[SPIRV] Allow spirv type as template parameter (microsoft#7626)

SPIR-V intrinsics allow us to create spirv basic type and opaque type in
HLSL, but these type are object and not allowed in template parameter.

```fundamental
error: object 'Int8Type' is not allowed in builtin template parameters
    /* OpTypeCooperativeMatrixKHR */ 4456, Int8Type,
                                           ^
```

This doesn't make sense to me, and is not convenience to use. This
change wants to allow that use those in template parameter.

Author: GinShio

tools/clang/lib/Sema/SemaHLSL.cpp

@@ -5402,6 +5402,15 @@ class HLSLExternalSource : public ExternalSemaSource {
         objectKind = ClassifyRecordType(recordType);
         switch (objectKind) {
         case AR_TOBJ_OBJECT:
+#ifdef ENABLE_SPIRV_CODEGEN
+          if (const auto *namespaceDecl = dyn_cast<NamespaceDecl>(
+                  recordType->getDecl()->getDeclContext());
+              namespaceDecl && namespaceDecl->getName().equals("vk") &&
+              (recordType->getDecl()->getName().equals("SpirvType") ||
+               recordType->getDecl()->getName().equals("SpirvOpaqueType"))) {
+            return true;
+          }
+#endif
           m_sema->Diag(argLoc, diag::err_hlsl_unsupported_object_context)
               << type << static_cast<unsigned>(TypeDiagContext::TypeParameter);
           return false;

tools/clang/test/CodeGenSPIRV/spv.intrinsicInTemplate.hlsl

@@ -0,0 +1,29 @@
+// RUN: %dxc -T cs_6_8 -HV 2021 -O0 -spirv -fspv-target-env=universal1.5 %s | FileCheck %s
+
+// CHECK: [[Int8Type:%.*]] = OpTypeInt 8 0
+using Int8Type = vk::SpirvType</* OpTypeInt */ 21, 8, 8,
+                               vk::Literal<vk::integral_constant<uint32_t, 8> >,
+                               vk::Literal<vk::integral_constant<bool, 0> > >;
+
+// CHECK: [[MatrixType:%.*]] = OpTypeCooperativeMatrixKHR [[Int8Type]] %uint_3 %uint_16 %uint_16 %uint_0
+using I8MatA = vk::SpirvOpaqueType<
+    /* OpTypeCooperativeMatrixKHR */ 4456, Int8Type,
+    vk::integral_constant<uint, /* ScopeSubgroup */ 3>,
+    vk::integral_constant<uint, 16>, vk::integral_constant<uint, 16>,
+    vk::integral_constant<uint, /* Use */ 0> >;
+
+template <typename ResultType, typename PointerType>
+[[vk::ext_instruction(/* OpCooperativeMatrixLoadKHR */ 4457)]] ResultType
+__builtin_spv_CooperativeMatrixLoadKHR([[vk::ext_reference]] PointerType pointer,
+    uint32_t memory_layout, uint32_t stride, [[vk::ext_literal]] uint32_t memory_operand);
+
+StructuredBuffer<uint32_t> buffer : register(t0, space0);
+
+[numthreads(32, 1, 1)] void main() {
+  [[vk::ext_extension("SPV_KHR_cooperative_matrix")]]
+  [[vk::ext_capability(/* CooperativeMatrixKHRCapability */ 6022)]]
+  [[vk::ext_capability(/* VulkanMemoryModel */ 5345)]]
+  [[vk::ext_capability(/* Int8 */ 39)]]
+  // CHECK: OpCooperativeMatrixLoadKHR [[MatrixType]] %{{.*}} %uint_0 %uint_32 None
+  I8MatA matA = __builtin_spv_CooperativeMatrixLoadKHR<I8MatA>(buffer[0], /* rowMajor */ 0, 32, 0);
+}