[Lldb-commits] [lldb] r250821 - Make dwarf parsing multi-threaded
Tamas Berghammer via lldb-commits
lldb-commits at lists.llvm.org
Tue Oct 20 05:42:10 PDT 2015
Author: tberghammer
Date: Tue Oct 20 07:42:10 2015
New Revision: 250821
URL: http://llvm.org/viewvc/llvm-project?rev=250821&view=rev
Log:
Make dwarf parsing multi-threaded
Loading the debug info from a large application is the slowest task
LLDB do. This CL makes most of the dwarf parsing code multi-threaded.
As a result the speed of "attach; backtrace; exit;" when the inferior
is an LLDB with full debug info increased by a factor of 2 (on my machine).
Differential revision: http://reviews.llvm.org/D13662
Modified:
lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.cpp
lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.h
lldb/trunk/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
Modified: lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.cpp?rev=250821&r1=250820&r2=250821&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.cpp (original)
+++ lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.cpp Tue Oct 20 07:42:10 2015
@@ -83,3 +83,14 @@ NameToDIE::ForEach (std::function <bool(
break;
}
}
+
+void
+NameToDIE::Append (const NameToDIE& other)
+{
+ const uint32_t size = other.m_map.GetSize();
+ for (uint32_t i = 0; i < size; ++i)
+ {
+ m_map.Append(other.m_map.GetCStringAtIndexUnchecked (i),
+ other.m_map.GetValueAtIndexUnchecked (i));
+ }
+}
Modified: lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.h
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.h?rev=250821&r1=250820&r2=250821&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.h (original)
+++ lldb/trunk/source/Plugins/SymbolFile/DWARF/NameToDIE.h Tue Oct 20 07:42:10 2015
@@ -38,6 +38,9 @@ public:
Insert (const lldb_private::ConstString& name, const DIERef& die_ref);
void
+ Append (const NameToDIE& other);
+
+ void
Finalize();
size_t
Modified: lldb/trunk/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp?rev=250821&r1=250820&r2=250821&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp (original)
+++ lldb/trunk/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp Tue Oct 20 07:42:10 2015
@@ -50,6 +50,8 @@
#include "lldb/Target/Language.h"
+#include "lldb/Utility/TaskPool.h"
+
#include "DWARFASTParser.h"
#include "DWARFCompileUnit.h"
#include "DWARFDebugAbbrev.h"
@@ -2035,40 +2037,72 @@ SymbolFileDWARF::Index ()
"SymbolFileDWARF::Index (%s)",
GetObjectFile()->GetFileSpec().GetFilename().AsCString("<Unknown>"));
+
+
DWARFDebugInfo* debug_info = DebugInfo();
if (debug_info)
{
- uint32_t cu_idx = 0;
const uint32_t num_compile_units = GetNumCompileUnits();
- for (cu_idx = 0; cu_idx < num_compile_units; ++cu_idx)
+ std::vector<NameToDIE> function_basename_index(num_compile_units);
+ std::vector<NameToDIE> function_fullname_index(num_compile_units);
+ std::vector<NameToDIE> function_method_index(num_compile_units);
+ std::vector<NameToDIE> function_selector_index(num_compile_units);
+ std::vector<NameToDIE> objc_class_selectors_index(num_compile_units);
+ std::vector<NameToDIE> global_index(num_compile_units);
+ std::vector<NameToDIE> type_index(num_compile_units);
+ std::vector<NameToDIE> namespace_index(num_compile_units);
+
+ auto parser_fn = [this,
+ debug_info,
+ &function_basename_index,
+ &function_fullname_index,
+ &function_method_index,
+ &function_selector_index,
+ &objc_class_selectors_index,
+ &global_index,
+ &type_index,
+ &namespace_index](uint32_t cu_idx)
{
DWARFCompileUnit* dwarf_cu = debug_info->GetCompileUnitAtIndex(cu_idx);
+ bool clear_dies = dwarf_cu->ExtractDIEsIfNeeded(false) > 1;
- bool clear_dies = dwarf_cu->ExtractDIEsIfNeeded (false) > 1;
+ dwarf_cu->Index(function_basename_index[cu_idx],
+ function_fullname_index[cu_idx],
+ function_method_index[cu_idx],
+ function_selector_index[cu_idx],
+ objc_class_selectors_index[cu_idx],
+ global_index[cu_idx],
+ type_index[cu_idx],
+ namespace_index[cu_idx]);
- dwarf_cu->Index (m_function_basename_index,
- m_function_fullname_index,
- m_function_method_index,
- m_function_selector_index,
- m_objc_class_selectors_index,
- m_global_index,
- m_type_index,
- m_namespace_index);
-
// Keep memory down by clearing DIEs if this generate function
// caused them to be parsed
if (clear_dies)
- dwarf_cu->ClearDIEs (true);
- }
-
- m_function_basename_index.Finalize();
- m_function_fullname_index.Finalize();
- m_function_method_index.Finalize();
- m_function_selector_index.Finalize();
- m_objc_class_selectors_index.Finalize();
- m_global_index.Finalize();
- m_type_index.Finalize();
- m_namespace_index.Finalize();
+ dwarf_cu->ClearDIEs(true);
+ };
+
+ std::vector<std::future<void>> results;
+ for (uint32_t cu_idx = 0; cu_idx < num_compile_units; ++cu_idx)
+ results.emplace_back(TaskPool::AddTask(parser_fn, cu_idx));
+ for (auto& f : results)
+ f.wait();
+
+ auto merge_fn = [](NameToDIE& target, const std::vector<NameToDIE>& sources)
+ {
+ for (const auto& src : sources)
+ target.Append(src);
+ target.Finalize();
+ };
+
+ TaskPool::RunTasks(
+ [&]() { merge_fn(m_function_basename_index, function_basename_index); },
+ [&]() { merge_fn(m_function_fullname_index, function_fullname_index); },
+ [&]() { merge_fn(m_function_method_index, function_method_index); },
+ [&]() { merge_fn(m_function_selector_index, function_selector_index); },
+ [&]() { merge_fn(m_objc_class_selectors_index, objc_class_selectors_index); },
+ [&]() { merge_fn(m_global_index, global_index); },
+ [&]() { merge_fn(m_type_index, type_index); },
+ [&]() { merge_fn(m_namespace_index, namespace_index); });
#if defined (ENABLE_DEBUG_PRINTF)
StreamFile s(stdout, false);
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