1 /* Copyright (c) 2008-2013. The SimGrid Team.
2 * All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
8 #include <elfutils/libdw.h>
11 #include <simgrid_config.h>
13 #include <xbt/sysdep.h>
15 #include "mc_private.h"
17 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dwarf, mc, "DWARF processing");
19 /** \brief The default DW_TAG_lower_bound for a given DW_AT_language.
21 * The default for a given language is defined in the DWARF spec.
23 * \param language consant as defined by the DWARf spec
25 static uint64_t MC_dwarf_default_lower_bound(int lang);
27 /** \brief Computes the the element_count of a DW_TAG_enumeration_type DIE
29 * This is the number of elements in a given array dimension.
31 * A reference of the compilation unit (DW_TAG_compile_unit) is
32 * needed because the default lower bound (when there is no DW_AT_lower_bound)
33 * depends of the language of the compilation unit (DW_AT_language).
35 * \param die DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type
36 * \param unit DIE of the DW_TAG_compile_unit
38 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit);
40 /** \brief Computes the number of elements of a given DW_TAG_array_type.
42 * \param die DIE for the DW_TAG_array_type
44 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit);
46 /** \brief Process a DIE
48 * \param info the resulting object fot the library/binary file (output)
49 * \param die the current DIE
50 * \param unit the DIE of the compile unit of the current DIE
51 * \param frame containg frame if any
53 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame);
55 /** \brief Process a type DIE
57 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit);
59 /** \brief Calls MC_dwarf_handle_die on all childrend of the given die
61 * \param info the resulting object fot the library/binary file (output)
62 * \param die the current DIE
63 * \param unit the DIE of the compile unit of the current DIE
64 * \param frame containg frame if any
66 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame);
68 /** \brief Handle a variable (DW_TAG_variable or other)
70 * \param info the resulting object fot the library/binary file (output)
71 * \param die the current DIE
72 * \param unit the DIE of the compile unit of the current DIE
73 * \param frame containg frame if any
75 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame);
77 /** \brief Convert a libdw DWARF expression into a MC representation of the location
79 * \param expr array of DWARf operations
80 * \param len number of elements
81 * \return a new MC expression
83 static dw_location_t MC_dwarf_get_expression(Dwarf_Op* expr, size_t len);
85 /** \brief Get the DW_TAG_type of the DIE
88 * \return DW_TAG_type attribute as a new string (NULL if none)
90 static char* MC_dwarf_at_type(Dwarf_Die* die);
92 /** \brief Get the name of an attribute (DW_AT_*) from its code
94 * \param attr attribute code (see the DWARF specification)
95 * \return name of the attribute
97 const char* MC_dwarf_attrname(int attr) {
99 #include "mc_dwarf_attrnames.h"
101 return "DW_AT_unkown";
105 /** \brief Get the name of a dwarf tag (DW_TAG_*) from its code
107 * \param tag tag code (see the DWARF specification)
108 * \return name of the tag
110 const char* MC_dwarf_tagname(int tag) {
112 #include "mc_dwarf_tagnames.h"
114 return "DW_TAG_invalid";
116 return "DW_TAG_unkown";
120 #define MC_DW_CLASS_UNKNOWN 0
121 #define MC_DW_CLASS_ADDRESS 1 // Location in the address space of the program
122 #define MC_DW_CLASS_BLOCK 2 // Arbitrary block of bytes
123 #define MC_DW_CLASS_CONSTANT 3
124 #define MC_DW_CLASS_STRING 3 // String
125 #define MC_DW_CLASS_FLAG 4 // Boolean
126 #define MC_DW_CLASS_REFERENCE 5 // Reference to another DIE
127 #define MC_DW_CLASS_EXPRLOC 6 // DWARF expression/location description
128 #define MC_DW_CLASS_LINEPTR 7
129 #define MC_DW_CLASS_LOCLISTPTR 8
130 #define MC_DW_CLASS_MACPTR 9
131 #define MC_DW_CLASS_RANGELISTPTR 10
133 static int MC_dwarf_form_get_class(int form) {
136 return MC_DW_CLASS_ADDRESS;
141 return MC_DW_CLASS_BLOCK;
147 return MC_DW_CLASS_CONSTANT;
150 return MC_DW_CLASS_STRING;
151 case DW_FORM_ref_addr:
156 case DW_FORM_ref_udata:
157 return MC_DW_CLASS_REFERENCE;
159 case DW_FORM_flag_present:
160 return MC_DW_CLASS_FLAG;
161 case DW_FORM_exprloc:
162 return MC_DW_CLASS_EXPRLOC;
166 return MC_DW_CLASS_UNKNOWN;
170 /** \brief Get the name of the tag of a given DIE
173 * \return name of the tag of this DIE
175 static inline const char* MC_dwarf_die_tagname(Dwarf_Die* die) {
176 return MC_dwarf_tagname(dwarf_tag(die));
181 /** \brief Get an attribute of a given DIE as a string
184 * \param attribute attribute
185 * \return value of the given attribute of the given DIE
187 static const char* MC_dwarf_attr_string(Dwarf_Die* die, int attribute) {
188 Dwarf_Attribute attr;
189 if (!dwarf_attr_integrate(die, attribute, &attr)) {
192 return dwarf_formstring(&attr);
196 /** \brief Get the linkage name of a DIE.
198 * Use either DW_AT_linkage_name or DW_AR_MIPS_linkage_name.
201 * \return linkage name of the given DIE (or NULL)
203 static const char* MC_dwarf_at_linkage_name(Dwarf_Die* die) {
204 const char* name = MC_dwarf_attr_string(die, DW_AT_linkage_name);
206 name = MC_dwarf_attr_string(die, DW_AT_MIPS_linkage_name);
210 /** \brief Create a location list from a given attribute
213 * \param attr the attribute
214 * \return MC specific representation of the location list represented by the given attribute
217 static dw_location_t MC_dwarf_get_location_list(mc_object_info_t info, Dwarf_Die* die, Dwarf_Attribute* attr) {
219 dw_location_t location = xbt_new0(s_dw_location_t, 1);
220 location->type = e_dw_loclist;
221 xbt_dynar_t loclist = xbt_dynar_new(sizeof(dw_location_entry_t), NULL);
222 location->location.loclist = loclist;
224 ptrdiff_t offset = 0;
225 Dwarf_Addr base, start, end;
231 offset = dwarf_getlocations(attr, offset, &base, &start, &end, &expr, &len);
235 xbt_die("Error while loading location list");
237 dw_location_entry_t new_entry = xbt_new0(s_dw_location_entry_t, 1);
239 void* base = info->flags & MC_OBJECT_INFO_EXECUTABLE ? 0 : MC_object_base_address(info);
241 new_entry->lowpc = (char*) base + start;
242 new_entry->highpc = (char*) base + end;
243 new_entry->location = MC_dwarf_get_expression(expr, len);
245 xbt_dynar_push(loclist, &new_entry);
250 /** \brief Get the location expression or location list from an attribute
252 * Processes direct expressions as well as location lists.
255 * \param attr the attribute
256 * \return MC specific representation of the location represented by the given attribute
259 static dw_location_t MC_dwarf_get_location(mc_object_info_t info, Dwarf_Die* die, Dwarf_Attribute* attr) {
260 int form = dwarf_whatform(attr);
263 // The attribute is an DWARF location expression:
264 case DW_FORM_exprloc:
265 case DW_FORM_block1: // not in the spec
272 if (dwarf_getlocation(attr, &expr, &len))
273 xbt_die("Could not read location expression");
274 return MC_dwarf_get_expression(expr, len);
277 // The attribute is a reference to a location list entry:
278 case DW_FORM_sec_offset:
283 return MC_dwarf_get_location_list(info, die, attr);
288 xbt_die("Unexpected form %i list for location in attribute %s of <%p>%s",
290 MC_dwarf_attrname(attr->code),
291 (void*) dwarf_dieoffset(die),
292 MC_dwarf_attr_string(die, DW_AT_name));
297 /** \brief Get the location expression or location list from an attribute
299 * Processes direct expressions as well as location lists.
302 * \param attribute the attribute code
303 * \return MC specific representation of the location represented by the given attribute
306 static dw_location_t MC_dwarf_at_location(mc_object_info_t info, Dwarf_Die* die, int attribute) {
307 if(!dwarf_hasattr_integrate(die, attribute))
308 return xbt_new0(s_dw_location_t, 1);
310 Dwarf_Attribute attr;
311 dwarf_attr_integrate(die, attribute, &attr);
312 return MC_dwarf_get_location(info, die, &attr);
315 static char* MC_dwarf_at_type(Dwarf_Die* die) {
316 Dwarf_Attribute attr;
317 if (dwarf_hasattr_integrate(die, DW_AT_type)) {
318 dwarf_attr_integrate(die, DW_AT_type, &attr);
319 Dwarf_Die subtype_die;
320 if (dwarf_formref_die(&attr, &subtype_die)==NULL) {
321 xbt_die("Could not find DIE for type");
323 Dwarf_Off subtype_global_offset = dwarf_dieoffset(&subtype_die);
324 return bprintf("%" PRIx64 , subtype_global_offset);
329 static uint64_t MC_dwarf_attr_addr(Dwarf_Die* die, int attribute) {
330 Dwarf_Attribute attr;
331 if(dwarf_attr_integrate(die, attribute, &attr)==NULL)
334 if (dwarf_formaddr(&attr, &value) == 0)
335 return (uint64_t) value;
340 static uint64_t MC_dwarf_attr_uint(Dwarf_Die* die, int attribute, uint64_t default_value) {
341 Dwarf_Attribute attr;
342 if (dwarf_attr_integrate(die, attribute, &attr)==NULL)
343 return default_value;
345 return dwarf_formudata(dwarf_attr_integrate(die, attribute, &attr), &value) == 0 ? (uint64_t) value : default_value;
348 static bool MC_dwarf_attr_flag(Dwarf_Die* die, int attribute, int integrate) {
349 Dwarf_Attribute attr;
350 if ((integrate ? dwarf_attr_integrate(die, attribute, &attr)
351 : dwarf_attr(die, attribute, &attr))==0)
355 if (dwarf_formflag(&attr, &result))
356 xbt_die("Unexpected form for attribute %s",
357 MC_dwarf_attrname(attribute));
361 static uint64_t MC_dwarf_default_lower_bound(int lang) {
366 case DW_LANG_C_plus_plus:
370 case DW_LANG_ObjC_plus_plus:
376 case DW_LANG_Fortran77:
377 case DW_LANG_Fortran90:
378 case DW_LANG_Fortran95:
379 case DW_LANG_Modula2:
380 case DW_LANG_Pascal83:
382 case DW_LANG_Cobol74:
383 case DW_LANG_Cobol85:
386 xbt_die("No default MT_TAG_lower_bound for language %i and none given", lang);
391 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
392 xbt_assert(dwarf_tag(die)==DW_TAG_enumeration_type ||dwarf_tag(die)==DW_TAG_subrange_type,
393 "MC_dwarf_subrange_element_count called with DIE of type %s", MC_dwarf_die_tagname(die));
395 // Use DW_TAG_count if present:
396 if (dwarf_hasattr_integrate(die, DW_AT_count)) {
397 return MC_dwarf_attr_uint(die, DW_AT_count, 0);
400 // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound + 1:
402 if (!dwarf_hasattr_integrate(die, DW_AT_upper_bound)) {
403 // This is not really 0, but the code expects this (we do not know):
406 uint64_t upper_bound = MC_dwarf_attr_uint(die, DW_AT_upper_bound, -1);
408 uint64_t lower_bound = 0;
409 if (dwarf_hasattr_integrate(die, DW_AT_lower_bound)) {
410 lower_bound = MC_dwarf_attr_uint(die, DW_AT_lower_bound, -1);
412 lower_bound = MC_dwarf_default_lower_bound(dwarf_srclang(unit));
414 return upper_bound - lower_bound + 1;
417 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
418 xbt_assert(dwarf_tag(die)==DW_TAG_array_type,
419 "MC_dwarf_array_element_count called with DIE of type %s", MC_dwarf_die_tagname(die));
424 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
425 int child_tag = dwarf_tag(&child);
426 if (child_tag==DW_TAG_subrange_type ||child_tag==DW_TAG_enumeration_type) {
427 result *= MC_dwarf_subrange_element_count(&child, unit);
435 Dwarf_Off MC_dwarf_resolve_location(unw_cursor_t* c, dw_location_t location, void* frame_pointer_address) {
437 switch (location->type){
439 if (xbt_dynar_length(location->location.compose) > 1){
440 return 0; /* TODO : location list with optimizations enabled */
442 dw_location_t location_entry = xbt_dynar_get_as(location->location.compose, 0, dw_location_t);
443 switch (location_entry->type){
445 unw_get_reg(c, location_entry->location.reg, &res);
447 case e_dw_bregister_op:
448 unw_get_reg(c, location_entry->location.breg_op.reg, &res);
449 return (Dwarf_Off) ((long)res + location_entry->location.breg_op.offset);
451 case e_dw_fbregister_op:
452 if (frame_pointer_address != NULL)
453 return (Dwarf_Off)((char *)frame_pointer_address + location_entry->location.fbreg_op);
457 return 0; /* FIXME : implement other cases (with optimizations enabled) */
467 static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member, Dwarf_Die* child) {
468 if (dwarf_hasattr(child, DW_AT_data_bit_offset)) {
469 xbt_die("Can't groke DW_AT_data_bit_offset.");
472 if (!dwarf_hasattr_integrate(child, DW_AT_data_member_location)) {
473 if (type->type != DW_TAG_union_type) {
475 "Missing DW_AT_data_member_location field in DW_TAG_member %s of type <%p>%s",
476 member->name, type->id, type->name);
482 Dwarf_Attribute attr;
483 dwarf_attr_integrate(child, DW_AT_data_member_location, &attr);
484 int klass = MC_dwarf_form_get_class(dwarf_whatform(&attr));
486 case MC_DW_CLASS_EXPRLOC:
487 case MC_DW_CLASS_BLOCK:
488 // Location expression:
492 if (dwarf_getlocation(&attr, &expr, &len)) {
494 "Could not read location expression DW_AT_data_member_location in DW_TAG_member %s of type <%p>%s",
495 MC_dwarf_attr_string(child, DW_AT_name),
496 type->id, type->name);
498 if (len==1 && expr[0].atom == DW_OP_plus_uconst) {
499 member->offset = expr[0].number;
501 xbt_die("Can't groke this location expression yet.");
505 case MC_DW_CLASS_CONSTANT:
506 // Offset from the base address of the object:
509 if (!dwarf_formudata(&attr, &offset))
510 member->offset = offset;
512 xbt_die("Cannot get %s location <%p>%s",
513 MC_dwarf_attr_string(child, DW_AT_name),
514 type->id, type->name);
517 case MC_DW_CLASS_LOCLISTPTR:
518 // Reference to a location list:
520 case MC_DW_CLASS_REFERENCE:
521 // It's supposed to be possible in DWARF2 but I couldn't find its semantic
524 xbt_die("Can't handle form class 0x%x (%i) as DW_AT_member_location", klass, klass);
529 static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_type_t type) {
532 xbt_assert(!type->members);
533 type->members = xbt_dynar_new(sizeof(dw_type_t), (void(*)(void*))dw_type_free);
534 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
535 if (dwarf_tag(&child)==DW_TAG_member) {
536 // TODO, we should use another type (because is is not a type but a member)
537 dw_type_t member = xbt_new0(s_dw_type_t, 1);
541 const char* name = MC_dwarf_attr_string(&child, DW_AT_name);
543 member->name = xbt_strdup(name);
547 member->byte_size = MC_dwarf_attr_uint(&child, DW_AT_byte_size, 0);
548 member->element_count = -1;
549 member->dw_type_id = MC_dwarf_at_type(&child);
550 member->members = NULL;
551 member->is_pointer_type = 0;
554 if(dwarf_hasattr(&child, DW_AT_data_bit_offset)) {
555 xbt_die("Can't groke DW_AT_data_bit_offset.");
558 MC_dwarf_fill_member_location(type, member, &child);
560 if (!member->dw_type_id) {
561 xbt_die("Missing type for member %s of <%p>%s", member->name, type->id, type->name);
564 xbt_dynar_push(type->members, &member);
569 /** \brief Create a MC type object from a DIE
571 * \param info current object info object
572 * \param DIE (for a given type);
573 * \param unit compilation unit of the current DIE
574 * \return MC representation of the type
576 static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit) {
578 dw_type_t type = xbt_new0(s_dw_type_t, 1);
583 type->element_count = -1;
584 type->dw_type_id = NULL;
585 type->members = NULL;
586 type->is_pointer_type = 0;
589 type->type = dwarf_tag(die);
592 type->id = (void *) dwarf_dieoffset(die);
594 const char* name = MC_dwarf_attr_string(die, DW_AT_name);
596 type->name = xbt_strdup(name);
599 XBT_DEBUG("Processing type <%p>%s", type->id, type->name);
601 type->dw_type_id = MC_dwarf_at_type(die);
603 // Computation of the byte_size;
604 if (dwarf_hasattr_integrate(die, DW_AT_byte_size))
605 type->byte_size = MC_dwarf_attr_uint(die, DW_AT_byte_size, 0);
606 else if (type->type == DW_TAG_array_type || type->type==DW_TAG_structure_type || type->type==DW_TAG_class_type) {
608 if (dwarf_aggregate_size(die, &size)==0) {
609 type->byte_size = size;
613 switch (type->type) {
614 case DW_TAG_array_type:
615 type->element_count = MC_dwarf_array_element_count(die, unit);
616 // TODO, handle DW_byte_stride and (not) DW_bit_stride
619 case DW_TAG_pointer_type:
620 case DW_TAG_reference_type:
621 case DW_TAG_rvalue_reference_type:
622 type->is_pointer_type = 1;
625 case DW_TAG_structure_type:
626 case DW_TAG_union_type:
627 case DW_TAG_class_type:
628 MC_dwarf_add_members(info, die, unit, type);
634 static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit) {
635 dw_type_t type = MC_dwarf_die_to_type(info, die, unit);
637 char* key = bprintf("%" PRIx64, (uint64_t) type->id);
638 xbt_dict_set(info->types, key, type, NULL);
640 if(type->name && type->byte_size!=0) {
641 xbt_dict_set(info->types_by_name, type->name, type, NULL);
645 /** \brief Convert libdw location expresion elment into native one (or NULL in some cases) */
646 static dw_location_t MC_dwarf_get_expression_element(Dwarf_Op* op) {
647 dw_location_t element = xbt_new0(s_dw_location_t, 1);
648 uint8_t atom = op->atom;
649 if (atom >= DW_OP_reg0 && atom<= DW_OP_reg31) {
650 element->type = e_dw_register;
651 element->location.reg = atom - DW_OP_reg0;
653 else if (atom >= DW_OP_breg0 && atom<= DW_OP_breg31) {
654 element->type = e_dw_bregister_op;
655 element->location.reg = atom - DW_OP_breg0;
656 element->location.breg_op.offset = op->number;
658 else if (atom >= DW_OP_lit0 && atom<= DW_OP_lit31) {
659 element->type = e_dw_lit;
660 element->location.reg = atom - DW_OP_lit0;
664 element->type = e_dw_fbregister_op;
665 element->location.fbreg_op = op->number;
668 element->type = e_dw_piece;
669 element->location.piece = op->number;
671 case DW_OP_plus_uconst:
672 element->type = e_dw_plus_uconst;
673 element->location.plus_uconst = op->number;
676 element->type = e_dw_arithmetic;
677 element->location.arithmetic = xbt_strdup("abs");
680 element->type = e_dw_arithmetic;
681 element->location.arithmetic = xbt_strdup("and");
684 element->type = e_dw_arithmetic;
685 element->location.arithmetic = xbt_strdup("div");
688 element->type = e_dw_arithmetic;
689 element->location.arithmetic = xbt_strdup("minus");
692 element->type = e_dw_arithmetic;
693 element->location.arithmetic = xbt_strdup("mod");
696 element->type = e_dw_arithmetic;
697 element->location.arithmetic = xbt_strdup("mul");
700 element->type = e_dw_arithmetic;
701 element->location.arithmetic = xbt_strdup("neg");
704 element->type = e_dw_arithmetic;
705 element->location.arithmetic = xbt_strdup("not");
708 element->type = e_dw_arithmetic;
709 element->location.arithmetic = xbt_strdup("or");
712 element->type = e_dw_arithmetic;
713 element->location.arithmetic = xbt_strdup("plus");
716 case DW_OP_stack_value:
721 case DW_OP_deref_size:
722 element->type = e_dw_deref;
723 element->location.deref_size = (unsigned int short) op->number;
726 element->type = e_dw_deref;
727 element->location.deref_size = sizeof(void *);
730 element->type = e_dw_uconstant;
731 element->location.uconstant.bytes = 1;
732 element->location.uconstant.value = (unsigned long int) op->number;
735 element->type = e_dw_sconstant;
736 element->location.uconstant.bytes = 1;
737 element->location.uconstant.value = (unsigned long int) op->number;
741 element->type = e_dw_uconstant;
742 element->location.uconstant.bytes = 1;
743 element->location.uconstant.value = (unsigned long int) op->number;
746 element->type = e_dw_uconstant;
747 element->location.uconstant.bytes = 2;
748 element->location.uconstant.value = (unsigned long int) op->number;
751 element->type = e_dw_uconstant;
752 element->location.uconstant.bytes = 4;
753 element->location.uconstant.value = (unsigned long int) op->number;
756 element->type = e_dw_uconstant;
757 element->location.uconstant.bytes = 8;
758 element->location.uconstant.value = (unsigned long int) op->number;
762 element->type = e_dw_sconstant;
763 element->location.uconstant.bytes = 1;
764 element->location.uconstant.value = (unsigned long int) op->number;
767 element->type = e_dw_sconstant;
768 element->location.uconstant.bytes = 2;
769 element->location.uconstant.value = (unsigned long int) op->number;
772 element->type = e_dw_sconstant;
773 element->location.uconstant.bytes = 4;
774 element->location.uconstant.value = (unsigned long int) op->number;
777 element->type = e_dw_sconstant;
778 element->location.uconstant.bytes = 8;
779 element->location.uconstant.value = (unsigned long int) op->number;
782 element->type = e_dw_unsupported;
788 /** \brief Convert libdw location expresion into native one */
789 static dw_location_t MC_dwarf_get_expression(Dwarf_Op* expr, size_t len) {
790 dw_location_t loc = xbt_new0(s_dw_location_t, 1);
791 loc->type = e_dw_compose;
792 loc->location.compose = xbt_dynar_new(sizeof(dw_location_t), NULL);
795 for (i=0; i!=len; ++i) {
796 dw_location_t element = MC_dwarf_get_expression_element(expr+i);
798 xbt_dynar_push(loc->location.compose, &element);
804 static int mc_anonymous_variable_index = 0;
806 static dw_variable_t MC_die_to_variable(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame) {
808 if (MC_dwarf_attr_flag(die, DW_AT_declaration, false))
811 Dwarf_Attribute attr_location;
812 if (dwarf_attr(die, DW_AT_location, &attr_location)==NULL) {
813 // No location: do not add it ?
817 dw_variable_t variable = xbt_new0(s_dw_variable_t, 1);
818 variable->dwarf_offset = dwarf_dieoffset(die);
819 variable->global = frame == NULL; // Can be override base on DW_AT_location
820 variable->name = xbt_strdup(MC_dwarf_attr_string(die, DW_AT_name));
821 variable->type_origin = MC_dwarf_at_type(die);
823 int klass = MC_dwarf_form_get_class(dwarf_whatform(&attr_location));
825 case MC_DW_CLASS_EXPRLOC:
826 case MC_DW_CLASS_BLOCK:
827 // Location expression:
831 if (dwarf_getlocation(&attr_location, &expr, &len)) {
833 "Could not read location expression in DW_AT_location of variable <%p>%s",
834 (void*) variable->dwarf_offset, variable->name);
837 if (len==1 && expr[0].atom == DW_OP_addr) {
838 variable->global = 1;
839 Dwarf_Off offset = expr[0].number;
840 // TODO, Why is this different base on the object?
841 Dwarf_Off base = strcmp(info->file_name, xbt_binary_name) !=0 ? (Dwarf_Off) info->start_exec : 0;
842 variable->address = (void*) (base + offset);
844 variable->location = MC_dwarf_get_expression(expr, len);
849 case MC_DW_CLASS_LOCLISTPTR:
850 case MC_DW_CLASS_CONSTANT:
851 // Reference to location list:
852 variable->location = MC_dwarf_get_location_list(info, die, &attr_location);
855 xbt_die("Unexpected calss 0x%x (%i) list for location in <%p>%s",
856 klass, klass, (void*) variable->dwarf_offset, variable->name);
859 // The current code needs a variable name,
860 // generate a fake one:
861 if(!variable->name) {
862 variable->name = bprintf("@anonymous#%i", mc_anonymous_variable_index++);
868 static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame) {
869 dw_variable_t variable = MC_die_to_variable(info, die, unit, frame);
872 MC_dwarf_register_variable(info, frame, variable);
875 static void MC_dwarf_handle_subprogram_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t parent_frame) {
876 dw_frame_t frame = xbt_new0(s_dw_frame_t, 1);
878 frame->start = dwarf_dieoffset(die);
880 const char* name = MC_dwarf_at_linkage_name(die);
882 name = MC_dwarf_attr_string(die, DW_AT_name);
883 frame->name = xbt_strdup(name);
885 // This is the base address for DWARF addresses.
886 // Relocated addresses are offset from this base address.
887 // See DWARF4 spec 7.5
888 void* base = info->flags & MC_OBJECT_INFO_EXECUTABLE ? 0 : MC_object_base_address(info);
890 // Variables are filled in the (recursive) call of MC_dwarf_handle_children:
891 frame->variables = xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
892 frame->high_pc = ((char*) base) + MC_dwarf_attr_addr(die, DW_AT_high_pc);
893 frame->low_pc = ((char*) base) + MC_dwarf_attr_addr(die, DW_AT_low_pc);
894 frame->frame_base = MC_dwarf_at_location(info, die, DW_AT_frame_base);
895 frame->end = -1; // This one is now useless:
898 MC_dwarf_handle_children(info, die, unit, frame);
901 xbt_dict_set(info->local_variables, frame->name, frame, NULL);
904 static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame) {
907 for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
908 MC_dwarf_handle_die(info, &child, unit, frame);
912 static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame) {
913 int tag = dwarf_tag(die);
915 case DW_TAG_array_type:
916 case DW_TAG_class_type:
917 case DW_TAG_enumeration_type:
919 case DW_TAG_pointer_type:
920 case DW_TAG_string_type:
921 case DW_TAG_structure_type:
922 case DW_TAG_subroutine_type:
923 case DW_TAG_union_type:
924 case DW_TAG_ptr_to_member_type:
925 case DW_TAG_set_type:
926 case DW_TAG_subrange_type:
927 case DW_TAG_base_type:
928 case DW_TAG_const_type:
929 case DW_TAG_file_type:
930 case DW_TAG_packed_type:
931 case DW_TAG_volatile_type:
932 case DW_TAG_restrict_type:
933 case DW_TAG_interface_type:
934 case DW_TAG_unspecified_type:
935 case DW_TAG_mutable_type:
936 case DW_TAG_shared_type:
937 MC_dwarf_handle_type_die(info, die, unit);
939 case DW_TAG_subprogram:
940 MC_dwarf_handle_subprogram_die(info, die, unit, frame);
942 // case DW_TAG_formal_parameter:
943 case DW_TAG_variable:
944 case DW_TAG_formal_parameter:
945 MC_dwarf_handle_variable_die(info, die, unit, frame);
949 // Recursive processing of children DIE:
950 MC_dwarf_handle_children(info, die, unit, frame);
953 void MC_dwarf_get_variables(mc_object_info_t info) {
954 int fd = open(info->file_name, O_RDONLY);
956 xbt_die("Could not open file %s", info->file_name);
958 Dwarf *dwarf = dwarf_begin(fd, DWARF_C_READ);
960 xbt_die("Your program must be compiled with -g");
963 Dwarf_Off offset = 0;
964 Dwarf_Off next_offset = 0;
966 while (dwarf_nextcu (dwarf, offset, &next_offset, &length, NULL, NULL, NULL) == 0) {
969 if(dwarf_offdie(dwarf, offset+length, &die)!=NULL) {
971 // Skip C++ for now (we will add support for it soon):
972 int lang = dwarf_srclang(&die);
973 if((lang==DW_LANG_C_plus_plus) || (lang==DW_LANG_ObjC_plus_plus)) {
974 offset = next_offset;
978 MC_dwarf_handle_die(info, &die, &die, NULL);
980 offset = next_offset;