Files
clang-p2996/lldb/source/Plugins/Language/CPlusPlus/LibStdcppTuple.cpp
Adrian Prantl 0e4c482124 Pass ConstString by value (NFC)
My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.

ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.

(This fixes rdar://problem/48640859 for the Apple folks)

Differential Revision: https://reviews.llvm.org/D59030

llvm-svn: 355553
2019-03-06 21:22:25 +00:00

107 lines
3.1 KiB
C++

//===-- LibStdcppTuple.cpp --------------------------------------*- 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
//
//===----------------------------------------------------------------------===//
#include "LibStdcpp.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/DataFormatters/FormattersHelpers.h"
#include "lldb/DataFormatters/TypeSynthetic.h"
#include "lldb/Utility/ConstString.h"
#include <memory>
#include <vector>
using namespace lldb;
using namespace lldb_private;
using namespace lldb_private::formatters;
namespace {
class LibStdcppTupleSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
public:
explicit LibStdcppTupleSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
size_t CalculateNumChildren() override;
lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
bool Update() override;
bool MightHaveChildren() override;
size_t GetIndexOfChildWithName(ConstString name) override;
private:
std::vector<ValueObjectSP> m_members;
};
} // end of anonymous namespace
LibStdcppTupleSyntheticFrontEnd::LibStdcppTupleSyntheticFrontEnd(
lldb::ValueObjectSP valobj_sp)
: SyntheticChildrenFrontEnd(*valobj_sp) {
Update();
}
bool LibStdcppTupleSyntheticFrontEnd::Update() {
m_members.clear();
ValueObjectSP valobj_backend_sp = m_backend.GetSP();
if (!valobj_backend_sp)
return false;
ValueObjectSP next_child_sp = valobj_backend_sp->GetNonSyntheticValue();
while (next_child_sp != nullptr) {
ValueObjectSP current_child = next_child_sp;
next_child_sp = nullptr;
size_t child_count = current_child->GetNumChildren();
for (size_t i = 0; i < child_count; ++i) {
ValueObjectSP child_sp = current_child->GetChildAtIndex(i, true);
llvm::StringRef name_str = child_sp->GetName().GetStringRef();
if (name_str.startswith("std::_Tuple_impl<")) {
next_child_sp = child_sp;
} else if (name_str.startswith("std::_Head_base<")) {
ValueObjectSP value_sp =
child_sp->GetChildMemberWithName(ConstString("_M_head_impl"), true);
if (value_sp) {
StreamString name;
name.Printf("[%zd]", m_members.size());
m_members.push_back(value_sp->Clone(ConstString(name.GetString())));
}
}
}
}
return false;
}
bool LibStdcppTupleSyntheticFrontEnd::MightHaveChildren() { return true; }
lldb::ValueObjectSP
LibStdcppTupleSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
if (idx < m_members.size())
return m_members[idx];
return lldb::ValueObjectSP();
}
size_t LibStdcppTupleSyntheticFrontEnd::CalculateNumChildren() {
return m_members.size();
}
size_t LibStdcppTupleSyntheticFrontEnd::GetIndexOfChildWithName(
ConstString name) {
return ExtractIndexFromString(name.GetCString());
}
SyntheticChildrenFrontEnd *
lldb_private::formatters::LibStdcppTupleSyntheticFrontEndCreator(
CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
return (valobj_sp ? new LibStdcppTupleSyntheticFrontEnd(valobj_sp) : nullptr);
}