1 /* Copyright (c) 2008-2014. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
10 #define DW_LANG_Objc DW_LANG_ObjC /* fix spelling error in older dwarf.h */
12 #include <elfutils/libdw.h>
14 #include <simgrid_config.h>
16 #include <xbt/sysdep.h>
18 #include "mc_object_info.h"
19 #include "mc_private.h"
23 static void MC_dwarf_register_global_variable(mc_object_info_t info, dw_variable_t variable);
24 static void MC_register_variable(mc_object_info_t info, dw_frame_t frame, dw_variable_t variable);
25 static void MC_dwarf_register_non_global_variable(mc_object_info_t info, dw_frame_t frame, dw_variable_t variable);
26 static void MC_dwarf_register_variable(mc_object_info_t info, dw_frame_t frame, dw_variable_t variable);
28 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dwarf, mc, "DWARF processing");
30 /** \brief The default DW_TAG_lower_bound for a given DW_AT_language.
32 * The default for a given language is defined in the DWARF spec.
34 * \param language consant as defined by the DWARf spec
36 static uint64_t MC_dwarf_default_lower_bound(int lang);
38 /** \brief Computes the the element_count of a DW_TAG_enumeration_type DIE
40 * This is the number of elements in a given array dimension.
42 * A reference of the compilation unit (DW_TAG_compile_unit) is
43 * needed because the default lower bound (when there is no DW_AT_lower_bound)
44 * depends of the language of the compilation unit (DW_AT_language).
46 * \param die DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type
47 * \param unit DIE of the DW_TAG_compile_unit
49 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die * die,
52 /** \brief Computes the number of elements of a given DW_TAG_array_type.
54 * \param die DIE for the DW_TAG_array_type
56 static uint64_t MC_dwarf_array_element_count(Dwarf_Die * die, Dwarf_Die * unit);
58 /** \brief Process a DIE
60 * \param info the resulting object fot the library/binary file (output)
61 * \param die the current DIE
62 * \param unit the DIE of the compile unit of the current DIE
63 * \param frame containg frame if any
65 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die * die,
66 Dwarf_Die * unit, dw_frame_t frame,
69 /** \brief Process a type DIE
71 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die * die,
72 Dwarf_Die * unit, dw_frame_t frame,
75 /** \brief Calls MC_dwarf_handle_die on all childrend of the given die
77 * \param info the resulting object fot the library/binary file (output)
78 * \param die the current DIE
79 * \param unit the DIE of the compile unit of the current DIE
80 * \param frame containg frame if any
82 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die * die,
83 Dwarf_Die * unit, dw_frame_t frame,
86 /** \brief Handle a variable (DW_TAG_variable or other)
88 * \param info the resulting object fot the library/binary file (output)
89 * \param die the current DIE
90 * \param unit the DIE of the compile unit of the current DIE
91 * \param frame containg frame if any
93 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die * die,
94 Dwarf_Die * unit, dw_frame_t frame,
97 /** \brief Get the DW_TAG_type of the DIE
100 * \return DW_TAG_type attribute as a new string (NULL if none)
102 static char *MC_dwarf_at_type(Dwarf_Die * die);
104 /** \brief Get the name of an attribute (DW_AT_*) from its code
106 * \param attr attribute code (see the DWARF specification)
107 * \return name of the attribute
109 const char *MC_dwarf_attrname(int attr)
112 #include "mc_dwarf_attrnames.h"
114 return "DW_AT_unknown";
118 /** \brief Get the name of a dwarf tag (DW_TAG_*) from its code
120 * \param tag tag code (see the DWARF specification)
121 * \return name of the tag
123 const char *MC_dwarf_tagname(int tag)
126 #include "mc_dwarf_tagnames.h"
128 return "DW_TAG_invalid";
130 return "DW_TAG_unknown";
134 /** \brief A class of DWARF tags (DW_TAG_*)
136 typedef enum mc_tag_class {
145 static mc_tag_class MC_dwarf_tag_classify(int tag)
149 case DW_TAG_array_type:
150 case DW_TAG_class_type:
151 case DW_TAG_enumeration_type:
153 case DW_TAG_pointer_type:
154 case DW_TAG_reference_type:
155 case DW_TAG_rvalue_reference_type:
156 case DW_TAG_string_type:
157 case DW_TAG_structure_type:
158 case DW_TAG_subroutine_type:
159 case DW_TAG_union_type:
160 case DW_TAG_ptr_to_member_type:
161 case DW_TAG_set_type:
162 case DW_TAG_subrange_type:
163 case DW_TAG_base_type:
164 case DW_TAG_const_type:
165 case DW_TAG_file_type:
166 case DW_TAG_packed_type:
167 case DW_TAG_volatile_type:
168 case DW_TAG_restrict_type:
169 case DW_TAG_interface_type:
170 case DW_TAG_unspecified_type:
171 case DW_TAG_shared_type:
174 case DW_TAG_subprogram:
175 return mc_tag_subprogram;
177 case DW_TAG_variable:
178 case DW_TAG_formal_parameter:
179 return mc_tag_variable;
181 case DW_TAG_lexical_block:
182 case DW_TAG_try_block:
183 case DW_TAG_catch_block:
184 case DW_TAG_inlined_subroutine:
185 case DW_TAG_with_stmt:
188 case DW_TAG_namespace:
189 return mc_tag_namespace;
192 return mc_tag_unknown;
197 #define MC_DW_CLASS_UNKNOWN 0
198 #define MC_DW_CLASS_ADDRESS 1 // Location in the address space of the program
199 #define MC_DW_CLASS_BLOCK 2 // Arbitrary block of bytes
200 #define MC_DW_CLASS_CONSTANT 3
201 #define MC_DW_CLASS_STRING 3 // String
202 #define MC_DW_CLASS_FLAG 4 // Boolean
203 #define MC_DW_CLASS_REFERENCE 5 // Reference to another DIE
204 #define MC_DW_CLASS_EXPRLOC 6 // DWARF expression/location description
205 #define MC_DW_CLASS_LINEPTR 7
206 #define MC_DW_CLASS_LOCLISTPTR 8
207 #define MC_DW_CLASS_MACPTR 9
208 #define MC_DW_CLASS_RANGELISTPTR 10
210 /** \brief Find the DWARF data class for a given DWARF data form
212 * This mapping is defined in the DWARF spec.
214 * \param form The form (values taken from the DWARF spec)
215 * \return An internal representation for the corresponding class
217 static int MC_dwarf_form_get_class(int form)
221 return MC_DW_CLASS_ADDRESS;
226 return MC_DW_CLASS_BLOCK;
233 return MC_DW_CLASS_CONSTANT;
236 return MC_DW_CLASS_STRING;
237 case DW_FORM_ref_addr:
242 case DW_FORM_ref_udata:
243 return MC_DW_CLASS_REFERENCE;
245 case DW_FORM_flag_present:
246 return MC_DW_CLASS_FLAG;
247 case DW_FORM_exprloc:
248 return MC_DW_CLASS_EXPRLOC;
252 return MC_DW_CLASS_UNKNOWN;
256 /** \brief Get the name of the tag of a given DIE
259 * \return name of the tag of this DIE
261 static inline const char *MC_dwarf_die_tagname(Dwarf_Die * die)
263 return MC_dwarf_tagname(dwarf_tag(die));
268 /** \brief Get an attribute of a given DIE as a string
271 * \param attribute attribute
272 * \return value of the given attribute of the given DIE
274 static const char *MC_dwarf_attr_integrate_string(Dwarf_Die * die,
277 Dwarf_Attribute attr;
278 if (!dwarf_attr_integrate(die, attribute, &attr)) {
281 return dwarf_formstring(&attr);
285 /** \brief Get the linkage name of a DIE.
287 * Use either DW_AT_linkage_name or DW_AT_MIPS_linkage_name.
288 * DW_AT_linkage_name is standardized since DWARF 4.
289 * Before this version of DWARF, the MIPS extensions
290 * DW_AT_MIPS_linkage_name is used (at least by GCC).
293 * \return linkage name of the given DIE (or NULL)
295 static const char *MC_dwarf_at_linkage_name(Dwarf_Die * die)
297 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_linkage_name);
299 name = MC_dwarf_attr_integrate_string(die, DW_AT_MIPS_linkage_name);
303 static Dwarf_Off MC_dwarf_attr_dieoffset(Dwarf_Die * die, int attribute)
305 Dwarf_Attribute attr;
306 if (dwarf_hasattr_integrate(die, attribute)) {
307 dwarf_attr_integrate(die, attribute, &attr);
308 Dwarf_Die subtype_die;
309 if (dwarf_formref_die(&attr, &subtype_die) == NULL) {
310 xbt_die("Could not find DIE");
312 return dwarf_dieoffset(&subtype_die);
317 static Dwarf_Off MC_dwarf_attr_integrate_dieoffset(Dwarf_Die * die,
320 Dwarf_Attribute attr;
321 if (dwarf_hasattr_integrate(die, attribute)) {
322 dwarf_attr_integrate(die, DW_AT_type, &attr);
323 Dwarf_Die subtype_die;
324 if (dwarf_formref_die(&attr, &subtype_die) == NULL) {
325 xbt_die("Could not find DIE");
327 return dwarf_dieoffset(&subtype_die);
332 /** \brief Find the type/subtype (DW_AT_type) for a DIE
335 * \return DW_AT_type reference as a global offset in hexadecimal (or NULL)
337 static char *MC_dwarf_at_type(Dwarf_Die * die)
339 Dwarf_Off offset = MC_dwarf_attr_integrate_dieoffset(die, DW_AT_type);
340 return offset == 0 ? NULL : bprintf("%" PRIx64, offset);
343 static uint64_t MC_dwarf_attr_integrate_addr(Dwarf_Die * die, int attribute)
345 Dwarf_Attribute attr;
346 if (dwarf_attr_integrate(die, attribute, &attr) == NULL)
349 if (dwarf_formaddr(&attr, &value) == 0)
350 return (uint64_t) value;
355 static uint64_t MC_dwarf_attr_integrate_uint(Dwarf_Die * die, int attribute,
356 uint64_t default_value)
358 Dwarf_Attribute attr;
359 if (dwarf_attr_integrate(die, attribute, &attr) == NULL)
360 return default_value;
362 return dwarf_formudata(dwarf_attr_integrate(die, attribute, &attr),
363 &value) == 0 ? (uint64_t) value : default_value;
366 static bool MC_dwarf_attr_flag(Dwarf_Die * die, int attribute, bool integrate)
368 Dwarf_Attribute attr;
369 if ((integrate ? dwarf_attr_integrate(die, attribute, &attr)
370 : dwarf_attr(die, attribute, &attr)) == 0)
374 if (dwarf_formflag(&attr, &result))
375 xbt_die("Unexpected form for attribute %s", MC_dwarf_attrname(attribute));
379 /** \brief Find the default lower bound for a given language
381 * The default lower bound of an array (when DW_TAG_lower_bound
382 * is missing) depends on the language of the compilation unit.
384 * \param lang Language of the compilation unit (values defined in the DWARF spec)
385 * \return Default lower bound of an array in this compilation unit
387 static uint64_t MC_dwarf_default_lower_bound(int lang)
393 case DW_LANG_C_plus_plus:
397 case DW_LANG_ObjC_plus_plus:
403 case DW_LANG_Fortran77:
404 case DW_LANG_Fortran90:
405 case DW_LANG_Fortran95:
406 case DW_LANG_Modula2:
407 case DW_LANG_Pascal83:
409 case DW_LANG_Cobol74:
410 case DW_LANG_Cobol85:
413 xbt_die("No default DW_TAG_lower_bound for language %i and none given",
419 /** \brief Finds the number of elements in a DW_TAG_subrange_type or DW_TAG_enumeration_type DIE
422 * \param unit DIE of the compilation unit
423 * \return number of elements in the range
425 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die * die,
428 xbt_assert(dwarf_tag(die) == DW_TAG_enumeration_type
429 || dwarf_tag(die) == DW_TAG_subrange_type,
430 "MC_dwarf_subrange_element_count called with DIE of type %s",
431 MC_dwarf_die_tagname(die));
433 // Use DW_TAG_count if present:
434 if (dwarf_hasattr_integrate(die, DW_AT_count)) {
435 return MC_dwarf_attr_integrate_uint(die, DW_AT_count, 0);
437 // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound + 1:
439 if (!dwarf_hasattr_integrate(die, DW_AT_upper_bound)) {
440 // This is not really 0, but the code expects this (we do not know):
443 uint64_t upper_bound =
444 MC_dwarf_attr_integrate_uint(die, DW_AT_upper_bound, -1);
446 uint64_t lower_bound = 0;
447 if (dwarf_hasattr_integrate(die, DW_AT_lower_bound)) {
448 lower_bound = MC_dwarf_attr_integrate_uint(die, DW_AT_lower_bound, -1);
450 lower_bound = MC_dwarf_default_lower_bound(dwarf_srclang(unit));
452 return upper_bound - lower_bound + 1;
455 /** \brief Finds the number of elements in a array type (DW_TAG_array_type)
457 * The compilation unit might be needed because the default lower
458 * bound depends on the language of the compilation unit.
460 * \param die the DIE of the DW_TAG_array_type
461 * \param unit the DIE of the compilation unit
462 * \return number of elements in this array type
464 static uint64_t MC_dwarf_array_element_count(Dwarf_Die * die, Dwarf_Die * unit)
466 xbt_assert(dwarf_tag(die) == DW_TAG_array_type,
467 "MC_dwarf_array_element_count called with DIE of type %s",
468 MC_dwarf_die_tagname(die));
473 for (res = dwarf_child(die, &child); res == 0;
474 res = dwarf_siblingof(&child, &child)) {
475 int child_tag = dwarf_tag(&child);
476 if (child_tag == DW_TAG_subrange_type
477 || child_tag == DW_TAG_enumeration_type) {
478 result *= MC_dwarf_subrange_element_count(&child, unit);
486 /** \brief Initialize the location of a member of a type
487 * (DW_AT_data_member_location of a DW_TAG_member).
489 * \param type a type (struct, class)
490 * \param member the member of the type
491 * \param child DIE of the member (DW_TAG_member)
493 static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member,
496 if (dwarf_hasattr(child, DW_AT_data_bit_offset)) {
497 xbt_die("Can't groke DW_AT_data_bit_offset.");
500 if (!dwarf_hasattr_integrate(child, DW_AT_data_member_location)) {
501 if (type->type != DW_TAG_union_type) {
503 ("Missing DW_AT_data_member_location field in DW_TAG_member %s of type <%"
504 PRIx64 ">%s", member->name, (uint64_t) type->id, type->name);
510 Dwarf_Attribute attr;
511 dwarf_attr_integrate(child, DW_AT_data_member_location, &attr);
512 int form = dwarf_whatform(&attr);
513 int klass = MC_dwarf_form_get_class(form);
515 case MC_DW_CLASS_EXPRLOC:
516 case MC_DW_CLASS_BLOCK:
517 // Location expression:
521 if (dwarf_getlocation(&attr, &expr, &len)) {
523 ("Could not read location expression DW_AT_data_member_location in DW_TAG_member %s of type <%"
524 PRIx64 ">%s", MC_dwarf_attr_integrate_string(child, DW_AT_name),
525 (uint64_t) type->id, type->name);
527 if (len == 1 && expr[0].atom == DW_OP_plus_uconst) {
528 member->offset = expr[0].number;
530 mc_dwarf_expression_init(&member->location, len, expr);
534 case MC_DW_CLASS_CONSTANT:
535 // Offset from the base address of the object:
538 if (!dwarf_formudata(&attr, &offset))
539 member->offset = offset;
541 xbt_die("Cannot get %s location <%" PRIx64 ">%s",
542 MC_dwarf_attr_integrate_string(child, DW_AT_name),
543 (uint64_t) type->id, type->name);
546 case MC_DW_CLASS_LOCLISTPTR:
547 // Reference to a location list:
549 case MC_DW_CLASS_REFERENCE:
550 // It's supposed to be possible in DWARF2 but I couldn't find its semantic
553 xbt_die("Can't handle form class (%i) / form 0x%x as DW_AT_member_location",
559 static void dw_type_free_voidp(void *t)
561 dw_type_free((dw_type_t) * (void **) t);
564 /** \brief Populate the list of members of a type
566 * \param info ELF object containing the type DIE
567 * \param die DIE of the type
568 * \param unit DIE of the compilation unit containing the type DIE
569 * \param type the type
571 static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die * die,
572 Dwarf_Die * unit, dw_type_t type)
576 xbt_assert(!type->members);
578 xbt_dynar_new(sizeof(dw_type_t), (void (*)(void *)) dw_type_free_voidp);
579 for (res = dwarf_child(die, &child); res == 0;
580 res = dwarf_siblingof(&child, &child)) {
581 int tag = dwarf_tag(&child);
582 if (tag == DW_TAG_member || tag == DW_TAG_inheritance) {
584 // Skip declarations:
585 if (MC_dwarf_attr_flag(&child, DW_AT_declaration, false))
588 // Skip compile time constants:
589 if (dwarf_hasattr(&child, DW_AT_const_value))
592 // TODO, we should use another type (because is is not a type but a member)
593 dw_type_t member = xbt_new0(s_dw_type_t, 1);
597 member->id = dwarf_dieoffset(&child);
599 const char *name = MC_dwarf_attr_integrate_string(&child, DW_AT_name);
601 member->name = xbt_strdup(name);
606 MC_dwarf_attr_integrate_uint(&child, DW_AT_byte_size, 0);
607 member->element_count = -1;
608 member->dw_type_id = MC_dwarf_at_type(&child);
609 member->members = NULL;
610 member->is_pointer_type = 0;
613 if (dwarf_hasattr(&child, DW_AT_data_bit_offset)) {
614 xbt_die("Can't groke DW_AT_data_bit_offset.");
617 MC_dwarf_fill_member_location(type, member, &child);
619 if (!member->dw_type_id) {
620 xbt_die("Missing type for member %s of <%" PRIx64 ">%s", member->name,
621 (uint64_t) type->id, type->name);
624 xbt_dynar_push(type->members, &member);
629 /** \brief Create a MC type object from a DIE
631 * \param info current object info object
632 * \param DIE (for a given type);
633 * \param unit compilation unit of the current DIE
634 * \return MC representation of the type
636 static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die * die,
637 Dwarf_Die * unit, dw_frame_t frame,
641 dw_type_t type = xbt_new0(s_dw_type_t, 1);
646 type->element_count = -1;
647 type->dw_type_id = NULL;
648 type->members = NULL;
649 type->is_pointer_type = 0;
652 type->type = dwarf_tag(die);
655 type->id = dwarf_dieoffset(die);
657 const char *prefix = "";
658 switch (type->type) {
659 case DW_TAG_structure_type:
662 case DW_TAG_union_type:
665 case DW_TAG_class_type:
672 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
675 ns ? bprintf("%s%s::%s", prefix, ns,
676 name) : bprintf("%s%s", prefix, name);
679 type->dw_type_id = MC_dwarf_at_type(die);
681 // Computation of the byte_size;
682 if (dwarf_hasattr_integrate(die, DW_AT_byte_size))
683 type->byte_size = MC_dwarf_attr_integrate_uint(die, DW_AT_byte_size, 0);
684 else if (type->type == DW_TAG_array_type
685 || type->type == DW_TAG_structure_type
686 || type->type == DW_TAG_class_type) {
688 if (dwarf_aggregate_size(die, &size) == 0) {
689 type->byte_size = size;
693 switch (type->type) {
694 case DW_TAG_array_type:
695 type->element_count = MC_dwarf_array_element_count(die, unit);
696 // TODO, handle DW_byte_stride and (not) DW_bit_stride
699 case DW_TAG_pointer_type:
700 case DW_TAG_reference_type:
701 case DW_TAG_rvalue_reference_type:
702 type->is_pointer_type = 1;
705 case DW_TAG_structure_type:
706 case DW_TAG_union_type:
707 case DW_TAG_class_type:
708 MC_dwarf_add_members(info, die, unit, type);
709 char *new_ns = ns == NULL ? xbt_strdup(type->name)
710 : bprintf("%s::%s", ns, name);
711 MC_dwarf_handle_children(info, die, unit, frame, new_ns);
719 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die * die,
720 Dwarf_Die * unit, dw_frame_t frame,
723 dw_type_t type = MC_dwarf_die_to_type(info, die, unit, frame, ns);
725 char *key = bprintf("%" PRIx64, (uint64_t) type->id);
726 xbt_dict_set(info->types, key, type, NULL);
729 if (type->name && type->byte_size != 0) {
730 xbt_dict_set(info->full_types_by_name, type->name, type, NULL);
734 static int mc_anonymous_variable_index = 0;
736 static dw_variable_t MC_die_to_variable(mc_object_info_t info, Dwarf_Die * die,
737 Dwarf_Die * unit, dw_frame_t frame,
740 // Skip declarations:
741 if (MC_dwarf_attr_flag(die, DW_AT_declaration, false))
744 // Skip compile time constants:
745 if (dwarf_hasattr(die, DW_AT_const_value))
748 Dwarf_Attribute attr_location;
749 if (dwarf_attr(die, DW_AT_location, &attr_location) == NULL) {
750 // No location: do not add it ?
754 dw_variable_t variable = xbt_new0(s_dw_variable_t, 1);
755 variable->dwarf_offset = dwarf_dieoffset(die);
756 variable->global = frame == NULL; // Can be override base on DW_AT_location
757 variable->object_info = info;
759 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
760 variable->name = xbt_strdup(name);
762 variable->type_origin = MC_dwarf_at_type(die);
764 int form = dwarf_whatform(&attr_location);
767 DW_FORM_sec_offset ? MC_DW_CLASS_CONSTANT : MC_dwarf_form_get_class(form);
769 case MC_DW_CLASS_EXPRLOC:
770 case MC_DW_CLASS_BLOCK:
771 // Location expression:
775 if (dwarf_getlocation(&attr_location, &expr, &len)) {
777 ("Could not read location expression in DW_AT_location of variable <%"
778 PRIx64 ">%s", (uint64_t) variable->dwarf_offset, variable->name);
781 if (len == 1 && expr[0].atom == DW_OP_addr) {
782 variable->global = 1;
783 uintptr_t offset = (uintptr_t) expr[0].number;
784 uintptr_t base = (uintptr_t) MC_object_base_address(info);
785 variable->address = (void *) (base + offset);
787 mc_dwarf_location_list_init_from_expression(&variable->locations, len,
793 case MC_DW_CLASS_LOCLISTPTR:
794 case MC_DW_CLASS_CONSTANT:
795 // Reference to location list:
796 mc_dwarf_location_list_init(&variable->locations, info, die,
800 xbt_die("Unexpected form 0x%x (%i), class 0x%x (%i) list for location in <%"
801 PRIx64 ">%s", form, form, klass, klass,
802 (uint64_t) variable->dwarf_offset, variable->name);
805 // Handle start_scope:
806 if (dwarf_hasattr(die, DW_AT_start_scope)) {
807 Dwarf_Attribute attr;
808 dwarf_attr(die, DW_AT_start_scope, &attr);
809 int form = dwarf_whatform(&attr);
810 int klass = MC_dwarf_form_get_class(form);
812 case MC_DW_CLASS_CONSTANT:
815 variable->start_scope =
816 dwarf_formudata(&attr, &value) == 0 ? (size_t) value : 0;
819 case MC_DW_CLASS_RANGELISTPTR: // TODO
822 ("Unhandled form 0x%x, class 0x%X for DW_AT_start_scope of variable %s",
823 form, klass, name == NULL ? "?" : name);
827 if (ns && variable->global) {
828 char *old_name = variable->name;
829 variable->name = bprintf("%s::%s", ns, old_name);
832 // The current code needs a variable name,
833 // generate a fake one:
834 if (!variable->name) {
835 variable->name = bprintf("@anonymous#%i", mc_anonymous_variable_index++);
841 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die * die,
842 Dwarf_Die * unit, dw_frame_t frame,
845 dw_variable_t variable =
846 MC_die_to_variable(info, die, unit, frame, ns);
847 if (variable == NULL)
849 MC_dwarf_register_variable(info, frame, variable);
852 static void mc_frame_free_voipd(dw_frame_t * p)
858 static void MC_dwarf_handle_scope_die(mc_object_info_t info, Dwarf_Die * die,
859 Dwarf_Die * unit, dw_frame_t parent_frame,
862 // TODO, handle DW_TAG_type/DW_TAG_location for DW_TAG_with_stmt
863 int tag = dwarf_tag(die);
864 mc_tag_class klass = MC_dwarf_tag_classify(tag);
866 // (Template) Subprogram declaration:
867 if (klass == mc_tag_subprogram
868 && MC_dwarf_attr_flag(die, DW_AT_declaration, false))
871 if (klass == mc_tag_scope)
872 xbt_assert(parent_frame, "No parent scope for this scope");
874 dw_frame_t frame = xbt_new0(s_dw_frame_t, 1);
877 frame->id = dwarf_dieoffset(die);
878 frame->object_info = info;
880 if (klass == mc_tag_subprogram) {
881 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
883 ns ? bprintf("%s::%s", ns, name) : xbt_strdup(name);
886 frame->abstract_origin_id =
887 MC_dwarf_attr_dieoffset(die, DW_AT_abstract_origin);
889 // This is the base address for DWARF addresses.
890 // Relocated addresses are offset from this base address.
891 // See DWARF4 spec 7.5
892 void *base = MC_object_base_address(info);
894 // Variables are filled in the (recursive) call of MC_dwarf_handle_children:
896 xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
898 // TODO, support DW_AT_ranges
899 uint64_t low_pc = MC_dwarf_attr_integrate_addr(die, DW_AT_low_pc);
900 frame->low_pc = low_pc ? ((char *) base) + low_pc : 0;
903 Dwarf_Attribute attr;
904 if (!dwarf_attr_integrate(die, DW_AT_high_pc, &attr)) {
905 xbt_die("Missing DW_AT_high_pc matching with DW_AT_low_pc");
911 switch (MC_dwarf_form_get_class(dwarf_whatform(&attr))) {
913 // DW_AT_high_pc if an offset from the low_pc:
914 case MC_DW_CLASS_CONSTANT:
916 if (dwarf_formsdata(&attr, &offset) != 0)
917 xbt_die("Could not read constant");
918 frame->high_pc = (void *) ((char *) frame->low_pc + offset);
921 // DW_AT_high_pc is a relocatable address:
922 case MC_DW_CLASS_ADDRESS:
923 if (dwarf_formaddr(&attr, &high_pc) != 0)
924 xbt_die("Could not read address");
925 frame->high_pc = ((char *) base) + high_pc;
929 xbt_die("Unexpected class for DW_AT_high_pc");
934 if (klass == mc_tag_subprogram) {
935 Dwarf_Attribute attr_frame_base;
936 if (dwarf_attr_integrate(die, DW_AT_frame_base, &attr_frame_base))
937 mc_dwarf_location_list_init(&frame->frame_base, info, die,
942 xbt_dynar_new(sizeof(dw_frame_t), (void_f_pvoid_t) mc_frame_free_voipd);
945 if (klass == mc_tag_subprogram) {
946 char *key = bprintf("%" PRIx64, (uint64_t) frame->id);
947 xbt_dict_set(info->subprograms, key, frame, NULL);
949 } else if (klass == mc_tag_scope) {
950 xbt_dynar_push(parent_frame->scopes, &frame);
953 MC_dwarf_handle_children(info, die, unit, frame, ns);
956 static void mc_dwarf_handle_namespace_die(mc_object_info_t info,
957 Dwarf_Die * die, Dwarf_Die * unit,
961 const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name);
963 xbt_die("Unexpected namespace in a subprogram");
964 char *new_ns = ns == NULL ? xbt_strdup(name)
965 : bprintf("%s::%s", ns, name);
966 MC_dwarf_handle_children(info, die, unit, frame, new_ns);
970 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die * die,
971 Dwarf_Die * unit, dw_frame_t frame,
974 // For each child DIE:
977 for (res = dwarf_child(die, &child); res == 0;
978 res = dwarf_siblingof(&child, &child)) {
979 MC_dwarf_handle_die(info, &child, unit, frame, ns);
983 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die * die,
984 Dwarf_Die * unit, dw_frame_t frame,
987 int tag = dwarf_tag(die);
988 mc_tag_class klass = MC_dwarf_tag_classify(tag);
993 MC_dwarf_handle_type_die(info, die, unit, frame, ns);
996 // Subprogram or scope:
997 case mc_tag_subprogram:
999 MC_dwarf_handle_scope_die(info, die, unit, frame, ns);
1003 case mc_tag_variable:
1004 MC_dwarf_handle_variable_die(info, die, unit, frame, ns);
1007 case mc_tag_namespace:
1008 mc_dwarf_handle_namespace_die(info, die, unit, frame, ns);
1017 /** \brief Populate the debugging informations of the given ELF object
1019 * Read the DWARf information of the EFFL object and populate the
1020 * lists of types, variables, functions.
1022 void MC_dwarf_get_variables(mc_object_info_t info)
1024 int fd = open(info->file_name, O_RDONLY);
1026 xbt_die("Could not open file %s", info->file_name);
1028 Dwarf *dwarf = dwarf_begin(fd, DWARF_C_READ);
1029 if (dwarf == NULL) {
1030 xbt_die("Your program must be compiled with -g (%s)", info->file_name);
1032 // For each compilation unit:
1033 Dwarf_Off offset = 0;
1034 Dwarf_Off next_offset = 0;
1036 while (dwarf_nextcu(dwarf, offset, &next_offset, &length, NULL, NULL, NULL) ==
1039 if (dwarf_offdie(dwarf, offset + length, &unit_die) != NULL) {
1041 // For each child DIE:
1044 for (res = dwarf_child(&unit_die, &child); res == 0;
1045 res = dwarf_siblingof(&child, &child)) {
1046 MC_dwarf_handle_die(info, &child, &unit_die, NULL, NULL);
1050 offset = next_offset;
1057 /************************** Free functions *************************/
1059 void mc_frame_free(dw_frame_t frame)
1061 xbt_free(frame->name);
1062 mc_dwarf_location_list_clear(&(frame->frame_base));
1063 xbt_dynar_free(&(frame->variables));
1064 xbt_dynar_free(&(frame->scopes));
1068 void dw_type_free(dw_type_t t)
1071 xbt_free(t->dw_type_id);
1072 xbt_dynar_free(&(t->members));
1073 mc_dwarf_expression_clear(&t->location);
1077 void dw_variable_free(dw_variable_t v)
1081 xbt_free(v->type_origin);
1083 if (v->locations.locations)
1084 mc_dwarf_location_list_clear(&v->locations);
1089 void dw_variable_free_voidp(void *t)
1091 dw_variable_free((dw_variable_t) * (void **) t);
1094 // ***** object_info
1098 mc_object_info_t MC_new_object_info(void)
1100 mc_object_info_t res = xbt_new0(s_mc_object_info_t, 1);
1101 res->subprograms = xbt_dict_new_homogeneous((void (*)(void *)) mc_frame_free);
1102 res->global_variables =
1103 xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
1104 res->types = xbt_dict_new_homogeneous((void (*)(void *)) dw_type_free);
1105 res->full_types_by_name = xbt_dict_new_homogeneous(NULL);
1109 void MC_free_object_info(mc_object_info_t * info)
1111 xbt_free(&(*info)->file_name);
1112 xbt_dict_free(&(*info)->subprograms);
1113 xbt_dynar_free(&(*info)->global_variables);
1114 xbt_dict_free(&(*info)->types);
1115 xbt_dict_free(&(*info)->full_types_by_name);
1117 xbt_dynar_free(&(*info)->functions_index);
1123 void *MC_object_base_address(mc_object_info_t info)
1125 if (info->flags & MC_OBJECT_INFO_EXECUTABLE)
1127 void *result = info->start_exec;
1128 if (info->start_rw != NULL && result > (void *) info->start_rw)
1129 result = info->start_rw;
1130 if (info->start_ro != NULL && result > (void *) info->start_ro)
1131 result = info->start_ro;
1135 // ***** Functions index
1137 static int MC_compare_frame_index_items(mc_function_index_item_t a,
1138 mc_function_index_item_t b)
1140 if (a->low_pc < b->low_pc)
1142 else if (a->low_pc == b->low_pc)
1148 static void MC_make_functions_index(mc_object_info_t info)
1150 xbt_dynar_t index = xbt_dynar_new(sizeof(s_mc_function_index_item_t), NULL);
1152 // Populate the array:
1153 dw_frame_t frame = NULL;
1154 xbt_dict_cursor_t cursor;
1156 xbt_dict_foreach(info->subprograms, cursor, key, frame) {
1157 if (frame->low_pc == NULL)
1159 s_mc_function_index_item_t entry;
1160 entry.low_pc = frame->low_pc;
1161 entry.high_pc = frame->high_pc;
1162 entry.function = frame;
1163 xbt_dynar_push(index, &entry);
1166 mc_function_index_item_t base =
1167 (mc_function_index_item_t) xbt_dynar_get_ptr(index, 0);
1169 // Sort the array by low_pc:
1171 xbt_dynar_length(index),
1172 sizeof(s_mc_function_index_item_t),
1173 (int (*)(const void *, const void *)) MC_compare_frame_index_items);
1175 info->functions_index = index;
1178 static void MC_post_process_variables(mc_object_info_t info)
1180 unsigned cursor = 0;
1181 dw_variable_t variable = NULL;
1182 xbt_dynar_foreach(info->global_variables, cursor, variable) {
1183 if (variable->type_origin) {
1184 variable->type = (dw_type_t) xbt_dict_get_or_null(info->types, variable->type_origin);
1189 static void mc_post_process_scope(mc_object_info_t info, dw_frame_t scope)
1192 if (scope->tag == DW_TAG_inlined_subroutine) {
1194 // Attach correct namespaced name in inlined subroutine:
1195 char *key = bprintf("%" PRIx64, (uint64_t) scope->abstract_origin_id);
1196 dw_frame_t abstract_origin = (dw_frame_t) xbt_dict_get_or_null(info->subprograms, key);
1197 xbt_assert(abstract_origin, "Could not lookup abstract origin %s", key);
1199 scope->name = xbt_strdup(abstract_origin->name);
1203 unsigned cursor = 0;
1204 dw_variable_t variable = NULL;
1205 xbt_dynar_foreach(scope->variables, cursor, variable) {
1206 if (variable->type_origin) {
1207 variable->type = (dw_type_t) xbt_dict_get_or_null(info->types, variable->type_origin);
1211 // Recursive post-processing of nested-scopes:
1212 dw_frame_t nested_scope = NULL;
1213 xbt_dynar_foreach(scope->scopes, cursor, nested_scope)
1214 mc_post_process_scope(info, nested_scope);
1218 static void MC_post_process_functions(mc_object_info_t info)
1220 xbt_dict_cursor_t cursor;
1222 dw_frame_t subprogram = NULL;
1223 xbt_dict_foreach(info->subprograms, cursor, key, subprogram) {
1224 mc_post_process_scope(info, subprogram);
1229 /** \brief Fill/lookup the "subtype" field.
1231 static void MC_resolve_subtype(mc_object_info_t info, dw_type_t type)
1234 if (type->dw_type_id == NULL)
1236 type->subtype = (dw_type_t) xbt_dict_get_or_null(info->types, type->dw_type_id);
1237 if (type->subtype == NULL)
1239 if (type->subtype->byte_size != 0)
1241 if (type->subtype->name == NULL)
1243 // Try to find a more complete description of the type:
1244 // We need to fix in order to support C++.
1247 (dw_type_t) xbt_dict_get_or_null(info->full_types_by_name, type->subtype->name);
1248 if (subtype != NULL) {
1249 type->subtype = subtype;
1254 static void MC_post_process_types(mc_object_info_t info)
1256 xbt_dict_cursor_t cursor = NULL;
1260 // Lookup "subtype" field:
1261 xbt_dict_foreach(info->types, cursor, origin, type) {
1262 MC_resolve_subtype(info, type);
1266 if (type->members != NULL)
1267 xbt_dynar_foreach(type->members, i, member) {
1268 MC_resolve_subtype(info, member);
1273 /** \brief Finds informations about a given shared object/executable */
1274 mc_object_info_t MC_find_object_info(memory_map_t maps, const char *name,
1277 mc_object_info_t result = MC_new_object_info();
1279 result->flags |= MC_OBJECT_INFO_EXECUTABLE;
1280 result->file_name = xbt_strdup(name);
1281 MC_find_object_address(maps, result);
1282 MC_dwarf_get_variables(result);
1283 MC_post_process_types(result);
1284 MC_post_process_variables(result);
1285 MC_post_process_functions(result);
1286 MC_make_functions_index(result);
1290 /*************************************************************************/
1292 static int MC_dwarf_get_variable_index(xbt_dynar_t variables, char *var,
1296 if (xbt_dynar_is_empty(variables))
1299 unsigned int cursor = 0;
1301 int end = xbt_dynar_length(variables) - 1;
1302 dw_variable_t var_test = NULL;
1304 while (start <= end) {
1305 cursor = (start + end) / 2;
1307 (dw_variable_t) xbt_dynar_get_as(variables, cursor, dw_variable_t);
1308 if (strcmp(var_test->name, var) < 0) {
1310 } else if (strcmp(var_test->name, var) > 0) {
1313 if (address) { /* global variable */
1314 if (var_test->address == address)
1316 if (var_test->address > address)
1320 } else { /* local variable */
1326 if (strcmp(var_test->name, var) == 0) {
1327 if (address && var_test->address < address)
1331 } else if (strcmp(var_test->name, var) < 0)
1338 void MC_dwarf_register_global_variable(mc_object_info_t info,
1339 dw_variable_t variable)
1342 MC_dwarf_get_variable_index(info->global_variables, variable->name,
1345 xbt_dynar_insert_at(info->global_variables, index, &variable);
1349 void MC_dwarf_register_non_global_variable(mc_object_info_t info,
1351 dw_variable_t variable)
1353 xbt_assert(frame, "Frame is NULL");
1355 MC_dwarf_get_variable_index(frame->variables, variable->name, NULL);
1357 xbt_dynar_insert_at(frame->variables, index, &variable);
1361 void MC_dwarf_register_variable(mc_object_info_t info, dw_frame_t frame,
1362 dw_variable_t variable)
1364 if (variable->global)
1365 MC_dwarf_register_global_variable(info, variable);
1366 else if (frame == NULL)
1367 xbt_die("No frame for this local variable");
1369 MC_dwarf_register_non_global_variable(info, frame, variable);
1372 void MC_post_process_object_info(mc_process_t process, mc_object_info_t info)
1374 xbt_dict_cursor_t cursor = NULL;
1376 dw_type_t type = NULL;
1377 xbt_dict_foreach(info->types, cursor, key, type) {
1379 dw_type_t subtype = type;
1380 while (subtype->type == DW_TAG_typedef || subtype->type == DW_TAG_volatile_type
1381 || subtype->type == DW_TAG_const_type) {
1382 if (subtype->subtype)
1383 subtype = subtype->subtype;
1388 // Resolve full_type:
1389 if (subtype->name && subtype->byte_size == 0) {
1390 for (size_t i = 0; i != process->object_infos_size; ++i) {
1391 dw_type_t same_type = (dw_type_t)
1392 xbt_dict_get_or_null(process->object_infos[i]->full_types_by_name,
1394 if (same_type && same_type->name && same_type->byte_size) {
1395 type->full_type = same_type;
1399 } else type->full_type = subtype;