addressing comments

Author: joaosaffran

llvm/include/llvm/BinaryFormat/DXContainer.h

@@ -585,8 +585,8 @@ struct ProgramSignatureElement {
 
 static_assert(sizeof(ProgramSignatureElement) == 32,
               "ProgramSignatureElement is misaligned");
-namespace RST0 {
-namespace v0 {
+namespace RTS0 {
+namespace v1 {
 struct RootDescriptor {
   uint32_t ShaderRegister;
   uint32_t RegisterSpace;
@@ -595,18 +595,23 @@ struct RootDescriptor {
     sys::swapByteOrder(RegisterSpace);
   }
 };
-} // namespace v0
+} // namespace v1
 
-namespace v1 {
-struct RootDescriptor : public v0::RootDescriptor {
+namespace v2 {
+struct RootDescriptor : public v1::RootDescriptor {
   uint32_t Flags;
+
+  RootDescriptor() = default;
+  RootDescriptor(v1::RootDescriptor &Base)
+      : v1::RootDescriptor(Base), Flags(0u) {}
+
   void swapBytes() {
-    v0::RootDescriptor::swapBytes();
+    v1::RootDescriptor::swapBytes();
     sys::swapByteOrder(Flags);
   }
 };
-} // namespace v1
-} // namespace RST0
+} // namespace v2
+} // namespace RTS0
 // following dx12 naming
 // https://learn.microsoft.com/en-us/windows/win32/api/d3d12/ns-d3d12-d3d12_root_constants
 struct RootConstants {

llvm/include/llvm/MC/DXContainerRootSignature.h

@@ -19,7 +19,7 @@ struct RootParameter {
   dxbc::RootParameterHeader Header;
   union {
     dxbc::RootConstants Constants;
-    dxbc::RST0::v1::RootDescriptor Descriptor;
+    dxbc::RTS0::v2::RootDescriptor Descriptor;
   };
 };
 struct RootSignatureDesc {

llvm/include/llvm/Object/DXContainer.h

@@ -17,6 +17,7 @@
 
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Twine.h"
 #include "llvm/BinaryFormat/DXContainer.h"
 #include "llvm/Object/Error.h"
 #include "llvm/Support/Error.h"
@@ -124,16 +125,13 @@ struct RootParameterView {
   RootParameterView(uint32_t V, const dxbc::RootParameterHeader &H, StringRef P)
       : Header(H), ParamData(P) {}
 
-  template <typename T, typename VersionT = T> Expected<T> readParameter() {
-    assert(sizeof(VersionT) <= sizeof(T) &&
-           "Parameter of higher version must inherit all previous version data "
-           "members");
-    if (sizeof(VersionT) != ParamData.size())
+  template <typename T> Expected<T> readParameter() {
+    if (sizeof(T) != ParamData.size())
       return make_error<GenericBinaryError>(
           "Reading structure out of file bounds", object_error::parse_failed);
 
     T Struct;
-    memcpy(&Struct, ParamData.data(), sizeof(VersionT));
+    memcpy(&Struct, ParamData.data(), sizeof(T));
     // DXContainer is always little endian
     if (sys::IsBigEndianHost)
       Struct.swapBytes();
@@ -162,11 +160,18 @@ struct RootDescriptorView : RootParameterView {
                 llvm::to_underlying(dxbc::RootParameterType::UAV));
   }
 
-  llvm::Expected<dxbc::RST0::v1::RootDescriptor> read(uint32_t Version) {
-    if (Version == 1)
-      return readParameter<dxbc::RST0::v1::RootDescriptor,
-                           dxbc::RST0::v0::RootDescriptor>();
-    return readParameter<dxbc::RST0::v1::RootDescriptor>();
+  llvm::Expected<dxbc::RTS0::v2::RootDescriptor> read(uint32_t Version) {
+    if (Version == 1) {
+      auto Descriptor = readParameter<dxbc::RTS0::v1::RootDescriptor>();
+      if (Error E = Descriptor.takeError())
+        return E;
+      return dxbc::RTS0::v2::RootDescriptor(*Descriptor);
+    }
+    if (Version != 2)
+      return make_error<GenericBinaryError>("Invalid Root Signature version: " +
+                                                Twine(Version),
+                                            object_error::parse_failed);
+    return readParameter<dxbc::RTS0::v2::RootDescriptor>();
   }
 };
 
@@ -217,9 +222,9 @@ class RootSignature {
     case dxbc::RootParameterType::SRV:
     case dxbc::RootParameterType::UAV:
       if (Version == 1)
-        DataSize = sizeof(dxbc::RST0::v0::RootDescriptor);
+        DataSize = sizeof(dxbc::RTS0::v1::RootDescriptor);
       else
-        DataSize = sizeof(dxbc::RST0::v1::RootDescriptor);
+        DataSize = sizeof(dxbc::RTS0::v2::RootDescriptor);
       break;
     }
     size_t EndOfSectionByte = getNumStaticSamplers() == 0

llvm/include/llvm/ObjectYAML/DXContainerYAML.h

@@ -95,7 +95,7 @@ struct RootParameterYamlDesc {
   uint32_t Type;
   uint32_t Visibility;
   uint32_t Offset;
-  RootParameterYamlDesc(){};
+  RootParameterYamlDesc() {};
   RootParameterYamlDesc(uint32_t T) : Type(T) {
     switch (T) {
 

llvm/lib/MC/DXContainerRootSignature.cpp

@@ -41,9 +41,9 @@ size_t RootSignatureDesc::getSize() const {
     case llvm::to_underlying(dxbc::RootParameterType::SRV):
     case llvm::to_underlying(dxbc::RootParameterType::UAV):
       if (Version == 1)
-        Size += sizeof(dxbc::RST0::v0::RootDescriptor);
+        Size += sizeof(dxbc::RTS0::v1::RootDescriptor);
       else
-        Size += sizeof(dxbc::RST0::v1::RootDescriptor);
+        Size += sizeof(dxbc::RTS0::v2::RootDescriptor);
 
       break;
     }

llvm/lib/ObjectYAML/DXContainerYAML.cpp

@@ -82,7 +82,7 @@ DXContainerYAML::RootSignatureYamlDesc::create(
       NewP.Constants.RegisterSpace = Constants.RegisterSpace;
     } else if (auto *RDV =
                    dyn_cast<object::DirectX::RootDescriptorView>(&ParamView)) {
-      llvm::Expected<dxbc::RST0::v1::RootDescriptor> DescriptorOrErr =
+      llvm::Expected<dxbc::RTS0::v2::RootDescriptor> DescriptorOrErr =
           RDV->read(Version);
       if (Error E = DescriptorOrErr.takeError())
         return std::move(E);