[Lldb-commits] [lldb] [LLDB] Don't ignore artificial variables and members for coroutines (PR #70779)

[Haojian Wu via lldb-commits]

https://github.com/hokein updated https://github.com/llvm/llvm-project/pull/70779

>From 4cc40aafef4db5133f4360b2fb367e1776dc2901 Mon Sep 17 00:00:00 2001
From: Haojian Wu <hokein.wu at gmail.com>
Date: Tue, 31 Oct 2023 11:15:45 +0100
Subject: [PATCH 1/2] [LLDB] Don't ignore artificial variables and members for
 coroutines

* always populate all fields for the generated coroutine frame type;
* make the artificial variables `__promise`, `__coro_frame` visible, so
  that they are present in the `frame var` command;
---
 .../Plugins/LanguageRuntime/CPlusPlus/CPPLanguageRuntime.cpp | 5 ++++-
 lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp | 3 ++-
 lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp     | 4 ++++
 lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h       | 3 +++
 4 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/lldb/source/Plugins/LanguageRuntime/CPlusPlus/CPPLanguageRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/CPlusPlus/CPPLanguageRuntime.cpp
index c2488eaa9f5b50d..c7d9eb37f9b5199 100644
--- a/lldb/source/Plugins/LanguageRuntime/CPlusPlus/CPPLanguageRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/CPlusPlus/CPPLanguageRuntime.cpp
@@ -41,7 +41,10 @@ CPPLanguageRuntime::CPPLanguageRuntime(Process *process)
     : LanguageRuntime(process) {}
 
 bool CPPLanguageRuntime::IsAllowedRuntimeValue(ConstString name) {
-  return name == g_this;
+  // FIXME: use a list when the list grows more.
+  return name == g_this ||
+         name == ConstString("__promise") ||
+         name == ConstString("__coro_frame");
 }
 
 bool CPPLanguageRuntime::GetObjectDescription(Stream &str,
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
index 182cc6764651747..d2708d183801035 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
@@ -3061,7 +3061,8 @@ void DWARFASTParserClang::ParseSingleMember(
   // artificial member with (unnamed bitfield) padding.
   // FIXME: This check should verify that this is indeed an artificial member
   // we are supposed to ignore.
-  if (attrs.is_artificial) {
+  if (attrs.is_artificial &&
+      !TypeSystemClang::IsCoroutineFrameType(class_clang_type)) {
     last_field_info.SetIsArtificial(true);
     return;
   }
diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
index f037708efc38007..138f5531db2a9fb 100644
--- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
+++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
@@ -771,6 +771,10 @@ TypeSystemClang *TypeSystemClang::GetASTContext(clang::ASTContext *ast) {
   return clang_ast;
 }
 
+bool TypeSystemClang::IsCoroutineFrameType(const CompilerType &Type) {
+  return Type.GetTypeName().GetStringRef().ends_with(".coro_frame_ty");
+}
+
 clang::MangleContext *TypeSystemClang::getMangleContext() {
   if (m_mangle_ctx_up == nullptr)
     m_mangle_ctx_up.reset(getASTContext().createMangleContext());
diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
index 0ec2d026e996105..6168a065eb522e9 100644
--- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
+++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
@@ -154,6 +154,9 @@ class TypeSystemClang : public TypeSystem {
 
   static TypeSystemClang *GetASTContext(clang::ASTContext *ast_ctx);
 
+  // Returns true if the given type is a coroutine frame debug type.
+  static bool IsCoroutineFrameType(const CompilerType &Type);
+
   /// Returns the display name of this TypeSystemClang that indicates what
   /// purpose it serves in LLDB. Used for example in logs.
   llvm::StringRef getDisplayName() const { return m_display_name; }

>From c145045251683c42008dff49e2f02cf0a8020894 Mon Sep 17 00:00:00 2001
From: Haojian Wu <hokein.wu at gmail.com>
Date: Fri, 3 Nov 2023 12:07:23 +0100
Subject: [PATCH 2/2] Add and use `ShouldIgnoreArtificialField` API to ignore
 the indeed artificial members we should ignore.

---
 lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp | 4 +---
 lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp     | 4 ++--
 lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h       | 5 +++--
 3 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
index d2708d183801035..0c0566eec56133f 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
@@ -3059,10 +3059,8 @@ void DWARFASTParserClang::ParseSingleMember(
   // This needs to be done after updating FieldInfo which keeps track of where
   // field start/end so we don't later try to fill the space of this
   // artificial member with (unnamed bitfield) padding.
-  // FIXME: This check should verify that this is indeed an artificial member
-  // we are supposed to ignore.
   if (attrs.is_artificial &&
-      !TypeSystemClang::IsCoroutineFrameType(class_clang_type)) {
+      TypeSystemClang::ShouldIgnoreArtificialField(attrs.name)) {
     last_field_info.SetIsArtificial(true);
     return;
   }
diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
index 138f5531db2a9fb..e947e99074a7542 100644
--- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
+++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
@@ -771,8 +771,8 @@ TypeSystemClang *TypeSystemClang::GetASTContext(clang::ASTContext *ast) {
   return clang_ast;
 }
 
-bool TypeSystemClang::IsCoroutineFrameType(const CompilerType &Type) {
-  return Type.GetTypeName().GetStringRef().ends_with(".coro_frame_ty");
+bool TypeSystemClang::ShouldIgnoreArtificialField(llvm::StringRef Name) {
+  return Name.starts_with("_vptr$");
 }
 
 clang::MangleContext *TypeSystemClang::getMangleContext() {
diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
index 6168a065eb522e9..477b655bb7c86ea 100644
--- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
+++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
@@ -154,8 +154,9 @@ class TypeSystemClang : public TypeSystem {
 
   static TypeSystemClang *GetASTContext(clang::ASTContext *ast_ctx);
 
-  // Returns true if the given type is a coroutine frame debug type.
-  static bool IsCoroutineFrameType(const CompilerType &Type);
+  // Returns true if the given artificial field name should be ignored when
+  // parsing the DWARF.
+  static bool ShouldIgnoreArtificialField(llvm::StringRef FieldName);
 
   /// Returns the display name of this TypeSystemClang that indicates what
   /// purpose it serves in LLDB. Used for example in logs.