[Lldb-commits] [lldb] [lldb][DataFormatter] Format libstdc++ unique_ptr like we do libc++ (PR #146909)
Michael Buch via lldb-commits
lldb-commits at lists.llvm.org
Thu Jul 3 09:29:41 PDT 2025
https://github.com/Michael137 updated https://github.com/llvm/llvm-project/pull/146909
>From 9963727a56237f9424642bb1cc12e800640fbd0e Mon Sep 17 00:00:00 2001
From: Michael Buch <michaelbuch12 at gmail.com>
Date: Thu, 3 Jul 2025 16:07:11 +0100
Subject: [PATCH 1/4] [lldb][DataFormatter] Format libstdc++ unique_ptr like we
do libc++
The only difference is that with libc++ the summary string contains the
derefernced pointer value. With libstdc++ we currently display the
pointer itself, which seems redundant. E.g.,
```
(std::unique_ptr<int>) iup = 0x55555556d2b0 {
pointer = 0x000055555556d2b0
}
(std::unique_ptr<std::basic_string<char> >) sup = 0x55555556d2d0 {
pointer = "foobar"
}
```
This patch moves the logic into a common helper that's shared between
the libc++ and libstdc++ formatters.
---
.../lldb/DataFormatters/FormattersHelpers.h | 6 +++
.../DataFormatters/FormattersHelpers.cpp | 22 +++++++++++
.../Plugins/Language/CPlusPlus/LibCxx.cpp | 37 +------------------
.../CPlusPlus/LibStdcppUniquePointer.cpp | 10 +----
.../TestDataFormatterStdUniquePtr.py | 14 +++----
5 files changed, 39 insertions(+), 50 deletions(-)
diff --git a/lldb/include/lldb/DataFormatters/FormattersHelpers.h b/lldb/include/lldb/DataFormatters/FormattersHelpers.h
index 42699d0a0b1b1..ea77b43e8da39 100644
--- a/lldb/include/lldb/DataFormatters/FormattersHelpers.h
+++ b/lldb/include/lldb/DataFormatters/FormattersHelpers.h
@@ -55,6 +55,12 @@ void AddFilter(TypeCategoryImpl::SharedPointer category_sp,
std::optional<size_t> ExtractIndexFromString(const char *item_name);
+/// Returns \c false if the smart pointer formatters shouldn't continue
+/// formatting the rest of the object. Currently this is the case when the
+/// pointer is a nullptr.
+bool DumpCxxSmartPtrPointerSummary(Stream &stream, ValueObject &ptr,
+ const TypeSummaryOptions &options);
+
Address GetArrayAddressOrPointerValue(ValueObject &valobj);
time_t GetOSXEpoch();
diff --git a/lldb/source/DataFormatters/FormattersHelpers.cpp b/lldb/source/DataFormatters/FormattersHelpers.cpp
index d7b058d91c4a3..022a5d12efae3 100644
--- a/lldb/source/DataFormatters/FormattersHelpers.cpp
+++ b/lldb/source/DataFormatters/FormattersHelpers.cpp
@@ -126,3 +126,25 @@ lldb_private::formatters::GetArrayAddressOrPointerValue(ValueObject &valobj) {
return data_addr.address;
}
+
+bool lldb_private::formatters::DumpCxxSmartPtrPointerSummary(
+ Stream &stream, ValueObject &ptr, const TypeSummaryOptions &options) {
+ if (ptr.GetValueAsUnsigned(0) == 0) {
+ stream.Printf("nullptr");
+ return true;
+ }
+
+ Status error;
+ ValueObjectSP pointee_sp = ptr.Dereference(error);
+ // FIXME: should we be handling this as an error?
+ if (!pointee_sp || !error.Success())
+ return false;
+
+ if (!pointee_sp->DumpPrintableRepresentation(
+ stream, ValueObject::eValueObjectRepresentationStyleSummary,
+ lldb::eFormatInvalid,
+ ValueObject::PrintableRepresentationSpecialCases::eDisable, false))
+ stream.Printf("ptr = 0x%" PRIx64, ptr.GetValueAsUnsigned(0));
+
+ return false;
+}
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
index 7143089209dd3..995c943ac4da4 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
@@ -166,24 +166,8 @@ bool lldb_private::formatters::LibcxxSmartPointerSummaryProvider(
if (!ptr_sp)
return false;
- if (ptr_sp->GetValueAsUnsigned(0) == 0) {
- stream.Printf("nullptr");
+ if (!DumpCxxSmartPtrPointerSummary(stream, *ptr_sp, options))
return true;
- } else {
- bool print_pointee = false;
- 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))
- print_pointee = true;
- }
- if (!print_pointee)
- stream.Printf("ptr = 0x%" PRIx64, ptr_sp->GetValueAsUnsigned(0));
- }
if (count_sp)
stream.Printf(" strong=%" PRIu64, 1 + count_sp->GetValueAsUnsigned(0));
@@ -210,24 +194,7 @@ bool lldb_private::formatters::LibcxxUniquePointerSummaryProvider(
if (!ptr_sp)
return false;
- if (ptr_sp->GetValueAsUnsigned(0) == 0) {
- stream.Printf("nullptr");
- return true;
- } else {
- bool print_pointee = false;
- 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))
- print_pointee = true;
- }
- if (!print_pointee)
- stream.Printf("ptr = 0x%" PRIx64, ptr_sp->GetValueAsUnsigned(0));
- }
+ DumpCxxSmartPtrPointerSummary(stream, *ptr_sp, options);
return true;
}
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibStdcppUniquePointer.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibStdcppUniquePointer.cpp
index b47ff579b6a5e..e570a4bb1a886 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibStdcppUniquePointer.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibStdcppUniquePointer.cpp
@@ -156,14 +156,8 @@ bool LibStdcppUniquePtrSyntheticFrontEnd::GetSummary(
if (!m_ptr_obj)
return false;
- bool success;
- uint64_t ptr_value = m_ptr_obj->GetValueAsUnsigned(0, &success);
- if (!success)
- return false;
- if (ptr_value == 0)
- stream.Printf("nullptr");
- else
- stream.Printf("0x%" PRIx64, ptr_value);
+ DumpCxxSmartPtrPointerSummary(stream, *m_ptr_obj, options);
+
return true;
}
diff --git a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py
index 2301e5edfbd90..600a8669c81ba 100644
--- a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py
+++ b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py
@@ -31,15 +31,15 @@ def test_with_run_command(self):
self.assertTrue(frame.IsValid())
self.expect("frame variable nup", substrs=["nup = nullptr"])
- self.expect("frame variable iup", substrs=["iup = 0x"])
- self.expect("frame variable sup", substrs=["sup = 0x"])
+ self.expect("frame variable iup", substrs=["iup = 123"])
+ self.expect("frame variable sup", substrs=['sup = "foobar"'])
self.expect("frame variable ndp", substrs=["ndp = nullptr"])
self.expect(
- "frame variable idp", substrs=["idp = 0x", "deleter = ", "a = 1", "b = 2"]
+ "frame variable idp", substrs=["idp = 456", "deleter = ", "a = 1", "b = 2"]
)
self.expect(
- "frame variable sdp", substrs=["sdp = 0x", "deleter = ", "a = 3", "b = 4"]
+ "frame variable sdp", substrs=['sdp = "baz"', "deleter = ", "a = 3", "b = 4"]
)
self.assertEqual(
@@ -106,13 +106,13 @@ def test_recursive_unique_ptr(self):
substrs=["stopped", "stop reason = breakpoint"],
)
- self.expect("frame variable f1->fp", substrs=["fp = 0x"])
+ self.expect("frame variable f1->fp", substrs=["fp = Foo @ 0x"])
self.expect(
- "frame variable --ptr-depth=1 f1->fp", substrs=["data = 2", "fp = 0x"]
+ "frame variable --ptr-depth=1 f1->fp", substrs=["data = 2", "fp = Foo @ 0x"]
)
self.expect(
"frame variable --ptr-depth=2 f1->fp",
- substrs=["data = 2", "fp = 0x", "data = 1"],
+ substrs=["data = 2", "fp = Foo @ 0x", "data = 1"],
)
frame = self.frame()
>From 63066cc6e1f940f38728ab722ef8a0c72e6c8215 Mon Sep 17 00:00:00 2001
From: Michael Buch <michaelbuch12 at gmail.com>
Date: Thu, 3 Jul 2025 15:49:52 +0100
Subject: [PATCH 2/4] fixup! python format
---
.../libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py
index 600a8669c81ba..8f57dc88f3187 100644
--- a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py
+++ b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/unique_ptr/TestDataFormatterStdUniquePtr.py
@@ -2,7 +2,6 @@
Test lldb data formatter subsystem.
"""
-
import lldb
from lldbsuite.test.decorators import *
from lldbsuite.test.lldbtest import *
@@ -39,7 +38,8 @@ def test_with_run_command(self):
"frame variable idp", substrs=["idp = 456", "deleter = ", "a = 1", "b = 2"]
)
self.expect(
- "frame variable sdp", substrs=['sdp = "baz"', "deleter = ", "a = 3", "b = 4"]
+ "frame variable sdp",
+ substrs=['sdp = "baz"', "deleter = ", "a = 3", "b = 4"],
)
self.assertEqual(
>From 84de12d24c7862542a7fe91b47c2721b65a1e968 Mon Sep 17 00:00:00 2001
From: Michael Buch <michaelbuch12 at gmail.com>
Date: Thu, 3 Jul 2025 17:18:04 +0100
Subject: [PATCH 3/4] fixup! remove early-return for empty shared_ptrs;
refactor weak/strong count printing
---
.../lldb/DataFormatters/FormattersHelpers.h | 7 ++--
.../DataFormatters/FormattersHelpers.cpp | 9 ++---
.../Plugins/Language/CPlusPlus/LibCxx.cpp | 37 +++++++++++++------
.../TestDataFormatterLibcxxSharedPtr.py | 14 +++++++
.../libcxx/shared_ptr/main.cpp | 4 ++
5 files changed, 50 insertions(+), 21 deletions(-)
diff --git a/lldb/include/lldb/DataFormatters/FormattersHelpers.h b/lldb/include/lldb/DataFormatters/FormattersHelpers.h
index ea77b43e8da39..97d367afc65d7 100644
--- a/lldb/include/lldb/DataFormatters/FormattersHelpers.h
+++ b/lldb/include/lldb/DataFormatters/FormattersHelpers.h
@@ -55,10 +55,9 @@ void AddFilter(TypeCategoryImpl::SharedPointer category_sp,
std::optional<size_t> ExtractIndexFromString(const char *item_name);
-/// Returns \c false if the smart pointer formatters shouldn't continue
-/// formatting the rest of the object. Currently this is the case when the
-/// pointer is a nullptr.
-bool DumpCxxSmartPtrPointerSummary(Stream &stream, ValueObject &ptr,
+/// Prints the summary for the pointer value of a C++
+/// std::unique_ptr/std::shared_ptr/std::weak_ptr.
+void DumpCxxSmartPtrPointerSummary(Stream &stream, ValueObject &ptr,
const TypeSummaryOptions &options);
Address GetArrayAddressOrPointerValue(ValueObject &valobj);
diff --git a/lldb/source/DataFormatters/FormattersHelpers.cpp b/lldb/source/DataFormatters/FormattersHelpers.cpp
index 022a5d12efae3..81c76b06fc47a 100644
--- a/lldb/source/DataFormatters/FormattersHelpers.cpp
+++ b/lldb/source/DataFormatters/FormattersHelpers.cpp
@@ -127,24 +127,21 @@ lldb_private::formatters::GetArrayAddressOrPointerValue(ValueObject &valobj) {
return data_addr.address;
}
-bool lldb_private::formatters::DumpCxxSmartPtrPointerSummary(
+void lldb_private::formatters::DumpCxxSmartPtrPointerSummary(
Stream &stream, ValueObject &ptr, const TypeSummaryOptions &options) {
if (ptr.GetValueAsUnsigned(0) == 0) {
stream.Printf("nullptr");
- return true;
+ return;
}
Status error;
ValueObjectSP pointee_sp = ptr.Dereference(error);
- // FIXME: should we be handling this as an error?
if (!pointee_sp || !error.Success())
- return false;
+ return;
if (!pointee_sp->DumpPrintableRepresentation(
stream, ValueObject::eValueObjectRepresentationStyleSummary,
lldb::eFormatInvalid,
ValueObject::PrintableRepresentationSpecialCases::eDisable, false))
stream.Printf("ptr = 0x%" PRIx64, ptr.GetValueAsUnsigned(0));
-
- return false;
}
diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
index 995c943ac4da4..009586f525282 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
@@ -157,23 +157,38 @@ bool lldb_private::formatters::LibcxxSmartPointerSummaryProvider(
ValueObjectSP valobj_sp(valobj.GetNonSyntheticValue());
if (!valobj_sp)
return false;
- ValueObjectSP ptr_sp(valobj_sp->GetChildMemberWithName("__ptr_"));
- ValueObjectSP count_sp(
- valobj_sp->GetChildAtNamePath({"__cntrl_", "__shared_owners_"}));
- ValueObjectSP weakcount_sp(
- valobj_sp->GetChildAtNamePath({"__cntrl_", "__shared_weak_owners_"}));
- if (!ptr_sp)
+ ValueObjectSP ptr_sp(valobj_sp->GetChildMemberWithName("__ptr_"));
+ ValueObjectSP ctrl_sp(valobj_sp->GetChildMemberWithName("__cntrl_"));
+ if (!ctrl_sp || !ptr_sp)
return false;
- if (!DumpCxxSmartPtrPointerSummary(stream, *ptr_sp, options))
+ DumpCxxSmartPtrPointerSummary(stream, *ptr_sp, options);
+
+ bool success;
+ uint64_t ctrl_addr = ctrl_sp->GetValueAsUnsigned(0, &success);
+ // Empty control field. We're done.
+ if (!success || ctrl_addr == 0)
return true;
- if (count_sp)
- stream.Printf(" strong=%" PRIu64, 1 + count_sp->GetValueAsUnsigned(0));
+ if (auto count_sp = ctrl_sp->GetChildMemberWithName("__shared_owners_")) {
+ bool success;
+ uint64_t count = count_sp->GetValueAsUnsigned(0, &success);
+ if (!success)
+ return false;
+
+ stream.Printf(" strong=%" PRIu64, count + 1);
+ }
- if (weakcount_sp)
- stream.Printf(" weak=%" PRIu64, 1 + weakcount_sp->GetValueAsUnsigned(0));
+ if (auto weak_count_sp =
+ ctrl_sp->GetChildMemberWithName("__shared_weak_owners_")) {
+ bool success;
+ uint64_t count = weak_count_sp->GetValueAsUnsigned(0, &success);
+ if (!success)
+ return false;
+
+ stream.Printf(" weak=%" PRIu64, count + 1);
+ }
return true;
}
diff --git a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py
index 61c050b3bfa01..cc3bffca8307a 100644
--- a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py
+++ b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py
@@ -91,6 +91,20 @@ def test_shared_ptr_variables(self):
self.expect_var_path("sp_user->id", type="int", value="30")
self.expect_var_path("sp_user->name", type="std::string", summary='"steph"')
+ #valobj = self.expect_var_path(
+ # "si",
+ # type="std::shared_ptr<int> &",
+ # children=[ValueCheck(name="__ptr_")],
+ #)
+ #self.assertRegex(valobj.summary, r"^10( strong=1)? weak=1$")
+
+ #valobj = self.expect_var_path(
+ # "sie",
+ # type="std::shared_ptr<int> &",
+ # children=[ValueCheck(name="__ptr_")],
+ #)
+ #self.assertRegex(valobj.summary, r"^10( strong=1)? weak=1$")
+
self.runCmd("settings set target.experimental.use-DIL true")
self.expect_var_path("ptr_node->value", value="1")
self.expect_var_path("ptr_node->next->value", value="2")
diff --git a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/main.cpp b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/main.cpp
index 84a02ec13df1c..3ac86a3ee9843 100644
--- a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/main.cpp
+++ b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/main.cpp
@@ -22,5 +22,9 @@ int main() {
std::shared_ptr<NodeS>(new NodeS{nullptr, 2});
ptr_node = std::shared_ptr<NodeS>(new NodeS{std::move(ptr_node), 1});
+ // Construct empty shared_ptr with non-null control field.
+ std::shared_ptr<int> si(new int(47));
+ std::shared_ptr<int> sie(si, nullptr);
+
return 0; // break here
}
>From bd20056c0e7523a4fdc9bb14af172b12a7758cc0 Mon Sep 17 00:00:00 2001
From: Michael Buch <michaelbuch12 at gmail.com>
Date: Thu, 3 Jul 2025 17:29:28 +0100
Subject: [PATCH 4/4] fixup! uncomment subobject constructor test
---
.../TestDataFormatterLibcxxSharedPtr.py | 24 +++++++++----------
1 file changed, 11 insertions(+), 13 deletions(-)
diff --git a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py
index cc3bffca8307a..c124011427a8a 100644
--- a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py
+++ b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/shared_ptr/TestDataFormatterLibcxxSharedPtr.py
@@ -91,19 +91,17 @@ def test_shared_ptr_variables(self):
self.expect_var_path("sp_user->id", type="int", value="30")
self.expect_var_path("sp_user->name", type="std::string", summary='"steph"')
- #valobj = self.expect_var_path(
- # "si",
- # type="std::shared_ptr<int> &",
- # children=[ValueCheck(name="__ptr_")],
- #)
- #self.assertRegex(valobj.summary, r"^10( strong=1)? weak=1$")
-
- #valobj = self.expect_var_path(
- # "sie",
- # type="std::shared_ptr<int> &",
- # children=[ValueCheck(name="__ptr_")],
- #)
- #self.assertRegex(valobj.summary, r"^10( strong=1)? weak=1$")
+ valobj = self.expect_var_path(
+ "si",
+ type="std::shared_ptr<int>",
+ summary="47 strong=2 weak=1"
+ )
+
+ valobj = self.expect_var_path(
+ "sie",
+ type="std::shared_ptr<int>",
+ summary="nullptr strong=2 weak=1"
+ )
self.runCmd("settings set target.experimental.use-DIL true")
self.expect_var_path("ptr_node->value", value="1")
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