[lldb] Centralize desugaring of decltype-like types in ClangASTContext

Summary:
These types were handled in some places, but not others. This resulted
in (for example) not being able to display members of structs whose
types were defined using these constructs.

Using getLocallyUnqualifiedSingleStepDesugaredType for these types is
not fully equivalent, as it will only desugar them if the types are not
instantiation-dependent, whereas previously we did that unconditionally.

It's not clear to me which behavior is correct here, but the test suite
does not seem to care either way.

Reviewers: teemperor, shafik

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71405

1 files changed, 12 insertions, 74 deletions

diff --git a/lldb/source/Symbol/ClangASTContext.cpp b/lldb/source/Symbol/ClangASTContext.cpp
index ed613528a2f..95bb4551f2c 100644
--- a/lldb/source/Symbol/ClangASTContext.cpp
+++ b/lldb/source/Symbol/ClangASTContext.cpp
@@ -2499,9 +2499,12 @@ RemoveWrappingTypes(QualType type, ArrayRef<clang::Type::TypeClass> mask = {}) {
       type = cast<clang::AtomicType>(type)->getValueType();
       break;
     case clang::Type::Auto:
+    case clang::Type::Decltype:
     case clang::Type::Elaborated:
     case clang::Type::Paren:
     case clang::Type::Typedef:
+    case clang::Type::TypeOf:
+    case clang::Type::TypeOfExpr:
       type = type->getLocallyUnqualifiedSingleStepDesugaredType();
       break;
     default:
@@ -3765,11 +3768,6 @@ ClangASTContext::GetTypeInfo(lldb::opaque_compiler_type_t type,
     return eTypeHasChildren | eTypeIsVector;
   case clang::Type::DependentTemplateSpecialization:
     return eTypeIsTemplate;
-  case clang::Type::Decltype:
-    return CompilerType(this, llvm::cast<clang::DecltypeType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetTypeInfo(pointee_or_element_clang_type);
 
   case clang::Type::Enum:
     if (pointee_or_element_clang_type)
@@ -3837,17 +3835,6 @@ ClangASTContext::GetTypeInfo(lldb::opaque_compiler_type_t type,
                                   ->getUnderlyingType()
                                   .getAsOpaquePtr())
                .GetTypeInfo(pointee_or_element_clang_type);
-  case clang::Type::TypeOfExpr:
-    return CompilerType(this, llvm::cast<clang::TypeOfExprType>(qual_type)
-                                  ->getUnderlyingExpr()
-                                  ->getType()
-                                  .getAsOpaquePtr())
-        .GetTypeInfo(pointee_or_element_clang_type);
-  case clang::Type::TypeOf:
-    return CompilerType(this, llvm::cast<clang::TypeOfType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetTypeInfo(pointee_or_element_clang_type);
   case clang::Type::UnresolvedUsing:
     return 0;
 
@@ -3966,8 +3953,11 @@ ClangASTContext::GetTypeClass(lldb::opaque_compiler_type_t type) {
   switch (qual_type->getTypeClass()) {
   case clang::Type::Atomic:
   case clang::Type::Auto:
+  case clang::Type::Decltype:
   case clang::Type::Elaborated:
   case clang::Type::Paren:
+  case clang::Type::TypeOf:
+  case clang::Type::TypeOfExpr:
     llvm_unreachable("Handled in RemoveWrappingTypes!");
   case clang::Type::UnaryTransform:
     break;
@@ -4049,22 +4039,6 @@ ClangASTContext::GetTypeClass(lldb::opaque_compiler_type_t type) {
   case clang::Type::PackExpansion:
     break;
 
-  case clang::Type::TypeOfExpr:
-    return CompilerType(this, llvm::cast<clang::TypeOfExprType>(qual_type)
-                                  ->getUnderlyingExpr()
-                                  ->getType()
-                                  .getAsOpaquePtr())
-        .GetTypeClass();
-  case clang::Type::TypeOf:
-    return CompilerType(this, llvm::cast<clang::TypeOfType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetTypeClass();
-  case clang::Type::Decltype:
-    return CompilerType(this, llvm::cast<clang::TypeOfType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetTypeClass();
   case clang::Type::TemplateSpecialization:
     break;
   case clang::Type::DeducedTemplateSpecialization:
@@ -4678,9 +4652,12 @@ lldb::Encoding ClangASTContext::GetEncoding(lldb::opaque_compiler_type_t type,
   switch (qual_type->getTypeClass()) {
   case clang::Type::Atomic:
   case clang::Type::Auto:
+  case clang::Type::Decltype:
   case clang::Type::Elaborated:
   case clang::Type::Paren:
   case clang::Type::Typedef:
+  case clang::Type::TypeOf:
+  case clang::Type::TypeOfExpr:
     llvm_unreachable("Handled in RemoveWrappingTypes!");
 
   case clang::Type::UnaryTransform:
@@ -4888,22 +4865,6 @@ lldb::Encoding ClangASTContext::GetEncoding(lldb::opaque_compiler_type_t type,
     break;
   case clang::Type::Enum:
     return lldb::eEncodingSint;
-  case clang::Type::TypeOfExpr:
-    return CompilerType(this, llvm::cast<clang::TypeOfExprType>(qual_type)
-                                  ->getUnderlyingExpr()
-                                  ->getType()
-                                  .getAsOpaquePtr())
-        .GetEncoding(count);
-  case clang::Type::TypeOf:
-    return CompilerType(this, llvm::cast<clang::TypeOfType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetEncoding(count);
-  case clang::Type::Decltype:
-    return CompilerType(this, llvm::cast<clang::DecltypeType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetEncoding(count);
   case clang::Type::DependentSizedArray:
   case clang::Type::DependentSizedExtVector:
   case clang::Type::UnresolvedUsing:
@@ -4947,9 +4908,12 @@ lldb::Format ClangASTContext::GetFormat(lldb::opaque_compiler_type_t type) {
   switch (qual_type->getTypeClass()) {
   case clang::Type::Atomic:
   case clang::Type::Auto:
+  case clang::Type::Decltype:
   case clang::Type::Elaborated:
   case clang::Type::Paren:
   case clang::Type::Typedef:
+  case clang::Type::TypeOf:
+  case clang::Type::TypeOfExpr:
     llvm_unreachable("Handled in RemoveWrappingTypes!");
   case clang::Type::UnaryTransform:
     break;
@@ -5043,22 +5007,6 @@ lldb::Format ClangASTContext::GetFormat(lldb::opaque_compiler_type_t type) {
     break;
   case clang::Type::Enum:
     return lldb::eFormatEnum;
-  case clang::Type::TypeOfExpr:
-    return CompilerType(this, llvm::cast<clang::TypeOfExprType>(qual_type)
-                                  ->getUnderlyingExpr()
-                                  ->getType()
-                                  .getAsOpaquePtr())
-        .GetFormat();
-  case clang::Type::TypeOf:
-    return CompilerType(this, llvm::cast<clang::TypeOfType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetFormat();
-  case clang::Type::Decltype:
-    return CompilerType(this, llvm::cast<clang::DecltypeType>(qual_type)
-                                  ->getUnderlyingType()
-                                  .getAsOpaquePtr())
-        .GetFormat();
   case clang::Type::DependentSizedArray:
   case clang::Type::DependentSizedExtVector:
   case clang::Type::UnresolvedUsing:
@@ -5930,16 +5878,6 @@ uint32_t ClangASTContext::GetNumPointeeChildren(clang::QualType type) {
     return 0; // When we function pointers, they have no children...
   case clang::Type::UnresolvedUsing:
     return 0;
-  case clang::Type::TypeOfExpr:
-    return GetNumPointeeChildren(llvm::cast<clang::TypeOfExprType>(qual_type)
-                                     ->getUnderlyingExpr()
-                                     ->getType());
-  case clang::Type::TypeOf:
-    return GetNumPointeeChildren(
-        llvm::cast<clang::TypeOfType>(qual_type)->getUnderlyingType());
-  case clang::Type::Decltype:
-    return GetNumPointeeChildren(
-        llvm::cast<clang::DecltypeType>(qual_type)->getUnderlyingType());
   case clang::Type::Record:
     return 0;
   case clang::Type::Enum: