[DirectX] Add DXIL metadata `dx.shaderModel`

This captures the target shader model and pipeline stage into the DXIL
metadata for consumption by the DirectX runtime.

Reviewed By: python3kgae

Differential Revision: https://reviews.llvm.org/D134469

llvm/lib/Target/DirectX/DXILMetadata.cpp

@@ -11,6 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "DXILMetadata.h"
+#include "llvm/ADT/Triple.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/Module.h"
@@ -38,3 +39,44 @@ void ValidatorVersionMD::update(VersionTuple ValidatorVer) {
 }
 
 bool ValidatorVersionMD::isEmpty() { return Entry->getNumOperands() == 0; }
+
+static StringRef getShortShaderStage(Triple::EnvironmentType Env) {
+  switch (Env) {
+  case Triple::Pixel:
+    return "ps";
+  case Triple::Vertex:
+    return "vs";
+  case Triple::Geometry:
+    return "gs";
+  case Triple::Hull:
+    return "hs";
+  case Triple::Domain:
+    return "ds";
+  case Triple::Compute:
+    return "cs";
+  case Triple::Library:
+    return "lib";
+  case Triple::Mesh:
+    return "ms";
+  case Triple::Amplification:
+    return "as";
+  default:
+    break;
+  }
+  llvm_unreachable("Unsupported environment for DXIL generation.");
+  return "";
+}
+
+void dxil::createShaderModelMD(Module &M) {
+  NamedMDNode *Entry = M.getOrInsertNamedMetadata("dx.shaderModel");
+  Triple TT(M.getTargetTriple());
+  VersionTuple Ver = TT.getOSVersion();
+  LLVMContext &Ctx = M.getContext();
+  IRBuilder<> B(Ctx);
+
+  Metadata *Vals[3];
+  Vals[0] = MDString::get(Ctx, getShortShaderStage(TT.getEnvironment()));
+  Vals[1] = ConstantAsMetadata::get(B.getInt32(Ver.getMajor()));
+  Vals[2] = ConstantAsMetadata::get(B.getInt32(Ver.getMinor().value_or(0)));
+  Entry->addOperand(MDNode::get(Ctx, Vals));
+}

llvm/lib/Target/DirectX/DXILMetadata.h

@@ -30,6 +30,8 @@ public:
   bool isEmpty();
 };
 
+void createShaderModelMD(Module &M);
+
 } // namespace dxil
 } // namespace llvm
 

llvm/lib/Target/DirectX/DXILTranslateMetadata.cpp

@@ -37,6 +37,7 @@ bool DXILTranslateMetadata::runOnModule(Module &M) {
   dxil::ValidatorVersionMD ValVerMD(M);
   if (ValVerMD.isEmpty())
     ValVerMD.update(VersionTuple(1, 0));
+  dxil::createShaderModelMD(M);
   return false;
 }
 

llvm/test/CodeGen/DirectX/Metadata/shaderModel-as.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6-amplification"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"as", i32 6, i32 0}

llvm/test/CodeGen/DirectX/Metadata/shaderModel-cs.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"cs", i32 6, i32 6}

llvm/test/CodeGen/DirectX/Metadata/shaderModel-gs.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6.6-geometry"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"gs", i32 6, i32 6}

llvm/test/CodeGen/DirectX/Metadata/shaderModel-hs.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6.6-hull"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"hs", i32 6, i32 6}

llvm/test/CodeGen/DirectX/Metadata/shaderModel-lib.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6.3-library"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"lib", i32 6, i32 3}

llvm/test/CodeGen/DirectX/Metadata/shaderModel-ms.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel6.6-mesh"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"ms", i32 6, i32 6}

llvm/test/CodeGen/DirectX/Metadata/shaderModel-ps.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel5.0-pixel"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"ps", i32 5, i32 0}

llvm/test/CodeGen/DirectX/Metadata/shaderModel-vs.ll

@@ -0,0 +1,5 @@
+; RUN: opt -S -dxil-metadata-emit %s | FileCheck %s
+target triple = "dxil-pc-shadermodel-vertex"
+
+; CHECK: !dx.shaderModel = !{![[SM:[0-9]+]]}
+; CHECK: ![[SM]] = !{!"vs", i32 0, i32 0}