X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/c87e7c0f5dceba55bed683048b55016a23d52388..5fd5c2b8932f9288216e47e78580d31aca2892a1:/src/mc/mc_dwarf.cpp diff --git a/src/mc/mc_dwarf.cpp b/src/mc/mc_dwarf.cpp index a3514bf2a4..ec22c9a71e 100644 --- a/src/mc/mc_dwarf.cpp +++ b/src/mc/mc_dwarf.cpp @@ -1,5 +1,4 @@ -/* Copyright (c) 2008-2015. The SimGrid Team. - * All rights reserved. */ +/* Copyright (c) 2008-2019. The SimGrid Team. All rights reserved. */ /* This program is free software; you can redistribute it and/or modify it * under the terms of the license (GNU LGPL) which comes with this package. */ @@ -7,38 +6,41 @@ #include #include -#include #include +#include +#include + +#include #include -#define DW_LANG_Objc DW_LANG_ObjC /* fix spelling error in older dwarf.h */ -#include #include -#include +#include + #include "src/simgrid/util.hpp" -#include -#include +#include "xbt/log.h" +#include "xbt/string.hpp" +#include "xbt/sysdep.h" +#include -#include "src/mc/mc_private.h" #include "src/mc/mc_dwarf.hpp" +#include "src/mc/mc_private.hpp" -#include "src/mc/mc_object_info.h" -#include "src/mc/Process.hpp" #include "src/mc/ObjectInformation.hpp" #include "src/mc/Variable.hpp" +#include "src/mc/remote/RemoteClient.hpp" XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dwarf, mc, "DWARF processing"); -/** \brief The default DW_TAG_lower_bound for a given DW_AT_language. +/** @brief The default DW_TAG_lower_bound for a given DW_AT_language. * * The default for a given language is defined in the DWARF spec. * - * \param language consant as defined by the DWARf spec + * @param language constant as defined by the DWARf spec */ static uint64_t MC_dwarf_default_lower_bound(int lang); -/** \brief Computes the the element_count of a DW_TAG_enumeration_type DIE +/** @brief Computes the the element_count of a DW_TAG_enumeration_type DIE * * This is the number of elements in a given array dimension. * @@ -46,61 +48,60 @@ static uint64_t MC_dwarf_default_lower_bound(int lang); * needed because the default lower bound (when there is no DW_AT_lower_bound) * depends of the language of the compilation unit (DW_AT_language). * - * \param die DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type - * \param unit DIE of the DW_TAG_compile_unit + * @param die DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type + * @param unit DIE of the DW_TAG_compile_unit */ -static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die * die, - Dwarf_Die * unit); +static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit); -/** \brief Computes the number of elements of a given DW_TAG_array_type. +/** @brief Computes the number of elements of a given DW_TAG_array_type. * - * \param die DIE for the DW_TAG_array_type + * @param die DIE for the DW_TAG_array_type */ static uint64_t MC_dwarf_array_element_count(Dwarf_Die * die, Dwarf_Die * unit); -/** \brief Process a DIE +/** @brief Process a DIE * - * \param info the resulting object fot the library/binary file (output) - * \param die the current DIE - * \param unit the DIE of the compile unit of the current DIE - * \param frame containg frame if any + * @param info the resulting object fot the library/binary file (output) + * @param die the current DIE + * @param unit the DIE of the compile unit of the current DIE + * @param frame containing frame if any */ static void MC_dwarf_handle_die(simgrid::mc::ObjectInformation* info, Dwarf_Die * die, Dwarf_Die * unit, simgrid::mc::Frame* frame, const char *ns); -/** \brief Process a type DIE +/** @brief Process a type DIE */ static void MC_dwarf_handle_type_die(simgrid::mc::ObjectInformation* info, Dwarf_Die * die, Dwarf_Die * unit, simgrid::mc::Frame* frame, const char *ns); -/** \brief Calls MC_dwarf_handle_die on all childrend of the given die +/** @brief Calls MC_dwarf_handle_die on all children of the given die * - * \param info the resulting object fot the library/binary file (output) - * \param die the current DIE - * \param unit the DIE of the compile unit of the current DIE - * \param frame containg frame if any + * @param info the resulting object fot the library/binary file (output) + * @param die the current DIE + * @param unit the DIE of the compile unit of the current DIE + * @param frame containing frame if any */ static void MC_dwarf_handle_children(simgrid::mc::ObjectInformation* info, Dwarf_Die * die, Dwarf_Die * unit, simgrid::mc::Frame* frame, const char *ns); -/** \brief Handle a variable (DW_TAG_variable or other) +/** @brief Handle a variable (DW_TAG_variable or other) * - * \param info the resulting object fot the library/binary file (output) - * \param die the current DIE - * \param unit the DIE of the compile unit of the current DIE - * \param frame containg frame if any + * @param info the resulting object fot the library/binary file (output) + * @param die the current DIE + * @param unit the DIE of the compile unit of the current DIE + * @param frame containing frame if any */ static void MC_dwarf_handle_variable_die(simgrid::mc::ObjectInformation* info, Dwarf_Die * die, Dwarf_Die * unit, simgrid::mc::Frame* frame, const char *ns); -/** \brief Get the DW_TAG_type of the DIE +/** @brief Get the DW_TAG_type of the DIE * - * \param die DIE - * \return DW_TAG_type attribute as a new string (nullptr if none) + * @param die DIE + * @return DW_TAG_type attribute as a new string (nullptr if none) */ static std::uint64_t MC_dwarf_at_type(Dwarf_Die * die); @@ -184,12 +185,12 @@ TagClass classify_tag(int tag) } } -/** \brief Find the DWARF data class for a given DWARF data form +/** @brief Find the DWARF data class for a given DWARF data form * * This mapping is defined in the DWARF spec. * - * \param form The form (values taken from the DWARF spec) - * \return An internal representation for the corresponding class + * @param form The form (values taken from the DWARF spec) + * @return An internal representation for the corresponding class * */ static FormClass classify_form(int form) @@ -231,10 +232,10 @@ FormClass classify_form(int form) } } -/** \brief Get the name of the tag of a given DIE +/** @brief Get the name of the tag of a given DIE * - * \param die DIE - * \return name of the tag of this DIE + * @param die DIE + * @return name of the tag of this DIE */ inline XBT_PRIVATE const char *tagname(Dwarf_Die * die) @@ -247,40 +248,22 @@ const char *tagname(Dwarf_Die * die) // ***** Attributes -/** \brief Get an attribute of a given DIE as a string +/** @brief Get an attribute of a given DIE as a string * - * \param die the DIE - * \param attribute attribute - * \return value of the given attribute of the given DIE + * @param die the DIE + * @param attribute attribute + * @return value of the given attribute of the given DIE */ static const char *MC_dwarf_attr_integrate_string(Dwarf_Die * die, int attribute) { Dwarf_Attribute attr; - if (!dwarf_attr_integrate(die, attribute, &attr)) + if (not dwarf_attr_integrate(die, attribute, &attr)) return nullptr; else return dwarf_formstring(&attr); } -/** \brief Get the linkage name of a DIE. - * - * Use either DW_AT_linkage_name or DW_AT_MIPS_linkage_name. - * DW_AT_linkage_name is standardized since DWARF 4. - * Before this version of DWARF, the MIPS extensions - * DW_AT_MIPS_linkage_name is used (at least by GCC). - * - * \param the DIE - * \return linkage name of the given DIE (or nullptr) - * */ -static const char *MC_dwarf_at_linkage_name(Dwarf_Die * die) -{ - const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_linkage_name); - if (!name) - name = MC_dwarf_attr_integrate_string(die, DW_AT_MIPS_linkage_name); - return name; -} - static Dwarf_Off MC_dwarf_attr_dieoffset(Dwarf_Die * die, int attribute) { Dwarf_Attribute attr; @@ -306,10 +289,10 @@ static Dwarf_Off MC_dwarf_attr_integrate_dieoffset(Dwarf_Die * die, return dwarf_dieoffset(&subtype_die); } -/** \brief Find the type/subtype (DW_AT_type) for a DIE +/** @brief Find the type/subtype (DW_AT_type) for a DIE * - * \param dit the DIE - * \return DW_AT_type reference as a global offset in hexadecimal (or nullptr) + * @param die the DIE + * @return DW_AT_type reference as a global offset in hexadecimal (or nullptr) */ static std::uint64_t MC_dwarf_at_type(Dwarf_Die * die) @@ -354,13 +337,13 @@ static bool MC_dwarf_attr_flag(Dwarf_Die * die, int attribute, bool integrate) return result; } -/** \brief Find the default lower bound for a given language +/** @brief Find the default lower bound for a given language * * The default lower bound of an array (when DW_TAG_lower_bound * is missing) depends on the language of the compilation unit. * - * \param lang Language of the compilation unit (values defined in the DWARF spec) - * \return Default lower bound of an array in this compilation unit + * @param lang Language of the compilation unit (values defined in the DWARF spec) + * @return Default lower bound of an array in this compilation unit * */ static uint64_t MC_dwarf_default_lower_bound(int lang) { @@ -394,11 +377,11 @@ static uint64_t MC_dwarf_default_lower_bound(int lang) } } -/** \brief Finds the number of elements in a DW_TAG_subrange_type or DW_TAG_enumeration_type DIE +/** @brief Finds the number of elements in a DW_TAG_subrange_type or DW_TAG_enumeration_type DIE * - * \param die the DIE - * \param unit DIE of the compilation unit - * \return number of elements in the range + * @param die the DIE + * @param unit DIE of the compilation unit + * @return number of elements in the range * */ static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die * die, Dwarf_Die * unit) @@ -413,29 +396,28 @@ static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die * die, return MC_dwarf_attr_integrate_uint(die, DW_AT_count, 0); // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound + 1: - if (!dwarf_hasattr_integrate(die, DW_AT_upper_bound)) + if (not dwarf_hasattr_integrate(die, DW_AT_upper_bound)) // This is not really 0, but the code expects this (we do not know): return 0; - uint64_t upper_bound = - MC_dwarf_attr_integrate_uint(die, DW_AT_upper_bound, -1); + uint64_t upper_bound = MC_dwarf_attr_integrate_uint(die, DW_AT_upper_bound, static_cast(-1)); uint64_t lower_bound = 0; if (dwarf_hasattr_integrate(die, DW_AT_lower_bound)) - lower_bound = MC_dwarf_attr_integrate_uint(die, DW_AT_lower_bound, -1); + lower_bound = MC_dwarf_attr_integrate_uint(die, DW_AT_lower_bound, static_cast(-1)); else lower_bound = MC_dwarf_default_lower_bound(dwarf_srclang(unit)); return upper_bound - lower_bound + 1; } -/** \brief Finds the number of elements in a array type (DW_TAG_array_type) +/** @brief Finds the number of elements in a array type (DW_TAG_array_type) * * The compilation unit might be needed because the default lower * bound depends on the language of the compilation unit. * - * \param die the DIE of the DW_TAG_array_type - * \param unit the DIE of the compilation unit - * \return number of elements in this array type + * @param die the DIE of the DW_TAG_array_type + * @param unit the DIE of the compilation unit + * @return number of elements in this array type * */ static uint64_t MC_dwarf_array_element_count(Dwarf_Die * die, Dwarf_Die * unit) { @@ -465,7 +447,7 @@ static uint64_t MC_dwarf_array_element_count(Dwarf_Die * die, Dwarf_Die * unit) static bool MC_compare_variable( simgrid::mc::Variable const& a, simgrid::mc::Variable const& b) { - int cmp = strcmp(a.name.c_str(), b.name.c_str()); + int cmp = a.name.compare(b.name); if (cmp < 0) return true; else if (cmp > 0) @@ -476,12 +458,12 @@ static bool MC_compare_variable( // ***** simgrid::mc::Type* -/** \brief Initialize the location of a member of a type +/** @brief Initialize the location of a member of a type * (DW_AT_data_member_location of a DW_TAG_member). * - * \param type a type (struct, class) - * \param member the member of the type - * \param child DIE of the member (DW_TAG_member) + * @param type a type (struct, class) + * @param member the member of the type + * @param child DIE of the member (DW_TAG_member) */ static void MC_dwarf_fill_member_location( simgrid::mc::Type* type, simgrid::mc::Member* member, Dwarf_Die * child) @@ -489,7 +471,7 @@ static void MC_dwarf_fill_member_location( if (dwarf_hasattr(child, DW_AT_data_bit_offset)) xbt_die("Can't groke DW_AT_data_bit_offset."); - if (!dwarf_hasattr_integrate(child, DW_AT_data_member_location)) { + if (not dwarf_hasattr_integrate(child, DW_AT_data_member_location)) { if (type->type == DW_TAG_union_type) return; xbt_die @@ -521,7 +503,7 @@ static void MC_dwarf_fill_member_location( // Offset from the base address of the object: { Dwarf_Word offset; - if (!dwarf_formudata(&attr, &offset)) + if (not dwarf_formudata(&attr, &offset)) member->offset(offset); else xbt_die("Cannot get %s location <%" PRIx64 ">%s", @@ -529,28 +511,24 @@ static void MC_dwarf_fill_member_location( (uint64_t) type->id, type->name.c_str()); break; } - case simgrid::dwarf::FormClass::LocListPtr: - // Reference to a location list: - // TODO - case simgrid::dwarf::FormClass::Reference: - // It's supposed to be possible in DWARF2 but I couldn't find its semantic - // in the spec. + default: - xbt_die("Can't handle form class (%i) / form 0x%x as DW_AT_member_location", - (int) form_class, form); + // includes FormClass::LocListPtr (reference to a location list: TODO) and FormClass::Reference (it's supposed to be + // possible in DWARF2 but I couldn't find its semantic in the spec) + xbt_die("Can't handle form class (%d) / form 0x%x as DW_AT_member_location", (int)form_class, (unsigned)form); } } -/** \brief Populate the list of members of a type +/** @brief Populate the list of members of a type * - * \param info ELF object containing the type DIE - * \param die DIE of the type - * \param unit DIE of the compilation unit containing the type DIE - * \param type the type + * @param info ELF object containing the type DIE + * @param die DIE of the type + * @param unit DIE of the compilation unit containing the type DIE + * @param type the type */ -static void MC_dwarf_add_members(simgrid::mc::ObjectInformation* info, Dwarf_Die * die, - Dwarf_Die * unit, simgrid::mc::Type* type) +static void MC_dwarf_add_members(simgrid::mc::ObjectInformation* /*info*/, Dwarf_Die* die, Dwarf_Die* /*unit*/, + simgrid::mc::Type* type) { int res; Dwarf_Die child; @@ -570,11 +548,35 @@ static void MC_dwarf_add_members(simgrid::mc::ObjectInformation* info, Dwarf_Die // TODO, we should use another type (because is is not a type but a member) simgrid::mc::Member member; - member.inheritance = tag == DW_TAG_inheritance; + if (tag == DW_TAG_inheritance) + member.flags |= simgrid::mc::Member::INHERITANCE_FLAG; const char *name = MC_dwarf_attr_integrate_string(&child, DW_AT_name); if (name) member.name = name; + // Those base names are used by GCC and clang for virtual table pointers + // respectively ("__vptr$ClassName", "__vptr.ClassName"): + if (boost::algorithm::starts_with(member.name, "__vptr$") || + boost::algorithm::starts_with(member.name, "__vptr.")) + member.flags |= simgrid::mc::Member::VIRTUAL_POINTER_FLAG; + // A cleaner solution would be to check against the type: + // --- + // tag: DW_TAG_member + // name: "_vptr$Foo" + // type: + // # Type for a pointer to a vtable + // tag: DW_TAG_pointer_type + // type: + // # Type for a vtable: + // tag: DW_TAG_pointer_type + // name: "__vtbl_ptr_type" + // type: + // tag: DW_TAG_subroutine_type + // type: + // tag: DW_TAG_base_type + // name: "int" + // --- + member.byte_size = MC_dwarf_attr_integrate_uint(&child, DW_AT_byte_size, 0); member.type_id = MC_dwarf_at_type(&child); @@ -584,7 +586,7 @@ static void MC_dwarf_add_members(simgrid::mc::ObjectInformation* info, Dwarf_Die MC_dwarf_fill_member_location(type, &member, &child); - if (!member.type_id) + if (not member.type_id) xbt_die("Missing type for member %s of <%" PRIx64 ">%s", member.name.c_str(), (uint64_t) type->id, type->name.c_str()); @@ -594,12 +596,12 @@ static void MC_dwarf_add_members(simgrid::mc::ObjectInformation* info, Dwarf_Die } } -/** \brief Create a MC type object from a DIE +/** @brief Create a MC type object from a DIE * - * \param info current object info object - * \param DIE (for a given type); - * \param unit compilation unit of the current DIE - * \return MC representation of the type + * @param info current object info object + * @param die DIE (for a given type) + * @param unit compilation unit of the current DIE + * @return MC representation of the type */ static simgrid::mc::Type MC_dwarf_die_to_type( simgrid::mc::ObjectInformation* info, Dwarf_Die * die, @@ -631,10 +633,10 @@ static simgrid::mc::Type MC_dwarf_die_to_type( const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name); if (name != nullptr) { - char* full_name = ns ? bprintf("%s%s::%s", prefix, ns, name) : - bprintf("%s%s", prefix, name); - type.name = std::string(full_name); - free(full_name); + if (ns) + type.name = simgrid::xbt::string_printf("%s%s::%s", prefix, ns, name); + else + type.name = simgrid::xbt::string_printf("%s%s", prefix, name); } type.type_id = MC_dwarf_at_type(die); @@ -645,7 +647,7 @@ static simgrid::mc::Type MC_dwarf_die_to_type( if (type.type == DW_TAG_pointer_type) type.byte_size = sizeof(void*); - // Computation of the byte_size; + // Computation of the byte_size if (dwarf_hasattr_integrate(die, DW_AT_byte_size)) type.byte_size = MC_dwarf_attr_integrate_uint(die, DW_AT_byte_size, 0); else if (type.type == DW_TAG_array_type @@ -671,14 +673,16 @@ static simgrid::mc::Type MC_dwarf_die_to_type( case DW_TAG_union_type: case DW_TAG_class_type: MC_dwarf_add_members(info, die, unit, &type); - char *new_ns = ns == nullptr ? xbt_strdup(type.name.c_str()) - : bprintf("%s::%s", ns, name); - MC_dwarf_handle_children(info, die, unit, frame, new_ns); - free(new_ns); + MC_dwarf_handle_children(info, die, unit, frame, + ns ? simgrid::xbt::string_printf("%s::%s", ns, name).c_str() : type.name.c_str()); + break; + + default: + XBT_DEBUG("Unhandled type: %d (%s)", type.type, simgrid::dwarf::tagname(type.type)); break; } - return std::move(type); + return type; } static void MC_dwarf_handle_type_die(simgrid::mc::ObjectInformation* info, Dwarf_Die * die, @@ -687,16 +691,15 @@ static void MC_dwarf_handle_type_die(simgrid::mc::ObjectInformation* info, Dwarf { simgrid::mc::Type type = MC_dwarf_die_to_type(info, die, unit, frame, ns); auto& t = (info->types[type.id] = std::move(type)); - if (!t.name.empty() && type.byte_size != 0) + if (not t.name.empty() && type.byte_size != 0) info->full_types_by_name[t.name] = &t; } static int mc_anonymous_variable_index = 0; -static std::unique_ptr MC_die_to_variable( - simgrid::mc::ObjectInformation* info, Dwarf_Die * die, - Dwarf_Die * unit, simgrid::mc::Frame* frame, - const char *ns) +static std::unique_ptr MC_die_to_variable(simgrid::mc::ObjectInformation* info, Dwarf_Die* die, + Dwarf_Die* /*unit*/, simgrid::mc::Frame* frame, + const char* ns) { // Skip declarations: if (MC_dwarf_attr_flag(die, DW_AT_declaration, false)) @@ -713,7 +716,7 @@ static std::unique_ptr MC_die_to_variable( std::unique_ptr variable = std::unique_ptr(new simgrid::mc::Variable()); - variable->dwarf_offset = dwarf_dieoffset(die); + variable->id = dwarf_dieoffset(die); variable->global = frame == nullptr; // Can be override base on DW_AT_location variable->object_info = info; @@ -739,18 +742,18 @@ static std::unique_ptr MC_die_to_variable( xbt_die( "Could not read location expression in DW_AT_location " "of variable <%" PRIx64 ">%s", - (uint64_t) variable->dwarf_offset, + (uint64_t) variable->id, variable->name.c_str()); } if (len == 1 && expr[0].atom == DW_OP_addr) { - variable->global = 1; + variable->global = true; uintptr_t offset = (uintptr_t) expr[0].number; uintptr_t base = (uintptr_t) info->base_address(); variable->address = (void *) (base + offset); } else variable->location_list = { - simgrid::dwarf::DwarfExpression(expr, expr + len) }; + simgrid::dwarf::LocationListEntry(simgrid::dwarf::DwarfExpression(expr, expr + len))}; break; } @@ -763,33 +766,23 @@ static std::unique_ptr MC_die_to_variable( break; default: - xbt_die("Unexpected form 0x%x (%i), class 0x%x (%i) list for location " - "in <%" PRIx64 ">%s", - form, form, (int) form_class, (int) form_class, - (uint64_t) variable->dwarf_offset, - variable->name.c_str()); + xbt_die("Unexpected form 0x%x (%i), class 0x%x (%i) list for location in <%" PRIx64 ">%s", (unsigned)form, form, + (unsigned)form_class, (int)form_class, (uint64_t)variable->id, variable->name.c_str()); } // Handle start_scope: if (dwarf_hasattr(die, DW_AT_start_scope)) { Dwarf_Attribute attr; dwarf_attr(die, DW_AT_start_scope, &attr); - int form = dwarf_whatform(&attr); - simgrid::dwarf::FormClass form_class = simgrid::dwarf::classify_form(form); - switch (form_class) { - case simgrid::dwarf::FormClass::Constant: - { - Dwarf_Word value; - variable->start_scope = - dwarf_formudata(&attr, &value) == 0 ? (size_t) value : 0; - break; - } - - case simgrid::dwarf::FormClass::RangeListPtr: // TODO - default: - xbt_die - ("Unhandled form 0x%x, class 0x%X for DW_AT_start_scope of variable %s", - form, (int) form_class, name == nullptr ? "?" : name); + form = dwarf_whatform(&attr); + form_class = simgrid::dwarf::classify_form(form); + if (form_class == simgrid::dwarf::FormClass::Constant) { + Dwarf_Word value; + variable->start_scope = dwarf_formudata(&attr, &value) == 0 ? (size_t)value : 0; + } else { + // TODO: FormClass::RangeListPtr + xbt_die("Unhandled form 0x%x, class 0x%X for DW_AT_start_scope of variable %s", (unsigned)form, + (unsigned)form_class, name == nullptr ? "?" : name); } } @@ -799,11 +792,11 @@ static std::unique_ptr MC_die_to_variable( // The current code needs a variable name, // generate a fake one: - if (variable->name.empty()) - variable->name = - "@anonymous#" + std::to_string(mc_anonymous_variable_index++); - - return std::move(variable); + if (variable->name.empty()) { + variable->name = "@anonymous#" + std::to_string(mc_anonymous_variable_index); + mc_anonymous_variable_index++; + } + return variable; } static void MC_dwarf_handle_variable_die(simgrid::mc::ObjectInformation* info, Dwarf_Die * die, @@ -812,10 +805,10 @@ static void MC_dwarf_handle_variable_die(simgrid::mc::ObjectInformation* info, D { std::unique_ptr variable = MC_die_to_variable(info, die, unit, frame, ns); - if (!variable) + if (not variable) return; // Those arrays are sorted later: - else if (variable->global) + if (variable->global) info->global_variables.push_back(std::move(*variable)); else if (frame != nullptr) frame->variables.push_back(std::move(*variable)); @@ -846,7 +839,7 @@ static void MC_dwarf_handle_scope_die(simgrid::mc::ObjectInformation* info, Dwar if (klass == simgrid::dwarf::TagClass::Subprogram) { const char *name = MC_dwarf_attr_integrate_string(die, DW_AT_name); - if (ns) + if (name && ns) frame.name = std::string(ns) + "::" + name; else if (name) frame.name = name; @@ -866,7 +859,7 @@ static void MC_dwarf_handle_scope_die(simgrid::mc::ObjectInformation* info, Dwar if (low_pc) { // DW_AT_high_pc: Dwarf_Attribute attr; - if (!dwarf_attr_integrate(die, DW_AT_high_pc, &attr)) + if (not dwarf_attr_integrate(die, DW_AT_high_pc, &attr)) xbt_die("Missing DW_AT_high_pc matching with DW_AT_low_pc"); Dwarf_Sword offset; @@ -886,7 +879,7 @@ static void MC_dwarf_handle_scope_die(simgrid::mc::ObjectInformation* info, Dwar case simgrid::dwarf::FormClass::Address: if (dwarf_formaddr(&attr, &high_pc) != 0) xbt_die("Could not read address"); - frame.range.begin() = base + high_pc; + frame.range.end() = base + high_pc; break; default: @@ -907,8 +900,7 @@ static void MC_dwarf_handle_scope_die(simgrid::mc::ObjectInformation* info, Dwar // We sort them in order to have an (somewhat) efficient by name // lookup: - std::sort(frame.variables.begin(), frame.variables.end(), - MC_compare_variable); + boost::range::sort(frame.variables, MC_compare_variable); // Register it: if (klass == simgrid::dwarf::TagClass::Subprogram) @@ -997,70 +989,225 @@ void read_dwarf_info(simgrid::mc::ObjectInformation* info, Dwarf* dwarf) Dwarf_Off next_offset = 0; size_t length; - while (dwarf_nextcu(dwarf, offset, &next_offset, &length, nullptr, NULL, NULL) == + while (dwarf_nextcu(dwarf, offset, &next_offset, &length, nullptr, nullptr, nullptr) == 0) { Dwarf_Die unit_die; if (dwarf_offdie(dwarf, offset + length, &unit_die) != nullptr) - MC_dwarf_handle_children(info, &unit_die, &unit_die, nullptr, NULL); + MC_dwarf_handle_children(info, &unit_die, &unit_die, nullptr, nullptr); offset = next_offset; } } -/** \brief Populate the debugging informations of the given ELF object +/** Get the build-id (NT_GNU_BUILD_ID) from the ELF file + * + * This build-id may is used to locate an external debug (DWARF) file + * for this ELF file. + * + * @param elf libelf handle for an ELF file + * @return build-id for this ELF file (or an empty vector if none is found) + */ +static +std::vector get_build_id(Elf* elf) +{ +#ifdef __linux + // Summary: the GNU build ID is stored in a ("GNU, NT_GNU_BUILD_ID) note + // found in a PT_NOTE entry in the program header table. + + size_t phnum; + if (elf_getphdrnum (elf, &phnum) != 0) + xbt_die("Could not read program headers"); + + // Iterate over the program headers and find the PT_NOTE ones: + for (size_t i = 0; i < phnum; ++i) { + GElf_Phdr phdr_temp; + GElf_Phdr *phdr = gelf_getphdr(elf, i, &phdr_temp); + if (phdr->p_type != PT_NOTE) + continue; + + Elf_Data* data = elf_getdata_rawchunk(elf, phdr->p_offset, phdr->p_filesz, ELF_T_NHDR); + + // Iterate over the notes and find the NT_GNU_BUILD_ID one: + size_t pos = 0; + while (pos < data->d_size) { + GElf_Nhdr nhdr; + // Location of the name within Elf_Data: + size_t name_pos; + size_t desc_pos; + pos = gelf_getnote(data, pos, &nhdr, &name_pos, &desc_pos); + // A build ID note is identified by the pair ("GNU", NT_GNU_BUILD_ID) + // (a namespace and a type within this namespace): + if (nhdr.n_type == NT_GNU_BUILD_ID + && nhdr.n_namesz == sizeof("GNU") + && memcmp((char*) data->d_buf + name_pos, "GNU", sizeof("GNU")) == 0) { + XBT_DEBUG("Found GNU/NT_GNU_BUILD_ID note"); + char* start = (char*) data->d_buf + desc_pos; + char* end = (char*) start + nhdr.n_descsz; + return std::vector(start, end); + } + } + + } +#endif + return std::vector(); +} + +static char hexdigits[16] = { + '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', + 'a', 'b', 'c', 'd', 'e', 'f' +}; + +/** Binary data to hexadecimal */ +static inline +std::array to_hex(std::uint8_t byte) +{ + // Horrid double braces! + // Apparently, this is needed in C++11 (not in C++14). + return { { hexdigits[byte >> 4], hexdigits[byte & 0xF] } }; +} + +/** Binary data to hexadecimal */ +static +std::string to_hex(const char* data, std::size_t count) +{ + std::string res; + res.resize(2*count); + for (std::size_t i = 0; i < count; i++) { + std::array hex_byte = to_hex(data[i]); + for (int j = 0; j < 2; ++j) + res[2 * i + j] = hex_byte[j]; + } + return res; +} + +/** Binary data to hexadecimal */ +static +std::string to_hex(std::vector const& data) +{ + return to_hex(data.data(), data.size()); +} + +/** Base directories for external debug files */ +static +const char* debug_paths[] = { + "/usr/lib/debug/", + "/usr/local/lib/debug/", +}; + +/** Locate an external debug file from the NT_GNU_BUILD_ID + * + * This is one of the mechanisms used for + * [separate debug files](https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html). + */ +// Example: +// /usr/lib/debug/.build-id/0b/dc77f1c29aea2b14ff5acd9a19ab3175ffdeae.debug +static +std::string find_by_build_id(std::vector id) +{ + std::string filename; + std::string hex = to_hex(id); + for (const char* const& debug_path : debug_paths) { + // Example: + filename = std::string(debug_path) + ".build-id/" + + to_hex(id.data(), 1) + '/' + + to_hex(id.data() + 1, id.size() - 1) + ".debug"; + XBT_DEBUG("Checking debug file: %s", filename.c_str()); + if (access(filename.c_str(), F_OK) == 0) { + XBT_DEBUG("Found debug file: %s\n", hex.c_str()); + return filename; + } + } + XBT_DEBUG("Not debuf info found for build ID %s\n", hex.data()); + return std::string(); +} + +/** @brief Populate the debugging informations of the given ELF object * * Read the DWARf information of the EFFL object and populate the * lists of types, variables, functions. */ static -void MC_dwarf_get_variables(simgrid::mc::ObjectInformation* info) +void MC_load_dwarf(simgrid::mc::ObjectInformation* info) { if (elf_version(EV_CURRENT) == EV_NONE) xbt_die("libelf initialization error"); + // Open the ELF file: int fd = open(info->file_name.c_str(), O_RDONLY); if (fd < 0) xbt_die("Could not open file %s", info->file_name.c_str()); Elf* elf = elf_begin(fd, ELF_C_READ, nullptr); if (elf == nullptr) - xbt_die("Not an ELF file 1"); + xbt_die("Not an ELF file"); Elf_Kind kind = elf_kind(elf); if (kind != ELF_K_ELF) - xbt_die("Not an ELF file 2"); + xbt_die("Not an ELF file"); + // Remember if this is a `ET_EXEC` (fixed location) or `ET_DYN`: Elf64_Half type = get_type(elf); if (type == ET_EXEC) info->flags |= simgrid::mc::ObjectInformation::Executable; + // Read DWARF debug information in the file: Dwarf* dwarf = dwarf_begin_elf (elf, DWARF_C_READ, nullptr); - // Dwarf *dwarf = dwarf_begin(fd, DWARF_C_READ); if (dwarf != nullptr) { read_dwarf_info(info, dwarf); dwarf_end(dwarf); - dwarf = nullptr; + elf_end(elf); + close(fd); + return; + } + dwarf_end(dwarf); + + // If there was no DWARF in the file, try to find it in a separate file. + // Different methods might be used to store the DWARF informations: + // * GNU NT_GNU_BUILD_ID + // * .gnu_debuglink + // See https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html + // for reference of what we are doing. + + // Try with NT_GNU_BUILD_ID: we find the build ID in the ELF file and then + // use this ID to find the file in some known locations in the filesystem. + std::vector build_id = get_build_id(elf); + if (not build_id.empty()) { + elf_end(elf); + close(fd); + + // Find the debug file using the build id: + std::string debug_file = find_by_build_id(build_id); + if (debug_file.empty()) { + std::string hex = to_hex(build_id); + xbt_die("Missing debug info for %s with build-id %s\n" + "You might want to install the suitable debugging package.\n", + info->file_name.c_str(), hex.c_str()); + } + + // Load the DWARF info from this file: + XBT_DEBUG("Load DWARF for %s from %s", + info->file_name.c_str(), debug_file.c_str()); + fd = open(debug_file.c_str(), O_RDONLY); + if (fd < 0) + xbt_die("Could not open file %s", debug_file.c_str()); + dwarf = dwarf_begin(fd, DWARF_C_READ); + if (dwarf == nullptr) + xbt_die("No DWARF info in %s for %s", + debug_file.c_str(), info->file_name.c_str()); + read_dwarf_info(info, dwarf); + dwarf_end(dwarf); + close(fd); + return; } - else - xbt_die("Missing debugging information in %s\n" - "Your program and its dependencies must have debugging information.\n" - "You might want to recompile with -g or install the suitable debugging package.\n", - info->file_name.c_str()); + + // TODO, try to find DWARF info using .gnu_debuglink. elf_end(elf); close(fd); + xbt_die("Debugging information not found for %s\n" + "Try recompiling with -g\n", + info->file_name.c_str()); } // ***** Functions index -static int MC_compare_frame_index_items(simgrid::mc::FunctionIndexEntry* a, - simgrid::mc::FunctionIndexEntry* b) -{ - if (a->low_pc < b->low_pc) - return -1; - else if (a->low_pc == b->low_pc) - return 0; - else - return 1; -} - static void MC_make_functions_index(simgrid::mc::ObjectInformation* info) { info->functions_index.clear(); @@ -1077,7 +1224,7 @@ static void MC_make_functions_index(simgrid::mc::ObjectInformation* info) info->functions_index.shrink_to_fit(); // Sort the array by low_pc: - std::sort(info->functions_index.begin(), info->functions_index.end(), + boost::range::sort(info->functions_index, [](simgrid::mc::FunctionIndexEntry const& a, simgrid::mc::FunctionIndexEntry const& b) { @@ -1088,10 +1235,9 @@ static void MC_make_functions_index(simgrid::mc::ObjectInformation* info) static void MC_post_process_variables(simgrid::mc::ObjectInformation* info) { // Someone needs this to be sorted but who? - std::sort(info->global_variables.begin(), info->global_variables.end(), - MC_compare_variable); + boost::range::sort(info->global_variables, MC_compare_variable); - for(simgrid::mc::Variable& variable : info->global_variables) + for (simgrid::mc::Variable& variable : info->global_variables) if (variable.type_id) variable.type = simgrid::util::find_map_ptr( info->types, variable.type_id); @@ -1117,15 +1263,14 @@ static void mc_post_process_scope(simgrid::mc::ObjectInformation* info, simgrid: // Recursive post-processing of nested-scopes: for (simgrid::mc::Frame& nested_scope : scope->scopes) - mc_post_process_scope(info, &nested_scope); - + mc_post_process_scope(info, &nested_scope); } static simgrid::mc::Type* MC_resolve_type( simgrid::mc::ObjectInformation* info, unsigned type_id) { - if (!type_id) + if (not type_id) return nullptr; simgrid::mc::Type* type = simgrid::util::find_map_ptr(info->types, type_id); if (type == nullptr) @@ -1151,37 +1296,40 @@ simgrid::mc::Type* MC_resolve_type( static void MC_post_process_types(simgrid::mc::ObjectInformation* info) { // Lookup "subtype" field: - for(auto& i : info->types) { + for (auto& i : info->types) { i.second.subtype = MC_resolve_type(info, i.second.type_id); for (simgrid::mc::Member& member : i.second.members) member.type = MC_resolve_type(info, member.type_id); } } -/** \brief Finds informations about a given shared object/executable */ -std::shared_ptr MC_find_object_info( +namespace simgrid { +namespace mc { + +/** @brief Finds informations about a given shared object/executable */ +std::shared_ptr createObjectInformation( std::vector const& maps, const char *name) { std::shared_ptr result = std::make_shared(); result->file_name = name; simgrid::mc::find_object_address(maps, result.get()); - MC_dwarf_get_variables(result.get()); + MC_load_dwarf(result.get()); MC_post_process_variables(result.get()); MC_post_process_types(result.get()); for (auto& entry : result.get()->subprograms) mc_post_process_scope(result.get(), &entry.second); MC_make_functions_index(result.get()); - return std::move(result); + return result; } /*************************************************************************/ -void MC_post_process_object_info(simgrid::mc::Process* process, simgrid::mc::ObjectInformation* info) +void postProcessObjectInformation(simgrid::mc::RemoteClient* process, simgrid::mc::ObjectInformation* info) { - for (auto& i : info->types) { + for (auto& t : info->types) { - simgrid::mc::Type* type = &(i.second); + simgrid::mc::Type* type = &(t.second); simgrid::mc::Type* subtype = type; while (subtype->type == DW_TAG_typedef || subtype->type == DW_TAG_volatile_type @@ -1192,11 +1340,10 @@ void MC_post_process_object_info(simgrid::mc::Process* process, simgrid::mc::Obj break; // Resolve full_type: - if (!subtype->name.empty() && subtype->byte_size == 0) + if (not subtype->name.empty() && subtype->byte_size == 0) for (auto const& object_info : process->object_infos) { auto i = object_info->full_types_by_name.find(subtype->name); - if (i != object_info->full_types_by_name.end() - && !i->second->name.empty() && i->second->byte_size) { + if (i != object_info->full_types_by_name.end() && not i->second->name.empty() && i->second->byte_size) { type->full_type = i->second; break; } @@ -1206,6 +1353,9 @@ void MC_post_process_object_info(simgrid::mc::Process* process, simgrid::mc::Obj } } +} +} + namespace simgrid { namespace dwarf { @@ -1213,7 +1363,7 @@ namespace dwarf { * * DWARF and libunwind does not use the same convention for numbering the * registers on some architectures. The function makes the necessary - * convertion. + * conversion. */ int dwarf_register_to_libunwind(int dwarf_register) { @@ -1221,7 +1371,7 @@ int dwarf_register_to_libunwind(int dwarf_register) // It seems for this arch, DWARF and libunwind agree in the numbering: return dwarf_register; #elif defined(__i386__) - // Could't find the authoritative source of information for this. + // Couldn't find the authoritative source of information for this. // This is inspired from http://source.winehq.org/source/dlls/dbghelp/cpu_i386.c#L517. switch (dwarf_register) { case 0: