147 lines · cpp
1//===-- LibCxxValarray.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 "LibCxx.h"10 11#include "lldb/DataFormatters/FormattersHelpers.h"12#include "lldb/ValueObject/ValueObject.h"13#include <optional>14 15using namespace lldb;16using namespace lldb_private;17using namespace lldb_private::formatters;18 19namespace lldb_private {20namespace formatters {21class LibcxxStdValarraySyntheticFrontEnd : public SyntheticChildrenFrontEnd {22public:23 LibcxxStdValarraySyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);24 25 ~LibcxxStdValarraySyntheticFrontEnd() override;26 27 llvm::Expected<uint32_t> CalculateNumChildren() override;28 29 lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override;30 31 lldb::ChildCacheState Update() override;32 33 llvm::Expected<size_t> GetIndexOfChildWithName(ConstString name) override;34 35private:36 /// A non-owning pointer to valarray's __begin_ member.37 ValueObject *m_start = nullptr;38 /// A non-owning pointer to valarray's __end_ member.39 ValueObject *m_finish = nullptr;40 /// The type of valarray's template argument T.41 CompilerType m_element_type;42 /// The sizeof valarray's template argument T.43 uint32_t m_element_size = 0;44};45 46} // namespace formatters47} // namespace lldb_private48 49lldb_private::formatters::LibcxxStdValarraySyntheticFrontEnd::50 LibcxxStdValarraySyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)51 : SyntheticChildrenFrontEnd(*valobj_sp), m_element_type() {52 if (valobj_sp)53 Update();54}55 56lldb_private::formatters::LibcxxStdValarraySyntheticFrontEnd::57 ~LibcxxStdValarraySyntheticFrontEnd() {58 // these need to stay around because they are child objects who will follow59 // their parent's life cycle60 // delete m_start;61 // delete m_finish;62}63 64llvm::Expected<uint32_t> lldb_private::formatters::65 LibcxxStdValarraySyntheticFrontEnd::CalculateNumChildren() {66 if (!m_start || !m_finish)67 return 0;68 uint64_t start_val = m_start->GetValueAsUnsigned(0);69 uint64_t finish_val = m_finish->GetValueAsUnsigned(0);70 71 if (start_val == 0 || finish_val == 0)72 return 0;73 74 if (start_val >= finish_val)75 return 0;76 77 size_t num_children = (finish_val - start_val);78 if (num_children % m_element_size)79 return 0;80 return num_children / m_element_size;81}82 83lldb::ValueObjectSP84lldb_private::formatters::LibcxxStdValarraySyntheticFrontEnd::GetChildAtIndex(85 uint32_t idx) {86 if (!m_start || !m_finish)87 return lldb::ValueObjectSP();88 89 uint64_t offset = idx * m_element_size;90 offset = offset + m_start->GetValueAsUnsigned(0);91 StreamString name;92 name.Printf("[%" PRIu64 "]", (uint64_t)idx);93 return CreateValueObjectFromAddress(name.GetString(), offset,94 m_backend.GetExecutionContextRef(),95 m_element_type);96}97 98lldb::ChildCacheState99lldb_private::formatters::LibcxxStdValarraySyntheticFrontEnd::Update() {100 m_start = m_finish = nullptr;101 102 CompilerType type = m_backend.GetCompilerType();103 if (type.GetNumTemplateArguments() == 0)104 return ChildCacheState::eRefetch;105 106 m_element_type = type.GetTypeTemplateArgument(0);107 if (std::optional<uint64_t> size =108 llvm::expectedToOptional(m_element_type.GetByteSize(nullptr)))109 m_element_size = *size;110 111 if (m_element_size == 0)112 return ChildCacheState::eRefetch;113 114 ValueObjectSP start = m_backend.GetChildMemberWithName("__begin_");115 ValueObjectSP finish = m_backend.GetChildMemberWithName("__end_");116 117 if (!start || !finish)118 return ChildCacheState::eRefetch;119 120 m_start = start.get();121 m_finish = finish.get();122 123 return ChildCacheState::eRefetch;124}125 126llvm::Expected<size_t>127lldb_private::formatters::LibcxxStdValarraySyntheticFrontEnd::128 GetIndexOfChildWithName(ConstString name) {129 if (!m_start || !m_finish)130 return llvm::createStringError("Type has no child named '%s'",131 name.AsCString());132 auto optional_idx = formatters::ExtractIndexFromString(name.GetCString());133 if (!optional_idx) {134 return llvm::createStringError("Type has no child named '%s'",135 name.AsCString());136 }137 return *optional_idx;138}139 140lldb_private::SyntheticChildrenFrontEnd *141lldb_private::formatters::LibcxxStdValarraySyntheticFrontEndCreator(142 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {143 if (!valobj_sp)144 return nullptr;145 return new LibcxxStdValarraySyntheticFrontEnd(valobj_sp);146}147