| //===-- GenericOptional.cpp ----------------------------------------------===// |
| // |
| // 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 "Generic.h" |
| #include "LibCxx.h" |
| #include "LibStdcpp.h" |
| #include "Plugins/TypeSystem/Clang/TypeSystemClang.h" |
| #include "lldb/DataFormatters/FormattersHelpers.h" |
| #include "lldb/Target/Target.h" |
| |
| using namespace lldb; |
| using namespace lldb_private; |
| |
| bool lldb_private::formatters::GenericOptionalSummaryProvider( |
| ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) { |
| stream.Printf(" Has Value=%s ", |
| valobj.GetNumChildrenIgnoringErrors() == 0 ? "false" : "true"); |
| |
| return true; |
| } |
| |
| // Synthetic Children Provider |
| namespace { |
| |
| class GenericOptionalFrontend : public SyntheticChildrenFrontEnd { |
| public: |
| enum class StdLib { |
| LibCxx, |
| LibStdcpp, |
| }; |
| |
| GenericOptionalFrontend(ValueObject &valobj, StdLib stdlib); |
| |
| size_t GetIndexOfChildWithName(ConstString name) override { |
| return formatters::ExtractIndexFromString(name.GetCString()); |
| } |
| |
| bool MightHaveChildren() override { return true; } |
| llvm::Expected<uint32_t> CalculateNumChildren() override { |
| return m_has_value ? 1U : 0U; |
| } |
| |
| ValueObjectSP GetChildAtIndex(uint32_t idx) override; |
| lldb::ChildCacheState Update() override; |
| |
| private: |
| bool m_has_value = false; |
| StdLib m_stdlib; |
| }; |
| |
| } // namespace |
| |
| GenericOptionalFrontend::GenericOptionalFrontend(ValueObject &valobj, |
| StdLib stdlib) |
| : SyntheticChildrenFrontEnd(valobj), m_stdlib(stdlib) { |
| if (auto target_sp = m_backend.GetTargetSP()) { |
| Update(); |
| } |
| } |
| |
| lldb::ChildCacheState GenericOptionalFrontend::Update() { |
| ValueObjectSP engaged_sp; |
| |
| if (m_stdlib == StdLib::LibCxx) |
| engaged_sp = m_backend.GetChildMemberWithName("__engaged_"); |
| else if (m_stdlib == StdLib::LibStdcpp) |
| engaged_sp = m_backend.GetChildMemberWithName("_M_payload") |
| ->GetChildMemberWithName("_M_engaged"); |
| |
| if (!engaged_sp) |
| return lldb::ChildCacheState::eRefetch; |
| |
| // _M_engaged/__engaged is a bool flag and is true if the optional contains a |
| // value. Converting it to unsigned gives us a size of 1 if it contains a |
| // value and 0 if not. |
| m_has_value = engaged_sp->GetValueAsUnsigned(0) != 0; |
| |
| return lldb::ChildCacheState::eRefetch; |
| } |
| |
| ValueObjectSP GenericOptionalFrontend::GetChildAtIndex(uint32_t _idx) { |
| if (!m_has_value) |
| return ValueObjectSP(); |
| |
| ValueObjectSP val_sp; |
| |
| if (m_stdlib == StdLib::LibCxx) |
| // __val_ contains the underlying value of an optional if it has one. |
| // Currently because it is part of an anonymous union |
| // GetChildMemberWithName() does not peer through and find it unless we are |
| // at the parent itself. We can obtain the parent through __engaged_. |
| val_sp = m_backend.GetChildMemberWithName("__engaged_") |
| ->GetParent() |
| ->GetChildAtIndex(0) |
| ->GetChildMemberWithName("__val_"); |
| else if (m_stdlib == StdLib::LibStdcpp) { |
| val_sp = m_backend.GetChildMemberWithName("_M_payload") |
| ->GetChildMemberWithName("_M_payload"); |
| |
| // In some implementations, _M_value contains the underlying value of an |
| // optional, and in other versions, it's in the payload member. |
| ValueObjectSP candidate = val_sp->GetChildMemberWithName("_M_value"); |
| if (candidate) |
| val_sp = candidate; |
| } |
| |
| if (!val_sp) |
| return ValueObjectSP(); |
| |
| CompilerType holder_type = val_sp->GetCompilerType(); |
| |
| if (!holder_type) |
| return ValueObjectSP(); |
| |
| return val_sp->Clone(ConstString("Value")); |
| } |
| |
| SyntheticChildrenFrontEnd * |
| formatters::LibStdcppOptionalSyntheticFrontEndCreator( |
| CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) { |
| if (valobj_sp) |
| return new GenericOptionalFrontend( |
| *valobj_sp, GenericOptionalFrontend::StdLib::LibStdcpp); |
| return nullptr; |
| } |
| |
| SyntheticChildrenFrontEnd *formatters::LibcxxOptionalSyntheticFrontEndCreator( |
| CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) { |
| if (valobj_sp) |
| return new GenericOptionalFrontend(*valobj_sp, |
| GenericOptionalFrontend::StdLib::LibCxx); |
| return nullptr; |
| } |