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"
47 extern int dwarf_always_disassemble
;
49 static struct value
*dwarf2_evaluate_loc_desc_full (struct type
*type
,
50 struct frame_info
*frame
,
53 struct dwarf2_per_cu_data
*per_cu
,
54 struct type
*subobj_type
,
55 LONGEST subobj_byte_offset
);
57 static struct call_site_parameter
*dwarf_expr_reg_to_entry_parameter
58 (struct frame_info
*frame
,
59 enum call_site_parameter_kind kind
,
60 union call_site_parameter_u kind_u
,
61 struct dwarf2_per_cu_data
**per_cu_return
);
63 /* Until these have formal names, we define these here.
64 ref: http://gcc.gnu.org/wiki/DebugFission
65 Each entry in .debug_loc.dwo begins with a byte that describes the entry,
66 and is then followed by data specific to that entry. */
70 /* Indicates the end of the list of entries. */
71 DEBUG_LOC_END_OF_LIST
= 0,
73 /* This is followed by an unsigned LEB128 number that is an index into
74 .debug_addr and specifies the base address for all following entries. */
75 DEBUG_LOC_BASE_ADDRESS
= 1,
77 /* This is followed by two unsigned LEB128 numbers that are indices into
78 .debug_addr and specify the beginning and ending addresses, and then
79 a normal location expression as in .debug_loc. */
80 DEBUG_LOC_START_END
= 2,
82 /* This is followed by an unsigned LEB128 number that is an index into
83 .debug_addr and specifies the beginning address, and a 4 byte unsigned
84 number that specifies the length, and then a normal location expression
86 DEBUG_LOC_START_LENGTH
= 3,
88 /* An internal value indicating there is insufficient data. */
89 DEBUG_LOC_BUFFER_OVERFLOW
= -1,
91 /* An internal value indicating an invalid kind of entry was found. */
92 DEBUG_LOC_INVALID_ENTRY
= -2
95 /* Helper function which throws an error if a synthetic pointer is
99 invalid_synthetic_pointer (void)
101 error (_("access outside bounds of object "
102 "referenced via synthetic pointer"));
105 /* Decode the addresses in a non-dwo .debug_loc entry.
106 A pointer to the next byte to examine is returned in *NEW_PTR.
107 The encoded low,high addresses are return in *LOW,*HIGH.
108 The result indicates the kind of entry found. */
110 static enum debug_loc_kind
111 decode_debug_loc_addresses (const gdb_byte
*loc_ptr
, const gdb_byte
*buf_end
,
112 const gdb_byte
**new_ptr
,
113 CORE_ADDR
*low
, CORE_ADDR
*high
,
114 enum bfd_endian byte_order
,
115 unsigned int addr_size
,
118 CORE_ADDR base_mask
= ~(~(CORE_ADDR
)1 << (addr_size
* 8 - 1));
120 if (buf_end
- loc_ptr
< 2 * addr_size
)
121 return DEBUG_LOC_BUFFER_OVERFLOW
;
124 *low
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
126 *low
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
127 loc_ptr
+= addr_size
;
130 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
132 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
133 loc_ptr
+= addr_size
;
137 /* A base-address-selection entry. */
138 if ((*low
& base_mask
) == base_mask
)
139 return DEBUG_LOC_BASE_ADDRESS
;
141 /* An end-of-list entry. */
142 if (*low
== 0 && *high
== 0)
143 return DEBUG_LOC_END_OF_LIST
;
145 return DEBUG_LOC_START_END
;
148 /* Decode the addresses in .debug_loclists entry.
149 A pointer to the next byte to examine is returned in *NEW_PTR.
150 The encoded low,high addresses are return in *LOW,*HIGH.
151 The result indicates the kind of entry found. */
153 static enum debug_loc_kind
154 decode_debug_loclists_addresses (struct dwarf2_per_cu_data
*per_cu
,
155 const gdb_byte
*loc_ptr
,
156 const gdb_byte
*buf_end
,
157 const gdb_byte
**new_ptr
,
158 CORE_ADDR
*low
, CORE_ADDR
*high
,
159 enum bfd_endian byte_order
,
160 unsigned int addr_size
,
165 if (loc_ptr
== buf_end
)
166 return DEBUG_LOC_BUFFER_OVERFLOW
;
170 case DW_LLE_end_of_list
:
172 return DEBUG_LOC_END_OF_LIST
;
173 case DW_LLE_base_address
:
174 if (loc_ptr
+ addr_size
> buf_end
)
175 return DEBUG_LOC_BUFFER_OVERFLOW
;
177 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
179 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
180 loc_ptr
+= addr_size
;
182 return DEBUG_LOC_BASE_ADDRESS
;
183 case DW_LLE_offset_pair
:
184 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
186 return DEBUG_LOC_BUFFER_OVERFLOW
;
188 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &u64
);
190 return DEBUG_LOC_BUFFER_OVERFLOW
;
193 return DEBUG_LOC_START_END
;
195 return DEBUG_LOC_INVALID_ENTRY
;
199 /* Decode the addresses in .debug_loc.dwo entry.
200 A pointer to the next byte to examine is returned in *NEW_PTR.
201 The encoded low,high addresses are return in *LOW,*HIGH.
202 The result indicates the kind of entry found. */
204 static enum debug_loc_kind
205 decode_debug_loc_dwo_addresses (struct dwarf2_per_cu_data
*per_cu
,
206 const gdb_byte
*loc_ptr
,
207 const gdb_byte
*buf_end
,
208 const gdb_byte
**new_ptr
,
209 CORE_ADDR
*low
, CORE_ADDR
*high
,
210 enum bfd_endian byte_order
)
212 uint64_t low_index
, high_index
;
214 if (loc_ptr
== buf_end
)
215 return DEBUG_LOC_BUFFER_OVERFLOW
;
219 case DW_LLE_GNU_end_of_list_entry
:
221 return DEBUG_LOC_END_OF_LIST
;
222 case DW_LLE_GNU_base_address_selection_entry
:
224 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
226 return DEBUG_LOC_BUFFER_OVERFLOW
;
227 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
229 return DEBUG_LOC_BASE_ADDRESS
;
230 case DW_LLE_GNU_start_end_entry
:
231 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
233 return DEBUG_LOC_BUFFER_OVERFLOW
;
234 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
235 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
237 return DEBUG_LOC_BUFFER_OVERFLOW
;
238 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
240 return DEBUG_LOC_START_END
;
241 case DW_LLE_GNU_start_length_entry
:
242 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
244 return DEBUG_LOC_BUFFER_OVERFLOW
;
245 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
246 if (loc_ptr
+ 4 > buf_end
)
247 return DEBUG_LOC_BUFFER_OVERFLOW
;
249 *high
+= extract_unsigned_integer (loc_ptr
, 4, byte_order
);
250 *new_ptr
= loc_ptr
+ 4;
251 return DEBUG_LOC_START_LENGTH
;
253 return DEBUG_LOC_INVALID_ENTRY
;
257 /* A function for dealing with location lists. Given a
258 symbol baton (BATON) and a pc value (PC), find the appropriate
259 location expression, set *LOCEXPR_LENGTH, and return a pointer
260 to the beginning of the expression. Returns NULL on failure.
262 For now, only return the first matching location expression; there
263 can be more than one in the list. */
266 dwarf2_find_location_expression (struct dwarf2_loclist_baton
*baton
,
267 size_t *locexpr_length
, CORE_ADDR pc
)
269 struct objfile
*objfile
= dwarf2_per_cu_objfile (baton
->per_cu
);
270 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
271 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
272 unsigned int addr_size
= dwarf2_per_cu_addr_size (baton
->per_cu
);
273 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
274 /* Adjust base_address for relocatable objects. */
275 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (baton
->per_cu
);
276 CORE_ADDR base_address
= baton
->base_address
+ base_offset
;
277 const gdb_byte
*loc_ptr
, *buf_end
;
279 loc_ptr
= baton
->data
;
280 buf_end
= baton
->data
+ baton
->size
;
284 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
286 enum debug_loc_kind kind
;
287 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
290 kind
= decode_debug_loc_dwo_addresses (baton
->per_cu
,
291 loc_ptr
, buf_end
, &new_ptr
,
292 &low
, &high
, byte_order
);
293 else if (dwarf2_version (baton
->per_cu
) < 5)
294 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
296 byte_order
, addr_size
,
299 kind
= decode_debug_loclists_addresses (baton
->per_cu
,
300 loc_ptr
, buf_end
, &new_ptr
,
301 &low
, &high
, byte_order
,
302 addr_size
, signed_addr_p
);
307 case DEBUG_LOC_END_OF_LIST
:
310 case DEBUG_LOC_BASE_ADDRESS
:
311 base_address
= high
+ base_offset
;
313 case DEBUG_LOC_START_END
:
314 case DEBUG_LOC_START_LENGTH
:
316 case DEBUG_LOC_BUFFER_OVERFLOW
:
317 case DEBUG_LOC_INVALID_ENTRY
:
318 error (_("dwarf2_find_location_expression: "
319 "Corrupted DWARF expression."));
321 gdb_assert_not_reached ("bad debug_loc_kind");
324 /* Otherwise, a location expression entry.
325 If the entry is from a DWO, don't add base address: the entry is from
326 .debug_addr which already has the DWARF "base address". We still add
327 base_offset in case we're debugging a PIE executable. */
336 high
+= base_address
;
339 if (dwarf2_version (baton
->per_cu
) < 5)
341 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
346 unsigned int bytes_read
;
348 length
= read_unsigned_leb128 (NULL
, loc_ptr
, &bytes_read
);
349 loc_ptr
+= bytes_read
;
352 if (low
== high
&& pc
== low
)
354 /* This is entry PC record present only at entry point
355 of a function. Verify it is really the function entry point. */
357 const struct block
*pc_block
= block_for_pc (pc
);
358 struct symbol
*pc_func
= NULL
;
361 pc_func
= block_linkage_function (pc_block
);
363 if (pc_func
&& pc
== BLOCK_START (SYMBOL_BLOCK_VALUE (pc_func
)))
365 *locexpr_length
= length
;
370 if (pc
>= low
&& pc
< high
)
372 *locexpr_length
= length
;
380 /* This is the baton used when performing dwarf2 expression
382 struct dwarf_expr_baton
384 struct frame_info
*frame
;
385 struct dwarf2_per_cu_data
*per_cu
;
386 CORE_ADDR obj_address
;
389 /* Implement find_frame_base_location method for LOC_BLOCK functions using
390 DWARF expression for its DW_AT_frame_base. */
393 locexpr_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
394 const gdb_byte
**start
, size_t *length
)
396 struct dwarf2_locexpr_baton
*symbaton
397 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
399 *length
= symbaton
->size
;
400 *start
= symbaton
->data
;
403 /* Implement the struct symbol_block_ops::get_frame_base method for
404 LOC_BLOCK functions using a DWARF expression as its DW_AT_frame_base. */
407 locexpr_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
409 struct gdbarch
*gdbarch
;
411 struct dwarf2_locexpr_baton
*dlbaton
;
412 const gdb_byte
*start
;
414 struct value
*result
;
416 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
417 Thus, it's supposed to provide the find_frame_base_location method as
419 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
421 gdbarch
= get_frame_arch (frame
);
422 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
423 dlbaton
= (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
425 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
426 (framefunc
, get_frame_pc (frame
), &start
, &length
);
427 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
430 /* The DW_AT_frame_base attribute contains a location description which
431 computes the base address itself. However, the call to
432 dwarf2_evaluate_loc_desc returns a value representing a variable at
433 that address. The frame base address is thus this variable's
435 return value_address (result
);
438 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
439 function uses DWARF expression for its DW_AT_frame_base. */
441 const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs
=
443 locexpr_find_frame_base_location
,
444 locexpr_get_frame_base
447 /* Implement find_frame_base_location method for LOC_BLOCK functions using
448 DWARF location list for its DW_AT_frame_base. */
451 loclist_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
452 const gdb_byte
**start
, size_t *length
)
454 struct dwarf2_loclist_baton
*symbaton
455 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
457 *start
= dwarf2_find_location_expression (symbaton
, length
, pc
);
460 /* Implement the struct symbol_block_ops::get_frame_base method for
461 LOC_BLOCK functions using a DWARF location list as its DW_AT_frame_base. */
464 loclist_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
466 struct gdbarch
*gdbarch
;
468 struct dwarf2_loclist_baton
*dlbaton
;
469 const gdb_byte
*start
;
471 struct value
*result
;
473 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
474 Thus, it's supposed to provide the find_frame_base_location method as
476 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
478 gdbarch
= get_frame_arch (frame
);
479 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
480 dlbaton
= (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
482 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
483 (framefunc
, get_frame_pc (frame
), &start
, &length
);
484 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
487 /* The DW_AT_frame_base attribute contains a location description which
488 computes the base address itself. However, the call to
489 dwarf2_evaluate_loc_desc returns a value representing a variable at
490 that address. The frame base address is thus this variable's
492 return value_address (result
);
495 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
496 function uses DWARF location list for its DW_AT_frame_base. */
498 const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs
=
500 loclist_find_frame_base_location
,
501 loclist_get_frame_base
504 /* See dwarf2loc.h. */
507 func_get_frame_base_dwarf_block (struct symbol
*framefunc
, CORE_ADDR pc
,
508 const gdb_byte
**start
, size_t *length
)
510 if (SYMBOL_BLOCK_OPS (framefunc
) != NULL
)
512 const struct symbol_block_ops
*ops_block
= SYMBOL_BLOCK_OPS (framefunc
);
514 ops_block
->find_frame_base_location (framefunc
, pc
, start
, length
);
520 error (_("Could not find the frame base for \"%s\"."),
521 SYMBOL_NATURAL_NAME (framefunc
));
525 get_frame_pc_for_per_cu_dwarf_call (void *baton
)
527 dwarf_expr_context
*ctx
= (dwarf_expr_context
*) baton
;
529 return ctx
->get_frame_pc ();
533 per_cu_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
,
534 struct dwarf2_per_cu_data
*per_cu
)
536 struct dwarf2_locexpr_baton block
;
538 block
= dwarf2_fetch_die_loc_cu_off (die_offset
, per_cu
,
539 get_frame_pc_for_per_cu_dwarf_call
,
542 /* DW_OP_call_ref is currently not supported. */
543 gdb_assert (block
.per_cu
== per_cu
);
545 ctx
->eval (block
.data
, block
.size
);
548 class dwarf_evaluate_loc_desc
: public dwarf_expr_context
552 struct frame_info
*frame
;
553 struct dwarf2_per_cu_data
*per_cu
;
554 CORE_ADDR obj_address
;
556 /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for
557 the frame in BATON. */
559 CORE_ADDR
get_frame_cfa () OVERRIDE
561 return dwarf2_frame_cfa (frame
);
564 /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for
565 the frame in BATON. */
567 CORE_ADDR
get_frame_pc () OVERRIDE
569 return get_frame_address_in_block (frame
);
572 /* Using the objfile specified in BATON, find the address for the
573 current thread's thread-local storage with offset OFFSET. */
574 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
576 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
578 return target_translate_tls_address (objfile
, offset
);
581 /* Helper interface of per_cu_dwarf_call for
582 dwarf2_evaluate_loc_desc. */
584 void dwarf_call (cu_offset die_offset
) OVERRIDE
586 per_cu_dwarf_call (this, die_offset
, per_cu
);
589 struct type
*get_base_type (cu_offset die_offset
, int size
) OVERRIDE
591 struct type
*result
= dwarf2_get_die_type (die_offset
, per_cu
);
593 error (_("Could not find type for DW_OP_const_type"));
594 if (size
!= 0 && TYPE_LENGTH (result
) != size
)
595 error (_("DW_OP_const_type has different sizes for type and data"));
599 /* Callback function for dwarf2_evaluate_loc_desc.
600 Fetch the address indexed by DW_OP_GNU_addr_index. */
602 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
604 return dwarf2_read_addr_index (per_cu
, index
);
607 /* Callback function for get_object_address. Return the address of the VLA
610 CORE_ADDR
get_object_address () OVERRIDE
612 if (obj_address
== 0)
613 error (_("Location address is not set."));
617 /* Execute DWARF block of call_site_parameter which matches KIND and
618 KIND_U. Choose DEREF_SIZE value of that parameter. Search
619 caller of this objects's frame.
621 The caller can be from a different CU - per_cu_dwarf_call
622 implementation can be more simple as it does not support cross-CU
625 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
626 union call_site_parameter_u kind_u
,
627 int deref_size
) OVERRIDE
629 struct frame_info
*caller_frame
;
630 struct dwarf2_per_cu_data
*caller_per_cu
;
631 struct call_site_parameter
*parameter
;
632 const gdb_byte
*data_src
;
635 caller_frame
= get_prev_frame (frame
);
637 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
639 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
640 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
642 /* DEREF_SIZE size is not verified here. */
643 if (data_src
== NULL
)
644 throw_error (NO_ENTRY_VALUE_ERROR
,
645 _("Cannot resolve DW_AT_call_data_value"));
647 scoped_restore save_frame
= make_scoped_restore (&this->frame
,
649 scoped_restore save_per_cu
= make_scoped_restore (&this->per_cu
,
651 scoped_restore save_obj_addr
= make_scoped_restore (&this->obj_address
,
654 scoped_restore save_arch
= make_scoped_restore (&this->gdbarch
);
656 = get_objfile_arch (dwarf2_per_cu_objfile (per_cu
));
657 scoped_restore save_addr_size
= make_scoped_restore (&this->addr_size
);
658 this->addr_size
= dwarf2_per_cu_addr_size (per_cu
);
659 scoped_restore save_offset
= make_scoped_restore (&this->offset
);
660 this->offset
= dwarf2_per_cu_text_offset (per_cu
);
662 this->eval (data_src
, size
);
665 /* Using the frame specified in BATON, find the location expression
666 describing the frame base. Return a pointer to it in START and
667 its length in LENGTH. */
668 void get_frame_base (const gdb_byte
**start
, size_t * length
) OVERRIDE
670 /* FIXME: cagney/2003-03-26: This code should be using
671 get_frame_base_address(), and then implement a dwarf2 specific
673 struct symbol
*framefunc
;
674 const struct block
*bl
= get_frame_block (frame
, NULL
);
677 error (_("frame address is not available."));
679 /* Use block_linkage_function, which returns a real (not inlined)
680 function, instead of get_frame_function, which may return an
682 framefunc
= block_linkage_function (bl
);
684 /* If we found a frame-relative symbol then it was certainly within
685 some function associated with a frame. If we can't find the frame,
686 something has gone wrong. */
687 gdb_assert (framefunc
!= NULL
);
689 func_get_frame_base_dwarf_block (framefunc
,
690 get_frame_address_in_block (frame
),
694 /* Read memory at ADDR (length LEN) into BUF. */
696 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
698 read_memory (addr
, buf
, len
);
701 /* Using the frame specified in BATON, return the value of register
702 REGNUM, treated as a pointer. */
703 CORE_ADDR
read_addr_from_reg (int dwarf_regnum
) OVERRIDE
705 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
706 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
708 return address_from_register (regnum
, frame
);
711 /* Implement "get_reg_value" callback. */
713 struct value
*get_reg_value (struct type
*type
, int dwarf_regnum
) OVERRIDE
715 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
716 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
718 return value_from_register (type
, regnum
, frame
);
722 /* See dwarf2loc.h. */
724 unsigned int entry_values_debug
= 0;
726 /* Helper to set entry_values_debug. */
729 show_entry_values_debug (struct ui_file
*file
, int from_tty
,
730 struct cmd_list_element
*c
, const char *value
)
732 fprintf_filtered (file
,
733 _("Entry values and tail call frames debugging is %s.\n"),
737 /* Find DW_TAG_call_site's DW_AT_call_target address.
738 CALLER_FRAME (for registers) can be NULL if it is not known. This function
739 always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */
742 call_site_to_target_addr (struct gdbarch
*call_site_gdbarch
,
743 struct call_site
*call_site
,
744 struct frame_info
*caller_frame
)
746 switch (FIELD_LOC_KIND (call_site
->target
))
748 case FIELD_LOC_KIND_DWARF_BLOCK
:
750 struct dwarf2_locexpr_baton
*dwarf_block
;
752 struct type
*caller_core_addr_type
;
753 struct gdbarch
*caller_arch
;
755 dwarf_block
= FIELD_DWARF_BLOCK (call_site
->target
);
756 if (dwarf_block
== NULL
)
758 struct bound_minimal_symbol msym
;
760 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
761 throw_error (NO_ENTRY_VALUE_ERROR
,
762 _("DW_AT_call_target is not specified at %s in %s"),
763 paddress (call_site_gdbarch
, call_site
->pc
),
764 (msym
.minsym
== NULL
? "???"
765 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
768 if (caller_frame
== NULL
)
770 struct bound_minimal_symbol msym
;
772 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
773 throw_error (NO_ENTRY_VALUE_ERROR
,
774 _("DW_AT_call_target DWARF block resolving "
775 "requires known frame which is currently not "
776 "available at %s in %s"),
777 paddress (call_site_gdbarch
, call_site
->pc
),
778 (msym
.minsym
== NULL
? "???"
779 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
782 caller_arch
= get_frame_arch (caller_frame
);
783 caller_core_addr_type
= builtin_type (caller_arch
)->builtin_func_ptr
;
784 val
= dwarf2_evaluate_loc_desc (caller_core_addr_type
, caller_frame
,
785 dwarf_block
->data
, dwarf_block
->size
,
786 dwarf_block
->per_cu
);
787 /* DW_AT_call_target is a DWARF expression, not a DWARF location. */
788 if (VALUE_LVAL (val
) == lval_memory
)
789 return value_address (val
);
791 return value_as_address (val
);
794 case FIELD_LOC_KIND_PHYSNAME
:
796 const char *physname
;
797 struct bound_minimal_symbol msym
;
799 physname
= FIELD_STATIC_PHYSNAME (call_site
->target
);
801 /* Handle both the mangled and demangled PHYSNAME. */
802 msym
= lookup_minimal_symbol (physname
, NULL
, NULL
);
803 if (msym
.minsym
== NULL
)
805 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
806 throw_error (NO_ENTRY_VALUE_ERROR
,
807 _("Cannot find function \"%s\" for a call site target "
809 physname
, paddress (call_site_gdbarch
, call_site
->pc
),
810 (msym
.minsym
== NULL
? "???"
811 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
814 return BMSYMBOL_VALUE_ADDRESS (msym
);
817 case FIELD_LOC_KIND_PHYSADDR
:
818 return FIELD_STATIC_PHYSADDR (call_site
->target
);
821 internal_error (__FILE__
, __LINE__
, _("invalid call site target kind"));
825 /* Convert function entry point exact address ADDR to the function which is
826 compliant with TAIL_CALL_LIST_COMPLETE condition. Throw
827 NO_ENTRY_VALUE_ERROR otherwise. */
829 static struct symbol
*
830 func_addr_to_tail_call_list (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
832 struct symbol
*sym
= find_pc_function (addr
);
835 if (sym
== NULL
|| BLOCK_START (SYMBOL_BLOCK_VALUE (sym
)) != addr
)
836 throw_error (NO_ENTRY_VALUE_ERROR
,
837 _("DW_TAG_call_site resolving failed to find function "
838 "name for address %s"),
839 paddress (gdbarch
, addr
));
841 type
= SYMBOL_TYPE (sym
);
842 gdb_assert (TYPE_CODE (type
) == TYPE_CODE_FUNC
);
843 gdb_assert (TYPE_SPECIFIC_FIELD (type
) == TYPE_SPECIFIC_FUNC
);
848 /* Verify function with entry point exact address ADDR can never call itself
849 via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it
850 can call itself via tail calls.
852 If a funtion can tail call itself its entry value based parameters are
853 unreliable. There is no verification whether the value of some/all
854 parameters is unchanged through the self tail call, we expect if there is
855 a self tail call all the parameters can be modified. */
858 func_verify_no_selftailcall (struct gdbarch
*gdbarch
, CORE_ADDR verify_addr
)
862 /* The verification is completely unordered. Track here function addresses
863 which still need to be iterated. */
864 std::vector
<CORE_ADDR
> todo
;
866 /* Track here CORE_ADDRs which were already visited. */
867 std::unordered_set
<CORE_ADDR
> addr_hash
;
869 todo
.push_back (verify_addr
);
870 while (!todo
.empty ())
872 struct symbol
*func_sym
;
873 struct call_site
*call_site
;
878 func_sym
= func_addr_to_tail_call_list (gdbarch
, addr
);
880 for (call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym
));
881 call_site
; call_site
= call_site
->tail_call_next
)
883 CORE_ADDR target_addr
;
885 /* CALLER_FRAME with registers is not available for tail-call jumped
887 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
889 if (target_addr
== verify_addr
)
891 struct bound_minimal_symbol msym
;
893 msym
= lookup_minimal_symbol_by_pc (verify_addr
);
894 throw_error (NO_ENTRY_VALUE_ERROR
,
895 _("DW_OP_entry_value resolving has found "
896 "function \"%s\" at %s can call itself via tail "
898 (msym
.minsym
== NULL
? "???"
899 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
900 paddress (gdbarch
, verify_addr
));
903 if (addr_hash
.insert (target_addr
).second
)
904 todo
.push_back (target_addr
);
909 /* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for
910 ENTRY_VALUES_DEBUG. */
913 tailcall_dump (struct gdbarch
*gdbarch
, const struct call_site
*call_site
)
915 CORE_ADDR addr
= call_site
->pc
;
916 struct bound_minimal_symbol msym
= lookup_minimal_symbol_by_pc (addr
- 1);
918 fprintf_unfiltered (gdb_stdlog
, " %s(%s)", paddress (gdbarch
, addr
),
919 (msym
.minsym
== NULL
? "???"
920 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
924 /* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP
925 only top callers and bottom callees which are present in both. GDBARCH is
926 used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are
927 no remaining possibilities to provide unambiguous non-trivial result.
928 RESULTP should point to NULL on the first (initialization) call. Caller is
929 responsible for xfree of any RESULTP data. */
932 chain_candidate (struct gdbarch
*gdbarch
,
933 gdb::unique_xmalloc_ptr
<struct call_site_chain
> *resultp
,
934 std::vector
<struct call_site
*> *chain
)
936 long length
= chain
->size ();
937 int callers
, callees
, idx
;
939 if (*resultp
== NULL
)
941 /* Create the initial chain containing all the passed PCs. */
943 struct call_site_chain
*result
944 = ((struct call_site_chain
*)
945 xmalloc (sizeof (*result
)
946 + sizeof (*result
->call_site
) * (length
- 1)));
947 result
->length
= length
;
948 result
->callers
= result
->callees
= length
;
949 if (!chain
->empty ())
950 memcpy (result
->call_site
, chain
->data (),
951 sizeof (*result
->call_site
) * length
);
952 resultp
->reset (result
);
954 if (entry_values_debug
)
956 fprintf_unfiltered (gdb_stdlog
, "tailcall: initial:");
957 for (idx
= 0; idx
< length
; idx
++)
958 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
959 fputc_unfiltered ('\n', gdb_stdlog
);
965 if (entry_values_debug
)
967 fprintf_unfiltered (gdb_stdlog
, "tailcall: compare:");
968 for (idx
= 0; idx
< length
; idx
++)
969 tailcall_dump (gdbarch
, chain
->at (idx
));
970 fputc_unfiltered ('\n', gdb_stdlog
);
973 /* Intersect callers. */
975 callers
= std::min ((long) (*resultp
)->callers
, length
);
976 for (idx
= 0; idx
< callers
; idx
++)
977 if ((*resultp
)->call_site
[idx
] != chain
->at (idx
))
979 (*resultp
)->callers
= idx
;
983 /* Intersect callees. */
985 callees
= std::min ((long) (*resultp
)->callees
, length
);
986 for (idx
= 0; idx
< callees
; idx
++)
987 if ((*resultp
)->call_site
[(*resultp
)->length
- 1 - idx
]
988 != chain
->at (length
- 1 - idx
))
990 (*resultp
)->callees
= idx
;
994 if (entry_values_debug
)
996 fprintf_unfiltered (gdb_stdlog
, "tailcall: reduced:");
997 for (idx
= 0; idx
< (*resultp
)->callers
; idx
++)
998 tailcall_dump (gdbarch
, (*resultp
)->call_site
[idx
]);
999 fputs_unfiltered (" |", gdb_stdlog
);
1000 for (idx
= 0; idx
< (*resultp
)->callees
; idx
++)
1001 tailcall_dump (gdbarch
,
1002 (*resultp
)->call_site
[(*resultp
)->length
1003 - (*resultp
)->callees
+ idx
]);
1004 fputc_unfiltered ('\n', gdb_stdlog
);
1007 if ((*resultp
)->callers
== 0 && (*resultp
)->callees
== 0)
1009 /* There are no common callers or callees. It could be also a direct
1010 call (which has length 0) with ambiguous possibility of an indirect
1011 call - CALLERS == CALLEES == 0 is valid during the first allocation
1012 but any subsequence processing of such entry means ambiguity. */
1013 resultp
->reset (NULL
);
1017 /* See call_site_find_chain_1 why there is no way to reach the bottom callee
1018 PC again. In such case there must be two different code paths to reach
1019 it. CALLERS + CALLEES equal to LENGTH in the case of self tail-call. */
1020 gdb_assert ((*resultp
)->callers
+ (*resultp
)->callees
<= (*resultp
)->length
);
1023 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1024 assumed frames between them use GDBARCH. Use depth first search so we can
1025 keep single CHAIN of call_site's back to CALLER_PC. Function recursion
1026 would have needless GDB stack overhead. Caller is responsible for xfree of
1027 the returned result. Any unreliability results in thrown
1028 NO_ENTRY_VALUE_ERROR. */
1030 static struct call_site_chain
*
1031 call_site_find_chain_1 (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1032 CORE_ADDR callee_pc
)
1034 CORE_ADDR save_callee_pc
= callee_pc
;
1035 gdb::unique_xmalloc_ptr
<struct call_site_chain
> retval
;
1036 struct call_site
*call_site
;
1038 /* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's
1039 call_site nor any possible call_site at CALLEE_PC's function is there.
1040 Any CALL_SITE in CHAIN will be iterated to its siblings - via
1041 TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */
1042 std::vector
<struct call_site
*> chain
;
1044 /* We are not interested in the specific PC inside the callee function. */
1045 callee_pc
= get_pc_function_start (callee_pc
);
1047 throw_error (NO_ENTRY_VALUE_ERROR
, _("Unable to find function for PC %s"),
1048 paddress (gdbarch
, save_callee_pc
));
1050 /* Mark CALL_SITEs so we do not visit the same ones twice. */
1051 std::unordered_set
<CORE_ADDR
> addr_hash
;
1053 /* Do not push CALL_SITE to CHAIN. Push there only the first tail call site
1054 at the target's function. All the possible tail call sites in the
1055 target's function will get iterated as already pushed into CHAIN via their
1057 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1061 CORE_ADDR target_func_addr
;
1062 struct call_site
*target_call_site
;
1064 /* CALLER_FRAME with registers is not available for tail-call jumped
1066 target_func_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
1068 if (target_func_addr
== callee_pc
)
1070 chain_candidate (gdbarch
, &retval
, &chain
);
1074 /* There is no way to reach CALLEE_PC again as we would prevent
1075 entering it twice as being already marked in ADDR_HASH. */
1076 target_call_site
= NULL
;
1080 struct symbol
*target_func
;
1082 target_func
= func_addr_to_tail_call_list (gdbarch
, target_func_addr
);
1083 target_call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func
));
1088 /* Attempt to visit TARGET_CALL_SITE. */
1090 if (target_call_site
)
1092 if (addr_hash
.insert (target_call_site
->pc
).second
)
1094 /* Successfully entered TARGET_CALL_SITE. */
1096 chain
.push_back (target_call_site
);
1101 /* Backtrack (without revisiting the originating call_site). Try the
1102 callers's sibling; if there isn't any try the callers's callers's
1105 target_call_site
= NULL
;
1106 while (!chain
.empty ())
1108 call_site
= chain
.back ();
1111 size_t removed
= addr_hash
.erase (call_site
->pc
);
1112 gdb_assert (removed
== 1);
1114 target_call_site
= call_site
->tail_call_next
;
1115 if (target_call_site
)
1119 while (target_call_site
);
1124 call_site
= chain
.back ();
1129 struct bound_minimal_symbol msym_caller
, msym_callee
;
1131 msym_caller
= lookup_minimal_symbol_by_pc (caller_pc
);
1132 msym_callee
= lookup_minimal_symbol_by_pc (callee_pc
);
1133 throw_error (NO_ENTRY_VALUE_ERROR
,
1134 _("There are no unambiguously determinable intermediate "
1135 "callers or callees between caller function \"%s\" at %s "
1136 "and callee function \"%s\" at %s"),
1137 (msym_caller
.minsym
== NULL
1138 ? "???" : MSYMBOL_PRINT_NAME (msym_caller
.minsym
)),
1139 paddress (gdbarch
, caller_pc
),
1140 (msym_callee
.minsym
== NULL
1141 ? "???" : MSYMBOL_PRINT_NAME (msym_callee
.minsym
)),
1142 paddress (gdbarch
, callee_pc
));
1145 return retval
.release ();
1148 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1149 assumed frames between them use GDBARCH. If valid call_site_chain cannot be
1150 constructed return NULL. Caller is responsible for xfree of the returned
1153 struct call_site_chain
*
1154 call_site_find_chain (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1155 CORE_ADDR callee_pc
)
1157 struct call_site_chain
*retval
= NULL
;
1161 retval
= call_site_find_chain_1 (gdbarch
, caller_pc
, callee_pc
);
1163 CATCH (e
, RETURN_MASK_ERROR
)
1165 if (e
.error
== NO_ENTRY_VALUE_ERROR
)
1167 if (entry_values_debug
)
1168 exception_print (gdb_stdout
, e
);
1173 throw_exception (e
);
1180 /* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */
1183 call_site_parameter_matches (struct call_site_parameter
*parameter
,
1184 enum call_site_parameter_kind kind
,
1185 union call_site_parameter_u kind_u
)
1187 if (kind
== parameter
->kind
)
1190 case CALL_SITE_PARAMETER_DWARF_REG
:
1191 return kind_u
.dwarf_reg
== parameter
->u
.dwarf_reg
;
1192 case CALL_SITE_PARAMETER_FB_OFFSET
:
1193 return kind_u
.fb_offset
== parameter
->u
.fb_offset
;
1194 case CALL_SITE_PARAMETER_PARAM_OFFSET
:
1195 return kind_u
.param_cu_off
== parameter
->u
.param_cu_off
;
1200 /* Fetch call_site_parameter from caller matching KIND and KIND_U.
1201 FRAME is for callee.
1203 Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
1206 static struct call_site_parameter
*
1207 dwarf_expr_reg_to_entry_parameter (struct frame_info
*frame
,
1208 enum call_site_parameter_kind kind
,
1209 union call_site_parameter_u kind_u
,
1210 struct dwarf2_per_cu_data
**per_cu_return
)
1212 CORE_ADDR func_addr
, caller_pc
;
1213 struct gdbarch
*gdbarch
;
1214 struct frame_info
*caller_frame
;
1215 struct call_site
*call_site
;
1217 /* Initialize it just to avoid a GCC false warning. */
1218 struct call_site_parameter
*parameter
= NULL
;
1219 CORE_ADDR target_addr
;
1221 while (get_frame_type (frame
) == INLINE_FRAME
)
1223 frame
= get_prev_frame (frame
);
1224 gdb_assert (frame
!= NULL
);
1227 func_addr
= get_frame_func (frame
);
1228 gdbarch
= get_frame_arch (frame
);
1229 caller_frame
= get_prev_frame (frame
);
1230 if (gdbarch
!= frame_unwind_arch (frame
))
1232 struct bound_minimal_symbol msym
1233 = lookup_minimal_symbol_by_pc (func_addr
);
1234 struct gdbarch
*caller_gdbarch
= frame_unwind_arch (frame
);
1236 throw_error (NO_ENTRY_VALUE_ERROR
,
1237 _("DW_OP_entry_value resolving callee gdbarch %s "
1238 "(of %s (%s)) does not match caller gdbarch %s"),
1239 gdbarch_bfd_arch_info (gdbarch
)->printable_name
,
1240 paddress (gdbarch
, func_addr
),
1241 (msym
.minsym
== NULL
? "???"
1242 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
1243 gdbarch_bfd_arch_info (caller_gdbarch
)->printable_name
);
1246 if (caller_frame
== NULL
)
1248 struct bound_minimal_symbol msym
1249 = lookup_minimal_symbol_by_pc (func_addr
);
1251 throw_error (NO_ENTRY_VALUE_ERROR
, _("DW_OP_entry_value resolving "
1252 "requires caller of %s (%s)"),
1253 paddress (gdbarch
, func_addr
),
1254 (msym
.minsym
== NULL
? "???"
1255 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
1257 caller_pc
= get_frame_pc (caller_frame
);
1258 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1260 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, caller_frame
);
1261 if (target_addr
!= func_addr
)
1263 struct minimal_symbol
*target_msym
, *func_msym
;
1265 target_msym
= lookup_minimal_symbol_by_pc (target_addr
).minsym
;
1266 func_msym
= lookup_minimal_symbol_by_pc (func_addr
).minsym
;
1267 throw_error (NO_ENTRY_VALUE_ERROR
,
1268 _("DW_OP_entry_value resolving expects callee %s at %s "
1269 "but the called frame is for %s at %s"),
1270 (target_msym
== NULL
? "???"
1271 : MSYMBOL_PRINT_NAME (target_msym
)),
1272 paddress (gdbarch
, target_addr
),
1273 func_msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (func_msym
),
1274 paddress (gdbarch
, func_addr
));
1277 /* No entry value based parameters would be reliable if this function can
1278 call itself via tail calls. */
1279 func_verify_no_selftailcall (gdbarch
, func_addr
);
1281 for (iparams
= 0; iparams
< call_site
->parameter_count
; iparams
++)
1283 parameter
= &call_site
->parameter
[iparams
];
1284 if (call_site_parameter_matches (parameter
, kind
, kind_u
))
1287 if (iparams
== call_site
->parameter_count
)
1289 struct minimal_symbol
*msym
1290 = lookup_minimal_symbol_by_pc (caller_pc
).minsym
;
1292 /* DW_TAG_call_site_parameter will be missing just if GCC could not
1293 determine its value. */
1294 throw_error (NO_ENTRY_VALUE_ERROR
, _("Cannot find matching parameter "
1295 "at DW_TAG_call_site %s at %s"),
1296 paddress (gdbarch
, caller_pc
),
1297 msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (msym
));
1300 *per_cu_return
= call_site
->per_cu
;
1304 /* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return
1305 the normal DW_AT_call_value block. Otherwise return the
1306 DW_AT_call_data_value (dereferenced) block.
1308 TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned
1311 Function always returns non-NULL, non-optimized out value. It throws
1312 NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */
1314 static struct value
*
1315 dwarf_entry_parameter_to_value (struct call_site_parameter
*parameter
,
1316 CORE_ADDR deref_size
, struct type
*type
,
1317 struct frame_info
*caller_frame
,
1318 struct dwarf2_per_cu_data
*per_cu
)
1320 const gdb_byte
*data_src
;
1324 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
1325 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
1327 /* DEREF_SIZE size is not verified here. */
1328 if (data_src
== NULL
)
1329 throw_error (NO_ENTRY_VALUE_ERROR
,
1330 _("Cannot resolve DW_AT_call_data_value"));
1332 /* DW_AT_call_value is a DWARF expression, not a DWARF
1333 location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from
1335 data
= (gdb_byte
*) alloca (size
+ 1);
1336 memcpy (data
, data_src
, size
);
1337 data
[size
] = DW_OP_stack_value
;
1339 return dwarf2_evaluate_loc_desc (type
, caller_frame
, data
, size
+ 1, per_cu
);
1342 /* VALUE must be of type lval_computed with entry_data_value_funcs. Perform
1343 the indirect method on it, that is use its stored target value, the sole
1344 purpose of entry_data_value_funcs.. */
1346 static struct value
*
1347 entry_data_value_coerce_ref (const struct value
*value
)
1349 struct type
*checked_type
= check_typedef (value_type (value
));
1350 struct value
*target_val
;
1352 if (!TYPE_IS_REFERENCE (checked_type
))
1355 target_val
= (struct value
*) value_computed_closure (value
);
1356 value_incref (target_val
);
1360 /* Implement copy_closure. */
1363 entry_data_value_copy_closure (const struct value
*v
)
1365 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1367 value_incref (target_val
);
1371 /* Implement free_closure. */
1374 entry_data_value_free_closure (struct value
*v
)
1376 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1378 value_free (target_val
);
1381 /* Vector for methods for an entry value reference where the referenced value
1382 is stored in the caller. On the first dereference use
1383 DW_AT_call_data_value in the caller. */
1385 static const struct lval_funcs entry_data_value_funcs
=
1389 NULL
, /* indirect */
1390 entry_data_value_coerce_ref
,
1391 NULL
, /* check_synthetic_pointer */
1392 entry_data_value_copy_closure
,
1393 entry_data_value_free_closure
1396 /* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U
1397 are used to match DW_AT_location at the caller's
1398 DW_TAG_call_site_parameter.
1400 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1401 cannot resolve the parameter for any reason. */
1403 static struct value
*
1404 value_of_dwarf_reg_entry (struct type
*type
, struct frame_info
*frame
,
1405 enum call_site_parameter_kind kind
,
1406 union call_site_parameter_u kind_u
)
1408 struct type
*checked_type
= check_typedef (type
);
1409 struct type
*target_type
= TYPE_TARGET_TYPE (checked_type
);
1410 struct frame_info
*caller_frame
= get_prev_frame (frame
);
1411 struct value
*outer_val
, *target_val
, *val
;
1412 struct call_site_parameter
*parameter
;
1413 struct dwarf2_per_cu_data
*caller_per_cu
;
1415 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
1418 outer_val
= dwarf_entry_parameter_to_value (parameter
, -1 /* deref_size */,
1422 /* Check if DW_AT_call_data_value cannot be used. If it should be
1423 used and it is not available do not fall back to OUTER_VAL - dereferencing
1424 TYPE_CODE_REF with non-entry data value would give current value - not the
1427 if (!TYPE_IS_REFERENCE (checked_type
)
1428 || TYPE_TARGET_TYPE (checked_type
) == NULL
)
1431 target_val
= dwarf_entry_parameter_to_value (parameter
,
1432 TYPE_LENGTH (target_type
),
1433 target_type
, caller_frame
,
1436 release_value (target_val
);
1437 val
= allocate_computed_value (type
, &entry_data_value_funcs
,
1438 target_val
/* closure */);
1440 /* Copy the referencing pointer to the new computed value. */
1441 memcpy (value_contents_raw (val
), value_contents_raw (outer_val
),
1442 TYPE_LENGTH (checked_type
));
1443 set_value_lazy (val
, 0);
1448 /* Read parameter of TYPE at (callee) FRAME's function entry. DATA and
1449 SIZE are DWARF block used to match DW_AT_location at the caller's
1450 DW_TAG_call_site_parameter.
1452 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1453 cannot resolve the parameter for any reason. */
1455 static struct value
*
1456 value_of_dwarf_block_entry (struct type
*type
, struct frame_info
*frame
,
1457 const gdb_byte
*block
, size_t block_len
)
1459 union call_site_parameter_u kind_u
;
1461 kind_u
.dwarf_reg
= dwarf_block_to_dwarf_reg (block
, block
+ block_len
);
1462 if (kind_u
.dwarf_reg
!= -1)
1463 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_DWARF_REG
,
1466 if (dwarf_block_to_fb_offset (block
, block
+ block_len
, &kind_u
.fb_offset
))
1467 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_FB_OFFSET
,
1470 /* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message
1471 suppressed during normal operation. The expression can be arbitrary if
1472 there is no caller-callee entry value binding expected. */
1473 throw_error (NO_ENTRY_VALUE_ERROR
,
1474 _("DWARF-2 expression error: DW_OP_entry_value is supported "
1475 "only for single DW_OP_reg* or for DW_OP_fbreg(*)"));
1478 struct piece_closure
1480 /* Reference count. */
1483 /* The CU from which this closure's expression came. */
1484 struct dwarf2_per_cu_data
*per_cu
;
1486 /* The number of pieces used to describe this variable. */
1489 /* The pieces themselves. */
1490 struct dwarf_expr_piece
*pieces
;
1492 /* Frame ID of frame to which a register value is relative, used
1493 only by DWARF_VALUE_REGISTER. */
1494 struct frame_id frame_id
;
1497 /* Allocate a closure for a value formed from separately-described
1500 static struct piece_closure
*
1501 allocate_piece_closure (struct dwarf2_per_cu_data
*per_cu
,
1502 int n_pieces
, struct dwarf_expr_piece
*pieces
,
1503 struct frame_info
*frame
)
1505 struct piece_closure
*c
= XCNEW (struct piece_closure
);
1510 c
->n_pieces
= n_pieces
;
1511 c
->pieces
= XCNEWVEC (struct dwarf_expr_piece
, n_pieces
);
1513 c
->frame_id
= null_frame_id
;
1515 c
->frame_id
= get_frame_id (frame
);
1517 memcpy (c
->pieces
, pieces
, n_pieces
* sizeof (struct dwarf_expr_piece
));
1518 for (i
= 0; i
< n_pieces
; ++i
)
1519 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
1520 value_incref (c
->pieces
[i
].v
.value
);
1525 /* Copy NBITS bits from SOURCE to DEST starting at the given bit
1526 offsets. Use the bit order as specified by BITS_BIG_ENDIAN.
1527 Source and destination buffers must not overlap. */
1530 copy_bitwise (gdb_byte
*dest
, ULONGEST dest_offset
,
1531 const gdb_byte
*source
, ULONGEST source_offset
,
1532 ULONGEST nbits
, int bits_big_endian
)
1534 unsigned int buf
, avail
;
1539 if (bits_big_endian
)
1541 /* Start from the end, then work backwards. */
1542 dest_offset
+= nbits
- 1;
1543 dest
+= dest_offset
/ 8;
1544 dest_offset
= 7 - dest_offset
% 8;
1545 source_offset
+= nbits
- 1;
1546 source
+= source_offset
/ 8;
1547 source_offset
= 7 - source_offset
% 8;
1551 dest
+= dest_offset
/ 8;
1553 source
+= source_offset
/ 8;
1557 /* Fill BUF with DEST_OFFSET bits from the destination and 8 -
1558 SOURCE_OFFSET bits from the source. */
1559 buf
= *(bits_big_endian
? source
-- : source
++) >> source_offset
;
1560 buf
<<= dest_offset
;
1561 buf
|= *dest
& ((1 << dest_offset
) - 1);
1563 /* NBITS: bits yet to be written; AVAIL: BUF's fill level. */
1564 nbits
+= dest_offset
;
1565 avail
= dest_offset
+ 8 - source_offset
;
1567 /* Flush 8 bits from BUF, if appropriate. */
1568 if (nbits
>= 8 && avail
>= 8)
1570 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1576 /* Copy the middle part. */
1579 size_t len
= nbits
/ 8;
1581 /* Use a faster method for byte-aligned copies. */
1584 if (bits_big_endian
)
1588 memcpy (dest
+ 1, source
+ 1, len
);
1592 memcpy (dest
, source
, len
);
1601 buf
|= *(bits_big_endian
? source
-- : source
++) << avail
;
1602 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1609 /* Write the last byte. */
1613 buf
|= *source
<< avail
;
1615 buf
&= (1 << nbits
) - 1;
1616 *dest
= (*dest
& (~0 << nbits
)) | buf
;
1622 namespace selftests
{
1624 /* Helper function for the unit test of copy_bitwise. Convert NBITS bits
1625 out of BITS, starting at OFFS, to the respective '0'/'1'-string. MSB0
1626 specifies whether to assume big endian bit numbering. Store the
1627 resulting (not null-terminated) string at STR. */
1630 bits_to_str (char *str
, const gdb_byte
*bits
, ULONGEST offs
,
1631 ULONGEST nbits
, int msb0
)
1636 for (i
= offs
/ 8, j
= offs
% 8; nbits
; i
++, j
= 0)
1638 unsigned int ch
= bits
[i
];
1639 for (; j
< 8 && nbits
; j
++, nbits
--)
1640 *str
++ = (ch
& (msb0
? (1 << (7 - j
)) : (1 << j
))) ? '1' : '0';
1644 /* Check one invocation of copy_bitwise with the given parameters. */
1647 check_copy_bitwise (const gdb_byte
*dest
, unsigned int dest_offset
,
1648 const gdb_byte
*source
, unsigned int source_offset
,
1649 unsigned int nbits
, int msb0
)
1651 size_t len
= align_up (dest_offset
+ nbits
, 8);
1652 char *expected
= (char *) alloca (len
+ 1);
1653 char *actual
= (char *) alloca (len
+ 1);
1654 gdb_byte
*buf
= (gdb_byte
*) alloca (len
/ 8);
1656 /* Compose a '0'/'1'-string that represents the expected result of
1658 Bits from [0, DEST_OFFSET) are filled from DEST.
1659 Bits from [DEST_OFFSET, DEST_OFFSET + NBITS) are filled from SOURCE.
1660 Bits from [DEST_OFFSET + NBITS, LEN) are filled from DEST.
1669 We should end up with:
1671 DDDDSSDD (D=dest, S=source)
1673 bits_to_str (expected
, dest
, 0, len
, msb0
);
1674 bits_to_str (expected
+ dest_offset
, source
, source_offset
, nbits
, msb0
);
1676 /* Fill BUF with data from DEST, apply copy_bitwise, and convert the
1677 result to a '0'/'1'-string. */
1678 memcpy (buf
, dest
, len
/ 8);
1679 copy_bitwise (buf
, dest_offset
, source
, source_offset
, nbits
, msb0
);
1680 bits_to_str (actual
, buf
, 0, len
, msb0
);
1682 /* Compare the resulting strings. */
1683 expected
[len
] = actual
[len
] = '\0';
1684 if (strcmp (expected
, actual
) != 0)
1685 error (_("copy_bitwise %s != %s (%u+%u -> %u)"),
1686 expected
, actual
, source_offset
, nbits
, dest_offset
);
1689 /* Unit test for copy_bitwise. */
1692 copy_bitwise_tests (void)
1694 /* Data to be used as both source and destination buffers. The two
1695 arrays below represent the lsb0- and msb0- encoded versions of the
1696 following bit string, respectively:
1697 00000000 00011111 11111111 01001000 10100101 11110010
1698 This pattern is chosen such that it contains:
1699 - constant 0- and 1- chunks of more than a full byte;
1700 - 0/1- and 1/0 transitions on all bit positions within a byte;
1701 - several sufficiently asymmetric bytes.
1703 static const gdb_byte data_lsb0
[] = {
1704 0x00, 0xf8, 0xff, 0x12, 0xa5, 0x4f
1706 static const gdb_byte data_msb0
[] = {
1707 0x00, 0x1f, 0xff, 0x48, 0xa5, 0xf2
1710 constexpr size_t data_nbits
= 8 * sizeof (data_lsb0
);
1711 constexpr unsigned max_nbits
= 24;
1713 /* Try all combinations of:
1714 lsb0/msb0 bit order (using the respective data array)
1715 X [0, MAX_NBITS] copy bit width
1716 X feasible source offsets for the given copy bit width
1717 X feasible destination offsets
1719 for (int msb0
= 0; msb0
< 2; msb0
++)
1721 const gdb_byte
*data
= msb0
? data_msb0
: data_lsb0
;
1723 for (unsigned int nbits
= 1; nbits
<= max_nbits
; nbits
++)
1725 const unsigned int max_offset
= data_nbits
- nbits
;
1727 for (unsigned source_offset
= 0;
1728 source_offset
<= max_offset
;
1731 for (unsigned dest_offset
= 0;
1732 dest_offset
<= max_offset
;
1735 check_copy_bitwise (data
+ dest_offset
/ 8,
1737 data
+ source_offset
/ 8,
1744 /* Special cases: copy all, copy nothing. */
1745 check_copy_bitwise (data_lsb0
, 0, data_msb0
, 0, data_nbits
, msb0
);
1746 check_copy_bitwise (data_msb0
, 0, data_lsb0
, 0, data_nbits
, msb0
);
1747 check_copy_bitwise (data
, data_nbits
- 7, data
, 9, 0, msb0
);
1751 } /* namespace selftests */
1753 #endif /* GDB_SELF_TEST */
1755 /* Return the number of bytes overlapping a contiguous chunk of N_BITS
1756 bits whose first bit is located at bit offset START. */
1759 bits_to_bytes (ULONGEST start
, ULONGEST n_bits
)
1761 return (start
% 8 + n_bits
+ 7) / 8;
1765 read_pieced_value (struct value
*v
)
1768 LONGEST offset
= 0, max_offset
;
1769 ULONGEST bits_to_skip
;
1771 struct piece_closure
*c
1772 = (struct piece_closure
*) value_computed_closure (v
);
1773 std::vector
<gdb_byte
> buffer
;
1775 = gdbarch_bits_big_endian (get_type_arch (value_type (v
)));
1777 if (value_type (v
) != value_enclosing_type (v
))
1778 internal_error (__FILE__
, __LINE__
,
1779 _("Should not be able to create a lazy value with "
1780 "an enclosing type"));
1782 contents
= value_contents_raw (v
);
1783 bits_to_skip
= 8 * value_offset (v
);
1784 if (value_bitsize (v
))
1786 bits_to_skip
+= (8 * value_offset (value_parent (v
))
1787 + value_bitpos (v
));
1788 max_offset
= value_bitsize (v
);
1791 max_offset
= 8 * TYPE_LENGTH (value_type (v
));
1793 for (i
= 0; i
< c
->n_pieces
&& offset
< max_offset
; i
++)
1795 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1796 size_t this_size
, this_size_bits
;
1797 long dest_offset_bits
, source_offset_bits
;
1799 /* Compute size, source, and destination offsets for copying, in
1801 this_size_bits
= p
->size
;
1802 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1804 bits_to_skip
-= this_size_bits
;
1807 source_offset_bits
= bits_to_skip
;
1808 this_size_bits
-= bits_to_skip
;
1810 dest_offset_bits
= offset
;
1812 if (this_size_bits
> max_offset
- offset
)
1813 this_size_bits
= max_offset
- offset
;
1815 /* Copy from the source to DEST_BUFFER. */
1816 switch (p
->location
)
1818 case DWARF_VALUE_REGISTER
:
1820 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1821 struct gdbarch
*arch
= get_frame_arch (frame
);
1822 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1823 ULONGEST reg_bits
= 8 * register_size (arch
, gdb_regnum
);
1826 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1827 && p
->size
< reg_bits
)
1829 /* Big-endian, and we want less than full size. */
1830 source_offset_bits
+= reg_bits
- p
->size
;
1832 this_size
= bits_to_bytes (source_offset_bits
, this_size_bits
);
1833 buffer
.reserve (this_size
);
1835 if (!get_frame_register_bytes (frame
, gdb_regnum
,
1836 source_offset_bits
/ 8,
1837 this_size
, buffer
.data (),
1841 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1843 mark_value_bits_unavailable (v
, offset
, this_size_bits
);
1847 copy_bitwise (contents
, dest_offset_bits
,
1848 buffer
.data (), source_offset_bits
% 8,
1849 this_size_bits
, bits_big_endian
);
1853 case DWARF_VALUE_MEMORY
:
1854 this_size
= bits_to_bytes (source_offset_bits
, this_size_bits
);
1855 buffer
.reserve (this_size
);
1857 read_value_memory (v
, offset
,
1858 p
->v
.mem
.in_stack_memory
,
1859 p
->v
.mem
.addr
+ source_offset_bits
/ 8,
1860 buffer
.data (), this_size
);
1861 copy_bitwise (contents
, dest_offset_bits
,
1862 buffer
.data (), source_offset_bits
% 8,
1863 this_size_bits
, bits_big_endian
);
1866 case DWARF_VALUE_STACK
:
1868 struct objfile
*objfile
= dwarf2_per_cu_objfile (c
->per_cu
);
1869 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
1870 ULONGEST stack_value_size_bits
1871 = 8 * TYPE_LENGTH (value_type (p
->v
.value
));
1873 /* Use zeroes if piece reaches beyond stack value. */
1874 if (p
->size
> stack_value_size_bits
)
1877 /* Piece is anchored at least significant bit end. */
1878 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
1879 source_offset_bits
+= stack_value_size_bits
- p
->size
;
1881 copy_bitwise (contents
, dest_offset_bits
,
1882 value_contents_all (p
->v
.value
),
1884 this_size_bits
, bits_big_endian
);
1888 case DWARF_VALUE_LITERAL
:
1890 ULONGEST literal_size_bits
= 8 * p
->v
.literal
.length
;
1891 size_t n
= this_size_bits
;
1893 /* Cut off at the end of the implicit value. */
1894 if (source_offset_bits
>= literal_size_bits
)
1896 if (n
> literal_size_bits
- source_offset_bits
)
1897 n
= literal_size_bits
- source_offset_bits
;
1899 copy_bitwise (contents
, dest_offset_bits
,
1900 p
->v
.literal
.data
, source_offset_bits
,
1901 n
, bits_big_endian
);
1905 /* These bits show up as zeros -- but do not cause the value
1906 to be considered optimized-out. */
1907 case DWARF_VALUE_IMPLICIT_POINTER
:
1910 case DWARF_VALUE_OPTIMIZED_OUT
:
1911 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1915 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
1918 offset
+= this_size_bits
;
1923 write_pieced_value (struct value
*to
, struct value
*from
)
1926 ULONGEST bits_to_skip
;
1927 LONGEST offset
= 0, max_offset
;
1928 const gdb_byte
*contents
;
1929 struct piece_closure
*c
1930 = (struct piece_closure
*) value_computed_closure (to
);
1931 std::vector
<gdb_byte
> buffer
;
1933 = gdbarch_bits_big_endian (get_type_arch (value_type (to
)));
1935 contents
= value_contents (from
);
1936 bits_to_skip
= 8 * value_offset (to
);
1937 if (value_bitsize (to
))
1939 bits_to_skip
+= (8 * value_offset (value_parent (to
))
1940 + value_bitpos (to
));
1941 /* Use the least significant bits of FROM. */
1942 if (gdbarch_byte_order (get_type_arch (value_type (from
)))
1945 max_offset
= 8 * TYPE_LENGTH (value_type (from
));
1946 offset
= max_offset
- value_bitsize (to
);
1949 max_offset
= value_bitsize (to
);
1952 max_offset
= 8 * TYPE_LENGTH (value_type (to
));
1954 for (i
= 0; i
< c
->n_pieces
&& offset
< max_offset
; i
++)
1956 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1957 size_t this_size_bits
, this_size
;
1958 long dest_offset_bits
, source_offset_bits
;
1960 this_size_bits
= p
->size
;
1961 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1963 bits_to_skip
-= this_size_bits
;
1966 dest_offset_bits
= bits_to_skip
;
1967 this_size_bits
-= bits_to_skip
;
1969 source_offset_bits
= offset
;
1971 if (this_size_bits
> max_offset
- offset
)
1972 this_size_bits
= max_offset
- offset
;
1974 switch (p
->location
)
1976 case DWARF_VALUE_REGISTER
:
1978 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1979 struct gdbarch
*arch
= get_frame_arch (frame
);
1980 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1981 ULONGEST reg_bits
= 8 * register_size (arch
, gdb_regnum
);
1983 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1984 && p
->size
<= reg_bits
)
1986 /* Big-endian, and we want less than full size. */
1987 dest_offset_bits
+= reg_bits
- p
->size
;
1989 this_size
= bits_to_bytes (dest_offset_bits
, this_size_bits
);
1990 buffer
.reserve (this_size
);
1992 if (dest_offset_bits
% 8 != 0 || this_size_bits
% 8 != 0)
1994 /* Data is copied non-byte-aligned into the register.
1995 Need some bits from original register value. */
1998 if (!get_frame_register_bytes (frame
, gdb_regnum
,
1999 dest_offset_bits
/ 8,
2000 this_size
, buffer
.data (),
2004 throw_error (OPTIMIZED_OUT_ERROR
,
2005 _("Can't do read-modify-write to "
2006 "update bitfield; containing word "
2007 "has been optimized out"));
2009 throw_error (NOT_AVAILABLE_ERROR
,
2010 _("Can't do read-modify-write to update "
2011 "bitfield; containing word "
2016 copy_bitwise (buffer
.data (), dest_offset_bits
% 8,
2017 contents
, source_offset_bits
,
2018 this_size_bits
, bits_big_endian
);
2019 put_frame_register_bytes (frame
, gdb_regnum
,
2020 dest_offset_bits
/ 8,
2021 this_size
, buffer
.data ());
2024 case DWARF_VALUE_MEMORY
:
2026 CORE_ADDR start_addr
= p
->v
.mem
.addr
+ dest_offset_bits
/ 8;
2028 if (dest_offset_bits
% 8 == 0 && this_size_bits
% 8 == 0
2029 && source_offset_bits
% 8 == 0)
2031 /* Everything is byte-aligned; no buffer needed. */
2032 write_memory (start_addr
,
2033 contents
+ source_offset_bits
/ 8,
2034 this_size_bits
/ 8);
2038 this_size
= bits_to_bytes (dest_offset_bits
, this_size_bits
);
2039 buffer
.reserve (this_size
);
2041 if (dest_offset_bits
% 8 != 0 || this_size_bits
% 8 != 0)
2045 /* Perform a single read for small sizes. */
2046 read_memory (start_addr
, buffer
.data (), this_size
);
2050 /* Only the first and last bytes can possibly have any
2052 read_memory (start_addr
, buffer
.data (), 1);
2053 read_memory (start_addr
+ this_size
- 1,
2054 &buffer
[this_size
- 1], 1);
2058 copy_bitwise (buffer
.data (), dest_offset_bits
% 8,
2059 contents
, source_offset_bits
,
2060 this_size_bits
, bits_big_endian
);
2061 write_memory (start_addr
, buffer
.data (), this_size
);
2065 mark_value_bytes_optimized_out (to
, 0, TYPE_LENGTH (value_type (to
)));
2068 offset
+= this_size_bits
;
2072 /* An implementation of an lval_funcs method to see whether a value is
2073 a synthetic pointer. */
2076 check_pieced_synthetic_pointer (const struct value
*value
, LONGEST bit_offset
,
2079 struct piece_closure
*c
2080 = (struct piece_closure
*) value_computed_closure (value
);
2083 bit_offset
+= 8 * value_offset (value
);
2084 if (value_bitsize (value
))
2085 bit_offset
+= value_bitpos (value
);
2087 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2089 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2090 size_t this_size_bits
= p
->size
;
2094 if (bit_offset
>= this_size_bits
)
2096 bit_offset
-= this_size_bits
;
2100 bit_length
-= this_size_bits
- bit_offset
;
2104 bit_length
-= this_size_bits
;
2106 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2113 /* A wrapper function for get_frame_address_in_block. */
2116 get_frame_address_in_block_wrapper (void *baton
)
2118 return get_frame_address_in_block ((struct frame_info
*) baton
);
2121 /* Fetch a DW_AT_const_value through a synthetic pointer. */
2123 static struct value
*
2124 fetch_const_value_from_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2125 struct dwarf2_per_cu_data
*per_cu
,
2128 struct value
*result
= NULL
;
2129 struct obstack temp_obstack
;
2130 struct cleanup
*cleanup
;
2131 const gdb_byte
*bytes
;
2134 obstack_init (&temp_obstack
);
2135 cleanup
= make_cleanup_obstack_free (&temp_obstack
);
2136 bytes
= dwarf2_fetch_constant_bytes (die
, per_cu
, &temp_obstack
, &len
);
2140 if (byte_offset
>= 0
2141 && byte_offset
+ TYPE_LENGTH (TYPE_TARGET_TYPE (type
)) <= len
)
2143 bytes
+= byte_offset
;
2144 result
= value_from_contents (TYPE_TARGET_TYPE (type
), bytes
);
2147 invalid_synthetic_pointer ();
2150 result
= allocate_optimized_out_value (TYPE_TARGET_TYPE (type
));
2152 do_cleanups (cleanup
);
2157 /* Fetch the value pointed to by a synthetic pointer. */
2159 static struct value
*
2160 indirect_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2161 struct dwarf2_per_cu_data
*per_cu
,
2162 struct frame_info
*frame
, struct type
*type
)
2164 /* Fetch the location expression of the DIE we're pointing to. */
2165 struct dwarf2_locexpr_baton baton
2166 = dwarf2_fetch_die_loc_sect_off (die
, per_cu
,
2167 get_frame_address_in_block_wrapper
, frame
);
2169 /* Get type of pointed-to DIE. */
2170 struct type
*orig_type
= dwarf2_fetch_die_type_sect_off (die
, per_cu
);
2171 if (orig_type
== NULL
)
2172 invalid_synthetic_pointer ();
2174 /* If pointed-to DIE has a DW_AT_location, evaluate it and return the
2175 resulting value. Otherwise, it may have a DW_AT_const_value instead,
2176 or it may've been optimized out. */
2177 if (baton
.data
!= NULL
)
2178 return dwarf2_evaluate_loc_desc_full (orig_type
, frame
, baton
.data
,
2179 baton
.size
, baton
.per_cu
,
2180 TYPE_TARGET_TYPE (type
),
2183 return fetch_const_value_from_synthetic_pointer (die
, byte_offset
, per_cu
,
2187 /* An implementation of an lval_funcs method to indirect through a
2188 pointer. This handles the synthetic pointer case when needed. */
2190 static struct value
*
2191 indirect_pieced_value (struct value
*value
)
2193 struct piece_closure
*c
2194 = (struct piece_closure
*) value_computed_closure (value
);
2196 struct frame_info
*frame
;
2197 struct dwarf2_locexpr_baton baton
;
2200 struct dwarf_expr_piece
*piece
= NULL
;
2201 LONGEST byte_offset
;
2202 enum bfd_endian byte_order
;
2204 type
= check_typedef (value_type (value
));
2205 if (TYPE_CODE (type
) != TYPE_CODE_PTR
)
2208 bit_length
= 8 * TYPE_LENGTH (type
);
2209 bit_offset
= 8 * value_offset (value
);
2210 if (value_bitsize (value
))
2211 bit_offset
+= value_bitpos (value
);
2213 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2215 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2216 size_t this_size_bits
= p
->size
;
2220 if (bit_offset
>= this_size_bits
)
2222 bit_offset
-= this_size_bits
;
2226 bit_length
-= this_size_bits
- bit_offset
;
2230 bit_length
-= this_size_bits
;
2232 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2235 if (bit_length
!= 0)
2236 error (_("Invalid use of DW_OP_implicit_pointer"));
2242 gdb_assert (piece
!= NULL
);
2243 frame
= get_selected_frame (_("No frame selected."));
2245 /* This is an offset requested by GDB, such as value subscripts.
2246 However, due to how synthetic pointers are implemented, this is
2247 always presented to us as a pointer type. This means we have to
2248 sign-extend it manually as appropriate. Use raw
2249 extract_signed_integer directly rather than value_as_address and
2250 sign extend afterwards on architectures that would need it
2251 (mostly everywhere except MIPS, which has signed addresses) as
2252 the later would go through gdbarch_pointer_to_address and thus
2253 return a CORE_ADDR with high bits set on architectures that
2254 encode address spaces and other things in CORE_ADDR. */
2255 byte_order
= gdbarch_byte_order (get_frame_arch (frame
));
2256 byte_offset
= extract_signed_integer (value_contents (value
),
2257 TYPE_LENGTH (type
), byte_order
);
2258 byte_offset
+= piece
->v
.ptr
.offset
;
2260 return indirect_synthetic_pointer (piece
->v
.ptr
.die_sect_off
,
2261 byte_offset
, c
->per_cu
,
2265 /* Implementation of the coerce_ref method of lval_funcs for synthetic C++
2268 static struct value
*
2269 coerce_pieced_ref (const struct value
*value
)
2271 struct type
*type
= check_typedef (value_type (value
));
2273 if (value_bits_synthetic_pointer (value
, value_embedded_offset (value
),
2274 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
2276 const struct piece_closure
*closure
2277 = (struct piece_closure
*) value_computed_closure (value
);
2278 struct frame_info
*frame
2279 = get_selected_frame (_("No frame selected."));
2281 /* gdb represents synthetic pointers as pieced values with a single
2283 gdb_assert (closure
!= NULL
);
2284 gdb_assert (closure
->n_pieces
== 1);
2286 return indirect_synthetic_pointer (closure
->pieces
->v
.ptr
.die_sect_off
,
2287 closure
->pieces
->v
.ptr
.offset
,
2288 closure
->per_cu
, frame
, type
);
2292 /* Else: not a synthetic reference; do nothing. */
2298 copy_pieced_value_closure (const struct value
*v
)
2300 struct piece_closure
*c
2301 = (struct piece_closure
*) value_computed_closure (v
);
2308 free_pieced_value_closure (struct value
*v
)
2310 struct piece_closure
*c
2311 = (struct piece_closure
*) value_computed_closure (v
);
2318 for (i
= 0; i
< c
->n_pieces
; ++i
)
2319 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
2320 value_free (c
->pieces
[i
].v
.value
);
2327 /* Functions for accessing a variable described by DW_OP_piece. */
2328 static const struct lval_funcs pieced_value_funcs
= {
2331 indirect_pieced_value
,
2333 check_pieced_synthetic_pointer
,
2334 copy_pieced_value_closure
,
2335 free_pieced_value_closure
2338 /* Evaluate a location description, starting at DATA and with length
2339 SIZE, to find the current location of variable of TYPE in the
2340 context of FRAME. If SUBOBJ_TYPE is non-NULL, return instead the
2341 location of the subobject of type SUBOBJ_TYPE at byte offset
2342 SUBOBJ_BYTE_OFFSET within the variable of type TYPE. */
2344 static struct value
*
2345 dwarf2_evaluate_loc_desc_full (struct type
*type
, struct frame_info
*frame
,
2346 const gdb_byte
*data
, size_t size
,
2347 struct dwarf2_per_cu_data
*per_cu
,
2348 struct type
*subobj_type
,
2349 LONGEST subobj_byte_offset
)
2351 struct value
*retval
;
2352 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2354 if (subobj_type
== NULL
)
2357 subobj_byte_offset
= 0;
2359 else if (subobj_byte_offset
< 0)
2360 invalid_synthetic_pointer ();
2363 return allocate_optimized_out_value (subobj_type
);
2365 dwarf_evaluate_loc_desc ctx
;
2367 ctx
.per_cu
= per_cu
;
2368 ctx
.obj_address
= 0;
2370 scoped_value_mark free_values
;
2372 ctx
.gdbarch
= get_objfile_arch (objfile
);
2373 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2374 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2375 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2379 ctx
.eval (data
, size
);
2381 CATCH (ex
, RETURN_MASK_ERROR
)
2383 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2385 free_values
.free_to_mark ();
2386 retval
= allocate_value (subobj_type
);
2387 mark_value_bytes_unavailable (retval
, 0,
2388 TYPE_LENGTH (subobj_type
));
2391 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2393 if (entry_values_debug
)
2394 exception_print (gdb_stdout
, ex
);
2395 free_values
.free_to_mark ();
2396 return allocate_optimized_out_value (subobj_type
);
2399 throw_exception (ex
);
2403 if (ctx
.num_pieces
> 0)
2405 struct piece_closure
*c
;
2406 ULONGEST bit_size
= 0;
2409 for (i
= 0; i
< ctx
.num_pieces
; ++i
)
2410 bit_size
+= ctx
.pieces
[i
].size
;
2411 if (8 * (subobj_byte_offset
+ TYPE_LENGTH (subobj_type
)) > bit_size
)
2412 invalid_synthetic_pointer ();
2414 c
= allocate_piece_closure (per_cu
, ctx
.num_pieces
, ctx
.pieces
,
2416 /* We must clean up the value chain after creating the piece
2417 closure but before allocating the result. */
2418 free_values
.free_to_mark ();
2419 retval
= allocate_computed_value (subobj_type
,
2420 &pieced_value_funcs
, c
);
2421 set_value_offset (retval
, subobj_byte_offset
);
2425 switch (ctx
.location
)
2427 case DWARF_VALUE_REGISTER
:
2429 struct gdbarch
*arch
= get_frame_arch (frame
);
2431 = longest_to_int (value_as_long (ctx
.fetch (0)));
2432 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, dwarf_regnum
);
2434 if (subobj_byte_offset
!= 0)
2435 error (_("cannot use offset on synthetic pointer to register"));
2436 free_values
.free_to_mark ();
2437 retval
= value_from_register (subobj_type
, gdb_regnum
, frame
);
2438 if (value_optimized_out (retval
))
2442 /* This means the register has undefined value / was
2443 not saved. As we're computing the location of some
2444 variable etc. in the program, not a value for
2445 inspecting a register ($pc, $sp, etc.), return a
2446 generic optimized out value instead, so that we show
2447 <optimized out> instead of <not saved>. */
2448 tmp
= allocate_value (subobj_type
);
2449 value_contents_copy (tmp
, 0, retval
, 0,
2450 TYPE_LENGTH (subobj_type
));
2456 case DWARF_VALUE_MEMORY
:
2458 struct type
*ptr_type
;
2459 CORE_ADDR address
= ctx
.fetch_address (0);
2460 int in_stack_memory
= ctx
.fetch_in_stack_memory (0);
2462 /* DW_OP_deref_size (and possibly other operations too) may
2463 create a pointer instead of an address. Ideally, the
2464 pointer to address conversion would be performed as part
2465 of those operations, but the type of the object to
2466 which the address refers is not known at the time of
2467 the operation. Therefore, we do the conversion here
2468 since the type is readily available. */
2470 switch (TYPE_CODE (subobj_type
))
2472 case TYPE_CODE_FUNC
:
2473 case TYPE_CODE_METHOD
:
2474 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_func_ptr
;
2477 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_data_ptr
;
2480 address
= value_as_address (value_from_pointer (ptr_type
, address
));
2482 free_values
.free_to_mark ();
2483 retval
= value_at_lazy (subobj_type
,
2484 address
+ subobj_byte_offset
);
2485 if (in_stack_memory
)
2486 set_value_stack (retval
, 1);
2490 case DWARF_VALUE_STACK
:
2492 struct value
*value
= ctx
.fetch (0);
2493 size_t n
= TYPE_LENGTH (value_type (value
));
2494 size_t len
= TYPE_LENGTH (subobj_type
);
2495 size_t max
= TYPE_LENGTH (type
);
2496 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2497 struct cleanup
*cleanup
;
2499 if (subobj_byte_offset
+ len
> max
)
2500 invalid_synthetic_pointer ();
2502 /* Preserve VALUE because we are going to free values back
2503 to the mark, but we still need the value contents
2505 value_incref (value
);
2506 free_values
.free_to_mark ();
2507 cleanup
= make_cleanup_value_free (value
);
2509 retval
= allocate_value (subobj_type
);
2511 /* The given offset is relative to the actual object. */
2512 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2513 subobj_byte_offset
+= n
- max
;
2515 memcpy (value_contents_raw (retval
),
2516 value_contents_all (value
) + subobj_byte_offset
, len
);
2518 do_cleanups (cleanup
);
2522 case DWARF_VALUE_LITERAL
:
2525 size_t n
= TYPE_LENGTH (subobj_type
);
2527 if (subobj_byte_offset
+ n
> ctx
.len
)
2528 invalid_synthetic_pointer ();
2530 free_values
.free_to_mark ();
2531 retval
= allocate_value (subobj_type
);
2532 contents
= value_contents_raw (retval
);
2533 memcpy (contents
, ctx
.data
+ subobj_byte_offset
, n
);
2537 case DWARF_VALUE_OPTIMIZED_OUT
:
2538 free_values
.free_to_mark ();
2539 retval
= allocate_optimized_out_value (subobj_type
);
2542 /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
2543 operation by execute_stack_op. */
2544 case DWARF_VALUE_IMPLICIT_POINTER
:
2545 /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
2546 it can only be encountered when making a piece. */
2548 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2552 set_value_initialized (retval
, ctx
.initialized
);
2557 /* The exported interface to dwarf2_evaluate_loc_desc_full; it always
2558 passes 0 as the byte_offset. */
2561 dwarf2_evaluate_loc_desc (struct type
*type
, struct frame_info
*frame
,
2562 const gdb_byte
*data
, size_t size
,
2563 struct dwarf2_per_cu_data
*per_cu
)
2565 return dwarf2_evaluate_loc_desc_full (type
, frame
, data
, size
, per_cu
,
2569 /* Evaluates a dwarf expression and stores the result in VAL, expecting
2570 that the dwarf expression only produces a single CORE_ADDR. FRAME is the
2571 frame in which the expression is evaluated. ADDR is a context (location of
2572 a variable) and might be needed to evaluate the location expression.
2573 Returns 1 on success, 0 otherwise. */
2576 dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton
*dlbaton
,
2577 struct frame_info
*frame
,
2581 struct objfile
*objfile
;
2583 if (dlbaton
== NULL
|| dlbaton
->size
== 0)
2586 dwarf_evaluate_loc_desc ctx
;
2589 ctx
.per_cu
= dlbaton
->per_cu
;
2590 ctx
.obj_address
= addr
;
2592 objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
2594 ctx
.gdbarch
= get_objfile_arch (objfile
);
2595 ctx
.addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
2596 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (dlbaton
->per_cu
);
2597 ctx
.offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
2599 ctx
.eval (dlbaton
->data
, dlbaton
->size
);
2601 switch (ctx
.location
)
2603 case DWARF_VALUE_REGISTER
:
2604 case DWARF_VALUE_MEMORY
:
2605 case DWARF_VALUE_STACK
:
2606 *valp
= ctx
.fetch_address (0);
2607 if (ctx
.location
== DWARF_VALUE_REGISTER
)
2608 *valp
= ctx
.read_addr_from_reg (*valp
);
2610 case DWARF_VALUE_LITERAL
:
2611 *valp
= extract_signed_integer (ctx
.data
, ctx
.len
,
2612 gdbarch_byte_order (ctx
.gdbarch
));
2614 /* Unsupported dwarf values. */
2615 case DWARF_VALUE_OPTIMIZED_OUT
:
2616 case DWARF_VALUE_IMPLICIT_POINTER
:
2623 /* See dwarf2loc.h. */
2626 dwarf2_evaluate_property (const struct dynamic_prop
*prop
,
2627 struct frame_info
*frame
,
2628 struct property_addr_info
*addr_stack
,
2634 if (frame
== NULL
&& has_stack_frames ())
2635 frame
= get_selected_frame (NULL
);
2641 const struct dwarf2_property_baton
*baton
2642 = (const struct dwarf2_property_baton
*) prop
->data
.baton
;
2644 if (dwarf2_locexpr_baton_eval (&baton
->locexpr
, frame
,
2645 addr_stack
? addr_stack
->addr
: 0,
2648 if (baton
->referenced_type
)
2650 struct value
*val
= value_at (baton
->referenced_type
, *value
);
2652 *value
= value_as_address (val
);
2661 struct dwarf2_property_baton
*baton
2662 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2663 CORE_ADDR pc
= get_frame_address_in_block (frame
);
2664 const gdb_byte
*data
;
2668 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2671 val
= dwarf2_evaluate_loc_desc (baton
->referenced_type
, frame
, data
,
2672 size
, baton
->loclist
.per_cu
);
2673 if (!value_optimized_out (val
))
2675 *value
= value_as_address (val
);
2683 *value
= prop
->data
.const_val
;
2686 case PROP_ADDR_OFFSET
:
2688 struct dwarf2_property_baton
*baton
2689 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2690 struct property_addr_info
*pinfo
;
2693 for (pinfo
= addr_stack
; pinfo
!= NULL
; pinfo
= pinfo
->next
)
2694 if (pinfo
->type
== baton
->referenced_type
)
2697 error (_("cannot find reference address for offset property"));
2698 if (pinfo
->valaddr
!= NULL
)
2699 val
= value_from_contents
2700 (baton
->offset_info
.type
,
2701 pinfo
->valaddr
+ baton
->offset_info
.offset
);
2703 val
= value_at (baton
->offset_info
.type
,
2704 pinfo
->addr
+ baton
->offset_info
.offset
);
2705 *value
= value_as_address (val
);
2713 /* See dwarf2loc.h. */
2716 dwarf2_compile_property_to_c (string_file
&stream
,
2717 const char *result_name
,
2718 struct gdbarch
*gdbarch
,
2719 unsigned char *registers_used
,
2720 const struct dynamic_prop
*prop
,
2724 struct dwarf2_property_baton
*baton
2725 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2726 const gdb_byte
*data
;
2728 struct dwarf2_per_cu_data
*per_cu
;
2730 if (prop
->kind
== PROP_LOCEXPR
)
2732 data
= baton
->locexpr
.data
;
2733 size
= baton
->locexpr
.size
;
2734 per_cu
= baton
->locexpr
.per_cu
;
2738 gdb_assert (prop
->kind
== PROP_LOCLIST
);
2740 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2741 per_cu
= baton
->loclist
.per_cu
;
2744 compile_dwarf_bounds_to_c (stream
, result_name
, prop
, sym
, pc
,
2745 gdbarch
, registers_used
,
2746 dwarf2_per_cu_addr_size (per_cu
),
2747 data
, data
+ size
, per_cu
);
2751 /* Helper functions and baton for dwarf2_loc_desc_get_symbol_read_needs. */
2753 class symbol_needs_eval_context
: public dwarf_expr_context
2757 enum symbol_needs_kind needs
;
2758 struct dwarf2_per_cu_data
*per_cu
;
2760 /* Reads from registers do require a frame. */
2761 CORE_ADDR
read_addr_from_reg (int regnum
) OVERRIDE
2763 needs
= SYMBOL_NEEDS_FRAME
;
2767 /* "get_reg_value" callback: Reads from registers do require a
2770 struct value
*get_reg_value (struct type
*type
, int regnum
) OVERRIDE
2772 needs
= SYMBOL_NEEDS_FRAME
;
2773 return value_zero (type
, not_lval
);
2776 /* Reads from memory do not require a frame. */
2777 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
2779 memset (buf
, 0, len
);
2782 /* Frame-relative accesses do require a frame. */
2783 void get_frame_base (const gdb_byte
**start
, size_t *length
) OVERRIDE
2785 static gdb_byte lit0
= DW_OP_lit0
;
2790 needs
= SYMBOL_NEEDS_FRAME
;
2793 /* CFA accesses require a frame. */
2794 CORE_ADDR
get_frame_cfa () OVERRIDE
2796 needs
= SYMBOL_NEEDS_FRAME
;
2800 CORE_ADDR
get_frame_pc () OVERRIDE
2802 needs
= SYMBOL_NEEDS_FRAME
;
2806 /* Thread-local accesses require registers, but not a frame. */
2807 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
2809 if (needs
<= SYMBOL_NEEDS_REGISTERS
)
2810 needs
= SYMBOL_NEEDS_REGISTERS
;
2814 /* Helper interface of per_cu_dwarf_call for
2815 dwarf2_loc_desc_get_symbol_read_needs. */
2817 void dwarf_call (cu_offset die_offset
) OVERRIDE
2819 per_cu_dwarf_call (this, die_offset
, per_cu
);
2822 /* DW_OP_entry_value accesses require a caller, therefore a
2825 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
2826 union call_site_parameter_u kind_u
,
2827 int deref_size
) OVERRIDE
2829 needs
= SYMBOL_NEEDS_FRAME
;
2831 /* The expression may require some stub values on DWARF stack. */
2832 push_address (0, 0);
2835 /* DW_OP_GNU_addr_index doesn't require a frame. */
2837 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
2839 /* Nothing to do. */
2843 /* DW_OP_push_object_address has a frame already passed through. */
2845 CORE_ADDR
get_object_address () OVERRIDE
2847 /* Nothing to do. */
2852 /* Compute the correct symbol_needs_kind value for the location
2853 expression at DATA (length SIZE). */
2855 static enum symbol_needs_kind
2856 dwarf2_loc_desc_get_symbol_read_needs (const gdb_byte
*data
, size_t size
,
2857 struct dwarf2_per_cu_data
*per_cu
)
2860 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2862 scoped_value_mark free_values
;
2864 symbol_needs_eval_context ctx
;
2866 ctx
.needs
= SYMBOL_NEEDS_NONE
;
2867 ctx
.per_cu
= per_cu
;
2868 ctx
.gdbarch
= get_objfile_arch (objfile
);
2869 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2870 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2871 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2873 ctx
.eval (data
, size
);
2875 in_reg
= ctx
.location
== DWARF_VALUE_REGISTER
;
2877 if (ctx
.num_pieces
> 0)
2881 /* If the location has several pieces, and any of them are in
2882 registers, then we will need a frame to fetch them from. */
2883 for (i
= 0; i
< ctx
.num_pieces
; i
++)
2884 if (ctx
.pieces
[i
].location
== DWARF_VALUE_REGISTER
)
2889 ctx
.needs
= SYMBOL_NEEDS_FRAME
;
2893 /* A helper function that throws an unimplemented error mentioning a
2894 given DWARF operator. */
2897 unimplemented (unsigned int op
)
2899 const char *name
= get_DW_OP_name (op
);
2902 error (_("DWARF operator %s cannot be translated to an agent expression"),
2905 error (_("Unknown DWARF operator 0x%02x cannot be translated "
2906 "to an agent expression"),
2912 This is basically a wrapper on gdbarch_dwarf2_reg_to_regnum so that we
2913 can issue a complaint, which is better than having every target's
2914 implementation of dwarf2_reg_to_regnum do it. */
2917 dwarf_reg_to_regnum (struct gdbarch
*arch
, int dwarf_reg
)
2919 int reg
= gdbarch_dwarf2_reg_to_regnum (arch
, dwarf_reg
);
2923 complaint (&symfile_complaints
,
2924 _("bad DWARF register number %d"), dwarf_reg
);
2929 /* Subroutine of dwarf_reg_to_regnum_or_error to simplify it.
2930 Throw an error because DWARF_REG is bad. */
2933 throw_bad_regnum_error (ULONGEST dwarf_reg
)
2935 /* Still want to print -1 as "-1".
2936 We *could* have int and ULONGEST versions of dwarf2_reg_to_regnum_or_error
2937 but that's overkill for now. */
2938 if ((int) dwarf_reg
== dwarf_reg
)
2939 error (_("Unable to access DWARF register number %d"), (int) dwarf_reg
);
2940 error (_("Unable to access DWARF register number %s"),
2941 pulongest (dwarf_reg
));
2944 /* See dwarf2loc.h. */
2947 dwarf_reg_to_regnum_or_error (struct gdbarch
*arch
, ULONGEST dwarf_reg
)
2951 if (dwarf_reg
> INT_MAX
)
2952 throw_bad_regnum_error (dwarf_reg
);
2953 /* Yes, we will end up issuing a complaint and an error if DWARF_REG is
2954 bad, but that's ok. */
2955 reg
= dwarf_reg_to_regnum (arch
, (int) dwarf_reg
);
2957 throw_bad_regnum_error (dwarf_reg
);
2961 /* A helper function that emits an access to memory. ARCH is the
2962 target architecture. EXPR is the expression which we are building.
2963 NBITS is the number of bits we want to read. This emits the
2964 opcodes needed to read the memory and then extract the desired
2968 access_memory (struct gdbarch
*arch
, struct agent_expr
*expr
, ULONGEST nbits
)
2970 ULONGEST nbytes
= (nbits
+ 7) / 8;
2972 gdb_assert (nbytes
> 0 && nbytes
<= sizeof (LONGEST
));
2975 ax_trace_quick (expr
, nbytes
);
2978 ax_simple (expr
, aop_ref8
);
2979 else if (nbits
<= 16)
2980 ax_simple (expr
, aop_ref16
);
2981 else if (nbits
<= 32)
2982 ax_simple (expr
, aop_ref32
);
2984 ax_simple (expr
, aop_ref64
);
2986 /* If we read exactly the number of bytes we wanted, we're done. */
2987 if (8 * nbytes
== nbits
)
2990 if (gdbarch_bits_big_endian (arch
))
2992 /* On a bits-big-endian machine, we want the high-order
2994 ax_const_l (expr
, 8 * nbytes
- nbits
);
2995 ax_simple (expr
, aop_rsh_unsigned
);
2999 /* On a bits-little-endian box, we want the low-order NBITS. */
3000 ax_zero_ext (expr
, nbits
);
3004 /* A helper function to return the frame's PC. */
3007 get_ax_pc (void *baton
)
3009 struct agent_expr
*expr
= (struct agent_expr
*) baton
;
3014 /* Compile a DWARF location expression to an agent expression.
3016 EXPR is the agent expression we are building.
3017 LOC is the agent value we modify.
3018 ARCH is the architecture.
3019 ADDR_SIZE is the size of addresses, in bytes.
3020 OP_PTR is the start of the location expression.
3021 OP_END is one past the last byte of the location expression.
3023 This will throw an exception for various kinds of errors -- for
3024 example, if the expression cannot be compiled, or if the expression
3028 dwarf2_compile_expr_to_ax (struct agent_expr
*expr
, struct axs_value
*loc
,
3029 struct gdbarch
*arch
, unsigned int addr_size
,
3030 const gdb_byte
*op_ptr
, const gdb_byte
*op_end
,
3031 struct dwarf2_per_cu_data
*per_cu
)
3034 std::vector
<int> dw_labels
, patches
;
3035 const gdb_byte
* const base
= op_ptr
;
3036 const gdb_byte
*previous_piece
= op_ptr
;
3037 enum bfd_endian byte_order
= gdbarch_byte_order (arch
);
3038 ULONGEST bits_collected
= 0;
3039 unsigned int addr_size_bits
= 8 * addr_size
;
3040 int bits_big_endian
= gdbarch_bits_big_endian (arch
);
3042 std::vector
<int> offsets (op_end
- op_ptr
, -1);
3044 /* By default we are making an address. */
3045 loc
->kind
= axs_lvalue_memory
;
3047 while (op_ptr
< op_end
)
3049 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *op_ptr
;
3050 uint64_t uoffset
, reg
;
3054 offsets
[op_ptr
- base
] = expr
->len
;
3057 /* Our basic approach to code generation is to map DWARF
3058 operations directly to AX operations. However, there are
3061 First, DWARF works on address-sized units, but AX always uses
3062 LONGEST. For most operations we simply ignore this
3063 difference; instead we generate sign extensions as needed
3064 before division and comparison operations. It would be nice
3065 to omit the sign extensions, but there is no way to determine
3066 the size of the target's LONGEST. (This code uses the size
3067 of the host LONGEST in some cases -- that is a bug but it is
3070 Second, some DWARF operations cannot be translated to AX.
3071 For these we simply fail. See
3072 http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
3107 ax_const_l (expr
, op
- DW_OP_lit0
);
3111 uoffset
= extract_unsigned_integer (op_ptr
, addr_size
, byte_order
);
3112 op_ptr
+= addr_size
;
3113 /* Some versions of GCC emit DW_OP_addr before
3114 DW_OP_GNU_push_tls_address. In this case the value is an
3115 index, not an address. We don't support things like
3116 branching between the address and the TLS op. */
3117 if (op_ptr
>= op_end
|| *op_ptr
!= DW_OP_GNU_push_tls_address
)
3118 uoffset
+= dwarf2_per_cu_text_offset (per_cu
);
3119 ax_const_l (expr
, uoffset
);
3123 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 1, byte_order
));
3127 ax_const_l (expr
, extract_signed_integer (op_ptr
, 1, byte_order
));
3131 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 2, byte_order
));
3135 ax_const_l (expr
, extract_signed_integer (op_ptr
, 2, byte_order
));
3139 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 4, byte_order
));
3143 ax_const_l (expr
, extract_signed_integer (op_ptr
, 4, byte_order
));
3147 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 8, byte_order
));
3151 ax_const_l (expr
, extract_signed_integer (op_ptr
, 8, byte_order
));
3155 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3156 ax_const_l (expr
, uoffset
);
3159 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3160 ax_const_l (expr
, offset
);
3195 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3196 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_reg0
);
3197 loc
->kind
= axs_lvalue_register
;
3201 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3202 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3203 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3204 loc
->kind
= axs_lvalue_register
;
3207 case DW_OP_implicit_value
:
3211 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &len
);
3212 if (op_ptr
+ len
> op_end
)
3213 error (_("DW_OP_implicit_value: too few bytes available."));
3214 if (len
> sizeof (ULONGEST
))
3215 error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
3218 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, len
,
3221 dwarf_expr_require_composition (op_ptr
, op_end
,
3222 "DW_OP_implicit_value");
3224 loc
->kind
= axs_rvalue
;
3228 case DW_OP_stack_value
:
3229 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_stack_value");
3230 loc
->kind
= axs_rvalue
;
3265 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3266 i
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_breg0
);
3270 ax_const_l (expr
, offset
);
3271 ax_simple (expr
, aop_add
);
3276 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3277 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3278 i
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3282 ax_const_l (expr
, offset
);
3283 ax_simple (expr
, aop_add
);
3289 const gdb_byte
*datastart
;
3291 const struct block
*b
;
3292 struct symbol
*framefunc
;
3294 b
= block_for_pc (expr
->scope
);
3297 error (_("No block found for address"));
3299 framefunc
= block_linkage_function (b
);
3302 error (_("No function found for block"));
3304 func_get_frame_base_dwarf_block (framefunc
, expr
->scope
,
3305 &datastart
, &datalen
);
3307 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3308 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
, datastart
,
3309 datastart
+ datalen
, per_cu
);
3310 if (loc
->kind
== axs_lvalue_register
)
3311 require_rvalue (expr
, loc
);
3315 ax_const_l (expr
, offset
);
3316 ax_simple (expr
, aop_add
);
3319 loc
->kind
= axs_lvalue_memory
;
3324 ax_simple (expr
, aop_dup
);
3328 ax_simple (expr
, aop_pop
);
3333 ax_pick (expr
, offset
);
3337 ax_simple (expr
, aop_swap
);
3345 ax_simple (expr
, aop_rot
);
3349 case DW_OP_deref_size
:
3353 if (op
== DW_OP_deref_size
)
3358 if (size
!= 1 && size
!= 2 && size
!= 4 && size
!= 8)
3359 error (_("Unsupported size %d in %s"),
3360 size
, get_DW_OP_name (op
));
3361 access_memory (arch
, expr
, size
* TARGET_CHAR_BIT
);
3366 /* Sign extend the operand. */
3367 ax_ext (expr
, addr_size_bits
);
3368 ax_simple (expr
, aop_dup
);
3369 ax_const_l (expr
, 0);
3370 ax_simple (expr
, aop_less_signed
);
3371 ax_simple (expr
, aop_log_not
);
3372 i
= ax_goto (expr
, aop_if_goto
);
3373 /* We have to emit 0 - X. */
3374 ax_const_l (expr
, 0);
3375 ax_simple (expr
, aop_swap
);
3376 ax_simple (expr
, aop_sub
);
3377 ax_label (expr
, i
, expr
->len
);
3381 /* No need to sign extend here. */
3382 ax_const_l (expr
, 0);
3383 ax_simple (expr
, aop_swap
);
3384 ax_simple (expr
, aop_sub
);
3388 /* Sign extend the operand. */
3389 ax_ext (expr
, addr_size_bits
);
3390 ax_simple (expr
, aop_bit_not
);
3393 case DW_OP_plus_uconst
:
3394 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3395 /* It would be really weird to emit `DW_OP_plus_uconst 0',
3396 but we micro-optimize anyhow. */
3399 ax_const_l (expr
, reg
);
3400 ax_simple (expr
, aop_add
);
3405 ax_simple (expr
, aop_bit_and
);
3409 /* Sign extend the operands. */
3410 ax_ext (expr
, addr_size_bits
);
3411 ax_simple (expr
, aop_swap
);
3412 ax_ext (expr
, addr_size_bits
);
3413 ax_simple (expr
, aop_swap
);
3414 ax_simple (expr
, aop_div_signed
);
3418 ax_simple (expr
, aop_sub
);
3422 ax_simple (expr
, aop_rem_unsigned
);
3426 ax_simple (expr
, aop_mul
);
3430 ax_simple (expr
, aop_bit_or
);
3434 ax_simple (expr
, aop_add
);
3438 ax_simple (expr
, aop_lsh
);
3442 ax_simple (expr
, aop_rsh_unsigned
);
3446 ax_simple (expr
, aop_rsh_signed
);
3450 ax_simple (expr
, aop_bit_xor
);
3454 /* Sign extend the operands. */
3455 ax_ext (expr
, addr_size_bits
);
3456 ax_simple (expr
, aop_swap
);
3457 ax_ext (expr
, addr_size_bits
);
3458 /* Note no swap here: A <= B is !(B < A). */
3459 ax_simple (expr
, aop_less_signed
);
3460 ax_simple (expr
, aop_log_not
);
3464 /* Sign extend the operands. */
3465 ax_ext (expr
, addr_size_bits
);
3466 ax_simple (expr
, aop_swap
);
3467 ax_ext (expr
, addr_size_bits
);
3468 ax_simple (expr
, aop_swap
);
3469 /* A >= B is !(A < B). */
3470 ax_simple (expr
, aop_less_signed
);
3471 ax_simple (expr
, aop_log_not
);
3475 /* Sign extend the operands. */
3476 ax_ext (expr
, addr_size_bits
);
3477 ax_simple (expr
, aop_swap
);
3478 ax_ext (expr
, addr_size_bits
);
3479 /* No need for a second swap here. */
3480 ax_simple (expr
, aop_equal
);
3484 /* Sign extend the operands. */
3485 ax_ext (expr
, addr_size_bits
);
3486 ax_simple (expr
, aop_swap
);
3487 ax_ext (expr
, addr_size_bits
);
3488 ax_simple (expr
, aop_swap
);
3489 ax_simple (expr
, aop_less_signed
);
3493 /* Sign extend the operands. */
3494 ax_ext (expr
, addr_size_bits
);
3495 ax_simple (expr
, aop_swap
);
3496 ax_ext (expr
, addr_size_bits
);
3497 /* Note no swap here: A > B is B < A. */
3498 ax_simple (expr
, aop_less_signed
);
3502 /* Sign extend the operands. */
3503 ax_ext (expr
, addr_size_bits
);
3504 ax_simple (expr
, aop_swap
);
3505 ax_ext (expr
, addr_size_bits
);
3506 /* No need for a swap here. */
3507 ax_simple (expr
, aop_equal
);
3508 ax_simple (expr
, aop_log_not
);
3511 case DW_OP_call_frame_cfa
:
3514 CORE_ADDR text_offset
;
3516 const gdb_byte
*cfa_start
, *cfa_end
;
3518 if (dwarf2_fetch_cfa_info (arch
, expr
->scope
, per_cu
,
3520 &text_offset
, &cfa_start
, &cfa_end
))
3523 ax_reg (expr
, regnum
);
3526 ax_const_l (expr
, off
);
3527 ax_simple (expr
, aop_add
);
3532 /* Another expression. */
3533 ax_const_l (expr
, text_offset
);
3534 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3535 cfa_start
, cfa_end
, per_cu
);
3538 loc
->kind
= axs_lvalue_memory
;
3542 case DW_OP_GNU_push_tls_address
:
3543 case DW_OP_form_tls_address
:
3547 case DW_OP_push_object_address
:
3552 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3554 i
= ax_goto (expr
, aop_goto
);
3555 dw_labels
.push_back (op_ptr
+ offset
- base
);
3556 patches
.push_back (i
);
3560 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3562 /* Zero extend the operand. */
3563 ax_zero_ext (expr
, addr_size_bits
);
3564 i
= ax_goto (expr
, aop_if_goto
);
3565 dw_labels
.push_back (op_ptr
+ offset
- base
);
3566 patches
.push_back (i
);
3573 case DW_OP_bit_piece
:
3575 uint64_t size
, offset
;
3577 if (op_ptr
- 1 == previous_piece
)
3578 error (_("Cannot translate empty pieces to agent expressions"));
3579 previous_piece
= op_ptr
- 1;
3581 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &size
);
3582 if (op
== DW_OP_piece
)
3588 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &offset
);
3590 if (bits_collected
+ size
> 8 * sizeof (LONGEST
))
3591 error (_("Expression pieces exceed word size"));
3593 /* Access the bits. */
3596 case axs_lvalue_register
:
3597 ax_reg (expr
, loc
->u
.reg
);
3600 case axs_lvalue_memory
:
3601 /* Offset the pointer, if needed. */
3604 ax_const_l (expr
, offset
/ 8);
3605 ax_simple (expr
, aop_add
);
3608 access_memory (arch
, expr
, size
);
3612 /* For a bits-big-endian target, shift up what we already
3613 have. For a bits-little-endian target, shift up the
3614 new data. Note that there is a potential bug here if
3615 the DWARF expression leaves multiple values on the
3617 if (bits_collected
> 0)
3619 if (bits_big_endian
)
3621 ax_simple (expr
, aop_swap
);
3622 ax_const_l (expr
, size
);
3623 ax_simple (expr
, aop_lsh
);
3624 /* We don't need a second swap here, because
3625 aop_bit_or is symmetric. */
3629 ax_const_l (expr
, size
);
3630 ax_simple (expr
, aop_lsh
);
3632 ax_simple (expr
, aop_bit_or
);
3635 bits_collected
+= size
;
3636 loc
->kind
= axs_rvalue
;
3640 case DW_OP_GNU_uninit
:
3646 struct dwarf2_locexpr_baton block
;
3647 int size
= (op
== DW_OP_call2
? 2 : 4);
3649 uoffset
= extract_unsigned_integer (op_ptr
, size
, byte_order
);
3652 cu_offset offset
= (cu_offset
) uoffset
;
3653 block
= dwarf2_fetch_die_loc_cu_off (offset
, per_cu
,
3656 /* DW_OP_call_ref is currently not supported. */
3657 gdb_assert (block
.per_cu
== per_cu
);
3659 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3660 block
.data
, block
.data
+ block
.size
,
3665 case DW_OP_call_ref
:
3673 /* Patch all the branches we emitted. */
3674 for (i
= 0; i
< patches
.size (); ++i
)
3676 int targ
= offsets
[dw_labels
[i
]];
3678 internal_error (__FILE__
, __LINE__
, _("invalid label"));
3679 ax_label (expr
, patches
[i
], targ
);
3684 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
3685 evaluator to calculate the location. */
3686 static struct value
*
3687 locexpr_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
3689 struct dwarf2_locexpr_baton
*dlbaton
3690 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3693 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3694 dlbaton
->size
, dlbaton
->per_cu
);
3699 /* Return the value of SYMBOL in FRAME at (callee) FRAME's function
3700 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
3703 static struct value
*
3704 locexpr_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
3706 struct dwarf2_locexpr_baton
*dlbaton
3707 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3709 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3713 /* Implementation of get_symbol_read_needs from
3714 symbol_computed_ops. */
3716 static enum symbol_needs_kind
3717 locexpr_get_symbol_read_needs (struct symbol
*symbol
)
3719 struct dwarf2_locexpr_baton
*dlbaton
3720 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3722 return dwarf2_loc_desc_get_symbol_read_needs (dlbaton
->data
, dlbaton
->size
,
3726 /* Return true if DATA points to the end of a piece. END is one past
3727 the last byte in the expression. */
3730 piece_end_p (const gdb_byte
*data
, const gdb_byte
*end
)
3732 return data
== end
|| data
[0] == DW_OP_piece
|| data
[0] == DW_OP_bit_piece
;
3735 /* Helper for locexpr_describe_location_piece that finds the name of a
3739 locexpr_regname (struct gdbarch
*gdbarch
, int dwarf_regnum
)
3743 /* This doesn't use dwarf_reg_to_regnum_or_error on purpose.
3744 We'd rather print *something* here than throw an error. */
3745 regnum
= dwarf_reg_to_regnum (gdbarch
, dwarf_regnum
);
3746 /* gdbarch_register_name may just return "", return something more
3747 descriptive for bad register numbers. */
3750 /* The text is output as "$bad_register_number".
3751 That is why we use the underscores. */
3752 return _("bad_register_number");
3754 return gdbarch_register_name (gdbarch
, regnum
);
3757 /* Nicely describe a single piece of a location, returning an updated
3758 position in the bytecode sequence. This function cannot recognize
3759 all locations; if a location is not recognized, it simply returns
3760 DATA. If there is an error during reading, e.g. we run off the end
3761 of the buffer, an error is thrown. */
3763 static const gdb_byte
*
3764 locexpr_describe_location_piece (struct symbol
*symbol
, struct ui_file
*stream
,
3765 CORE_ADDR addr
, struct objfile
*objfile
,
3766 struct dwarf2_per_cu_data
*per_cu
,
3767 const gdb_byte
*data
, const gdb_byte
*end
,
3768 unsigned int addr_size
)
3770 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
3773 if (data
[0] >= DW_OP_reg0
&& data
[0] <= DW_OP_reg31
)
3775 fprintf_filtered (stream
, _("a variable in $%s"),
3776 locexpr_regname (gdbarch
, data
[0] - DW_OP_reg0
));
3779 else if (data
[0] == DW_OP_regx
)
3783 data
= safe_read_uleb128 (data
+ 1, end
, ®
);
3784 fprintf_filtered (stream
, _("a variable in $%s"),
3785 locexpr_regname (gdbarch
, reg
));
3787 else if (data
[0] == DW_OP_fbreg
)
3789 const struct block
*b
;
3790 struct symbol
*framefunc
;
3792 int64_t frame_offset
;
3793 const gdb_byte
*base_data
, *new_data
, *save_data
= data
;
3795 int64_t base_offset
= 0;
3797 new_data
= safe_read_sleb128 (data
+ 1, end
, &frame_offset
);
3798 if (!piece_end_p (new_data
, end
))
3802 b
= block_for_pc (addr
);
3805 error (_("No block found for address for symbol \"%s\"."),
3806 SYMBOL_PRINT_NAME (symbol
));
3808 framefunc
= block_linkage_function (b
);
3811 error (_("No function found for block for symbol \"%s\"."),
3812 SYMBOL_PRINT_NAME (symbol
));
3814 func_get_frame_base_dwarf_block (framefunc
, addr
, &base_data
, &base_size
);
3816 if (base_data
[0] >= DW_OP_breg0
&& base_data
[0] <= DW_OP_breg31
)
3818 const gdb_byte
*buf_end
;
3820 frame_reg
= base_data
[0] - DW_OP_breg0
;
3821 buf_end
= safe_read_sleb128 (base_data
+ 1, base_data
+ base_size
,
3823 if (buf_end
!= base_data
+ base_size
)
3824 error (_("Unexpected opcode after "
3825 "DW_OP_breg%u for symbol \"%s\"."),
3826 frame_reg
, SYMBOL_PRINT_NAME (symbol
));
3828 else if (base_data
[0] >= DW_OP_reg0
&& base_data
[0] <= DW_OP_reg31
)
3830 /* The frame base is just the register, with no offset. */
3831 frame_reg
= base_data
[0] - DW_OP_reg0
;
3836 /* We don't know what to do with the frame base expression,
3837 so we can't trace this variable; give up. */
3841 fprintf_filtered (stream
,
3842 _("a variable at frame base reg $%s offset %s+%s"),
3843 locexpr_regname (gdbarch
, frame_reg
),
3844 plongest (base_offset
), plongest (frame_offset
));
3846 else if (data
[0] >= DW_OP_breg0
&& data
[0] <= DW_OP_breg31
3847 && piece_end_p (data
, end
))
3851 data
= safe_read_sleb128 (data
+ 1, end
, &offset
);
3853 fprintf_filtered (stream
,
3854 _("a variable at offset %s from base reg $%s"),
3856 locexpr_regname (gdbarch
, data
[0] - DW_OP_breg0
));
3859 /* The location expression for a TLS variable looks like this (on a
3862 DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
3863 (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
3865 0x3 is the encoding for DW_OP_addr, which has an operand as long
3866 as the size of an address on the target machine (here is 8
3867 bytes). Note that more recent version of GCC emit DW_OP_const4u
3868 or DW_OP_const8u, depending on address size, rather than
3869 DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address.
3870 The operand represents the offset at which the variable is within
3871 the thread local storage. */
3873 else if (data
+ 1 + addr_size
< end
3874 && (data
[0] == DW_OP_addr
3875 || (addr_size
== 4 && data
[0] == DW_OP_const4u
)
3876 || (addr_size
== 8 && data
[0] == DW_OP_const8u
))
3877 && (data
[1 + addr_size
] == DW_OP_GNU_push_tls_address
3878 || data
[1 + addr_size
] == DW_OP_form_tls_address
)
3879 && piece_end_p (data
+ 2 + addr_size
, end
))
3882 offset
= extract_unsigned_integer (data
+ 1, addr_size
,
3883 gdbarch_byte_order (gdbarch
));
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
));
3890 data
+= 1 + addr_size
+ 1;
3893 /* With -gsplit-dwarf a TLS variable can also look like this:
3894 DW_AT_location : 3 byte block: fc 4 e0
3895 (DW_OP_GNU_const_index: 4;
3896 DW_OP_GNU_push_tls_address) */
3897 else if (data
+ 3 <= end
3898 && data
+ 1 + (leb128_size
= skip_leb128 (data
+ 1, end
)) < end
3899 && data
[0] == DW_OP_GNU_const_index
3901 && (data
[1 + leb128_size
] == DW_OP_GNU_push_tls_address
3902 || data
[1 + leb128_size
] == DW_OP_form_tls_address
)
3903 && piece_end_p (data
+ 2 + leb128_size
, end
))
3907 data
= safe_read_uleb128 (data
+ 1, end
, &offset
);
3908 offset
= dwarf2_read_addr_index (per_cu
, offset
);
3909 fprintf_filtered (stream
,
3910 _("a thread-local variable at offset 0x%s "
3911 "in the thread-local storage for `%s'"),
3912 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3916 else if (data
[0] >= DW_OP_lit0
3917 && data
[0] <= DW_OP_lit31
3919 && data
[1] == DW_OP_stack_value
)
3921 fprintf_filtered (stream
, _("the constant %d"), data
[0] - DW_OP_lit0
);
3928 /* Disassemble an expression, stopping at the end of a piece or at the
3929 end of the expression. Returns a pointer to the next unread byte
3930 in the input expression. If ALL is nonzero, then this function
3931 will keep going until it reaches the end of the expression.
3932 If there is an error during reading, e.g. we run off the end
3933 of the buffer, an error is thrown. */
3935 static const gdb_byte
*
3936 disassemble_dwarf_expression (struct ui_file
*stream
,
3937 struct gdbarch
*arch
, unsigned int addr_size
,
3938 int offset_size
, const gdb_byte
*start
,
3939 const gdb_byte
*data
, const gdb_byte
*end
,
3940 int indent
, int all
,
3941 struct dwarf2_per_cu_data
*per_cu
)
3945 || (data
[0] != DW_OP_piece
&& data
[0] != DW_OP_bit_piece
)))
3947 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *data
++;
3952 name
= get_DW_OP_name (op
);
3955 error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
3956 op
, (long) (data
- 1 - start
));
3957 fprintf_filtered (stream
, " %*ld: %s", indent
+ 4,
3958 (long) (data
- 1 - start
), name
);
3963 ul
= extract_unsigned_integer (data
, addr_size
,
3964 gdbarch_byte_order (arch
));
3966 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
3970 ul
= extract_unsigned_integer (data
, 1, gdbarch_byte_order (arch
));
3972 fprintf_filtered (stream
, " %s", pulongest (ul
));
3975 l
= extract_signed_integer (data
, 1, gdbarch_byte_order (arch
));
3977 fprintf_filtered (stream
, " %s", plongest (l
));
3980 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
3982 fprintf_filtered (stream
, " %s", pulongest (ul
));
3985 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
3987 fprintf_filtered (stream
, " %s", plongest (l
));
3990 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
3992 fprintf_filtered (stream
, " %s", pulongest (ul
));
3995 l
= extract_signed_integer (data
, 4, gdbarch_byte_order (arch
));
3997 fprintf_filtered (stream
, " %s", plongest (l
));
4000 ul
= extract_unsigned_integer (data
, 8, gdbarch_byte_order (arch
));
4002 fprintf_filtered (stream
, " %s", pulongest (ul
));
4005 l
= extract_signed_integer (data
, 8, gdbarch_byte_order (arch
));
4007 fprintf_filtered (stream
, " %s", plongest (l
));
4010 data
= safe_read_uleb128 (data
, end
, &ul
);
4011 fprintf_filtered (stream
, " %s", pulongest (ul
));
4014 data
= safe_read_sleb128 (data
, end
, &l
);
4015 fprintf_filtered (stream
, " %s", plongest (l
));
4050 fprintf_filtered (stream
, " [$%s]",
4051 locexpr_regname (arch
, op
- DW_OP_reg0
));
4055 data
= safe_read_uleb128 (data
, end
, &ul
);
4056 fprintf_filtered (stream
, " %s [$%s]", pulongest (ul
),
4057 locexpr_regname (arch
, (int) ul
));
4060 case DW_OP_implicit_value
:
4061 data
= safe_read_uleb128 (data
, end
, &ul
);
4063 fprintf_filtered (stream
, " %s", pulongest (ul
));
4098 data
= safe_read_sleb128 (data
, end
, &l
);
4099 fprintf_filtered (stream
, " %s [$%s]", plongest (l
),
4100 locexpr_regname (arch
, op
- DW_OP_breg0
));
4104 data
= safe_read_uleb128 (data
, end
, &ul
);
4105 data
= safe_read_sleb128 (data
, end
, &l
);
4106 fprintf_filtered (stream
, " register %s [$%s] offset %s",
4108 locexpr_regname (arch
, (int) ul
),
4113 data
= safe_read_sleb128 (data
, end
, &l
);
4114 fprintf_filtered (stream
, " %s", plongest (l
));
4117 case DW_OP_xderef_size
:
4118 case DW_OP_deref_size
:
4120 fprintf_filtered (stream
, " %d", *data
);
4124 case DW_OP_plus_uconst
:
4125 data
= safe_read_uleb128 (data
, end
, &ul
);
4126 fprintf_filtered (stream
, " %s", pulongest (ul
));
4130 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4132 fprintf_filtered (stream
, " to %ld",
4133 (long) (data
+ l
- start
));
4137 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4139 fprintf_filtered (stream
, " %ld",
4140 (long) (data
+ l
- start
));
4144 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4146 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 2));
4150 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4152 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4155 case DW_OP_call_ref
:
4156 ul
= extract_unsigned_integer (data
, offset_size
,
4157 gdbarch_byte_order (arch
));
4158 data
+= offset_size
;
4159 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4163 data
= safe_read_uleb128 (data
, end
, &ul
);
4164 fprintf_filtered (stream
, " %s (bytes)", pulongest (ul
));
4167 case DW_OP_bit_piece
:
4171 data
= safe_read_uleb128 (data
, end
, &ul
);
4172 data
= safe_read_uleb128 (data
, end
, &offset
);
4173 fprintf_filtered (stream
, " size %s offset %s (bits)",
4174 pulongest (ul
), pulongest (offset
));
4178 case DW_OP_implicit_pointer
:
4179 case DW_OP_GNU_implicit_pointer
:
4181 ul
= extract_unsigned_integer (data
, offset_size
,
4182 gdbarch_byte_order (arch
));
4183 data
+= offset_size
;
4185 data
= safe_read_sleb128 (data
, end
, &l
);
4187 fprintf_filtered (stream
, " DIE %s offset %s",
4188 phex_nz (ul
, offset_size
),
4193 case DW_OP_deref_type
:
4194 case DW_OP_GNU_deref_type
:
4196 int addr_size
= *data
++;
4199 data
= safe_read_uleb128 (data
, end
, &ul
);
4200 cu_offset offset
= (cu_offset
) ul
;
4201 type
= dwarf2_get_die_type (offset
, per_cu
);
4202 fprintf_filtered (stream
, "<");
4203 type_print (type
, "", stream
, -1);
4204 fprintf_filtered (stream
, " [0x%s]> %d",
4205 phex_nz (to_underlying (offset
), 0),
4210 case DW_OP_const_type
:
4211 case DW_OP_GNU_const_type
:
4215 data
= safe_read_uleb128 (data
, end
, &ul
);
4216 cu_offset type_die
= (cu_offset
) ul
;
4217 type
= dwarf2_get_die_type (type_die
, per_cu
);
4218 fprintf_filtered (stream
, "<");
4219 type_print (type
, "", stream
, -1);
4220 fprintf_filtered (stream
, " [0x%s]>",
4221 phex_nz (to_underlying (type_die
), 0));
4225 case DW_OP_regval_type
:
4226 case DW_OP_GNU_regval_type
:
4231 data
= safe_read_uleb128 (data
, end
, ®
);
4232 data
= safe_read_uleb128 (data
, end
, &ul
);
4233 cu_offset type_die
= (cu_offset
) ul
;
4235 type
= dwarf2_get_die_type (type_die
, per_cu
);
4236 fprintf_filtered (stream
, "<");
4237 type_print (type
, "", stream
, -1);
4238 fprintf_filtered (stream
, " [0x%s]> [$%s]",
4239 phex_nz (to_underlying (type_die
), 0),
4240 locexpr_regname (arch
, reg
));
4245 case DW_OP_GNU_convert
:
4246 case DW_OP_reinterpret
:
4247 case DW_OP_GNU_reinterpret
:
4249 data
= safe_read_uleb128 (data
, end
, &ul
);
4250 cu_offset type_die
= (cu_offset
) ul
;
4252 if (to_underlying (type_die
) == 0)
4253 fprintf_filtered (stream
, "<0>");
4258 type
= dwarf2_get_die_type (type_die
, per_cu
);
4259 fprintf_filtered (stream
, "<");
4260 type_print (type
, "", stream
, -1);
4261 fprintf_filtered (stream
, " [0x%s]>",
4262 phex_nz (to_underlying (type_die
), 0));
4267 case DW_OP_entry_value
:
4268 case DW_OP_GNU_entry_value
:
4269 data
= safe_read_uleb128 (data
, end
, &ul
);
4270 fputc_filtered ('\n', stream
);
4271 disassemble_dwarf_expression (stream
, arch
, addr_size
, offset_size
,
4272 start
, data
, data
+ ul
, indent
+ 2,
4277 case DW_OP_GNU_parameter_ref
:
4278 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4280 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4283 case DW_OP_GNU_addr_index
:
4284 data
= safe_read_uleb128 (data
, end
, &ul
);
4285 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4286 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
4288 case DW_OP_GNU_const_index
:
4289 data
= safe_read_uleb128 (data
, end
, &ul
);
4290 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4291 fprintf_filtered (stream
, " %s", pulongest (ul
));
4295 fprintf_filtered (stream
, "\n");
4301 /* Describe a single location, which may in turn consist of multiple
4305 locexpr_describe_location_1 (struct symbol
*symbol
, CORE_ADDR addr
,
4306 struct ui_file
*stream
,
4307 const gdb_byte
*data
, size_t size
,
4308 struct objfile
*objfile
, unsigned int addr_size
,
4309 int offset_size
, struct dwarf2_per_cu_data
*per_cu
)
4311 const gdb_byte
*end
= data
+ size
;
4312 int first_piece
= 1, bad
= 0;
4316 const gdb_byte
*here
= data
;
4317 int disassemble
= 1;
4322 fprintf_filtered (stream
, _(", and "));
4324 if (!dwarf_always_disassemble
)
4326 data
= locexpr_describe_location_piece (symbol
, stream
,
4327 addr
, objfile
, per_cu
,
4328 data
, end
, addr_size
);
4329 /* If we printed anything, or if we have an empty piece,
4330 then don't disassemble. */
4332 || data
[0] == DW_OP_piece
4333 || data
[0] == DW_OP_bit_piece
)
4338 fprintf_filtered (stream
, _("a complex DWARF expression:\n"));
4339 data
= disassemble_dwarf_expression (stream
,
4340 get_objfile_arch (objfile
),
4341 addr_size
, offset_size
, data
,
4343 dwarf_always_disassemble
,
4349 int empty
= data
== here
;
4352 fprintf_filtered (stream
, " ");
4353 if (data
[0] == DW_OP_piece
)
4357 data
= safe_read_uleb128 (data
+ 1, end
, &bytes
);
4360 fprintf_filtered (stream
, _("an empty %s-byte piece"),
4363 fprintf_filtered (stream
, _(" [%s-byte piece]"),
4366 else if (data
[0] == DW_OP_bit_piece
)
4368 uint64_t bits
, offset
;
4370 data
= safe_read_uleb128 (data
+ 1, end
, &bits
);
4371 data
= safe_read_uleb128 (data
, end
, &offset
);
4374 fprintf_filtered (stream
,
4375 _("an empty %s-bit piece"),
4378 fprintf_filtered (stream
,
4379 _(" [%s-bit piece, offset %s bits]"),
4380 pulongest (bits
), pulongest (offset
));
4390 if (bad
|| data
> end
)
4391 error (_("Corrupted DWARF2 expression for \"%s\"."),
4392 SYMBOL_PRINT_NAME (symbol
));
4395 /* Print a natural-language description of SYMBOL to STREAM. This
4396 version is for a symbol with a single location. */
4399 locexpr_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4400 struct ui_file
*stream
)
4402 struct dwarf2_locexpr_baton
*dlbaton
4403 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4404 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4405 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4406 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4408 locexpr_describe_location_1 (symbol
, addr
, stream
,
4409 dlbaton
->data
, dlbaton
->size
,
4410 objfile
, addr_size
, offset_size
,
4414 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4415 any necessary bytecode in AX. */
4418 locexpr_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4419 struct agent_expr
*ax
, struct axs_value
*value
)
4421 struct dwarf2_locexpr_baton
*dlbaton
4422 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4423 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4425 if (dlbaton
->size
== 0)
4426 value
->optimized_out
= 1;
4428 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
,
4429 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4433 /* symbol_computed_ops 'generate_c_location' method. */
4436 locexpr_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4437 struct gdbarch
*gdbarch
,
4438 unsigned char *registers_used
,
4439 CORE_ADDR pc
, const char *result_name
)
4441 struct dwarf2_locexpr_baton
*dlbaton
4442 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (sym
);
4443 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4445 if (dlbaton
->size
== 0)
4446 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4448 compile_dwarf_expr_to_c (stream
, result_name
,
4449 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4450 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4454 /* The set of location functions used with the DWARF-2 expression
4456 const struct symbol_computed_ops dwarf2_locexpr_funcs
= {
4457 locexpr_read_variable
,
4458 locexpr_read_variable_at_entry
,
4459 locexpr_get_symbol_read_needs
,
4460 locexpr_describe_location
,
4461 0, /* location_has_loclist */
4462 locexpr_tracepoint_var_ref
,
4463 locexpr_generate_c_location
4467 /* Wrapper functions for location lists. These generally find
4468 the appropriate location expression and call something above. */
4470 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
4471 evaluator to calculate the location. */
4472 static struct value
*
4473 loclist_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
4475 struct dwarf2_loclist_baton
*dlbaton
4476 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4478 const gdb_byte
*data
;
4480 CORE_ADDR pc
= frame
? get_frame_address_in_block (frame
) : 0;
4482 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4483 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, data
, size
,
4489 /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
4490 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
4493 Function always returns non-NULL value, it may be marked optimized out if
4494 inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
4495 if it cannot resolve the parameter for any reason. */
4497 static struct value
*
4498 loclist_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
4500 struct dwarf2_loclist_baton
*dlbaton
4501 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4502 const gdb_byte
*data
;
4506 if (frame
== NULL
|| !get_frame_func_if_available (frame
, &pc
))
4507 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4509 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4511 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4513 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, data
, size
);
4516 /* Implementation of get_symbol_read_needs from
4517 symbol_computed_ops. */
4519 static enum symbol_needs_kind
4520 loclist_symbol_needs (struct symbol
*symbol
)
4522 /* If there's a location list, then assume we need to have a frame
4523 to choose the appropriate location expression. With tracking of
4524 global variables this is not necessarily true, but such tracking
4525 is disabled in GCC at the moment until we figure out how to
4528 return SYMBOL_NEEDS_FRAME
;
4531 /* Print a natural-language description of SYMBOL to STREAM. This
4532 version applies when there is a list of different locations, each
4533 with a specified address range. */
4536 loclist_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4537 struct ui_file
*stream
)
4539 struct dwarf2_loclist_baton
*dlbaton
4540 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4541 const gdb_byte
*loc_ptr
, *buf_end
;
4542 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4543 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
4544 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
4545 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4546 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4547 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
4548 /* Adjust base_address for relocatable objects. */
4549 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
4550 CORE_ADDR base_address
= dlbaton
->base_address
+ base_offset
;
4553 loc_ptr
= dlbaton
->data
;
4554 buf_end
= dlbaton
->data
+ dlbaton
->size
;
4556 fprintf_filtered (stream
, _("multi-location:\n"));
4558 /* Iterate through locations until we run out. */
4561 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
4563 enum debug_loc_kind kind
;
4564 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
4566 if (dlbaton
->from_dwo
)
4567 kind
= decode_debug_loc_dwo_addresses (dlbaton
->per_cu
,
4568 loc_ptr
, buf_end
, &new_ptr
,
4569 &low
, &high
, byte_order
);
4571 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
4573 byte_order
, addr_size
,
4578 case DEBUG_LOC_END_OF_LIST
:
4581 case DEBUG_LOC_BASE_ADDRESS
:
4582 base_address
= high
+ base_offset
;
4583 fprintf_filtered (stream
, _(" Base address %s"),
4584 paddress (gdbarch
, base_address
));
4586 case DEBUG_LOC_START_END
:
4587 case DEBUG_LOC_START_LENGTH
:
4589 case DEBUG_LOC_BUFFER_OVERFLOW
:
4590 case DEBUG_LOC_INVALID_ENTRY
:
4591 error (_("Corrupted DWARF expression for symbol \"%s\"."),
4592 SYMBOL_PRINT_NAME (symbol
));
4594 gdb_assert_not_reached ("bad debug_loc_kind");
4597 /* Otherwise, a location expression entry. */
4598 low
+= base_address
;
4599 high
+= base_address
;
4601 low
= gdbarch_adjust_dwarf2_addr (gdbarch
, low
);
4602 high
= gdbarch_adjust_dwarf2_addr (gdbarch
, high
);
4604 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
4607 /* (It would improve readability to print only the minimum
4608 necessary digits of the second number of the range.) */
4609 fprintf_filtered (stream
, _(" Range %s-%s: "),
4610 paddress (gdbarch
, low
), paddress (gdbarch
, high
));
4612 /* Now describe this particular location. */
4613 locexpr_describe_location_1 (symbol
, low
, stream
, loc_ptr
, length
,
4614 objfile
, addr_size
, offset_size
,
4617 fprintf_filtered (stream
, "\n");
4623 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4624 any necessary bytecode in AX. */
4626 loclist_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4627 struct agent_expr
*ax
, struct axs_value
*value
)
4629 struct dwarf2_loclist_baton
*dlbaton
4630 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4631 const gdb_byte
*data
;
4633 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4635 data
= dwarf2_find_location_expression (dlbaton
, &size
, ax
->scope
);
4637 value
->optimized_out
= 1;
4639 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
, data
, data
+ size
,
4643 /* symbol_computed_ops 'generate_c_location' method. */
4646 loclist_generate_c_location (struct symbol
*sym
, string_file
&stream
,
4647 struct gdbarch
*gdbarch
,
4648 unsigned char *registers_used
,
4649 CORE_ADDR pc
, const char *result_name
)
4651 struct dwarf2_loclist_baton
*dlbaton
4652 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (sym
);
4653 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4654 const gdb_byte
*data
;
4657 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4659 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4661 compile_dwarf_expr_to_c (stream
, result_name
,
4662 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4667 /* The set of location functions used with the DWARF-2 expression
4668 evaluator and location lists. */
4669 const struct symbol_computed_ops dwarf2_loclist_funcs
= {
4670 loclist_read_variable
,
4671 loclist_read_variable_at_entry
,
4672 loclist_symbol_needs
,
4673 loclist_describe_location
,
4674 1, /* location_has_loclist */
4675 loclist_tracepoint_var_ref
,
4676 loclist_generate_c_location
4679 /* Provide a prototype to silence -Wmissing-prototypes. */
4680 extern initialize_file_ftype _initialize_dwarf2loc
;
4683 _initialize_dwarf2loc (void)
4685 add_setshow_zuinteger_cmd ("entry-values", class_maintenance
,
4686 &entry_values_debug
,
4687 _("Set entry values and tail call frames "
4689 _("Show entry values and tail call frames "
4691 _("When non-zero, the process of determining "
4692 "parameter values from function entry point "
4693 "and tail call frames will be printed."),
4695 show_entry_values_debug
,
4696 &setdebuglist
, &showdebuglist
);
4699 register_self_test (selftests::copy_bitwise_tests
);