[lldb][Formatters] Add shared/weak count to libstdc++ std::shared_ptr summary #147166
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…rs consistent with each other
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@llvm/pr-subscribers-lldb Author: Michael Buch (Michael137) ChangesDepends on #147165 This adds weak/strong counts to the std::shared_ptr summary of the libstdcxx formatters. We already do this for libcxx. This will make it easier to consolidate the tests into a generic one (see #147141). Full diff: https://github.com/llvm/llvm-project/pull/147166.diff 3 Files Affected:
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
index 104521b8c3e71..aa13e66a1b550 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
@@ -238,7 +238,8 @@ lldb_private::formatters::LibCxxVectorIteratorSyntheticFrontEndCreator(
lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::
LibcxxSharedPtrSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
- : SyntheticChildrenFrontEnd(*valobj_sp), m_cntrl(nullptr) {
+ : SyntheticChildrenFrontEnd(*valobj_sp), m_cntrl(nullptr),
+ m_ptr_obj(nullptr) {
if (valobj_sp)
Update();
}
@@ -251,7 +252,7 @@ llvm::Expected<uint32_t> lldb_private::formatters::
lldb::ValueObjectSP
lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::GetChildAtIndex(
uint32_t idx) {
- if (!m_cntrl)
+ if (!m_cntrl || !m_ptr_obj)
return lldb::ValueObjectSP();
ValueObjectSP valobj_sp = m_backend.GetSP();
@@ -259,20 +260,17 @@ lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::GetChildAtIndex(
return lldb::ValueObjectSP();
if (idx == 0)
- return valobj_sp->GetChildMemberWithName("__ptr_");
+ return m_ptr_obj->GetSP();
if (idx == 1) {
- if (auto ptr_sp = valobj_sp->GetChildMemberWithName("__ptr_")) {
- Status status;
- auto value_type_sp =
- valobj_sp->GetCompilerType()
- .GetTypeTemplateArgument(0).GetPointerType();
- ValueObjectSP cast_ptr_sp = ptr_sp->Cast(value_type_sp);
- ValueObjectSP value_sp = cast_ptr_sp->Dereference(status);
- if (status.Success()) {
- return value_sp;
- }
- }
+ Status status;
+ auto value_type_sp = valobj_sp->GetCompilerType()
+ .GetTypeTemplateArgument(0)
+ .GetPointerType();
+ ValueObjectSP cast_ptr_sp = m_ptr_obj->Cast(value_type_sp);
+ ValueObjectSP value_sp = cast_ptr_sp->Dereference(status);
+ if (status.Success())
+ return value_sp;
}
return lldb::ValueObjectSP();
@@ -281,6 +279,7 @@ lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::GetChildAtIndex(
lldb::ChildCacheState
lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::Update() {
m_cntrl = nullptr;
+ m_ptr_obj = nullptr;
ValueObjectSP valobj_sp = m_backend.GetSP();
if (!valobj_sp)
@@ -290,6 +289,12 @@ lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::Update() {
if (!target_sp)
return lldb::ChildCacheState::eRefetch;
+ auto ptr_obj_sp = valobj_sp->GetChildMemberWithName("__ptr_");
+ if (!ptr_obj_sp)
+ return lldb::ChildCacheState::eRefetch;
+
+ m_ptr_obj = ptr_obj_sp->Clone(ConstString("pointer")).get();
+
lldb::ValueObjectSP cntrl_sp(valobj_sp->GetChildMemberWithName("__cntrl_"));
m_cntrl = cntrl_sp.get(); // need to store the raw pointer to avoid a circular
@@ -300,10 +305,12 @@ lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::Update() {
llvm::Expected<size_t>
lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::
GetIndexOfChildWithName(ConstString name) {
- if (name == "__ptr_")
+ if (name == "__ptr_" || name == "pointer")
return 0;
- if (name == "$$dereference$$")
+
+ if (name == "object" || name == "$$dereference$$")
return 1;
+
return llvm::createStringError("Type has no child named '%s'",
name.AsCString());
}
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.h b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.h
index 56501302d116f..6115ccde38ad2 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.h
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.h
@@ -108,6 +108,7 @@ class LibcxxSharedPtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
private:
ValueObject *m_cntrl;
+ ValueObject *m_ptr_obj;
};
class LibcxxUniquePtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibStdcpp.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibStdcpp.cpp
index 28b7c01ab1b5b..5862a1ff3eac3 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibStdcpp.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibStdcpp.cpp
@@ -9,6 +9,7 @@
#include "LibStdcpp.h"
#include "LibCxx.h"
+#include "lldb/DataFormatters/FormattersHelpers.h"
#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
#include "lldb/DataFormatters/StringPrinter.h"
#include "lldb/DataFormatters/VectorIterator.h"
@@ -77,8 +78,7 @@ class LibStdcppSharedPtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
// objects are only destroyed when every shared pointer to any of them
// is destroyed, so we must not store a shared pointer to any ValueObject
// derived from our backend ValueObject (since we're in the same cluster).
- ValueObject* m_ptr_obj = nullptr; // Underlying pointer (held, not owned)
- ValueObject* m_obj_obj = nullptr; // Underlying object (held, not owned)
+ ValueObject *m_ptr_obj = nullptr; // Underlying pointer (held, not owned)
};
} // end of anonymous namespace
@@ -266,15 +266,20 @@ LibStdcppSharedPtrSyntheticFrontEnd::GetChildAtIndex(uint32_t idx) {
if (idx == 0)
return m_ptr_obj->GetSP();
+
if (idx == 1) {
- if (m_ptr_obj && !m_obj_obj) {
- Status error;
- ValueObjectSP obj_obj = m_ptr_obj->Dereference(error);
- if (error.Success())
- m_obj_obj = obj_obj->Clone(ConstString("object")).get();
- }
- if (m_obj_obj)
- return m_obj_obj->GetSP();
+ ValueObjectSP valobj_sp = m_backend.GetSP();
+ if (!valobj_sp)
+ return nullptr;
+
+ Status status;
+ auto value_type_sp = valobj_sp->GetCompilerType()
+ .GetTypeTemplateArgument(0)
+ .GetPointerType();
+ ValueObjectSP cast_ptr_sp = m_ptr_obj->Cast(value_type_sp);
+ ValueObjectSP value_sp = cast_ptr_sp->Dereference(status);
+ if (status.Success())
+ return value_sp;
}
return lldb::ValueObjectSP();
}
@@ -293,7 +298,6 @@ lldb::ChildCacheState LibStdcppSharedPtrSyntheticFrontEnd::Update() {
return lldb::ChildCacheState::eRefetch;
m_ptr_obj = ptr_obj_sp->Clone(ConstString("pointer")).get();
- m_obj_obj = nullptr;
return lldb::ChildCacheState::eRefetch;
}
@@ -302,8 +306,10 @@ llvm::Expected<size_t>
LibStdcppSharedPtrSyntheticFrontEnd::GetIndexOfChildWithName(ConstString name) {
if (name == "pointer")
return 0;
+
if (name == "object" || name == "$$dereference$$")
return 1;
+
return llvm::createStringError("Type has no child named '%s'",
name.AsCString());
}
@@ -325,29 +331,37 @@ bool lldb_private::formatters::LibStdcppSmartPointerSummaryProvider(
if (!ptr_sp)
return false;
- ValueObjectSP usecount_sp(
- valobj_sp->GetChildAtNamePath({"_M_refcount", "_M_pi", "_M_use_count"}));
- if (!usecount_sp)
+ DumpCxxSmartPtrPointerSummary(stream, *ptr_sp, options);
+
+ ValueObjectSP pi_sp = valobj_sp->GetChildAtNamePath({"_M_refcount", "_M_pi"});
+ if (!pi_sp)
return false;
- if (ptr_sp->GetValueAsUnsigned(0) == 0 ||
- usecount_sp->GetValueAsUnsigned(0) == 0) {
- stream.Printf("nullptr");
+ bool success;
+ uint64_t pi_addr = pi_sp->GetValueAsUnsigned(0, &success);
+ // Empty control field. We're done.
+ if (!success || pi_addr == 0)
return true;
+
+ int64_t shared_count = 0;
+ if (auto count_sp = pi_sp->GetChildMemberWithName("_M_use_count")) {
+ bool success;
+ shared_count = count_sp->GetValueAsSigned(0, &success);
+ if (!success)
+ return false;
+
+ stream.Printf(" strong=%" PRId64, shared_count);
}
- Status error;
- ValueObjectSP pointee_sp = ptr_sp->Dereference(error);
- if (pointee_sp && error.Success()) {
- if (pointee_sp->DumpPrintableRepresentation(
- stream, ValueObject::eValueObjectRepresentationStyleSummary,
- lldb::eFormatInvalid,
- ValueObject::PrintableRepresentationSpecialCases::eDisable,
- false)) {
- return true;
- }
+ // _M_weak_count is the number of weak references + (_M_use_count != 0).
+ if (auto weak_count_sp = pi_sp->GetChildMemberWithName("_M_weak_count")) {
+ bool success;
+ int64_t count = weak_count_sp->GetValueAsUnsigned(0, &success);
+ if (!success)
+ return false;
+
+ stream.Printf(" weak=%" PRId64, count - (shared_count != 0));
}
- stream.Printf("ptr = 0x%" PRIx64, ptr_sp->GetValueAsUnsigned(0));
return true;
}
|
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✅ With the latest revision this PR passed the C/C++ code formatter. |
labath
approved these changes
Jul 7, 2025
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Depends on #147165
This adds weak/strong counts to the std::shared_ptr summary of the libstdcxx formatters. We already do this for libcxx. This will make it easier to consolidate the tests into a generic one (see #147141).