Merge pull request #9975 from augusto2112/fix-gen-local-buffer

[lldb] Make GetDynamicTypeAndAddress() use host address if available

Author: augusto2112

lldb/include/lldb/Target/LanguageRuntime.h

@@ -106,12 +106,16 @@ class LanguageRuntime : public Runtime, public PluginInterface {
         "language doesn't support getting vtable information");
   }
 
-  // this call should return true if it could set the name and/or the type
-  virtual bool GetDynamicTypeAndAddress(ValueObject &in_value,
-                                        lldb::DynamicValueType use_dynamic,
-                                        TypeAndOrName &class_type_or_name,
-                                        Address &address,
-                                        Value::ValueType &value_type) = 0;
+  /// This call should return true if it could set the name and/or the type
+  /// Sets address to the address of the dynamic type if value_type is set to
+  /// a file or load address. Sets local_buffer to a buffer containing the data
+  /// of the dynamic type if value_type is set to a host address. Callers should
+  /// copy local_buffer over into their own buffer if they want to keep the data
+  /// alive.
+  virtual bool GetDynamicTypeAndAddress(
+      ValueObject &in_value, lldb::DynamicValueType use_dynamic,
+      TypeAndOrName &class_type_or_name, Address &address,
+      Value::ValueType &value_type, llvm::ArrayRef<uint8_t> &local_buffer) = 0;
 
   // This call should return a CompilerType given a generic type name and an
   // ExecutionContextScope in which one can actually fetch any specialization

lldb/include/lldb/ValueObject/ValueObject.h

@@ -869,6 +869,19 @@ class ValueObject {
 
   virtual void SetLanguageFlags(uint64_t flags) { m_language_flags = flags; }
 
+  /// Returns the local buffer that this ValueObject points to if it's
+  /// available.
+  /// \return
+  ///     The local buffer if this value object's value points to a
+  ///     host address, and if that buffer can be determined. Otherwise, returns
+  ///     an empty ArrayRef.
+  ///
+  /// TODO: Because a ValueObject's Value can point to any arbitrary memory
+  /// location, it is possible that we can't find what what buffer we're
+  /// pointing to, and thus also can't know its size. See the comment in
+  /// Value::m_value for a more thorough explanation of why that is.
+  llvm::ArrayRef<uint8_t> GetLocalBuffer() const;
+
 protected:
   typedef ClusterManager<ValueObject> ValueObjectManager;
 

lldb/source/Plugins/Language/Swift/SwiftLanguage.cpp

@@ -1114,13 +1114,14 @@ SwiftLanguage::GetHardcodedSynthetics() {
       TypeAndOrName type_or_name;
       Address address;
       Value::ValueType value_type;
+      llvm::ArrayRef<uint8_t> local_buffer;
       // Try to find the dynamic type of the Swift type.
       // TODO: find a way to get the dyamic value type from the
       // command.
       if (swift_runtime->GetDynamicTypeAndAddress(
               *casted_to_swift.get(),
               lldb::DynamicValueType::eDynamicCanRunTarget, type_or_name,
-              address, value_type)) {
+              address, value_type, local_buffer)) {
         if (type_or_name.HasCompilerType()) {
           swift_type = type_or_name.GetCompilerType();
           // Cast it to the more specific type.
@@ -1248,8 +1249,9 @@ SwiftLanguage::GetPossibleFormattersMatches(
   TypeAndOrName type_and_or_name;
   Address address;
   Value::ValueType value_type;
+  llvm::ArrayRef<uint8_t> local_buffer;
   if (!runtime->GetDynamicTypeAndAddress(valobj, use_dynamic, type_and_or_name,
-                                         address, value_type))
+                                         address, value_type, local_buffer))
     return result;
   if (ConstString name = type_and_or_name.GetName())
     result.push_back(

lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp

@@ -288,7 +288,7 @@ llvm::Expected<LanguageRuntime::VTableInfo>
 bool ItaniumABILanguageRuntime::GetDynamicTypeAndAddress(
     ValueObject &in_value, lldb::DynamicValueType use_dynamic,
     TypeAndOrName &class_type_or_name, Address &dynamic_address,
-    Value::ValueType &value_type) {
+    Value::ValueType &value_type, llvm::ArrayRef<uint8_t> &local_buffer) {
   // For Itanium, if the type has a vtable pointer in the object, it will be at
   // offset 0 in the object.  That will point to the "address point" within the
   // vtable (not the beginning of the vtable.)  We can then look up the symbol

lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h

@@ -54,8 +54,8 @@ class ItaniumABILanguageRuntime : public lldb_private::CPPLanguageRuntime {
   bool GetDynamicTypeAndAddress(ValueObject &in_value,
                                 lldb::DynamicValueType use_dynamic,
                                 TypeAndOrName &class_type_or_name,
-                                Address &address,
-                                Value::ValueType &value_type) override;
+                                Address &address, Value::ValueType &value_type,
+                                llvm::ArrayRef<uint8_t> &local_buffer) override;
 
   TypeAndOrName FixUpDynamicType(const TypeAndOrName &type_and_or_name,
                                  ValueObject &static_value) override;

lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp

@@ -276,7 +276,7 @@ bool AppleObjCRuntime::CouldHaveDynamicValue(ValueObject &in_value) {
 bool AppleObjCRuntime::GetDynamicTypeAndAddress(
     ValueObject &in_value, lldb::DynamicValueType use_dynamic,
     TypeAndOrName &class_type_or_name, Address &address,
-    Value::ValueType &value_type) {
+    Value::ValueType &value_type, llvm::ArrayRef<uint8_t> &local_buffer) {
   return false;
 }
 

lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h

@@ -54,8 +54,8 @@ class AppleObjCRuntime : public lldb_private::ObjCLanguageRuntime {
   bool GetDynamicTypeAndAddress(ValueObject &in_value,
                                 lldb::DynamicValueType use_dynamic,
                                 TypeAndOrName &class_type_or_name,
-                                Address &address,
-                                Value::ValueType &value_type) override;
+                                Address &address, Value::ValueType &value_type,
+                                llvm::ArrayRef<uint8_t> &local_buffer) override;
 
   TypeAndOrName FixUpDynamicType(const TypeAndOrName &type_and_or_name,
                                  ValueObject &static_value) override;

lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp

@@ -48,7 +48,7 @@ AppleObjCRuntimeV1::AppleObjCRuntimeV1(Process *process)
 bool AppleObjCRuntimeV1::GetDynamicTypeAndAddress(
     ValueObject &in_value, lldb::DynamicValueType use_dynamic,
     TypeAndOrName &class_type_or_name, Address &address,
-    Value::ValueType &value_type) {
+    Value::ValueType &value_type, llvm::ArrayRef<uint8_t> &local_buffer) {
   class_type_or_name.Clear();
   value_type = Value::ValueType::Scalar;
   if (CouldHaveDynamicValue(in_value)) {

lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h

@@ -100,8 +100,8 @@ class AppleObjCRuntimeV1 : public AppleObjCRuntime {
   bool GetDynamicTypeAndAddress(ValueObject &in_value,
                                 lldb::DynamicValueType use_dynamic,
                                 TypeAndOrName &class_type_or_name,
-                                Address &address,
-                                Value::ValueType &value_type) override;
+                                Address &address, Value::ValueType &value_type,
+                                llvm::ArrayRef<uint8_t> &local_buffer) override;
 
   llvm::Expected<std::unique_ptr<UtilityFunction>>
   CreateObjectChecker(std::string, ExecutionContext &exe_ctx) override;

lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp

@@ -775,7 +775,7 @@ AppleObjCRuntimeV2::GetPreferredLanguageRuntime(ValueObject &in_value) {
 bool AppleObjCRuntimeV2::GetDynamicTypeAndAddress(
     ValueObject &in_value, lldb::DynamicValueType use_dynamic,
     TypeAndOrName &class_type_or_name, Address &address,
-    Value::ValueType &value_type) {
+    Value::ValueType &value_type, llvm::ArrayRef<uint8_t> &local_buffer) {
   // We should never get here with a null process...
   assert(m_process != nullptr);