Files
clang-p2996/lldb/source/Plugins/SymbolFile/DWARF/DWARFIndex.h
jeffreytan81 cb04d33780 Improve namespace lookup using .debug_names parent chain (#110062)
## Summary
This PR is a continuation of
https://github.com/llvm/llvm-project/pull/108907 by using `.debug_names`
parent chain faster lookup for namespaces.


## Implementation
Similar to https://github.com/llvm/llvm-project/pull/108907. This PR
adds a new API: `GetNamespacesWithParents` in `DWARFIndex` base class.
The API performs the same function as `GetNamespaces()` with additional
filtering using parents `CompilerDeclContext`. A default implementation
is given in `DWARFIndex` class which parses debug info and performs the
matching. In the `DebugNameDWARFIndex` override, parents
`CompilerDeclContext` is cross checked with parent chain in
`.debug_names` for much faster filtering before fallback to base
implementation for final filtering.

## Performance Results
For the same benchmark used in
https://github.com/llvm/llvm-project/pull/108907, this PR improves: 48s
=> 28s

---------

Co-authored-by: jeffreytan81 <jeffreytan@fb.com>
2024-10-29 20:42:54 -07:00

146 lines
5.9 KiB
C++

//===-- DWARFIndex.h -------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFINDEX_H
#define LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFINDEX_H
#include "Plugins/SymbolFile/DWARF/DIERef.h"
#include "Plugins/SymbolFile/DWARF/DWARFDIE.h"
#include "Plugins/SymbolFile/DWARF/DWARFFormValue.h"
#include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
#include "lldb/Core/Module.h"
#include "lldb/Target/Statistics.h"
namespace lldb_private::plugin {
namespace dwarf {
class DWARFDeclContext;
class DWARFDIE;
class DWARFIndex {
public:
DWARFIndex(Module &module) : m_module(module) {}
virtual ~DWARFIndex();
virtual void Preload() = 0;
/// Finds global variables with the given base name. Any additional filtering
/// (e.g., to only retrieve variables from a given context) should be done by
/// the consumer.
virtual void
GetGlobalVariables(ConstString basename,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
virtual void
GetGlobalVariables(const RegularExpression &regex,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
/// \a cu must be the skeleton unit if possible, not GetNonSkeletonUnit().
virtual void
GetGlobalVariables(DWARFUnit &cu,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
virtual void
GetObjCMethods(ConstString class_name,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
virtual void
GetCompleteObjCClass(ConstString class_name, bool must_be_implementation,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
virtual void GetTypes(ConstString name,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
virtual void GetTypes(const DWARFDeclContext &context,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
/// Finds all DIEs whose fully qualified name matches `context`. A base
/// implementation is provided, and it uses the entire CU to check the DIE
/// parent hierarchy. Specializations should override this if they are able
/// to provide a faster implementation.
virtual void
GetFullyQualifiedType(const DWARFDeclContext &context,
llvm::function_ref<bool(DWARFDIE die)> callback);
virtual void
GetNamespaces(ConstString name,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
/// Get type DIEs meeting requires of \a query.
/// in its decl parent chain as subset. A base implementation is provided,
/// Specializations should override this if they are able to provide a faster
/// implementation.
virtual void
GetTypesWithQuery(TypeQuery &query,
llvm::function_ref<bool(DWARFDIE die)> callback);
/// Get namespace DIEs whose base name match \param name with \param
/// parent_decl_ctx in its decl parent chain. A base implementation
/// is provided. Specializations should override this if they are able to
/// provide a faster implementation.
virtual void
GetNamespacesWithParents(ConstString name,
const CompilerDeclContext &parent_decl_ctx,
llvm::function_ref<bool(DWARFDIE die)> callback);
virtual void
GetFunctions(const Module::LookupInfo &lookup_info, SymbolFileDWARF &dwarf,
const CompilerDeclContext &parent_decl_ctx,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
virtual void
GetFunctions(const RegularExpression &regex,
llvm::function_ref<bool(DWARFDIE die)> callback) = 0;
virtual void Dump(Stream &s) = 0;
StatsDuration::Duration GetIndexTime() { return m_index_time; }
protected:
Module &m_module;
StatsDuration m_index_time;
/// Helper function implementing common logic for processing function dies. If
/// the function given by "die" matches search criteria given by
/// "parent_decl_ctx" and "name_type_mask", it calls the callback with the
/// given die.
bool ProcessFunctionDIE(const Module::LookupInfo &lookup_info, DWARFDIE die,
const CompilerDeclContext &parent_decl_ctx,
llvm::function_ref<bool(DWARFDIE die)> callback);
class DIERefCallbackImpl {
public:
DIERefCallbackImpl(const DWARFIndex &index,
llvm::function_ref<bool(DWARFDIE die)> callback,
llvm::StringRef name);
bool operator()(DIERef ref) const;
bool operator()(const llvm::AppleAcceleratorTable::Entry &entry) const;
private:
const DWARFIndex &m_index;
SymbolFileDWARF &m_dwarf;
const llvm::function_ref<bool(DWARFDIE die)> m_callback;
const llvm::StringRef m_name;
};
DIERefCallbackImpl
DIERefCallback(llvm::function_ref<bool(DWARFDIE die)> callback,
llvm::StringRef name = {}) const {
return DIERefCallbackImpl(*this, callback, name);
}
void ReportInvalidDIERef(DIERef ref, llvm::StringRef name) const;
/// Implementation of `GetFullyQualifiedType` to check a single entry,
/// shareable with derived classes.
bool
GetFullyQualifiedTypeImpl(const DWARFDeclContext &context, DWARFDIE die,
llvm::function_ref<bool(DWARFDIE die)> callback);
/// Check if the type \a die can meet the requirements of \a query.
bool
ProcessTypeDIEMatchQuery(TypeQuery &query, DWARFDIE die,
llvm::function_ref<bool(DWARFDIE die)> callback);
bool ProcessNamespaceDieMatchParents(
const CompilerDeclContext &parent_decl_ctx, DWARFDIE die,
llvm::function_ref<bool(DWARFDIE die)> callback);
};
} // namespace dwarf
} // namespace lldb_private::plugin
#endif // LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFINDEX_H