299 lines · cpp
1//===-- LibCxxVector.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/Utility/ConstString.h"13#include "lldb/ValueObject/ValueObject.h"14#include "lldb/lldb-enumerations.h"15#include "lldb/lldb-forward.h"16#include <optional>17 18using namespace lldb;19using namespace lldb_private;20using namespace lldb_private::formatters;21 22namespace lldb_private {23namespace formatters {24class LibcxxStdVectorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {25public:26 LibcxxStdVectorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);27 28 ~LibcxxStdVectorSyntheticFrontEnd() override;29 30 llvm::Expected<uint32_t> CalculateNumChildren() override;31 32 lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override;33 34 lldb::ChildCacheState Update() override;35 36 llvm::Expected<size_t> GetIndexOfChildWithName(ConstString name) override;37 38private:39 ValueObject *m_start = nullptr;40 ValueObject *m_finish = nullptr;41 CompilerType m_element_type;42 uint32_t m_element_size = 0;43};44 45class LibcxxVectorBoolSyntheticFrontEnd : public SyntheticChildrenFrontEnd {46public:47 LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);48 49 llvm::Expected<uint32_t> CalculateNumChildren() override;50 51 lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override;52 53 lldb::ChildCacheState Update() override;54 55 llvm::Expected<size_t> GetIndexOfChildWithName(ConstString name) override;56 57private:58 CompilerType m_bool_type;59 ExecutionContextRef m_exe_ctx_ref;60 uint64_t m_count = 0;61 lldb::addr_t m_base_data_address = 0;62 std::map<size_t, lldb::ValueObjectSP> m_children;63};64 65} // namespace formatters66} // namespace lldb_private67 68lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::69 LibcxxStdVectorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)70 : SyntheticChildrenFrontEnd(*valobj_sp), m_element_type() {71 if (valobj_sp)72 Update();73}74 75lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::76 ~LibcxxStdVectorSyntheticFrontEnd() {77 // these need to stay around because they are child objects who will follow78 // their parent's life cycle79 // delete m_start;80 // delete m_finish;81}82 83llvm::Expected<uint32_t> lldb_private::formatters::84 LibcxxStdVectorSyntheticFrontEnd::CalculateNumChildren() {85 if (!m_start || !m_finish)86 return llvm::createStringError(87 "failed to determine start/end of vector data");88 89 uint64_t start_val = m_start->GetValueAsUnsigned(0);90 uint64_t finish_val = m_finish->GetValueAsUnsigned(0);91 92 // A default-initialized empty vector.93 if (start_val == 0 && finish_val == 0)94 return 0;95 96 if (start_val == 0)97 return llvm::createStringError("invalid value for start of vector");98 99 if (finish_val == 0)100 return llvm::createStringError("invalid value for end of vector");101 102 if (start_val > finish_val)103 return llvm::createStringError(104 "start of vector data begins after end pointer");105 106 size_t num_children = (finish_val - start_val);107 if (num_children % m_element_size)108 return llvm::createStringError("size not multiple of element size");109 110 return num_children / m_element_size;111}112 113lldb::ValueObjectSP114lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::GetChildAtIndex(115 uint32_t idx) {116 if (!m_start || !m_finish)117 return lldb::ValueObjectSP();118 119 uint64_t offset = idx * m_element_size;120 offset = offset + m_start->GetValueAsUnsigned(0);121 StreamString name;122 name.Printf("[%" PRIu64 "]", (uint64_t)idx);123 return CreateValueObjectFromAddress(name.GetString(), offset,124 m_backend.GetExecutionContextRef(),125 m_element_type);126}127 128static ValueObjectSP GetDataPointer(ValueObject &root) {129 auto [cap_sp, is_compressed_pair] = GetValueOrOldCompressedPair(130 root, /*anon_struct_idx=*/2, "__cap_", "__end_cap_");131 if (!cap_sp)132 return nullptr;133 134 if (is_compressed_pair)135 return GetFirstValueOfLibCXXCompressedPair(*cap_sp);136 137 return cap_sp;138}139 140lldb::ChildCacheState141lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update() {142 m_start = m_finish = nullptr;143 ValueObjectSP data_sp(GetDataPointer(m_backend));144 145 if (!data_sp)146 return lldb::ChildCacheState::eRefetch;147 148 m_element_type = data_sp->GetCompilerType().GetPointeeType();149 llvm::Expected<uint64_t> size_or_err = m_element_type.GetByteSize(nullptr);150 if (!size_or_err)151 LLDB_LOG_ERRORV(GetLog(LLDBLog::DataFormatters), size_or_err.takeError(),152 "{0}");153 else {154 m_element_size = *size_or_err;155 156 if (m_element_size > 0) {157 // store raw pointers or end up with a circular dependency158 m_start = m_backend.GetChildMemberWithName("__begin_").get();159 m_finish = m_backend.GetChildMemberWithName("__end_").get();160 }161 }162 return lldb::ChildCacheState::eRefetch;163}164 165llvm::Expected<size_t>166lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::167 GetIndexOfChildWithName(ConstString name) {168 if (!m_start || !m_finish)169 return llvm::createStringError("Type has no child named '%s'",170 name.AsCString());171 auto optional_idx = formatters::ExtractIndexFromString(name.GetCString());172 if (!optional_idx) {173 return llvm::createStringError("Type has no child named '%s'",174 name.AsCString());175 }176 return *optional_idx;177}178 179lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::180 LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)181 : SyntheticChildrenFrontEnd(*valobj_sp), m_bool_type(), m_exe_ctx_ref(),182 m_children() {183 if (valobj_sp) {184 Update();185 m_bool_type =186 valobj_sp->GetCompilerType().GetBasicTypeFromAST(lldb::eBasicTypeBool);187 }188}189 190llvm::Expected<uint32_t> lldb_private::formatters::191 LibcxxVectorBoolSyntheticFrontEnd::CalculateNumChildren() {192 return m_count;193}194 195lldb::ValueObjectSP196lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::GetChildAtIndex(197 uint32_t idx) {198 auto iter = m_children.find(idx), end = m_children.end();199 if (iter != end)200 return iter->second;201 if (idx >= m_count)202 return {};203 if (m_base_data_address == 0 || m_count == 0)204 return {};205 if (!m_bool_type)206 return {};207 size_t byte_idx = (idx >> 3); // divide by 8 to get byte index208 size_t bit_index = (idx & 7); // efficient idx % 8 for bit index209 lldb::addr_t byte_location = m_base_data_address + byte_idx;210 ProcessSP process_sp(m_exe_ctx_ref.GetProcessSP());211 if (!process_sp)212 return {};213 uint8_t byte = 0;214 uint8_t mask = 0;215 Status err;216 size_t bytes_read = process_sp->ReadMemory(byte_location, &byte, 1, err);217 if (err.Fail() || bytes_read == 0)218 return {};219 mask = 1 << bit_index;220 bool bit_set = ((byte & mask) != 0);221 std::optional<uint64_t> size =222 llvm::expectedToOptional(m_bool_type.GetByteSize(nullptr));223 if (!size)224 return {};225 WritableDataBufferSP buffer_sp(new DataBufferHeap(*size, 0));226 if (bit_set && buffer_sp && buffer_sp->GetBytes()) {227 // regardless of endianness, anything non-zero is true228 *(buffer_sp->GetBytes()) = 1;229 }230 StreamString name;231 name.Printf("[%" PRIu64 "]", (uint64_t)idx);232 ValueObjectSP retval_sp(CreateValueObjectFromData(233 name.GetString(),234 DataExtractor(buffer_sp, process_sp->GetByteOrder(),235 process_sp->GetAddressByteSize()),236 m_exe_ctx_ref, m_bool_type));237 if (retval_sp)238 m_children[idx] = retval_sp;239 return retval_sp;240}241 242lldb::ChildCacheState243lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::Update() {244 m_children.clear();245 ValueObjectSP valobj_sp = m_backend.GetSP();246 if (!valobj_sp)247 return lldb::ChildCacheState::eRefetch;248 m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();249 ValueObjectSP size_sp(valobj_sp->GetChildMemberWithName("__size_"));250 if (!size_sp)251 return lldb::ChildCacheState::eRefetch;252 m_count = size_sp->GetValueAsUnsigned(0);253 if (!m_count)254 return lldb::ChildCacheState::eReuse;255 ValueObjectSP begin_sp(valobj_sp->GetChildMemberWithName("__begin_"));256 if (!begin_sp) {257 m_count = 0;258 return lldb::ChildCacheState::eRefetch;259 }260 m_base_data_address = begin_sp->GetValueAsUnsigned(0);261 if (!m_base_data_address) {262 m_count = 0;263 return lldb::ChildCacheState::eRefetch;264 }265 return lldb::ChildCacheState::eRefetch;266}267 268llvm::Expected<size_t>269lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::270 GetIndexOfChildWithName(ConstString name) {271 if (!m_count || !m_base_data_address)272 return llvm::createStringError("Type has no child named '%s'",273 name.AsCString());274 auto optional_idx = ExtractIndexFromString(name.AsCString());275 if (!optional_idx) {276 return llvm::createStringError("Type has no child named '%s'",277 name.AsCString());278 }279 uint32_t idx = *optional_idx;280 if (idx >= CalculateNumChildrenIgnoringErrors())281 return llvm::createStringError("Type has no child named '%s'",282 name.AsCString());283 return idx;284}285 286lldb_private::SyntheticChildrenFrontEnd *287lldb_private::formatters::LibcxxStdVectorSyntheticFrontEndCreator(288 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {289 if (!valobj_sp)290 return nullptr;291 CompilerType type = valobj_sp->GetCompilerType();292 if (!type.IsValid() || type.GetNumTemplateArguments() == 0)293 return nullptr;294 CompilerType arg_type = type.GetTypeTemplateArgument(0);295 if (arg_type.GetTypeName() == "bool")296 return new LibcxxVectorBoolSyntheticFrontEnd(valobj_sp);297 return new LibcxxStdVectorSyntheticFrontEnd(valobj_sp);298}299