Because of our lifetime rules w.r.t. ValueObjects and ClusterManagers, synthetic children caching is a tricky area:
- if a synthetic child comes from the same hierarchy as its parent object, then it can't be cached by SharedPointer inside the synthetic provider, or it will cause a reference loop;
- but, if a synthetic child is made from whole cloth (e.g. from an expression, a memory region, ...), then it better be cached by SharedPointer, or it will be cleared out and cause an assert() to fail if used at a later point
For most cases of self-rooted synthetic children, we have a flag we set "IsSyntheticChildrenGenerated", but we were not using it to track caching. So, what ended up happening is each provider would set up its own cache, and if it got it wrong, a hard to diagnose crash would ensue
This patch fixes that by centralizing caching in ValueObjectSynthetic - if a provider returns a self-rooted child (as per the flag), then it gets cached centrally by the ValueObject itself
This cache is used only for lifetime management and not later retrieval of child values - a different cache handles that (because we might have a mix of self-rooted and properly nested child values for the same parent, we can't trivially use this lifetime cache for retrieval)
Fixes rdar://26480007
llvm-svn: 274683
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp
index 71a94b7..54fddd1 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp
@@ -50,7 +50,6 @@
CompilerType m_element_type;
uint32_t m_element_size;
size_t m_num_elements;
- std::map<size_t,lldb::ValueObjectSP> m_children;
};
} // namespace formatters
} // namespace lldb_private
@@ -60,8 +59,7 @@
m_start(nullptr),
m_element_type(),
m_element_size(0),
- m_num_elements(0),
- m_children()
+ m_num_elements(0)
{
if (valobj_sp)
Update();
@@ -90,17 +88,11 @@
if (!m_start)
return lldb::ValueObjectSP();
- auto cached = m_children.find(idx);
- if (cached != m_children.end())
- return cached->second;
-
uint64_t offset = idx * m_element_size;
offset = offset + m_start->GetValueAsUnsigned(0);
StreamString name;
name.Printf("[%" PRIu64 "]", (uint64_t)idx);
- ValueObjectSP child_sp = CreateValueObjectFromAddress(name.GetData(), offset, m_backend.GetExecutionContextRef(), m_element_type);
- m_children[idx] = child_sp;
- return child_sp;
+ return CreateValueObjectFromAddress(name.GetData(), offset, m_backend.GetExecutionContextRef(), m_element_type);
}
bool
@@ -110,7 +102,6 @@
m_start = nullptr;
m_num_elements = 0;
- m_children.clear();
lldb::TemplateArgumentKind kind;
m_element_type = m_backend.GetCompilerType().GetTemplateArgument(0, kind);
if (kind != lldb::eTemplateArgumentKindType || !m_element_type.IsValid())
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxList.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxList.cpp
index 8e089ae..35cee56 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxxList.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxxList.cpp
@@ -200,7 +200,6 @@
ValueObject* m_tail;
CompilerType m_element_type;
size_t m_count;
- std::map<size_t,lldb::ValueObjectSP> m_children;
std::map<size_t, ListIterator> m_iterators;
};
} // namespace formatters
@@ -215,7 +214,6 @@
m_tail(nullptr),
m_element_type(),
m_count(UINT32_MAX),
- m_children(),
m_iterators()
{
if (valobj_sp)
@@ -312,10 +310,6 @@
if (!m_head || !m_tail || m_node_address == 0)
return lldb::ValueObjectSP();
- auto cached = m_children.find(idx);
- if (cached != m_children.end())
- return cached->second;
-
if (HasLoop(idx+1))
return lldb::ValueObjectSP();
@@ -350,13 +344,15 @@
StreamString name;
name.Printf("[%" PRIu64 "]", (uint64_t)idx);
- return (m_children[idx] = CreateValueObjectFromData(name.GetData(), data, m_backend.GetExecutionContextRef(), m_element_type));
+ return CreateValueObjectFromData(name.GetData(),
+ data,
+ m_backend.GetExecutionContextRef(),
+ m_element_type);
}
bool
lldb_private::formatters::LibcxxStdListSyntheticFrontEnd::Update()
{
- m_children.clear();
m_iterators.clear();
m_head = m_tail = nullptr;
m_node_address = 0;
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxMap.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxMap.cpp
index 7e50c21..d898692 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxxMap.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxxMap.cpp
@@ -246,7 +246,6 @@
CompilerType m_element_type;
uint32_t m_skip_size;
size_t m_count;
- std::map<size_t, lldb::ValueObjectSP> m_children;
std::map<size_t, MapIterator> m_iterators;
};
} // namespace formatters
@@ -259,7 +258,6 @@
m_element_type(),
m_skip_size(UINT32_MAX),
m_count(UINT32_MAX),
- m_children(),
m_iterators()
{
if (valobj_sp)
@@ -332,10 +330,6 @@
if (m_tree == nullptr || m_root_node == nullptr)
return lldb::ValueObjectSP();
- auto cached = m_children.find(idx);
- if (cached != m_children.end())
- return cached->second;
-
MapIterator iterator(m_root_node, CalculateNumChildren());
const bool need_to_skip = (idx > 0);
@@ -437,7 +431,7 @@
potential_child_sp->SetName(ConstString(name.GetData()));
}
m_iterators[idx] = iterator;
- return (m_children[idx] = potential_child_sp);
+ return potential_child_sp;
}
bool
@@ -447,7 +441,6 @@
static ConstString g___begin_node_("__begin_node_");
m_count = UINT32_MAX;
m_tree = m_root_node = nullptr;
- m_children.clear();
m_iterators.clear();
m_tree = m_backend.GetChildMemberWithName(g___tree_, true).get();
if (!m_tree)
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxUnorderedMap.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxUnorderedMap.cpp
index 5424776..a547695 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxxUnorderedMap.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxxUnorderedMap.cpp
@@ -55,7 +55,6 @@
ValueObject* m_tree;
size_t m_num_elements;
ValueObject* m_next_element;
- std::map<size_t,lldb::ValueObjectSP> m_children;
std::vector<std::pair<ValueObject*, uint64_t> > m_elements_cache;
};
} // namespace formatters
@@ -66,7 +65,6 @@
m_tree(nullptr),
m_num_elements(0),
m_next_element(nullptr),
- m_children(),
m_elements_cache()
{
if (valobj_sp)
@@ -89,10 +87,6 @@
if (m_tree == nullptr)
return lldb::ValueObjectSP();
- auto cached = m_children.find(idx);
- if (cached != m_children.end())
- return cached->second;
-
while (idx >= m_elements_cache.size())
{
if (m_next_element == nullptr)
@@ -125,13 +119,10 @@
return lldb::ValueObjectSP();
const bool thread_and_frame_only_if_stopped = true;
ExecutionContext exe_ctx = val_hash.first->GetExecutionContextRef().Lock(thread_and_frame_only_if_stopped);
- ValueObjectSP child_sp(val_hash.first->CreateValueObjectFromData(stream.GetData(),
- data,
- exe_ctx,
- val_hash.first->GetCompilerType()));
- if (child_sp)
- m_children.emplace(idx, child_sp);
- return child_sp;
+ return CreateValueObjectFromData(stream.GetData(),
+ data,
+ exe_ctx,
+ val_hash.first->GetCompilerType());
}
bool
@@ -140,7 +131,6 @@
m_num_elements = UINT32_MAX;
m_next_element = nullptr;
m_elements_cache.clear();
- m_children.clear();
ValueObjectSP table_sp = m_backend.GetChildMemberWithName(ConstString("__table_"), true);
if (!table_sp)
return false;
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxVector.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxVector.cpp
index b39ea51..ed26eae 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxxVector.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxxVector.cpp
@@ -50,7 +50,6 @@
ValueObject* m_finish;
CompilerType m_element_type;
uint32_t m_element_size;
- std::map<size_t,lldb::ValueObjectSP> m_children;
};
} // namespace formatters
} // namespace lldb_private
@@ -60,8 +59,7 @@
m_start(nullptr),
m_finish(nullptr),
m_element_type(),
- m_element_size(0),
- m_children()
+ m_element_size(0)
{
if (valobj_sp)
Update();
@@ -100,24 +98,20 @@
if (!m_start || !m_finish)
return lldb::ValueObjectSP();
- auto cached = m_children.find(idx);
- if (cached != m_children.end())
- return cached->second;
-
uint64_t offset = idx * m_element_size;
offset = offset + m_start->GetValueAsUnsigned(0);
StreamString name;
name.Printf("[%" PRIu64 "]", (uint64_t)idx);
- ValueObjectSP child_sp = CreateValueObjectFromAddress(name.GetData(), offset, m_backend.GetExecutionContextRef(), m_element_type);
- m_children[idx] = child_sp;
- return child_sp;
+ return CreateValueObjectFromAddress(name.GetData(),
+ offset,
+ m_backend.GetExecutionContextRef(),
+ m_element_type);
}
bool
lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update()
{
m_start = m_finish = nullptr;
- m_children.clear();
ValueObjectSP data_type_finder_sp(m_backend.GetChildMemberWithName(ConstString("__end_cap_"),true));
if (!data_type_finder_sp)
return false;