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"
45 extern int dwarf_always_disassemble
;
47 static struct value
*dwarf2_evaluate_loc_desc_full (struct type
*type
,
48 struct frame_info
*frame
,
51 struct dwarf2_per_cu_data
*per_cu
,
54 static struct call_site_parameter
*dwarf_expr_reg_to_entry_parameter
55 (struct frame_info
*frame
,
56 enum call_site_parameter_kind kind
,
57 union call_site_parameter_u kind_u
,
58 struct dwarf2_per_cu_data
**per_cu_return
);
60 /* Until these have formal names, we define these here.
61 ref: http://gcc.gnu.org/wiki/DebugFission
62 Each entry in .debug_loc.dwo begins with a byte that describes the entry,
63 and is then followed by data specific to that entry. */
67 /* Indicates the end of the list of entries. */
68 DEBUG_LOC_END_OF_LIST
= 0,
70 /* This is followed by an unsigned LEB128 number that is an index into
71 .debug_addr and specifies the base address for all following entries. */
72 DEBUG_LOC_BASE_ADDRESS
= 1,
74 /* This is followed by two unsigned LEB128 numbers that are indices into
75 .debug_addr and specify the beginning and ending addresses, and then
76 a normal location expression as in .debug_loc. */
77 DEBUG_LOC_START_END
= 2,
79 /* This is followed by an unsigned LEB128 number that is an index into
80 .debug_addr and specifies the beginning address, and a 4 byte unsigned
81 number that specifies the length, and then a normal location expression
83 DEBUG_LOC_START_LENGTH
= 3,
85 /* An internal value indicating there is insufficient data. */
86 DEBUG_LOC_BUFFER_OVERFLOW
= -1,
88 /* An internal value indicating an invalid kind of entry was found. */
89 DEBUG_LOC_INVALID_ENTRY
= -2
92 /* Helper function which throws an error if a synthetic pointer is
96 invalid_synthetic_pointer (void)
98 error (_("access outside bounds of object "
99 "referenced via synthetic pointer"));
102 /* Decode the addresses in a non-dwo .debug_loc entry.
103 A pointer to the next byte to examine is returned in *NEW_PTR.
104 The encoded low,high addresses are return in *LOW,*HIGH.
105 The result indicates the kind of entry found. */
107 static enum debug_loc_kind
108 decode_debug_loc_addresses (const gdb_byte
*loc_ptr
, const gdb_byte
*buf_end
,
109 const gdb_byte
**new_ptr
,
110 CORE_ADDR
*low
, CORE_ADDR
*high
,
111 enum bfd_endian byte_order
,
112 unsigned int addr_size
,
115 CORE_ADDR base_mask
= ~(~(CORE_ADDR
)1 << (addr_size
* 8 - 1));
117 if (buf_end
- loc_ptr
< 2 * addr_size
)
118 return DEBUG_LOC_BUFFER_OVERFLOW
;
121 *low
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
123 *low
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
124 loc_ptr
+= addr_size
;
127 *high
= extract_signed_integer (loc_ptr
, addr_size
, byte_order
);
129 *high
= extract_unsigned_integer (loc_ptr
, addr_size
, byte_order
);
130 loc_ptr
+= addr_size
;
134 /* A base-address-selection entry. */
135 if ((*low
& base_mask
) == base_mask
)
136 return DEBUG_LOC_BASE_ADDRESS
;
138 /* An end-of-list entry. */
139 if (*low
== 0 && *high
== 0)
140 return DEBUG_LOC_END_OF_LIST
;
142 return DEBUG_LOC_START_END
;
145 /* Decode the addresses in .debug_loc.dwo entry.
146 A pointer to the next byte to examine is returned in *NEW_PTR.
147 The encoded low,high addresses are return in *LOW,*HIGH.
148 The result indicates the kind of entry found. */
150 static enum debug_loc_kind
151 decode_debug_loc_dwo_addresses (struct dwarf2_per_cu_data
*per_cu
,
152 const gdb_byte
*loc_ptr
,
153 const gdb_byte
*buf_end
,
154 const gdb_byte
**new_ptr
,
155 CORE_ADDR
*low
, CORE_ADDR
*high
,
156 enum bfd_endian byte_order
)
158 uint64_t low_index
, high_index
;
160 if (loc_ptr
== buf_end
)
161 return DEBUG_LOC_BUFFER_OVERFLOW
;
165 case DEBUG_LOC_END_OF_LIST
:
167 return DEBUG_LOC_END_OF_LIST
;
168 case DEBUG_LOC_BASE_ADDRESS
:
170 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
172 return DEBUG_LOC_BUFFER_OVERFLOW
;
173 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
175 return DEBUG_LOC_BASE_ADDRESS
;
176 case DEBUG_LOC_START_END
:
177 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
179 return DEBUG_LOC_BUFFER_OVERFLOW
;
180 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
181 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &high_index
);
183 return DEBUG_LOC_BUFFER_OVERFLOW
;
184 *high
= dwarf2_read_addr_index (per_cu
, high_index
);
186 return DEBUG_LOC_START_END
;
187 case DEBUG_LOC_START_LENGTH
:
188 loc_ptr
= gdb_read_uleb128 (loc_ptr
, buf_end
, &low_index
);
190 return DEBUG_LOC_BUFFER_OVERFLOW
;
191 *low
= dwarf2_read_addr_index (per_cu
, low_index
);
192 if (loc_ptr
+ 4 > buf_end
)
193 return DEBUG_LOC_BUFFER_OVERFLOW
;
195 *high
+= extract_unsigned_integer (loc_ptr
, 4, byte_order
);
196 *new_ptr
= loc_ptr
+ 4;
197 return DEBUG_LOC_START_LENGTH
;
199 return DEBUG_LOC_INVALID_ENTRY
;
203 /* A function for dealing with location lists. Given a
204 symbol baton (BATON) and a pc value (PC), find the appropriate
205 location expression, set *LOCEXPR_LENGTH, and return a pointer
206 to the beginning of the expression. Returns NULL on failure.
208 For now, only return the first matching location expression; there
209 can be more than one in the list. */
212 dwarf2_find_location_expression (struct dwarf2_loclist_baton
*baton
,
213 size_t *locexpr_length
, CORE_ADDR pc
)
215 struct objfile
*objfile
= dwarf2_per_cu_objfile (baton
->per_cu
);
216 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
217 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
218 unsigned int addr_size
= dwarf2_per_cu_addr_size (baton
->per_cu
);
219 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
220 /* Adjust base_address for relocatable objects. */
221 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (baton
->per_cu
);
222 CORE_ADDR base_address
= baton
->base_address
+ base_offset
;
223 const gdb_byte
*loc_ptr
, *buf_end
;
225 loc_ptr
= baton
->data
;
226 buf_end
= baton
->data
+ baton
->size
;
230 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
232 enum debug_loc_kind kind
;
233 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
236 kind
= decode_debug_loc_dwo_addresses (baton
->per_cu
,
237 loc_ptr
, buf_end
, &new_ptr
,
238 &low
, &high
, byte_order
);
240 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
242 byte_order
, addr_size
,
247 case DEBUG_LOC_END_OF_LIST
:
250 case DEBUG_LOC_BASE_ADDRESS
:
251 base_address
= high
+ base_offset
;
253 case DEBUG_LOC_START_END
:
254 case DEBUG_LOC_START_LENGTH
:
256 case DEBUG_LOC_BUFFER_OVERFLOW
:
257 case DEBUG_LOC_INVALID_ENTRY
:
258 error (_("dwarf2_find_location_expression: "
259 "Corrupted DWARF expression."));
261 gdb_assert_not_reached ("bad debug_loc_kind");
264 /* Otherwise, a location expression entry.
265 If the entry is from a DWO, don't add base address: the entry is from
266 .debug_addr which already has the DWARF "base address". We still add
267 base_offset in case we're debugging a PIE executable. */
276 high
+= base_address
;
279 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
282 if (low
== high
&& pc
== low
)
284 /* This is entry PC record present only at entry point
285 of a function. Verify it is really the function entry point. */
287 const struct block
*pc_block
= block_for_pc (pc
);
288 struct symbol
*pc_func
= NULL
;
291 pc_func
= block_linkage_function (pc_block
);
293 if (pc_func
&& pc
== BLOCK_START (SYMBOL_BLOCK_VALUE (pc_func
)))
295 *locexpr_length
= length
;
300 if (pc
>= low
&& pc
< high
)
302 *locexpr_length
= length
;
310 /* This is the baton used when performing dwarf2 expression
312 struct dwarf_expr_baton
314 struct frame_info
*frame
;
315 struct dwarf2_per_cu_data
*per_cu
;
316 CORE_ADDR obj_address
;
319 /* Implement find_frame_base_location method for LOC_BLOCK functions using
320 DWARF expression for its DW_AT_frame_base. */
323 locexpr_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
324 const gdb_byte
**start
, size_t *length
)
326 struct dwarf2_locexpr_baton
*symbaton
327 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
329 *length
= symbaton
->size
;
330 *start
= symbaton
->data
;
333 /* Implement the struct symbol_block_ops::get_frame_base method for
334 LOC_BLOCK functions using a DWARF expression as its DW_AT_frame_base. */
337 locexpr_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
339 struct gdbarch
*gdbarch
;
341 struct dwarf2_locexpr_baton
*dlbaton
;
342 const gdb_byte
*start
;
344 struct value
*result
;
346 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
347 Thus, it's supposed to provide the find_frame_base_location method as
349 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
351 gdbarch
= get_frame_arch (frame
);
352 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
353 dlbaton
= (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
355 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
356 (framefunc
, get_frame_pc (frame
), &start
, &length
);
357 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
360 /* The DW_AT_frame_base attribute contains a location description which
361 computes the base address itself. However, the call to
362 dwarf2_evaluate_loc_desc returns a value representing a variable at
363 that address. The frame base address is thus this variable's
365 return value_address (result
);
368 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
369 function uses DWARF expression for its DW_AT_frame_base. */
371 const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs
=
373 locexpr_find_frame_base_location
,
374 locexpr_get_frame_base
377 /* Implement find_frame_base_location method for LOC_BLOCK functions using
378 DWARF location list for its DW_AT_frame_base. */
381 loclist_find_frame_base_location (struct symbol
*framefunc
, CORE_ADDR pc
,
382 const gdb_byte
**start
, size_t *length
)
384 struct dwarf2_loclist_baton
*symbaton
385 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
387 *start
= dwarf2_find_location_expression (symbaton
, length
, pc
);
390 /* Implement the struct symbol_block_ops::get_frame_base method for
391 LOC_BLOCK functions using a DWARF location list as its DW_AT_frame_base. */
394 loclist_get_frame_base (struct symbol
*framefunc
, struct frame_info
*frame
)
396 struct gdbarch
*gdbarch
;
398 struct dwarf2_loclist_baton
*dlbaton
;
399 const gdb_byte
*start
;
401 struct value
*result
;
403 /* If this method is called, then FRAMEFUNC is supposed to be a DWARF block.
404 Thus, it's supposed to provide the find_frame_base_location method as
406 gdb_assert (SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
!= NULL
);
408 gdbarch
= get_frame_arch (frame
);
409 type
= builtin_type (gdbarch
)->builtin_data_ptr
;
410 dlbaton
= (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (framefunc
);
412 SYMBOL_BLOCK_OPS (framefunc
)->find_frame_base_location
413 (framefunc
, get_frame_pc (frame
), &start
, &length
);
414 result
= dwarf2_evaluate_loc_desc (type
, frame
, start
, length
,
417 /* The DW_AT_frame_base attribute contains a location description which
418 computes the base address itself. However, the call to
419 dwarf2_evaluate_loc_desc returns a value representing a variable at
420 that address. The frame base address is thus this variable's
422 return value_address (result
);
425 /* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
426 function uses DWARF location list for its DW_AT_frame_base. */
428 const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs
=
430 loclist_find_frame_base_location
,
431 loclist_get_frame_base
434 /* See dwarf2loc.h. */
437 func_get_frame_base_dwarf_block (struct symbol
*framefunc
, CORE_ADDR pc
,
438 const gdb_byte
**start
, size_t *length
)
440 if (SYMBOL_BLOCK_OPS (framefunc
) != NULL
)
442 const struct symbol_block_ops
*ops_block
= SYMBOL_BLOCK_OPS (framefunc
);
444 ops_block
->find_frame_base_location (framefunc
, pc
, start
, length
);
450 error (_("Could not find the frame base for \"%s\"."),
451 SYMBOL_NATURAL_NAME (framefunc
));
455 get_frame_pc_for_per_cu_dwarf_call (void *baton
)
457 dwarf_expr_context
*ctx
= (dwarf_expr_context
*) baton
;
459 return ctx
->get_frame_pc ();
463 per_cu_dwarf_call (struct dwarf_expr_context
*ctx
, cu_offset die_offset
,
464 struct dwarf2_per_cu_data
*per_cu
)
466 struct dwarf2_locexpr_baton block
;
468 block
= dwarf2_fetch_die_loc_cu_off (die_offset
, per_cu
,
469 get_frame_pc_for_per_cu_dwarf_call
,
472 /* DW_OP_call_ref is currently not supported. */
473 gdb_assert (block
.per_cu
== per_cu
);
475 ctx
->eval (block
.data
, block
.size
);
478 class dwarf_evaluate_loc_desc
: public dwarf_expr_context
482 struct frame_info
*frame
;
483 struct dwarf2_per_cu_data
*per_cu
;
484 CORE_ADDR obj_address
;
486 /* Helper function for dwarf2_evaluate_loc_desc. Computes the CFA for
487 the frame in BATON. */
489 CORE_ADDR
get_frame_cfa () OVERRIDE
491 return dwarf2_frame_cfa (frame
);
494 /* Helper function for dwarf2_evaluate_loc_desc. Computes the PC for
495 the frame in BATON. */
497 CORE_ADDR
get_frame_pc () OVERRIDE
499 return get_frame_address_in_block (frame
);
502 /* Using the objfile specified in BATON, find the address for the
503 current thread's thread-local storage with offset OFFSET. */
504 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
506 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
508 return target_translate_tls_address (objfile
, offset
);
511 /* Helper interface of per_cu_dwarf_call for
512 dwarf2_evaluate_loc_desc. */
514 void dwarf_call (cu_offset die_offset
) OVERRIDE
516 per_cu_dwarf_call (this, die_offset
, per_cu
);
519 struct type
*get_base_type (cu_offset die_offset
, int size
) OVERRIDE
521 struct type
*result
= dwarf2_get_die_type (die_offset
, per_cu
);
523 error (_("Could not find type for DW_OP_GNU_const_type"));
524 if (size
!= 0 && TYPE_LENGTH (result
) != size
)
525 error (_("DW_OP_GNU_const_type has different sizes for type and data"));
529 /* Callback function for dwarf2_evaluate_loc_desc.
530 Fetch the address indexed by DW_OP_GNU_addr_index. */
532 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
534 return dwarf2_read_addr_index (per_cu
, index
);
537 /* Callback function for get_object_address. Return the address of the VLA
540 CORE_ADDR
get_object_address () OVERRIDE
542 if (obj_address
== 0)
543 error (_("Location address is not set."));
547 /* Execute DWARF block of call_site_parameter which matches KIND and
548 KIND_U. Choose DEREF_SIZE value of that parameter. Search
549 caller of this objects's frame.
551 The caller can be from a different CU - per_cu_dwarf_call
552 implementation can be more simple as it does not support cross-CU
555 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
556 union call_site_parameter_u kind_u
,
557 int deref_size
) OVERRIDE
559 struct frame_info
*caller_frame
;
560 struct dwarf2_per_cu_data
*caller_per_cu
;
561 struct call_site_parameter
*parameter
;
562 const gdb_byte
*data_src
;
565 caller_frame
= get_prev_frame (frame
);
567 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
569 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
570 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
572 /* DEREF_SIZE size is not verified here. */
573 if (data_src
== NULL
)
574 throw_error (NO_ENTRY_VALUE_ERROR
,
575 _("Cannot resolve DW_AT_GNU_call_site_data_value"));
577 scoped_restore save_frame
= make_scoped_restore (&this->frame
,
579 scoped_restore save_per_cu
= make_scoped_restore (&this->per_cu
,
581 scoped_restore save_obj_addr
= make_scoped_restore (&this->obj_address
,
584 scoped_restore save_arch
= make_scoped_restore (&this->gdbarch
);
586 = get_objfile_arch (dwarf2_per_cu_objfile (per_cu
));
587 scoped_restore save_addr_size
= make_scoped_restore (&this->addr_size
);
588 this->addr_size
= dwarf2_per_cu_addr_size (per_cu
);
589 scoped_restore save_offset
= make_scoped_restore (&this->offset
);
590 this->offset
= dwarf2_per_cu_text_offset (per_cu
);
592 this->eval (data_src
, size
);
595 /* Using the frame specified in BATON, find the location expression
596 describing the frame base. Return a pointer to it in START and
597 its length in LENGTH. */
598 void get_frame_base (const gdb_byte
**start
, size_t * length
) OVERRIDE
600 /* FIXME: cagney/2003-03-26: This code should be using
601 get_frame_base_address(), and then implement a dwarf2 specific
603 struct symbol
*framefunc
;
604 const struct block
*bl
= get_frame_block (frame
, NULL
);
607 error (_("frame address is not available."));
609 /* Use block_linkage_function, which returns a real (not inlined)
610 function, instead of get_frame_function, which may return an
612 framefunc
= block_linkage_function (bl
);
614 /* If we found a frame-relative symbol then it was certainly within
615 some function associated with a frame. If we can't find the frame,
616 something has gone wrong. */
617 gdb_assert (framefunc
!= NULL
);
619 func_get_frame_base_dwarf_block (framefunc
,
620 get_frame_address_in_block (frame
),
624 /* Read memory at ADDR (length LEN) into BUF. */
626 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
628 read_memory (addr
, buf
, len
);
631 /* Using the frame specified in BATON, return the value of register
632 REGNUM, treated as a pointer. */
633 CORE_ADDR
read_addr_from_reg (int dwarf_regnum
) OVERRIDE
635 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
636 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
638 return address_from_register (regnum
, frame
);
641 /* Implement "get_reg_value" callback. */
643 struct value
*get_reg_value (struct type
*type
, int dwarf_regnum
) OVERRIDE
645 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
646 int regnum
= dwarf_reg_to_regnum_or_error (gdbarch
, dwarf_regnum
);
648 return value_from_register (type
, regnum
, frame
);
652 /* See dwarf2loc.h. */
654 unsigned int entry_values_debug
= 0;
656 /* Helper to set entry_values_debug. */
659 show_entry_values_debug (struct ui_file
*file
, int from_tty
,
660 struct cmd_list_element
*c
, const char *value
)
662 fprintf_filtered (file
,
663 _("Entry values and tail call frames debugging is %s.\n"),
667 /* Find DW_TAG_GNU_call_site's DW_AT_GNU_call_site_target address.
668 CALLER_FRAME (for registers) can be NULL if it is not known. This function
669 always returns valid address or it throws NO_ENTRY_VALUE_ERROR. */
672 call_site_to_target_addr (struct gdbarch
*call_site_gdbarch
,
673 struct call_site
*call_site
,
674 struct frame_info
*caller_frame
)
676 switch (FIELD_LOC_KIND (call_site
->target
))
678 case FIELD_LOC_KIND_DWARF_BLOCK
:
680 struct dwarf2_locexpr_baton
*dwarf_block
;
682 struct type
*caller_core_addr_type
;
683 struct gdbarch
*caller_arch
;
685 dwarf_block
= FIELD_DWARF_BLOCK (call_site
->target
);
686 if (dwarf_block
== NULL
)
688 struct bound_minimal_symbol msym
;
690 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
691 throw_error (NO_ENTRY_VALUE_ERROR
,
692 _("DW_AT_GNU_call_site_target is not specified "
694 paddress (call_site_gdbarch
, call_site
->pc
),
695 (msym
.minsym
== NULL
? "???"
696 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
699 if (caller_frame
== NULL
)
701 struct bound_minimal_symbol msym
;
703 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
704 throw_error (NO_ENTRY_VALUE_ERROR
,
705 _("DW_AT_GNU_call_site_target DWARF block resolving "
706 "requires known frame which is currently not "
707 "available at %s in %s"),
708 paddress (call_site_gdbarch
, call_site
->pc
),
709 (msym
.minsym
== NULL
? "???"
710 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
713 caller_arch
= get_frame_arch (caller_frame
);
714 caller_core_addr_type
= builtin_type (caller_arch
)->builtin_func_ptr
;
715 val
= dwarf2_evaluate_loc_desc (caller_core_addr_type
, caller_frame
,
716 dwarf_block
->data
, dwarf_block
->size
,
717 dwarf_block
->per_cu
);
718 /* DW_AT_GNU_call_site_target is a DWARF expression, not a DWARF
720 if (VALUE_LVAL (val
) == lval_memory
)
721 return value_address (val
);
723 return value_as_address (val
);
726 case FIELD_LOC_KIND_PHYSNAME
:
728 const char *physname
;
729 struct bound_minimal_symbol msym
;
731 physname
= FIELD_STATIC_PHYSNAME (call_site
->target
);
733 /* Handle both the mangled and demangled PHYSNAME. */
734 msym
= lookup_minimal_symbol (physname
, NULL
, NULL
);
735 if (msym
.minsym
== NULL
)
737 msym
= lookup_minimal_symbol_by_pc (call_site
->pc
- 1);
738 throw_error (NO_ENTRY_VALUE_ERROR
,
739 _("Cannot find function \"%s\" for a call site target "
741 physname
, paddress (call_site_gdbarch
, call_site
->pc
),
742 (msym
.minsym
== NULL
? "???"
743 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
746 return BMSYMBOL_VALUE_ADDRESS (msym
);
749 case FIELD_LOC_KIND_PHYSADDR
:
750 return FIELD_STATIC_PHYSADDR (call_site
->target
);
753 internal_error (__FILE__
, __LINE__
, _("invalid call site target kind"));
757 /* Convert function entry point exact address ADDR to the function which is
758 compliant with TAIL_CALL_LIST_COMPLETE condition. Throw
759 NO_ENTRY_VALUE_ERROR otherwise. */
761 static struct symbol
*
762 func_addr_to_tail_call_list (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
764 struct symbol
*sym
= find_pc_function (addr
);
767 if (sym
== NULL
|| BLOCK_START (SYMBOL_BLOCK_VALUE (sym
)) != addr
)
768 throw_error (NO_ENTRY_VALUE_ERROR
,
769 _("DW_TAG_GNU_call_site resolving failed to find function "
770 "name for address %s"),
771 paddress (gdbarch
, addr
));
773 type
= SYMBOL_TYPE (sym
);
774 gdb_assert (TYPE_CODE (type
) == TYPE_CODE_FUNC
);
775 gdb_assert (TYPE_SPECIFIC_FIELD (type
) == TYPE_SPECIFIC_FUNC
);
780 /* Verify function with entry point exact address ADDR can never call itself
781 via its tail calls (incl. transitively). Throw NO_ENTRY_VALUE_ERROR if it
782 can call itself via tail calls.
784 If a funtion can tail call itself its entry value based parameters are
785 unreliable. There is no verification whether the value of some/all
786 parameters is unchanged through the self tail call, we expect if there is
787 a self tail call all the parameters can be modified. */
790 func_verify_no_selftailcall (struct gdbarch
*gdbarch
, CORE_ADDR verify_addr
)
792 struct obstack addr_obstack
;
793 struct cleanup
*old_chain
;
796 /* Track here CORE_ADDRs which were already visited. */
799 /* The verification is completely unordered. Track here function addresses
800 which still need to be iterated. */
801 VEC (CORE_ADDR
) *todo
= NULL
;
803 obstack_init (&addr_obstack
);
804 old_chain
= make_cleanup_obstack_free (&addr_obstack
);
805 addr_hash
= htab_create_alloc_ex (64, core_addr_hash
, core_addr_eq
, NULL
,
806 &addr_obstack
, hashtab_obstack_allocate
,
808 make_cleanup_htab_delete (addr_hash
);
810 make_cleanup (VEC_cleanup (CORE_ADDR
), &todo
);
812 VEC_safe_push (CORE_ADDR
, todo
, verify_addr
);
813 while (!VEC_empty (CORE_ADDR
, todo
))
815 struct symbol
*func_sym
;
816 struct call_site
*call_site
;
818 addr
= VEC_pop (CORE_ADDR
, todo
);
820 func_sym
= func_addr_to_tail_call_list (gdbarch
, addr
);
822 for (call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (func_sym
));
823 call_site
; call_site
= call_site
->tail_call_next
)
825 CORE_ADDR target_addr
;
828 /* CALLER_FRAME with registers is not available for tail-call jumped
830 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
832 if (target_addr
== verify_addr
)
834 struct bound_minimal_symbol msym
;
836 msym
= lookup_minimal_symbol_by_pc (verify_addr
);
837 throw_error (NO_ENTRY_VALUE_ERROR
,
838 _("DW_OP_GNU_entry_value resolving has found "
839 "function \"%s\" at %s can call itself via tail "
841 (msym
.minsym
== NULL
? "???"
842 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
843 paddress (gdbarch
, verify_addr
));
846 slot
= htab_find_slot (addr_hash
, &target_addr
, INSERT
);
849 *slot
= obstack_copy (&addr_obstack
, &target_addr
,
850 sizeof (target_addr
));
851 VEC_safe_push (CORE_ADDR
, todo
, target_addr
);
856 do_cleanups (old_chain
);
859 /* Print user readable form of CALL_SITE->PC to gdb_stdlog. Used only for
860 ENTRY_VALUES_DEBUG. */
863 tailcall_dump (struct gdbarch
*gdbarch
, const struct call_site
*call_site
)
865 CORE_ADDR addr
= call_site
->pc
;
866 struct bound_minimal_symbol msym
= lookup_minimal_symbol_by_pc (addr
- 1);
868 fprintf_unfiltered (gdb_stdlog
, " %s(%s)", paddress (gdbarch
, addr
),
869 (msym
.minsym
== NULL
? "???"
870 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
874 /* vec.h needs single word type name, typedef it. */
875 typedef struct call_site
*call_sitep
;
877 /* Define VEC (call_sitep) functions. */
878 DEF_VEC_P (call_sitep
);
880 /* Intersect RESULTP with CHAIN to keep RESULTP unambiguous, keep in RESULTP
881 only top callers and bottom callees which are present in both. GDBARCH is
882 used only for ENTRY_VALUES_DEBUG. RESULTP is NULL after return if there are
883 no remaining possibilities to provide unambiguous non-trivial result.
884 RESULTP should point to NULL on the first (initialization) call. Caller is
885 responsible for xfree of any RESULTP data. */
888 chain_candidate (struct gdbarch
*gdbarch
, struct call_site_chain
**resultp
,
889 VEC (call_sitep
) *chain
)
891 struct call_site_chain
*result
= *resultp
;
892 long length
= VEC_length (call_sitep
, chain
);
893 int callers
, callees
, idx
;
897 /* Create the initial chain containing all the passed PCs. */
899 result
= ((struct call_site_chain
*)
900 xmalloc (sizeof (*result
)
901 + sizeof (*result
->call_site
) * (length
- 1)));
902 result
->length
= length
;
903 result
->callers
= result
->callees
= length
;
904 if (!VEC_empty (call_sitep
, chain
))
905 memcpy (result
->call_site
, VEC_address (call_sitep
, chain
),
906 sizeof (*result
->call_site
) * length
);
909 if (entry_values_debug
)
911 fprintf_unfiltered (gdb_stdlog
, "tailcall: initial:");
912 for (idx
= 0; idx
< length
; idx
++)
913 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
914 fputc_unfiltered ('\n', gdb_stdlog
);
920 if (entry_values_debug
)
922 fprintf_unfiltered (gdb_stdlog
, "tailcall: compare:");
923 for (idx
= 0; idx
< length
; idx
++)
924 tailcall_dump (gdbarch
, VEC_index (call_sitep
, chain
, idx
));
925 fputc_unfiltered ('\n', gdb_stdlog
);
928 /* Intersect callers. */
930 callers
= std::min ((long) result
->callers
, length
);
931 for (idx
= 0; idx
< callers
; idx
++)
932 if (result
->call_site
[idx
] != VEC_index (call_sitep
, chain
, idx
))
934 result
->callers
= idx
;
938 /* Intersect callees. */
940 callees
= std::min ((long) result
->callees
, length
);
941 for (idx
= 0; idx
< callees
; idx
++)
942 if (result
->call_site
[result
->length
- 1 - idx
]
943 != VEC_index (call_sitep
, chain
, length
- 1 - idx
))
945 result
->callees
= idx
;
949 if (entry_values_debug
)
951 fprintf_unfiltered (gdb_stdlog
, "tailcall: reduced:");
952 for (idx
= 0; idx
< result
->callers
; idx
++)
953 tailcall_dump (gdbarch
, result
->call_site
[idx
]);
954 fputs_unfiltered (" |", gdb_stdlog
);
955 for (idx
= 0; idx
< result
->callees
; idx
++)
956 tailcall_dump (gdbarch
, result
->call_site
[result
->length
957 - result
->callees
+ idx
]);
958 fputc_unfiltered ('\n', gdb_stdlog
);
961 if (result
->callers
== 0 && result
->callees
== 0)
963 /* There are no common callers or callees. It could be also a direct
964 call (which has length 0) with ambiguous possibility of an indirect
965 call - CALLERS == CALLEES == 0 is valid during the first allocation
966 but any subsequence processing of such entry means ambiguity. */
972 /* See call_site_find_chain_1 why there is no way to reach the bottom callee
973 PC again. In such case there must be two different code paths to reach
974 it. CALLERS + CALLEES equal to LENGTH in the case of self tail-call. */
975 gdb_assert (result
->callers
+ result
->callees
<= result
->length
);
978 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
979 assumed frames between them use GDBARCH. Use depth first search so we can
980 keep single CHAIN of call_site's back to CALLER_PC. Function recursion
981 would have needless GDB stack overhead. Caller is responsible for xfree of
982 the returned result. Any unreliability results in thrown
983 NO_ENTRY_VALUE_ERROR. */
985 static struct call_site_chain
*
986 call_site_find_chain_1 (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
989 CORE_ADDR save_callee_pc
= callee_pc
;
990 struct obstack addr_obstack
;
991 struct cleanup
*back_to_retval
, *back_to_workdata
;
992 struct call_site_chain
*retval
= NULL
;
993 struct call_site
*call_site
;
995 /* Mark CALL_SITEs so we do not visit the same ones twice. */
998 /* CHAIN contains only the intermediate CALL_SITEs. Neither CALLER_PC's
999 call_site nor any possible call_site at CALLEE_PC's function is there.
1000 Any CALL_SITE in CHAIN will be iterated to its siblings - via
1001 TAIL_CALL_NEXT. This is inappropriate for CALLER_PC's call_site. */
1002 VEC (call_sitep
) *chain
= NULL
;
1004 /* We are not interested in the specific PC inside the callee function. */
1005 callee_pc
= get_pc_function_start (callee_pc
);
1007 throw_error (NO_ENTRY_VALUE_ERROR
, _("Unable to find function for PC %s"),
1008 paddress (gdbarch
, save_callee_pc
));
1010 back_to_retval
= make_cleanup (free_current_contents
, &retval
);
1012 obstack_init (&addr_obstack
);
1013 back_to_workdata
= make_cleanup_obstack_free (&addr_obstack
);
1014 addr_hash
= htab_create_alloc_ex (64, core_addr_hash
, core_addr_eq
, NULL
,
1015 &addr_obstack
, hashtab_obstack_allocate
,
1017 make_cleanup_htab_delete (addr_hash
);
1019 make_cleanup (VEC_cleanup (call_sitep
), &chain
);
1021 /* Do not push CALL_SITE to CHAIN. Push there only the first tail call site
1022 at the target's function. All the possible tail call sites in the
1023 target's function will get iterated as already pushed into CHAIN via their
1025 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1029 CORE_ADDR target_func_addr
;
1030 struct call_site
*target_call_site
;
1032 /* CALLER_FRAME with registers is not available for tail-call jumped
1034 target_func_addr
= call_site_to_target_addr (gdbarch
, call_site
, NULL
);
1036 if (target_func_addr
== callee_pc
)
1038 chain_candidate (gdbarch
, &retval
, chain
);
1042 /* There is no way to reach CALLEE_PC again as we would prevent
1043 entering it twice as being already marked in ADDR_HASH. */
1044 target_call_site
= NULL
;
1048 struct symbol
*target_func
;
1050 target_func
= func_addr_to_tail_call_list (gdbarch
, target_func_addr
);
1051 target_call_site
= TYPE_TAIL_CALL_LIST (SYMBOL_TYPE (target_func
));
1056 /* Attempt to visit TARGET_CALL_SITE. */
1058 if (target_call_site
)
1062 slot
= htab_find_slot (addr_hash
, &target_call_site
->pc
, INSERT
);
1065 /* Successfully entered TARGET_CALL_SITE. */
1067 *slot
= &target_call_site
->pc
;
1068 VEC_safe_push (call_sitep
, chain
, target_call_site
);
1073 /* Backtrack (without revisiting the originating call_site). Try the
1074 callers's sibling; if there isn't any try the callers's callers's
1077 target_call_site
= NULL
;
1078 while (!VEC_empty (call_sitep
, chain
))
1080 call_site
= VEC_pop (call_sitep
, chain
);
1082 gdb_assert (htab_find_slot (addr_hash
, &call_site
->pc
,
1083 NO_INSERT
) != NULL
);
1084 htab_remove_elt (addr_hash
, &call_site
->pc
);
1086 target_call_site
= call_site
->tail_call_next
;
1087 if (target_call_site
)
1091 while (target_call_site
);
1093 if (VEC_empty (call_sitep
, chain
))
1096 call_site
= VEC_last (call_sitep
, chain
);
1101 struct bound_minimal_symbol msym_caller
, msym_callee
;
1103 msym_caller
= lookup_minimal_symbol_by_pc (caller_pc
);
1104 msym_callee
= lookup_minimal_symbol_by_pc (callee_pc
);
1105 throw_error (NO_ENTRY_VALUE_ERROR
,
1106 _("There are no unambiguously determinable intermediate "
1107 "callers or callees between caller function \"%s\" at %s "
1108 "and callee function \"%s\" at %s"),
1109 (msym_caller
.minsym
== NULL
1110 ? "???" : MSYMBOL_PRINT_NAME (msym_caller
.minsym
)),
1111 paddress (gdbarch
, caller_pc
),
1112 (msym_callee
.minsym
== NULL
1113 ? "???" : MSYMBOL_PRINT_NAME (msym_callee
.minsym
)),
1114 paddress (gdbarch
, callee_pc
));
1117 do_cleanups (back_to_workdata
);
1118 discard_cleanups (back_to_retval
);
1122 /* Create and return call_site_chain for CALLER_PC and CALLEE_PC. All the
1123 assumed frames between them use GDBARCH. If valid call_site_chain cannot be
1124 constructed return NULL. Caller is responsible for xfree of the returned
1127 struct call_site_chain
*
1128 call_site_find_chain (struct gdbarch
*gdbarch
, CORE_ADDR caller_pc
,
1129 CORE_ADDR callee_pc
)
1131 struct call_site_chain
*retval
= NULL
;
1135 retval
= call_site_find_chain_1 (gdbarch
, caller_pc
, callee_pc
);
1137 CATCH (e
, RETURN_MASK_ERROR
)
1139 if (e
.error
== NO_ENTRY_VALUE_ERROR
)
1141 if (entry_values_debug
)
1142 exception_print (gdb_stdout
, e
);
1147 throw_exception (e
);
1154 /* Return 1 if KIND and KIND_U match PARAMETER. Return 0 otherwise. */
1157 call_site_parameter_matches (struct call_site_parameter
*parameter
,
1158 enum call_site_parameter_kind kind
,
1159 union call_site_parameter_u kind_u
)
1161 if (kind
== parameter
->kind
)
1164 case CALL_SITE_PARAMETER_DWARF_REG
:
1165 return kind_u
.dwarf_reg
== parameter
->u
.dwarf_reg
;
1166 case CALL_SITE_PARAMETER_FB_OFFSET
:
1167 return kind_u
.fb_offset
== parameter
->u
.fb_offset
;
1168 case CALL_SITE_PARAMETER_PARAM_OFFSET
:
1169 return kind_u
.param_offset
.cu_off
== parameter
->u
.param_offset
.cu_off
;
1174 /* Fetch call_site_parameter from caller matching KIND and KIND_U.
1175 FRAME is for callee.
1177 Function always returns non-NULL, it throws NO_ENTRY_VALUE_ERROR
1180 static struct call_site_parameter
*
1181 dwarf_expr_reg_to_entry_parameter (struct frame_info
*frame
,
1182 enum call_site_parameter_kind kind
,
1183 union call_site_parameter_u kind_u
,
1184 struct dwarf2_per_cu_data
**per_cu_return
)
1186 CORE_ADDR func_addr
, caller_pc
;
1187 struct gdbarch
*gdbarch
;
1188 struct frame_info
*caller_frame
;
1189 struct call_site
*call_site
;
1191 /* Initialize it just to avoid a GCC false warning. */
1192 struct call_site_parameter
*parameter
= NULL
;
1193 CORE_ADDR target_addr
;
1195 while (get_frame_type (frame
) == INLINE_FRAME
)
1197 frame
= get_prev_frame (frame
);
1198 gdb_assert (frame
!= NULL
);
1201 func_addr
= get_frame_func (frame
);
1202 gdbarch
= get_frame_arch (frame
);
1203 caller_frame
= get_prev_frame (frame
);
1204 if (gdbarch
!= frame_unwind_arch (frame
))
1206 struct bound_minimal_symbol msym
1207 = lookup_minimal_symbol_by_pc (func_addr
);
1208 struct gdbarch
*caller_gdbarch
= frame_unwind_arch (frame
);
1210 throw_error (NO_ENTRY_VALUE_ERROR
,
1211 _("DW_OP_GNU_entry_value resolving callee gdbarch %s "
1212 "(of %s (%s)) does not match caller gdbarch %s"),
1213 gdbarch_bfd_arch_info (gdbarch
)->printable_name
,
1214 paddress (gdbarch
, func_addr
),
1215 (msym
.minsym
== NULL
? "???"
1216 : MSYMBOL_PRINT_NAME (msym
.minsym
)),
1217 gdbarch_bfd_arch_info (caller_gdbarch
)->printable_name
);
1220 if (caller_frame
== NULL
)
1222 struct bound_minimal_symbol msym
1223 = lookup_minimal_symbol_by_pc (func_addr
);
1225 throw_error (NO_ENTRY_VALUE_ERROR
, _("DW_OP_GNU_entry_value resolving "
1226 "requires caller of %s (%s)"),
1227 paddress (gdbarch
, func_addr
),
1228 (msym
.minsym
== NULL
? "???"
1229 : MSYMBOL_PRINT_NAME (msym
.minsym
)));
1231 caller_pc
= get_frame_pc (caller_frame
);
1232 call_site
= call_site_for_pc (gdbarch
, caller_pc
);
1234 target_addr
= call_site_to_target_addr (gdbarch
, call_site
, caller_frame
);
1235 if (target_addr
!= func_addr
)
1237 struct minimal_symbol
*target_msym
, *func_msym
;
1239 target_msym
= lookup_minimal_symbol_by_pc (target_addr
).minsym
;
1240 func_msym
= lookup_minimal_symbol_by_pc (func_addr
).minsym
;
1241 throw_error (NO_ENTRY_VALUE_ERROR
,
1242 _("DW_OP_GNU_entry_value resolving expects callee %s at %s "
1243 "but the called frame is for %s at %s"),
1244 (target_msym
== NULL
? "???"
1245 : MSYMBOL_PRINT_NAME (target_msym
)),
1246 paddress (gdbarch
, target_addr
),
1247 func_msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (func_msym
),
1248 paddress (gdbarch
, func_addr
));
1251 /* No entry value based parameters would be reliable if this function can
1252 call itself via tail calls. */
1253 func_verify_no_selftailcall (gdbarch
, func_addr
);
1255 for (iparams
= 0; iparams
< call_site
->parameter_count
; iparams
++)
1257 parameter
= &call_site
->parameter
[iparams
];
1258 if (call_site_parameter_matches (parameter
, kind
, kind_u
))
1261 if (iparams
== call_site
->parameter_count
)
1263 struct minimal_symbol
*msym
1264 = lookup_minimal_symbol_by_pc (caller_pc
).minsym
;
1266 /* DW_TAG_GNU_call_site_parameter will be missing just if GCC could not
1267 determine its value. */
1268 throw_error (NO_ENTRY_VALUE_ERROR
, _("Cannot find matching parameter "
1269 "at DW_TAG_GNU_call_site %s at %s"),
1270 paddress (gdbarch
, caller_pc
),
1271 msym
== NULL
? "???" : MSYMBOL_PRINT_NAME (msym
));
1274 *per_cu_return
= call_site
->per_cu
;
1278 /* Return value for PARAMETER matching DEREF_SIZE. If DEREF_SIZE is -1, return
1279 the normal DW_AT_GNU_call_site_value block. Otherwise return the
1280 DW_AT_GNU_call_site_data_value (dereferenced) block.
1282 TYPE and CALLER_FRAME specify how to evaluate the DWARF block into returned
1285 Function always returns non-NULL, non-optimized out value. It throws
1286 NO_ENTRY_VALUE_ERROR if it cannot resolve the value for any reason. */
1288 static struct value
*
1289 dwarf_entry_parameter_to_value (struct call_site_parameter
*parameter
,
1290 CORE_ADDR deref_size
, struct type
*type
,
1291 struct frame_info
*caller_frame
,
1292 struct dwarf2_per_cu_data
*per_cu
)
1294 const gdb_byte
*data_src
;
1298 data_src
= deref_size
== -1 ? parameter
->value
: parameter
->data_value
;
1299 size
= deref_size
== -1 ? parameter
->value_size
: parameter
->data_value_size
;
1301 /* DEREF_SIZE size is not verified here. */
1302 if (data_src
== NULL
)
1303 throw_error (NO_ENTRY_VALUE_ERROR
,
1304 _("Cannot resolve DW_AT_GNU_call_site_data_value"));
1306 /* DW_AT_GNU_call_site_value is a DWARF expression, not a DWARF
1307 location. Postprocessing of DWARF_VALUE_MEMORY would lose the type from
1309 data
= (gdb_byte
*) alloca (size
+ 1);
1310 memcpy (data
, data_src
, size
);
1311 data
[size
] = DW_OP_stack_value
;
1313 return dwarf2_evaluate_loc_desc (type
, caller_frame
, data
, size
+ 1, per_cu
);
1316 /* VALUE must be of type lval_computed with entry_data_value_funcs. Perform
1317 the indirect method on it, that is use its stored target value, the sole
1318 purpose of entry_data_value_funcs.. */
1320 static struct value
*
1321 entry_data_value_coerce_ref (const struct value
*value
)
1323 struct type
*checked_type
= check_typedef (value_type (value
));
1324 struct value
*target_val
;
1326 if (TYPE_CODE (checked_type
) != TYPE_CODE_REF
)
1329 target_val
= (struct value
*) value_computed_closure (value
);
1330 value_incref (target_val
);
1334 /* Implement copy_closure. */
1337 entry_data_value_copy_closure (const struct value
*v
)
1339 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1341 value_incref (target_val
);
1345 /* Implement free_closure. */
1348 entry_data_value_free_closure (struct value
*v
)
1350 struct value
*target_val
= (struct value
*) value_computed_closure (v
);
1352 value_free (target_val
);
1355 /* Vector for methods for an entry value reference where the referenced value
1356 is stored in the caller. On the first dereference use
1357 DW_AT_GNU_call_site_data_value in the caller. */
1359 static const struct lval_funcs entry_data_value_funcs
=
1363 NULL
, /* indirect */
1364 entry_data_value_coerce_ref
,
1365 NULL
, /* check_synthetic_pointer */
1366 entry_data_value_copy_closure
,
1367 entry_data_value_free_closure
1370 /* Read parameter of TYPE at (callee) FRAME's function entry. KIND and KIND_U
1371 are used to match DW_AT_location at the caller's
1372 DW_TAG_GNU_call_site_parameter.
1374 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1375 cannot resolve the parameter for any reason. */
1377 static struct value
*
1378 value_of_dwarf_reg_entry (struct type
*type
, struct frame_info
*frame
,
1379 enum call_site_parameter_kind kind
,
1380 union call_site_parameter_u kind_u
)
1382 struct type
*checked_type
= check_typedef (type
);
1383 struct type
*target_type
= TYPE_TARGET_TYPE (checked_type
);
1384 struct frame_info
*caller_frame
= get_prev_frame (frame
);
1385 struct value
*outer_val
, *target_val
, *val
;
1386 struct call_site_parameter
*parameter
;
1387 struct dwarf2_per_cu_data
*caller_per_cu
;
1389 parameter
= dwarf_expr_reg_to_entry_parameter (frame
, kind
, kind_u
,
1392 outer_val
= dwarf_entry_parameter_to_value (parameter
, -1 /* deref_size */,
1396 /* Check if DW_AT_GNU_call_site_data_value cannot be used. If it should be
1397 used and it is not available do not fall back to OUTER_VAL - dereferencing
1398 TYPE_CODE_REF with non-entry data value would give current value - not the
1401 if (TYPE_CODE (checked_type
) != TYPE_CODE_REF
1402 || TYPE_TARGET_TYPE (checked_type
) == NULL
)
1405 target_val
= dwarf_entry_parameter_to_value (parameter
,
1406 TYPE_LENGTH (target_type
),
1407 target_type
, caller_frame
,
1410 release_value (target_val
);
1411 val
= allocate_computed_value (type
, &entry_data_value_funcs
,
1412 target_val
/* closure */);
1414 /* Copy the referencing pointer to the new computed value. */
1415 memcpy (value_contents_raw (val
), value_contents_raw (outer_val
),
1416 TYPE_LENGTH (checked_type
));
1417 set_value_lazy (val
, 0);
1422 /* Read parameter of TYPE at (callee) FRAME's function entry. DATA and
1423 SIZE are DWARF block used to match DW_AT_location at the caller's
1424 DW_TAG_GNU_call_site_parameter.
1426 Function always returns non-NULL value. It throws NO_ENTRY_VALUE_ERROR if it
1427 cannot resolve the parameter for any reason. */
1429 static struct value
*
1430 value_of_dwarf_block_entry (struct type
*type
, struct frame_info
*frame
,
1431 const gdb_byte
*block
, size_t block_len
)
1433 union call_site_parameter_u kind_u
;
1435 kind_u
.dwarf_reg
= dwarf_block_to_dwarf_reg (block
, block
+ block_len
);
1436 if (kind_u
.dwarf_reg
!= -1)
1437 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_DWARF_REG
,
1440 if (dwarf_block_to_fb_offset (block
, block
+ block_len
, &kind_u
.fb_offset
))
1441 return value_of_dwarf_reg_entry (type
, frame
, CALL_SITE_PARAMETER_FB_OFFSET
,
1444 /* This can normally happen - throw NO_ENTRY_VALUE_ERROR to get the message
1445 suppressed during normal operation. The expression can be arbitrary if
1446 there is no caller-callee entry value binding expected. */
1447 throw_error (NO_ENTRY_VALUE_ERROR
,
1448 _("DWARF-2 expression error: DW_OP_GNU_entry_value is supported "
1449 "only for single DW_OP_reg* or for DW_OP_fbreg(*)"));
1452 struct piece_closure
1454 /* Reference count. */
1457 /* The CU from which this closure's expression came. */
1458 struct dwarf2_per_cu_data
*per_cu
;
1460 /* The number of pieces used to describe this variable. */
1463 /* The target address size, used only for DWARF_VALUE_STACK. */
1466 /* The pieces themselves. */
1467 struct dwarf_expr_piece
*pieces
;
1469 /* Frame ID of frame to which a register value is relative, used
1470 only by DWARF_VALUE_REGISTER. */
1471 struct frame_id frame_id
;
1474 /* Allocate a closure for a value formed from separately-described
1477 static struct piece_closure
*
1478 allocate_piece_closure (struct dwarf2_per_cu_data
*per_cu
,
1479 int n_pieces
, struct dwarf_expr_piece
*pieces
,
1480 int addr_size
, struct frame_info
*frame
)
1482 struct piece_closure
*c
= XCNEW (struct piece_closure
);
1487 c
->n_pieces
= n_pieces
;
1488 c
->addr_size
= addr_size
;
1489 c
->pieces
= XCNEWVEC (struct dwarf_expr_piece
, n_pieces
);
1491 c
->frame_id
= null_frame_id
;
1493 c
->frame_id
= get_frame_id (frame
);
1495 memcpy (c
->pieces
, pieces
, n_pieces
* sizeof (struct dwarf_expr_piece
));
1496 for (i
= 0; i
< n_pieces
; ++i
)
1497 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
1498 value_incref (c
->pieces
[i
].v
.value
);
1503 /* Copy NBITS bits from SOURCE to DEST starting at the given bit
1504 offsets. Use the bit order as specified by BITS_BIG_ENDIAN.
1505 Source and destination buffers must not overlap. */
1508 copy_bitwise (gdb_byte
*dest
, ULONGEST dest_offset
,
1509 const gdb_byte
*source
, ULONGEST source_offset
,
1510 ULONGEST nbits
, int bits_big_endian
)
1512 unsigned int buf
, avail
;
1517 if (bits_big_endian
)
1519 /* Start from the end, then work backwards. */
1520 dest_offset
+= nbits
- 1;
1521 dest
+= dest_offset
/ 8;
1522 dest_offset
= 7 - dest_offset
% 8;
1523 source_offset
+= nbits
- 1;
1524 source
+= source_offset
/ 8;
1525 source_offset
= 7 - source_offset
% 8;
1529 dest
+= dest_offset
/ 8;
1531 source
+= source_offset
/ 8;
1535 /* Fill BUF with DEST_OFFSET bits from the destination and 8 -
1536 SOURCE_OFFSET bits from the source. */
1537 buf
= *(bits_big_endian
? source
-- : source
++) >> source_offset
;
1538 buf
<<= dest_offset
;
1539 buf
|= *dest
& ((1 << dest_offset
) - 1);
1541 /* NBITS: bits yet to be written; AVAIL: BUF's fill level. */
1542 nbits
+= dest_offset
;
1543 avail
= dest_offset
+ 8 - source_offset
;
1545 /* Flush 8 bits from BUF, if appropriate. */
1546 if (nbits
>= 8 && avail
>= 8)
1548 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1554 /* Copy the middle part. */
1557 size_t len
= nbits
/ 8;
1559 /* Use a faster method for byte-aligned copies. */
1562 if (bits_big_endian
)
1566 memcpy (dest
+ 1, source
+ 1, len
);
1570 memcpy (dest
, source
, len
);
1579 buf
|= *(bits_big_endian
? source
-- : source
++) << avail
;
1580 *(bits_big_endian
? dest
-- : dest
++) = buf
;
1587 /* Write the last byte. */
1591 buf
|= *source
<< avail
;
1593 buf
&= (1 << nbits
) - 1;
1594 *dest
= (*dest
& (~0 << nbits
)) | buf
;
1600 namespace selftests
{
1602 /* Helper function for the unit test of copy_bitwise. Convert NBITS bits
1603 out of BITS, starting at OFFS, to the respective '0'/'1'-string. MSB0
1604 specifies whether to assume big endian bit numbering. Store the
1605 resulting (not null-terminated) string at STR. */
1608 bits_to_str (char *str
, const gdb_byte
*bits
, ULONGEST offs
,
1609 ULONGEST nbits
, int msb0
)
1614 for (i
= offs
/ 8, j
= offs
% 8; nbits
; i
++, j
= 0)
1616 unsigned int ch
= bits
[i
];
1617 for (; j
< 8 && nbits
; j
++, nbits
--)
1618 *str
++ = (ch
& (msb0
? (1 << (7 - j
)) : (1 << j
))) ? '1' : '0';
1622 /* Check one invocation of copy_bitwise with the given parameters. */
1625 check_copy_bitwise (const gdb_byte
*dest
, unsigned int dest_offset
,
1626 const gdb_byte
*source
, unsigned int source_offset
,
1627 unsigned int nbits
, int msb0
)
1629 size_t len
= align_up (dest_offset
+ nbits
, 8);
1630 char *expected
= (char *) alloca (len
+ 1);
1631 char *actual
= (char *) alloca (len
+ 1);
1632 gdb_byte
*buf
= (gdb_byte
*) alloca (len
/ 8);
1634 /* Compose a '0'/'1'-string that represents the expected result of
1636 Bits from [0, DEST_OFFSET) are filled from DEST.
1637 Bits from [DEST_OFFSET, DEST_OFFSET + NBITS) are filled from SOURCE.
1638 Bits from [DEST_OFFSET + NBITS, LEN) are filled from DEST.
1647 We should end up with:
1649 DDDDSSDD (D=dest, S=source)
1651 bits_to_str (expected
, dest
, 0, len
, msb0
);
1652 bits_to_str (expected
+ dest_offset
, source
, source_offset
, nbits
, msb0
);
1654 /* Fill BUF with data from DEST, apply copy_bitwise, and convert the
1655 result to a '0'/'1'-string. */
1656 memcpy (buf
, dest
, len
/ 8);
1657 copy_bitwise (buf
, dest_offset
, source
, source_offset
, nbits
, msb0
);
1658 bits_to_str (actual
, buf
, 0, len
, msb0
);
1660 /* Compare the resulting strings. */
1661 expected
[len
] = actual
[len
] = '\0';
1662 if (strcmp (expected
, actual
) != 0)
1663 error (_("copy_bitwise %s != %s (%u+%u -> %u)"),
1664 expected
, actual
, source_offset
, nbits
, dest_offset
);
1667 /* Unit test for copy_bitwise. */
1670 copy_bitwise_tests (void)
1672 /* Data to be used as both source and destination buffers. The two
1673 arrays below represent the lsb0- and msb0- encoded versions of the
1674 following bit string, respectively:
1675 00000000 00011111 11111111 01001000 10100101 11110010
1676 This pattern is chosen such that it contains:
1677 - constant 0- and 1- chunks of more than a full byte;
1678 - 0/1- and 1/0 transitions on all bit positions within a byte;
1679 - several sufficiently asymmetric bytes.
1681 static const gdb_byte data_lsb0
[] = {
1682 0x00, 0xf8, 0xff, 0x12, 0xa5, 0x4f
1684 static const gdb_byte data_msb0
[] = {
1685 0x00, 0x1f, 0xff, 0x48, 0xa5, 0xf2
1688 constexpr size_t data_nbits
= 8 * sizeof (data_lsb0
);
1689 constexpr unsigned max_nbits
= 24;
1691 /* Try all combinations of:
1692 lsb0/msb0 bit order (using the respective data array)
1693 X [0, MAX_NBITS] copy bit width
1694 X feasible source offsets for the given copy bit width
1695 X feasible destination offsets
1697 for (int msb0
= 0; msb0
< 2; msb0
++)
1699 const gdb_byte
*data
= msb0
? data_msb0
: data_lsb0
;
1701 for (unsigned int nbits
= 1; nbits
<= max_nbits
; nbits
++)
1703 const unsigned int max_offset
= data_nbits
- nbits
;
1705 for (unsigned source_offset
= 0;
1706 source_offset
<= max_offset
;
1709 for (unsigned dest_offset
= 0;
1710 dest_offset
<= max_offset
;
1713 check_copy_bitwise (data
+ dest_offset
/ 8,
1715 data
+ source_offset
/ 8,
1722 /* Special cases: copy all, copy nothing. */
1723 check_copy_bitwise (data_lsb0
, 0, data_msb0
, 0, data_nbits
, msb0
);
1724 check_copy_bitwise (data_msb0
, 0, data_lsb0
, 0, data_nbits
, msb0
);
1725 check_copy_bitwise (data
, data_nbits
- 7, data
, 9, 0, msb0
);
1729 } /* namespace selftests */
1731 #endif /* GDB_SELF_TEST */
1734 read_pieced_value (struct value
*v
)
1738 ULONGEST bits_to_skip
;
1740 struct piece_closure
*c
1741 = (struct piece_closure
*) value_computed_closure (v
);
1743 size_t buffer_size
= 0;
1744 std::vector
<gdb_byte
> buffer
;
1746 = gdbarch_bits_big_endian (get_type_arch (value_type (v
)));
1748 if (value_type (v
) != value_enclosing_type (v
))
1749 internal_error (__FILE__
, __LINE__
,
1750 _("Should not be able to create a lazy value with "
1751 "an enclosing type"));
1753 contents
= value_contents_raw (v
);
1754 bits_to_skip
= 8 * value_offset (v
);
1755 if (value_bitsize (v
))
1757 bits_to_skip
+= value_bitpos (v
);
1758 type_len
= value_bitsize (v
);
1761 type_len
= 8 * TYPE_LENGTH (value_type (v
));
1763 for (i
= 0; i
< c
->n_pieces
&& offset
< type_len
; i
++)
1765 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1766 size_t this_size
, this_size_bits
;
1767 long dest_offset_bits
, source_offset_bits
, source_offset
;
1768 const gdb_byte
*intermediate_buffer
;
1770 /* Compute size, source, and destination offsets for copying, in
1772 this_size_bits
= p
->size
;
1773 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1775 bits_to_skip
-= this_size_bits
;
1778 if (bits_to_skip
> 0)
1780 dest_offset_bits
= 0;
1781 source_offset_bits
= bits_to_skip
;
1782 this_size_bits
-= bits_to_skip
;
1787 dest_offset_bits
= offset
;
1788 source_offset_bits
= 0;
1790 if (this_size_bits
> type_len
- offset
)
1791 this_size_bits
= type_len
- offset
;
1793 this_size
= (this_size_bits
+ source_offset_bits
% 8 + 7) / 8;
1794 source_offset
= source_offset_bits
/ 8;
1795 if (buffer_size
< this_size
)
1797 buffer_size
= this_size
;
1798 buffer
.reserve (buffer_size
);
1800 intermediate_buffer
= buffer
.data ();
1802 /* Copy from the source to DEST_BUFFER. */
1803 switch (p
->location
)
1805 case DWARF_VALUE_REGISTER
:
1807 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1808 struct gdbarch
*arch
= get_frame_arch (frame
);
1809 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1811 LONGEST reg_offset
= source_offset
;
1813 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1814 && this_size
< register_size (arch
, gdb_regnum
))
1816 /* Big-endian, and we want less than full size. */
1817 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
1818 /* We want the lower-order THIS_SIZE_BITS of the bytes
1819 we extract from the register. */
1820 source_offset_bits
+= 8 * this_size
- this_size_bits
;
1823 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
1824 this_size
, buffer
.data (),
1827 /* Just so garbage doesn't ever shine through. */
1828 memset (buffer
.data (), 0, this_size
);
1831 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1833 mark_value_bits_unavailable (v
, offset
, this_size_bits
);
1838 case DWARF_VALUE_MEMORY
:
1839 read_value_memory (v
, offset
,
1840 p
->v
.mem
.in_stack_memory
,
1841 p
->v
.mem
.addr
+ source_offset
,
1842 buffer
.data (), this_size
);
1845 case DWARF_VALUE_STACK
:
1847 size_t n
= this_size
;
1849 if (n
> c
->addr_size
- source_offset
)
1850 n
= (c
->addr_size
>= source_offset
1851 ? c
->addr_size
- source_offset
1859 const gdb_byte
*val_bytes
= value_contents_all (p
->v
.value
);
1861 intermediate_buffer
= val_bytes
+ source_offset
;
1866 case DWARF_VALUE_LITERAL
:
1868 size_t n
= this_size
;
1870 if (n
> p
->v
.literal
.length
- source_offset
)
1871 n
= (p
->v
.literal
.length
>= source_offset
1872 ? p
->v
.literal
.length
- source_offset
1875 intermediate_buffer
= p
->v
.literal
.data
+ source_offset
;
1879 /* These bits show up as zeros -- but do not cause the value
1880 to be considered optimized-out. */
1881 case DWARF_VALUE_IMPLICIT_POINTER
:
1884 case DWARF_VALUE_OPTIMIZED_OUT
:
1885 mark_value_bits_optimized_out (v
, offset
, this_size_bits
);
1889 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
1892 if (p
->location
!= DWARF_VALUE_OPTIMIZED_OUT
1893 && p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
1894 copy_bitwise (contents
, dest_offset_bits
,
1895 intermediate_buffer
, source_offset_bits
% 8,
1896 this_size_bits
, bits_big_endian
);
1898 offset
+= this_size_bits
;
1903 write_pieced_value (struct value
*to
, struct value
*from
)
1907 ULONGEST bits_to_skip
;
1908 const gdb_byte
*contents
;
1909 struct piece_closure
*c
1910 = (struct piece_closure
*) value_computed_closure (to
);
1912 size_t buffer_size
= 0;
1913 std::vector
<gdb_byte
> buffer
;
1915 = gdbarch_bits_big_endian (get_type_arch (value_type (to
)));
1917 contents
= value_contents (from
);
1918 bits_to_skip
= 8 * value_offset (to
);
1919 if (value_bitsize (to
))
1921 bits_to_skip
+= value_bitpos (to
);
1922 type_len
= value_bitsize (to
);
1925 type_len
= 8 * TYPE_LENGTH (value_type (to
));
1927 for (i
= 0; i
< c
->n_pieces
&& offset
< type_len
; i
++)
1929 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
1930 size_t this_size_bits
, this_size
;
1931 long dest_offset_bits
, source_offset_bits
, dest_offset
, source_offset
;
1933 const gdb_byte
*source_buffer
;
1935 this_size_bits
= p
->size
;
1936 if (bits_to_skip
> 0 && bits_to_skip
>= this_size_bits
)
1938 bits_to_skip
-= this_size_bits
;
1941 if (this_size_bits
> type_len
- offset
)
1942 this_size_bits
= type_len
- offset
;
1943 if (bits_to_skip
> 0)
1945 dest_offset_bits
= bits_to_skip
;
1946 source_offset_bits
= 0;
1947 this_size_bits
-= bits_to_skip
;
1952 dest_offset_bits
= 0;
1953 source_offset_bits
= offset
;
1956 this_size
= (this_size_bits
+ source_offset_bits
% 8 + 7) / 8;
1957 source_offset
= source_offset_bits
/ 8;
1958 dest_offset
= dest_offset_bits
/ 8;
1959 if (dest_offset_bits
% 8 == 0 && source_offset_bits
% 8 == 0)
1961 source_buffer
= contents
+ source_offset
;
1966 if (buffer_size
< this_size
)
1968 buffer_size
= this_size
;
1969 buffer
.reserve (buffer_size
);
1971 source_buffer
= buffer
.data ();
1975 switch (p
->location
)
1977 case DWARF_VALUE_REGISTER
:
1979 struct frame_info
*frame
= frame_find_by_id (c
->frame_id
);
1980 struct gdbarch
*arch
= get_frame_arch (frame
);
1981 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, p
->v
.regno
);
1982 int reg_offset
= dest_offset
;
1984 if (gdbarch_byte_order (arch
) == BFD_ENDIAN_BIG
1985 && this_size
<= register_size (arch
, gdb_regnum
))
1987 /* Big-endian, and we want less than full size. */
1988 reg_offset
= register_size (arch
, gdb_regnum
) - this_size
;
1995 if (!get_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
1996 this_size
, buffer
.data (),
2000 throw_error (OPTIMIZED_OUT_ERROR
,
2001 _("Can't do read-modify-write to "
2002 "update bitfield; containing word "
2003 "has been optimized out"));
2005 throw_error (NOT_AVAILABLE_ERROR
,
2006 _("Can't do read-modify-write to update "
2007 "bitfield; containing word "
2010 copy_bitwise (buffer
.data (), dest_offset_bits
,
2011 contents
, source_offset_bits
,
2016 put_frame_register_bytes (frame
, gdb_regnum
, reg_offset
,
2017 this_size
, source_buffer
);
2020 case DWARF_VALUE_MEMORY
:
2023 /* Only the first and last bytes can possibly have any
2025 read_memory (p
->v
.mem
.addr
+ dest_offset
, buffer
.data (), 1);
2026 read_memory (p
->v
.mem
.addr
+ dest_offset
+ this_size
- 1,
2027 &buffer
[this_size
- 1], 1);
2028 copy_bitwise (buffer
.data (), dest_offset_bits
,
2029 contents
, source_offset_bits
,
2034 write_memory (p
->v
.mem
.addr
+ dest_offset
,
2035 source_buffer
, this_size
);
2038 mark_value_bytes_optimized_out (to
, 0, TYPE_LENGTH (value_type (to
)));
2041 offset
+= this_size_bits
;
2045 /* An implementation of an lval_funcs method to see whether a value is
2046 a synthetic pointer. */
2049 check_pieced_synthetic_pointer (const struct value
*value
, LONGEST bit_offset
,
2052 struct piece_closure
*c
2053 = (struct piece_closure
*) value_computed_closure (value
);
2056 bit_offset
+= 8 * value_offset (value
);
2057 if (value_bitsize (value
))
2058 bit_offset
+= value_bitpos (value
);
2060 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2062 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2063 size_t this_size_bits
= p
->size
;
2067 if (bit_offset
>= this_size_bits
)
2069 bit_offset
-= this_size_bits
;
2073 bit_length
-= this_size_bits
- bit_offset
;
2077 bit_length
-= this_size_bits
;
2079 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2086 /* A wrapper function for get_frame_address_in_block. */
2089 get_frame_address_in_block_wrapper (void *baton
)
2091 return get_frame_address_in_block ((struct frame_info
*) baton
);
2094 /* Fetch a DW_AT_const_value through a synthetic pointer. */
2096 static struct value
*
2097 fetch_const_value_from_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2098 struct dwarf2_per_cu_data
*per_cu
,
2101 struct value
*result
= NULL
;
2102 struct obstack temp_obstack
;
2103 struct cleanup
*cleanup
;
2104 const gdb_byte
*bytes
;
2107 obstack_init (&temp_obstack
);
2108 cleanup
= make_cleanup_obstack_free (&temp_obstack
);
2109 bytes
= dwarf2_fetch_constant_bytes (die
, per_cu
, &temp_obstack
, &len
);
2113 if (byte_offset
>= 0
2114 && byte_offset
+ TYPE_LENGTH (TYPE_TARGET_TYPE (type
)) <= len
)
2116 bytes
+= byte_offset
;
2117 result
= value_from_contents (TYPE_TARGET_TYPE (type
), bytes
);
2120 invalid_synthetic_pointer ();
2123 result
= allocate_optimized_out_value (TYPE_TARGET_TYPE (type
));
2125 do_cleanups (cleanup
);
2130 /* Fetch the value pointed to by a synthetic pointer. */
2132 static struct value
*
2133 indirect_synthetic_pointer (sect_offset die
, LONGEST byte_offset
,
2134 struct dwarf2_per_cu_data
*per_cu
,
2135 struct frame_info
*frame
, struct type
*type
)
2137 /* Fetch the location expression of the DIE we're pointing to. */
2138 struct dwarf2_locexpr_baton baton
2139 = dwarf2_fetch_die_loc_sect_off (die
, per_cu
,
2140 get_frame_address_in_block_wrapper
, frame
);
2142 /* If pointed-to DIE has a DW_AT_location, evaluate it and return the
2143 resulting value. Otherwise, it may have a DW_AT_const_value instead,
2144 or it may've been optimized out. */
2145 if (baton
.data
!= NULL
)
2146 return dwarf2_evaluate_loc_desc_full (TYPE_TARGET_TYPE (type
), frame
,
2147 baton
.data
, baton
.size
, baton
.per_cu
,
2150 return fetch_const_value_from_synthetic_pointer (die
, byte_offset
, per_cu
,
2154 /* An implementation of an lval_funcs method to indirect through a
2155 pointer. This handles the synthetic pointer case when needed. */
2157 static struct value
*
2158 indirect_pieced_value (struct value
*value
)
2160 struct piece_closure
*c
2161 = (struct piece_closure
*) value_computed_closure (value
);
2163 struct frame_info
*frame
;
2164 struct dwarf2_locexpr_baton baton
;
2167 struct dwarf_expr_piece
*piece
= NULL
;
2168 LONGEST byte_offset
;
2169 enum bfd_endian byte_order
;
2171 type
= check_typedef (value_type (value
));
2172 if (TYPE_CODE (type
) != TYPE_CODE_PTR
)
2175 bit_length
= 8 * TYPE_LENGTH (type
);
2176 bit_offset
= 8 * value_offset (value
);
2177 if (value_bitsize (value
))
2178 bit_offset
+= value_bitpos (value
);
2180 for (i
= 0; i
< c
->n_pieces
&& bit_length
> 0; i
++)
2182 struct dwarf_expr_piece
*p
= &c
->pieces
[i
];
2183 size_t this_size_bits
= p
->size
;
2187 if (bit_offset
>= this_size_bits
)
2189 bit_offset
-= this_size_bits
;
2193 bit_length
-= this_size_bits
- bit_offset
;
2197 bit_length
-= this_size_bits
;
2199 if (p
->location
!= DWARF_VALUE_IMPLICIT_POINTER
)
2202 if (bit_length
!= 0)
2203 error (_("Invalid use of DW_OP_GNU_implicit_pointer"));
2209 gdb_assert (piece
!= NULL
);
2210 frame
= get_selected_frame (_("No frame selected."));
2212 /* This is an offset requested by GDB, such as value subscripts.
2213 However, due to how synthetic pointers are implemented, this is
2214 always presented to us as a pointer type. This means we have to
2215 sign-extend it manually as appropriate. Use raw
2216 extract_signed_integer directly rather than value_as_address and
2217 sign extend afterwards on architectures that would need it
2218 (mostly everywhere except MIPS, which has signed addresses) as
2219 the later would go through gdbarch_pointer_to_address and thus
2220 return a CORE_ADDR with high bits set on architectures that
2221 encode address spaces and other things in CORE_ADDR. */
2222 byte_order
= gdbarch_byte_order (get_frame_arch (frame
));
2223 byte_offset
= extract_signed_integer (value_contents (value
),
2224 TYPE_LENGTH (type
), byte_order
);
2225 byte_offset
+= piece
->v
.ptr
.offset
;
2227 return indirect_synthetic_pointer (piece
->v
.ptr
.die
, byte_offset
, c
->per_cu
,
2231 /* Implementation of the coerce_ref method of lval_funcs for synthetic C++
2234 static struct value
*
2235 coerce_pieced_ref (const struct value
*value
)
2237 struct type
*type
= check_typedef (value_type (value
));
2239 if (value_bits_synthetic_pointer (value
, value_embedded_offset (value
),
2240 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
2242 const struct piece_closure
*closure
2243 = (struct piece_closure
*) value_computed_closure (value
);
2244 struct frame_info
*frame
2245 = get_selected_frame (_("No frame selected."));
2247 /* gdb represents synthetic pointers as pieced values with a single
2249 gdb_assert (closure
!= NULL
);
2250 gdb_assert (closure
->n_pieces
== 1);
2252 return indirect_synthetic_pointer (closure
->pieces
->v
.ptr
.die
,
2253 closure
->pieces
->v
.ptr
.offset
,
2254 closure
->per_cu
, frame
, type
);
2258 /* Else: not a synthetic reference; do nothing. */
2264 copy_pieced_value_closure (const struct value
*v
)
2266 struct piece_closure
*c
2267 = (struct piece_closure
*) value_computed_closure (v
);
2274 free_pieced_value_closure (struct value
*v
)
2276 struct piece_closure
*c
2277 = (struct piece_closure
*) value_computed_closure (v
);
2284 for (i
= 0; i
< c
->n_pieces
; ++i
)
2285 if (c
->pieces
[i
].location
== DWARF_VALUE_STACK
)
2286 value_free (c
->pieces
[i
].v
.value
);
2293 /* Functions for accessing a variable described by DW_OP_piece. */
2294 static const struct lval_funcs pieced_value_funcs
= {
2297 indirect_pieced_value
,
2299 check_pieced_synthetic_pointer
,
2300 copy_pieced_value_closure
,
2301 free_pieced_value_closure
2304 /* Evaluate a location description, starting at DATA and with length
2305 SIZE, to find the current location of variable of TYPE in the
2306 context of FRAME. BYTE_OFFSET is applied after the contents are
2309 static struct value
*
2310 dwarf2_evaluate_loc_desc_full (struct type
*type
, struct frame_info
*frame
,
2311 const gdb_byte
*data
, size_t size
,
2312 struct dwarf2_per_cu_data
*per_cu
,
2313 LONGEST byte_offset
)
2315 struct value
*retval
;
2316 struct cleanup
*value_chain
;
2317 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2319 if (byte_offset
< 0)
2320 invalid_synthetic_pointer ();
2323 return allocate_optimized_out_value (type
);
2325 dwarf_evaluate_loc_desc ctx
;
2327 ctx
.per_cu
= per_cu
;
2328 ctx
.obj_address
= 0;
2330 value_chain
= make_cleanup_value_free_to_mark (value_mark ());
2332 ctx
.gdbarch
= get_objfile_arch (objfile
);
2333 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2334 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2335 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2339 ctx
.eval (data
, size
);
2341 CATCH (ex
, RETURN_MASK_ERROR
)
2343 if (ex
.error
== NOT_AVAILABLE_ERROR
)
2345 do_cleanups (value_chain
);
2346 retval
= allocate_value (type
);
2347 mark_value_bytes_unavailable (retval
, 0, TYPE_LENGTH (type
));
2350 else if (ex
.error
== NO_ENTRY_VALUE_ERROR
)
2352 if (entry_values_debug
)
2353 exception_print (gdb_stdout
, ex
);
2354 do_cleanups (value_chain
);
2355 return allocate_optimized_out_value (type
);
2358 throw_exception (ex
);
2362 if (ctx
.num_pieces
> 0)
2364 struct piece_closure
*c
;
2365 ULONGEST bit_size
= 0;
2368 for (i
= 0; i
< ctx
.num_pieces
; ++i
)
2369 bit_size
+= ctx
.pieces
[i
].size
;
2370 if (8 * (byte_offset
+ TYPE_LENGTH (type
)) > bit_size
)
2371 invalid_synthetic_pointer ();
2373 c
= allocate_piece_closure (per_cu
, ctx
.num_pieces
, ctx
.pieces
,
2374 ctx
.addr_size
, frame
);
2375 /* We must clean up the value chain after creating the piece
2376 closure but before allocating the result. */
2377 do_cleanups (value_chain
);
2378 retval
= allocate_computed_value (type
, &pieced_value_funcs
, c
);
2379 set_value_offset (retval
, byte_offset
);
2383 switch (ctx
.location
)
2385 case DWARF_VALUE_REGISTER
:
2387 struct gdbarch
*arch
= get_frame_arch (frame
);
2389 = longest_to_int (value_as_long (ctx
.fetch (0)));
2390 int gdb_regnum
= dwarf_reg_to_regnum_or_error (arch
, dwarf_regnum
);
2392 if (byte_offset
!= 0)
2393 error (_("cannot use offset on synthetic pointer to register"));
2394 do_cleanups (value_chain
);
2395 retval
= value_from_register (type
, gdb_regnum
, frame
);
2396 if (value_optimized_out (retval
))
2400 /* This means the register has undefined value / was
2401 not saved. As we're computing the location of some
2402 variable etc. in the program, not a value for
2403 inspecting a register ($pc, $sp, etc.), return a
2404 generic optimized out value instead, so that we show
2405 <optimized out> instead of <not saved>. */
2406 do_cleanups (value_chain
);
2407 tmp
= allocate_value (type
);
2408 value_contents_copy (tmp
, 0, retval
, 0, TYPE_LENGTH (type
));
2414 case DWARF_VALUE_MEMORY
:
2416 struct type
*ptr_type
;
2417 CORE_ADDR address
= ctx
.fetch_address (0);
2418 int in_stack_memory
= ctx
.fetch_in_stack_memory (0);
2420 /* DW_OP_deref_size (and possibly other operations too) may
2421 create a pointer instead of an address. Ideally, the
2422 pointer to address conversion would be performed as part
2423 of those operations, but the type of the object to
2424 which the address refers is not known at the time of
2425 the operation. Therefore, we do the conversion here
2426 since the type is readily available. */
2428 switch (TYPE_CODE (type
))
2430 case TYPE_CODE_FUNC
:
2431 case TYPE_CODE_METHOD
:
2432 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_func_ptr
;
2435 ptr_type
= builtin_type (ctx
.gdbarch
)->builtin_data_ptr
;
2438 address
= value_as_address (value_from_pointer (ptr_type
, address
));
2440 do_cleanups (value_chain
);
2441 retval
= value_at_lazy (type
, address
+ byte_offset
);
2442 if (in_stack_memory
)
2443 set_value_stack (retval
, 1);
2447 case DWARF_VALUE_STACK
:
2449 struct value
*value
= ctx
.fetch (0);
2451 const gdb_byte
*val_bytes
;
2452 size_t n
= TYPE_LENGTH (value_type (value
));
2454 if (byte_offset
+ TYPE_LENGTH (type
) > n
)
2455 invalid_synthetic_pointer ();
2457 val_bytes
= value_contents_all (value
);
2458 val_bytes
+= byte_offset
;
2461 /* Preserve VALUE because we are going to free values back
2462 to the mark, but we still need the value contents
2464 value_incref (value
);
2465 do_cleanups (value_chain
);
2466 make_cleanup_value_free (value
);
2468 retval
= allocate_value (type
);
2469 contents
= value_contents_raw (retval
);
2470 if (n
> TYPE_LENGTH (type
))
2472 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2474 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2475 val_bytes
+= n
- TYPE_LENGTH (type
);
2476 n
= TYPE_LENGTH (type
);
2478 memcpy (contents
, val_bytes
, n
);
2482 case DWARF_VALUE_LITERAL
:
2485 const bfd_byte
*ldata
;
2488 if (byte_offset
+ TYPE_LENGTH (type
) > n
)
2489 invalid_synthetic_pointer ();
2491 do_cleanups (value_chain
);
2492 retval
= allocate_value (type
);
2493 contents
= value_contents_raw (retval
);
2495 ldata
= ctx
.data
+ byte_offset
;
2498 if (n
> TYPE_LENGTH (type
))
2500 struct gdbarch
*objfile_gdbarch
= get_objfile_arch (objfile
);
2502 if (gdbarch_byte_order (objfile_gdbarch
) == BFD_ENDIAN_BIG
)
2503 ldata
+= n
- TYPE_LENGTH (type
);
2504 n
= TYPE_LENGTH (type
);
2506 memcpy (contents
, ldata
, n
);
2510 case DWARF_VALUE_OPTIMIZED_OUT
:
2511 do_cleanups (value_chain
);
2512 retval
= allocate_optimized_out_value (type
);
2515 /* DWARF_VALUE_IMPLICIT_POINTER was converted to a pieced
2516 operation by execute_stack_op. */
2517 case DWARF_VALUE_IMPLICIT_POINTER
:
2518 /* DWARF_VALUE_OPTIMIZED_OUT can't occur in this context --
2519 it can only be encountered when making a piece. */
2521 internal_error (__FILE__
, __LINE__
, _("invalid location type"));
2525 set_value_initialized (retval
, ctx
.initialized
);
2527 do_cleanups (value_chain
);
2532 /* The exported interface to dwarf2_evaluate_loc_desc_full; it always
2533 passes 0 as the byte_offset. */
2536 dwarf2_evaluate_loc_desc (struct type
*type
, struct frame_info
*frame
,
2537 const gdb_byte
*data
, size_t size
,
2538 struct dwarf2_per_cu_data
*per_cu
)
2540 return dwarf2_evaluate_loc_desc_full (type
, frame
, data
, size
, per_cu
, 0);
2543 /* Evaluates a dwarf expression and stores the result in VAL, expecting
2544 that the dwarf expression only produces a single CORE_ADDR. FRAME is the
2545 frame in which the expression is evaluated. ADDR is a context (location of
2546 a variable) and might be needed to evaluate the location expression.
2547 Returns 1 on success, 0 otherwise. */
2550 dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton
*dlbaton
,
2551 struct frame_info
*frame
,
2555 struct objfile
*objfile
;
2556 struct cleanup
*cleanup
;
2558 if (dlbaton
== NULL
|| dlbaton
->size
== 0)
2561 dwarf_evaluate_loc_desc ctx
;
2564 ctx
.per_cu
= dlbaton
->per_cu
;
2565 ctx
.obj_address
= addr
;
2567 objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
2569 ctx
.gdbarch
= get_objfile_arch (objfile
);
2570 ctx
.addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
2571 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (dlbaton
->per_cu
);
2572 ctx
.offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
2574 ctx
.eval (dlbaton
->data
, dlbaton
->size
);
2576 switch (ctx
.location
)
2578 case DWARF_VALUE_REGISTER
:
2579 case DWARF_VALUE_MEMORY
:
2580 case DWARF_VALUE_STACK
:
2581 *valp
= ctx
.fetch_address (0);
2582 if (ctx
.location
== DWARF_VALUE_REGISTER
)
2583 *valp
= ctx
.read_addr_from_reg (*valp
);
2585 case DWARF_VALUE_LITERAL
:
2586 *valp
= extract_signed_integer (ctx
.data
, ctx
.len
,
2587 gdbarch_byte_order (ctx
.gdbarch
));
2589 /* Unsupported dwarf values. */
2590 case DWARF_VALUE_OPTIMIZED_OUT
:
2591 case DWARF_VALUE_IMPLICIT_POINTER
:
2598 /* See dwarf2loc.h. */
2601 dwarf2_evaluate_property (const struct dynamic_prop
*prop
,
2602 struct frame_info
*frame
,
2603 struct property_addr_info
*addr_stack
,
2609 if (frame
== NULL
&& has_stack_frames ())
2610 frame
= get_selected_frame (NULL
);
2616 const struct dwarf2_property_baton
*baton
2617 = (const struct dwarf2_property_baton
*) prop
->data
.baton
;
2619 if (dwarf2_locexpr_baton_eval (&baton
->locexpr
, frame
,
2620 addr_stack
? addr_stack
->addr
: 0,
2623 if (baton
->referenced_type
)
2625 struct value
*val
= value_at (baton
->referenced_type
, *value
);
2627 *value
= value_as_address (val
);
2636 struct dwarf2_property_baton
*baton
2637 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2638 CORE_ADDR pc
= get_frame_address_in_block (frame
);
2639 const gdb_byte
*data
;
2643 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2646 val
= dwarf2_evaluate_loc_desc (baton
->referenced_type
, frame
, data
,
2647 size
, baton
->loclist
.per_cu
);
2648 if (!value_optimized_out (val
))
2650 *value
= value_as_address (val
);
2658 *value
= prop
->data
.const_val
;
2661 case PROP_ADDR_OFFSET
:
2663 struct dwarf2_property_baton
*baton
2664 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2665 struct property_addr_info
*pinfo
;
2668 for (pinfo
= addr_stack
; pinfo
!= NULL
; pinfo
= pinfo
->next
)
2669 if (pinfo
->type
== baton
->referenced_type
)
2672 error (_("cannot find reference address for offset property"));
2673 if (pinfo
->valaddr
!= NULL
)
2674 val
= value_from_contents
2675 (baton
->offset_info
.type
,
2676 pinfo
->valaddr
+ baton
->offset_info
.offset
);
2678 val
= value_at (baton
->offset_info
.type
,
2679 pinfo
->addr
+ baton
->offset_info
.offset
);
2680 *value
= value_as_address (val
);
2688 /* See dwarf2loc.h. */
2691 dwarf2_compile_property_to_c (struct ui_file
*stream
,
2692 const char *result_name
,
2693 struct gdbarch
*gdbarch
,
2694 unsigned char *registers_used
,
2695 const struct dynamic_prop
*prop
,
2699 struct dwarf2_property_baton
*baton
2700 = (struct dwarf2_property_baton
*) prop
->data
.baton
;
2701 const gdb_byte
*data
;
2703 struct dwarf2_per_cu_data
*per_cu
;
2705 if (prop
->kind
== PROP_LOCEXPR
)
2707 data
= baton
->locexpr
.data
;
2708 size
= baton
->locexpr
.size
;
2709 per_cu
= baton
->locexpr
.per_cu
;
2713 gdb_assert (prop
->kind
== PROP_LOCLIST
);
2715 data
= dwarf2_find_location_expression (&baton
->loclist
, &size
, pc
);
2716 per_cu
= baton
->loclist
.per_cu
;
2719 compile_dwarf_bounds_to_c (stream
, result_name
, prop
, sym
, pc
,
2720 gdbarch
, registers_used
,
2721 dwarf2_per_cu_addr_size (per_cu
),
2722 data
, data
+ size
, per_cu
);
2726 /* Helper functions and baton for dwarf2_loc_desc_get_symbol_read_needs. */
2728 class symbol_needs_eval_context
: public dwarf_expr_context
2732 enum symbol_needs_kind needs
;
2733 struct dwarf2_per_cu_data
*per_cu
;
2735 /* Reads from registers do require a frame. */
2736 CORE_ADDR
read_addr_from_reg (int regnum
) OVERRIDE
2738 needs
= SYMBOL_NEEDS_FRAME
;
2742 /* "get_reg_value" callback: Reads from registers do require a
2745 struct value
*get_reg_value (struct type
*type
, int regnum
) OVERRIDE
2747 needs
= SYMBOL_NEEDS_FRAME
;
2748 return value_zero (type
, not_lval
);
2751 /* Reads from memory do not require a frame. */
2752 void read_mem (gdb_byte
*buf
, CORE_ADDR addr
, size_t len
) OVERRIDE
2754 memset (buf
, 0, len
);
2757 /* Frame-relative accesses do require a frame. */
2758 void get_frame_base (const gdb_byte
**start
, size_t *length
) OVERRIDE
2760 static gdb_byte lit0
= DW_OP_lit0
;
2765 needs
= SYMBOL_NEEDS_FRAME
;
2768 /* CFA accesses require a frame. */
2769 CORE_ADDR
get_frame_cfa () OVERRIDE
2771 needs
= SYMBOL_NEEDS_FRAME
;
2775 CORE_ADDR
get_frame_pc () OVERRIDE
2777 needs
= SYMBOL_NEEDS_FRAME
;
2781 /* Thread-local accesses require registers, but not a frame. */
2782 CORE_ADDR
get_tls_address (CORE_ADDR offset
) OVERRIDE
2784 if (needs
<= SYMBOL_NEEDS_REGISTERS
)
2785 needs
= SYMBOL_NEEDS_REGISTERS
;
2789 /* Helper interface of per_cu_dwarf_call for
2790 dwarf2_loc_desc_get_symbol_read_needs. */
2792 void dwarf_call (cu_offset die_offset
) OVERRIDE
2794 per_cu_dwarf_call (this, die_offset
, per_cu
);
2797 /* DW_OP_GNU_entry_value accesses require a caller, therefore a
2800 void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind
,
2801 union call_site_parameter_u kind_u
,
2802 int deref_size
) OVERRIDE
2804 needs
= SYMBOL_NEEDS_FRAME
;
2806 /* The expression may require some stub values on DWARF stack. */
2807 push_address (0, 0);
2810 /* DW_OP_GNU_addr_index doesn't require a frame. */
2812 CORE_ADDR
get_addr_index (unsigned int index
) OVERRIDE
2814 /* Nothing to do. */
2818 /* DW_OP_push_object_address has a frame already passed through. */
2820 CORE_ADDR
get_object_address () OVERRIDE
2822 /* Nothing to do. */
2827 /* Compute the correct symbol_needs_kind value for the location
2828 expression at DATA (length SIZE). */
2830 static enum symbol_needs_kind
2831 dwarf2_loc_desc_get_symbol_read_needs (const gdb_byte
*data
, size_t size
,
2832 struct dwarf2_per_cu_data
*per_cu
)
2835 struct cleanup
*old_chain
;
2836 struct objfile
*objfile
= dwarf2_per_cu_objfile (per_cu
);
2838 symbol_needs_eval_context ctx
;
2840 ctx
.needs
= SYMBOL_NEEDS_NONE
;
2841 ctx
.per_cu
= per_cu
;
2843 old_chain
= make_cleanup_value_free_to_mark (value_mark ());
2845 ctx
.gdbarch
= get_objfile_arch (objfile
);
2846 ctx
.addr_size
= dwarf2_per_cu_addr_size (per_cu
);
2847 ctx
.ref_addr_size
= dwarf2_per_cu_ref_addr_size (per_cu
);
2848 ctx
.offset
= dwarf2_per_cu_text_offset (per_cu
);
2850 ctx
.eval (data
, size
);
2852 in_reg
= ctx
.location
== DWARF_VALUE_REGISTER
;
2854 if (ctx
.num_pieces
> 0)
2858 /* If the location has several pieces, and any of them are in
2859 registers, then we will need a frame to fetch them from. */
2860 for (i
= 0; i
< ctx
.num_pieces
; i
++)
2861 if (ctx
.pieces
[i
].location
== DWARF_VALUE_REGISTER
)
2865 do_cleanups (old_chain
);
2868 ctx
.needs
= SYMBOL_NEEDS_FRAME
;
2872 /* A helper function that throws an unimplemented error mentioning a
2873 given DWARF operator. */
2876 unimplemented (unsigned int op
)
2878 const char *name
= get_DW_OP_name (op
);
2881 error (_("DWARF operator %s cannot be translated to an agent expression"),
2884 error (_("Unknown DWARF operator 0x%02x cannot be translated "
2885 "to an agent expression"),
2891 This is basically a wrapper on gdbarch_dwarf2_reg_to_regnum so that we
2892 can issue a complaint, which is better than having every target's
2893 implementation of dwarf2_reg_to_regnum do it. */
2896 dwarf_reg_to_regnum (struct gdbarch
*arch
, int dwarf_reg
)
2898 int reg
= gdbarch_dwarf2_reg_to_regnum (arch
, dwarf_reg
);
2902 complaint (&symfile_complaints
,
2903 _("bad DWARF register number %d"), dwarf_reg
);
2908 /* Subroutine of dwarf_reg_to_regnum_or_error to simplify it.
2909 Throw an error because DWARF_REG is bad. */
2912 throw_bad_regnum_error (ULONGEST dwarf_reg
)
2914 /* Still want to print -1 as "-1".
2915 We *could* have int and ULONGEST versions of dwarf2_reg_to_regnum_or_error
2916 but that's overkill for now. */
2917 if ((int) dwarf_reg
== dwarf_reg
)
2918 error (_("Unable to access DWARF register number %d"), (int) dwarf_reg
);
2919 error (_("Unable to access DWARF register number %s"),
2920 pulongest (dwarf_reg
));
2923 /* See dwarf2loc.h. */
2926 dwarf_reg_to_regnum_or_error (struct gdbarch
*arch
, ULONGEST dwarf_reg
)
2930 if (dwarf_reg
> INT_MAX
)
2931 throw_bad_regnum_error (dwarf_reg
);
2932 /* Yes, we will end up issuing a complaint and an error if DWARF_REG is
2933 bad, but that's ok. */
2934 reg
= dwarf_reg_to_regnum (arch
, (int) dwarf_reg
);
2936 throw_bad_regnum_error (dwarf_reg
);
2940 /* A helper function that emits an access to memory. ARCH is the
2941 target architecture. EXPR is the expression which we are building.
2942 NBITS is the number of bits we want to read. This emits the
2943 opcodes needed to read the memory and then extract the desired
2947 access_memory (struct gdbarch
*arch
, struct agent_expr
*expr
, ULONGEST nbits
)
2949 ULONGEST nbytes
= (nbits
+ 7) / 8;
2951 gdb_assert (nbytes
> 0 && nbytes
<= sizeof (LONGEST
));
2954 ax_trace_quick (expr
, nbytes
);
2957 ax_simple (expr
, aop_ref8
);
2958 else if (nbits
<= 16)
2959 ax_simple (expr
, aop_ref16
);
2960 else if (nbits
<= 32)
2961 ax_simple (expr
, aop_ref32
);
2963 ax_simple (expr
, aop_ref64
);
2965 /* If we read exactly the number of bytes we wanted, we're done. */
2966 if (8 * nbytes
== nbits
)
2969 if (gdbarch_bits_big_endian (arch
))
2971 /* On a bits-big-endian machine, we want the high-order
2973 ax_const_l (expr
, 8 * nbytes
- nbits
);
2974 ax_simple (expr
, aop_rsh_unsigned
);
2978 /* On a bits-little-endian box, we want the low-order NBITS. */
2979 ax_zero_ext (expr
, nbits
);
2983 /* A helper function to return the frame's PC. */
2986 get_ax_pc (void *baton
)
2988 struct agent_expr
*expr
= (struct agent_expr
*) baton
;
2993 /* Compile a DWARF location expression to an agent expression.
2995 EXPR is the agent expression we are building.
2996 LOC is the agent value we modify.
2997 ARCH is the architecture.
2998 ADDR_SIZE is the size of addresses, in bytes.
2999 OP_PTR is the start of the location expression.
3000 OP_END is one past the last byte of the location expression.
3002 This will throw an exception for various kinds of errors -- for
3003 example, if the expression cannot be compiled, or if the expression
3007 dwarf2_compile_expr_to_ax (struct agent_expr
*expr
, struct axs_value
*loc
,
3008 struct gdbarch
*arch
, unsigned int addr_size
,
3009 const gdb_byte
*op_ptr
, const gdb_byte
*op_end
,
3010 struct dwarf2_per_cu_data
*per_cu
)
3013 std::vector
<int> dw_labels
, patches
;
3014 const gdb_byte
* const base
= op_ptr
;
3015 const gdb_byte
*previous_piece
= op_ptr
;
3016 enum bfd_endian byte_order
= gdbarch_byte_order (arch
);
3017 ULONGEST bits_collected
= 0;
3018 unsigned int addr_size_bits
= 8 * addr_size
;
3019 int bits_big_endian
= gdbarch_bits_big_endian (arch
);
3021 std::vector
<int> offsets (op_end
- op_ptr
, -1);
3023 /* By default we are making an address. */
3024 loc
->kind
= axs_lvalue_memory
;
3026 while (op_ptr
< op_end
)
3028 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *op_ptr
;
3029 uint64_t uoffset
, reg
;
3033 offsets
[op_ptr
- base
] = expr
->len
;
3036 /* Our basic approach to code generation is to map DWARF
3037 operations directly to AX operations. However, there are
3040 First, DWARF works on address-sized units, but AX always uses
3041 LONGEST. For most operations we simply ignore this
3042 difference; instead we generate sign extensions as needed
3043 before division and comparison operations. It would be nice
3044 to omit the sign extensions, but there is no way to determine
3045 the size of the target's LONGEST. (This code uses the size
3046 of the host LONGEST in some cases -- that is a bug but it is
3049 Second, some DWARF operations cannot be translated to AX.
3050 For these we simply fail. See
3051 http://sourceware.org/bugzilla/show_bug.cgi?id=11662. */
3086 ax_const_l (expr
, op
- DW_OP_lit0
);
3090 uoffset
= extract_unsigned_integer (op_ptr
, addr_size
, byte_order
);
3091 op_ptr
+= addr_size
;
3092 /* Some versions of GCC emit DW_OP_addr before
3093 DW_OP_GNU_push_tls_address. In this case the value is an
3094 index, not an address. We don't support things like
3095 branching between the address and the TLS op. */
3096 if (op_ptr
>= op_end
|| *op_ptr
!= DW_OP_GNU_push_tls_address
)
3097 uoffset
+= dwarf2_per_cu_text_offset (per_cu
);
3098 ax_const_l (expr
, uoffset
);
3102 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 1, byte_order
));
3106 ax_const_l (expr
, extract_signed_integer (op_ptr
, 1, byte_order
));
3110 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 2, byte_order
));
3114 ax_const_l (expr
, extract_signed_integer (op_ptr
, 2, byte_order
));
3118 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 4, byte_order
));
3122 ax_const_l (expr
, extract_signed_integer (op_ptr
, 4, byte_order
));
3126 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, 8, byte_order
));
3130 ax_const_l (expr
, extract_signed_integer (op_ptr
, 8, byte_order
));
3134 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &uoffset
);
3135 ax_const_l (expr
, uoffset
);
3138 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3139 ax_const_l (expr
, offset
);
3174 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3175 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_reg0
);
3176 loc
->kind
= axs_lvalue_register
;
3180 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3181 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_regx");
3182 loc
->u
.reg
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3183 loc
->kind
= axs_lvalue_register
;
3186 case DW_OP_implicit_value
:
3190 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &len
);
3191 if (op_ptr
+ len
> op_end
)
3192 error (_("DW_OP_implicit_value: too few bytes available."));
3193 if (len
> sizeof (ULONGEST
))
3194 error (_("Cannot translate DW_OP_implicit_value of %d bytes"),
3197 ax_const_l (expr
, extract_unsigned_integer (op_ptr
, len
,
3200 dwarf_expr_require_composition (op_ptr
, op_end
,
3201 "DW_OP_implicit_value");
3203 loc
->kind
= axs_rvalue
;
3207 case DW_OP_stack_value
:
3208 dwarf_expr_require_composition (op_ptr
, op_end
, "DW_OP_stack_value");
3209 loc
->kind
= axs_rvalue
;
3244 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3245 i
= dwarf_reg_to_regnum_or_error (arch
, op
- DW_OP_breg0
);
3249 ax_const_l (expr
, offset
);
3250 ax_simple (expr
, aop_add
);
3255 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3256 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3257 i
= dwarf_reg_to_regnum_or_error (arch
, reg
);
3261 ax_const_l (expr
, offset
);
3262 ax_simple (expr
, aop_add
);
3268 const gdb_byte
*datastart
;
3270 const struct block
*b
;
3271 struct symbol
*framefunc
;
3273 b
= block_for_pc (expr
->scope
);
3276 error (_("No block found for address"));
3278 framefunc
= block_linkage_function (b
);
3281 error (_("No function found for block"));
3283 func_get_frame_base_dwarf_block (framefunc
, expr
->scope
,
3284 &datastart
, &datalen
);
3286 op_ptr
= safe_read_sleb128 (op_ptr
, op_end
, &offset
);
3287 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
, datastart
,
3288 datastart
+ datalen
, per_cu
);
3289 if (loc
->kind
== axs_lvalue_register
)
3290 require_rvalue (expr
, loc
);
3294 ax_const_l (expr
, offset
);
3295 ax_simple (expr
, aop_add
);
3298 loc
->kind
= axs_lvalue_memory
;
3303 ax_simple (expr
, aop_dup
);
3307 ax_simple (expr
, aop_pop
);
3312 ax_pick (expr
, offset
);
3316 ax_simple (expr
, aop_swap
);
3324 ax_simple (expr
, aop_rot
);
3328 case DW_OP_deref_size
:
3332 if (op
== DW_OP_deref_size
)
3337 if (size
!= 1 && size
!= 2 && size
!= 4 && size
!= 8)
3338 error (_("Unsupported size %d in %s"),
3339 size
, get_DW_OP_name (op
));
3340 access_memory (arch
, expr
, size
* TARGET_CHAR_BIT
);
3345 /* Sign extend the operand. */
3346 ax_ext (expr
, addr_size_bits
);
3347 ax_simple (expr
, aop_dup
);
3348 ax_const_l (expr
, 0);
3349 ax_simple (expr
, aop_less_signed
);
3350 ax_simple (expr
, aop_log_not
);
3351 i
= ax_goto (expr
, aop_if_goto
);
3352 /* We have to emit 0 - X. */
3353 ax_const_l (expr
, 0);
3354 ax_simple (expr
, aop_swap
);
3355 ax_simple (expr
, aop_sub
);
3356 ax_label (expr
, i
, expr
->len
);
3360 /* No need to sign extend here. */
3361 ax_const_l (expr
, 0);
3362 ax_simple (expr
, aop_swap
);
3363 ax_simple (expr
, aop_sub
);
3367 /* Sign extend the operand. */
3368 ax_ext (expr
, addr_size_bits
);
3369 ax_simple (expr
, aop_bit_not
);
3372 case DW_OP_plus_uconst
:
3373 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, ®
);
3374 /* It would be really weird to emit `DW_OP_plus_uconst 0',
3375 but we micro-optimize anyhow. */
3378 ax_const_l (expr
, reg
);
3379 ax_simple (expr
, aop_add
);
3384 ax_simple (expr
, aop_bit_and
);
3388 /* Sign extend the operands. */
3389 ax_ext (expr
, addr_size_bits
);
3390 ax_simple (expr
, aop_swap
);
3391 ax_ext (expr
, addr_size_bits
);
3392 ax_simple (expr
, aop_swap
);
3393 ax_simple (expr
, aop_div_signed
);
3397 ax_simple (expr
, aop_sub
);
3401 ax_simple (expr
, aop_rem_unsigned
);
3405 ax_simple (expr
, aop_mul
);
3409 ax_simple (expr
, aop_bit_or
);
3413 ax_simple (expr
, aop_add
);
3417 ax_simple (expr
, aop_lsh
);
3421 ax_simple (expr
, aop_rsh_unsigned
);
3425 ax_simple (expr
, aop_rsh_signed
);
3429 ax_simple (expr
, aop_bit_xor
);
3433 /* Sign extend the operands. */
3434 ax_ext (expr
, addr_size_bits
);
3435 ax_simple (expr
, aop_swap
);
3436 ax_ext (expr
, addr_size_bits
);
3437 /* Note no swap here: A <= B is !(B < A). */
3438 ax_simple (expr
, aop_less_signed
);
3439 ax_simple (expr
, aop_log_not
);
3443 /* Sign extend the operands. */
3444 ax_ext (expr
, addr_size_bits
);
3445 ax_simple (expr
, aop_swap
);
3446 ax_ext (expr
, addr_size_bits
);
3447 ax_simple (expr
, aop_swap
);
3448 /* A >= B is !(A < B). */
3449 ax_simple (expr
, aop_less_signed
);
3450 ax_simple (expr
, aop_log_not
);
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 /* No need for a second swap here. */
3459 ax_simple (expr
, aop_equal
);
3463 /* Sign extend the operands. */
3464 ax_ext (expr
, addr_size_bits
);
3465 ax_simple (expr
, aop_swap
);
3466 ax_ext (expr
, addr_size_bits
);
3467 ax_simple (expr
, aop_swap
);
3468 ax_simple (expr
, aop_less_signed
);
3472 /* Sign extend the operands. */
3473 ax_ext (expr
, addr_size_bits
);
3474 ax_simple (expr
, aop_swap
);
3475 ax_ext (expr
, addr_size_bits
);
3476 /* Note no swap here: A > B is B < A. */
3477 ax_simple (expr
, aop_less_signed
);
3481 /* Sign extend the operands. */
3482 ax_ext (expr
, addr_size_bits
);
3483 ax_simple (expr
, aop_swap
);
3484 ax_ext (expr
, addr_size_bits
);
3485 /* No need for a swap here. */
3486 ax_simple (expr
, aop_equal
);
3487 ax_simple (expr
, aop_log_not
);
3490 case DW_OP_call_frame_cfa
:
3493 CORE_ADDR text_offset
;
3495 const gdb_byte
*cfa_start
, *cfa_end
;
3497 if (dwarf2_fetch_cfa_info (arch
, expr
->scope
, per_cu
,
3499 &text_offset
, &cfa_start
, &cfa_end
))
3502 ax_reg (expr
, regnum
);
3505 ax_const_l (expr
, off
);
3506 ax_simple (expr
, aop_add
);
3511 /* Another expression. */
3512 ax_const_l (expr
, text_offset
);
3513 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3514 cfa_start
, cfa_end
, per_cu
);
3517 loc
->kind
= axs_lvalue_memory
;
3521 case DW_OP_GNU_push_tls_address
:
3522 case DW_OP_form_tls_address
:
3526 case DW_OP_push_object_address
:
3531 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3533 i
= ax_goto (expr
, aop_goto
);
3534 dw_labels
.push_back (op_ptr
+ offset
- base
);
3535 patches
.push_back (i
);
3539 offset
= extract_signed_integer (op_ptr
, 2, byte_order
);
3541 /* Zero extend the operand. */
3542 ax_zero_ext (expr
, addr_size_bits
);
3543 i
= ax_goto (expr
, aop_if_goto
);
3544 dw_labels
.push_back (op_ptr
+ offset
- base
);
3545 patches
.push_back (i
);
3552 case DW_OP_bit_piece
:
3554 uint64_t size
, offset
;
3556 if (op_ptr
- 1 == previous_piece
)
3557 error (_("Cannot translate empty pieces to agent expressions"));
3558 previous_piece
= op_ptr
- 1;
3560 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &size
);
3561 if (op
== DW_OP_piece
)
3567 op_ptr
= safe_read_uleb128 (op_ptr
, op_end
, &offset
);
3569 if (bits_collected
+ size
> 8 * sizeof (LONGEST
))
3570 error (_("Expression pieces exceed word size"));
3572 /* Access the bits. */
3575 case axs_lvalue_register
:
3576 ax_reg (expr
, loc
->u
.reg
);
3579 case axs_lvalue_memory
:
3580 /* Offset the pointer, if needed. */
3583 ax_const_l (expr
, offset
/ 8);
3584 ax_simple (expr
, aop_add
);
3587 access_memory (arch
, expr
, size
);
3591 /* For a bits-big-endian target, shift up what we already
3592 have. For a bits-little-endian target, shift up the
3593 new data. Note that there is a potential bug here if
3594 the DWARF expression leaves multiple values on the
3596 if (bits_collected
> 0)
3598 if (bits_big_endian
)
3600 ax_simple (expr
, aop_swap
);
3601 ax_const_l (expr
, size
);
3602 ax_simple (expr
, aop_lsh
);
3603 /* We don't need a second swap here, because
3604 aop_bit_or is symmetric. */
3608 ax_const_l (expr
, size
);
3609 ax_simple (expr
, aop_lsh
);
3611 ax_simple (expr
, aop_bit_or
);
3614 bits_collected
+= size
;
3615 loc
->kind
= axs_rvalue
;
3619 case DW_OP_GNU_uninit
:
3625 struct dwarf2_locexpr_baton block
;
3626 int size
= (op
== DW_OP_call2
? 2 : 4);
3629 uoffset
= extract_unsigned_integer (op_ptr
, size
, byte_order
);
3632 offset
.cu_off
= uoffset
;
3633 block
= dwarf2_fetch_die_loc_cu_off (offset
, per_cu
,
3636 /* DW_OP_call_ref is currently not supported. */
3637 gdb_assert (block
.per_cu
== per_cu
);
3639 dwarf2_compile_expr_to_ax (expr
, loc
, arch
, addr_size
,
3640 block
.data
, block
.data
+ block
.size
,
3645 case DW_OP_call_ref
:
3653 /* Patch all the branches we emitted. */
3654 for (i
= 0; i
< patches
.size (); ++i
)
3656 int targ
= offsets
[dw_labels
[i
]];
3658 internal_error (__FILE__
, __LINE__
, _("invalid label"));
3659 ax_label (expr
, patches
[i
], targ
);
3664 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
3665 evaluator to calculate the location. */
3666 static struct value
*
3667 locexpr_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
3669 struct dwarf2_locexpr_baton
*dlbaton
3670 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3673 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3674 dlbaton
->size
, dlbaton
->per_cu
);
3679 /* Return the value of SYMBOL in FRAME at (callee) FRAME's function
3680 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
3683 static struct value
*
3684 locexpr_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
3686 struct dwarf2_locexpr_baton
*dlbaton
3687 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3689 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, dlbaton
->data
,
3693 /* Implementation of get_symbol_read_needs from
3694 symbol_computed_ops. */
3696 static enum symbol_needs_kind
3697 locexpr_get_symbol_read_needs (struct symbol
*symbol
)
3699 struct dwarf2_locexpr_baton
*dlbaton
3700 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
3702 return dwarf2_loc_desc_get_symbol_read_needs (dlbaton
->data
, dlbaton
->size
,
3706 /* Return true if DATA points to the end of a piece. END is one past
3707 the last byte in the expression. */
3710 piece_end_p (const gdb_byte
*data
, const gdb_byte
*end
)
3712 return data
== end
|| data
[0] == DW_OP_piece
|| data
[0] == DW_OP_bit_piece
;
3715 /* Helper for locexpr_describe_location_piece that finds the name of a
3719 locexpr_regname (struct gdbarch
*gdbarch
, int dwarf_regnum
)
3723 /* This doesn't use dwarf_reg_to_regnum_or_error on purpose.
3724 We'd rather print *something* here than throw an error. */
3725 regnum
= dwarf_reg_to_regnum (gdbarch
, dwarf_regnum
);
3726 /* gdbarch_register_name may just return "", return something more
3727 descriptive for bad register numbers. */
3730 /* The text is output as "$bad_register_number".
3731 That is why we use the underscores. */
3732 return _("bad_register_number");
3734 return gdbarch_register_name (gdbarch
, regnum
);
3737 /* Nicely describe a single piece of a location, returning an updated
3738 position in the bytecode sequence. This function cannot recognize
3739 all locations; if a location is not recognized, it simply returns
3740 DATA. If there is an error during reading, e.g. we run off the end
3741 of the buffer, an error is thrown. */
3743 static const gdb_byte
*
3744 locexpr_describe_location_piece (struct symbol
*symbol
, struct ui_file
*stream
,
3745 CORE_ADDR addr
, struct objfile
*objfile
,
3746 struct dwarf2_per_cu_data
*per_cu
,
3747 const gdb_byte
*data
, const gdb_byte
*end
,
3748 unsigned int addr_size
)
3750 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
3753 if (data
[0] >= DW_OP_reg0
&& data
[0] <= DW_OP_reg31
)
3755 fprintf_filtered (stream
, _("a variable in $%s"),
3756 locexpr_regname (gdbarch
, data
[0] - DW_OP_reg0
));
3759 else if (data
[0] == DW_OP_regx
)
3763 data
= safe_read_uleb128 (data
+ 1, end
, ®
);
3764 fprintf_filtered (stream
, _("a variable in $%s"),
3765 locexpr_regname (gdbarch
, reg
));
3767 else if (data
[0] == DW_OP_fbreg
)
3769 const struct block
*b
;
3770 struct symbol
*framefunc
;
3772 int64_t frame_offset
;
3773 const gdb_byte
*base_data
, *new_data
, *save_data
= data
;
3775 int64_t base_offset
= 0;
3777 new_data
= safe_read_sleb128 (data
+ 1, end
, &frame_offset
);
3778 if (!piece_end_p (new_data
, end
))
3782 b
= block_for_pc (addr
);
3785 error (_("No block found for address for symbol \"%s\"."),
3786 SYMBOL_PRINT_NAME (symbol
));
3788 framefunc
= block_linkage_function (b
);
3791 error (_("No function found for block for symbol \"%s\"."),
3792 SYMBOL_PRINT_NAME (symbol
));
3794 func_get_frame_base_dwarf_block (framefunc
, addr
, &base_data
, &base_size
);
3796 if (base_data
[0] >= DW_OP_breg0
&& base_data
[0] <= DW_OP_breg31
)
3798 const gdb_byte
*buf_end
;
3800 frame_reg
= base_data
[0] - DW_OP_breg0
;
3801 buf_end
= safe_read_sleb128 (base_data
+ 1, base_data
+ base_size
,
3803 if (buf_end
!= base_data
+ base_size
)
3804 error (_("Unexpected opcode after "
3805 "DW_OP_breg%u for symbol \"%s\"."),
3806 frame_reg
, SYMBOL_PRINT_NAME (symbol
));
3808 else if (base_data
[0] >= DW_OP_reg0
&& base_data
[0] <= DW_OP_reg31
)
3810 /* The frame base is just the register, with no offset. */
3811 frame_reg
= base_data
[0] - DW_OP_reg0
;
3816 /* We don't know what to do with the frame base expression,
3817 so we can't trace this variable; give up. */
3821 fprintf_filtered (stream
,
3822 _("a variable at frame base reg $%s offset %s+%s"),
3823 locexpr_regname (gdbarch
, frame_reg
),
3824 plongest (base_offset
), plongest (frame_offset
));
3826 else if (data
[0] >= DW_OP_breg0
&& data
[0] <= DW_OP_breg31
3827 && piece_end_p (data
, end
))
3831 data
= safe_read_sleb128 (data
+ 1, end
, &offset
);
3833 fprintf_filtered (stream
,
3834 _("a variable at offset %s from base reg $%s"),
3836 locexpr_regname (gdbarch
, data
[0] - DW_OP_breg0
));
3839 /* The location expression for a TLS variable looks like this (on a
3842 DW_AT_location : 10 byte block: 3 4 0 0 0 0 0 0 0 e0
3843 (DW_OP_addr: 4; DW_OP_GNU_push_tls_address)
3845 0x3 is the encoding for DW_OP_addr, which has an operand as long
3846 as the size of an address on the target machine (here is 8
3847 bytes). Note that more recent version of GCC emit DW_OP_const4u
3848 or DW_OP_const8u, depending on address size, rather than
3849 DW_OP_addr. 0xe0 is the encoding for DW_OP_GNU_push_tls_address.
3850 The operand represents the offset at which the variable is within
3851 the thread local storage. */
3853 else if (data
+ 1 + addr_size
< end
3854 && (data
[0] == DW_OP_addr
3855 || (addr_size
== 4 && data
[0] == DW_OP_const4u
)
3856 || (addr_size
== 8 && data
[0] == DW_OP_const8u
))
3857 && (data
[1 + addr_size
] == DW_OP_GNU_push_tls_address
3858 || data
[1 + addr_size
] == DW_OP_form_tls_address
)
3859 && piece_end_p (data
+ 2 + addr_size
, end
))
3862 offset
= extract_unsigned_integer (data
+ 1, addr_size
,
3863 gdbarch_byte_order (gdbarch
));
3865 fprintf_filtered (stream
,
3866 _("a thread-local variable at offset 0x%s "
3867 "in the thread-local storage for `%s'"),
3868 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3870 data
+= 1 + addr_size
+ 1;
3873 /* With -gsplit-dwarf a TLS variable can also look like this:
3874 DW_AT_location : 3 byte block: fc 4 e0
3875 (DW_OP_GNU_const_index: 4;
3876 DW_OP_GNU_push_tls_address) */
3877 else if (data
+ 3 <= end
3878 && data
+ 1 + (leb128_size
= skip_leb128 (data
+ 1, end
)) < end
3879 && data
[0] == DW_OP_GNU_const_index
3881 && (data
[1 + leb128_size
] == DW_OP_GNU_push_tls_address
3882 || data
[1 + leb128_size
] == DW_OP_form_tls_address
)
3883 && piece_end_p (data
+ 2 + leb128_size
, end
))
3887 data
= safe_read_uleb128 (data
+ 1, end
, &offset
);
3888 offset
= dwarf2_read_addr_index (per_cu
, offset
);
3889 fprintf_filtered (stream
,
3890 _("a thread-local variable at offset 0x%s "
3891 "in the thread-local storage for `%s'"),
3892 phex_nz (offset
, addr_size
), objfile_name (objfile
));
3896 else if (data
[0] >= DW_OP_lit0
3897 && data
[0] <= DW_OP_lit31
3899 && data
[1] == DW_OP_stack_value
)
3901 fprintf_filtered (stream
, _("the constant %d"), data
[0] - DW_OP_lit0
);
3908 /* Disassemble an expression, stopping at the end of a piece or at the
3909 end of the expression. Returns a pointer to the next unread byte
3910 in the input expression. If ALL is nonzero, then this function
3911 will keep going until it reaches the end of the expression.
3912 If there is an error during reading, e.g. we run off the end
3913 of the buffer, an error is thrown. */
3915 static const gdb_byte
*
3916 disassemble_dwarf_expression (struct ui_file
*stream
,
3917 struct gdbarch
*arch
, unsigned int addr_size
,
3918 int offset_size
, const gdb_byte
*start
,
3919 const gdb_byte
*data
, const gdb_byte
*end
,
3920 int indent
, int all
,
3921 struct dwarf2_per_cu_data
*per_cu
)
3925 || (data
[0] != DW_OP_piece
&& data
[0] != DW_OP_bit_piece
)))
3927 enum dwarf_location_atom op
= (enum dwarf_location_atom
) *data
++;
3932 name
= get_DW_OP_name (op
);
3935 error (_("Unrecognized DWARF opcode 0x%02x at %ld"),
3936 op
, (long) (data
- 1 - start
));
3937 fprintf_filtered (stream
, " %*ld: %s", indent
+ 4,
3938 (long) (data
- 1 - start
), name
);
3943 ul
= extract_unsigned_integer (data
, addr_size
,
3944 gdbarch_byte_order (arch
));
3946 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
3950 ul
= extract_unsigned_integer (data
, 1, gdbarch_byte_order (arch
));
3952 fprintf_filtered (stream
, " %s", pulongest (ul
));
3955 l
= extract_signed_integer (data
, 1, gdbarch_byte_order (arch
));
3957 fprintf_filtered (stream
, " %s", plongest (l
));
3960 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
3962 fprintf_filtered (stream
, " %s", pulongest (ul
));
3965 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
3967 fprintf_filtered (stream
, " %s", plongest (l
));
3970 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
3972 fprintf_filtered (stream
, " %s", pulongest (ul
));
3975 l
= extract_signed_integer (data
, 4, gdbarch_byte_order (arch
));
3977 fprintf_filtered (stream
, " %s", plongest (l
));
3980 ul
= extract_unsigned_integer (data
, 8, gdbarch_byte_order (arch
));
3982 fprintf_filtered (stream
, " %s", pulongest (ul
));
3985 l
= extract_signed_integer (data
, 8, gdbarch_byte_order (arch
));
3987 fprintf_filtered (stream
, " %s", plongest (l
));
3990 data
= safe_read_uleb128 (data
, end
, &ul
);
3991 fprintf_filtered (stream
, " %s", pulongest (ul
));
3994 data
= safe_read_sleb128 (data
, end
, &l
);
3995 fprintf_filtered (stream
, " %s", plongest (l
));
4030 fprintf_filtered (stream
, " [$%s]",
4031 locexpr_regname (arch
, op
- DW_OP_reg0
));
4035 data
= safe_read_uleb128 (data
, end
, &ul
);
4036 fprintf_filtered (stream
, " %s [$%s]", pulongest (ul
),
4037 locexpr_regname (arch
, (int) ul
));
4040 case DW_OP_implicit_value
:
4041 data
= safe_read_uleb128 (data
, end
, &ul
);
4043 fprintf_filtered (stream
, " %s", pulongest (ul
));
4078 data
= safe_read_sleb128 (data
, end
, &l
);
4079 fprintf_filtered (stream
, " %s [$%s]", plongest (l
),
4080 locexpr_regname (arch
, op
- DW_OP_breg0
));
4084 data
= safe_read_uleb128 (data
, end
, &ul
);
4085 data
= safe_read_sleb128 (data
, end
, &l
);
4086 fprintf_filtered (stream
, " register %s [$%s] offset %s",
4088 locexpr_regname (arch
, (int) ul
),
4093 data
= safe_read_sleb128 (data
, end
, &l
);
4094 fprintf_filtered (stream
, " %s", plongest (l
));
4097 case DW_OP_xderef_size
:
4098 case DW_OP_deref_size
:
4100 fprintf_filtered (stream
, " %d", *data
);
4104 case DW_OP_plus_uconst
:
4105 data
= safe_read_uleb128 (data
, end
, &ul
);
4106 fprintf_filtered (stream
, " %s", pulongest (ul
));
4110 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4112 fprintf_filtered (stream
, " to %ld",
4113 (long) (data
+ l
- start
));
4117 l
= extract_signed_integer (data
, 2, gdbarch_byte_order (arch
));
4119 fprintf_filtered (stream
, " %ld",
4120 (long) (data
+ l
- start
));
4124 ul
= extract_unsigned_integer (data
, 2, gdbarch_byte_order (arch
));
4126 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 2));
4130 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4132 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4135 case DW_OP_call_ref
:
4136 ul
= extract_unsigned_integer (data
, offset_size
,
4137 gdbarch_byte_order (arch
));
4138 data
+= offset_size
;
4139 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, offset_size
));
4143 data
= safe_read_uleb128 (data
, end
, &ul
);
4144 fprintf_filtered (stream
, " %s (bytes)", pulongest (ul
));
4147 case DW_OP_bit_piece
:
4151 data
= safe_read_uleb128 (data
, end
, &ul
);
4152 data
= safe_read_uleb128 (data
, end
, &offset
);
4153 fprintf_filtered (stream
, " size %s offset %s (bits)",
4154 pulongest (ul
), pulongest (offset
));
4158 case DW_OP_GNU_implicit_pointer
:
4160 ul
= extract_unsigned_integer (data
, offset_size
,
4161 gdbarch_byte_order (arch
));
4162 data
+= offset_size
;
4164 data
= safe_read_sleb128 (data
, end
, &l
);
4166 fprintf_filtered (stream
, " DIE %s offset %s",
4167 phex_nz (ul
, offset_size
),
4172 case DW_OP_GNU_deref_type
:
4174 int addr_size
= *data
++;
4178 data
= safe_read_uleb128 (data
, end
, &ul
);
4180 type
= dwarf2_get_die_type (offset
, per_cu
);
4181 fprintf_filtered (stream
, "<");
4182 type_print (type
, "", stream
, -1);
4183 fprintf_filtered (stream
, " [0x%s]> %d", phex_nz (offset
.cu_off
, 0),
4188 case DW_OP_GNU_const_type
:
4193 data
= safe_read_uleb128 (data
, end
, &ul
);
4194 type_die
.cu_off
= ul
;
4195 type
= dwarf2_get_die_type (type_die
, per_cu
);
4196 fprintf_filtered (stream
, "<");
4197 type_print (type
, "", stream
, -1);
4198 fprintf_filtered (stream
, " [0x%s]>", phex_nz (type_die
.cu_off
, 0));
4202 case DW_OP_GNU_regval_type
:
4208 data
= safe_read_uleb128 (data
, end
, ®
);
4209 data
= safe_read_uleb128 (data
, end
, &ul
);
4210 type_die
.cu_off
= ul
;
4212 type
= dwarf2_get_die_type (type_die
, per_cu
);
4213 fprintf_filtered (stream
, "<");
4214 type_print (type
, "", stream
, -1);
4215 fprintf_filtered (stream
, " [0x%s]> [$%s]",
4216 phex_nz (type_die
.cu_off
, 0),
4217 locexpr_regname (arch
, reg
));
4221 case DW_OP_GNU_convert
:
4222 case DW_OP_GNU_reinterpret
:
4226 data
= safe_read_uleb128 (data
, end
, &ul
);
4227 type_die
.cu_off
= ul
;
4229 if (type_die
.cu_off
== 0)
4230 fprintf_filtered (stream
, "<0>");
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]>", phex_nz (type_die
.cu_off
, 0));
4243 case DW_OP_GNU_entry_value
:
4244 data
= safe_read_uleb128 (data
, end
, &ul
);
4245 fputc_filtered ('\n', stream
);
4246 disassemble_dwarf_expression (stream
, arch
, addr_size
, offset_size
,
4247 start
, data
, data
+ ul
, indent
+ 2,
4252 case DW_OP_GNU_parameter_ref
:
4253 ul
= extract_unsigned_integer (data
, 4, gdbarch_byte_order (arch
));
4255 fprintf_filtered (stream
, " offset %s", phex_nz (ul
, 4));
4258 case DW_OP_GNU_addr_index
:
4259 data
= safe_read_uleb128 (data
, end
, &ul
);
4260 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4261 fprintf_filtered (stream
, " 0x%s", phex_nz (ul
, addr_size
));
4263 case DW_OP_GNU_const_index
:
4264 data
= safe_read_uleb128 (data
, end
, &ul
);
4265 ul
= dwarf2_read_addr_index (per_cu
, ul
);
4266 fprintf_filtered (stream
, " %s", pulongest (ul
));
4270 fprintf_filtered (stream
, "\n");
4276 /* Describe a single location, which may in turn consist of multiple
4280 locexpr_describe_location_1 (struct symbol
*symbol
, CORE_ADDR addr
,
4281 struct ui_file
*stream
,
4282 const gdb_byte
*data
, size_t size
,
4283 struct objfile
*objfile
, unsigned int addr_size
,
4284 int offset_size
, struct dwarf2_per_cu_data
*per_cu
)
4286 const gdb_byte
*end
= data
+ size
;
4287 int first_piece
= 1, bad
= 0;
4291 const gdb_byte
*here
= data
;
4292 int disassemble
= 1;
4297 fprintf_filtered (stream
, _(", and "));
4299 if (!dwarf_always_disassemble
)
4301 data
= locexpr_describe_location_piece (symbol
, stream
,
4302 addr
, objfile
, per_cu
,
4303 data
, end
, addr_size
);
4304 /* If we printed anything, or if we have an empty piece,
4305 then don't disassemble. */
4307 || data
[0] == DW_OP_piece
4308 || data
[0] == DW_OP_bit_piece
)
4313 fprintf_filtered (stream
, _("a complex DWARF expression:\n"));
4314 data
= disassemble_dwarf_expression (stream
,
4315 get_objfile_arch (objfile
),
4316 addr_size
, offset_size
, data
,
4318 dwarf_always_disassemble
,
4324 int empty
= data
== here
;
4327 fprintf_filtered (stream
, " ");
4328 if (data
[0] == DW_OP_piece
)
4332 data
= safe_read_uleb128 (data
+ 1, end
, &bytes
);
4335 fprintf_filtered (stream
, _("an empty %s-byte piece"),
4338 fprintf_filtered (stream
, _(" [%s-byte piece]"),
4341 else if (data
[0] == DW_OP_bit_piece
)
4343 uint64_t bits
, offset
;
4345 data
= safe_read_uleb128 (data
+ 1, end
, &bits
);
4346 data
= safe_read_uleb128 (data
, end
, &offset
);
4349 fprintf_filtered (stream
,
4350 _("an empty %s-bit piece"),
4353 fprintf_filtered (stream
,
4354 _(" [%s-bit piece, offset %s bits]"),
4355 pulongest (bits
), pulongest (offset
));
4365 if (bad
|| data
> end
)
4366 error (_("Corrupted DWARF2 expression for \"%s\"."),
4367 SYMBOL_PRINT_NAME (symbol
));
4370 /* Print a natural-language description of SYMBOL to STREAM. This
4371 version is for a symbol with a single location. */
4374 locexpr_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4375 struct ui_file
*stream
)
4377 struct dwarf2_locexpr_baton
*dlbaton
4378 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4379 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4380 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4381 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4383 locexpr_describe_location_1 (symbol
, addr
, stream
,
4384 dlbaton
->data
, dlbaton
->size
,
4385 objfile
, addr_size
, offset_size
,
4389 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4390 any necessary bytecode in AX. */
4393 locexpr_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4394 struct agent_expr
*ax
, struct axs_value
*value
)
4396 struct dwarf2_locexpr_baton
*dlbaton
4397 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4398 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4400 if (dlbaton
->size
== 0)
4401 value
->optimized_out
= 1;
4403 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
,
4404 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4408 /* symbol_computed_ops 'generate_c_location' method. */
4411 locexpr_generate_c_location (struct symbol
*sym
, struct ui_file
*stream
,
4412 struct gdbarch
*gdbarch
,
4413 unsigned char *registers_used
,
4414 CORE_ADDR pc
, const char *result_name
)
4416 struct dwarf2_locexpr_baton
*dlbaton
4417 = (struct dwarf2_locexpr_baton
*) SYMBOL_LOCATION_BATON (sym
);
4418 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4420 if (dlbaton
->size
== 0)
4421 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4423 compile_dwarf_expr_to_c (stream
, result_name
,
4424 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4425 dlbaton
->data
, dlbaton
->data
+ dlbaton
->size
,
4429 /* The set of location functions used with the DWARF-2 expression
4431 const struct symbol_computed_ops dwarf2_locexpr_funcs
= {
4432 locexpr_read_variable
,
4433 locexpr_read_variable_at_entry
,
4434 locexpr_get_symbol_read_needs
,
4435 locexpr_describe_location
,
4436 0, /* location_has_loclist */
4437 locexpr_tracepoint_var_ref
,
4438 locexpr_generate_c_location
4442 /* Wrapper functions for location lists. These generally find
4443 the appropriate location expression and call something above. */
4445 /* Return the value of SYMBOL in FRAME using the DWARF-2 expression
4446 evaluator to calculate the location. */
4447 static struct value
*
4448 loclist_read_variable (struct symbol
*symbol
, struct frame_info
*frame
)
4450 struct dwarf2_loclist_baton
*dlbaton
4451 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4453 const gdb_byte
*data
;
4455 CORE_ADDR pc
= frame
? get_frame_address_in_block (frame
) : 0;
4457 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4458 val
= dwarf2_evaluate_loc_desc (SYMBOL_TYPE (symbol
), frame
, data
, size
,
4464 /* Read variable SYMBOL like loclist_read_variable at (callee) FRAME's function
4465 entry. SYMBOL should be a function parameter, otherwise NO_ENTRY_VALUE_ERROR
4468 Function always returns non-NULL value, it may be marked optimized out if
4469 inferior frame information is not available. It throws NO_ENTRY_VALUE_ERROR
4470 if it cannot resolve the parameter for any reason. */
4472 static struct value
*
4473 loclist_read_variable_at_entry (struct symbol
*symbol
, struct frame_info
*frame
)
4475 struct dwarf2_loclist_baton
*dlbaton
4476 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4477 const gdb_byte
*data
;
4481 if (frame
== NULL
|| !get_frame_func_if_available (frame
, &pc
))
4482 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4484 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4486 return allocate_optimized_out_value (SYMBOL_TYPE (symbol
));
4488 return value_of_dwarf_block_entry (SYMBOL_TYPE (symbol
), frame
, data
, size
);
4491 /* Implementation of get_symbol_read_needs from
4492 symbol_computed_ops. */
4494 static enum symbol_needs_kind
4495 loclist_symbol_needs (struct symbol
*symbol
)
4497 /* If there's a location list, then assume we need to have a frame
4498 to choose the appropriate location expression. With tracking of
4499 global variables this is not necessarily true, but such tracking
4500 is disabled in GCC at the moment until we figure out how to
4503 return SYMBOL_NEEDS_FRAME
;
4506 /* Print a natural-language description of SYMBOL to STREAM. This
4507 version applies when there is a list of different locations, each
4508 with a specified address range. */
4511 loclist_describe_location (struct symbol
*symbol
, CORE_ADDR addr
,
4512 struct ui_file
*stream
)
4514 struct dwarf2_loclist_baton
*dlbaton
4515 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4516 const gdb_byte
*loc_ptr
, *buf_end
;
4517 struct objfile
*objfile
= dwarf2_per_cu_objfile (dlbaton
->per_cu
);
4518 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
4519 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
4520 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4521 int offset_size
= dwarf2_per_cu_offset_size (dlbaton
->per_cu
);
4522 int signed_addr_p
= bfd_get_sign_extend_vma (objfile
->obfd
);
4523 /* Adjust base_address for relocatable objects. */
4524 CORE_ADDR base_offset
= dwarf2_per_cu_text_offset (dlbaton
->per_cu
);
4525 CORE_ADDR base_address
= dlbaton
->base_address
+ base_offset
;
4528 loc_ptr
= dlbaton
->data
;
4529 buf_end
= dlbaton
->data
+ dlbaton
->size
;
4531 fprintf_filtered (stream
, _("multi-location:\n"));
4533 /* Iterate through locations until we run out. */
4536 CORE_ADDR low
= 0, high
= 0; /* init for gcc -Wall */
4538 enum debug_loc_kind kind
;
4539 const gdb_byte
*new_ptr
= NULL
; /* init for gcc -Wall */
4541 if (dlbaton
->from_dwo
)
4542 kind
= decode_debug_loc_dwo_addresses (dlbaton
->per_cu
,
4543 loc_ptr
, buf_end
, &new_ptr
,
4544 &low
, &high
, byte_order
);
4546 kind
= decode_debug_loc_addresses (loc_ptr
, buf_end
, &new_ptr
,
4548 byte_order
, addr_size
,
4553 case DEBUG_LOC_END_OF_LIST
:
4556 case DEBUG_LOC_BASE_ADDRESS
:
4557 base_address
= high
+ base_offset
;
4558 fprintf_filtered (stream
, _(" Base address %s"),
4559 paddress (gdbarch
, base_address
));
4561 case DEBUG_LOC_START_END
:
4562 case DEBUG_LOC_START_LENGTH
:
4564 case DEBUG_LOC_BUFFER_OVERFLOW
:
4565 case DEBUG_LOC_INVALID_ENTRY
:
4566 error (_("Corrupted DWARF expression for symbol \"%s\"."),
4567 SYMBOL_PRINT_NAME (symbol
));
4569 gdb_assert_not_reached ("bad debug_loc_kind");
4572 /* Otherwise, a location expression entry. */
4573 low
+= base_address
;
4574 high
+= base_address
;
4576 low
= gdbarch_adjust_dwarf2_addr (gdbarch
, low
);
4577 high
= gdbarch_adjust_dwarf2_addr (gdbarch
, high
);
4579 length
= extract_unsigned_integer (loc_ptr
, 2, byte_order
);
4582 /* (It would improve readability to print only the minimum
4583 necessary digits of the second number of the range.) */
4584 fprintf_filtered (stream
, _(" Range %s-%s: "),
4585 paddress (gdbarch
, low
), paddress (gdbarch
, high
));
4587 /* Now describe this particular location. */
4588 locexpr_describe_location_1 (symbol
, low
, stream
, loc_ptr
, length
,
4589 objfile
, addr_size
, offset_size
,
4592 fprintf_filtered (stream
, "\n");
4598 /* Describe the location of SYMBOL as an agent value in VALUE, generating
4599 any necessary bytecode in AX. */
4601 loclist_tracepoint_var_ref (struct symbol
*symbol
, struct gdbarch
*gdbarch
,
4602 struct agent_expr
*ax
, struct axs_value
*value
)
4604 struct dwarf2_loclist_baton
*dlbaton
4605 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (symbol
);
4606 const gdb_byte
*data
;
4608 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4610 data
= dwarf2_find_location_expression (dlbaton
, &size
, ax
->scope
);
4612 value
->optimized_out
= 1;
4614 dwarf2_compile_expr_to_ax (ax
, value
, gdbarch
, addr_size
, data
, data
+ size
,
4618 /* symbol_computed_ops 'generate_c_location' method. */
4621 loclist_generate_c_location (struct symbol
*sym
, struct ui_file
*stream
,
4622 struct gdbarch
*gdbarch
,
4623 unsigned char *registers_used
,
4624 CORE_ADDR pc
, const char *result_name
)
4626 struct dwarf2_loclist_baton
*dlbaton
4627 = (struct dwarf2_loclist_baton
*) SYMBOL_LOCATION_BATON (sym
);
4628 unsigned int addr_size
= dwarf2_per_cu_addr_size (dlbaton
->per_cu
);
4629 const gdb_byte
*data
;
4632 data
= dwarf2_find_location_expression (dlbaton
, &size
, pc
);
4634 error (_("symbol \"%s\" is optimized out"), SYMBOL_NATURAL_NAME (sym
));
4636 compile_dwarf_expr_to_c (stream
, result_name
,
4637 sym
, pc
, gdbarch
, registers_used
, addr_size
,
4642 /* The set of location functions used with the DWARF-2 expression
4643 evaluator and location lists. */
4644 const struct symbol_computed_ops dwarf2_loclist_funcs
= {
4645 loclist_read_variable
,
4646 loclist_read_variable_at_entry
,
4647 loclist_symbol_needs
,
4648 loclist_describe_location
,
4649 1, /* location_has_loclist */
4650 loclist_tracepoint_var_ref
,
4651 loclist_generate_c_location
4654 /* Provide a prototype to silence -Wmissing-prototypes. */
4655 extern initialize_file_ftype _initialize_dwarf2loc
;
4658 _initialize_dwarf2loc (void)
4660 add_setshow_zuinteger_cmd ("entry-values", class_maintenance
,
4661 &entry_values_debug
,
4662 _("Set entry values and tail call frames "
4664 _("Show entry values and tail call frames "
4666 _("When non-zero, the process of determining "
4667 "parameter values from function entry point "
4668 "and tail call frames will be printed."),
4670 show_entry_values_debug
,
4671 &setdebuglist
, &showdebuglist
);
4674 register_self_test (selftests::copy_bitwise_tests
);