Preparatory infrastructural work to support dynamically determining sizes of ObjC types via the runtime

This is necessary because the byte size of an ObjC class type is not reliably statically knowable (e.g. because superclasses sit deep in frameworks that we have no debug info for)
The lack of reliable size info is a problem when trying to freeze-dry an ObjC instance (not the pointer, the pointee)

This commit lays the foundation for having language runtimes help in figuring out byte sizes, and having ClangASTType ask for runtime help
No feature change as no runtime actually implements the logic, and nowhere is an ExecutionContext passed in yet

llvm-svn: 227274

26 files changed, 110 insertions, 86 deletions

diff --git a/lldb/include/lldb/Symbol/ClangASTType.h b/lldb/include/lldb/Symbol/ClangASTType.h
index ef23a8be645..4011ff923a9 100644
--- a/lldb/include/lldb/Symbol/ClangASTType.h
+++ b/lldb/include/lldb/Symbol/ClangASTType.h
@@ -347,10 +347,10 @@ public:
     //----------------------------------------------------------------------
 
     uint64_t
-    GetByteSize () const;
+    GetByteSize (ExecutionContext *exe_ctx) const;
 
     uint64_t
-    GetBitSize () const;
+    GetBitSize (ExecutionContext *exe_ctx) const;
 
     lldb::Encoding
     GetEncoding (uint64_t &count) const;
diff --git a/lldb/include/lldb/Target/LanguageRuntime.h b/lldb/include/lldb/Target/LanguageRuntime.h
index 0aaa67c2382..d5ed8195647 100644
--- a/lldb/include/lldb/Target/LanguageRuntime.h
+++ b/lldb/include/lldb/Target/LanguageRuntime.h
@@ -102,6 +102,13 @@ public:
     
     virtual lldb::SearchFilterSP
     CreateExceptionSearchFilter ();
+    
+    virtual bool
+    GetTypeBitSize (const ClangASTType& clang_type,
+                    uint64_t &size)
+    {
+        return false;
+    }
 
 protected:
     //------------------------------------------------------------------
diff --git a/lldb/include/lldb/Utility/ProcessStructReader.h b/lldb/include/lldb/Utility/ProcessStructReader.h
index 7b05d93151a..d053b702462 100644
--- a/lldb/include/lldb/Utility/ProcessStructReader.h
+++ b/lldb/include/lldb/Utility/ProcessStructReader.h
@@ -59,7 +59,7 @@ namespace lldb_private {
                 // no support for bitfields in here (yet)
                 if (is_bitfield)
                     return;
-                auto size = field_type.GetByteSize();
+                auto size = field_type.GetByteSize(nullptr);
                 // no support for things larger than a uint64_t (yet)
                 if (size > 8)
                     return;
@@ -67,7 +67,7 @@ namespace lldb_private {
                 size_t byte_index = static_cast<size_t>(bit_offset / 8);
                 m_fields[const_name] = FieldImpl{field_type, byte_index, static_cast<size_t>(size)};
             }
-            size_t total_size = struct_type.GetByteSize();
+            size_t total_size = struct_type.GetByteSize(nullptr);
             lldb::DataBufferSP buffer_sp(new DataBufferHeap(total_size,0));
             Error error;
             process->ReadMemoryFromInferior(base_addr,
diff --git a/lldb/source/API/SBType.cpp b/lldb/source/API/SBType.cpp
index 8a0f5d848a3..1f253804d4f 100644
--- a/lldb/source/API/SBType.cpp
+++ b/lldb/source/API/SBType.cpp
@@ -143,7 +143,7 @@ SBType::GetByteSize()
     if (!IsValid())
         return 0;
     
-    return m_opaque_sp->GetClangASTType(false).GetByteSize();
+    return m_opaque_sp->GetClangASTType(false).GetByteSize(nullptr);
     
 }
 
diff --git a/lldb/source/Commands/CommandObjectMemory.cpp b/lldb/source/Commands/CommandObjectMemory.cpp
index 569d13a3084..ed650a18602 100644
--- a/lldb/source/Commands/CommandObjectMemory.cpp
+++ b/lldb/source/Commands/CommandObjectMemory.cpp
@@ -567,7 +567,7 @@ protected:
                 --pointer_count;
             }
 
-            m_format_options.GetByteSizeValue() = clang_ast_type.GetByteSize();
+            m_format_options.GetByteSizeValue() = clang_ast_type.GetByteSize(nullptr);
             
             if (m_format_options.GetByteSizeValue() == 0)
             {
@@ -690,7 +690,7 @@ protected:
             if (m_format_options.GetFormatValue().OptionWasSet() == false)
                 m_format_options.GetFormatValue().SetCurrentValue(eFormatDefault);
 
-            bytes_read = clang_ast_type.GetByteSize() * m_format_options.GetCountValue().GetCurrentValue();
+            bytes_read = clang_ast_type.GetByteSize(nullptr) * m_format_options.GetCountValue().GetCurrentValue();
         }
         else if (m_format_options.GetFormatValue().GetCurrentValue() != eFormatCString)
         {
@@ -1114,7 +1114,7 @@ protected:
           if (process->GetTarget().EvaluateExpression(m_memory_options.m_expr.GetStringValue(), frame, result_sp) && result_sp.get())
           {
               uint64_t value = result_sp->GetValueAsUnsigned(0);
-              switch (result_sp->GetClangType().GetByteSize())
+              switch (result_sp->GetClangType().GetByteSize(nullptr))
               {
                   case 1: {
                       uint8_t byte = (uint8_t)value;
diff --git a/lldb/source/Core/Value.cpp b/lldb/source/Core/Value.cpp
index db33fce4a03..a416d0745a6 100644
--- a/lldb/source/Core/Value.cpp
+++ b/lldb/source/Core/Value.cpp
@@ -277,7 +277,7 @@ Value::GetValueByteSize (Error *error_ptr)
         {
             const ClangASTType &ast_type = GetClangType();
             if (ast_type.IsValid())
-                byte_size = ast_type.GetByteSize();
+                byte_size = ast_type.GetByteSize(nullptr);
         }
         break;
     }
@@ -434,7 +434,7 @@ Value::GetValueAsData (ExecutionContext *exe_ctx,
                 lldb::Encoding type_encoding = ast_type.GetEncoding(type_encoding_count);
                 
                 if (type_encoding == eEncodingUint || type_encoding == eEncodingSint)
-                    limit_byte_size = ast_type.GetByteSize();
+                    limit_byte_size = ast_type.GetByteSize(nullptr);
             }
             
             if (m_value.GetData (data, limit_byte_size))
diff --git a/lldb/source/Core/ValueObject.cpp b/lldb/source/Core/ValueObject.cpp
index 3937424ed7e..99b38dd6264 100644
--- a/lldb/source/Core/ValueObject.cpp
+++ b/lldb/source/Core/ValueObject.cpp
@@ -971,7 +971,7 @@ ValueObject::GetPointeeData (DataExtractor& data,
     if (item_count == 0)
         return 0;
     
-    const uint64_t item_type_size = pointee_or_element_clang_type.GetByteSize();
+    const uint64_t item_type_size = pointee_or_element_clang_type.GetByteSize(nullptr);
     const uint64_t bytes = item_count * item_type_size;
     const uint64_t offset = item_idx * item_type_size;
     
@@ -1047,7 +1047,7 @@ ValueObject::GetPointeeData (DataExtractor& data,
                 break;
             case eAddressTypeHost:
                 {
-                    const uint64_t max_bytes = GetClangType().GetByteSize();
+                    const uint64_t max_bytes = GetClangType().GetByteSize(nullptr);
                     if (max_bytes > offset)
                     {
                         size_t bytes_read = std::min<uint64_t>(max_bytes - offset, bytes);
@@ -2225,7 +2225,7 @@ ValueObject::GetSyntheticChildAtOffset(uint32_t offset, const ClangASTType& type
     ValueObjectChild *synthetic_child = new ValueObjectChild(*this,
                                                              type,
                                                              name_const_str,
-                                                             type.GetByteSize(),
+                                                             type.GetByteSize(nullptr),
                                                              offset,
                                                              0,
                                                              0,
@@ -2266,7 +2266,7 @@ ValueObject::GetSyntheticBase (uint32_t offset, const ClangASTType& type, bool c
     ValueObjectChild *synthetic_child = new ValueObjectChild(*this,
                                                              type,
                                                              name_const_str,
-                                                             type.GetByteSize(),
+                                                             type.GetByteSize(nullptr),
                                                              offset,
                                                              0,
                                                              0,
diff --git a/lldb/source/Core/ValueObjectConstResult.cpp b/lldb/source/Core/ValueObjectConstResult.cpp
index fc870d72622..cbeb2ab47b2 100644
--- a/lldb/source/Core/ValueObjectConstResult.cpp
+++ b/lldb/source/Core/ValueObjectConstResult.cpp
@@ -257,7 +257,7 @@ uint64_t
 ValueObjectConstResult::GetByteSize()
 {
     if (m_byte_size == 0)
-        m_byte_size = GetClangType().GetByteSize();
+        m_byte_size = GetClangType().GetByteSize(nullptr);
     return m_byte_size;
 }
 
diff --git a/lldb/source/Core/ValueObjectMemory.cpp b/lldb/source/Core/ValueObjectMemory.cpp
index 5fbe87b6652..9f1953138f6 100644
--- a/lldb/source/Core/ValueObjectMemory.cpp
+++ b/lldb/source/Core/ValueObjectMemory.cpp
@@ -169,7 +169,7 @@ ValueObjectMemory::GetByteSize()
 {
     if (m_type_sp)
         return m_type_sp->GetByteSize();
-    return m_clang_type.GetByteSize ();
+    return m_clang_type.GetByteSize (nullptr);
 }
 
 lldb::ValueType
diff --git a/lldb/source/Core/ValueObjectVariable.cpp b/lldb/source/Core/ValueObjectVariable.cpp
index ab74a50e7cd..e4fd212cbfa 100644
--- a/lldb/source/Core/ValueObjectVariable.cpp
+++ b/lldb/source/Core/ValueObjectVariable.cpp
@@ -110,7 +110,7 @@ ValueObjectVariable::GetByteSize()
     if (!type.IsValid())
         return 0;
     
-    return type.GetByteSize();
+    return type.GetByteSize(nullptr);
 }
 
 lldb::ValueType
diff --git a/lldb/source/DataFormatters/CXXFormatterFunctions.cpp b/lldb/source/DataFormatters/CXXFormatterFunctions.cpp
index 04cdadf5a98..5aa8289794c 100644
--- a/lldb/source/DataFormatters/CXXFormatterFunctions.cpp
+++ b/lldb/source/DataFormatters/CXXFormatterFunctions.cpp
@@ -317,7 +317,7 @@ lldb_private::formatters::WCharStringSummaryProvider (ValueObject& valobj, Strea
         return false;
 
     ClangASTType wchar_clang_type = ClangASTContext::GetBasicType(ast, lldb::eBasicTypeWChar);
-    const uint32_t wchar_size = wchar_clang_type.GetBitSize();
+    const uint32_t wchar_size = wchar_clang_type.GetBitSize(nullptr);
 
     ReadStringAndDumpToStreamOptions options(valobj);
     options.SetLocation(data_addr);
diff --git a/lldb/source/DataFormatters/LibCxx.cpp b/lldb/source/DataFormatters/LibCxx.cpp
index 26bbcf91242..33b85322330 100644
--- a/lldb/source/DataFormatters/LibCxx.cpp
+++ b/lldb/source/DataFormatters/LibCxx.cpp
@@ -139,7 +139,7 @@ lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::GetChildAtIndex (si
             return ValueObjectSP();
     }
     bool bit_set = ((byte & mask) != 0);
-    DataBufferSP buffer_sp(new DataBufferHeap(m_bool_type.GetByteSize(),0));
+    DataBufferSP buffer_sp(new DataBufferHeap(m_bool_type.GetByteSize(nullptr),0));
     if (bit_set && buffer_sp && buffer_sp->GetBytes())
         *(buffer_sp->GetBytes()) = 1; // regardless of endianness, anything non-zero is true
     StreamString name; name.Printf("[%" PRIu64 "]", (uint64_t)idx);
diff --git a/lldb/source/DataFormatters/LibCxxInitializerList.cpp b/lldb/source/DataFormatters/LibCxxInitializerList.cpp
index e76b0bec95c..91f1f90507a 100644
--- a/lldb/source/DataFormatters/LibCxxInitializerList.cpp
+++ b/lldb/source/DataFormatters/LibCxxInitializerList.cpp
@@ -107,7 +107,7 @@ lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::Update()
     if (kind != lldb::eTemplateArgumentKindType || false == m_element_type.IsValid())
         return false;
     
-    m_element_size = m_element_type.GetByteSize();
+    m_element_size = m_element_type.GetByteSize(nullptr);
     
     if (m_element_size > 0)
         m_start = m_backend.GetChildMemberWithName(g___begin_,true).get(); // store raw pointers or end up with a circular dependency
diff --git a/lldb/source/DataFormatters/LibCxxVector.cpp b/lldb/source/DataFormatters/LibCxxVector.cpp
index 26c62afbed2..d0e6be486d6 100644
--- a/lldb/source/DataFormatters/LibCxxVector.cpp
+++ b/lldb/source/DataFormatters/LibCxxVector.cpp
@@ -115,7 +115,7 @@ lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update()
     if (!data_type_finder_sp)
         return false;
     m_element_type = data_type_finder_sp->GetClangType().GetPointeeType();
-    m_element_size = m_element_type.GetByteSize();
+    m_element_size = m_element_type.GetByteSize(nullptr);
     
     if (m_element_size > 0)
     {
diff --git a/lldb/source/Expression/IRForTarget.cpp b/lldb/source/Expression/IRForTarget.cpp
index 8e75c32183e..42390b35fdd 100644
--- a/lldb/source/Expression/IRForTarget.cpp
+++ b/lldb/source/Expression/IRForTarget.cpp
@@ -590,7 +590,7 @@ IRForTarget::CreateResultVariable (llvm::Function &llvm_function)
                                                      &result_decl->getASTContext());
     }
 
-    if (m_result_type.GetBitSize() == 0)
+    if (m_result_type.GetBitSize(nullptr) == 0)
     {
         lldb_private::StreamString type_desc_stream;
         m_result_type.DumpTypeDescription(&type_desc_stream);
@@ -617,7 +617,7 @@ IRForTarget::CreateResultVariable (llvm::Function &llvm_function)
     if (log)
         log->Printf("Creating a new result global: \"%s\" with size 0x%" PRIx64,
                     m_result_name.GetCString(),
-                    m_result_type.GetByteSize());
+                    m_result_type.GetByteSize(nullptr));
 
     // Construct a new result global and set up its metadata
 
@@ -1518,7 +1518,7 @@ IRForTarget::MaybeHandleVariable (Value *llvm_value_ptr)
             value_type = global_variable->getType();
         }
 
-        const uint64_t value_size = clang_type.GetByteSize();
+        const uint64_t value_size = clang_type.GetByteSize(nullptr);
         lldb::offset_t value_alignment = (clang_type.GetTypeBitAlign() + 7ull) / 8ull;
 
         if (log)
diff --git a/lldb/source/Expression/Materializer.cpp b/lldb/source/Expression/Materializer.cpp
index b11921635e5..f1f2f99eed5 100644
--- a/lldb/source/Expression/Materializer.cpp
+++ b/lldb/source/Expression/Materializer.cpp
@@ -49,7 +49,7 @@ Materializer::AddStructMember (Entity &entity)
 void
 Materializer::Entity::SetSizeAndAlignmentFromType (ClangASTType &type)
 {
-    m_size = type.GetByteSize();
+    m_size = type.GetByteSize(nullptr);
     
     uint32_t bit_alignment = type.GetTypeBitAlign();
     
@@ -780,7 +780,7 @@ public:
             
             const lldb::addr_t load_addr = process_address + m_offset;
 
-            size_t byte_size = m_type.GetByteSize();
+            size_t byte_size = m_type.GetByteSize(nullptr);
             size_t bit_align = m_type.GetTypeBitAlign();
             size_t byte_align = (bit_align + 7) / 8;
             
diff --git a/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp b/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp
index 5073b13f09a..42acba232de 100644
--- a/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp
+++ b/lldb/source/Plugins/ABI/MacOSX-arm/ABIMacOSX_arm.cpp
@@ -334,11 +334,11 @@ ABIMacOSX_arm::GetArgumentValues (Thread &thread,
             size_t bit_width = 0;
             if (clang_type.IsIntegerType (is_signed))
             {
-                bit_width = clang_type.GetBitSize();
+                bit_width = clang_type.GetBitSize(nullptr);
             }
             else if (clang_type.IsPointerOrReferenceType ())
             {
-                bit_width = clang_type.GetBitSize();
+                bit_width = clang_type.GetBitSize(nullptr);
             }
             else
             {
@@ -437,7 +437,7 @@ ABIMacOSX_arm::GetReturnValueObjectImpl (Thread &thread,
     const RegisterInfo *r0_reg_info = reg_ctx->GetRegisterInfoByName("r0", 0);
     if (clang_type.IsIntegerType (is_signed))
     {
-        size_t bit_width = clang_type.GetBitSize();
+        size_t bit_width = clang_type.GetBitSize(nullptr);
         
         switch (bit_width)
         {
diff --git a/lldb/source/Plugins/ABI/MacOSX-arm64/ABIMacOSX_arm64.cpp b/lldb/source/Plugins/ABI/MacOSX-arm64/ABIMacOSX_arm64.cpp
index 465257db31d..c2ba165afb4 100644
--- a/lldb/source/Plugins/ABI/MacOSX-arm64/ABIMacOSX_arm64.cpp
+++ b/lldb/source/Plugins/ABI/MacOSX-arm64/ABIMacOSX_arm64.cpp
@@ -322,11 +322,11 @@ ABIMacOSX_arm64::GetArgumentValues (Thread &thread, ValueList &values) const
             size_t bit_width = 0;
             if (value_type.IsIntegerType (is_signed))
             {
-                bit_width = value_type.GetBitSize();
+                bit_width = value_type.GetBitSize(nullptr);
             }
             else if (value_type.IsPointerOrReferenceType ())
             {
-                bit_width = value_type.GetBitSize();
+                bit_width = value_type.GetBitSize(nullptr);
             }
             else
             {
@@ -709,7 +709,7 @@ LoadValueFromConsecutiveGPRRegisters (ExecutionContext &exe_ctx,
                                       uint32_t &NSRN,       // NSRN (see ABI documentation)
                                       DataExtractor &data)
 {
-    const size_t byte_size = value_type.GetByteSize();
+    const size_t byte_size = value_type.GetByteSize(nullptr);
     
     if (byte_size == 0)
         return false;
@@ -728,7 +728,7 @@ LoadValueFromConsecutiveGPRRegisters (ExecutionContext &exe_ctx,
         {
             if (!base_type)
                 return false;
-            const size_t base_byte_size = base_type.GetByteSize();
+            const size_t base_byte_size = base_type.GetByteSize(nullptr);
             printf ("ClangASTContext::IsHomogeneousAggregate() => base_byte_size = %" PRIu64 "\n", (uint64_t) base_byte_size);
             uint32_t data_offset = 0;
 
@@ -871,7 +871,7 @@ ABIMacOSX_arm64::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_
     if (!reg_ctx)
         return return_valobj_sp;
     
-    const size_t byte_size = return_clang_type.GetByteSize();
+    const size_t byte_size = return_clang_type.GetByteSize(nullptr);
 
     const uint32_t type_flags = return_clang_type.GetTypeInfo (NULL);
     if (type_flags & eTypeIsScalar ||
diff --git a/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp b/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
index ba7f5b3fe59..ee5b9298721 100644
--- a/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
+++ b/lldb/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
@@ -552,7 +552,7 @@ ABIMacOSX_i386::GetArgumentValues (Thread &thread,
             if (clang_type.IsIntegerType (is_signed))
             {
                 ReadIntegerArgument(value->GetScalar(),
-                                    clang_type.GetBitSize(),
+                                    clang_type.GetBitSize(nullptr),
                                     is_signed,
                                     thread.GetProcess().get(), 
                                     current_stack_argument);
@@ -560,7 +560,7 @@ ABIMacOSX_i386::GetArgumentValues (Thread &thread,
             else if (clang_type.IsPointerType())
             {
                 ReadIntegerArgument(value->GetScalar(),
-                                    clang_type.GetBitSize(),
+                                    clang_type.GetBitSize(nullptr),
                                     false,
                                     thread.GetProcess().get(),
                                     current_stack_argument);
@@ -672,7 +672,7 @@ ABIMacOSX_i386::GetReturnValueObjectImpl (Thread &thread,
             
     if (clang_type.IsIntegerType (is_signed))
     {
-        size_t bit_width = clang_type.GetBitSize();
+        size_t bit_width = clang_type.GetBitSize(nullptr);
         
         unsigned eax_id = reg_ctx->GetRegisterInfoByName("eax", 0)->kinds[eRegisterKindLLDB];
         unsigned edx_id = reg_ctx->GetRegisterInfoByName("edx", 0)->kinds[eRegisterKindLLDB];
diff --git a/lldb/source/Plugins/ABI/SysV-ppc/ABISysV_ppc.cpp b/lldb/source/Plugins/ABI/SysV-ppc/ABISysV_ppc.cpp
index adb3313d1a3..f53ed92a880 100644
--- a/lldb/source/Plugins/ABI/SysV-ppc/ABISysV_ppc.cpp
+++ b/lldb/source/Plugins/ABI/SysV-ppc/ABISysV_ppc.cpp
@@ -444,7 +444,7 @@ ABISysV_ppc::GetArgumentValues (Thread &thread,
         if (clang_type.IsIntegerType (is_signed))
         {
             ReadIntegerArgument(value->GetScalar(),
-                                clang_type.GetBitSize(),
+                                clang_type.GetBitSize(nullptr),
                                 is_signed,
                                 thread,
                                 argument_register_ids,
@@ -454,7 +454,7 @@ ABISysV_ppc::GetArgumentValues (Thread &thread,
         else if (clang_type.IsPointerType ())
         {
             ReadIntegerArgument(value->GetScalar(),
-                                clang_type.GetBitSize(),
+                                clang_type.GetBitSize(nullptr),
                                 false,
                                 thread,
                                 argument_register_ids,
@@ -524,7 +524,7 @@ ABISysV_ppc::SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjec
             error.SetErrorString ("We don't support returning complex values at present");
         else
         {
-            size_t bit_width = clang_type.GetBitSize();
+            size_t bit_width = clang_type.GetBitSize(nullptr);
             if (bit_width <= 64)
             {
                 DataExtractor data;
@@ -588,7 +588,7 @@ ABISysV_ppc::GetReturnValueObjectSimple (Thread &thread,
         {
             // Extract the register context so we can read arguments from registers
 
-            const size_t byte_size = return_clang_type.GetByteSize();
+            const size_t byte_size = return_clang_type.GetByteSize(nullptr);
             uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned(reg_ctx->GetRegisterInfoByName("r3", 0), 0);
             const bool is_signed = (type_flags & eTypeIsSigned) != 0;
             switch (byte_size)
@@ -637,7 +637,7 @@ ABISysV_ppc::GetReturnValueObjectSimple (Thread &thread,
             }
             else
             {
-                const size_t byte_size = return_clang_type.GetByteSize();
+                const size_t byte_size = return_clang_type.GetByteSize(nullptr);
                 if (byte_size <= sizeof(long double))
                 {
                     const RegisterInfo *f1_info = reg_ctx->GetRegisterInfoByName("f1", 0);
@@ -681,7 +681,7 @@ ABISysV_ppc::GetReturnValueObjectSimple (Thread &thread,
     }
     else if (type_flags & eTypeIsVector)
     {
-        const size_t byte_size = return_clang_type.GetByteSize();
+        const size_t byte_size = return_clang_type.GetByteSize(nullptr);
         if (byte_size > 0)
         {
 
@@ -742,7 +742,7 @@ ABISysV_ppc::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_clan
     if (!reg_ctx_sp)
         return return_valobj_sp;
 
-    const size_t bit_width = return_clang_type.GetBitSize();
+    const size_t bit_width = return_clang_type.GetBitSize(nullptr);
     if (return_clang_type.IsAggregateType())
     {
         Target *target = exe_ctx.GetTargetPtr();
@@ -784,7 +784,7 @@ ABISysV_ppc::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_clan
                 uint32_t count;
 
                 ClangASTType field_clang_type = return_clang_type.GetFieldAtIndex (idx, name, &field_bit_offset, NULL, NULL);
-                const size_t field_bit_width = field_clang_type.GetBitSize();
+                const size_t field_bit_width = field_clang_type.GetBitSize(nullptr);
 
                 // If there are any unaligned fields, this is stored in memory.
                 if (field_bit_offset % field_bit_width != 0)
diff --git a/lldb/source/Plugins/ABI/SysV-ppc64/ABISysV_ppc64.cpp b/lldb/source/Plugins/ABI/SysV-ppc64/ABISysV_ppc64.cpp
index 46f1e1023f0..8a942b5dae8 100644
--- a/lldb/source/Plugins/ABI/SysV-ppc64/ABISysV_ppc64.cpp
+++ b/lldb/source/Plugins/ABI/SysV-ppc64/ABISysV_ppc64.cpp
@@ -444,7 +444,7 @@ ABISysV_ppc64::GetArgumentValues (Thread &thread,
         if (clang_type.IsIntegerType (is_signed))
         {
             ReadIntegerArgument(value->GetScalar(),
-                                clang_type.GetBitSize(),
+                                clang_type.GetBitSize(nullptr),
                                 is_signed,
                                 thread,
                                 argument_register_ids,
@@ -454,7 +454,7 @@ ABISysV_ppc64::GetArgumentValues (Thread &thread,
         else if (clang_type.IsPointerType ())
         {
             ReadIntegerArgument(value->GetScalar(),
-                                clang_type.GetBitSize(),
+                                clang_type.GetBitSize(nullptr),
                                 false,
                                 thread,
                                 argument_register_ids,
@@ -524,7 +524,7 @@ ABISysV_ppc64::SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObj
             error.SetErrorString ("We don't support returning complex values at present");
         else
         {
-            size_t bit_width = clang_type.GetBitSize();
+            size_t bit_width = clang_type.GetBitSize(nullptr);
             if (bit_width <= 64)
             {
                 DataExtractor data;
@@ -588,7 +588,7 @@ ABISysV_ppc64::GetReturnValueObjectSimple (Thread &thread,
         {
             // Extract the register context so we can read arguments from registers
 
-            const size_t byte_size = return_clang_type.GetByteSize();
+            const size_t byte_size = return_clang_type.GetByteSize(nullptr);
             uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned(reg_ctx->GetRegisterInfoByName("r3", 0), 0);
             const bool is_signed = (type_flags & eTypeIsSigned) != 0;
             switch (byte_size)
@@ -637,7 +637,7 @@ ABISysV_ppc64::GetReturnValueObjectSimple (Thread &thread,
             }
             else
             {
-                const size_t byte_size = return_clang_type.GetByteSize();
+                const size_t byte_size = return_clang_type.GetByteSize(nullptr);
                 if (byte_size <= sizeof(long double))
                 {
                     const RegisterInfo *f1_info = reg_ctx->GetRegisterInfoByName("f1", 0);
@@ -681,7 +681,7 @@ ABISysV_ppc64::GetReturnValueObjectSimple (Thread &thread,
     }
     else if (type_flags & eTypeIsVector)
     {
-        const size_t byte_size = return_clang_type.GetByteSize();
+        const size_t byte_size = return_clang_type.GetByteSize(nullptr);
         if (byte_size > 0)
         {
 
@@ -742,7 +742,7 @@ ABISysV_ppc64::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_cl
     if (!reg_ctx_sp)
         return return_valobj_sp;
 
-    const size_t bit_width = return_clang_type.GetBitSize();
+    const size_t bit_width = return_clang_type.GetBitSize(nullptr);
     if (return_clang_type.IsAggregateType())
     {
         Target *target = exe_ctx.GetTargetPtr();
@@ -784,7 +784,7 @@ ABISysV_ppc64::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_cl
                 uint32_t count;
 
                 ClangASTType field_clang_type = return_clang_type.GetFieldAtIndex (idx, name, &field_bit_offset, NULL, NULL);
-                const size_t field_bit_width = field_clang_type.GetBitSize();
+                const size_t field_bit_width = field_clang_type.GetBitSize(nullptr);
 
                 // If there are any unaligned fields, this is stored in memory.
                 if (field_bit_offset % field_bit_width != 0)
diff --git a/lldb/source/Plugins/ABI/SysV-x86_64/ABISysV_x86_64.cpp b/lldb/source/Plugins/ABI/SysV-x86_64/ABISysV_x86_64.cpp
index 4acaa76c690..71d99c8c65d 100644
--- a/lldb/source/Plugins/ABI/SysV-x86_64/ABISysV_x86_64.cpp
+++ b/lldb/source/Plugins/ABI/SysV-x86_64/ABISysV_x86_64.cpp
@@ -510,7 +510,7 @@ ABISysV_x86_64::GetArgumentValues (Thread &thread,
         if (clang_type.IsIntegerType (is_signed))
         {
             ReadIntegerArgument(value->GetScalar(),
-                                clang_type.GetBitSize(),
+                                clang_type.GetBitSize(nullptr),
                                 is_signed,
                                 thread, 
                                 argument_register_ids, 
@@ -520,7 +520,7 @@ ABISysV_x86_64::GetArgumentValues (Thread &thread,
         else if (clang_type.IsPointerType ())
         {
             ReadIntegerArgument(value->GetScalar(),
-                                clang_type.GetBitSize(),
+                                clang_type.GetBitSize(nullptr),
                                 false,
                                 thread,
                                 argument_register_ids, 
@@ -590,7 +590,7 @@ ABISysV_x86_64::SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueOb
             error.SetErrorString ("We don't support returning complex values at present");
         else
         {
-            size_t bit_width = clang_type.GetBitSize();
+            size_t bit_width = clang_type.GetBitSize(nullptr);
             if (bit_width <= 64)
             {
                 const RegisterInfo *xmm0_info = reg_ctx->GetRegisterInfoByName("xmm0", 0);
@@ -658,7 +658,7 @@ ABISysV_x86_64::GetReturnValueObjectSimple (Thread &thread,
         {
             // Extract the register context so we can read arguments from registers
             
-            const size_t byte_size = return_clang_type.GetByteSize();
+            const size_t byte_size = return_clang_type.GetByteSize(nullptr);
             uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned(reg_ctx->GetRegisterInfoByName("rax", 0), 0);
             const bool is_signed = (type_flags & eTypeIsSigned) != 0;
             switch (byte_size)
@@ -707,7 +707,7 @@ ABISysV_x86_64::GetReturnValueObjectSimple (Thread &thread,
             }
             else
             {
-                const size_t byte_size = return_clang_type.GetByteSize();
+                const size_t byte_size = return_clang_type.GetByteSize(nullptr);
                 if (byte_size <= sizeof(long double))
                 {
                     const RegisterInfo *xmm0_info = reg_ctx->GetRegisterInfoByName("xmm0", 0);
@@ -755,7 +755,7 @@ ABISysV_x86_64::GetReturnValueObjectSimple (Thread &thread,
     }
     else if (type_flags & eTypeIsVector)
     {
-        const size_t byte_size = return_clang_type.GetByteSize();
+        const size_t byte_size = return_clang_type.GetByteSize(nullptr);
         if (byte_size > 0)
         {
 
@@ -821,7 +821,7 @@ ABISysV_x86_64::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_c
     if (!reg_ctx_sp)
         return return_valobj_sp;
         
-    const size_t bit_width = return_clang_type.GetBitSize();
+    const size_t bit_width = return_clang_type.GetBitSize(nullptr);
     if (return_clang_type.IsAggregateType())
     {
         Target *target = exe_ctx.GetTargetPtr();
@@ -869,7 +869,7 @@ ABISysV_x86_64::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_c
                 uint32_t count;
                 
                 ClangASTType field_clang_type = return_clang_type.GetFieldAtIndex (idx, name, &field_bit_offset, NULL, NULL);
-                const size_t field_bit_width = field_clang_type.GetBitSize();
+                const size_t field_bit_width = field_clang_type.GetBitSize(nullptr);
 
                 // If there are any unaligned fields, this is stored in memory.
                 if (field_bit_offset % field_bit_width != 0)
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
index e5fa755af58..e2aefd13fee 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -6984,7 +6984,7 @@ SymbolFileDWARF::ParseType (const SymbolContext& sc, DWARFCompileUnit* dwarf_cu,
 
                         clang_type = pointee_clang_type.CreateMemberPointerType(class_clang_type);
 
-                        byte_size = clang_type.GetByteSize();
+                        byte_size = clang_type.GetByteSize(nullptr);
 
                         type_sp.reset( new Type (MakeUserID(die->GetOffset()), 
                                                  this, 
diff --git a/lldb/source/Symbol/ClangASTContext.cpp b/lldb/source/Symbol/ClangASTContext.cpp
index d851ae79218..73f692064b4 100644
--- a/lldb/source/Symbol/ClangASTContext.cpp
+++ b/lldb/source/Symbol/ClangASTContext.cpp
@@ -708,7 +708,7 @@ uint32_t
 ClangASTContext::GetPointerByteSize ()
 {
     if (m_pointer_byte_size == 0)
-        m_pointer_byte_size = GetBasicType(lldb::eBasicTypeVoid).GetPointerType().GetByteSize();
+        m_pointer_byte_size = GetBasicType(lldb::eBasicTypeVoid).GetPointerType().GetByteSize(nullptr);
     return m_pointer_byte_size;
 }
 
diff --git a/lldb/source/Symbol/ClangASTType.cpp b/lldb/source/Symbol/ClangASTType.cpp
index 8b672fac431..4ffeadf3e11 100644
--- a/lldb/source/Symbol/ClangASTType.cpp
+++ b/lldb/source/Symbol/ClangASTType.cpp
@@ -1663,7 +1663,7 @@ ClangASTType::GetArrayElementType (uint64_t *stride) const
         
         // TODO: the real stride will be >= this value.. find the real one!
         if (stride)
-            *stride = element_type.GetByteSize();
+            *stride = element_type.GetByteSize(nullptr);
         
         return element_type;
         
@@ -2062,28 +2062,45 @@ ClangASTType::GetBasicTypeFromAST (lldb::BasicType basic_type) const
 //----------------------------------------------------------------------
 
 uint64_t
-ClangASTType::GetBitSize () const
+ClangASTType::GetBitSize (ExecutionContext *exe_ctx) const
 {
     if (GetCompleteType ())
     {
         clang::QualType qual_type(GetCanonicalQualType());
-        const uint32_t bit_size = m_ast->getTypeSize (qual_type);
-        if (bit_size == 0)
+        switch (qual_type->getTypeClass())
         {
-            if (qual_type->isIncompleteArrayType())
-                return m_ast->getTypeSize (qual_type->getArrayElementTypeNoTypeQual()->getCanonicalTypeUnqualified());
+            case clang::Type::ObjCInterface:
+            case clang::Type::ObjCObject:
+                if (exe_ctx && exe_ctx->GetProcessPtr())
+                {
+                    ObjCLanguageRuntime *objc_runtime = exe_ctx->GetProcessPtr()->GetObjCLanguageRuntime();
+                    if (objc_runtime)
+                    {
+                        uint64_t bit_size = 0;
+                        if (objc_runtime->GetTypeBitSize(*this, bit_size))
+                            return bit_size;
+                    }
+                }
+                // fallthrough
+            default:
+                const uint32_t bit_size = m_ast->getTypeSize (qual_type);
+                if (bit_size == 0)
+                {
+                    if (qual_type->isIncompleteArrayType())
+                        return m_ast->getTypeSize (qual_type->getArrayElementTypeNoTypeQual()->getCanonicalTypeUnqualified());
+                }
+                if (qual_type->isObjCObjectOrInterfaceType())
+                    return bit_size + m_ast->getTypeSize(m_ast->ObjCBuiltinClassTy);
+                return bit_size;
         }
-        if (qual_type->isObjCObjectOrInterfaceType())
-            return bit_size + m_ast->getTypeSize(m_ast->ObjCBuiltinClassTy);
-        return bit_size;
     }
     return 0;
 }
 
 uint64_t
-ClangASTType::GetByteSize () const
+ClangASTType::GetByteSize (ExecutionContext *exe_ctx) const
 {
-    return (GetBitSize () + 7) / 8;
+    return (GetBitSize (exe_ctx) + 7) / 8;
 }
 
 size_t
@@ -3416,7 +3433,7 @@ ClangASTType::GetChildClangTypeAtIndex (ExecutionContext *exe_ctx,
                             child_byte_offset = bit_offset/8;
                             ClangASTType base_class_clang_type(m_ast, base_class->getType());
                             child_name = base_class_clang_type.GetTypeName().AsCString("");
-                            uint64_t base_class_clang_type_bit_size = base_class_clang_type.GetBitSize();
+                            uint64_t base_class_clang_type_bit_size = base_class_clang_type.GetBitSize(nullptr);
                             
                             // Base classes bit sizes should be a multiple of 8 bits in size
                             assert (base_class_clang_type_bit_size % 8 == 0);
@@ -3444,7 +3461,7 @@ ClangASTType::GetChildClangTypeAtIndex (ExecutionContext *exe_ctx,
                         // alignment (field_type_info.second) from the AST context.
                         ClangASTType field_clang_type (m_ast, field->getType());
                         assert(field_idx < record_layout.getFieldCount());
-                        child_byte_size = field_clang_type.GetByteSize();
+                        child_byte_size = field_clang_type.GetByteSize(nullptr);
                         
                         // Figure out the field offset within the current struct/union/class type
                         bit_offset = record_layout.getFieldOffset (field_idx);
@@ -3609,7 +3626,7 @@ ClangASTType::GetChildClangTypeAtIndex (ExecutionContext *exe_ctx,
                     // We have a pointer to an simple type
                     if (idx == 0 && pointee_clang_type.GetCompleteType())
                     {
-                        child_byte_size = pointee_clang_type.GetByteSize();
+                        child_byte_size = pointee_clang_type.GetByteSize(nullptr);
                         child_byte_offset = 0;
                         return pointee_clang_type;
                     }
@@ -3630,7 +3647,7 @@ ClangASTType::GetChildClangTypeAtIndex (ExecutionContext *exe_ctx,
                         char element_name[64];
                         ::snprintf (element_name, sizeof (element_name), "[%zu]", idx);
                         child_name.assign(element_name);
-                        child_byte_size = element_type.GetByteSize();
+                        child_byte_size = element_type.GetByteSize(nullptr);
                         child_byte_offset = (int32_t)idx * (int32_t)child_byte_size;
                         return element_type;
                     }
@@ -3651,7 +3668,7 @@ ClangASTType::GetChildClangTypeAtIndex (ExecutionContext *exe_ctx,
                         char element_name[64];
                         ::snprintf (element_name, sizeof (element_name), "[%zu]", idx);
                         child_name.assign(element_name);
-                        child_byte_size = element_type.GetByteSize();
+                        child_byte_size = element_type.GetByteSize(nullptr);
                         child_byte_offset = (int32_t)idx * (int32_t)child_byte_size;
                         return element_type;
                     }
@@ -3701,7 +3718,7 @@ ClangASTType::GetChildClangTypeAtIndex (ExecutionContext *exe_ctx,
                     // We have a pointer to an simple type
                     if (idx == 0)
                     {
-                        child_byte_size = pointee_clang_type.GetByteSize();
+                        child_byte_size = pointee_clang_type.GetByteSize(nullptr);
                         child_byte_offset = 0;
                         return pointee_clang_type;
                     }
@@ -3745,7 +3762,7 @@ ClangASTType::GetChildClangTypeAtIndex (ExecutionContext *exe_ctx,
                     // We have a pointer to an simple type
                     if (idx == 0)
                     {
-                        child_byte_size = pointee_clang_type.GetByteSize();
+                        child_byte_size = pointee_clang_type.GetByteSize(nullptr);
                         child_byte_offset = 0;
                         return pointee_clang_type;
                     }
@@ -6643,7 +6660,7 @@ ClangASTType::GetValueAsScalar (const lldb_private::DataExtractor &data,
         if (encoding == lldb::eEncodingInvalid || count != 1)
             return false;
 
-        const uint64_t byte_size = GetByteSize();
+        const uint64_t byte_size = GetByteSize(nullptr);
         lldb::offset_t offset = data_byte_offset;
         switch (encoding)
         {
@@ -6771,7 +6788,7 @@ ClangASTType::SetValueFromScalar (const Scalar &value, Stream &strm)
         if (encoding == lldb::eEncodingInvalid || count != 1)
             return false;
 
-        const uint64_t bit_width = GetBitSize();
+        const uint64_t bit_width = GetBitSize(nullptr);
         // This function doesn't currently handle non-byte aligned assignments
         if ((bit_width % 8) != 0)
             return false;
@@ -6851,7 +6868,7 @@ ClangASTType::ReadFromMemory (lldb_private::ExecutionContext *exe_ctx,
     if (!GetCompleteType())
         return false;
     
-    const uint64_t byte_size = GetByteSize();
+    const uint64_t byte_size = GetByteSize(nullptr);
     if (data.GetByteSize() < byte_size)
     {
         lldb::DataBufferSP data_sp(new DataBufferHeap (byte_size, '\0'));
@@ -6901,7 +6918,7 @@ ClangASTType::WriteToMemory (lldb_private::ExecutionContext *exe_ctx,
     if (!GetCompleteType())
         return false;
 
-    const uint64_t byte_size = GetByteSize();
+    const uint64_t byte_size = GetByteSize(nullptr);
 
     if (byte_size > 0)
     {
diff --git a/lldb/source/Symbol/Type.cpp b/lldb/source/Symbol/Type.cpp
index 210cd509016..6e67f4695d9 100644
--- a/lldb/source/Symbol/Type.cpp
+++ b/lldb/source/Symbol/Type.cpp
@@ -336,7 +336,7 @@ Type::GetByteSize()
                 if (encoding_type)
                     m_byte_size = encoding_type->GetByteSize();
                 if (m_byte_size == 0)
-                    m_byte_size = GetClangLayoutType().GetByteSize();
+                    m_byte_size = GetClangLayoutType().GetByteSize(nullptr);
             }
             break;