-/* Copyright (c) 2008-2015. The SimGrid Team.
+/* Copyright (c) 2008-2017. The SimGrid Team.
* All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
#include <boost/algorithm/string/predicate.hpp>
-#include <simgrid_config.h>
#include "src/simgrid/util.hpp"
-#include <xbt/log.h>
-#include <xbt/sysdep.h>
+#include "xbt/log.h"
+#include "xbt/sysdep.h"
+#include <simgrid_config.h>
#include "src/mc/mc_private.h"
#include "src/mc/mc_dwarf.hpp"
-#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");
* \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.
*
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);
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)
+ if (not name)
name = MC_dwarf_attr_integrate_string(die, DW_AT_MIPS_linkage_name);
return name;
}
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)
{
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;
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
// 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",
// 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);
+ xbt_die("Can't handle form class (%d) / form 0x%x as DW_AT_member_location", (int)form_class, (unsigned)form);
}
}
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());
{
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;
}
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->id,
- 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:
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);
+ 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);
}
}
{
std::unique_ptr<simgrid::mc::Variable> 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 (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;
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;
static
std::vector<char> 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 notes and find the NT_GNU_BUILD_ID one:
size_t pos = 0;
- while (1) {
+ 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 note is identified by a name "GNU" and a integer type within
- // the namespace defined by this name (here NT_GNU_BUILD_ID):
+ // 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) {
-
- // Found the NT_GNU_BUILD_ID note:
+ 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<char>(start, end);
-
}
}
}
+#endif
return std::vector<char>();
}
* 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<char> id)
{
std::string filename;
- for (const char* debug_path : debug_paths) {
- filename = debug_path;
- filename += ".build-id/" + to_hex(id.data(), 1) + '/'
+ 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)
+ 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();
}
* 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");
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` (relocatable):
+ // 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;
}
dwarf_end(dwarf);
- // If there was no DWARF in the file, try to find it in a separate file
- // with NT_GNU_BUILD_ID:
+ // 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<char> build_id = get_build_id(elf);
- if (!build_id.empty()) {
+ if (not build_id.empty()) {
elf_end(elf);
close(fd);
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"
+ 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());
}
return;
}
- // TODO, try to find DWARF info using debug-link.
- // Is this method really used anywhere?
+ // 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());
// Someone needs this to be sorted but who?
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);
// 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)
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);
std::make_shared<simgrid::mc::ObjectInformation>();
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)
/*************************************************************************/
-void postProcessObjectInformation(simgrid::mc::Process* process, simgrid::mc::ObjectInformation* info)
+void postProcessObjectInformation(simgrid::mc::RemoteClient* process, simgrid::mc::ObjectInformation* info)
{
for (auto& i : info->types) {
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;
}
