| 1 | //===-- LibCxxTuple.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-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #include "LibCxx.h" |
| 10 | #include "lldb/DataFormatters/FormattersHelpers.h" |
| 11 | |
| 12 | using namespace lldb; |
| 13 | using namespace lldb_private; |
| 14 | |
| 15 | namespace { |
| 16 | |
| 17 | class TupleFrontEnd: public SyntheticChildrenFrontEnd { |
| 18 | public: |
| 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(item_name: name.GetCString()); |
| 25 | if (!optional_idx) { |
| 26 | return llvm::createStringError(Fmt: "Type has no child named '%s'", |
| 27 | Vals: 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 | |
| 38 | private: |
| 39 | // The lifetime of a ValueObject and all its derivative ValueObjects |
| 40 | // (children, clones, etc.) is managed by a ClusterManager. These |
| 41 | // objects are only destroyed when every shared pointer to any of them |
| 42 | // is destroyed, so we must not store a shared pointer to any ValueObject |
| 43 | // derived from our backend ValueObject (since we're in the same cluster). |
| 44 | std::vector<ValueObject*> m_elements; |
| 45 | ValueObject* m_base = nullptr; |
| 46 | }; |
| 47 | } |
| 48 | |
| 49 | lldb::ChildCacheState TupleFrontEnd::Update() { |
| 50 | m_elements.clear(); |
| 51 | m_base = nullptr; |
| 52 | |
| 53 | ValueObjectSP base_sp; |
| 54 | base_sp = m_backend.GetChildMemberWithName(name: "__base_"); |
| 55 | if (!base_sp) { |
| 56 | // Pre r304382 name of the base element. |
| 57 | base_sp = m_backend.GetChildMemberWithName(name: "base_"); |
| 58 | } |
| 59 | if (!base_sp) |
| 60 | return lldb::ChildCacheState::eRefetch; |
| 61 | m_base = base_sp.get(); |
| 62 | m_elements.assign(n: base_sp->GetCompilerType().GetNumDirectBaseClasses(), |
| 63 | val: nullptr); |
| 64 | return lldb::ChildCacheState::eRefetch; |
| 65 | } |
| 66 | |
| 67 | ValueObjectSP TupleFrontEnd::GetChildAtIndex(uint32_t idx) { |
| 68 | if (idx >= m_elements.size()) |
| 69 | return ValueObjectSP(); |
| 70 | if (!m_base) |
| 71 | return ValueObjectSP(); |
| 72 | if (m_elements[idx]) |
| 73 | return m_elements[idx]->GetSP(); |
| 74 | |
| 75 | CompilerType holder_type = |
| 76 | m_base->GetCompilerType().GetDirectBaseClassAtIndex(idx, bit_offset_ptr: nullptr); |
| 77 | if (!holder_type) |
| 78 | return ValueObjectSP(); |
| 79 | ValueObjectSP holder_sp = m_base->GetChildAtIndex(idx); |
| 80 | if (!holder_sp) |
| 81 | return ValueObjectSP(); |
| 82 | |
| 83 | ValueObjectSP elem_sp = holder_sp->GetChildAtIndex(idx: 0); |
| 84 | if (elem_sp) |
| 85 | m_elements[idx] = |
| 86 | elem_sp->Clone(new_name: ConstString(llvm::formatv(Fmt: "[{0}]", Vals&: idx).str())).get(); |
| 87 | |
| 88 | if (m_elements[idx]) |
| 89 | return m_elements[idx]->GetSP(); |
| 90 | return ValueObjectSP(); |
| 91 | } |
| 92 | |
| 93 | SyntheticChildrenFrontEnd * |
| 94 | formatters::LibcxxTupleFrontEndCreator(CXXSyntheticChildren *, |
| 95 | lldb::ValueObjectSP valobj_sp) { |
| 96 | if (valobj_sp) |
| 97 | return new TupleFrontEnd(*valobj_sp); |
| 98 | return nullptr; |
| 99 | } |
| 100 |