1 //===-- LibCxxUnorderedMap.cpp --------------------------------------------===//
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
7 //===----------------------------------------------------------------------===//
11 #include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
12 #include "lldb/Core/ValueObject.h"
13 #include "lldb/Core/ValueObjectConstResult.h"
14 #include "lldb/DataFormatters/FormattersHelpers.h"
15 #include "lldb/Target/Target.h"
16 #include "lldb/Utility/ConstString.h"
17 #include "lldb/Utility/DataBufferHeap.h"
18 #include "lldb/Utility/Endian.h"
19 #include "lldb/Utility/Status.h"
20 #include "lldb/Utility/Stream.h"
21 #include "llvm/ADT/StringRef.h"
24 using namespace lldb_private;
25 using namespace lldb_private::formatters;
27 namespace lldb_private {
28 namespace formatters {
29 class LibcxxStdUnorderedMapSyntheticFrontEnd
30 : public SyntheticChildrenFrontEnd {
32 LibcxxStdUnorderedMapSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
34 ~LibcxxStdUnorderedMapSyntheticFrontEnd() override = default;
36 size_t CalculateNumChildren() override;
38 lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
40 bool Update() override;
42 bool MightHaveChildren() override;
44 size_t GetIndexOfChildWithName(ConstString name) override;
47 CompilerType m_element_type;
48 CompilerType m_node_type;
49 ValueObject *m_tree = nullptr;
50 size_t m_num_elements = 0;
51 ValueObject *m_next_element = nullptr;
52 std::vector<std::pair<ValueObject *, uint64_t>> m_elements_cache;
54 } // namespace formatters
55 } // namespace lldb_private
57 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::
58 LibcxxStdUnorderedMapSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
59 : SyntheticChildrenFrontEnd(*valobj_sp), m_element_type(),
65 size_t lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::
66 CalculateNumChildren() {
67 return m_num_elements;
70 static void consumeInlineNamespace(llvm::StringRef &name) {
71 // Delete past an inline namespace, if any: __[a-zA-Z0-9_]+::
73 if (scratch.consume_front("__") && std::isalnum(scratch[0])) {
74 scratch = scratch.drop_while([](char c) { return std::isalnum(c); });
75 if (scratch.consume_front("::")) {
76 // Successfully consumed a namespace.
82 static bool isStdTemplate(ConstString type_name, llvm::StringRef type) {
83 llvm::StringRef name = type_name.GetStringRef();
84 // The type name may be prefixed with `std::__<inline-namespace>::`.
85 if (name.consume_front("std::"))
86 consumeInlineNamespace(name);
87 return name.consume_front(type) && name.startswith("<");
90 static bool isUnorderedMap(ConstString type_name) {
91 return isStdTemplate(type_name, "unordered_map") ||
92 isStdTemplate(type_name, "unordered_multimap");
95 lldb::ValueObjectSP lldb_private::formatters::
96 LibcxxStdUnorderedMapSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
97 if (idx >= CalculateNumChildren())
98 return lldb::ValueObjectSP();
99 if (m_tree == nullptr)
100 return lldb::ValueObjectSP();
102 while (idx >= m_elements_cache.size()) {
103 if (m_next_element == nullptr)
104 return lldb::ValueObjectSP();
107 ValueObjectSP node_sp = m_next_element->Dereference(error);
108 if (!node_sp || error.Fail())
109 return lldb::ValueObjectSP();
111 ValueObjectSP value_sp = node_sp->GetChildMemberWithName("__value_");
112 ValueObjectSP hash_sp = node_sp->GetChildMemberWithName("__hash_");
113 if (!hash_sp || !value_sp) {
114 if (!m_element_type) {
115 auto p1_sp = m_backend.GetChildAtNamePath({"__table_", "__p1_"});
119 ValueObjectSP first_sp = nullptr;
120 switch (p1_sp->GetCompilerType().GetNumDirectBaseClasses()) {
122 // Assume a pre llvm r300140 __compressed_pair implementation:
123 first_sp = p1_sp->GetChildMemberWithName("__first_");
126 // Assume a post llvm r300140 __compressed_pair implementation:
127 ValueObjectSP first_elem_parent_sp =
128 p1_sp->GetChildAtIndex(0);
129 first_sp = p1_sp->GetChildMemberWithName("__value_");
138 m_element_type = first_sp->GetCompilerType();
139 m_element_type = m_element_type.GetTypeTemplateArgument(0);
140 m_element_type = m_element_type.GetPointeeType();
141 m_node_type = m_element_type;
142 m_element_type = m_element_type.GetTypeTemplateArgument(0);
143 // This synthetic provider is used for both unordered_(multi)map and
144 // unordered_(multi)set. For unordered_map, the element type has an
145 // additional type layer, an internal struct (`__hash_value_type`)
146 // that wraps a std::pair. Peel away the internal wrapper type - whose
147 // structure is of no value to users, to expose the std::pair. This
148 // matches the structure returned by the std::map synthetic provider.
149 if (isUnorderedMap(m_backend.GetTypeName())) {
151 CompilerType field_type = m_element_type.GetFieldAtIndex(
152 0, name, nullptr, nullptr, nullptr);
153 CompilerType actual_type = field_type.GetTypedefedType();
154 if (isStdTemplate(actual_type.GetTypeName(), "pair"))
155 m_element_type = actual_type;
160 node_sp = m_next_element->Cast(m_node_type.GetPointerType())
161 ->Dereference(error);
162 if (!node_sp || error.Fail())
165 value_sp = node_sp->GetChildMemberWithName("__value_");
166 hash_sp = node_sp->GetChildMemberWithName("__hash_");
167 if (!value_sp || !hash_sp)
170 m_elements_cache.push_back(
171 {value_sp.get(), hash_sp->GetValueAsUnsigned(0)});
172 m_next_element = node_sp->GetChildMemberWithName("__next_").get();
173 if (!m_next_element || m_next_element->GetValueAsUnsigned(0) == 0)
174 m_next_element = nullptr;
177 std::pair<ValueObject *, uint64_t> val_hash = m_elements_cache[idx];
179 return lldb::ValueObjectSP();
181 stream.Printf("[%" PRIu64 "]", (uint64_t)idx);
184 val_hash.first->GetData(data, error);
186 return lldb::ValueObjectSP();
187 const bool thread_and_frame_only_if_stopped = true;
188 ExecutionContext exe_ctx = val_hash.first->GetExecutionContextRef().Lock(
189 thread_and_frame_only_if_stopped);
190 return CreateValueObjectFromData(stream.GetString(), data, exe_ctx,
194 bool lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::
197 m_next_element = nullptr;
198 m_elements_cache.clear();
199 ValueObjectSP table_sp = m_backend.GetChildMemberWithName("__table_");
203 ValueObjectSP p2_sp = table_sp->GetChildMemberWithName("__p2_");
204 ValueObjectSP num_elements_sp = nullptr;
205 llvm::SmallVector<llvm::StringRef, 3> next_path;
206 switch (p2_sp->GetCompilerType().GetNumDirectBaseClasses()) {
208 // Assume a pre llvm r300140 __compressed_pair implementation:
209 num_elements_sp = p2_sp->GetChildMemberWithName("__first_");
210 next_path.append({"__p1_", "__first_", "__next_"});
213 // Assume a post llvm r300140 __compressed_pair implementation:
214 ValueObjectSP first_elem_parent = p2_sp->GetChildAtIndex(0);
215 num_elements_sp = first_elem_parent->GetChildMemberWithName("__value_");
216 next_path.append({"__p1_", "__value_", "__next_"});
223 if (!num_elements_sp)
226 m_tree = table_sp->GetChildAtNamePath(next_path).get();
227 if (m_tree == nullptr)
230 m_num_elements = num_elements_sp->GetValueAsUnsigned(0);
232 if (m_num_elements > 0)
234 table_sp->GetChildAtNamePath(next_path).get();
238 bool lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::
239 MightHaveChildren() {
243 size_t lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::
244 GetIndexOfChildWithName(ConstString name) {
245 return ExtractIndexFromString(name.GetCString());
248 SyntheticChildrenFrontEnd *
249 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEndCreator(
250 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
251 return (valobj_sp ? new LibcxxStdUnorderedMapSyntheticFrontEnd(valobj_sp)