTERS
;
2748 /* Helper interface of per_cu_dwarf_call for
2749 dwarf2_loc_desc_get_symbol_read_needs. */
2751 void dwarf_call (cu_offset die_offset
) override
2753 per_cu_dwarf_call (this, die_offset
, per_cu
);
2756 /* Helper interface of sect_variable_value for
2757 dwarf2_loc_desc_get_symbol_read_needs. */
2759 struct value
*dwarf_variable_value (sect_offset sect_off
) override
2761 return sect_variable_value (this, sect_off
, per_cu
);
2764 /* DW_OP_entry_value accesses require a caller, therefore a
2767 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
2768 union call_site_parameter_u kind_u
,
2769 int deref_size
) override
2771 needs
= SYMBOL_NEEDS_FRAME
;
2773 /* The expression may require some stub values on DWARF stack. */
2774 push_address (0, 0);
2777 /* DW_OP_addrx and DW_OP_GNU_addr_index doesn't require a frame. */
2779 CORE_ADDR
get_addr_index (unsigned int index
) override
2781 /* Nothing to do. */
2785 /* DW_OP_push_object_address has a frame already passed through. */
2787 CORE_ADDR
get_object_address () override
2789 /* Nothing to do. */
2794 /* Compute the correct symbol_needs_kind value for the location
2795 expression at DATA (length SIZE). */
2797 static enum symbol_needs_kind
2798 dwarf2_loc_desc_get_symbol_read_needs (const gdb_byte
*data
, size_t size
,
2799 struct dwarf2_per_cu_data
*per_cu
)
2802 struct objfile
*objfile
= per_cu
->objfile ();
2804 scoped_value_mark free_values
;
2806 symbol_needs_eval_context
ctx (get_dwarf2_per_objfile (objfile
));
2808 ctx
.needs
= SYMBOL_NEEDS_NONE
;
2809 ctx
.per_cu
= per_cu
;
2810 ctx
.gdbarch
= objfile
->arch ();
2811 ctx
.addr_size
= per_cu
->addr_size ();
2812 ctx
.ref_addr_size
= per_cu
->ref_addr_size ();
2814 ctx
.eval (data
, size
);
2816 in_reg
= ctx
.location
== DWARF_VALUE_REGISTER
;
2818 /* If the location has several pieces, and any of them are in
2819 registers, then we will need a frame to fetch them from. */
2820 for (dwarf_expr_piece
&p
: ctx
.pieces
)
2821 if (p
.location
== DWARF_VALUE_REGISTER
)
2825 ctx
.needs
= SYMBOL_NEEDS_FRAME
;
2829 /* A helper function that throws an unimplemented error mentioning a
2830 given DWARF operator. */
2832 static void ATTRIBUTE_NORETURN
2833 unimplemented (unsigned int op
)
2835 const char *name
= get_DW_OP_name (op
);
2838 error (_("DWARF operator %s cannot be translated to an agent expression"),
2841 error (_("Unknown DWARF operator 0x%02x cannot be translated "
2842 "to an agent expression"),
2848 This is basically a wrapper on gdbarch_dwarf2_reg_to_regnum so that we
2849 can issue a complaint, which is better than having every target's
2850 implementation of dwarf2_reg_to_regnum do it. */
2853 dwarf_reg_to_regnum (struct gdbarch
*arch
, int dwarf_reg
)
2855 int reg
= gdbarch_dwarf2_reg_to_regnum (arch
, dwarf_reg
);
2859 complaint (_("bad DWARF register number %d"), dwarf_reg
);
2864 /* Subroutine of dwarf_reg_to_regnum_or_error to simplify it.
2865 Throw an error because DWARF_REG is bad. */
2868 throw_bad_regnum_error (ULONGEST dwarf_reg
)
2870 /* Still want to print -1 as "-1".
2871 We *could* have int and ULONGEST versions of dwarf2_reg_to_regnum_or_error
2872 but that's overkill for now. */
2873 if ((int) dwarf_reg
== dwarf_reg
)
2874 error (_("Unable to access DWARF register number %d"), (int) dwarf_reg
);
2875 error (_("Unable to access DWARF register number %s"),
2876 pulongest (dwarf_reg
));
2879 /* See dwarf2loc.h. */
2882 dwarf_reg_to_regnum_or_error (struct gdbarch
*arch
, ULONGEST dwarf_reg
)
2886 if (dwarf_reg
> INT_MAX
)
2887 throw_bad_regnum_error (dwarf_reg
);
2888 /* Yes, we will end up issuing a complaint and an error if DWARF_REG is
2889 bad, but that's ok. */
2890 reg
= dwarf_reg_to_regnum (arch
, (int) dwarf_reg
);
2892 throw_bad_regnum_error (dwarf_reg
);
2896 /* A helper function that emits an access to memory. ARCH is the
2897 target architecture. EXPR is the expression which we are building.
2898 NBITS is the number of bits we want to read. This emits the
2899 opcodes needed to read the memory and then extract the desired
2903 access_memory (struct gdbarch
*arch
, struct agent_expr
*expr
, ULONGEST nbits
)
2905 ULONGEST nbytes
= (nbits
+ 7) / 8;
2907 gdb_assert (nbytes
> 0 && nbytes
<= sizeof (LONGEST
));
2910 ax_trace_quick (expr
, nbytes
);
2913 ax_simple (expr
, aop_ref8
);
2914 else if (nbits
<= 16)
2915 ax_simple (expr
, aop_ref16
);
2916 else if (nbits
<= 32)
2917 ax_simple (expr
, aop_ref32
);
2919 ax_simple (expr
, aop_ref64
);
2921 /* If we read exactly the number of bytes we wanted, we're done. */
2922 if (8 * nbytes
== nbits
)
2925 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
)
2927 /* On a bits-big-endian machine, we want the high-order
2929 ax_const_l (expr
, 8 * nbytes
- nbits
);
2930 ax_simple (expr
, aop_rsh_unsigned
);
2934 /* On a bits-little-endian box, we want the low-order NBITS. */
2935 ax_zero_ext (expr
, nbits
);
2939 /* A helper function to return the frame's PC. */
2942 get_ax_pc (void *baton
)
2944 struct agent_expr
*expr
= (struct agent_expr
*) baton
;
2949 /* Compile a DWARF location expression to an agent expression.
2951 EXPR is the agent expression we are building.
2952 LOC is the agent value we modify.
2953 ARCH is the architecture.
2954 ADDR_SIZE is the size of addresses, in bytes.
2955 OP_PTR is the start of the location expression.
2956 OP_END is one past the last byte of the location expression.
2958 This will throw an exception for various kinds of errors -- for
2959 example, if the expression cannot be compiled, or if the expression
2963 dwarf2_compile_expr_to_ax (struct agent_expr
*expr
, struct axs_value
*loc
,
2964 unsigned int addr_size
, const gdb_byte
*op_ptr
,
2965 const gdb_byte
*op_end
,
2966 dwarf2_per_cu_data
*per_cu
,
2967 dwarf2_per_objfile
*per_objfile
)
2969 gdbarch
*arch
= expr
->gdbarch
;
2970 std::vector
<int> dw_labels
, patches
;
2971 const gdb_byte
* const base
= op_ptr
;
2972 const gdb_byte
*previous_piece
= op_ptr
;
2973 enum bfd_endian byte_order
= gdbarch_byte_order (arch
);
2974 ULONGEST bits_collected
= 0;
2975 unsigned int addr_size_bits
= 8 * addr_size
;
2976 bool bits_big_endian
= byte_order
== BFD_ENDIAN_BIG
;
2978 std::vector
<int> offsets (op_end
- op_ptr
, -1);
2980 /* By default we are making an address. */
2981 loc
->kind
= axs_lvalue_memory
;
2983 while (op_ptr
< op_end
)
2985 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *op_ptr
;
2986 uint64_t uoffset
, reg
;
2990 offsets
[op_ptr
- base
] = expr
->len
;
2993 /* Our basic approach to code generation is to map DWARF
2994 operations directly to AX operations. However, there are
2997 First, DWARF works on address-sized units, but AX always uses
2998 LONGEST. For most operations we simply ignore this
2999 difference; instead we generate sign extensions as needed
3000 before division and comparison operations. It would be nice
3001 to omit the sign extensions, but there is no way to determine
3002 the size of the target's LONGEST. (This code uses the size
3003 of the host LONGEST in some cases -- that is a bug but it is
3006 Second, some DWARF operations cannot be translated to AX.
3007 For these we simply fail. See
3008 http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
3043 ax_const_l (expr
, op
- DW_OP_lit0
);
3047 uoffset
= extract_unsigned_integer (op_ptr
, addr_size
, byte_order
);
3048 op_ptr
+= addr_size
;
3049 /* Some versions of GCC emit DW_OP_addr before
3050 DW_OP_GNU_push_tls_address. In this case the value is an
3051 index, not an address. We don't support things like
3052 branching between the address and the TLS op. */
3053 if (op_ptr
>= op_end
|| *op_ptr
!= DW_OP_GNU_push_tls_address
)
3054 uoffset
+= per_objfile
->objfile
->text_section_offset ();
3055 ax_const_l (expr
, uoffset
);
3059 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 1, byte_order
));
3063 ax_const_l (expr
, extract_signed_integer (op_ptr
, 1, byte_order
));
3067 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 2, byte_order
));
3071 ax_const_l (expr
, extract_signed_integer (op_ptr
, 2, byte_order
));
3075 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 4, byte_order
));
3079 ax_const_l (expr
, extract_signed_integer (op_ptr
, 4, byte_order
));
3083 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 8, byte_order
));
3087 ax_const_l (expr
, extract_signed_integer (op_ptr
, 8, byte_order
));
3091 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3092 ax_const_l (expr
, uoffset
);
3095 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3096 ax_const_l (expr
, offset
);
3131 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3132 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_reg0
);
3133 loc
->kind
= axs_lvalue_register
;
3137 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3138 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3139 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3140 loc
->kind
= axs_lvalue_register
;
3143 case DW_OP_implicit_value
:
3147 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &len
);
3148 if (op_ptr
+ len
> op_end
)
3149 error (_("DW_OP_implicit_value: too few bytes available."));
3150 if (len
> sizeof (ULONGEST
))
3151 error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
3154 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, len
,
3157 dwarf_expr_require_composition (op_ptr
, op_end
,
3158 "DW_OP_implicit_value");
3160 loc
->kind
= axs_rvalue
;
3164 case DW_OP_stack_value
:
3165 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_stack_value");
3166 loc
->kind
= axs_rvalue
;
3201 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3202 i
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_breg0
);
3206 ax_const_l (expr
, offset
);
3207 ax_simple (expr
, aop_add
);
3212 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3213 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3214 i
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3218 ax_const_l (expr
, offset
);
3219 ax_simple (expr
, aop_add
);
3225 const gdb_byte
*datastart
;
3227 const struct block
*b
;
3228 struct symbol
*framefunc
;
3230 b
= block_for_pc (expr
->scope
);
3233 error (_("No block found for address"));
3235 framefunc
= block_linkage_function (b
);
3238 error (_("No function found for block"));
3240 func_get_frame_base_dwarf_block (framefunc
, expr
->scope
,
3241 &datastart
, &datalen
);
3243 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3244 dwarf2_compile_expr_to_ax (expr
, loc
, addr_size
, datastart
,
3245 datastart
+ datalen
, per_cu
,
3247 if (loc
->kind
== axs_lvalue_register
)
3248 require_rvalue (expr
, loc
);
3252 ax_const_l (expr
, offset
);
3253 ax_simple (expr
, aop_add
);
3256 loc
->kind
= axs_lvalue_memory
;
3261 ax_simple (expr
, aop_dup
);
3265 ax_simple (expr
, aop_pop
);
3270 ax_pick (expr
, offset
);
3274 ax_simple (expr
, aop_swap
);
3282 ax_simple (expr
, aop_rot
);
3286 case DW_OP_deref_size
:
3290 if (op
== DW_OP_deref_size
)
3295 if (size
!= 1 && size
!= 2 && size
!= 4 && size
!= 8)
3296 error (_("Unsupported size %d in %s"),
3297 size
, get_DW_OP_name (op
));
3298 access_memory (arch
, expr
, size
* TARGET_CHAR_BIT
);
3303 /* Sign extend the operand. */
3304 ax_ext (expr
, addr_size_bits
);
3305 ax_simple (expr
, aop_dup
);
3306 ax_const_l (expr
, 0);
3307 ax_simple (expr
, aop_less_signed
);
3308 ax_simple (expr
, aop_log_not
);
3309 i
= ax_goto (expr
, aop_if_goto
);
3310 /* We have to emit 0 - X. */
3311 ax_const_l (expr
, 0);
3312 ax_simple (expr
, aop_swap
);
3313 ax_simple (expr
, aop_sub
);
3314 ax_label (expr
, i
, expr
->len
);
3318 /* No need to sign extend here. */
3319 ax_const_l (expr
, 0);
3320 ax_simple (expr
, aop_swap
);
3321 ax_simple (expr
, aop_sub
);
3325 /* Sign extend the operand. */
3326 ax_ext (expr
, addr_size_bits
);
3327 ax_simple (expr
, aop_bit_not
);
3330 case DW_OP_plus_uconst
:
3331 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3332 /* It would be really weird to emit `DW_OP_plus_uconst 0',
3333 but we micro-optimize anyhow. */
3336 ax_const_l (expr
, reg
);
3337 ax_simple (expr
, aop_add
);
3342 ax_simple (expr
, aop_bit_and
);
3346 /* Sign extend the operands. */
3347 ax_ext (expr
, addr_size_bits
);
3348 ax_simple (expr
, aop_swap
);
3349 ax_ext (expr
, addr_size_bits
);
3350 ax_simple (expr
, aop_swap
);
3351 ax_simple (expr
, aop_div_signed
);
3355 ax_simple (expr
, aop_sub
);
3359 ax_simple (expr
, aop_rem_unsigned
);
3363 ax_simple (expr
, aop_mul
);
3367 ax_simple (expr
, aop_bit_or
);
3371 ax_simple (expr
, aop_add
);
3375 ax_simple (expr
, aop_lsh
);
3379 ax_simple (expr
, aop_rsh_unsigned
);
3383 ax_simple (expr
, aop_rsh_signed
);
3387 ax_simple (expr
, aop_bit_xor
);
3391 /* Sign extend the operands. */
3392 ax_ext (expr
, addr_size_bits
);
3393 ax_simple (expr
, aop_swap
);
3394 ax_ext (expr
, addr_size_bits
);
3395 /* Note no swap here: A <= B is !(B < A). */
3396 ax_simple (expr
, aop_less_signed
);
3397 ax_simple (expr
, aop_log_not
);
3401 /* Sign extend the operands. */
3402 ax_ext (expr
, addr_size_bits
);
3403 ax_simple (expr
, aop_swap
);
3404 ax_ext (expr
, addr_size_bits
);
3405 ax_simple (expr
, aop_swap
);
3406 /* A >= B is !(A < B). */
3407 ax_simple (expr
, aop_less_signed
);
3408 ax_simple (expr
, aop_log_not
);
3412 /* Sign extend the operands. */
3413 ax_ext (expr
, addr_size_bits
);
3414 ax_simple (expr
, aop_swap
);
3415 ax_ext (expr
, addr_size_bits
);
3416 /* No need for a second swap here. */
3417 ax_simple (expr
, aop_equal
);
3421 /* Sign extend the operands. */
3422 ax_ext (expr
, addr_size_bits
);
3423 ax_simple (expr
, aop_swap
);
3424 ax_ext (expr
, addr_size_bits
);
3425 ax_simple (expr
, aop_swap
);
3426 ax_simple (expr
, aop_less_signed
);
3430 /* Sign extend the operands. */
3431 ax_ext (expr
, addr_size_bits
);
3432 ax_simple (expr
, aop_swap
);
3433 ax_ext (expr
, addr_size_bits
);
3434 /* Note no swap here: A > B is B < A. */
3435 ax_simple (expr
, aop_less_signed
);
3439 /* Sign extend the operands. */
3440 ax_ext (expr
, addr_size_bits
);
3441 ax_simple (expr
, aop_swap
);
3442 ax_ext (expr
, addr_size_bits
);
3443 /* No need for a swap here. */
3444 ax_simple (expr
, aop_equal
);
3445 ax_simple (expr
, aop_log_not
);
3448 case DW_OP_call_frame_cfa
:
3451 CORE_ADDR text_offset
;
3453 const gdb_byte
*cfa_start
, *cfa_end
;
3455 if (dwarf2_fetch_cfa_info (arch
, expr
->scope
, per_cu
,
3457 &text_offset
, &cfa_start
, &cfa_end
))
3460 ax_reg (expr
, regnum
);
3463 ax_const_l (expr
, off
);
3464 ax_simple (expr
, aop_add
);
3469 /* Another expression. */
3470 ax_const_l (expr
, text_offset
);
3471 dwarf2_compile_expr_to_ax (expr
, loc
, addr_size
, cfa_start
,
3472 cfa_end
, per_cu
, per_objfile
);
3475 loc
->kind
= axs_lvalue_memory
;
3479 case DW_OP_GNU_push_tls_address
:
3480 case DW_OP_form_tls_address
:
3484 case DW_OP_push_object_address
:
3489 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3491 i
= ax_goto (expr
, aop_goto
);
3492 dw_labels
.push_back (op_ptr
+ offset
- base
);
3493 patches
.push_back (i
);
3497 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3499 /* Zero extend the operand. */
3500 ax_zero_ext (expr
, addr_size_bits
);
3501 i
= ax_goto (expr
, aop_if_goto
);
3502 dw_labels
.push_back (op_ptr
+ offset
- base
);
3503 patches
.push_back (i
);
3510 case DW_OP_bit_piece
:
3514 if (op_ptr
- 1 == previous_piece
)
3515 error (_("Cannot translate empty pieces to agent expressions"));
3516 previous_piece
= op_ptr
- 1;
3518 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &size
);
3519 if (op
== DW_OP_piece
)
3525 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3527 if (bits_collected
+ size
> 8 * sizeof (LONGEST
))
3528 error (_("Expression pieces exceed word size"));
3530 /* Access the bits. */
3533 case axs_lvalue_register
:
3534 ax_reg (expr
, loc
->u
.reg
);
3537 case axs_lvalue_memory
:
3538 /* Offset the pointer, if needed. */
3541 ax_const_l (expr
, uoffset
/ 8);
3542 ax_simple (expr
, aop_add
);
3545 access_memory (arch
, expr
, size
);
3549 /* For a bits-big-endian target, shift up what we already
3550 have. For a bits-little-endian target, shift up the
3551 new data. Note that there is a potential bug here if
3552 the DWARF expression leaves multiple values on the
3554 if (bits_collected
> 0)
3556 if (bits_big_endian
)
3558 ax_simple (expr
, aop_swap
);
3559 ax_const_l (expr
, size
);
3560 ax_simple (expr
, aop_lsh
);
3561 /* We don't need a second swap here, because
3562 aop_bit_or is symmetric. */
3566 ax_const_l (expr
, size
);
3567 ax_simple (expr
, aop_lsh
);
3569 ax_simple (expr
, aop_bit_or
);
3572 bits_collected
+= size
;
3573 loc
->kind
= axs_rvalue
;
3577 case DW_OP_GNU_uninit
:
3583 struct dwarf2_locexpr_baton block
;
3584 int size
= (op
== DW_OP_call2
? 2 : 4);
3586 uoffset
= extract_unsigned_integer (op_ptr
, size
, byte_order
);
3589 cu_offset cuoffset
= (cu_offset
) uoffset
;
3590 block
= dwarf2_fetch_die_loc_cu_off (cuoffset
, per_cu
,
3593 /* DW_OP_call_ref is currently not supported. */
3594 gdb_assert (block
.per_cu
== per_cu
);
3596 dwarf2_compile_expr_to_ax (expr
, loc
, addr_size
, block
.data
,
3597 block
.data
+ block
.size
, per_cu
,
3602 case DW_OP_call_ref
:
3605 case DW_OP_GNU_variable_value
:
3613 /* Patch all the branches we emitted. */
3614 for (int i
= 0; i
< patches
.size (); ++i
)
3616 int targ
= offsets
[dw_labels
[i
]];
3618 internal_error (__FILE__
, __LINE__
, _("invalid label"));
3619 ax_label (expr
, patches
[i
], targ
);
3624 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
3625 evaluator to calculate the location. */
3626 static struct value
*
3627 locexpr_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
3629 struct dwarf2_locexpr_baton
*dlbaton
3630 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3633 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3634 dlbaton
->size
, dlbaton
->per_cu
);
3639 /* Return the value of SYMBOL in FRAME at (callee) FRAME's function
3640 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
3643 static struct value
*
3644 locexpr_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
3646 struct dwarf2_locexpr_baton
*dlbaton
3647 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3649 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3653 /* Implementation of get_symbol_read_needs from
3654 symbol_computed_ops. */
3656 static enum symbol_needs_kind
3657 locexpr_get_symbol_read_needs (struct symbol
*symbol
)
3659 struct dwarf2_locexpr_baton
*dlbaton
3660 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3662 return dwarf2_loc_desc_get_symbol_read_needs (dlbaton
->data
, dlbaton
->size
,
3666 /* Return true if DATA points to the end of a piece. END is one past
3667 the last byte in the expression. */
3670 piece_end_p (const gdb_byte
*data
, const gdb_byte
*end
)
3672 return data
== end
|| data
[0] == DW_OP_piece
|| data
[0] == DW_OP_bit_piece
;
3675 /* Helper for locexpr_describe_location_piece that finds the name of a
3679 locexpr_regname (struct gdbarch
*gdbarch
, int dwarf_regnum
)
3683 /* This doesn't use dwarf_reg_to_regnum_or_error on purpose.
3684 We'd rather print *something* here than throw an error. */
3685 regnum
= dwarf_reg_to_regnum (gdbarch
, dwarf_regnum
);
3686 /* gdbarch_register_name may just return "", return something more
3687 descriptive for bad register numbers. */
3690 /* The text is output as "$bad_register_number".
3691 That is why we use the underscores. */
3692 return _("bad_register_number");
3694 return gdbarch_register_name (gdbarch
, regnum
);
3697 /* Nicely describe a single piece of a location, returning an updated
3698 position in the bytecode sequence. This function cannot recognize
3699 all locations; if a location is not recognized, it simply returns
3700 DATA. If there is an error during reading, e.g. we run off the end
3701 of the buffer, an error is thrown. */
3703 static const gdb_byte
*
3704 locexpr_describe_location_piece (struct symbol
*symbol
, struct ui_file
*stream
,
3705 CORE_ADDR addr
, dwarf2_per_cu_data
*per_cu
,
3706 dwarf2_per_objfile
*per_objfile
,
3707 const gdb_byte
*data
, const gdb_byte
*end
,
3708 unsigned int addr_size
)
3710 objfile
*objfile
= per_objfile
->objfile
;
3711 struct gdbarch
*gdbarch
= objfile
->arch ();
3714 if (data
[0] >= DW_OP_reg0
&& data
[0] <= DW_OP_reg31
)
3716 fprintf_filtered (stream
, _("a variable in $%s"),
3717 locexpr_regname (gdbarch
, data
[0] - DW_OP_reg0
));
3720 else if (data
[0] == DW_OP_regx
)
3724 data
= safe_read_uleb128 (data
+ 1, end
, ®
);
3725 fprintf_filtered (stream
, _("a variable in $%s"),
3726 locexpr_regname (gdbarch
, reg
));
3728 else if (data
[0] == DW_OP_fbreg
)
3730 const struct block
*b
;
3731 struct symbol
*framefunc
;
3733 int64_t frame_offset
;
3734 const gdb_byte
*base_data
, *new_data
, *save_data
= data
;
3736 int64_t base_offset
= 0;
3738 new_data
= safe_read_sleb128 (data
+ 1, end
, &frame_offset
);
3739 if (!piece_end_p (new_data
, end
))
3743 b
= block_for_pc (addr
);
3746 error (_("No block found for address for symbol \"%s\"."),
3747 symbol
->print_name ());
3749 framefunc
= block_linkage_function (b
);
3752 error (_("No function found for block for symbol \"%s\"."),
3753 symbol
->print_name ());
3755 func_get_frame_base_dwarf_block (framefunc
, addr
, &base_data
, &base_size
);
3757 if (base_data
[0] >= DW_OP_breg0
&& base_data
[0] <= DW_OP_breg31
)
3759 const gdb_byte
*buf_end
;
3761 frame_reg
= base_data
[0] - DW_OP_breg0
;
3762 buf_end
= safe_read_sleb128 (base_data
+ 1, base_data
+ base_size
,
3764 if (buf_end
!= base_data
+ base_size
)
3765 error (_("Unexpected opcode after "
3766 "DW_OP_breg%u for symbol \"%s\"."),
3767 frame_reg
, symbol
->print_name ());
3769 else if (base_data
[0] >= DW_OP_reg0
&& base_data
[0] <= DW_OP_reg31
)
3771 /* The frame base is just the register, with no offset. */
3772 frame_reg
= base_data
[0] - DW_OP_reg0
;
3777 /* We don't know what to do with the frame base expression,
3778 so we can't trace this variable; give up. */
3782 fprintf_filtered (stream
,
3783 _("a variable at frame base reg $%s offset %s+%s"),
3784 locexpr_regname (gdbarch
, frame_reg
),
3785 plongest (base_offset
), plongest (frame_offset
));
3787 else if (data
[0] >= DW_OP_breg0
&& data
[0] <= DW_OP_breg31
3788 && piece_end_p (data
, end
))
3792 data
= safe_read_sleb128 (data
+ 1, end
, &offset
);
3794 fprintf_filtered (stream
,
3795 _("a variable at offset %s from base reg $%s"),
3797 locexpr_regname (gdbarch
, data
[0] - DW_OP_breg0
));
3800 /* The location expression for a TLS variable looks like this (on a
3803 DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
3804 (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
3806 0x3 is the encoding for DW_OP_addr, which has an operand as long
3807 as the size of an address on the target machine (here is 8
3808 bytes). Note that more recent version of GCC emit DW_OP_const4u
3809 or DW_OP_const8u, depending on address size, rather than
3810 DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address.
3811 The operand represents the offset at which the variable is within
3812 the thread local storage. */
3814 else if (data
+ 1 + addr_size
< end
3815 && (data
[0] == DW_OP_addr
3816 || (addr_size
== 4 && data
[0] == DW_OP_const4u
)
3817 || (addr_size
== 8 && data
[0] == DW_OP_const8u
))
3818 && (data
[1 + addr_size
] == DW_OP_GNU_push_tls_address
3819 || data
[1 + addr_size
] == DW_OP_form_tls_address
)
3820 && piece_end_p (data
+ 2 + addr_size
, end
))
3823 offset
= extract_unsigned_integer (data
+ 1, addr_size
,
3824 gdbarch_byte_order (gdbarch
));
3826 fprintf_filtered (stream
,
3827 _("a thread-local variable at offset 0x%s "
3828 "in the thread-local storage for `%s'"),
3829 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3831 data
+= 1 + addr_size
+ 1;
3834 /* With -gsplit-dwarf a TLS variable can also look like this:
3835 DW_AT_location : 3 byte block: fc 4 e0
3836 (DW_OP_GNU_const_index: 4;
3837 DW_OP_GNU_push_tls_address) */
3838 else if (data
+ 3 <= end
3839 && data
+ 1 + (leb128_size
= skip_leb128 (data
+ 1, end
)) < end
3840 && data
[0] == DW_OP_GNU_const_index
3842 && (data
[1 + leb128_size
] == DW_OP_GNU_push_tls_address
3843 || data
[1 + leb128_size
] == DW_OP_form_tls_address
)
3844 && piece_end_p (data
+ 2 + leb128_size
, end
))
3848 data
= safe_read_uleb128 (data
+ 1, end
, &offset
);
3849 offset
= dwarf2_read_addr_index (per_cu
, per_objfile
, offset
);
3850 fprintf_filtered (stream
,
3851 _("a thread-local variable at offset 0x%s "
3852 "in the thread-local storage for `%s'"),
3853 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3857 else if (data
[0] >= DW_OP_lit0
3858 && data
[0] <= DW_OP_lit31
3860 && data
[1] == DW_OP_stack_value
)
3862 fprintf_filtered (stream
, _("the constant %d"), data
[0] - DW_OP_lit0
);
3869 /* Disassemble an expression, stopping at the end of a piece or at the
3870 end of the expression. Returns a pointer to the next unread byte
3871 in the input expression. If ALL is nonzero, then this function
3872 will keep going until it reaches the end of the expression.
3873 If there is an error during reading, e.g. we run off the end
3874 of the buffer, an error is thrown. */
3876 static const gdb_byte
*
3877 disassemble_dwarf_expression (struct ui_file
*stream
,
3878 struct gdbarch
*arch
, unsigned int addr_size
,
3879 int offset_size
, const gdb_byte
*start
,
3880 const gdb_byte
*data
, const gdb_byte
*end
,
3881 int indent
, int all
,
3882 dwarf2_per_cu_data
*per_cu
,
3883 dwarf2_per_objfile
*per_objfile
)
3887 || (data
[0] != DW_OP_piece
&& data
[0] != DW_OP_bit_piece
)))
3889 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *data
++;
3894 name
= get_DW_OP_name (op
);
3897 error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
3898 op
, (long) (data
- 1 - start
));
3899 fprintf_filtered (stream
, " %*ld: %s", indent
+ 4,
3900 (long) (data
- 1 - start
), name
);
3905 ul
= extract_unsigned_integer (data
, addr_size
,
3906 gdbarch_byte_order (arch
));
3908 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
3912 ul
= extract_unsigned_integer (data
, 1, gdbarch_byte_order (arch
));
3914 fprintf_filtered (stream
, " %s", pulongest (ul
));
3917 l
= extract_signed_integer (data
, 1, gdbarch_byte_order (arch
));
3919 fprintf_filtered (stream
, " %s", plongest (l
));
3922 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
3924 fprintf_filtered (stream
, " %s", pulongest (ul
));
3927 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
3929 fprintf_filtered (stream
, " %s", plongest (l
));
3932 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
3934 fprintf_filtered (stream
, " %s", pulongest (ul
));
3937 l
= extract_signed_integer (data
, 4, gdbarch_byte_order (arch
));
3939 fprintf_filtered (stream
, " %s", plongest (l
));
3942 ul
= extract_unsigned_integer (data
, 8, gdbarch_byte_order (arch
));
3944 fprintf_filtered (stream
, " %s", pulongest (ul
));
3947 l
= extract_signed_integer (data
, 8, gdbarch_byte_order (arch
));
3949 fprintf_filtered (stream
, " %s", plongest (l
));
3952 data
= safe_read_uleb128 (data
, end
, &ul
);
3953 fprintf_filtered (stream
, " %s", pulongest (ul
));
3956 data
= safe_read_sleb128 (data
, end
, &l
);
3957 fprintf_filtered (stream
, " %s", plongest (l
));
3992 fprintf_filtered (stream
, " [$%s]",
3993 locexpr_regname (arch
, op
- DW_OP_reg0
));
3997 data
= safe_read_uleb128 (data
, end
, &ul
);
3998 fprintf_filtered (stream
, " %s [$%s]", pulongest (ul
),
3999 locexpr_regname (arch
, (int) ul
));
4002 case DW_OP_implicit_value
:
4003 data
= safe_read_uleb128 (data
, end
, &ul
);
4005 fprintf_filtered (stream
, " %s", pulongest (ul
));
4040 data
= safe_read_sleb128 (data
, end
, &l
);
4041 fprintf_filtered (stream
, " %s [$%s]", plongest (l
),
4042 locexpr_regname (arch
, op
- DW_OP_breg0
));
4046 data
= safe_read_uleb128 (data
, end
, &ul
);
4047 data
= safe_read_sleb128 (data
, end
, &l
);
4048 fprintf_filtered (stream
, " register %s [$%s] offset %s",
4050 locexpr_regname (arch
, (int) ul
),
4055 data
= safe_read_sleb128 (data
, end
, &l
);
4056 fprintf_filtered (stream
, " %s", plongest (l
));
4059 case DW_OP_xderef_size
:
4060 case DW_OP_deref_size
:
4062 fprintf_filtered (stream
, " %d", *data
);
4066 case DW_OP_plus_uconst
:
4067 data
= safe_read_uleb128 (data
, end
, &ul
);
4068 fprintf_filtered (stream
, " %s", pulongest (ul
));
4072 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4074 fprintf_filtered (stream
, " to %ld",
4075 (long) (data
+ l
- start
));
4079 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4081 fprintf_filtered (stream
, " %ld",
4082 (long) (data
+ l
- start
));
4086 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4088 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 2));
4092 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4094 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4097 case DW_OP_call_ref
:
4098 ul
= extract_unsigned_integer (data
, offset_size
,
4099 gdbarch_byte_order (arch
));
4100 data
+= offset_size
;
4101 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4105 data
= safe_read_uleb128 (data
, end
, &ul
);
4106 fprintf_filtered (stream
, " %s (bytes)", pulongest (ul
));
4109 case DW_OP_bit_piece
:
4113 data
= safe_read_uleb128 (data
, end
, &ul
);
4114 data
= safe_read_uleb128 (data
, end
, &offset
);
4115 fprintf_filtered (stream
, " size %s offset %s (bits)",
4116 pulongest (ul
), pulongest (offset
));
4120 case DW_OP_implicit_pointer
:
4121 case DW_OP_GNU_implicit_pointer
:
4123 ul
= extract_unsigned_integer (data
, offset_size
,
4124 gdbarch_byte_order (arch
));
4125 data
+= offset_size
;
4127 data
= safe_read_sleb128 (data
, end
, &l
);
4129 fprintf_filtered (stream
, " DIE %s offset %s",
4130 phex_nz (ul
, offset_size
),
4135 case DW_OP_deref_type
:
4136 case DW_OP_GNU_deref_type
:
4138 int deref_addr_size
= *data
++;
4141 data
= safe_read_uleb128 (data
, end
, &ul
);
4142 cu_offset offset
= (cu_offset
) ul
;
4143 type
= dwarf2_get_die_type (offset
, per_cu
);
4144 fprintf_filtered (stream
, "<");
4145 type_print (type
, "", stream
, -1);
4146 fprintf_filtered (stream
, " [0x%s]> %d",
4147 phex_nz (to_underlying (offset
), 0),
4152 case DW_OP_const_type
:
4153 case DW_OP_GNU_const_type
:
4157 data
= safe_read_uleb128 (data
, end
, &ul
);
4158 cu_offset type_die
= (cu_offset
) ul
;
4159 type
= dwarf2_get_die_type (type_die
, per_cu
);
4160 fprintf_filtered (stream
, "<");
4161 type_print (type
, "", stream
, -1);
4162 fprintf_filtered (stream
, " [0x%s]>",
4163 phex_nz (to_underlying (type_die
), 0));
4166 fprintf_filtered (stream
, " %d byte block:", n
);
4167 for (int i
= 0; i
< n
; ++i
)
4168 fprintf_filtered (stream
, " %02x", data
[i
]);
4173 case DW_OP_regval_type
:
4174 case DW_OP_GNU_regval_type
:
4179 data
= safe_read_uleb128 (data
, end
, ®
);
4180 data
= safe_read_uleb128 (data
, end
, &ul
);
4181 cu_offset type_die
= (cu_offset
) ul
;
4183 type
= dwarf2_get_die_type (type_die
, per_cu
);
4184 fprintf_filtered (stream
, "<");
4185 type_print (type
, "", stream
, -1);
4186 fprintf_filtered (stream
, " [0x%s]> [$%s]",
4187 phex_nz (to_underlying (type_die
), 0),
4188 locexpr_regname (arch
, reg
));
4193 case DW_OP_GNU_convert
:
4194 case DW_OP_reinterpret
:
4195 case DW_OP_GNU_reinterpret
:
4197 data
= safe_read_uleb128 (data
, end
, &ul
);
4198 cu_offset type_die
= (cu_offset
) ul
;
4200 if (to_underlying (type_die
) == 0)
4201 fprintf_filtered (stream
, "<0>");
4206 type
= dwarf2_get_die_type (type_die
, per_cu
);
4207 fprintf_filtered (stream
, "<");
4208 type_print (type
, "", stream
, -1);
4209 fprintf_filtered (stream
, " [0x%s]>",
4210 phex_nz (to_underlying (type_die
), 0));
4215 case DW_OP_entry_value
:
4216 case DW_OP_GNU_entry_value
:
4217 data
= safe_read_uleb128 (data
, end
, &ul
);
4218 fputc_filtered ('\n', stream
);
4219 disassemble_dwarf_expression (stream
, arch
, addr_size
, offset_size
,
4220 start
, data
, data
+ ul
, indent
+ 2,
4221 all
, per_cu
, per_objfile
);
4225 case DW_OP_GNU_parameter_ref
:
4226 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4228 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4232 case DW_OP_GNU_addr_index
:
4233 data
= safe_read_uleb128 (data
, end
, &ul
);
4234 ul
= dwarf2_read_addr_index (per_cu
, per_objfile
, ul
);
4235 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
4237 case DW_OP_GNU_const_index
:
4238 data
= safe_read_uleb128 (data
, end
, &ul
);
4239 ul
= dwarf2_read_addr_index (per_cu
, per_objfile
, ul
);
4240 fprintf_filtered (stream
, " %s", pulongest (ul
));
4243 case DW_OP_GNU_variable_value
:
4244 ul
= extract_unsigned_integer (data
, offset_size
,
4245 gdbarch_byte_order (arch
));
4246 data
+= offset_size
;
4247 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4251 fprintf_filtered (stream
, "\n");
4257 static bool dwarf_always_disassemble
;
4260 show_dwarf_always_disassemble (struct ui_file
*file
, int from_tty
,
4261 struct cmd_list_element
*c
, const char *value
)
4263 fprintf_filtered (file
,
4264 _("Whether to always disassemble "
4265 "DWARF expressions is %s.\n"),
4269 /* Describe a single location, which may in turn consist of multiple
4273 locexpr_describe_location_1 (struct symbol
*symbol
, CORE_ADDR addr
,
4274 struct ui_file
*stream
,
4275 const gdb_byte
*data
, size_t size
,
4276 unsigned int addr_size
,
4277 int offset_size
, dwarf2_per_cu_data
*per_cu
,
4278 dwarf2_per_objfile
*per_objfile
)
4280 const gdb_byte
*end
= data
+ size
;
4281 int first_piece
= 1, bad
= 0;
4282 objfile
*objfile
= per_objfile
->objfile
;
4286 const gdb_byte
*here
= data
;
4287 int disassemble
= 1;
4292 fprintf_filtered (stream
, _(", and "));
4294 if (!dwarf_always_disassemble
)
4296 data
= locexpr_describe_location_piece (symbol
, stream
,
4297 addr
, per_cu
, per_objfile
,
4298 data
, end
, addr_size
);
4299 /* If we printed anything, or if we have an empty piece,
4300 then don't disassemble. */
4302 || data
[0] == DW_OP_piece
4303 || data
[0] == DW_OP_bit_piece
)
4308 fprintf_filtered (stream
, _("a complex DWARF expression:\n"));
4309 data
= disassemble_dwarf_expression (stream
,
4311 addr_size
, offset_size
, data
,
4313 dwarf_always_disassemble
,
4314 per_cu
, per_objfile
);
4319 int empty
= data
== here
;
4322 fprintf_filtered (stream
, " ");
4323 if (data
[0] == DW_OP_piece
)
4327 data
= safe_read_uleb128 (data
+ 1, end
, &bytes
);
4330 fprintf_filtered (stream
, _("an empty %s-byte piece"),
4333 fprintf_filtered (stream
, _(" [%s-byte piece]"),
4336 else if (data
[0] == DW_OP_bit_piece
)
4338 uint64_t bits
, offset
;
4340 data
= safe_read_uleb128 (data
+ 1, end
, &bits
);
4341 data
= safe_read_uleb128 (data
, end
, &offset
);
4344 fprintf_filtered (stream
,
4345 _("an empty %s-bit piece"),
4348 fprintf_filtered (stream
,
4349 _(" [%s-bit piece, offset %s bits]"),
4350 pulongest (bits
), pulongest (offset
));
4360 if (bad
|| data
> end
)
4361 error (_("Corrupted DWARF2 expression for \"%s\"."),
4362 symbol
->print_name ());
4365 /* Print a natural-language description of SYMBOL to STREAM. This
4366 version is for a symbol with a single location. */
4369 locexpr_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4370 struct ui_file
*stream
)
4372 struct dwarf2_locexpr_baton
*dlbaton
4373 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4374 unsigned int addr_size
= dlbaton
->per_cu
->addr_size ();
4375 int offset_size
= dlbaton
->per_cu
->offset_size ();
4377 locexpr_describe_location_1 (symbol
, addr
, stream
,
4378 dlbaton
->data
, dlbaton
->size
,
4379 addr_size
, offset_size
,
4380 dlbaton
->per_cu
, dlbaton
->per_objfile
);
4383 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4384 any necessary bytecode in AX. */
4387 locexpr_tracepoint_var_ref (struct symbol
*symbol
, struct agent_expr
*ax
,
4388 struct axs_value
*value
)
4390 struct dwarf2_locexpr_baton
*dlbaton
4391 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4392 unsigned int addr_size
= dlbaton
->per_cu
->addr_size ();
4394 if (dlbaton
->size
== 0)
4395 value
->optimized_out
= 1;
4397 dwarf2_compile_expr_to_ax (ax
, value
, addr_size
, dlbaton
->data
,
4398 dlbaton
->data
+ dlbaton
->size
, dlbaton
->per_cu
,
4399 dlbaton
->per_objfile
);
4402 /* symbol_computed_ops 'generate_c_location' method. */
4405 locexpr_generate_c_location (struct symbol
*sym
, string_file
*stream
,
4406 struct gdbarch
*gdbarch
,
4407 unsigned char *registers_used
,
4408 CORE_ADDR pc
, const char *result_name
)
4410 struct dwarf2_locexpr_baton
*dlbaton
4411 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (sym
);
4412 unsigned int addr_size
= dlbaton
->per_cu
->addr_size ();
4414 if (dlbaton
->size
== 0)
4415 error (_("symbol \"%s\" is optimized out"), sym
->natural_name ());
4417 compile_dwarf_expr_to_c (stream
, result_name
,
4418 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4419 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4420 dlbaton
->per_cu
, dlbaton
->per_objfile
);
4423 /* The set of location functions used with the DWARF-2 expression
4425 const struct symbol_computed_ops dwarf2_locexpr_funcs
= {
4426 locexpr_read_variable
,
4427 locexpr_read_variable_at_entry
,
4428 locexpr_get_symbol_read_needs
,
4429 locexpr_describe_location
,
4430 0, /* location_has_loclist */
4431 locexpr_tracepoint_var_ref
,
4432 locexpr_generate_c_location
4436 /* Wrapper functions for location lists. These generally find
4437 the appropriate location expression and call something above. */
4439 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
4440 evaluator to calculate the location. */
4441 static struct value
*
4442 loclist_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
4444 struct dwarf2_loclist_baton
*dlbaton
4445 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4447 const gdb_byte
*data
;
4449 CORE_ADDR pc
= frame
? get_frame_address_in_block (frame
) : 0;
4451 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4452 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, data
, size
,
4458 /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
4459 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
4462 Function always returns non-NULL value, it may be marked optimized out if
4463 inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
4464 if it cannot resolve the parameter for any reason. */
4466 static struct value
*
4467 loclist_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
4469 struct dwarf2_loclist_baton
*dlbaton
4470 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4471 const gdb_byte
*data
;
4475 if (frame
== NULL
|| !get_frame_func_if_available (frame
, &pc
))
4476 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4478 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4480 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4482 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, data
, size
);
4485 /* Implementation of get_symbol_read_needs from
4486 symbol_computed_ops. */
4488 static enum symbol_needs_kind
4489 loclist_symbol_needs (struct symbol
*symbol
)
4491 /* If there's a location list, then assume we need to have a frame
4492 to choose the appropriate location expression. With tracking of
4493 global variables this is not necessarily true, but such tracking
4494 is disabled in GCC at the moment until we figure out how to
4497 return SYMBOL_NEEDS_FRAME
;
4500 /* Print a natural-language description of SYMBOL to STREAM. This
4501 version applies when there is a list of different locations, each
4502 with a specified address range. */
4505 loclist_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4506 struct ui_file
*stream
)
4508 struct dwarf2_loclist_baton
*dlbaton
4509 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4510 const gdb_byte
*loc_ptr
, *buf_end
;
4511 dwarf2_per_objfile
*per_objfile
= dlbaton
->per_objfile
;
4512 struct objfile
*objfile
= per_objfile
->objfile
;
4513 struct gdbarch
*gdbarch
= objfile
->arch ();
4514 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
4515 unsigned int addr_size
= dlbaton
->per_cu
->addr_size ();
4516 int offset_size
= dlbaton
->per_cu
->offset_size ();
4517 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
4518 /* Adjust base_address for relocatable objects. */
4519 CORE_ADDR base_offset
= objfile
->text_section_offset ();
4520 CORE_ADDR base_address
= dlbaton
->base_address
+ base_offset
;
4523 loc_ptr
= dlbaton
->data
;
4524 buf_end
= dlbaton
->data
+ dlbaton
->size
;
4526 fprintf_filtered (stream
, _("multi-location:\n"));
4528 /* Iterate through locations until we run out. */
4531 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
4533 enum debug_loc_kind kind
;
4534 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
4536 if (dlbaton
->per_cu
->version () < 5 && dlbaton
->from_dwo
)
4537 kind
= decode_debug_loc_dwo_addresses (dlbaton
->per_cu
,
4538 dlbaton
->per_objfile
,
4539 loc_ptr
, buf_end
, &new_ptr
,
4540 &low
, &high
, byte_order
);
4541 else if (dlbaton
->per_cu
->version () < 5)
4542 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
4544 byte_order
, addr_size
,
4547 kind
= decode_debug_loclists_addresses (dlbaton
->per_cu
,
4548 dlbaton
->per_objfile
,
4549 loc_ptr
, buf_end
, &new_ptr
,
4550 &low
, &high
, byte_order
,
4551 addr_size
, signed_addr_p
);
4555 case DEBUG_LOC_END_OF_LIST
:
4558 case DEBUG_LOC_BASE_ADDRESS
:
4559 base_address
= high
+ base_offset
;
4560 fprintf_filtered (stream
, _(" Base address %s"),
4561 paddress (gdbarch
, base_address
));
4563 case DEBUG_LOC_START_END
:
4564 case DEBUG_LOC_START_LENGTH
:
4565 case DEBUG_LOC_OFFSET_PAIR
:
4567 case DEBUG_LOC_BUFFER_OVERFLOW
:
4568 case DEBUG_LOC_INVALID_ENTRY
:
4569 error (_("Corrupted DWARF expression for symbol \"%s\"."),
4570 symbol
->print_name ());
4572 gdb_assert_not_reached ("bad debug_loc_kind");
4575 /* Otherwise, a location expression entry. */
4576 low
+= base_address
;
4577 high
+= base_address
;
4579 low
= gdbarch_adjust_dwarf2_addr (gdbarch
, low
);
4580 high
= gdbarch_adjust_dwarf2_addr (gdbarch
, high
);
4582 if (dlbaton
->per_cu
->version () < 5)
4584 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
4589 unsigned int bytes_read
;
4590 length
= read_unsigned_leb128 (NULL
, loc_ptr
, &bytes_read
);
4591 loc_ptr
+= bytes_read
;
4594 /* (It would improve readability to print only the minimum
4595 necessary digits of the second number of the range.) */
4596 fprintf_filtered (stream
, _(" Range %s-%s: "),
4597 paddress (gdbarch
, low
), paddress (gdbarch
, high
));
4599 /* Now describe this particular location. */
4600 locexpr_describe_location_1 (symbol
, low
, stream
, loc_ptr
, length
,
4601 addr_size
, offset_size
,
4602 dlbaton
->per_cu
, dlbaton
->per_objfile
);
4604 fprintf_filtered (stream
, "\n");
4610 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4611 any necessary bytecode in AX. */
4613 loclist_tracepoint_var_ref (struct symbol
*symbol
, struct agent_expr
*ax
,
4614 struct axs_value
*value
)
4616 struct dwarf2_loclist_baton
*dlbaton
4617 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4618 const gdb_byte
*data
;
4620 unsigned int addr_size
= dlbaton
->per_cu
->addr_size ();
4622 data
= dwarf2_find_location_expression (dlbaton
, &size
, ax
->scope
);
4624 value
->optimized_out
= 1;
4626 dwarf2_compile_expr_to_ax (ax
, value
, addr_size
, data
, data
+ size
,
4627 dlbaton
->per_cu
, dlbaton
->per_objfile
);
4630 /* symbol_computed_ops 'generate_c_location' method. */
4633 loclist_generate_c_location (struct symbol
*sym
, string_file
*stream
,
4634 struct gdbarch
*gdbarch
,
4635 unsigned char *registers_used
,
4636 CORE_ADDR pc
, const char *result_name
)
4638 struct dwarf2_loclist_baton
*dlbaton
4639 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (sym
);
4640 unsigned int addr_size
= dlbaton
->per_cu
->addr_size ();
4641 const gdb_byte
*data
;
4644 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4646 error (_("symbol \"%s\" is optimized out"), sym
->natural_name ());
4648 compile_dwarf_expr_to_c (stream
, result_name
,
4649 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4652 dlbaton
->per_objfile
);
4655 /* The set of location functions used with the DWARF-2 expression
4656 evaluator and location lists. */
4657 const struct symbol_computed_ops dwarf2_loclist_funcs
= {
4658 loclist_read_variable
,
4659 loclist_read_variable_at_entry
,
4660 loclist_symbol_needs
,
4661 loclist_describe_location
,
4662 1, /* location_has_loclist */
4663 loclist_tracepoint_var_ref
,
4664 loclist_generate_c_location
4667 void _initialize_dwarf2loc ();
4669 _initialize_dwarf2loc ()
4671 add_setshow_zuinteger_cmd ("entry-values", class_maintenance
,
4672 &entry_values_debug
,
4673 _("Set entry values and tail call frames "
4675 _("Show entry values and tail call frames "
4677 _("When non-zero, the process of determining "
4678 "parameter values from function entry point "
4679 "and tail call frames will be printed."),
4681 show_entry_values_debug
,
4682 &setdebuglist
, &showdebuglist
);
4684 add_setshow_boolean_cmd ("always-disassemble", class_obscure
,
4685 &dwarf_always_disassemble
, _("\
4686 Set whether `info address' always disassembles DWARF expressions."), _("\
4687 Show whether `info address' always disassembles DWARF expressions."), _("\
4688 When enabled, DWARF expressions are always printed in an assembly-like\n\
4689 syntax. When disabled, expressions will be printed in a more\n\
4690 conversational style, when possible."),
4692 show_dwarf_always_disassemble
,
4694 &show_dwarf_cmdlist
);