Allow LanguageRuntimes to return an error if they fail in the course of dynamic type discovery

This is not meant to report that a value doesn't have a dynamic type - it is only meant as a mechanism to propagate actual type discovery issues (e.g. malformed type metadata for languages that have such a notion)

This information is used by ValueObjectDynamic to set its own m_error, which is a fairly sharp and heavyweight tool to begin with

For the time being, this is an architectural improvement but a practical no-op as no existing runtimes are actually setting errors

llvm-svn: 268591

16 files changed, 98 insertions, 38 deletions

diff --git a/lldb/include/lldb/Target/LanguageRuntime.h b/lldb/include/lldb/Target/LanguageRuntime.h
index 20473e3b793..31e300ccb79 100644
--- a/lldb/include/lldb/Target/LanguageRuntime.h
+++ b/lldb/include/lldb/Target/LanguageRuntime.h
@@ -54,7 +54,8 @@ public:
                               lldb::DynamicValueType use_dynamic, 
                               TypeAndOrName &class_type_or_name, 
                               Address &address,
-                              Value::ValueType &value_type) = 0;
+                              Value::ValueType &value_type,
+                              Error &error) = 0;
     
     // This call should return a CompilerType given a generic type name
     // and an ExecutionContextScope in which one can actually fetch
diff --git a/lldb/source/Core/ValueObjectDynamicValue.cpp b/lldb/source/Core/ValueObjectDynamicValue.cpp
index 0ac86a68f19..3a34fdf3a86 100644
--- a/lldb/source/Core/ValueObjectDynamicValue.cpp
+++ b/lldb/source/Core/ValueObjectDynamicValue.cpp
@@ -187,23 +187,41 @@ ValueObjectDynamicValue::UpdateValue ()
     LanguageRuntime *runtime = nullptr;
 
     lldb::LanguageType known_type = m_parent->GetObjectRuntimeLanguage();
+    
+    Error dynamic_type_discovery_error;
+    
     if (known_type != lldb::eLanguageTypeUnknown && known_type != lldb::eLanguageTypeC)
     {
         runtime = process->GetLanguageRuntime (known_type);
         if (runtime)
-            found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address, value_type);
+            found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent,
+                                                                    m_use_dynamic,
+                                                                    class_type_or_name,
+                                                                    dynamic_address,
+                                                                    value_type,
+                                                                    dynamic_type_discovery_error);
     }
     else
     {
         runtime = process->GetLanguageRuntime (lldb::eLanguageTypeC_plus_plus);
         if (runtime)
-            found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address, value_type);
+            found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent,
+                                                                    m_use_dynamic,
+                                                                    class_type_or_name,
+                                                                    dynamic_address,
+                                                                    value_type,
+                                                                    dynamic_type_discovery_error);
 
         if (!found_dynamic_type)
         {
             runtime = process->GetLanguageRuntime (lldb::eLanguageTypeObjC);
             if (runtime)
-                found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address, value_type);
+                found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent,
+                                                                        m_use_dynamic,
+                                                                        class_type_or_name,
+                                                                        dynamic_address,
+                                                                        value_type,
+                                                                        dynamic_type_discovery_error);
         }
     }
 
@@ -229,16 +247,24 @@ ValueObjectDynamicValue::UpdateValue ()
         m_type_impl.Clear();
     }
 
-    // If we don't have a dynamic type, then make ourselves just a echo of our parent.
-    // Or we could return false, and make ourselves an echo of our parent?
+    // If we don't have a dynamic type...
     if (!found_dynamic_type)
     {
-        if (m_dynamic_type_info)
-            SetValueDidChange(true);
-        ClearDynamicTypeInformation();
-        m_dynamic_type_info.Clear();
-        m_value = m_parent->GetValue();
-        m_error = m_value.GetValueAsData (&exe_ctx, m_data, 0, GetModule().get());
+        // ...and it's not because of an error, let's make ourselves an echo of our parent
+        if (dynamic_type_discovery_error.Success())
+        {
+            if (m_dynamic_type_info)
+                SetValueDidChange(true);
+            ClearDynamicTypeInformation();
+            m_dynamic_type_info.Clear();
+            m_value = m_parent->GetValue();
+            m_error = m_value.GetValueAsData (&exe_ctx, m_data, 0, GetModule().get());
+        }
+        else
+        {
+            // ...but if it is because of an error, let's report that to the user
+            m_error = dynamic_type_discovery_error;
+        }
         return m_error.Success();
     }
 
diff --git a/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
index ab5cbac2dde..84cbc11a5f0 100644
--- a/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
@@ -53,7 +53,8 @@ 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,
+                                                     Error &error)
 {
     // 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
@@ -63,6 +64,7 @@ ItaniumABILanguageRuntime::GetDynamicTypeAndAddress (ValueObject &in_value,
     // start of the value object which holds the dynamic type.
     //
     
+    error.Clear();
     class_type_or_name.Clear();
     value_type = Value::ValueType::eValueTypeScalar;
     
diff --git a/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h b/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h
index c06b9863a9b..d12752748b9 100644
--- a/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h
+++ b/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h
@@ -53,7 +53,8 @@ namespace lldb_private {
                                  lldb::DynamicValueType use_dynamic,
                                  TypeAndOrName &class_type_or_name,
                                  Address &address,
-                                 Value::ValueType &value_type) override;
+                                 Value::ValueType &value_type,
+                                 Error &error) override;
         
         TypeAndOrName
         FixUpDynamicType(const TypeAndOrName& type_and_or_name,
diff --git a/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.cpp
index c752971e7a0..594b5cdeea7 100644
--- a/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.cpp
@@ -140,11 +140,15 @@ GoLanguageRuntime::CouldHaveDynamicValue (ValueObject &in_value)
 }
 
 bool
-GoLanguageRuntime::GetDynamicTypeAndAddress(ValueObject &in_value, lldb::DynamicValueType use_dynamic,
-                                            TypeAndOrName &class_type_or_name, Address &dynamic_address,
-                                            Value::ValueType &value_type)
+GoLanguageRuntime::GetDynamicTypeAndAddress(ValueObject &in_value,
+                                            lldb::DynamicValueType use_dynamic,
+                                            TypeAndOrName &class_type_or_name,
+                                            Address &dynamic_address,
+                                            Value::ValueType &value_type,
+                                            Error &error)
 {
     value_type = Value::eValueTypeScalar;
+    error.Clear();
     class_type_or_name.Clear();
     if (CouldHaveDynamicValue (in_value))
     {
diff --git a/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.h b/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.h
index 596d2888dc8..6981d4a8c59 100644
--- a/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.h
+++ b/lldb/source/Plugins/LanguageRuntime/Go/GoLanguageRuntime.h
@@ -61,9 +61,12 @@ namespace lldb_private {
             return false;
         }
 
-        bool GetDynamicTypeAndAddress(ValueObject &in_value, lldb::DynamicValueType use_dynamic,
-                                      TypeAndOrName &class_type_or_name, Address &address,
-                                      Value::ValueType &value_type) override;
+        bool GetDynamicTypeAndAddress(ValueObject &in_value,
+                                      lldb::DynamicValueType use_dynamic,
+                                      TypeAndOrName &class_type_or_name,
+                                      Address &address,
+                                      Value::ValueType &value_type,
+                                      Error &error) override;
 
         bool CouldHaveDynamicValue(ValueObject &in_value) override;
 
diff --git a/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.cpp
index 07312a8af0d..1ff5a4dbbe5 100644
--- a/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.cpp
@@ -105,10 +105,14 @@ GetDynamicTypeId(ExecutionContext *exe_ctx, Target *target, ValueObject &in_valu
 }
 
 bool
-JavaLanguageRuntime::GetDynamicTypeAndAddress(ValueObject &in_value, lldb::DynamicValueType use_dynamic,
-                                              TypeAndOrName &class_type_or_name, Address &dynamic_address,
-                                              Value::ValueType &value_type)
+JavaLanguageRuntime::GetDynamicTypeAndAddress(ValueObject &in_value,
+                                              lldb::DynamicValueType use_dynamic,
+                                              TypeAndOrName &class_type_or_name,
+                                              Address &dynamic_address,
+                                              Value::ValueType &value_type,
+                                              Error &error)
 {
+    error.Clear();
     class_type_or_name.Clear();
 
     // null references don't have a dynamic type
diff --git a/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.h b/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.h
index 83ed35dbb59..e90ba37d2bb 100644
--- a/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.h
+++ b/lldb/source/Plugins/LanguageRuntime/Java/JavaLanguageRuntime.h
@@ -74,9 +74,12 @@ public:
     CouldHaveDynamicValue(ValueObject &in_value) override;
 
     bool
-    GetDynamicTypeAndAddress(ValueObject &in_value, lldb::DynamicValueType use_dynamic,
-                             TypeAndOrName &class_type_or_name, Address &address,
-                             Value::ValueType &value_type) override;
+    GetDynamicTypeAndAddress(ValueObject &in_value,
+                             lldb::DynamicValueType use_dynamic,
+                             TypeAndOrName &class_type_or_name,
+                             Address &address,
+                             Value::ValueType &value_type,
+                             Error &error) override;
 
 protected:
     JavaLanguageRuntime(Process *process);
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
index 9430e38f694..de2345e8a43 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
@@ -270,8 +270,10 @@ AppleObjCRuntime::GetDynamicTypeAndAddress (ValueObject &in_value,
                                             lldb::DynamicValueType use_dynamic, 
                                             TypeAndOrName &class_type_or_name, 
                                             Address &address,
-                                            Value::ValueType &value_type)
+                                            Value::ValueType &value_type,
+                                            Error &error)
 {
+    error.Clear();
     return false;
 }
 
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
index 342824e79b1..46001552c8a 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
@@ -63,7 +63,8 @@ public:
                               lldb::DynamicValueType use_dynamic, 
                               TypeAndOrName &class_type_or_name, 
                               Address &address,
-                              Value::ValueType &value_type) override;
+                              Value::ValueType &value_type,
+                              Error &error) override;
 
     TypeAndOrName
     FixUpDynamicType (const TypeAndOrName& type_and_or_name,
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
index 805fca7a31b..ef8679eae3c 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
@@ -50,8 +50,10 @@ AppleObjCRuntimeV1::GetDynamicTypeAndAddress (ValueObject &in_value,
                                               lldb::DynamicValueType use_dynamic,
                                               TypeAndOrName &class_type_or_name,
                                               Address &address,
-                                              Value::ValueType &value_type)
+                                              Value::ValueType &value_type,
+                                              Error &error)
 {
+    error.Clear();
     class_type_or_name.Clear();
     value_type = Value::ValueType::eValueTypeScalar;
     if (CouldHaveDynamicValue(in_value))
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h
index 9f9fcc69b68..18b9f6ae875 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h
@@ -125,7 +125,8 @@ public:
                              lldb::DynamicValueType use_dynamic, 
                              TypeAndOrName &class_type_or_name, 
                              Address &address,
-                             Value::ValueType &value_type) override;
+                             Value::ValueType &value_type,
+                             Error &error) override;
 
     UtilityFunction *
     CreateObjectChecker(const char *) override;
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
index 091c157142c..96924828257 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
@@ -407,7 +407,8 @@ AppleObjCRuntimeV2::GetDynamicTypeAndAddress (ValueObject &in_value,
                                               DynamicValueType use_dynamic, 
                                               TypeAndOrName &class_type_or_name, 
                                               Address &address,
-                                              Value::ValueType &value_type)
+                                              Value::ValueType &value_type,
+                                              Error &error)
 {
     // We should never get here with a null process...
     assert (m_process != NULL);
@@ -422,6 +423,7 @@ AppleObjCRuntimeV2::GetDynamicTypeAndAddress (ValueObject &in_value,
     else
         assert (in_value.GetTargetSP().get() == m_process->CalculateTarget().get());
     
+    error.Clear();
     class_type_or_name.Clear();
     value_type = Value::ValueType::eValueTypeScalar;
 
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
index 8b4ca8f4e9b..181cf4ea040 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
@@ -63,7 +63,8 @@ public:
                              lldb::DynamicValueType use_dynamic,
                              TypeAndOrName &class_type_or_name,
                              Address &address,
-                             Value::ValueType &value_type) override;
+                             Value::ValueType &value_type,
+                             Error &error) override;
     
     UtilityFunction *
     CreateObjectChecker(const char *) override;
diff --git a/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.cpp
index 8d1dfdcf4f7..448655f258a 100644
--- a/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.cpp
@@ -906,10 +906,14 @@ RenderScriptRuntime::IsVTableName(const char *name)
 }
 
 bool
-RenderScriptRuntime::GetDynamicTypeAndAddress(ValueObject &in_value, lldb::DynamicValueType use_dynamic,
-                                              TypeAndOrName &class_type_or_name, Address &address,
-                                              Value::ValueType &value_type)
+RenderScriptRuntime::GetDynamicTypeAndAddress(ValueObject &in_value,
+                                              lldb::DynamicValueType use_dynamic,
+                                              TypeAndOrName &class_type_or_name,
+                                              Address &address,
+                                              Value::ValueType &value_type,
+                                              Error &error)
 {
+    error.Clear();
     return false;
 }
 
diff --git a/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.h b/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.h
index 2a0839a1a78..7747a3770ce 100644
--- a/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.h
+++ b/lldb/source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.h
@@ -178,9 +178,12 @@ public:
     IsVTableName(const char *name) override;
 
     bool
-    GetDynamicTypeAndAddress(ValueObject &in_value, lldb::DynamicValueType use_dynamic,
-                             TypeAndOrName &class_type_or_name, Address &address,
-                             Value::ValueType &value_type) override;
+    GetDynamicTypeAndAddress(ValueObject &in_value,
+                             lldb::DynamicValueType use_dynamic,
+                             TypeAndOrName &class_type_or_name,
+                             Address &address,
+                             Value::ValueType &value_type,
+                             Error &error) override;
 
     TypeAndOrName
     FixUpDynamicType(const TypeAndOrName &type_and_or_name, ValueObject &static_value) override;