106 lines · cpp
1//===-- MsvcStlTuple.cpp --------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "MsvcStl.h"10#include "lldb/DataFormatters/FormattersHelpers.h"11 12using namespace lldb;13using namespace lldb_private;14 15namespace {16 17class TupleFrontEnd : public SyntheticChildrenFrontEnd {18public:19 TupleFrontEnd(ValueObject &valobj) : SyntheticChildrenFrontEnd(valobj) {20 Update();21 }22 23 llvm::Expected<size_t> GetIndexOfChildWithName(ConstString name) override {24 auto optional_idx = formatters::ExtractIndexFromString(name.GetCString());25 if (!optional_idx) {26 return llvm::createStringError("Type has no child named '%s'",27 name.AsCString());28 }29 return *optional_idx;30 }31 32 lldb::ChildCacheState Update() override;33 llvm::Expected<uint32_t> CalculateNumChildren() override {34 return m_elements.size();35 }36 ValueObjectSP GetChildAtIndex(uint32_t idx) override;37 38private:39 // The lifetime of a ValueObject and all its derivative ValueObjects40 // (children, clones, etc.) is managed by a ClusterManager. These41 // objects are only destroyed when every shared pointer to any of them42 // is destroyed, so we must not store a shared pointer to any ValueObject43 // derived from our backend ValueObject (since we're in the same cluster).44 std::vector<ValueObject *> m_elements;45};46 47} // namespace48 49lldb::ChildCacheState TupleFrontEnd::Update() {50 m_elements.clear();51 52 size_t n_elements = 0;53 for (CompilerType ty = m_backend.GetCompilerType();54 ty.GetNumDirectBaseClasses() > 0;55 ty = ty.GetDirectBaseClassAtIndex(0, nullptr))56 ++n_elements;57 58 m_elements.assign(n_elements, nullptr);59 return lldb::ChildCacheState::eRefetch;60}61 62ValueObjectSP TupleFrontEnd::GetChildAtIndex(uint32_t idx) {63 if (idx >= m_elements.size())64 return nullptr;65 if (m_elements[idx])66 return m_elements[idx]->GetSP();67 68 CompilerType holder_ty = m_backend.GetCompilerType();69 for (uint32_t i = 0; i < idx; i++) {70 holder_ty = holder_ty.GetDirectBaseClassAtIndex(0, nullptr);71 if (!holder_ty.IsValid())72 return nullptr;73 }74 75 ValueObjectSP holder_sp = m_backend.Cast(holder_ty);76 if (!holder_sp)77 return nullptr;78 holder_sp = holder_sp->GetChildMemberWithName("_Myfirst");79 80 if (!holder_sp)81 return nullptr;82 83 ValueObjectSP val_sp = holder_sp->GetChildMemberWithName("_Val");84 if (!val_sp)85 return nullptr;86 87 m_elements[idx] =88 val_sp->Clone(ConstString(llvm::formatv("[{0}]", idx).str())).get();89 return m_elements[idx]->GetSP();90}91 92bool formatters::IsMsvcStlTuple(ValueObject &valobj) {93 // This returns false for empty tuples, but the libstdc++ formatter handles94 // this correctly.95 if (auto valobj_sp = valobj.GetNonSyntheticValue())96 return valobj_sp->GetChildMemberWithName("_Myfirst") != nullptr;97 return false;98}99 100SyntheticChildrenFrontEnd *formatters::MsvcStlTupleSyntheticFrontEndCreator(101 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {102 if (valobj_sp)103 return new TupleFrontEnd(*valobj_sp);104 return nullptr;105}106