1 /* DWARF 2 location expression support for GDB.
3 Copyright (C) 2003-2017 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 "dwarf2expr.h"
38 #include "dwarf2loc.h"
39 #include "dwarf2-frame.h"
40 #include "compile/compile.h"
44 #include <unordered_set>
45 #include "common/underlying.h"
46 #include "common/byte-vector.h"
48 extern int dwarf_always_disassemble
;
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 /* Until these have formal names, we define these here.
65 ref: http://gcc.gnu.org/wiki/DebugFission
66 Each entry in .debug_loc.dwo begins with a byte that describes the entry,
67 and is then followed by data specific to that entry. */
71 /* Indicates the end of the list of entries. */
72 DEBUG_LOC_END_OF_LIST
= 0,
74 /* This is followed by an unsigned LEB128 number that is an index into
75 .debug_addr and specifies the base address for all following entries. */
76 DEBUG_LOC_BASE_ADDRESS
= 1,
78 /* This is followed by two unsigned LEB128 numbers that are indices into
79 .debug_addr and specify the beginning and ending addresses, and then
80 a normal location expression as in .debug_loc. */
81 DEBUG_LOC_START_END
= 2,
83 /* This is followed by an unsigned LEB128 number that is an index into
84 .debug_addr and specifies the beginning address, and a 4 byte unsigned
85 number that specifies the length, and then a normal location expression
87 DEBUG_LOC_START_LENGTH
= 3,
89 /* An internal value indicating there is insufficient data. */
90 DEBUG_LOC_BUFFER_OVERFLOW
= -1,
92 /* An internal value indicating an invalid kind of entry was found. */
93 DEBUG_LOC_INVALID_ENTRY
= -2
96 /* Helper function which throws an error if a synthetic pointer is
100 invalid_synthetic_pointer (void)
102 error (_("access outside bounds of object "
103 "referenced via synthetic pointer"));
106 /* Decode the addresses in a non-dwo .debug_loc entry.
107 A pointer to the next byte to examine is returned in *NEW_PTR.
108 The encoded low,high addresses are return in *LOW,*HIGH.
109 The result indicates the kind of entry found. */
111 static enum debug_loc_kind
112 decode_debug_loc_addresses (const gdb_byte
*loc_ptr
, const gdb_byte
*buf_end
,
113 const gdb_byte
**new_ptr
,
114 CORE_ADDR
*low
, CORE_ADDR
*high
,
115 enum bfd_endian byte_order
,
116 unsigned int addr_size
,
119 CORE_ADDR base_mask
= ~(~(CORE_ADDR
)1 << (addr_size
* 8 - 1));
121 if (buf_end
- loc_ptr
< 2 * addr_size
)
122 return DEBUG_LOC_BUFFER_OVERFLOW
;
125 *low
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
127 *low
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
128 loc_ptr
+= addr_size
;
131 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
133 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
134 loc_ptr
+= addr_size
;
138 /* A base-address-selection entry. */
139 if ((*low
& base_mask
) == base_mask
)
140 return DEBUG_LOC_BASE_ADDRESS
;
142 /* An end-of-list entry. */
143 if (*low
== 0 && *high
== 0)
144 return DEBUG_LOC_END_OF_LIST
;
146 return DEBUG_LOC_START_END
;
149 /* Decode the addresses in .debug_loclists entry.
150 A pointer to the next byte to examine is returned in *NEW_PTR.
151 The encoded low,high addresses are return in *LOW,*HIGH.
152 The result indicates the kind of entry found. */
154 static enum debug_loc_kind
155 decode_debug_loclists_addresses (struct dwarf2_per_cu_data
*per_cu
,
156 const gdb_byte
*loc_ptr
,
157 const gdb_byte
*buf_end
,
158 const gdb_byte
**new_ptr
,
159 CORE_ADDR
*low
, CORE_ADDR
*high
,
160 enum bfd_endian byte_order
,
161 unsigned int addr_size
,
166 if (loc_ptr
== buf_end
)
167 return DEBUG_LOC_BUFFER_OVERFLOW
;
171 case DW_LLE_end_of_list
:
173 return DEBUG_LOC_END_OF_LIST
;
174 case DW_LLE_base_address
:
175 if (loc_ptr
+ addr_size
> buf_end
)
176 return DEBUG_LOC_BUFFER_OVERFLOW
;
178 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
180 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
181 loc_ptr
+= addr_size
;
183 return DEBUG_LOC_BASE_ADDRESS
;
184 case DW_LLE_offset_pair
:
185 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
187 return DEBUG_LOC_BUFFER_OVERFLOW
;
189 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
191 return DEBUG_LOC_BUFFER_OVERFLOW
;
194 return DEBUG_LOC_START_END
;
196 return DEBUG_LOC_INVALID_ENTRY
;
200 /* Decode the addresses in .debug_loc.dwo entry.
201 A pointer to the next byte to examine is returned in *NEW_PTR.
202 The encoded low,high addresses are return in *LOW,*HIGH.
203 The result indicates the kind of entry found. */
205 static enum debug_loc_kind
206 decode_debug_loc_dwo_addresses (struct dwarf2_per_cu_data
*per_cu
,
207 const gdb_byte
*loc_ptr
,
208 const gdb_byte
*buf_end
,
209 const gdb_byte
**new_ptr
,
210 CORE_ADDR
*low
, CORE_ADDR
*high
,
211 enum bfd_endian byte_order
)
213 uint64_t low_index
, high_index
;
215 if (loc_ptr
== buf_end
)
216 return DEBUG_LOC_BUFFER_OVERFLOW
;
220 case DW_LLE_GNU_end_of_list_entry
:
222 return DEBUG_LOC_END_OF_LIST
;
223 case DW_LLE_GNU_base_address_selection_entry
:
225 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
227 return DEBUG_LOC_BUFFER_OVERFLOW
;
228 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
230 return DEBUG_LOC_BASE_ADDRESS
;
231 case DW_LLE_GNU_start_end_entry
:
232 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
234 return DEBUG_LOC_BUFFER_OVERFLOW
;
235 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
236 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
238 return DEBUG_LOC_BUFFER_OVERFLOW
;
239 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
241 return DEBUG_LOC_START_END
;
242 case DW_LLE_GNU_start_length_entry
:
243 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
245 return DEBUG_LOC_BUFFER_OVERFLOW
;
246 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
247 if (loc_ptr
+ 4 > buf_end
)
248 return DEBUG_LOC_BUFFER_OVERFLOW
;
250 *high
+= extract_unsigned_integer (loc_ptr
, 4, byte_order
);
251 *new_ptr
= loc_ptr
+ 4;
252 return DEBUG_LOC_START_LENGTH
;
254 return DEBUG_LOC_INVALID_ENTRY
;
258 /* A function for dealing with location lists. Given a
259 symbol baton (BATON) and a pc value (PC), find the appropriate
260 location expression, set *LOCEXPR_LENGTH, and return a pointer
261 to the beginning of the expression. Returns NULL on failure.
263 For now, only return the first matching location expression; there
264 can be more than one in the list. */
267 dwarf2_find_location_expression (struct dwarf2_loclist_baton
*baton
,
268 size_t *locexpr_length
, CORE_ADDR pc
)
270 struct objfile
*objfile
= dwarf2_per_cu_objfile (baton
->per_cu
);
271 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
272 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
273 unsigned int addr_size
= dwarf2_per_cu_addr_size (baton
->per_cu
);
274 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
275 /* Adjust base_address for relocatable objects. */
276 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (baton
->per_cu
);
277 CORE_ADDR base_address
= baton
->base_address
+ base_offset
;
278 const gdb_byte
*loc_ptr
, *buf_end
;
280 loc_ptr
= baton
->data
;
281 buf_end
= baton
->data
+ baton
->size
;
285 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
287 enum debug_loc_kind kind
;
288 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
291 kind
= decode_debug_loc_dwo_addresses (baton
->per_cu
,
292 loc_ptr
, buf_end
, &new_ptr
,
293 &low
, &high
, byte_order
);
294 else if (dwarf2_version (baton
->per_cu
) < 5)
295 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
297 byte_order
, addr_size
,
300 kind
= decode_debug_loclists_addresses (baton
->per_cu
,
301 loc_ptr
, buf_end
, &new_ptr
,
302 &low
, &high
, byte_order
,
303 addr_size
, signed_addr_p
);
308 case DEBUG_LOC_END_OF_LIST
:
311 case DEBUG_LOC_BASE_ADDRESS
:
312 base_address
= high
+ base_offset
;
314 case DEBUG_LOC_START_END
:
315 case DEBUG_LOC_START_LENGTH
:
317 case DEBUG_LOC_BUFFER_OVERFLOW
:
318 case DEBUG_LOC_INVALID_ENTRY
:
319 error (_("dwarf2_find_location_expression: "
320 "Corrupted DWARF expression."));
322 gdb_assert_not_reached ("bad debug_loc_kind");
325 /* Otherwise, a location expression entry.
326 If the entry is from a DWO, don't add base address: the entry is from
327 .debug_addr which already has the DWARF "base address". We still add
328 base_offset in case we're debugging a PIE executable. */
337 high
+= base_address
;
340 if (dwarf2_version (baton
->per_cu
) < 5)
342 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
347 unsigned int bytes_read
;
349 length
= read_unsigned_leb128 (NULL
, loc_ptr
, &bytes_read
);
350 loc_ptr
+= bytes_read
;
353 if (low
== high
&& pc
== low
)
355 /* This is entry PC record present only at entry point
356 of a function. Verify it is really the function entry point. */
358 const struct block
*pc_block
= block_for_pc (pc
);
359 struct symbol
*pc_func
= NULL
;
362 pc_func
= block_linkage_function (pc_block
);
364 if (pc_func
&& pc
== BLOCK_START (SYMBOL_BLOCK_VALUE (pc_func
)))
366 *locexpr_length
= length
;
371 if (pc
>= low
&& pc
< high
)
373 *locexpr_length
= length
;
381 /* This is the baton used when performing dwarf2 expression
383 struct dwarf_expr_baton
385 struct frame_info
*frame
;
386 struct dwarf2_per_cu_data
*per_cu
;
387 CORE_ADDR obj_address
;
390 /* Implement find_frame_base_location method for LOC_BLOCK functions using
391 DWARF expression for its DW_AT_frame_base. */
394 locexpr_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
395 const gdb_byte
**start
, size_t *length
)
397 struct dwarf2_locexpr_baton
*symbaton
398 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
400 *length
= symbaton
->size
;
401 *start
= symbaton
->data
;
404 /* Implement the struct symbol_block_ops::get_frame_base method for
405 LOC_BLOCK functions using a DWARF expression as its DW_AT_frame_base. */
408 locexpr_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
410 struct gdbarch
*gdbarch
;
412 struct dwarf2_locexpr_baton
*dlbaton
;
413 const gdb_byte
*start
;
415 struct value
*result
;
417 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
418 Thus, it's supposed to provide the find_frame_base_location method as
420 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
422 gdbarch
= get_frame_arch (frame
);
423 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
424 dlbaton
= (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
426 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
427 (framefunc
, get_frame_pc (frame
), &start
, &length
);
428 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
431 /* The DW_AT_frame_base attribute contains a location description which
432 computes the base address itself. However, the call to
433 dwarf2_evaluate_loc_desc returns a value representing a variable at
434 that address. The frame base address is thus this variable's
436 return value_address (result
);
439 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
440 function uses DWARF expression for its DW_AT_frame_base. */
442 const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs
=
444 locexpr_find_frame_base_location
,
445 locexpr_get_frame_base
448 /* Implement find_frame_base_location method for LOC_BLOCK functions using
449 DWARF location list for its DW_AT_frame_base. */
452 loclist_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
453 const gdb_byte
**start
, size_t *length
)
455 struct dwarf2_loclist_baton
*symbaton
456 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
458 *start
= dwarf2_find_location_expression (symbaton
, length
, pc
);
461 /* Implement the struct symbol_block_ops::get_frame_base method for
462 LOC_BLOCK functions using a DWARF location list as its DW_AT_frame_base. */
465 loclist_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
467 struct gdbarch
*gdbarch
;
469 struct dwarf2_loclist_baton
*dlbaton
;
470 const gdb_byte
*start
;
472 struct value
*result
;
474 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
475 Thus, it's supposed to provide the find_frame_base_location method as
477 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
479 gdbarch
= get_frame_arch (frame
);
480 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
481 dlbaton
= (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
483 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
484 (framefunc
, get_frame_pc (frame
), &start
, &length
);
485 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
488 /* The DW_AT_frame_base attribute contains a location description which
489 computes the base address itself. However, the call to
490 dwarf2_evaluate_loc_desc returns a value representing a variable at
491 that address. The frame base address is thus this variable's
493 return value_address (result
);
496 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
497 function uses DWARF location list for its DW_AT_frame_base. */
499 const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs
=
501 loclist_find_frame_base_location
,
502 loclist_get_frame_base
505 /* See dwarf2loc.h. */
508 func_get_frame_base_dwarf_block (struct symbol
*framefunc
, CORE_ADDR pc
,
509 const gdb_byte
**start
, size_t *length
)
511 if (SYMBOL_BLOCK_OPS (framefunc
) != NULL
)
513 const struct symbol_block_ops
*ops_block
= SYMBOL_BLOCK_OPS (framefunc
);
515 ops_block
->find_frame_base_location (framefunc
, pc
, start
, length
);
521 error (_("Could not find the frame base for \"%s\"."),
522 SYMBOL_NATURAL_NAME (framefunc
));
526 get_frame_pc_for_per_cu_dwarf_call (void *baton
)
528 dwarf_expr_context
*ctx
= (dwarf_expr_context
*) baton
;
530 return ctx
->get_frame_pc ();
534 per_cu_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
,
535 struct dwarf2_per_cu_data
*per_cu
)
537 struct dwarf2_locexpr_baton block
;
539 block
= dwarf2_fetch_die_loc_cu_off (die_offset
, per_cu
,
540 get_frame_pc_for_per_cu_dwarf_call
,
543 /* DW_OP_call_ref is currently not supported. */
544 gdb_assert (block
.per_cu
== per_cu
);
546 ctx
->eval (block
.data
, block
.size
);
549 class dwarf_evaluate_loc_desc
: public dwarf_expr_context
553 struct frame_info
*frame
;
554 struct dwarf2_per_cu_data
*per_cu
;
555 CORE_ADDR obj_address
;
557 /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for
558 the frame in BATON. */
560 CORE_ADDR
get_frame_cfa () OVERRIDE
562 return dwarf2_frame_cfa (frame
);
565 /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for
566 the frame in BATON. */
568 CORE_ADDR
get_frame_pc () OVERRIDE
570 return get_frame_address_in_block (frame
);
573 /* Using the objfile specified in BATON, find the address for the
574 current thread's thread-local storage with offset OFFSET. */
575 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
577 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
579 return target_translate_tls_address (objfile
, offset
);
582 /* Helper interface of per_cu_dwarf_call for
583 dwarf2_evaluate_loc_desc. */
585 void dwarf_call (cu_offset die_offset
) OVERRIDE
587 per_cu_dwarf_call (this, die_offset
, per_cu
);
590 struct type
*get_base_type (cu_offset die_offset
, int size
) OVERRIDE
592 struct type
*result
= dwarf2_get_die_type (die_offset
, per_cu
);
594 error (_("Could not find type for DW_OP_const_type"));
595 if (size
!= 0 && TYPE_LENGTH (result
) != size
)
596 error (_("DW_OP_const_type has different sizes for type and data"));
600 /* Callback function for dwarf2_evaluate_loc_desc.
601 Fetch the address indexed by DW_OP_GNU_addr_index. */
603 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
605 return dwarf2_read_addr_index (per_cu
, index
);
608 /* Callback function for get_object_address. Return the address of the VLA
611 CORE_ADDR
get_object_address () OVERRIDE
613 if (obj_address
== 0)
614 error (_("Location address is not set."));
618 /* Execute DWARF block of call_site_parameter which matches KIND and
619 KIND_U. Choose DEREF_SIZE value of that parameter. Search
620 caller of this objects's frame.
622 The caller can be from a different CU - per_cu_dwarf_call
623 implementation can be more simple as it does not support cross-CU
626 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
627 union call_site_parameter_u kind_u
,
628 int deref_size
) OVERRIDE
630 struct frame_info
*caller_frame
;
631 struct dwarf2_per_cu_data
*caller_per_cu
;
632 struct call_site_parameter
*parameter
;
633 const gdb_byte
*data_src
;
636 caller_frame
= get_prev_frame (frame
);
638 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
640 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
641 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
643 /* DEREF_SIZE size is not verified here. */
644 if (data_src
== NULL
)
645 throw_error (NO_ENTRY_VALUE_ERROR
,
646 _("Cannot resolve DW_AT_call_data_value"));
648 scoped_restore save_frame
= make_scoped_restore (&this->frame
,
650 scoped_restore save_per_cu
= make_scoped_restore (&this->per_cu
,
652 scoped_restore save_obj_addr
= make_scoped_restore (&this->obj_address
,
655 scoped_restore save_arch
= make_scoped_restore (&this->gdbarch
);
657 = get_objfile_arch (dwarf2_per_cu_objfile (per_cu
));
658 scoped_restore save_addr_size
= make_scoped_restore (&this->addr_size
);
659 this->addr_size
= dwarf2_per_cu_addr_size (per_cu
);
660 scoped_restore save_offset
= make_scoped_restore (&this->offset
);
661 this->offset
= dwarf2_per_cu_text_offset (per_cu
);
663 this->eval (data_src
, size
);
666 /* Using the frame specified in BATON, find the location expression
667 describing the frame base. Return a pointer to it in START and
668 its length in LENGTH. */
669 void get_frame_base (const gdb_byte
**start
, size_t * length
) OVERRIDE
671 /* FIXME: cagney/2003-03-26: This code should be using
672 get_frame_base_address(), and then implement a dwarf2 specific
674 struct symbol
*framefunc
;
675 const struct block
*bl
= get_frame_block (frame
, NULL
);
678 error (_("frame address is not available."));
680 /* Use block_linkage_function, which returns a real (not inlined)
681 function, instead of get_frame_function, which may return an
683 framefunc
= block_linkage_function (bl
);
685 /* If we found a frame-relative symbol then it was certainly within
686 some function associated with a frame. If we can't find the frame,
687 something has gone wrong. */
688 gdb_assert (framefunc
!= NULL
);
690 func_get_frame_base_dwarf_block (framefunc
,
691 get_frame_address_in_block (frame
),
695 /* Read memory at ADDR (length LEN) into BUF. */
697 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
699 read_memory (addr
, buf
, len
);
702 /* Using the frame specified in BATON, return the value of register
703 REGNUM, treated as a pointer. */
704 CORE_ADDR
read_addr_from_reg (int dwarf_regnum
) OVERRIDE
706 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
707 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
709 return address_from_register (regnum
, frame
);
712 /* Implement "get_reg_value" callback. */
714 struct value
*get_reg_value (struct type
*type
, int dwarf_regnum
) OVERRIDE
716 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
717 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
719 return value_from_register (type
, regnum
, frame
);
723 /* See dwarf2loc.h. */
725 unsigned int entry_values_debug
= 0;
727 /* Helper to set entry_values_debug. */
730 show_entry_values_debug (struct ui_file
*file
, int from_tty
,
731 struct cmd_list_element
*c
, const char *value
)
733 fprintf_filtered (file
,
734 _("Entry values and tail call frames debugging is %s.\n"),
738 /* Find DW_TAG_call_site's DW_AT_call_target address.
739 CALLER_FRAME (for registers) can be NULL if it is not known. This function
740 always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */
743 call_site_to_target_addr (struct gdbarch
*call_site_gdbarch
,
744 struct call_site
*call_site
,
745 struct frame_info
*caller_frame
)
747 switch (FIELD_LOC_KIND (call_site
->target
))
749 case FIELD_LOC_KIND_DWARF_BLOCK
:
751 struct dwarf2_locexpr_baton
*dwarf_block
;
753 struct type
*caller_core_addr_type
;
754 struct gdbarch
*caller_arch
;
756 dwarf_block
= FIELD_DWARF_BLOCK (call_site
->target
);
757 if (dwarf_block
== NULL
)
759 struct bound_minimal_symbol msym
;
761 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
762 throw_error (NO_ENTRY_VALUE_ERROR
,
763 _("DW_AT_call_target is not specified at %s in %s"),
764 paddress (call_site_gdbarch
, call_site
->pc
),
765 (msym
.minsym
== NULL
? "???"
766 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
769 if (caller_frame
== NULL
)
771 struct bound_minimal_symbol msym
;
773 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
774 throw_error (NO_ENTRY_VALUE_ERROR
,
775 _("DW_AT_call_target DWARF block resolving "
776 "requires known frame which is currently not "
777 "available at %s in %s"),
778 paddress (call_site_gdbarch
, call_site
->pc
),
779 (msym
.minsym
== NULL
? "???"
780 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
783 caller_arch
= get_frame_arch (caller_frame
);
784 caller_core_addr_type
= builtin_type (caller_arch
)->builtin_func_ptr
;
785 val
= dwarf2_evaluate_loc_desc (caller_core_addr_type
, caller_frame
,
786 dwarf_block
->data
, dwarf_block
->size
,
787 dwarf_block
->per_cu
);
788 /* DW_AT_call_target is a DWARF expression, not a DWARF location. */
789 if (VALUE_LVAL (val
) == lval_memory
)
790 return value_address (val
);
792 return value_as_address (val
);
795 case FIELD_LOC_KIND_PHYSNAME
:
797 const char *physname
;
798 struct bound_minimal_symbol msym
;
800 physname
= FIELD_STATIC_PHYSNAME (call_site
->target
);
802 /* Handle both the mangled and demangled PHYSNAME. */
803 msym
= lookup_minimal_symbol (physname
, NULL
, NULL
);
804 if (msym
.minsym
== NULL
)
806 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
807 throw_error (NO_ENTRY_VALUE_ERROR
,
808 _("Cannot find function \"%s\" for a call site target "
810 physname
, paddress (call_site_gdbarch
, call_site
->pc
),
811 (msym
.minsym
== NULL
? "???"
812 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
815 return BMSYMBOL_VALUE_ADDRESS (msym
);
818 case FIELD_LOC_KIND_PHYSADDR
:
819 return FIELD_STATIC_PHYSADDR (call_site
->target
);
822 internal_error (__FILE__
, __LINE__
, _("invalid call site target kind"));
826 /* Convert function entry point exact address ADDR to the function which is
827 compliant with TAIL_CALL_LIST_COMPLETE condition. Throw
828 NO_ENTRY_VALUE_ERROR otherwise. */
830 static struct symbol
*
831 func_addr_to_tail_call_list (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
833 struct symbol
*sym
= find_pc_function (addr
);
836 if (sym
== NULL
|| BLOCK_START (SYMBOL_BLOCK_VALUE (sym
)) != addr
)
837 throw_error (NO_ENTRY_VALUE_ERROR
,
838 _("DW_TAG_call_site resolving failed to find function "
839 "name for address %s"),
840 paddress (gdbarch
, addr
));
842 type
= SYMBOL_TYPE (sym
);
843 gdb_assert (TYPE_CODE (type
) == TYPE_CODE_FUNC
);
844 gdb_assert (TYPE_SPECIFIC_FIELD (type
) == TYPE_SPECIFIC_FUNC
);
849 /* Verify function with entry point exact address ADDR can never call itself
850 via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it
851 can call itself via tail calls.
853 If a funtion can tail call itself its entry value based parameters are
854 unreliable. There is no verification whether the value of some/all
855 parameters is unchanged through the self tail call, we expect if there is
856 a self tail call all the parameters can be modified. */
859 func_verify_no_selftailcall (struct gdbarch
*gdbarch
, CORE_ADDR verify_addr
)
863 /* The verification is completely unordered. Track here function addresses
864 which still need to be iterated. */
865 std::vector
<CORE_ADDR
> todo
;
867 /* Track here CORE_ADDRs which were already visited. */
868 std::unordered_set
<CORE_ADDR
> addr_hash
;
870 todo
.push_back (verify_addr
);
871 while (!todo
.empty ())
873 struct symbol
*func_sym
;
874 struct call_site
*call_site
;
879 func_sym
= func_addr_to_tail_call_list (gdbarch
, addr
);
881 for (call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym
));
882 call_site
; call_site
= call_site
->tail_call_next
)
884 CORE_ADDR target_addr
;
886 /* CALLER_FRAME with registers is not available for tail-call jumped
888 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
890 if (target_addr
== verify_addr
)
892 struct bound_minimal_symbol msym
;
894 msym
= lookup_minimal_symbol_by_pc (verify_addr
);
895 throw_error (NO_ENTRY_VALUE_ERROR
,
896 _("DW_OP_entry_value resolving has found "
897 "function \"%s\" at %s can call itself via tail "
899 (msym
.minsym
== NULL
? "???"
900 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
901 paddress (gdbarch
, verify_addr
));
904 if (addr_hash
.insert (target_addr
).second
)
905 todo
.push_back (target_addr
);
910 /* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for
911 ENTRY_VALUES_DEBUG. */
914 tailcall_dump (struct gdbarch
*gdbarch
, const struct call_site
*call_site
)
916 CORE_ADDR addr
= call_site
->pc
;
917 struct bound_minimal_symbol msym
= lookup_minimal_symbol_by_pc (addr
- 1);
919 fprintf_unfiltered (gdb_stdlog
, " %s(%s)", paddress (gdbarch
, addr
),
920 (msym
.minsym
== NULL
? "???"
921 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
925 /* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP
926 only top callers and bottom callees which are present in both. GDBARCH is
927 used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are
928 no remaining possibilities to provide unambiguous non-trivial result.
929 RESULTP should point to NULL on the first (initialization) call. Caller is
930 responsible for xfree of any RESULTP data. */
933 chain_candidate (struct gdbarch
*gdbarch
,
934 gdb::unique_xmalloc_ptr
<struct call_site_chain
> *resultp
,
935 std::vector
<struct call_site
*> *chain
)
937 long length
= chain
->size ();
938 int callers
, callees
, idx
;
940 if (*resultp
== NULL
)
942 /* Create the initial chain containing all the passed PCs. */
944 struct call_site_chain
*result
945 = ((struct call_site_chain
*)
946 xmalloc (sizeof (*result
)
947 + sizeof (*result
->call_site
) * (length
- 1)));
948 result
->length
= length
;
949 result
->callers
= result
->callees
= length
;
950 if (!chain
->empty ())
951 memcpy (result
->call_site
, chain
->data (),
952 sizeof (*result
->call_site
) * length
);
953 resultp
->reset (result
);
955 if (entry_values_debug
)
957 fprintf_unfiltered (gdb_stdlog
, "tailcall: initial:");
958 for (idx
= 0; idx
< length
; idx
++)
959 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
960 fputc_unfiltered ('\n', gdb_stdlog
);
966 if (entry_values_debug
)
968 fprintf_unfiltered (gdb_stdlog
, "tailcall: compare:");
969 for (idx
= 0; idx
< length
; idx
++)
970 tailcall_dump (gdbarch
, chain
->at (idx
));
971 fputc_unfiltered ('\n', gdb_stdlog
);
974 /* Intersect callers. */
976 callers
= std::min ((long) (*resultp
)->callers
, length
);
977 for (idx
= 0; idx
< callers
; idx
++)
978 if ((*resultp
)->call_site
[idx
] != chain
->at (idx
))
980 (*resultp
)->callers
= idx
;
984 /* Intersect callees. */
986 callees
= std::min ((long) (*resultp
)->callees
, length
);
987 for (idx
= 0; idx
< callees
; idx
++)
988 if ((*resultp
)->call_site
[(*resultp
)->length
- 1 - idx
]
989 != chain
->at (length
- 1 - idx
))
991 (*resultp
)->callees
= idx
;
995 if (entry_values_debug
)
997 fprintf_unfiltered (gdb_stdlog
, "tailcall: reduced:");
998 for (idx
= 0; idx
< (*resultp
)->callers
; idx
++)
999 tailcall_dump (gdbarch
, (*resultp
)->call_site
[idx
]);
1000 fputs_unfiltered (" |", gdb_stdlog
);
1001 for (idx
= 0; idx
< (*resultp
)->callees
; idx
++)
1002 tailcall_dump (gdbarch
,
1003 (*resultp
)->call_site
[(*resultp
)->length
1004 - (*resultp
)->callees
+ idx
]);
1005 fputc_unfiltered ('\n', gdb_stdlog
);
1008 if ((*resultp
)->callers
== 0 && (*resultp
)->callees
== 0)
1010 /* There are no common callers or callees. It could be also a direct
1011 call (which has length 0) with ambiguous possibility of an indirect
1012 call - CALLERS == CALLEES == 0 is valid during the first allocation
1013 but any subsequence processing of such entry means ambiguity. */
1014 resultp
->reset (NULL
);
1018 /* See call_site_find_chain_1 why there is no way to reach the bottom callee
1019 PC again. In such case there must be two different code paths to reach
1020 it. CALLERS + CALLEES equal to LENGTH in the case of self tail-call. */
1021 gdb_assert ((*resultp
)->callers
+ (*resultp
)->callees
<= (*resultp
)->length
);
1024 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1025 assumed frames between them use GDBARCH. Use depth first search so we can
1026 keep single CHAIN of call_site's back to CALLER_PC. Function recursion
1027 would have needless GDB stack overhead. Caller is responsible for xfree of
1028 the returned result. Any unreliability results in thrown
1029 NO_ENTRY_VALUE_ERROR. */
1031 static struct call_site_chain
*
1032 call_site_find_chain_1 (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1033 CORE_ADDR callee_pc
)
1035 CORE_ADDR save_callee_pc
= callee_pc
;
1036 gdb::unique_xmalloc_ptr
<struct call_site_chain
> retval
;
1037 struct call_site
*call_site
;
1039 /* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's
1040 call_site nor any possible call_site at CALLEE_PC's function is there.
1041 Any CALL_SITE in CHAIN will be iterated to its siblings - via
1042 TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */
1043 std::vector
<struct call_site
*> chain
;
1045 /* We are not interested in the specific PC inside the callee function. */
1046 callee_pc
= get_pc_function_start (callee_pc
);
1048 throw_error (NO_ENTRY_VALUE_ERROR
, _("Unable to find function for PC %s"),
1049 paddress (gdbarch
, save_callee_pc
));
1051 /* Mark CALL_SITEs so we do not visit the same ones twice. */
1052 std::unordered_set
<CORE_ADDR
> addr_hash
;
1054 /* Do not push CALL_SITE to CHAIN. Push there only the first tail call site
1055 at the target's function. All the possible tail call sites in the
1056 target's function will get iterated as already pushed into CHAIN via their
1058 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1062 CORE_ADDR target_func_addr
;
1063 struct call_site
*target_call_site
;
1065 /* CALLER_FRAME with registers is not available for tail-call jumped
1067 target_func_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
1069 if (target_func_addr
== callee_pc
)
1071 chain_candidate (gdbarch
, &retval
, &chain
);
1075 /* There is no way to reach CALLEE_PC again as we would prevent
1076 entering it twice as being already marked in ADDR_HASH. */
1077 target_call_site
= NULL
;
1081 struct symbol
*target_func
;
1083 target_func
= func_addr_to_tail_call_list (gdbarch
, target_func_addr
);
1084 target_call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func
));
1089 /* Attempt to visit TARGET_CALL_SITE. */
1091 if (target_call_site
)
1093 if (addr_hash
.insert (target_call_site
->pc
).second
)
1095 /* Successfully entered TARGET_CALL_SITE. */
1097 chain
.push_back (target_call_site
);
1102 /* Backtrack (without revisiting the originating call_site). Try the
1103 callers's sibling; if there isn't any try the callers's callers's
1106 target_call_site
= NULL
;
1107 while (!chain
.empty ())
1109 call_site
= chain
.back ();
1112 size_t removed
= addr_hash
.erase (call_site
->pc
);
1113 gdb_assert (removed
== 1);
1115 target_call_site
= call_site
->tail_call_next
;
1116 if (target_call_site
)
1120 while (target_call_site
);
1125 call_site
= chain
.back ();
1130 struct bound_minimal_symbol msym_caller
, msym_callee
;
1132 msym_caller
= lookup_minimal_symbol_by_pc (caller_pc
);
1133 msym_callee
= lookup_minimal_symbol_by_pc (callee_pc
);
1134 throw_error (NO_ENTRY_VALUE_ERROR
,
1135 _("There are no unambiguously determinable intermediate "
1136 "callers or callees between caller function \"%s\" at %s "
1137 "and callee function \"%s\" at %s"),
1138 (msym_caller
.minsym
== NULL
1139 ? "???" : MSYMBOL_PRINT_NAME (msym_caller
.minsym
)),
1140 paddress (gdbarch
, caller_pc
),
1141 (msym_callee
.minsym
== NULL
1142 ? "???" : MSYMBOL_PRINT_NAME (msym_callee
.minsym
)),
1143 paddress (gdbarch
, callee_pc
));
1146 return retval
.release ();
1149 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1150 assumed frames between them use GDBARCH. If valid call_site_chain cannot be
1151 constructed return NULL. Caller is responsible for xfree of the returned
1154 struct call_site_chain
*
1155 call_site_find_chain (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1156 CORE_ADDR callee_pc
)
1158 struct call_site_chain
*retval
= NULL
;
1162 retval
= call_site_find_chain_1 (gdbarch
, caller_pc
, callee_pc
);
1164 CATCH (e
, RETURN_MASK_ERROR
)
1166 if (e
.error
== NO_ENTRY_VALUE_ERROR
)
1168 if (entry_values_debug
)
1169 exception_print (gdb_stdout
, e
);
1174 throw_exception (e
);
1181 /* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */
1184 call_site_parameter_matches (struct call_site_parameter
*parameter
,
1185 enum call_site_parameter_kind kind
,
1186 union call_site_parameter_u kind_u
)
1188 if (kind
== parameter
->kind
)
1191 case CALL_SITE_PARAMETER_DWARF_REG
:
1192 return kind_u
.dwarf_reg
== parameter
->u
.dwarf_reg
;
1193 case CALL_SITE_PARAMETER_FB_OFFSET
:
1194 return kind_u
.fb_offset
== parameter
->u
.fb_offset
;
1195 case CALL_SITE_PARAMETER_PARAM_OFFSET
:
1196 return kind_u
.param_cu_off
== parameter
->u
.param_cu_off
;
1201 /* Fetch call_site_parameter from caller matching KIND and KIND_U.
1202 FRAME is for callee.
1204 Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
1207 static struct call_site_parameter
*
1208 dwarf_expr_reg_to_entry_parameter (struct frame_info
*frame
,
1209 enum call_site_parameter_kind kind
,
1210 union call_site_parameter_u kind_u
,
1211 struct dwarf2_per_cu_data
**per_cu_return
)
1213 CORE_ADDR func_addr
, caller_pc
;
1214 struct gdbarch
*gdbarch
;
1215 struct frame_info
*caller_frame
;
1216 struct call_site
*call_site
;
1218 /* Initialize it just to avoid a GCC false warning. */
1219 struct call_site_parameter
*parameter
= NULL
;
1220 CORE_ADDR target_addr
;
1222 while (get_frame_type (frame
) == INLINE_FRAME
)
1224 frame
= get_prev_frame (frame
);
1225 gdb_assert (frame
!= NULL
);
1228 func_addr
= get_frame_func (frame
);
1229 gdbarch
= get_frame_arch (frame
);
1230 caller_frame
= get_prev_frame (frame
);
1231 if (gdbarch
!= frame_unwind_arch (frame
))
1233 struct bound_minimal_symbol msym
1234 = lookup_minimal_symbol_by_pc (func_addr
);
1235 struct gdbarch
*caller_gdbarch
= frame_unwind_arch (frame
);
1237 throw_error (NO_ENTRY_VALUE_ERROR
,
1238 _("DW_OP_entry_value resolving callee gdbarch %s "
1239 "(of %s (%s)) does not match caller gdbarch %s"),
1240 gdbarch_bfd_arch_info (gdbarch
)->printable_name
,
1241 paddress (gdbarch
, func_addr
),
1242 (msym
.minsym
== NULL
? "???"
1243 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
1244 gdbarch_bfd_arch_info (caller_gdbarch
)->printable_name
);
1247 if (caller_frame
== NULL
)
1249 struct bound_minimal_symbol msym
1250 = lookup_minimal_symbol_by_pc (func_addr
);
1252 throw_error (NO_ENTRY_VALUE_ERROR
, _("DW_OP_entry_value resolving "
1253 "requires caller of %s (%s)"),
1254 paddress (gdbarch
, func_addr
),
1255 (msym
.minsym
== NULL
? "???"
1256 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
1258 caller_pc
= get_frame_pc (caller_frame
);
1259 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1261 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, caller_frame
);
1262 if (target_addr
!= func_addr
)
1264 struct minimal_symbol
*target_msym
, *func_msym
;
1266 target_msym
= lookup_minimal_symbol_by_pc (target_addr
).minsym
;
1267 func_msym
= lookup_minimal_symbol_by_pc (func_addr
).minsym
;
1268 throw_error (NO_ENTRY_VALUE_ERROR
,
1269 _("DW_OP_entry_value resolving expects callee %s at %s "
1270 "but the called frame is for %s at %s"),
1271 (target_msym
== NULL
? "???"
1272 : MSYMBOL_PRINT_NAME (target_msym
)),
1273 paddress (gdbarch
, target_addr
),
1274 func_msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (func_msym
),
1275 paddress (gdbarch
, func_addr
));
1278 /* No entry value based parameters would be reliable if this function can
1279 call itself via tail calls. */
1280 func_verify_no_selftailcall (gdbarch
, func_addr
);
1282 for (iparams
= 0; iparams
< call_site
->parameter_count
; iparams
++)
1284 parameter
= &call_site
->parameter
[iparams
];
1285 if (call_site_parameter_matches (parameter
, kind
, kind_u
))
1288 if (iparams
== call_site
->parameter_count
)
1290 struct minimal_symbol
*msym
1291 = lookup_minimal_symbol_by_pc (caller_pc
).minsym
;
1293 /* DW_TAG_call_site_parameter will be missing just if GCC could not
1294 determine its value. */
1295 throw_error (NO_ENTRY_VALUE_ERROR
, _("Cannot find matching parameter "
1296 "at DW_TAG_call_site %s at %s"),
1297 paddress (gdbarch
, caller_pc
),
1298 msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (msym
));
1301 *per_cu_return
= call_site
->per_cu
;
1305 /* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return
1306 the normal DW_AT_call_value block. Otherwise return the
1307 DW_AT_call_data_value (dereferenced) block.
1309 TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned
1312 Function always returns non-NULL, non-optimized out value. It throws
1313 NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */
1315 static struct value
*
1316 dwarf_entry_parameter_to_value (struct call_site_parameter
*parameter
,
1317 CORE_ADDR deref_size
, struct type
*type
,
1318 struct frame_info
*caller_frame
,
1319 struct dwarf2_per_cu_data
*per_cu
)
1321 const gdb_byte
*data_src
;
1325 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
1326 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
1328 /* DEREF_SIZE size is not verified here. */
1329 if (data_src
== NULL
)
1330 throw_error (NO_ENTRY_VALUE_ERROR
,
1331 _("Cannot resolve DW_AT_call_data_value"));
1333 /* DW_AT_call_value is a DWARF expression, not a DWARF
1334 location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from
1336 data
= (gdb_byte
*) alloca (size
+ 1);
1337 memcpy (data
, data_src
, size
);
1338 data
[size
] = DW_OP_stack_value
;
1340 return dwarf2_evaluate_loc_desc (type
, caller_frame
, data
, size
+ 1, per_cu
);
1343 /* VALUE must be of type lval_computed with entry_data_value_funcs. Perform
1344 the indirect method on it, that is use its stored target value, the sole
1345 purpose of entry_data_value_funcs.. */
1347 static struct value
*
1348 entry_data_value_coerce_ref (const struct value
*value
)
1350 struct type
*checked_type
= check_typedef (value_type (value
));
1351 struct value
*target_val
;
1353 if (!TYPE_IS_REFERENCE (checked_type
))
1356 target_val
= (struct value
*) value_computed_closure (value
);
1357 value_incref (target_val
);
1361 /* Implement copy_closure. */
1364 entry_data_value_copy_closure (const struct value
*v
)
1366 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1368 value_incref (target_val
);
1372 /* Implement free_closure. */
1375 entry_data_value_free_closure (struct value
*v
)
1377 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1379 value_free (target_val
);
1382 /* Vector for methods for an entry value reference where the referenced value
1383 is stored in the caller. On the first dereference use
1384 DW_AT_call_data_value in the caller. */
1386 static const struct lval_funcs entry_data_value_funcs
=
1390 NULL
, /* indirect */
1391 entry_data_value_coerce_ref
,
1392 NULL
, /* check_synthetic_pointer */
1393 entry_data_value_copy_closure
,
1394 entry_data_value_free_closure
1397 /* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U
1398 are used to match DW_AT_location at the caller's
1399 DW_TAG_call_site_parameter.
1401 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1402 cannot resolve the parameter for any reason. */
1404 static struct value
*
1405 value_of_dwarf_reg_entry (struct type
*type
, struct frame_info
*frame
,
1406 enum call_site_parameter_kind kind
,
1407 union call_site_parameter_u kind_u
)
1409 struct type
*checked_type
= check_typedef (type
);
1410 struct type
*target_type
= TYPE_TARGET_TYPE (checked_type
);
1411 struct frame_info
*caller_frame
= get_prev_frame (frame
);
1412 struct value
*outer_val
, *target_val
, *val
;
1413 struct call_site_parameter
*parameter
;
1414 struct dwarf2_per_cu_data
*caller_per_cu
;
1416 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
1419 outer_val
= dwarf_entry_parameter_to_value (parameter
, -1 /* deref_size */,
1423 /* Check if DW_AT_call_data_value cannot be used. If it should be
1424 used and it is not available do not fall back to OUTER_VAL - dereferencing
1425 TYPE_CODE_REF with non-entry data value would give current value - not the
1428 if (!TYPE_IS_REFERENCE (checked_type
)
1429 || TYPE_TARGET_TYPE (checked_type
) == NULL
)
1432 target_val
= dwarf_entry_parameter_to_value (parameter
,
1433 TYPE_LENGTH (target_type
),
1434 target_type
, caller_frame
,
1437 release_value (target_val
);
1438 val
= allocate_computed_value (type
, &entry_data_value_funcs
,
1439 target_val
/* closure */);
1441 /* Copy the referencing pointer to the new computed value. */
1442 memcpy (value_contents_raw (val
), value_contents_raw (outer_val
),
1443 TYPE_LENGTH (checked_type
));
1444 set_value_lazy (val
, 0);
1449 /* Read parameter of TYPE at (callee) FRAME's function entry. DATA and
1450 SIZE are DWARF block used to match DW_AT_location at the caller's
1451 DW_TAG_call_site_parameter.
1453 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1454 cannot resolve the parameter for any reason. */
1456 static struct value
*
1457 value_of_dwarf_block_entry (struct type
*type
, struct frame_info
*frame
,
1458 const gdb_byte
*block
, size_t block_len
)
1460 union call_site_parameter_u kind_u
;
1462 kind_u
.dwarf_reg
= dwarf_block_to_dwarf_reg (block
, block
+ block_len
);
1463 if (kind_u
.dwarf_reg
!= -1)
1464 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_DWARF_REG
,
1467 if (dwarf_block_to_fb_offset (block
, block
+ block_len
, &kind_u
.fb_offset
))
1468 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_FB_OFFSET
,
1471 /* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message
1472 suppressed during normal operation. The expression can be arbitrary if
1473 there is no caller-callee entry value binding expected. */
1474 throw_error (NO_ENTRY_VALUE_ERROR
,
1475 _("DWARF-2 expression error: DW_OP_entry_value is supported "
1476 "only for single DW_OP_reg* or for DW_OP_fbreg(*)"));
1479 struct piece_closure
1481 /* Reference count. */
1484 /* The CU from which this closure's expression came. */
1485 struct dwarf2_per_cu_data
*per_cu
= NULL
;
1487 /* The pieces describing this variable. */
1488 std::vector
<dwarf_expr_piece
> pieces
;
1490 /* Frame ID of frame to which a register value is relative, used
1491 only by DWARF_VALUE_REGISTER. */
1492 struct frame_id frame_id
;
1495 /* Allocate a closure for a value formed from separately-described
1498 static struct piece_closure
*
1499 allocate_piece_closure (struct dwarf2_per_cu_data
*per_cu
,
1500 std::vector
<dwarf_expr_piece
> &&pieces
,
1501 struct frame_info
*frame
)
1503 struct piece_closure
*c
= new piece_closure
;
1508 c
->pieces
= std::move (pieces
);
1510 c
->frame_id
= null_frame_id
;
1512 c
->frame_id
= get_frame_id (frame
);
1514 for (dwarf_expr_piece
&piece
: c
->pieces
)
1515 if (piece
.location
== DWARF_VALUE_STACK
)
1516 value_incref (piece
.v
.value
);
1521 /* Copy NBITS bits from SOURCE to DEST starting at the given bit
1522 offsets. Use the bit order as specified by BITS_BIG_ENDIAN.
1523 Source and destination buffers must not overlap. */
1526 copy_bitwise (gdb_byte
*dest
, ULONGEST dest_offset
,
1527 const gdb_byte
*source
, ULONGEST source_offset
,
1528 ULONGEST nbits
, int bits_big_endian
)
1530 unsigned int buf
, avail
;
1535 if (bits_big_endian
)
1537 /* Start from the end, then work backwards. */
1538 dest_offset
+= nbits
- 1;
1539 dest
+= dest_offset
/ 8;
1540 dest_offset
= 7 - dest_offset
% 8;
1541 source_offset
+= nbits
- 1;
1542 source
+= source_offset
/ 8;
1543 source_offset
= 7 - source_offset
% 8;
1547 dest
+= dest_offset
/ 8;
1549 source
+= source_offset
/ 8;
1553 /* Fill BUF with DEST_OFFSET bits from the destination and 8 -
1554 SOURCE_OFFSET bits from the source. */
1555 buf
= *(bits_big_endian
? source
-- : source
++) >> source_offset
;
1556 buf
<<= dest_offset
;
1557 buf
|= *dest
& ((1 << dest_offset
) - 1);
1559 /* NBITS: bits yet to be written; AVAIL: BUF's fill level. */
1560 nbits
+= dest_offset
;
1561 avail
= dest_offset
+ 8 - source_offset
;
1563 /* Flush 8 bits from BUF, if appropriate. */
1564 if (nbits
>= 8 && avail
>= 8)
1566 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1572 /* Copy the middle part. */
1575 size_t len
= nbits
/ 8;
1577 /* Use a faster method for byte-aligned copies. */
1580 if (bits_big_endian
)
1584 memcpy (dest
+ 1, source
+ 1, len
);
1588 memcpy (dest
, source
, len
);
1597 buf
|= *(bits_big_endian
? source
-- : source
++) << avail
;
1598 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1605 /* Write the last byte. */
1609 buf
|= *source
<< avail
;
1611 buf
&= (1 << nbits
) - 1;
1612 *dest
= (*dest
& (~0 << nbits
)) | buf
;
1618 namespace selftests
{
1620 /* Helper function for the unit test of copy_bitwise. Convert NBITS bits
1621 out of BITS, starting at OFFS, to the respective '0'/'1'-string. MSB0
1622 specifies whether to assume big endian bit numbering. Store the
1623 resulting (not null-terminated) string at STR. */
1626 bits_to_str (char *str
, const gdb_byte
*bits
, ULONGEST offs
,
1627 ULONGEST nbits
, int msb0
)
1632 for (i
= offs
/ 8, j
= offs
% 8; nbits
; i
++, j
= 0)
1634 unsigned int ch
= bits
[i
];
1635 for (; j
< 8 && nbits
; j
++, nbits
--)
1636 *str
++ = (ch
& (msb0
? (1 << (7 - j
)) : (1 << j
))) ? '1' : '0';
1640 /* Check one invocation of copy_bitwise with the given parameters. */
1643 check_copy_bitwise (const gdb_byte
*dest
, unsigned int dest_offset
,
1644 const gdb_byte
*source
, unsigned int source_offset
,
1645 unsigned int nbits
, int msb0
)
1647 size_t len
= align_up (dest_offset
+ nbits
, 8);
1648 char *expected
= (char *) alloca (len
+ 1);
1649 char *actual
= (char *) alloca (len
+ 1);
1650 gdb_byte
*buf
= (gdb_byte
*) alloca (len
/ 8);
1652 /* Compose a '0'/'1'-string that represents the expected result of
1654 Bits from [0, DEST_OFFSET) are filled from DEST.
1655 Bits from [DEST_OFFSET, DEST_OFFSET + NBITS) are filled from SOURCE.
1656 Bits from [DEST_OFFSET + NBITS, LEN) are filled from DEST.
1665 We should end up with:
1667 DDDDSSDD (D=dest, S=source)
1669 bits_to_str (expected
, dest
, 0, len
, msb0
);
1670 bits_to_str (expected
+ dest_offset
, source
, source_offset
, nbits
, msb0
);
1672 /* Fill BUF with data from DEST, apply copy_bitwise, and convert the
1673 result to a '0'/'1'-string. */
1674 memcpy (buf
, dest
, len
/ 8);
1675 copy_bitwise (buf
, dest_offset
, source
, source_offset
, nbits
, msb0
);
1676 bits_to_str (actual
, buf
, 0, len
, msb0
);
1678 /* Compare the resulting strings. */
1679 expected
[len
] = actual
[len
] = '\0';
1680 if (strcmp (expected
, actual
) != 0)
1681 error (_("copy_bitwise %s != %s (%u+%u -> %u)"),
1682 expected
, actual
, source_offset
, nbits
, dest_offset
);
1685 /* Unit test for copy_bitwise. */
1688 copy_bitwise_tests (void)
1690 /* Data to be used as both source and destination buffers. The two
1691 arrays below represent the lsb0- and msb0- encoded versions of the
1692 following bit string, respectively:
1693 00000000 00011111 11111111 01001000 10100101 11110010
1694 This pattern is chosen such that it contains:
1695 - constant 0- and 1- chunks of more than a full byte;
1696 - 0/1- and 1/0 transitions on all bit positions within a byte;
1697 - several sufficiently asymmetric bytes.
1699 static const gdb_byte data_lsb0
[] = {
1700 0x00, 0xf8, 0xff, 0x12, 0xa5, 0x4f
1702 static const gdb_byte data_msb0
[] = {
1703 0x00, 0x1f, 0xff, 0x48, 0xa5, 0xf2
1706 constexpr size_t data_nbits
= 8 * sizeof (data_lsb0
);
1707 constexpr unsigned max_nbits
= 24;
1709 /* Try all combinations of:
1710 lsb0/msb0 bit order (using the respective data array)
1711 X [0, MAX_NBITS] copy bit width
1712 X feasible source offsets for the given copy bit width
1713 X feasible destination offsets
1715 for (int msb0
= 0; msb0
< 2; msb0
++)
1717 const gdb_byte
*data
= msb0
? data_msb0
: data_lsb0
;
1719 for (unsigned int nbits
= 1; nbits
<= max_nbits
; nbits
++)
1721 const unsigned int max_offset
= data_nbits
- nbits
;
1723 for (unsigned source_offset
= 0;
1724 source_offset
<= max_offset
;
1727 for (unsigned dest_offset
= 0;
1728 dest_offset
<= max_offset
;
1731 check_copy_bitwise (data
+ dest_offset
/ 8,
1733 data
+ source_offset
/ 8,
1740 /* Special cases: copy all, copy nothing. */
1741 check_copy_bitwise (data_lsb0
, 0, data_msb0
, 0, data_nbits
, msb0
);
1742 check_copy_bitwise (data_msb0
, 0, data_lsb0
, 0, data_nbits
, msb0
);
1743 check_copy_bitwise (data
, data_nbits
- 7, data
, 9, 0, msb0
);
1747 } /* namespace selftests */
1749 #endif /* GDB_SELF_TEST */
1751 /* Return the number of bytes overlapping a contiguous chunk of N_BITS
1752 bits whose first bit is located at bit offset START. */
1755 bits_to_bytes (ULONGEST start
, ULONGEST n_bits
)
1757 return (start
% 8 + n_bits
+ 7) / 8;
1760 /* Read or write a pieced value V. If FROM != NULL, operate in "write
1761 mode": copy FROM into the pieces comprising V. If FROM == NULL,
1762 operate in "read mode": fetch the contents of the (lazy) value V by
1763 composing it from its pieces. */
1766 rw_pieced_value (struct value
*v
, struct value
*from
)
1769 LONGEST offset
= 0, max_offset
;
1770 ULONGEST bits_to_skip
;
1771 gdb_byte
*v_contents
;
1772 const gdb_byte
*from_contents
;
1773 struct piece_closure
*c
1774 = (struct piece_closure
*) value_computed_closure (v
);
1775 gdb::byte_vector buffer
;
1777 = gdbarch_bits_big_endian (get_type_arch (value_type (v
)));
1781 from_contents
= value_contents (from
);
1786 if (value_type (v
) != value_enclosing_type (v
))
1787 internal_error (__FILE__
, __LINE__
,
1788 _("Should not be able to create a lazy value with "
1789 "an enclosing type"));
1790 v_contents
= value_contents_raw (v
);
1791 from_contents
= NULL
;
1794 bits_to_skip
= 8 * value_offset (v
);
1795 if (value_bitsize (v
))
1797 bits_to_skip
+= (8 * value_offset (value_parent (v
))
1798 + value_bitpos (v
));
1800 && (gdbarch_byte_order (get_type_arch (value_type (from
)))
1803 /* Use the least significant bits of FROM. */
1804 max_offset
= 8 * TYPE_LENGTH (value_type (from
));
1805 offset
= max_offset
- value_bitsize (v
);
1808 max_offset
= value_bitsize (v
);
1811 max_offset
= 8 * TYPE_LENGTH (value_type (v
));
1813 /* Advance to the first non-skipped piece. */
1814 for (i
= 0; i
< c
->pieces
.size () && bits_to_skip
>= c
->pieces
[i
].size
; i
++)
1815 bits_to_skip
-= c
->pieces
[i
].size
;
1817 for (; i
< c
->pieces
.size () && offset
< max_offset
; i
++)
1819 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1820 size_t this_size_bits
, this_size
;
1822 this_size_bits
= p
->size
- bits_to_skip
;
1823 if (this_size_bits
> max_offset
- offset
)
1824 this_size_bits
= max_offset
- offset
;
1826 switch (p
->location
)
1828 case DWARF_VALUE_REGISTER
:
1830 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1831 struct gdbarch
*arch
= get_frame_arch (frame
);
1832 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1833 ULONGEST reg_bits
= 8 * register_size (arch
, gdb_regnum
);
1836 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1837 && p
->offset
+ p
->size
< reg_bits
)
1839 /* Big-endian, and we want less than full size. */
1840 bits_to_skip
+= reg_bits
- (p
->offset
+ p
->size
);
1843 bits_to_skip
+= p
->offset
;
1845 this_size
= bits_to_bytes (bits_to_skip
, this_size_bits
);
1846 buffer
.resize (this_size
);
1851 if (!get_frame_register_bytes (frame
, gdb_regnum
,
1853 this_size
, buffer
.data (),
1857 mark_value_bits_optimized_out (v
, offset
,
1860 mark_value_bits_unavailable (v
, offset
,
1865 copy_bitwise (v_contents
, offset
,
1866 buffer
.data (), bits_to_skip
% 8,
1867 this_size_bits
, bits_big_endian
);
1872 if (bits_to_skip
% 8 != 0 || this_size_bits
% 8 != 0)
1874 /* Data is copied non-byte-aligned into the register.
1875 Need some bits from original register value. */
1876 get_frame_register_bytes (frame
, gdb_regnum
,
1878 this_size
, buffer
.data (),
1881 throw_error (OPTIMIZED_OUT_ERROR
,
1882 _("Can't do read-modify-write to "
1883 "update bitfield; containing word "
1884 "has been optimized out"));
1886 throw_error (NOT_AVAILABLE_ERROR
,
1887 _("Can't do read-modify-write to "
1888 "update bitfield; containing word "
1892 copy_bitwise (buffer
.data (), bits_to_skip
% 8,
1893 from_contents
, offset
,
1894 this_size_bits
, bits_big_endian
);
1895 put_frame_register_bytes (frame
, gdb_regnum
,
1897 this_size
, buffer
.data ());
1902 case DWARF_VALUE_MEMORY
:
1904 bits_to_skip
+= p
->offset
;
1906 CORE_ADDR start_addr
= p
->v
.mem
.addr
+ bits_to_skip
/ 8;
1908 if (bits_to_skip
% 8 == 0 && this_size_bits
% 8 == 0
1911 /* Everything is byte-aligned; no buffer needed. */
1913 write_memory_with_notification (start_addr
,
1916 this_size_bits
/ 8);
1918 read_value_memory (v
, offset
,
1919 p
->v
.mem
.in_stack_memory
,
1920 p
->v
.mem
.addr
+ bits_to_skip
/ 8,
1921 v_contents
+ offset
/ 8,
1922 this_size_bits
/ 8);
1926 this_size
= bits_to_bytes (bits_to_skip
, this_size_bits
);
1927 buffer
.resize (this_size
);
1932 read_value_memory (v
, offset
,
1933 p
->v
.mem
.in_stack_memory
,
1934 p
->v
.mem
.addr
+ bits_to_skip
/ 8,
1935 buffer
.data (), this_size
);
1936 copy_bitwise (v_contents
, offset
,
1937 buffer
.data (), bits_to_skip
% 8,
1938 this_size_bits
, bits_big_endian
);
1943 if (bits_to_skip
% 8 != 0 || this_size_bits
% 8 != 0)
1947 /* Perform a single read for small sizes. */
1948 read_memory (start_addr
, buffer
.data (),
1953 /* Only the first and last bytes can possibly have
1955 read_memory (start_addr
, buffer
.data (), 1);
1956 read_memory (start_addr
+ this_size
- 1,
1957 &buffer
[this_size
- 1], 1);
1961 copy_bitwise (buffer
.data (), bits_to_skip
% 8,
1962 from_contents
, offset
,
1963 this_size_bits
, bits_big_endian
);
1964 write_memory_with_notification (start_addr
,
1971 case DWARF_VALUE_STACK
:
1975 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1979 struct objfile
*objfile
= dwarf2_per_cu_objfile (c
->per_cu
);
1980 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
1981 ULONGEST stack_value_size_bits
1982 = 8 * TYPE_LENGTH (value_type (p
->v
.value
));
1984 /* Use zeroes if piece reaches beyond stack value. */
1985 if (p
->offset
+ p
->size
> stack_value_size_bits
)
1988 /* Piece is anchored at least significant bit end. */
1989 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
1990 bits_to_skip
+= stack_value_size_bits
- p
->offset
- p
->size
;
1992 bits_to_skip
+= p
->offset
;
1994 copy_bitwise (v_contents
, offset
,
1995 value_contents_all (p
->v
.value
),
1997 this_size_bits
, bits_big_endian
);
2001 case DWARF_VALUE_LITERAL
:
2005 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
2009 ULONGEST literal_size_bits
= 8 * p
->v
.literal
.length
;
2010 size_t n
= this_size_bits
;
2012 /* Cut off at the end of the implicit value. */
2013 bits_to_skip
+= p
->offset
;
2014 if (bits_to_skip
>= literal_size_bits
)
2016 if (n
> literal_size_bits
- bits_to_skip
)
2017 n
= literal_size_bits
- bits_to_skip
;
2019 copy_bitwise (v_contents
, offset
,
2020 p
->v
.literal
.data
, bits_to_skip
,
2021 n
, bits_big_endian
);
2025 case DWARF_VALUE_IMPLICIT_POINTER
:
2028 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
2032 /* These bits show up as zeros -- but do not cause the value to
2033 be considered optimized-out. */
2036 case DWARF_VALUE_OPTIMIZED_OUT
:
2037 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
2041 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2044 offset
+= this_size_bits
;
2051 read_pieced_value (struct value
*v
)
2053 rw_pieced_value (v
, NULL
);
2057 write_pieced_value (struct value
*to
, struct value
*from
)
2059 rw_pieced_value (to
, from
);
2062 /* An implementation of an lval_funcs method to see whether a value is
2063 a synthetic pointer. */
2066 check_pieced_synthetic_pointer (const struct value
*value
, LONGEST bit_offset
,
2069 struct piece_closure
*c
2070 = (struct piece_closure
*) value_computed_closure (value
);
2073 bit_offset
+= 8 * value_offset (value
);
2074 if (value_bitsize (value
))
2075 bit_offset
+= value_bitpos (value
);
2077 for (i
= 0; i
< c
->pieces
.size () && bit_length
> 0; i
++)
2079 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2080 size_t this_size_bits
= p
->size
;
2084 if (bit_offset
>= this_size_bits
)
2086 bit_offset
-= this_size_bits
;
2090 bit_length
-= this_size_bits
- bit_offset
;
2094 bit_length
-= this_size_bits
;
2096 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2103 /* A wrapper function for get_frame_address_in_block. */
2106 get_frame_address_in_block_wrapper (void *baton
)
2108 return get_frame_address_in_block ((struct frame_info
*) baton
);
2111 /* Fetch a DW_AT_const_value through a synthetic pointer. */
2113 static struct value
*
2114 fetch_const_value_from_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2115 struct dwarf2_per_cu_data
*per_cu
,
2118 struct value
*result
= NULL
;
2119 const gdb_byte
*bytes
;
2122 auto_obstack temp_obstack
;
2123 bytes
= dwarf2_fetch_constant_bytes (die
, per_cu
, &temp_obstack
, &len
);
2127 if (byte_offset
>= 0
2128 && byte_offset
+ TYPE_LENGTH (TYPE_TARGET_TYPE (type
)) <= len
)
2130 bytes
+= byte_offset
;
2131 result
= value_from_contents (TYPE_TARGET_TYPE (type
), bytes
);
2134 invalid_synthetic_pointer ();
2137 result
= allocate_optimized_out_value (TYPE_TARGET_TYPE (type
));
2142 /* Fetch the value pointed to by a synthetic pointer. */
2144 static struct value
*
2145 indirect_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2146 struct dwarf2_per_cu_data
*per_cu
,
2147 struct frame_info
*frame
, struct type
*type
)
2149 /* Fetch the location expression of the DIE we're pointing to. */
2150 struct dwarf2_locexpr_baton baton
2151 = dwarf2_fetch_die_loc_sect_off (die
, per_cu
,
2152 get_frame_address_in_block_wrapper
, frame
);
2154 /* Get type of pointed-to DIE. */
2155 struct type
*orig_type
= dwarf2_fetch_die_type_sect_off (die
, per_cu
);
2156 if (orig_type
== NULL
)
2157 invalid_synthetic_pointer ();
2159 /* If pointed-to DIE has a DW_AT_location, evaluate it and return the
2160 resulting value. Otherwise, it may have a DW_AT_const_value instead,
2161 or it may've been optimized out. */
2162 if (baton
.data
!= NULL
)
2163 return dwarf2_evaluate_loc_desc_full (orig_type
, frame
, baton
.data
,
2164 baton
.size
, baton
.per_cu
,
2165 TYPE_TARGET_TYPE (type
),
2168 return fetch_const_value_from_synthetic_pointer (die
, byte_offset
, per_cu
,
2172 /* An implementation of an lval_funcs method to indirect through a
2173 pointer. This handles the synthetic pointer case when needed. */
2175 static struct value
*
2176 indirect_pieced_value (struct value
*value
)
2178 struct piece_closure
*c
2179 = (struct piece_closure
*) value_computed_closure (value
);
2181 struct frame_info
*frame
;
2182 struct dwarf2_locexpr_baton baton
;
2185 struct dwarf_expr_piece
*piece
= NULL
;
2186 LONGEST byte_offset
;
2187 enum bfd_endian byte_order
;
2189 type
= check_typedef (value_type (value
));
2190 if (TYPE_CODE (type
) != TYPE_CODE_PTR
)
2193 bit_length
= 8 * TYPE_LENGTH (type
);
2194 bit_offset
= 8 * value_offset (value
);
2195 if (value_bitsize (value
))
2196 bit_offset
+= value_bitpos (value
);
2198 for (i
= 0; i
< c
->pieces
.size () && bit_length
> 0; i
++)
2200 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2201 size_t this_size_bits
= p
->size
;
2205 if (bit_offset
>= this_size_bits
)
2207 bit_offset
-= this_size_bits
;
2211 bit_length
-= this_size_bits
- bit_offset
;
2215 bit_length
-= this_size_bits
;
2217 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2220 if (bit_length
!= 0)
2221 error (_("Invalid use of DW_OP_implicit_pointer"));
2227 gdb_assert (piece
!= NULL
);
2228 frame
= get_selected_frame (_("No frame selected."));
2230 /* This is an offset requested by GDB, such as value subscripts.
2231 However, due to how synthetic pointers are implemented, this is
2232 always presented to us as a pointer type. This means we have to
2233 sign-extend it manually as appropriate. Use raw
2234 extract_signed_integer directly rather than value_as_address and
2235 sign extend afterwards on architectures that would need it
2236 (mostly everywhere except MIPS, which has signed addresses) as
2237 the later would go through gdbarch_pointer_to_address and thus
2238 return a CORE_ADDR with high bits set on architectures that
2239 encode address spaces and other things in CORE_ADDR. */
2240 byte_order
= gdbarch_byte_order (get_frame_arch (frame
));
2241 byte_offset
= extract_signed_integer (value_contents (value
),
2242 TYPE_LENGTH (type
), byte_order
);
2243 byte_offset
+= piece
->v
.ptr
.offset
;
2245 return indirect_synthetic_pointer (piece
->v
.ptr
.die_sect_off
,
2246 byte_offset
, c
->per_cu
,
2250 /* Implementation of the coerce_ref method of lval_funcs for synthetic C++
2253 static struct value
*
2254 coerce_pieced_ref (const struct value
*value
)
2256 struct type
*type
= check_typedef (value_type (value
));
2258 if (value_bits_synthetic_pointer (value
, value_embedded_offset (value
),
2259 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
2261 const struct piece_closure
*closure
2262 = (struct piece_closure
*) value_computed_closure (value
);
2263 struct frame_info
*frame
2264 = get_selected_frame (_("No frame selected."));
2266 /* gdb represents synthetic pointers as pieced values with a single
2268 gdb_assert (closure
!= NULL
);
2269 gdb_assert (closure
->pieces
.size () == 1);
2271 return indirect_synthetic_pointer
2272 (closure
->pieces
[0].v
.ptr
.die_sect_off
,
2273 closure
->pieces
[0].v
.ptr
.offset
,
2274 closure
->per_cu
, frame
, type
);
2278 /* Else: not a synthetic reference; do nothing. */
2284 copy_pieced_value_closure (const struct value
*v
)
2286 struct piece_closure
*c
2287 = (struct piece_closure
*) value_computed_closure (v
);
2294 free_pieced_value_closure (struct value
*v
)
2296 struct piece_closure
*c
2297 = (struct piece_closure
*) value_computed_closure (v
);
2302 for (dwarf_expr_piece
&p
: c
->pieces
)
2303 if (p
.location
== DWARF_VALUE_STACK
)
2304 value_free (p
.v
.value
);
2310 /* Functions for accessing a variable described by DW_OP_piece. */
2311 static const struct lval_funcs pieced_value_funcs
= {
2314 indirect_pieced_value
,
2316 check_pieced_synthetic_pointer
,
2317 copy_pieced_value_closure
,
2318 free_pieced_value_closure
2321 /* Evaluate a location description, starting at DATA and with length
2322 SIZE, to find the current location of variable of TYPE in the
2323 context of FRAME. If SUBOBJ_TYPE is non-NULL, return instead the
2324 location of the subobject of type SUBOBJ_TYPE at byte offset
2325 SUBOBJ_BYTE_OFFSET within the variable of type TYPE. */
2327 static struct value
*
2328 dwarf2_evaluate_loc_desc_full (struct type
*type
, struct frame_info
*frame
,
2329 const gdb_byte
*data
, size_t size
,
2330 struct dwarf2_per_cu_data
*per_cu
,
2331 struct type
*subobj_type
,
2332 LONGEST subobj_byte_offset
)
2334 struct value
*retval
;
2335 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2337 if (subobj_type
== NULL
)
2340 subobj_byte_offset
= 0;
2342 else if (subobj_byte_offset
< 0)
2343 invalid_synthetic_pointer ();
2346 return allocate_optimized_out_value (subobj_type
);
2348 dwarf_evaluate_loc_desc ctx
;
2350 ctx
.per_cu
= per_cu
;
2351 ctx
.obj_address
= 0;
2353 scoped_value_mark free_values
;
2355 ctx
.gdbarch
= get_objfile_arch (objfile
);
2356 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2357 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2358 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2362 ctx
.eval (data
, size
);
2364 CATCH (ex
, RETURN_MASK_ERROR
)
2366 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2368 free_values
.free_to_mark ();
2369 retval
= allocate_value (subobj_type
);
2370 mark_value_bytes_unavailable (retval
, 0,
2371 TYPE_LENGTH (subobj_type
));
2374 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2376 if (entry_values_debug
)
2377 exception_print (gdb_stdout
, ex
);
2378 free_values
.free_to_mark ();
2379 return allocate_optimized_out_value (subobj_type
);
2382 throw_exception (ex
);
2386 if (ctx
.pieces
.size () > 0)
2388 struct piece_closure
*c
;
2389 ULONGEST bit_size
= 0;
2392 for (dwarf_expr_piece
&piece
: ctx
.pieces
)
2393 bit_size
+= piece
.size
;
2394 /* Complain if the expression is larger than the size of the
2396 if (bit_size
> 8 * TYPE_LENGTH (type
))
2397 invalid_synthetic_pointer ();
2399 c
= allocate_piece_closure (per_cu
, std::move (ctx
.pieces
), frame
);
2400 /* We must clean up the value chain after creating the piece
2401 closure but before allocating the result. */
2402 free_values
.free_to_mark ();
2403 retval
= allocate_computed_value (subobj_type
,
2404 &pieced_value_funcs
, c
);
2405 set_value_offset (retval
, subobj_byte_offset
);
2409 switch (ctx
.location
)
2411 case DWARF_VALUE_REGISTER
:
2413 struct gdbarch
*arch
= get_frame_arch (frame
);
2415 = longest_to_int (value_as_long (ctx
.fetch (0)));
2416 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, dwarf_regnum
);
2418 if (subobj_byte_offset
!= 0)
2419 error (_("cannot use offset on synthetic pointer to register"));
2420 free_values
.free_to_mark ();
2421 retval
= value_from_register (subobj_type
, gdb_regnum
, frame
);
2422 if (value_optimized_out (retval
))
2426 /* This means the register has undefined value / was
2427 not saved. As we're computing the location of some
2428 variable etc. in the program, not a value for
2429 inspecting a register ($pc, $sp, etc.), return a
2430 generic optimized out value instead, so that we show
2431 <optimized out> instead of <not saved>. */
2432 tmp
= allocate_value (subobj_type
);
2433 value_contents_copy (tmp
, 0, retval
, 0,
2434 TYPE_LENGTH (subobj_type
));
2440 case DWARF_VALUE_MEMORY
:
2442 struct type
*ptr_type
;
2443 CORE_ADDR address
= ctx
.fetch_address (0);
2444 bool in_stack_memory
= ctx
.fetch_in_stack_memory (0);
2446 /* DW_OP_deref_size (and possibly other operations too) may
2447 create a pointer instead of an address. Ideally, the
2448 pointer to address conversion would be performed as part
2449 of those operations, but the type of the object to
2450 which the address refers is not known at the time of
2451 the operation. Therefore, we do the conversion here
2452 since the type is readily available. */
2454 switch (TYPE_CODE (subobj_type
))
2456 case TYPE_CODE_FUNC
:
2457 case TYPE_CODE_METHOD
:
2458 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_func_ptr
;
2461 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_data_ptr
;
2464 address
= value_as_address (value_from_pointer (ptr_type
, address
));
2466 free_values
.free_to_mark ();
2467 retval
= value_at_lazy (subobj_type
,
2468 address
+ subobj_byte_offset
);
2469 if (in_stack_memory
)
2470 set_value_stack (retval
, 1);
2474 case DWARF_VALUE_STACK
:
2476 struct value
*value
= ctx
.fetch (0);
2477 size_t n
= TYPE_LENGTH (value_type (value
));
2478 size_t len
= TYPE_LENGTH (subobj_type
);
2479 size_t max
= TYPE_LENGTH (type
);
2480 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2482 if (subobj_byte_offset
+ len
> max
)
2483 invalid_synthetic_pointer ();
2485 /* Preserve VALUE because we are going to free values back
2486 to the mark, but we still need the value contents
2488 value_incref (value
);
2489 free_values
.free_to_mark ();
2490 gdb_value_up
value_holder (value
);
2492 retval
= allocate_value (subobj_type
);
2494 /* The given offset is relative to the actual object. */
2495 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2496 subobj_byte_offset
+= n
- max
;
2498 memcpy (value_contents_raw (retval
),
2499 value_contents_all (value
) + subobj_byte_offset
, len
);
2503 case DWARF_VALUE_LITERAL
:
2506 size_t n
= TYPE_LENGTH (subobj_type
);
2508 if (subobj_byte_offset
+ n
> ctx
.len
)
2509 invalid_synthetic_pointer ();
2511 free_values
.free_to_mark ();
2512 retval
= allocate_value (subobj_type
);
2513 contents
= value_contents_raw (retval
);
2514 memcpy (contents
, ctx
.data
+ subobj_byte_offset
, n
);
2518 case DWARF_VALUE_OPTIMIZED_OUT
:
2519 free_values
.free_to_mark ();
2520 retval
= allocate_optimized_out_value (subobj_type
);
2523 /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
2524 operation by execute_stack_op. */
2525 case DWARF_VALUE_IMPLICIT_POINTER
:
2526 /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
2527 it can only be encountered when making a piece. */
2529 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2533 set_value_initialized (retval
, ctx
.initialized
);
2538 /* The exported interface to dwarf2_evaluate_loc_desc_full; it always
2539 passes 0 as the byte_offset. */
2542 dwarf2_evaluate_loc_desc (struct type
*type
, struct frame_info
*frame
,
2543 const gdb_byte
*data
, size_t size
,
2544 struct dwarf2_per_cu_data
*per_cu
)
2546 return dwarf2_evaluate_loc_desc_full (type
, frame
, data
, size
, per_cu
,
2550 /* Evaluates a dwarf expression and stores the result in VAL, expecting
2551 that the dwarf expression only produces a single CORE_ADDR. FRAME is the
2552 frame in which the expression is evaluated. ADDR is a context (location of
2553 a variable) and might be needed to evaluate the location expression.
2554 Returns 1 on success, 0 otherwise. */
2557 dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton
*dlbaton
,
2558 struct frame_info
*frame
,
2562 struct objfile
*objfile
;
2564 if (dlbaton
== NULL
|| dlbaton
->size
== 0)
2567 dwarf_evaluate_loc_desc ctx
;
2570 ctx
.per_cu
= dlbaton
->per_cu
;
2571 ctx
.obj_address
= addr
;
2573 objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
2575 ctx
.gdbarch
= get_objfile_arch (objfile
);
2576 ctx
.addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
2577 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (dlbaton
->per_cu
);
2578 ctx
.offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
2580 ctx
.eval (dlbaton
->data
, dlbaton
->size
);
2582 switch (ctx
.location
)
2584 case DWARF_VALUE_REGISTER
:
2585 case DWARF_VALUE_MEMORY
:
2586 case DWARF_VALUE_STACK
:
2587 *valp
= ctx
.fetch_address (0);
2588 if (ctx
.location
== DWARF_VALUE_REGISTER
)
2589 *valp
= ctx
.read_addr_from_reg (*valp
);
2591 case DWARF_VALUE_LITERAL
:
2592 *valp
= extract_signed_integer (ctx
.data
, ctx
.len
,
2593 gdbarch_byte_order (ctx
.gdbarch
));
2595 /* Unsupported dwarf values. */
2596 case DWARF_VALUE_OPTIMIZED_OUT
:
2597 case DWARF_VALUE_IMPLICIT_POINTER
:
2604 /* See dwarf2loc.h. */
2607 dwarf2_evaluate_property (const struct dynamic_prop
*prop
,
2608 struct frame_info
*frame
,
2609 struct property_addr_info
*addr_stack
,
2615 if (frame
== NULL
&& has_stack_frames ())
2616 frame
= get_selected_frame (NULL
);
2622 const struct dwarf2_property_baton
*baton
2623 = (const struct dwarf2_property_baton
*) prop
->data
.baton
;
2625 if (dwarf2_locexpr_baton_eval (&baton
->locexpr
, frame
,
2626 addr_stack
? addr_stack
->addr
: 0,
2629 if (baton
->referenced_type
)
2631 struct value
*val
= value_at (baton
->referenced_type
, *value
);
2633 *value
= value_as_address (val
);
2642 struct dwarf2_property_baton
*baton
2643 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2644 CORE_ADDR pc
= get_frame_address_in_block (frame
);
2645 const gdb_byte
*data
;
2649 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2652 val
= dwarf2_evaluate_loc_desc (baton
->referenced_type
, frame
, data
,
2653 size
, baton
->loclist
.per_cu
);
2654 if (!value_optimized_out (val
))
2656 *value
= value_as_address (val
);
2664 *value
= prop
->data
.const_val
;
2667 case PROP_ADDR_OFFSET
:
2669 struct dwarf2_property_baton
*baton
2670 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2671 struct property_addr_info
*pinfo
;
2674 for (pinfo
= addr_stack
; pinfo
!= NULL
; pinfo
= pinfo
->next
)
2675 if (pinfo
->type
== baton
->referenced_type
)
2678 error (_("cannot find reference address for offset property"));
2679 if (pinfo
->valaddr
!= NULL
)
2680 val
= value_from_contents
2681 (baton
->offset_info
.type
,
2682 pinfo
->valaddr
+ baton
->offset_info
.offset
);
2684 val
= value_at (baton
->offset_info
.type
,
2685 pinfo
->addr
+ baton
->offset_info
.offset
);
2686 *value
= value_as_address (val
);
2694 /* See dwarf2loc.h. */
2697 dwarf2_compile_property_to_c (string_file
&stream
,
2698 const char *result_name
,
2699 struct gdbarch
*gdbarch
,
2700 unsigned char *registers_used
,
2701 const struct dynamic_prop
*prop
,
2705 struct dwarf2_property_baton
*baton
2706 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2707 const gdb_byte
*data
;
2709 struct dwarf2_per_cu_data
*per_cu
;
2711 if (prop
->kind
== PROP_LOCEXPR
)
2713 data
= baton
->locexpr
.data
;
2714 size
= baton
->locexpr
.size
;
2715 per_cu
= baton
->locexpr
.per_cu
;
2719 gdb_assert (prop
->kind
== PROP_LOCLIST
);
2721 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2722 per_cu
= baton
->loclist
.per_cu
;
2725 compile_dwarf_bounds_to_c (stream
, result_name
, prop
, sym
, pc
,
2726 gdbarch
, registers_used
,
2727 dwarf2_per_cu_addr_size (per_cu
),
2728 data
, data
+ size
, per_cu
);
2732 /* Helper functions and baton for dwarf2_loc_desc_get_symbol_read_needs. */
2734 class symbol_needs_eval_context
: public dwarf_expr_context
2738 enum symbol_needs_kind needs
;
2739 struct dwarf2_per_cu_data
*per_cu
;
2741 /* Reads from registers do require a frame. */
2742 CORE_ADDR
read_addr_from_reg (int regnum
) OVERRIDE
2744 needs
= SYMBOL_NEEDS_FRAME
;
2748 /* "get_reg_value" callback: Reads from registers do require a
2751 struct value
*get_reg_value (struct type
*type
, int regnum
) OVERRIDE
2753 needs
= SYMBOL_NEEDS_FRAME
;
2754 return value_zero (type
, not_lval
);
2757 /* Reads from memory do not require a frame. */
2758 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
2760 memset (buf
, 0, len
);
2763 /* Frame-relative accesses do require a frame. */
2764 void get_frame_base (const gdb_byte
**start
, size_t *length
) OVERRIDE
2766 static gdb_byte lit0
= DW_OP_lit0
;
2771 needs
= SYMBOL_NEEDS_FRAME
;
2774 /* CFA accesses require a frame. */
2775 CORE_ADDR
get_frame_cfa () OVERRIDE
2777 needs
= SYMBOL_NEEDS_FRAME
;
2781 CORE_ADDR
get_frame_pc () OVERRIDE
2783 needs
= SYMBOL_NEEDS_FRAME
;
2787 /* Thread-local accesses require registers, but not a frame. */
2788 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
2790 if (needs
<= SYMBOL_NEEDS_REGISTERS
)
2791 needs
= SYMBOL_NEEDS_REGISTERS
;
2795 /* Helper interface of per_cu_dwarf_call for
2796 dwarf2_loc_desc_get_symbol_read_needs. */
2798 void dwarf_call (cu_offset die_offset
) OVERRIDE
2800 per_cu_dwarf_call (this, die_offset
, per_cu
);
2803 /* DW_OP_entry_value accesses require a caller, therefore a
2806 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
2807 union call_site_parameter_u kind_u
,
2808 int deref_size
) OVERRIDE
2810 needs
= SYMBOL_NEEDS_FRAME
;
2812 /* The expression may require some stub values on DWARF stack. */
2813 push_address (0, 0);
2816 /* DW_OP_GNU_addr_index doesn't require a frame. */
2818 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
2820 /* Nothing to do. */
2824 /* DW_OP_push_object_address has a frame already passed through. */
2826 CORE_ADDR
get_object_address () OVERRIDE
2828 /* Nothing to do. */
2833 /* Compute the correct symbol_needs_kind value for the location
2834 expression at DATA (length SIZE). */
2836 static enum symbol_needs_kind
2837 dwarf2_loc_desc_get_symbol_read_needs (const gdb_byte
*data
, size_t size
,
2838 struct dwarf2_per_cu_data
*per_cu
)
2841 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2843 scoped_value_mark free_values
;
2845 symbol_needs_eval_context ctx
;
2847 ctx
.needs
= SYMBOL_NEEDS_NONE
;
2848 ctx
.per_cu
= per_cu
;
2849 ctx
.gdbarch
= get_objfile_arch (objfile
);
2850 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2851 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2852 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2854 ctx
.eval (data
, size
);
2856 in_reg
= ctx
.location
== DWARF_VALUE_REGISTER
;
2858 /* If the location has several pieces, and any of them are in
2859 registers, then we will need a frame to fetch them from. */
2860 for (dwarf_expr_piece
&p
: ctx
.pieces
)
2861 if (p
.location
== DWARF_VALUE_REGISTER
)
2865 ctx
.needs
= SYMBOL_NEEDS_FRAME
;
2869 /* A helper function that throws an unimplemented error mentioning a
2870 given DWARF operator. */
2873 unimplemented (unsigned int op
)
2875 const char *name
= get_DW_OP_name (op
);
2878 error (_("DWARF operator %s cannot be translated to an agent expression"),
2881 error (_("Unknown DWARF operator 0x%02x cannot be translated "
2882 "to an agent expression"),
2888 This is basically a wrapper on gdbarch_dwarf2_reg_to_regnum so that we
2889 can issue a complaint, which is better than having every target's
2890 implementation of dwarf2_reg_to_regnum do it. */
2893 dwarf_reg_to_regnum (struct gdbarch
*arch
, int dwarf_reg
)
2895 int reg
= gdbarch_dwarf2_reg_to_regnum (arch
, dwarf_reg
);
2899 complaint (&symfile_complaints
,
2900 _("bad DWARF register number %d"), dwarf_reg
);
2905 /* Subroutine of dwarf_reg_to_regnum_or_error to simplify it.
2906 Throw an error because DWARF_REG is bad. */
2909 throw_bad_regnum_error (ULONGEST dwarf_reg
)
2911 /* Still want to print -1 as "-1".
2912 We *could* have int and ULONGEST versions of dwarf2_reg_to_regnum_or_error
2913 but that's overkill for now. */
2914 if ((int) dwarf_reg
== dwarf_reg
)
2915 error (_("Unable to access DWARF register number %d"), (int) dwarf_reg
);
2916 error (_("Unable to access DWARF register number %s"),
2917 pulongest (dwarf_reg
));
2920 /* See dwarf2loc.h. */
2923 dwarf_reg_to_regnum_or_error (struct gdbarch
*arch
, ULONGEST dwarf_reg
)
2927 if (dwarf_reg
> INT_MAX
)
2928 throw_bad_regnum_error (dwarf_reg
);
2929 /* Yes, we will end up issuing a complaint and an error if DWARF_REG is
2930 bad, but that's ok. */
2931 reg
= dwarf_reg_to_regnum (arch
, (int) dwarf_reg
);
2933 throw_bad_regnum_error (dwarf_reg
);
2937 /* A helper function that emits an access to memory. ARCH is the
2938 target architecture. EXPR is the expression which we are building.
2939 NBITS is the number of bits we want to read. This emits the
2940 opcodes needed to read the memory and then extract the desired
2944 access_memory (struct gdbarch
*arch
, struct agent_expr
*expr
, ULONGEST nbits
)
2946 ULONGEST nbytes
= (nbits
+ 7) / 8;
2948 gdb_assert (nbytes
> 0 && nbytes
<= sizeof (LONGEST
));
2951 ax_trace_quick (expr
, nbytes
);
2954 ax_simple (expr
, aop_ref8
);
2955 else if (nbits
<= 16)
2956 ax_simple (expr
, aop_ref16
);
2957 else if (nbits
<= 32)
2958 ax_simple (expr
, aop_ref32
);
2960 ax_simple (expr
, aop_ref64
);
2962 /* If we read exactly the number of bytes we wanted, we're done. */
2963 if (8 * nbytes
== nbits
)
2966 if (gdbarch_bits_big_endian (arch
))
2968 /* On a bits-big-endian machine, we want the high-order
2970 ax_const_l (expr
, 8 * nbytes
- nbits
);
2971 ax_simple (expr
, aop_rsh_unsigned
);
2975 /* On a bits-little-endian box, we want the low-order NBITS. */
2976 ax_zero_ext (expr
, nbits
);
2980 /* A helper function to return the frame's PC. */
2983 get_ax_pc (void *baton
)
2985 struct agent_expr
*expr
= (struct agent_expr
*) baton
;
2990 /* Compile a DWARF location expression to an agent expression.
2992 EXPR is the agent expression we are building.
2993 LOC is the agent value we modify.
2994 ARCH is the architecture.
2995 ADDR_SIZE is the size of addresses, in bytes.
2996 OP_PTR is the start of the location expression.
2997 OP_END is one past the last byte of the location expression.
2999 This will throw an exception for various kinds of errors -- for
3000 example, if the expression cannot be compiled, or if the expression
3004 dwarf2_compile_expr_to_ax (struct agent_expr
*expr
, struct axs_value
*loc
,
3005 unsigned int addr_size
, const gdb_byte
*op_ptr
,
3006 const gdb_byte
*op_end
,
3007 struct dwarf2_per_cu_data
*per_cu
)
3009 gdbarch
*arch
= expr
->gdbarch
;
3011 std::vector
<int> dw_labels
, patches
;
3012 const gdb_byte
* const base
= op_ptr
;
3013 const gdb_byte
*previous_piece
= op_ptr
;
3014 enum bfd_endian byte_order
= gdbarch_byte_order (arch
);
3015 ULONGEST bits_collected
= 0;
3016 unsigned int addr_size_bits
= 8 * addr_size
;
3017 int bits_big_endian
= gdbarch_bits_big_endian (arch
);
3019 std::vector
<int> offsets (op_end
- op_ptr
, -1);
3021 /* By default we are making an address. */
3022 loc
->kind
= axs_lvalue_memory
;
3024 while (op_ptr
< op_end
)
3026 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *op_ptr
;
3027 uint64_t uoffset
, reg
;
3031 offsets
[op_ptr
- base
] = expr
->len
;
3034 /* Our basic approach to code generation is to map DWARF
3035 operations directly to AX operations. However, there are
3038 First, DWARF works on address-sized units, but AX always uses
3039 LONGEST. For most operations we simply ignore this
3040 difference; instead we generate sign extensions as needed
3041 before division and comparison operations. It would be nice
3042 to omit the sign extensions, but there is no way to determine
3043 the size of the target's LONGEST. (This code uses the size
3044 of the host LONGEST in some cases -- that is a bug but it is
3047 Second, some DWARF operations cannot be translated to AX.
3048 For these we simply fail. See
3049 http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
3084 ax_const_l (expr
, op
- DW_OP_lit0
);
3088 uoffset
= extract_unsigned_integer (op_ptr
, addr_size
, byte_order
);
3089 op_ptr
+= addr_size
;
3090 /* Some versions of GCC emit DW_OP_addr before
3091 DW_OP_GNU_push_tls_address. In this case the value is an
3092 index, not an address. We don't support things like
3093 branching between the address and the TLS op. */
3094 if (op_ptr
>= op_end
|| *op_ptr
!= DW_OP_GNU_push_tls_address
)
3095 uoffset
+= dwarf2_per_cu_text_offset (per_cu
);
3096 ax_const_l (expr
, uoffset
);
3100 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 1, byte_order
));
3104 ax_const_l (expr
, extract_signed_integer (op_ptr
, 1, byte_order
));
3108 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 2, byte_order
));
3112 ax_const_l (expr
, extract_signed_integer (op_ptr
, 2, byte_order
));
3116 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 4, byte_order
));
3120 ax_const_l (expr
, extract_signed_integer (op_ptr
, 4, byte_order
));
3124 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 8, byte_order
));
3128 ax_const_l (expr
, extract_signed_integer (op_ptr
, 8, byte_order
));
3132 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3133 ax_const_l (expr
, uoffset
);
3136 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3137 ax_const_l (expr
, offset
);
3172 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3173 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_reg0
);
3174 loc
->kind
= axs_lvalue_register
;
3178 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3179 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3180 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3181 loc
->kind
= axs_lvalue_register
;
3184 case DW_OP_implicit_value
:
3188 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &len
);
3189 if (op_ptr
+ len
> op_end
)
3190 error (_("DW_OP_implicit_value: too few bytes available."));
3191 if (len
> sizeof (ULONGEST
))
3192 error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
3195 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, len
,
3198 dwarf_expr_require_composition (op_ptr
, op_end
,
3199 "DW_OP_implicit_value");
3201 loc
->kind
= axs_rvalue
;
3205 case DW_OP_stack_value
:
3206 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_stack_value");
3207 loc
->kind
= axs_rvalue
;
3242 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3243 i
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_breg0
);
3247 ax_const_l (expr
, offset
);
3248 ax_simple (expr
, aop_add
);
3253 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3254 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3255 i
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3259 ax_const_l (expr
, offset
);
3260 ax_simple (expr
, aop_add
);
3266 const gdb_byte
*datastart
;
3268 const struct block
*b
;
3269 struct symbol
*framefunc
;
3271 b
= block_for_pc (expr
->scope
);
3274 error (_("No block found for address"));
3276 framefunc
= block_linkage_function (b
);
3279 error (_("No function found for block"));
3281 func_get_frame_base_dwarf_block (framefunc
, expr
->scope
,
3282 &datastart
, &datalen
);
3284 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3285 dwarf2_compile_expr_to_ax (expr
, loc
, addr_size
, datastart
,
3286 datastart
+ datalen
, per_cu
);
3287 if (loc
->kind
== axs_lvalue_register
)
3288 require_rvalue (expr
, loc
);
3292 ax_const_l (expr
, offset
);
3293 ax_simple (expr
, aop_add
);
3296 loc
->kind
= axs_lvalue_memory
;
3301 ax_simple (expr
, aop_dup
);
3305 ax_simple (expr
, aop_pop
);
3310 ax_pick (expr
, offset
);
3314 ax_simple (expr
, aop_swap
);
3322 ax_simple (expr
, aop_rot
);
3326 case DW_OP_deref_size
:
3330 if (op
== DW_OP_deref_size
)
3335 if (size
!= 1 && size
!= 2 && size
!= 4 && size
!= 8)
3336 error (_("Unsupported size %d in %s"),
3337 size
, get_DW_OP_name (op
));
3338 access_memory (arch
, expr
, size
* TARGET_CHAR_BIT
);
3343 /* Sign extend the operand. */
3344 ax_ext (expr
, addr_size_bits
);
3345 ax_simple (expr
, aop_dup
);
3346 ax_const_l (expr
, 0);
3347 ax_simple (expr
, aop_less_signed
);
3348 ax_simple (expr
, aop_log_not
);
3349 i
= ax_goto (expr
, aop_if_goto
);
3350 /* We have to emit 0 - X. */
3351 ax_const_l (expr
, 0);
3352 ax_simple (expr
, aop_swap
);
3353 ax_simple (expr
, aop_sub
);
3354 ax_label (expr
, i
, expr
->len
);
3358 /* No need to sign extend here. */
3359 ax_const_l (expr
, 0);
3360 ax_simple (expr
, aop_swap
);
3361 ax_simple (expr
, aop_sub
);
3365 /* Sign extend the operand. */
3366 ax_ext (expr
, addr_size_bits
);
3367 ax_simple (expr
, aop_bit_not
);
3370 case DW_OP_plus_uconst
:
3371 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3372 /* It would be really weird to emit `DW_OP_plus_uconst 0',
3373 but we micro-optimize anyhow. */
3376 ax_const_l (expr
, reg
);
3377 ax_simple (expr
, aop_add
);
3382 ax_simple (expr
, aop_bit_and
);
3386 /* Sign extend the operands. */
3387 ax_ext (expr
, addr_size_bits
);
3388 ax_simple (expr
, aop_swap
);
3389 ax_ext (expr
, addr_size_bits
);
3390 ax_simple (expr
, aop_swap
);
3391 ax_simple (expr
, aop_div_signed
);
3395 ax_simple (expr
, aop_sub
);
3399 ax_simple (expr
, aop_rem_unsigned
);
3403 ax_simple (expr
, aop_mul
);
3407 ax_simple (expr
, aop_bit_or
);
3411 ax_simple (expr
, aop_add
);
3415 ax_simple (expr
, aop_lsh
);
3419 ax_simple (expr
, aop_rsh_unsigned
);
3423 ax_simple (expr
, aop_rsh_signed
);
3427 ax_simple (expr
, aop_bit_xor
);
3431 /* Sign extend the operands. */
3432 ax_ext (expr
, addr_size_bits
);
3433 ax_simple (expr
, aop_swap
);
3434 ax_ext (expr
, addr_size_bits
);
3435 /* Note no swap here: A <= B is !(B < A). */
3436 ax_simple (expr
, aop_less_signed
);
3437 ax_simple (expr
, aop_log_not
);
3441 /* Sign extend the operands. */
3442 ax_ext (expr
, addr_size_bits
);
3443 ax_simple (expr
, aop_swap
);
3444 ax_ext (expr
, addr_size_bits
);
3445 ax_simple (expr
, aop_swap
);
3446 /* A >= B is !(A < B). */
3447 ax_simple (expr
, aop_less_signed
);
3448 ax_simple (expr
, aop_log_not
);
3452 /* Sign extend the operands. */
3453 ax_ext (expr
, addr_size_bits
);
3454 ax_simple (expr
, aop_swap
);
3455 ax_ext (expr
, addr_size_bits
);
3456 /* No need for a second swap here. */
3457 ax_simple (expr
, aop_equal
);
3461 /* Sign extend the operands. */
3462 ax_ext (expr
, addr_size_bits
);
3463 ax_simple (expr
, aop_swap
);
3464 ax_ext (expr
, addr_size_bits
);
3465 ax_simple (expr
, aop_swap
);
3466 ax_simple (expr
, aop_less_signed
);
3470 /* Sign extend the operands. */
3471 ax_ext (expr
, addr_size_bits
);
3472 ax_simple (expr
, aop_swap
);
3473 ax_ext (expr
, addr_size_bits
);
3474 /* Note no swap here: A > B is B < A. */
3475 ax_simple (expr
, aop_less_signed
);
3479 /* Sign extend the operands. */
3480 ax_ext (expr
, addr_size_bits
);
3481 ax_simple (expr
, aop_swap
);
3482 ax_ext (expr
, addr_size_bits
);
3483 /* No need for a swap here. */
3484 ax_simple (expr
, aop_equal
);
3485 ax_simple (expr
, aop_log_not
);
3488 case DW_OP_call_frame_cfa
:
3491 CORE_ADDR text_offset
;
3493 const gdb_byte
*cfa_start
, *cfa_end
;
3495 if (dwarf2_fetch_cfa_info (arch
, expr
->scope
, per_cu
,
3497 &text_offset
, &cfa_start
, &cfa_end
))
3500 ax_reg (expr
, regnum
);
3503 ax_const_l (expr
, off
);
3504 ax_simple (expr
, aop_add
);
3509 /* Another expression. */
3510 ax_const_l (expr
, text_offset
);
3511 dwarf2_compile_expr_to_ax (expr
, loc
, addr_size
, cfa_start
,
3515 loc
->kind
= axs_lvalue_memory
;
3519 case DW_OP_GNU_push_tls_address
:
3520 case DW_OP_form_tls_address
:
3524 case DW_OP_push_object_address
:
3529 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3531 i
= ax_goto (expr
, aop_goto
);
3532 dw_labels
.push_back (op_ptr
+ offset
- base
);
3533 patches
.push_back (i
);
3537 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3539 /* Zero extend the operand. */
3540 ax_zero_ext (expr
, addr_size_bits
);
3541 i
= ax_goto (expr
, aop_if_goto
);
3542 dw_labels
.push_back (op_ptr
+ offset
- base
);
3543 patches
.push_back (i
);
3550 case DW_OP_bit_piece
:
3552 uint64_t size
, offset
;
3554 if (op_ptr
- 1 == previous_piece
)
3555 error (_("Cannot translate empty pieces to agent expressions"));
3556 previous_piece
= op_ptr
- 1;
3558 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &size
);
3559 if (op
== DW_OP_piece
)
3565 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &offset
);
3567 if (bits_collected
+ size
> 8 * sizeof (LONGEST
))
3568 error (_("Expression pieces exceed word size"));
3570 /* Access the bits. */
3573 case axs_lvalue_register
:
3574 ax_reg (expr
, loc
->u
.reg
);
3577 case axs_lvalue_memory
:
3578 /* Offset the pointer, if needed. */
3581 ax_const_l (expr
, offset
/ 8);
3582 ax_simple (expr
, aop_add
);
3585 access_memory (arch
, expr
, size
);
3589 /* For a bits-big-endian target, shift up what we already
3590 have. For a bits-little-endian target, shift up the
3591 new data. Note that there is a potential bug here if
3592 the DWARF expression leaves multiple values on the
3594 if (bits_collected
> 0)
3596 if (bits_big_endian
)
3598 ax_simple (expr
, aop_swap
);
3599 ax_const_l (expr
, size
);
3600 ax_simple (expr
, aop_lsh
);
3601 /* We don't need a second swap here, because
3602 aop_bit_or is symmetric. */
3606 ax_const_l (expr
, size
);
3607 ax_simple (expr
, aop_lsh
);
3609 ax_simple (expr
, aop_bit_or
);
3612 bits_collected
+= size
;
3613 loc
->kind
= axs_rvalue
;
3617 case DW_OP_GNU_uninit
:
3623 struct dwarf2_locexpr_baton block
;
3624 int size
= (op
== DW_OP_call2
? 2 : 4);
3626 uoffset
= extract_unsigned_integer (op_ptr
, size
, byte_order
);
3629 cu_offset offset
= (cu_offset
) uoffset
;
3630 block
= dwarf2_fetch_die_loc_cu_off (offset
, per_cu
,
3633 /* DW_OP_call_ref is currently not supported. */
3634 gdb_assert (block
.per_cu
== per_cu
);
3636 dwarf2_compile_expr_to_ax (expr
, loc
, addr_size
, block
.data
,
3637 block
.data
+ block
.size
, per_cu
);
3641 case DW_OP_call_ref
:
3649 /* Patch all the branches we emitted. */
3650 for (i
= 0; i
< patches
.size (); ++i
)
3652 int targ
= offsets
[dw_labels
[i
]];
3654 internal_error (__FILE__
, __LINE__
, _("invalid label"));
3655 ax_label (expr
, patches
[i
], targ
);
3660 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
3661 evaluator to calculate the location. */
3662 static struct value
*
3663 locexpr_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
3665 struct dwarf2_locexpr_baton
*dlbaton
3666 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3669 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3670 dlbaton
->size
, dlbaton
->per_cu
);
3675 /* Return the value of SYMBOL in FRAME at (callee) FRAME's function
3676 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
3679 static struct value
*
3680 locexpr_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
3682 struct dwarf2_locexpr_baton
*dlbaton
3683 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3685 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3689 /* Implementation of get_symbol_read_needs from
3690 symbol_computed_ops. */
3692 static enum symbol_needs_kind
3693 locexpr_get_symbol_read_needs (struct symbol
*symbol
)
3695 struct dwarf2_locexpr_baton
*dlbaton
3696 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3698 return dwarf2_loc_desc_get_symbol_read_needs (dlbaton
->data
, dlbaton
->size
,
3702 /* Return true if DATA points to the end of a piece. END is one past
3703 the last byte in the expression. */
3706 piece_end_p (const gdb_byte
*data
, const gdb_byte
*end
)
3708 return data
== end
|| data
[0] == DW_OP_piece
|| data
[0] == DW_OP_bit_piece
;
3711 /* Helper for locexpr_describe_location_piece that finds the name of a
3715 locexpr_regname (struct gdbarch
*gdbarch
, int dwarf_regnum
)
3719 /* This doesn't use dwarf_reg_to_regnum_or_error on purpose.
3720 We'd rather print *something* here than throw an error. */
3721 regnum
= dwarf_reg_to_regnum (gdbarch
, dwarf_regnum
);
3722 /* gdbarch_register_name may just return "", return something more
3723 descriptive for bad register numbers. */
3726 /* The text is output as "$bad_register_number".
3727 That is why we use the underscores. */
3728 return _("bad_register_number");
3730 return gdbarch_register_name (gdbarch
, regnum
);
3733 /* Nicely describe a single piece of a location, returning an updated
3734 position in the bytecode sequence. This function cannot recognize
3735 all locations; if a location is not recognized, it simply returns
3736 DATA. If there is an error during reading, e.g. we run off the end
3737 of the buffer, an error is thrown. */
3739 static const gdb_byte
*
3740 locexpr_describe_location_piece (struct symbol
*symbol
, struct ui_file
*stream
,
3741 CORE_ADDR addr
, struct objfile
*objfile
,
3742 struct dwarf2_per_cu_data
*per_cu
,
3743 const gdb_byte
*data
, const gdb_byte
*end
,
3744 unsigned int addr_size
)
3746 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
3749 if (data
[0] >= DW_OP_reg0
&& data
[0] <= DW_OP_reg31
)
3751 fprintf_filtered (stream
, _("a variable in $%s"),
3752 locexpr_regname (gdbarch
, data
[0] - DW_OP_reg0
));
3755 else if (data
[0] == DW_OP_regx
)
3759 data
= safe_read_uleb128 (data
+ 1, end
, ®
);
3760 fprintf_filtered (stream
, _("a variable in $%s"),
3761 locexpr_regname (gdbarch
, reg
));
3763 else if (data
[0] == DW_OP_fbreg
)
3765 const struct block
*b
;
3766 struct symbol
*framefunc
;
3768 int64_t frame_offset
;
3769 const gdb_byte
*base_data
, *new_data
, *save_data
= data
;
3771 int64_t base_offset
= 0;
3773 new_data
= safe_read_sleb128 (data
+ 1, end
, &frame_offset
);
3774 if (!piece_end_p (new_data
, end
))
3778 b
= block_for_pc (addr
);
3781 error (_("No block found for address for symbol \"%s\"."),
3782 SYMBOL_PRINT_NAME (symbol
));
3784 framefunc
= block_linkage_function (b
);
3787 error (_("No function found for block for symbol \"%s\"."),
3788 SYMBOL_PRINT_NAME (symbol
));
3790 func_get_frame_base_dwarf_block (framefunc
, addr
, &base_data
, &base_size
);
3792 if (base_data
[0] >= DW_OP_breg0
&& base_data
[0] <= DW_OP_breg31
)
3794 const gdb_byte
*buf_end
;
3796 frame_reg
= base_data
[0] - DW_OP_breg0
;
3797 buf_end
= safe_read_sleb128 (base_data
+ 1, base_data
+ base_size
,
3799 if (buf_end
!= base_data
+ base_size
)
3800 error (_("Unexpected opcode after "
3801 "DW_OP_breg%u for symbol \"%s\"."),
3802 frame_reg
, SYMBOL_PRINT_NAME (symbol
));
3804 else if (base_data
[0] >= DW_OP_reg0
&& base_data
[0] <= DW_OP_reg31
)
3806 /* The frame base is just the register, with no offset. */
3807 frame_reg
= base_data
[0] - DW_OP_reg0
;
3812 /* We don't know what to do with the frame base expression,
3813 so we can't trace this variable; give up. */
3817 fprintf_filtered (stream
,
3818 _("a variable at frame base reg $%s offset %s+%s"),
3819 locexpr_regname (gdbarch
, frame_reg
),
3820 plongest (base_offset
), plongest (frame_offset
));
3822 else if (data
[0] >= DW_OP_breg0
&& data
[0] <= DW_OP_breg31
3823 && piece_end_p (data
, end
))
3827 data
= safe_read_sleb128 (data
+ 1, end
, &offset
);
3829 fprintf_filtered (stream
,
3830 _("a variable at offset %s from base reg $%s"),
3832 locexpr_regname (gdbarch
, data
[0] - DW_OP_breg0
));
3835 /* The location expression for a TLS variable looks like this (on a
3838 DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
3839 (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
3841 0x3 is the encoding for DW_OP_addr, which has an operand as long
3842 as the size of an address on the target machine (here is 8
3843 bytes). Note that more recent version of GCC emit DW_OP_const4u
3844 or DW_OP_const8u, depending on address size, rather than
3845 DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address.
3846 The operand represents the offset at which the variable is within
3847 the thread local storage. */
3849 else if (data
+ 1 + addr_size
< end
3850 && (data
[0] == DW_OP_addr
3851 || (addr_size
== 4 && data
[0] == DW_OP_const4u
)
3852 || (addr_size
== 8 && data
[0] == DW_OP_const8u
))
3853 && (data
[1 + addr_size
] == DW_OP_GNU_push_tls_address
3854 || data
[1 + addr_size
] == DW_OP_form_tls_address
)
3855 && piece_end_p (data
+ 2 + addr_size
, end
))
3858 offset
= extract_unsigned_integer (data
+ 1, addr_size
,
3859 gdbarch_byte_order (gdbarch
));
3861 fprintf_filtered (stream
,
3862 _("a thread-local variable at offset 0x%s "
3863 "in the thread-local storage for `%s'"),
3864 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3866 data
+= 1 + addr_size
+ 1;
3869 /* With -gsplit-dwarf a TLS variable can also look like this:
3870 DW_AT_location : 3 byte block: fc 4 e0
3871 (DW_OP_GNU_const_index: 4;
3872 DW_OP_GNU_push_tls_address) */
3873 else if (data
+ 3 <= end
3874 && data
+ 1 + (leb128_size
= skip_leb128 (data
+ 1, end
)) < end
3875 && data
[0] == DW_OP_GNU_const_index
3877 && (data
[1 + leb128_size
] == DW_OP_GNU_push_tls_address
3878 || data
[1 + leb128_size
] == DW_OP_form_tls_address
)
3879 && piece_end_p (data
+ 2 + leb128_size
, end
))
3883 data
= safe_read_uleb128 (data
+ 1, end
, &offset
);
3884 offset
= dwarf2_read_addr_index (per_cu
, offset
);
3885 fprintf_filtered (stream
,
3886 _("a thread-local variable at offset 0x%s "
3887 "in the thread-local storage for `%s'"),
3888 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3892 else if (data
[0] >= DW_OP_lit0
3893 && data
[0] <= DW_OP_lit31
3895 && data
[1] == DW_OP_stack_value
)
3897 fprintf_filtered (stream
, _("the constant %d"), data
[0] - DW_OP_lit0
);
3904 /* Disassemble an expression, stopping at the end of a piece or at the
3905 end of the expression. Returns a pointer to the next unread byte
3906 in the input expression. If ALL is nonzero, then this function
3907 will keep going until it reaches the end of the expression.
3908 If there is an error during reading, e.g. we run off the end
3909 of the buffer, an error is thrown. */
3911 static const gdb_byte
*
3912 disassemble_dwarf_expression (struct ui_file
*stream
,
3913 struct gdbarch
*arch
, unsigned int addr_size
,
3914 int offset_size
, const gdb_byte
*start
,
3915 const gdb_byte
*data
, const gdb_byte
*end
,
3916 int indent
, int all
,
3917 struct dwarf2_per_cu_data
*per_cu
)
3921 || (data
[0] != DW_OP_piece
&& data
[0] != DW_OP_bit_piece
)))
3923 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *data
++;
3928 name
= get_DW_OP_name (op
);
3931 error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
3932 op
, (long) (data
- 1 - start
));
3933 fprintf_filtered (stream
, " %*ld: %s", indent
+ 4,
3934 (long) (data
- 1 - start
), name
);
3939 ul
= extract_unsigned_integer (data
, addr_size
,
3940 gdbarch_byte_order (arch
));
3942 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
3946 ul
= extract_unsigned_integer (data
, 1, gdbarch_byte_order (arch
));
3948 fprintf_filtered (stream
, " %s", pulongest (ul
));
3951 l
= extract_signed_integer (data
, 1, gdbarch_byte_order (arch
));
3953 fprintf_filtered (stream
, " %s", plongest (l
));
3956 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
3958 fprintf_filtered (stream
, " %s", pulongest (ul
));
3961 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
3963 fprintf_filtered (stream
, " %s", plongest (l
));
3966 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
3968 fprintf_filtered (stream
, " %s", pulongest (ul
));
3971 l
= extract_signed_integer (data
, 4, gdbarch_byte_order (arch
));
3973 fprintf_filtered (stream
, " %s", plongest (l
));
3976 ul
= extract_unsigned_integer (data
, 8, gdbarch_byte_order (arch
));
3978 fprintf_filtered (stream
, " %s", pulongest (ul
));
3981 l
= extract_signed_integer (data
, 8, gdbarch_byte_order (arch
));
3983 fprintf_filtered (stream
, " %s", plongest (l
));
3986 data
= safe_read_uleb128 (data
, end
, &ul
);
3987 fprintf_filtered (stream
, " %s", pulongest (ul
));
3990 data
= safe_read_sleb128 (data
, end
, &l
);
3991 fprintf_filtered (stream
, " %s", plongest (l
));
4026 fprintf_filtered (stream
, " [$%s]",
4027 locexpr_regname (arch
, op
- DW_OP_reg0
));
4031 data
= safe_read_uleb128 (data
, end
, &ul
);
4032 fprintf_filtered (stream
, " %s [$%s]", pulongest (ul
),
4033 locexpr_regname (arch
, (int) ul
));
4036 case DW_OP_implicit_value
:
4037 data
= safe_read_uleb128 (data
, end
, &ul
);
4039 fprintf_filtered (stream
, " %s", pulongest (ul
));
4074 data
= safe_read_sleb128 (data
, end
, &l
);
4075 fprintf_filtered (stream
, " %s [$%s]", plongest (l
),
4076 locexpr_regname (arch
, op
- DW_OP_breg0
));
4080 data
= safe_read_uleb128 (data
, end
, &ul
);
4081 data
= safe_read_sleb128 (data
, end
, &l
);
4082 fprintf_filtered (stream
, " register %s [$%s] offset %s",
4084 locexpr_regname (arch
, (int) ul
),
4089 data
= safe_read_sleb128 (data
, end
, &l
);
4090 fprintf_filtered (stream
, " %s", plongest (l
));
4093 case DW_OP_xderef_size
:
4094 case DW_OP_deref_size
:
4096 fprintf_filtered (stream
, " %d", *data
);
4100 case DW_OP_plus_uconst
:
4101 data
= safe_read_uleb128 (data
, end
, &ul
);
4102 fprintf_filtered (stream
, " %s", pulongest (ul
));
4106 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4108 fprintf_filtered (stream
, " to %ld",
4109 (long) (data
+ l
- start
));
4113 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4115 fprintf_filtered (stream
, " %ld",
4116 (long) (data
+ l
- start
));
4120 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4122 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 2));
4126 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4128 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4131 case DW_OP_call_ref
:
4132 ul
= extract_unsigned_integer (data
, offset_size
,
4133 gdbarch_byte_order (arch
));
4134 data
+= offset_size
;
4135 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4139 data
= safe_read_uleb128 (data
, end
, &ul
);
4140 fprintf_filtered (stream
, " %s (bytes)", pulongest (ul
));
4143 case DW_OP_bit_piece
:
4147 data
= safe_read_uleb128 (data
, end
, &ul
);
4148 data
= safe_read_uleb128 (data
, end
, &offset
);
4149 fprintf_filtered (stream
, " size %s offset %s (bits)",
4150 pulongest (ul
), pulongest (offset
));
4154 case DW_OP_implicit_pointer
:
4155 case DW_OP_GNU_implicit_pointer
:
4157 ul
= extract_unsigned_integer (data
, offset_size
,
4158 gdbarch_byte_order (arch
));
4159 data
+= offset_size
;
4161 data
= safe_read_sleb128 (data
, end
, &l
);
4163 fprintf_filtered (stream
, " DIE %s offset %s",
4164 phex_nz (ul
, offset_size
),
4169 case DW_OP_deref_type
:
4170 case DW_OP_GNU_deref_type
:
4172 int addr_size
= *data
++;
4175 data
= safe_read_uleb128 (data
, end
, &ul
);
4176 cu_offset offset
= (cu_offset
) ul
;
4177 type
= dwarf2_get_die_type (offset
, per_cu
);
4178 fprintf_filtered (stream
, "<");
4179 type_print (type
, "", stream
, -1);
4180 fprintf_filtered (stream
, " [0x%s]> %d",
4181 phex_nz (to_underlying (offset
), 0),
4186 case DW_OP_const_type
:
4187 case DW_OP_GNU_const_type
:
4191 data
= safe_read_uleb128 (data
, end
, &ul
);
4192 cu_offset type_die
= (cu_offset
) ul
;
4193 type
= dwarf2_get_die_type (type_die
, per_cu
);
4194 fprintf_filtered (stream
, "<");
4195 type_print (type
, "", stream
, -1);
4196 fprintf_filtered (stream
, " [0x%s]>",
4197 phex_nz (to_underlying (type_die
), 0));
4201 case DW_OP_regval_type
:
4202 case DW_OP_GNU_regval_type
:
4207 data
= safe_read_uleb128 (data
, end
, ®
);
4208 data
= safe_read_uleb128 (data
, end
, &ul
);
4209 cu_offset type_die
= (cu_offset
) ul
;
4211 type
= dwarf2_get_die_type (type_die
, per_cu
);
4212 fprintf_filtered (stream
, "<");
4213 type_print (type
, "", stream
, -1);
4214 fprintf_filtered (stream
, " [0x%s]> [$%s]",
4215 phex_nz (to_underlying (type_die
), 0),
4216 locexpr_regname (arch
, reg
));
4221 case DW_OP_GNU_convert
:
4222 case DW_OP_reinterpret
:
4223 case DW_OP_GNU_reinterpret
:
4225 data
= safe_read_uleb128 (data
, end
, &ul
);
4226 cu_offset type_die
= (cu_offset
) ul
;
4228 if (to_underlying (type_die
) == 0)
4229 fprintf_filtered (stream
, "<0>");
4234 type
= dwarf2_get_die_type (type_die
, per_cu
);
4235 fprintf_filtered (stream
, "<");
4236 type_print (type
, "", stream
, -1);
4237 fprintf_filtered (stream
, " [0x%s]>",
4238 phex_nz (to_underlying (type_die
), 0));
4243 case DW_OP_entry_value
:
4244 case DW_OP_GNU_entry_value
:
4245 data
= safe_read_uleb128 (data
, end
, &ul
);
4246 fputc_filtered ('\n', stream
);
4247 disassemble_dwarf_expression (stream
, arch
, addr_size
, offset_size
,
4248 start
, data
, data
+ ul
, indent
+ 2,
4253 case DW_OP_GNU_parameter_ref
:
4254 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4256 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4259 case DW_OP_GNU_addr_index
:
4260 data
= safe_read_uleb128 (data
, end
, &ul
);
4261 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4262 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
4264 case DW_OP_GNU_const_index
:
4265 data
= safe_read_uleb128 (data
, end
, &ul
);
4266 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4267 fprintf_filtered (stream
, " %s", pulongest (ul
));
4271 fprintf_filtered (stream
, "\n");
4277 /* Describe a single location, which may in turn consist of multiple
4281 locexpr_describe_location_1 (struct symbol
*symbol
, CORE_ADDR addr
,
4282 struct ui_file
*stream
,
4283 const gdb_byte
*data
, size_t size
,
4284 struct objfile
*objfile
, unsigned int addr_size
,
4285 int offset_size
, struct dwarf2_per_cu_data
*per_cu
)
4287 const gdb_byte
*end
= data
+ size
;
4288 int first_piece
= 1, bad
= 0;
4292 const gdb_byte
*here
= data
;
4293 int disassemble
= 1;
4298 fprintf_filtered (stream
, _(", and "));
4300 if (!dwarf_always_disassemble
)
4302 data
= locexpr_describe_location_piece (symbol
, stream
,
4303 addr
, objfile
, per_cu
,
4304 data
, end
, addr_size
);
4305 /* If we printed anything, or if we have an empty piece,
4306 then don't disassemble. */
4308 || data
[0] == DW_OP_piece
4309 || data
[0] == DW_OP_bit_piece
)
4314 fprintf_filtered (stream
, _("a complex DWARF expression:\n"));
4315 data
= disassemble_dwarf_expression (stream
,
4316 get_objfile_arch (objfile
),
4317 addr_size
, offset_size
, data
,
4319 dwarf_always_disassemble
,
4325 int empty
= data
== here
;
4328 fprintf_filtered (stream
, " ");
4329 if (data
[0] == DW_OP_piece
)
4333 data
= safe_read_uleb128 (data
+ 1, end
, &bytes
);
4336 fprintf_filtered (stream
, _("an empty %s-byte piece"),
4339 fprintf_filtered (stream
, _(" [%s-byte piece]"),
4342 else if (data
[0] == DW_OP_bit_piece
)
4344 uint64_t bits
, offset
;
4346 data
= safe_read_uleb128 (data
+ 1, end
, &bits
);
4347 data
= safe_read_uleb128 (data
, end
, &offset
);
4350 fprintf_filtered (stream
,
4351 _("an empty %s-bit piece"),
4354 fprintf_filtered (stream
,
4355 _(" [%s-bit piece, offset %s bits]"),
4356 pulongest (bits
), pulongest (offset
));
4366 if (bad
|| data
> end
)
4367 error (_("Corrupted DWARF2 expression for \"%s\"."),
4368 SYMBOL_PRINT_NAME (symbol
));
4371 /* Print a natural-language description of SYMBOL to STREAM. This
4372 version is for a symbol with a single location. */
4375 locexpr_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4376 struct ui_file
*stream
)
4378 struct dwarf2_locexpr_baton
*dlbaton
4379 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4380 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4381 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4382 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4384 locexpr_describe_location_1 (symbol
, addr
, stream
,
4385 dlbaton
->data
, dlbaton
->size
,
4386 objfile
, addr_size
, offset_size
,
4390 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4391 any necessary bytecode in AX. */
4394 locexpr_tracepoint_var_ref (struct symbol
*symbol
, struct agent_expr
*ax
,
4395 struct axs_value
*value
)
4397 struct dwarf2_locexpr_baton
*dlbaton
4398 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4399 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4401 if (dlbaton
->size
== 0)
4402 value
->optimized_out
= 1;
4404 dwarf2_compile_expr_to_ax (ax
, value
, addr_size
, dlbaton
->data
,
4405 dlbaton
->data
+ dlbaton
->size
, dlbaton
->per_cu
);
4408 /* symbol_computed_ops 'generate_c_location' method. */
4411 locexpr_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4412 struct gdbarch
*gdbarch
,
4413 unsigned char *registers_used
,
4414 CORE_ADDR pc
, const char *result_name
)
4416 struct dwarf2_locexpr_baton
*dlbaton
4417 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (sym
);
4418 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4420 if (dlbaton
->size
== 0)
4421 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4423 compile_dwarf_expr_to_c (stream
, result_name
,
4424 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4425 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4429 /* The set of location functions used with the DWARF-2 expression
4431 const struct symbol_computed_ops dwarf2_locexpr_funcs
= {
4432 locexpr_read_variable
,
4433 locexpr_read_variable_at_entry
,
4434 locexpr_get_symbol_read_needs
,
4435 locexpr_describe_location
,
4436 0, /* location_has_loclist */
4437 locexpr_tracepoint_var_ref
,
4438 locexpr_generate_c_location
4442 /* Wrapper functions for location lists. These generally find
4443 the appropriate location expression and call something above. */
4445 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
4446 evaluator to calculate the location. */
4447 static struct value
*
4448 loclist_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
4450 struct dwarf2_loclist_baton
*dlbaton
4451 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4453 const gdb_byte
*data
;
4455 CORE_ADDR pc
= frame
? get_frame_address_in_block (frame
) : 0;
4457 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4458 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, data
, size
,
4464 /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
4465 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
4468 Function always returns non-NULL value, it may be marked optimized out if
4469 inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
4470 if it cannot resolve the parameter for any reason. */
4472 static struct value
*
4473 loclist_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
4475 struct dwarf2_loclist_baton
*dlbaton
4476 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4477 const gdb_byte
*data
;
4481 if (frame
== NULL
|| !get_frame_func_if_available (frame
, &pc
))
4482 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4484 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4486 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4488 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, data
, size
);
4491 /* Implementation of get_symbol_read_needs from
4492 symbol_computed_ops. */
4494 static enum symbol_needs_kind
4495 loclist_symbol_needs (struct symbol
*symbol
)
4497 /* If there's a location list, then assume we need to have a frame
4498 to choose the appropriate location expression. With tracking of
4499 global variables this is not necessarily true, but such tracking
4500 is disabled in GCC at the moment until we figure out how to
4503 return SYMBOL_NEEDS_FRAME
;
4506 /* Print a natural-language description of SYMBOL to STREAM. This
4507 version applies when there is a list of different locations, each
4508 with a specified address range. */
4511 loclist_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4512 struct ui_file
*stream
)
4514 struct dwarf2_loclist_baton
*dlbaton
4515 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4516 const gdb_byte
*loc_ptr
, *buf_end
;
4517 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4518 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
4519 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
4520 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4521 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4522 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
4523 /* Adjust base_address for relocatable objects. */
4524 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
4525 CORE_ADDR base_address
= dlbaton
->base_address
+ base_offset
;
4528 loc_ptr
= dlbaton
->data
;
4529 buf_end
= dlbaton
->data
+ dlbaton
->size
;
4531 fprintf_filtered (stream
, _("multi-location:\n"));
4533 /* Iterate through locations until we run out. */
4536 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
4538 enum debug_loc_kind kind
;
4539 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
4541 if (dlbaton
->from_dwo
)
4542 kind
= decode_debug_loc_dwo_addresses (dlbaton
->per_cu
,
4543 loc_ptr
, buf_end
, &new_ptr
,
4544 &low
, &high
, byte_order
);
4546 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
4548 byte_order
, addr_size
,
4553 case DEBUG_LOC_END_OF_LIST
:
4556 case DEBUG_LOC_BASE_ADDRESS
:
4557 base_address
= high
+ base_offset
;
4558 fprintf_filtered (stream
, _(" Base address %s"),
4559 paddress (gdbarch
, base_address
));
4561 case DEBUG_LOC_START_END
:
4562 case DEBUG_LOC_START_LENGTH
:
4564 case DEBUG_LOC_BUFFER_OVERFLOW
:
4565 case DEBUG_LOC_INVALID_ENTRY
:
4566 error (_("Corrupted DWARF expression for symbol \"%s\"."),
4567 SYMBOL_PRINT_NAME (symbol
));
4569 gdb_assert_not_reached ("bad debug_loc_kind");
4572 /* Otherwise, a location expression entry. */
4573 low
+= base_address
;
4574 high
+= base_address
;
4576 low
= gdbarch_adjust_dwarf2_addr (gdbarch
, low
);
4577 high
= gdbarch_adjust_dwarf2_addr (gdbarch
, high
);
4579 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
4582 /* (It would improve readability to print only the minimum
4583 necessary digits of the second number of the range.) */
4584 fprintf_filtered (stream
, _(" Range %s-%s: "),
4585 paddress (gdbarch
, low
), paddress (gdbarch
, high
));
4587 /* Now describe this particular location. */
4588 locexpr_describe_location_1 (symbol
, low
, stream
, loc_ptr
, length
,
4589 objfile
, addr_size
, offset_size
,
4592 fprintf_filtered (stream
, "\n");
4598 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4599 any necessary bytecode in AX. */
4601 loclist_tracepoint_var_ref (struct symbol
*symbol
, struct agent_expr
*ax
,
4602 struct axs_value
*value
)
4604 struct dwarf2_loclist_baton
*dlbaton
4605 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4606 const gdb_byte
*data
;
4608 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4610 data
= dwarf2_find_location_expression (dlbaton
, &size
, ax
->scope
);
4612 value
->optimized_out
= 1;
4614 dwarf2_compile_expr_to_ax (ax
, value
, addr_size
, data
, data
+ size
,
4618 /* symbol_computed_ops 'generate_c_location' method. */
4621 loclist_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4622 struct gdbarch
*gdbarch
,
4623 unsigned char *registers_used
,
4624 CORE_ADDR pc
, const char *result_name
)
4626 struct dwarf2_loclist_baton
*dlbaton
4627 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (sym
);
4628 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4629 const gdb_byte
*data
;
4632 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4634 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4636 compile_dwarf_expr_to_c (stream
, result_name
,
4637 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4642 /* The set of location functions used with the DWARF-2 expression
4643 evaluator and location lists. */
4644 const struct symbol_computed_ops dwarf2_loclist_funcs
= {
4645 loclist_read_variable
,
4646 loclist_read_variable_at_entry
,
4647 loclist_symbol_needs
,
4648 loclist_describe_location
,
4649 1, /* location_has_loclist */
4650 loclist_tracepoint_var_ref
,
4651 loclist_generate_c_location
4655 _initialize_dwarf2loc (void)
4657 add_setshow_zuinteger_cmd ("entry-values", class_maintenance
,
4658 &entry_values_debug
,
4659 _("Set entry values and tail call frames "
4661 _("Show entry values and tail call frames "
4663 _("When non-zero, the process of determining "
4664 "parameter values from function entry point "
4665 "and tail call frames will be printed."),
4667 show_entry_values_debug
,
4668 &setdebuglist
, &showdebuglist
);
4671 selftests::register_test ("copy_bitwise", selftests::copy_bitwise_tests
);