HitGroup subobject changes (#1688)

- Replace HitGroup subobject by TriangleHitGroup and ProcedurePrimitiveHitGroup - Add internal HitGroupType enum that maps to D3D12_HIT_GROUP_TYPE - Add corresponding HitGroupType field to metadata, RDAT and reflection
2018-11-09 17:50:04 -08:00 · 2018-11-09 17:50:04 -08:00 · d75f96aabb
--- a/include/dxc/DXIL/DxilConstants.h
+++ b/include/dxc/DXIL/DxilConstants.h
@ -1157,6 +1157,7 @@ namespace DXIL {
    HitGroup                          = 11,
    NumKinds // aka D3D12_STATE_SUBOBJECT_TYPE_MAX_VALID
  };
+
  inline bool IsValidSubobjectKind(SubobjectKind kind) {
    return (kind < SubobjectKind::NumKinds &&
      ( kind <= SubobjectKind::LocalRootSignature ||
@ -1169,6 +1170,16 @@ namespace DXIL {
    ValidMask = 0x3,
  };

+  enum class HitGroupType : uint32_t {
+    Triangle = 0x0,
+    ProceduralPrimitive = 0x1,
+    LastEntry,
+  };
+
+  inline bool IsValidHitGroupType(HitGroupType type) {
+    return (type >= HitGroupType::Triangle && type < HitGroupType::LastEntry);
+  }
+
  extern const char* kLegacyLayoutString;
  extern const char* kNewLayoutString;
  extern const char* kFP32DenormKindString;
--- a/include/dxc/DXIL/DxilSubobject.h
+++ b/include/dxc/DXIL/DxilSubobject.h
@ -50,7 +50,8 @@ public:
  bool GetRaytracingShaderConfig(uint32_t &MaxPayloadSizeInBytes,
                                 uint32_t &MaxAttributeSizeInBytes) const;
  bool GetRaytracingPipelineConfig(uint32_t &MaxTraceRecursionDepth) const;
-  bool GetHitGroup(llvm::StringRef &AnyHit,
+  bool GetHitGroup(DXIL::HitGroupType &hitGroupType,
+                   llvm::StringRef &AnyHit,
                   llvm::StringRef &ClosestHit,
                   llvm::StringRef &Intersection) const;

@ -86,6 +87,7 @@ private:
    uint32_t MaxTraceRecursionDepth;
  };
  struct HitGroup_t {
+    DXIL::HitGroupType Type;
    const char *AnyHit;
    const char *ClosestHit;
    const char *Intersection;
@ -147,7 +149,8 @@ public:
  DxilSubobject &CreateRaytracingPipelineConfig(
    llvm::StringRef Name,
    uint32_t MaxTraceRecursionDepth);
-  DxilSubobject &CreateHitGroup(llvm::StringRef Name,
+  DxilSubobject &CreateHitGroup(llvm::StringRef Name, 
+                                DXIL::HitGroupType hitGroupType,
                                llvm::StringRef AnyHit,
                                llvm::StringRef ClosestHit,
                                llvm::StringRef Intersection);
--- a/include/dxc/DxilContainer/DxilRuntimeReflection.h
+++ b/include/dxc/DxilContainer/DxilRuntimeReflection.h
@ -212,6 +212,7 @@ struct RuntimeDataSubobjectInfo {
    uint32_t MaxTraceRecursionDepth;
  };
  struct HitGroup_t {
+    uint32_t Type;
    // each is a string table offset for the shader name
    // 0 points to empty name, indicating no shader.
    uint32_t AnyHit;
@ -532,6 +533,10 @@ public:
  }

  // HitGroup
+  DXIL::HitGroupType GetHitGroup_Type() const {
+    return (GetKind() == DXIL::SubobjectKind::HitGroup) ?
+      (DXIL::HitGroupType)m_SubobjectInfo->HitGroup.Type : (DXIL::HitGroupType)(-1);
+  }
  const char *GetHitGroup_Intersection() const {
    return (GetKind() == DXIL::SubobjectKind::HitGroup) ?
      m_Context->pStringTableReader->Get(m_SubobjectInfo->HitGroup.Intersection) : "";
@ -643,6 +648,7 @@ struct DxilSubobjectDesc {
    uint32_t MaxTraceRecursionDepth;
  };
  struct HitGroup_t {
+    uint32_t Type;  // DXIL::HitGroupType / D3D12_HIT_GROUP_TYPE
    LPCWSTR AnyHit;
    LPCWSTR ClosestHit;
    LPCWSTR Intersection;
--- a/lib/DXIL/DxilMetadataHelper.cpp
+++ b/lib/DXIL/DxilMetadataHelper.cpp
@ -1412,8 +1412,10 @@ Metadata *DxilMDHelper::EmitSubobject(const DxilSubobject &obj) {
  }
  case DXIL::SubobjectKind::HitGroup: {
    llvm::StringRef Intersection, AnyHit, ClosestHit;
-    IFTBOOL(obj.GetHitGroup(Intersection, AnyHit, ClosestHit),
+    DXIL::HitGroupType hgType;
+    IFTBOOL(obj.GetHitGroup(hgType, Intersection, AnyHit, ClosestHit),
      DXC_E_INCORRECT_DXIL_METADATA);
+    Args.emplace_back(Uint32ToConstMD((uint32_t)hgType));
    Args.emplace_back(MDString::get(m_Ctx, Intersection));
    Args.emplace_back(MDString::get(m_Ctx, AnyHit));
    Args.emplace_back(MDString::get(m_Ctx, ClosestHit));
@ -1481,10 +1483,11 @@ void DxilMDHelper::LoadSubobject(const llvm::MDNode &MD, DxilSubobjects &Subobje
    break;
  }
  case DXIL::SubobjectKind::HitGroup: {
+    uint32_t hgType = ConstMDToUint32(MD.getOperand(i++));
    StringRef Intersection(StringMDToStringRef(MD.getOperand(i++)));
    StringRef AnyHit(StringMDToStringRef(MD.getOperand(i++)));
    StringRef ClosestHit(StringMDToStringRef(MD.getOperand(i++)));
-    Subobjects.CreateHitGroup(name, AnyHit, ClosestHit, Intersection);
+    Subobjects.CreateHitGroup(name, (DXIL::HitGroupType)hgType, AnyHit, ClosestHit, Intersection);
    break;
  }
  default:
--- a/lib/DXIL/DxilSubobject.cpp
+++ b/lib/DXIL/DxilSubobject.cpp
@ -71,6 +71,7 @@ void DxilSubobject::CopyUnionedContents(const DxilSubobject &other) {
    RaytracingPipelineConfig.MaxTraceRecursionDepth = other.RaytracingPipelineConfig.MaxTraceRecursionDepth;
    break;
  case Kind::HitGroup:
+    HitGroup.Type = other.HitGroup.Type;
    HitGroup.AnyHit = other.HitGroup.AnyHit;
    HitGroup.ClosestHit = other.HitGroup.ClosestHit;
    HitGroup.Intersection = other.HitGroup.Intersection;
@ -160,10 +161,12 @@ bool DxilSubobject::GetRaytracingPipelineConfig(
 }

 // HitGroup
-bool DxilSubobject::GetHitGroup(llvm::StringRef &AnyHit,
+bool DxilSubobject::GetHitGroup(DXIL::HitGroupType &hitGroupType, 
+                                llvm::StringRef &AnyHit,
                                llvm::StringRef &ClosestHit,
                                llvm::StringRef &Intersection) const {
  if (m_Kind == Kind::HitGroup) {
+    hitGroupType = HitGroup.Type;
    AnyHit = HitGroup.AnyHit;
    ClosestHit = HitGroup.ClosestHit;
    Intersection = HitGroup.Intersection;
@ -291,6 +294,7 @@ DxilSubobject &DxilSubobjects::CreateRaytracingPipelineConfig(
 }

 DxilSubobject &DxilSubobjects::CreateHitGroup(llvm::StringRef Name,
+                                              DXIL::HitGroupType hitGroupType,
                                              llvm::StringRef AnyHit,
                                              llvm::StringRef ClosestHit,
                                              llvm::StringRef Intersection) {
@ -298,6 +302,7 @@ DxilSubobject &DxilSubobjects::CreateHitGroup(llvm::StringRef Name,
  AnyHit = GetSubobjectString(AnyHit);
  ClosestHit = GetSubobjectString(ClosestHit);
  Intersection = GetSubobjectString(Intersection);
+  obj.HitGroup.Type = hitGroupType;
  obj.HitGroup.AnyHit = AnyHit.data();
  obj.HitGroup.ClosestHit = ClosestHit.data();
  obj.HitGroup.Intersection = Intersection.data();
--- a/lib/DxilContainer/DxilContainerAssembler.cpp
+++ b/lib/DxilContainer/DxilContainerAssembler.cpp
@ -1243,10 +1243,12 @@ private:
          info.RaytracingPipelineConfig.MaxTraceRecursionDepth);
        break;
      case DXIL::SubobjectKind::HitGroup:
+        HitGroupType hgType;
        StringRef AnyHit;
        StringRef ClosestHit;
        StringRef Intersection;
-        obj.GetHitGroup(AnyHit, ClosestHit, Intersection);
+        obj.GetHitGroup(hgType, AnyHit, ClosestHit, Intersection);
+        info.HitGroup.Type = (uint32_t)hgType;
        info.HitGroup.AnyHit = m_pStringBufferPart->Insert(AnyHit);
        info.HitGroup.ClosestHit = m_pStringBufferPart->Insert(ClosestHit);
        info.HitGroup.Intersection = m_pStringBufferPart->Insert(Intersection);
--- a/lib/DxilContainer/DxilContainerReader.cpp
+++ b/lib/DxilContainer/DxilContainerReader.cpp
@ -62,6 +62,7 @@ void LoadSubobjectsFromRDAT(DxilSubobjects &subobjects, RDAT::SubobjectTableRead
      break;
    case DXIL::SubobjectKind::HitGroup:
      subobjects.CreateHitGroup(reader.GetName(),
+        reader.GetHitGroup_Type(),
        reader.GetHitGroup_AnyHit(),
        reader.GetHitGroup_ClosestHit(),
        reader.GetHitGroup_Intersection());
--- a/tools/clang/include/clang/AST/HlslTypes.h
+++ b/tools/clang/include/clang/AST/HlslTypes.h
@ -390,7 +390,8 @@ clang::QualType GetHLSLOutputPatchElementType(clang::QualType type);
 unsigned GetHLSLOutputPatchCount(clang::QualType type);

 bool IsHLSLSubobjectType(clang::QualType type);
-bool GetHLSLSubobjectKind(clang::QualType type, DXIL::SubobjectKind &subobjectKind);
+bool GetHLSLSubobjectKind(clang::QualType type, DXIL::SubobjectKind &subobjectKind, 
+                          DXIL::HitGroupType &ghType);

 bool IsArrayConstantStringType(const clang::QualType type);
 bool IsPointerStringType(const clang::QualType type);
--- a/tools/clang/lib/AST/HlslTypes.cpp
+++ b/tools/clang/lib/AST/HlslTypes.cpp
@ -503,10 +503,12 @@ bool IsHLSLResourceType(clang::QualType type) {

 bool IsHLSLSubobjectType(clang::QualType type) {
  DXIL::SubobjectKind kind;
-  return GetHLSLSubobjectKind(type, kind);
+  DXIL::HitGroupType hgType;
+  return GetHLSLSubobjectKind(type, kind, hgType);
 }

-bool GetHLSLSubobjectKind(clang::QualType type, DXIL::SubobjectKind &subobjectKind) {
+bool GetHLSLSubobjectKind(clang::QualType type, DXIL::SubobjectKind &subobjectKind, DXIL::HitGroupType &hgType) {
+  hgType = (DXIL::HitGroupType)(-1);
  type = type.getCanonicalType();
  if (const RecordType *RT = type->getAs<RecordType>()) {
    StringRef name = RT->getDecl()->getName();
@ -523,8 +525,20 @@ bool GetHLSLSubobjectKind(clang::QualType type, DXIL::SubobjectKind &subobjectKi
      return name == "RaytracingShaderConfig" ? (subobjectKind = DXIL::SubobjectKind::RaytracingShaderConfig, true) : false;
    case 24:
      return name == "RaytracingPipelineConfig" ? (subobjectKind = DXIL::SubobjectKind::RaytracingPipelineConfig, true) : false;
-    case 8:
-      return name == "HitGroup" ? (subobjectKind = DXIL::SubobjectKind::HitGroup, true) : false;
+    case 16:
+      if (name == "TriangleHitGroup") {
+        subobjectKind = DXIL::SubobjectKind::HitGroup;
+        hgType = DXIL::HitGroupType::Triangle;
+        return true;
+      }
+      return false;
+    case 27:
+      if (name == "ProceduralPrimitiveHitGroup") {
+        subobjectKind = DXIL::SubobjectKind::HitGroup;
+        hgType = DXIL::HitGroupType::ProceduralPrimitive;
+        return true;
+      }
+      return false;
    }
  }
  return false;
--- a/tools/clang/lib/CodeGen/CGHLSLMS.cpp
+++ b/tools/clang/lib/CodeGen/CGHLSLMS.cpp
@ -120,8 +120,8 @@ private:
  uint32_t AddCBuffer(HLSLBufferDecl *D);
  hlsl::DxilResourceBase::Class TypeToClass(clang::QualType Ty);

-  void CreateSubobject(DXIL::SubobjectKind kind, const StringRef name,
-                       clang::Expr **args, unsigned int argCount);
+  void CreateSubobject(DXIL::SubobjectKind kind, const StringRef name, clang::Expr **args,
+                       unsigned int argCount, DXIL::HitGroupType hgType = (DXIL::HitGroupType)(-1));
  bool GetAsConstantString(clang::Expr *expr, StringRef *value, bool failWhenEmpty = false);
  bool GetAsConstantUInt32(clang::Expr *expr, uint32_t *value);
  std::vector<StringRef> ParseSubobjectExportsAssociations(StringRef exports);
@ -2218,7 +2218,8 @@ void CGMSHLSLRuntime::addSubobject(Decl *D) {
  DXASSERT(VD != nullptr, "must be a global variable");
 
  DXIL::SubobjectKind subobjKind;
-  if (!hlsl::GetHLSLSubobjectKind(VD->getType(), subobjKind)) {
+  DXIL::HitGroupType hgType;
+  if (!hlsl::GetHLSLSubobjectKind(VD->getType(), subobjKind, hgType)) {
    DXASSERT(false, "not a valid subobject declaration");
    return;
  }
@ -2232,7 +2233,7 @@ void CGMSHLSLRuntime::addSubobject(Decl *D) {
  }

  if (InitListExpr *initListExpr = dyn_cast<InitListExpr>(initExpr)) {
-    CreateSubobject(subobjKind, VD->getName(), initListExpr->getInits(), initListExpr->getNumInits());
+    CreateSubobject(subobjKind, VD->getName(), initListExpr->getInits(), initListExpr->getNumInits(), hgType);
  }
  else {
    DiagnosticsEngine &Diags = CGM.getDiags();
@ -2458,7 +2459,8 @@ std::vector<StringRef> CGMSHLSLRuntime::ParseSubobjectExportsAssociations(String


 void CGMSHLSLRuntime::CreateSubobject(DXIL::SubobjectKind kind, const StringRef name,
-                                      clang::Expr **args, unsigned int argCount) {
+                                      clang::Expr **args, unsigned int argCount,
+                                      DXIL::HitGroupType hgType /*= (DXIL::HitGroupType)(-1)*/) {
  DxilSubobjects *subobjects = m_pHLModule->GetSubobjects();
  if (!subobjects) {
    subobjects = new DxilSubobjects();
@ -2526,13 +2528,29 @@ void CGMSHLSLRuntime::CreateSubobject(DXIL::SubobjectKind kind, const StringRef
      break;
    }
    case DXIL::SubobjectKind::HitGroup: {
-      DXASSERT_NOMSG(argCount == 3);
-      StringRef anyhit, closesthit, intersection;
-      if (!GetAsConstantString(args[0], &anyhit) ||
-          !GetAsConstantString(args[1], &closesthit) ||
-          !GetAsConstantString(args[2], &intersection))
-        return;
-      subobjects->CreateHitGroup(name, anyhit, closesthit, intersection);
+      switch (hgType) {
+        case DXIL::HitGroupType::Triangle: {
+          DXASSERT_NOMSG(argCount == 2);
+          StringRef anyhit, closesthit;
+          if (!GetAsConstantString(args[0], &anyhit) ||
+            !GetAsConstantString(args[1], &closesthit))
+            return;
+          subobjects->CreateHitGroup(name, DXIL::HitGroupType::Triangle, anyhit, closesthit, llvm::StringRef(""));
+          break;
+        }
+        case DXIL::HitGroupType::ProceduralPrimitive: {
+          DXASSERT_NOMSG(argCount == 3);
+          StringRef anyhit, closesthit, intersection;
+          if (!GetAsConstantString(args[0], &anyhit) ||
+              !GetAsConstantString(args[1], &closesthit) ||
+              !GetAsConstantString(args[2], &intersection, true))
+            return;
+          subobjects->CreateHitGroup(name, DXIL::HitGroupType::ProceduralPrimitive, anyhit, closesthit, intersection);
+          break;
+        }
+        default:
+          llvm_unreachable("unknown HitGroupType");
+      }
      break;
    }
    default:
--- a/tools/clang/lib/Sema/SemaHLSL.cpp
+++ b/tools/clang/lib/Sema/SemaHLSL.cpp
@ -196,7 +196,8 @@ enum ArBasicKind {
  AR_OBJECT_SUBOBJECT_TO_EXPORTS_ASSOC,
  AR_OBJECT_RAYTRACING_SHADER_CONFIG,
  AR_OBJECT_RAYTRACING_PIPELINE_CONFIG,
-  AR_OBJECT_HIT_GROUP,
+  AR_OBJECT_TRIANGLE_HIT_GROUP,
+  AR_OBJECT_PROCEDURAL_PRIMITIVE_HIT_GROUP,

  AR_BASIC_MAXIMUM_COUNT
 };
@ -472,8 +473,9 @@ const UINT g_uBasicKindProps[] =
  0,      //AR_OBJECT_SUBOBJECT_TO_EXPORTS_ASSOC,
  0,      //AR_OBJECT_RAYTRACING_SHADER_CONFIG,
  0,      //AR_OBJECT_RAYTRACING_PIPELINE_CONFIG,
-  0,      //AR_OBJECT_HIT_GROUP,
-    
+  0,      //AR_OBJECT_TRIANGLE_HIT_GROUP,
+  0,      //AR_OBJECT_PROCEDURAL_PRIMITIVE_HIT_GROUP,
+
  // AR_BASIC_MAXIMUM_COUNT
 };

@ -1283,7 +1285,8 @@ const ArBasicKind g_ArBasicKindsAsTypes[] =
  AR_OBJECT_SUBOBJECT_TO_EXPORTS_ASSOC,
  AR_OBJECT_RAYTRACING_SHADER_CONFIG,
  AR_OBJECT_RAYTRACING_PIPELINE_CONFIG,
-  AR_OBJECT_HIT_GROUP,
+  AR_OBJECT_TRIANGLE_HIT_GROUP,
+  AR_OBJECT_PROCEDURAL_PRIMITIVE_HIT_GROUP
 };

 // Count of template arguments for basic kind of objects that look like templates (one or more type arguments).
@ -1361,7 +1364,8 @@ const uint8_t g_ArBasicKindsTemplateCount[] =
  0, // AR_OBJECT_SUBOBJECT_TO_EXPORTS_ASSOC,
  0, // AR_OBJECT_RAYTRACING_SHADER_CONFIG,
  0, // AR_OBJECT_RAYTRACING_PIPELINE_CONFIG,
-  0, // AR_OBJECT_HIT_GROUP,
+  0, // AR_OBJECT_TRIANGLE_HIT_GROUP,
+  0, // AR_OBJECT_PROCEDURAL_PRIMITIVE_HIT_GROUP,
 };

 C_ASSERT(_countof(g_ArBasicKindsAsTypes) == _countof(g_ArBasicKindsTemplateCount));
@ -1449,7 +1453,9 @@ const SubscriptOperatorRecord g_ArBasicKindsSubscripts[] =
  { 0, MipsFalse, SampleFalse },  // AR_OBJECT_SUBOBJECT_TO_EXPORTS_ASSOC,
  { 0, MipsFalse, SampleFalse },  // AR_OBJECT_RAYTRACING_SHADER_CONFIG,
  { 0, MipsFalse, SampleFalse },  // AR_OBJECT_RAYTRACING_PIPELINE_CONFIG,
-  { 0, MipsFalse, SampleFalse },  // AR_OBJECT_HIT_GROUP,
+  { 0, MipsFalse, SampleFalse },  // AR_OBJECT_TRIANGLE_HIT_GROUP,
+  { 0, MipsFalse, SampleFalse },  // AR_OBJECT_PROCEDURAL_PRIMITIVE_HIT_GROUP,
+
 };

 C_ASSERT(_countof(g_ArBasicKindsAsTypes) == _countof(g_ArBasicKindsSubscripts));
@ -1561,7 +1567,8 @@ const char* g_ArBasicTypeNames[] =
  "SubobjectToExportsAssociation", 
  "RaytracingShaderConfig",
  "RaytracingPipelineConfig",
-  "HitGroup",
+  "TriangleHitGroup",
+  "ProceduralPrimitiveHitGroup"
 };

 C_ASSERT(_countof(g_ArBasicTypeNames) == AR_BASIC_MAXIMUM_COUNT);
@ -2529,16 +2536,29 @@ static CXXRecordDecl *CreateSubobjectRaytracingPipelineConfig(ASTContext& contex
  return decl;
 }

-// struct HitGroup
+// struct TriangleHitGroup
 // {
-//   string anyhit;
-//   string closesthit;
-//   string intersection;
+//   string AnyHit;
+//   string ClosestHit;
 // };
-static CXXRecordDecl *CreateSubobjectHitGroup(ASTContext& context) {
-  CXXRecordDecl *decl = StartSubobjectDecl(context, "HitGroup");
+static CXXRecordDecl *CreateSubobjectTriangleHitGroup(ASTContext& context) {
+  CXXRecordDecl *decl = StartSubobjectDecl(context, "TriangleHitGroup");
  CreateSimpleField(context, decl, "AnyHit",       context.HLSLStringTy, AccessSpecifier::AS_private);
  CreateSimpleField(context, decl, "ClosestHit",   context.HLSLStringTy, AccessSpecifier::AS_private);
+  FinishSubobjectDecl(context, decl);
+  return decl;
+}
+
+// struct ProceduralPrimitiveHitGroup
+// {
+//   string AnyHit;
+//   string ClosestHit;
+//   string Intersection;
+// };
+static CXXRecordDecl *CreateSubobjectProceduralPrimitiveHitGroup(ASTContext& context) {
+  CXXRecordDecl *decl = StartSubobjectDecl(context, "ProceduralPrimitiveHitGroup");
+  CreateSimpleField(context, decl, "AnyHit", context.HLSLStringTy, AccessSpecifier::AS_private);
+  CreateSimpleField(context, decl, "ClosestHit", context.HLSLStringTy, AccessSpecifier::AS_private);
  CreateSimpleField(context, decl, "Intersection", context.HLSLStringTy, AccessSpecifier::AS_private);
  FinishSubobjectDecl(context, decl);
  return decl;
@ -3189,8 +3209,11 @@ private:
        case AR_OBJECT_RAYTRACING_PIPELINE_CONFIG:
          recordDecl = CreateSubobjectRaytracingPipelineConfig(*m_context);
          break;
-        case AR_OBJECT_HIT_GROUP:
-          recordDecl = CreateSubobjectHitGroup(*m_context);
+        case AR_OBJECT_TRIANGLE_HIT_GROUP:
+          recordDecl = CreateSubobjectTriangleHitGroup(*m_context);
+          break;
+        case AR_OBJECT_PROCEDURAL_PRIMITIVE_HIT_GROUP:
+          recordDecl = CreateSubobjectProceduralPrimitiveHitGroup(*m_context);
          break;
        }
      }
@ -3386,7 +3409,7 @@ public:
  }

  static bool IsSubobjectBasicKind(ArBasicKind kind) {
-    return kind >= AR_OBJECT_STATE_OBJECT_CONFIG && kind <= AR_OBJECT_HIT_GROUP;
+    return kind >= AR_OBJECT_STATE_OBJECT_CONFIG && kind <= AR_OBJECT_PROCEDURAL_PRIMITIVE_HIT_GROUP;
  }

  bool IsSubobjectType(QualType type) {
--- a/tools/clang/test/CodeGenHLSL/quick-test/subobjects.hlsl
+++ b/tools/clang/test/CodeGenHLSL/quick-test/subobjects.hlsl
@ -7,7 +7,8 @@
 // CHECK: ; SubobjectToExportsAssociation sea2 = { "grs", { }  };
 // CHECK: ; RaytracingShaderConfig rsc = { MaxPayloadSizeInBytes = 128, MaxAttributeSizeInBytes = 64 };
 // CHECK: ; RaytracingPipelineConfig rpc = { MaxTraceRecursionDepth = 512 };
-// CHECK: ; HitGroup hitGt = { anyhit = "a", closesthit = "b", intersection = "c" };
+// CHECK: ; HitGroup trHitGt = { HitGroupType = Triangle, Anyhit = "a", Closesthit = "b", Intersection = "" };
+// CHECK: ; HitGroup ppHitGt = { HitGroupType = ProceduralPrimitive, Anyhit = "a", Closesthit = "b", Intersection = "c" };

 GlobalRootSignature grs = {"CBV(b0)"};
 StateObjectConfig soc = { STATE_OBJECT_FLAGS_ALLOW_LOCAL_DEPENDENCIES_ON_EXTERNAL_DEFINITONS };
@ -16,7 +17,8 @@ SubobjectToExportsAssociation sea = { "grs", "a;b;foo;c" };
 SubobjectToExportsAssociation sea2 = { "grs", ";" };
 RaytracingShaderConfig rsc = { 128, 64 };
 RaytracingPipelineConfig rpc = { 512 };
-HitGroup hitGt = { "a", "b", "c"};
+TriangleHitGroup trHitGt = { "a", "b" };
+ProceduralPrimitiveHitGroup ppHitGt = { "a", "b", "c"};

 int main(int i : INDEX) : SV_Target {
  return 1;
--- a/tools/clang/test/HLSL/subobjects-syntax.hlsl
+++ b/tools/clang/test/HLSL/subobjects-syntax.hlsl
@ -66,24 +66,38 @@ RaytracingShaderConfig rsc2_7 = "foo";                      /* expected-error {{
 RaytracingShaderConfig rsc2_8 = 128;                        /* expected-error {{cannot initialize a variable of type 'RaytracingShaderConfig' with an rvalue of type 'literal int'}} */

 RaytracingPipelineConfig rpc1_1 = { 512 };
-RaytracingPipelineConfig rpc1_2 = { 512f };                 /* expected-error {{invalid digit 'f' in decimal constant}} */
+RaytracingPipelineConfig rpc1_2 = { 512.15f };                 /* expected-warning {{implicit conversion from 'float' to 'unsigned int' changes value from 512.15002 to 512}} */

 RaytracingPipelineConfig rpc2_2 = { 512, 128 };             /* expected-error {{too many elements in subobject initialization (expected 1 element, have 2)}} */
 RaytracingPipelineConfig rpc2_3 = 512;                      /* expected-error {{cannot initialize a variable of type 'RaytracingPipelineConfig' with an rvalue of type 'literal int'}} */
 RaytracingPipelineConfig rpc2_4 = 51.1f;                    /* expected-error {{cannot initialize a variable of type 'RaytracingPipelineConfig' with an rvalue of type 'float'}} */
 RaytracingPipelineConfig rpc2_5 = "foo";                    /* expected-error {{cannot initialize a variable of type 'RaytracingPipelineConfig' with an lvalue of type 'literal string'}} */

-HitGroup hitGt1_1 = { "a", "b", "c"};
-HitGroup hitGt1_2 = { s1, s2, s3 };
-HitGroup hitGt1_3 = { "", "", "" };
+TriangleHitGroup trHitGt1_1 = { "a", "b" };
+TriangleHitGroup trHitGt1_2 = { s1, s2 };
+TriangleHitGroup trHitGt1_3 = { "", "" };

-HitGroup hitGt2_2 = { "a", "b"};                            /* expected-error {{too few elements in subobject initialization (expected 3 elements, have 2)}} */
-HitGroup hitGt2_3 = { "a", "b", 10 };                       /* expected-error {{type mismatch}} */
-HitGroup hitGt2_4 = { 1, 2, 3 };                            /* expected-error {{type mismatch}} */
-HitGroup hitGt2_5 = "foo";                                  /* expected-error {{cannot initialize a variable of type 'HitGroup' with an lvalue of type 'literal string'}} */
-HitGroup hitGt2_6 = 115;                                    /* expected-error {{cannot initialize a variable of type 'HitGroup' with an rvalue of type 'literal int'}} */
-HitGroup hitGt2_7 = s2;                                     /* expected-error {{cannot initialize a variable of type 'HitGroup' with an lvalue of type 'string'}} */
-HitGroup hitGt2_8 = { s1, "", s4 };
+TriangleHitGroup trHitGt2_2 = { "a", "b", "c"};               /* expected-error {{too many elements in subobject initialization (expected 2 elements, have 3)}} */
+TriangleHitGroup trHitGt2_3 = { "a", 10 };                    /* expected-error {{type mismatch}} */
+TriangleHitGroup trHitGt2_4 = { 1, 2 };                       /* expected-error {{type mismatch}} */
+TriangleHitGroup trHitGt2_5 = "foo";                          /* expected-error {{cannot initialize a variable of type 'TriangleHitGroup' with an lvalue of type 'literal string'}} */
+TriangleHitGroup trHitGt2_6 = 115;                            /* expected-error {{cannot initialize a variable of type 'TriangleHitGroup' with an rvalue of type 'literal int'}} */
+TriangleHitGroup trHitGt2_7 = s2;                             /* expected-error {{cannot initialize a variable of type 'TriangleHitGroup' with an lvalue of type 'string'}} */
+
+ProceduralPrimitiveHitGroup ppHitGt1_1 = { "a", "b", "c"};
+ProceduralPrimitiveHitGroup ppHitGt1_2 = { s1, s2, s3 };
+ProceduralPrimitiveHitGroup ppHitGt1_3 = { "", "", "c" };
+
+ProceduralPrimitiveHitGroup ppHitGt2_2 = { "a", "b"};         /* expected-error {{too few elements in subobject initialization (expected 3 elements, have 2)}} */
+ProceduralPrimitiveHitGroup ppHitGt2_3 = { "a", "b", 10 };    /* expected-error {{type mismatch}} */
+ProceduralPrimitiveHitGroup ppHitGt2_4 = { 1, 2, 3 };         /* expected-error {{type mismatch}} */
+ProceduralPrimitiveHitGroup ppHitGt2_5 = "foo";               /* expected-error {{cannot initialize a variable of type 'ProceduralPrimitiveHitGroup' with an lvalue of type 'literal string'}} */
+ProceduralPrimitiveHitGroup ppHitGt2_6 = 115;                 /* expected-error {{cannot initialize a variable of type 'ProceduralPrimitiveHitGroup' with an rvalue of type 'literal int'}} */
+ProceduralPrimitiveHitGroup ppHitGt2_7 = s2;                  /* expected-error {{cannot initialize a variable of type 'ProceduralPrimitiveHitGroup' with an lvalue of type 'string'}} */
+
+TriangleHitGroup trHitGt2_8 = { s1, s4 };
+ProceduralPrimitiveHitGroup ppHitGt2_8 = { s1, "", s4 };
+ProceduralPrimitiveHitGroup ppHitGt2_9 = { "a", "b", ""};

 int main(int i : INDEX) : SV_Target {
  return 1;
--- a/tools/clang/tools/dxcompiler/dxcdisassembler.cpp
+++ b/tools/clang/tools/dxcompiler/dxcdisassembler.cpp
@ -601,6 +601,16 @@ static const char *FlagToString(DXIL::StateObjectFlags Flag) {
  return "<invalid StateObjectFlag>";
 }

+static const char *HitGroupTypeToString(DXIL::HitGroupType type) {
+  switch (type) {
+  case DXIL::HitGroupType::Triangle:
+    return "Triangle";
+  case DXIL::HitGroupType::ProceduralPrimitive:
+    return "ProceduralPrimitive";
+  }
+  return "<invalid HitGroupType>";
+}
+
 template <typename _T>
 void PrintFlags(raw_string_ostream &OS, uint32_t Flags) {
  if (!Flags) {
@ -702,16 +712,18 @@ void PrintSubobjects(const DxilSubobjects &subobjects,
      break;
    }
    case DXIL::SubobjectKind::HitGroup: {
+      HitGroupType hgType;
      StringRef AnyHit;
      StringRef ClosestHit;
      StringRef Intersection;
-      if (!obj.GetHitGroup(AnyHit, ClosestHit, Intersection)) {
+      if (!obj.GetHitGroup(hgType, AnyHit, ClosestHit, Intersection)) {
        OS << "<error getting subobject>";
        break;
      }
-      OS << "anyhit = \"" << AnyHit
-         << "\", closesthit = \"" << ClosestHit
-         << "\", intersection = \"" << Intersection << "\"";
+      OS << "HitGroupType = " << HitGroupTypeToString(hgType) 
+         << ", Anyhit = \"" << AnyHit
+         << "\", Closesthit = \"" << ClosestHit
+         << "\", Intersection = \"" << Intersection << "\"";
      break;
    }
    }
--- a/tools/clang/unittests/HLSL/CompilerTest.cpp
+++ b/tools/clang/unittests/HLSL/CompilerTest.cpp
@ -5954,13 +5954,17 @@ TEST_F(CompilerTest, SubobjectCodeGenErrors) {
    { "SubobjectToExportsAssociation sea;", "1:1: error: subobject needs to be initialized" },
    { "RaytracingShaderConfig rsc;",        "1:1: error: subobject needs to be initialized" },
    { "RaytracingPipelineConfig rpc;",      "1:1: error: subobject needs to be initialized" },
-    { "HitGroup hitGt;",                    "1:1: error: subobject needs to be initialized" },
+    { "TriangleHitGroup hitGt;",            "1:1: error: subobject needs to be initialized" },
+    { "ProceduralPrimitiveHitGroup hitGt;", "1:1: error: subobject needs to be initialized" },
    { "GlobalRootSignature grs2 = {\"\"};", "1:29: error: empty string not expected here" },
    { "LocalRootSignature lrs2 = {\"\"};",  "1:28: error: empty string not expected here" },
    { "SubobjectToExportsAssociation sea2 = { \"\", \"x\" };", "1:40: error: empty string not expected here" },
    { "SubobjectToExportsAssociation sea3 = { \"x\", \"\" };", "1:45: error: empty string not expected here" },
    { "string s; SubobjectToExportsAssociation sea4 = { \"x\", s };", "1:55: error: cannot convert to constant string" },
-    { "extern int v; RaytracingPipelineConfig rpc2 = { v + 16 };", "1:49: error: cannot convert to constant unsigned int" }
+    { "extern int v; RaytracingPipelineConfig rpc2 = { v + 16 };", "1:49: error: cannot convert to constant unsigned int" },
+    { "string s; TriangleHitGroup trHitGt2_8 = { s, \"foo\" };", "1:43: error: cannot convert to constant string" },
+    { "string s; ProceduralPrimitiveHitGroup ppHitGt2_8 = { s, \"\", s };", "1:54: error: cannot convert to constant string" },
+    { "ProceduralPrimitiveHitGroup ppHitGt2_9 = { \"a\", \"b\", \"\"};", "1:54: error: empty string not expected here" }
  };

  for (unsigned i = 0; i < _countof(testCases); i++) {