[DirectX backend] emit metadata for DXIL version.

Emit named metadata "dx.version".

Default to DXIL 1.0

Author: python3kgae

llvm/lib/Target/DirectX/DXILMetadata.cpp

@@ -81,6 +81,18 @@ void dxil::createShaderModelMD(Module &M) {
   Entry->addOperand(MDNode::get(Ctx, Vals));
 }
 
+void dxil::createDXILVersionMD(Module &M) {
+  Triple TT(M.getTargetTriple());
+  VersionTuple Ver = TT.getOSVersion();
+  LLVMContext &Ctx = M.getContext();
+  IRBuilder<> B(Ctx);
+  NamedMDNode *Entry = M.getOrInsertNamedMetadata("dx.version");
+  Metadata *Vals[2];
+  Vals[0] = ConstantAsMetadata::get(B.getInt32(1));
+  Vals[1] = ConstantAsMetadata::get(B.getInt32(Ver.getMinor().value_or(0)));
+  Entry->addOperand(MDNode::get(Ctx, Vals));
+}
+
 static uint32_t getShaderStage(Triple::EnvironmentType Env) {
   return (uint32_t)Env - (uint32_t)llvm::Triple::Pixel;
 }

llvm/lib/Target/DirectX/DXILMetadata.h

@@ -33,6 +33,7 @@ class ValidatorVersionMD {
 };
 
 void createShaderModelMD(Module &M);
+void createDXILVersionMD(Module &M);
 void createEntryMD(Module &M, const uint64_t ShaderFlags);
 
 } // namespace dxil

llvm/lib/Target/DirectX/DXILTranslateMetadata.cpp

@@ -48,6 +48,7 @@ bool DXILTranslateMetadata::runOnModule(Module &M) {
   if (ValVerMD.isEmpty())
     ValVerMD.update(VersionTuple(1, 0));
   dxil::createShaderModelMD(M);
+  dxil::createDXILVersionMD(M);
 
   const dxil::Resources &Res =
       getAnalysis<DXILResourceWrapper>().getDXILResource();

llvm/test/CodeGen/DirectX/Metadata/dxilVer-1.0.ll

@@ -0,0 +1,12 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6.0-vertex"
+
+; CHECK: !dx.version = !{![[DXVER:[0-9]+]]}
+; CHECK: ![[DXVER]] = !{i32 1, i32 0}
+
+define void @entry() #0 {
+entry:
+  ret void
+}
+
+attributes #0 = { noinline nounwind "hlsl.shader"="vertex" }

llvm/test/CodeGen/DirectX/Metadata/dxilVer-1.8.ll

@@ -0,0 +1,12 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6.8-compute"
+
+; CHECK: !dx.version = !{![[DXVER:[0-9]+]]}
+; CHECK: ![[DXVER]] = !{i32 1, i32 8}
+
+define void @entry() #0 {
+entry:
+  ret void
+}
+
+attributes #0 = { noinline nounwind "hlsl.numthreads"="1,2,1" "hlsl.shader"="compute" }