[ValueTypes][NFC] Generate EVT::getTypeForEVT from GenVT.inc (#96608)

Most of MVT has simple mapping to the LLVM type, so it would be nice to
auto generate that from ValueTypes.td, that could reduce the effort when
we adding new MVT, especially new vector MVT with different size.

2 files changed, 67 insertions, 361 deletions

diff --git a/llvm/lib/CodeGen/ValueTypes.cpp b/llvm/lib/CodeGen/ValueTypes.cpp
index df1c02c..b0f736a 100644
--- a/llvm/lib/CodeGen/ValueTypes.cpp
+++ b/llvm/lib/CodeGen/ValueTypes.cpp
@@ -207,21 +207,6 @@ Type *EVT::getTypeForEVT(LLVMContext &Context) const {
     assert(isExtended() && "Type is not extended!");
     return LLVMTy;
   case MVT::isVoid:  return Type::getVoidTy(Context);
-  case MVT::i1:      return Type::getInt1Ty(Context);
-  case MVT::i2:      return Type::getIntNTy(Context, 2);
-  case MVT::i4:      return Type::getIntNTy(Context, 4);
-  case MVT::i8:      return Type::getInt8Ty(Context);
-  case MVT::i16:     return Type::getInt16Ty(Context);
-  case MVT::i32:     return Type::getInt32Ty(Context);
-  case MVT::i64:     return Type::getInt64Ty(Context);
-  case MVT::i128:    return IntegerType::get(Context, 128);
-  case MVT::f16:     return Type::getHalfTy(Context);
-  case MVT::bf16:    return Type::getBFloatTy(Context);
-  case MVT::f32:     return Type::getFloatTy(Context);
-  case MVT::f64:     return Type::getDoubleTy(Context);
-  case MVT::f80:     return Type::getX86_FP80Ty(Context);
-  case MVT::f128:    return Type::getFP128Ty(Context);
-  case MVT::ppcf128: return Type::getPPC_FP128Ty(Context);
   case MVT::x86mmx:  return Type::getX86_MMXTy(Context);
   case MVT::aarch64svcount:
     return TargetExtType::get(Context, "aarch64.svcount");
@@ -229,353 +214,10 @@ Type *EVT::getTypeForEVT(LLVMContext &Context) const {
   case MVT::i64x8:   return IntegerType::get(Context, 512);
   case MVT::externref: return Type::getWasm_ExternrefTy(Context);
   case MVT::funcref: return Type::getWasm_FuncrefTy(Context);
-  case MVT::v1i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 1);
-  case MVT::v2i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 2);
-  case MVT::v3i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 3);
-  case MVT::v4i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 4);
-  case MVT::v8i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 8);
-  case MVT::v16i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 16);
-  case MVT::v32i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 32);
-  case MVT::v64i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 64);
-  case MVT::v128i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 128);
-  case MVT::v256i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 256);
-  case MVT::v512i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 512);
-  case MVT::v1024i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 1024);
-  case MVT::v2048i1:
-    return FixedVectorType::get(Type::getInt1Ty(Context), 2048);
-  case MVT::v128i2:
-    return FixedVectorType::get(Type::getIntNTy(Context, 2), 128);
-  case MVT::v256i2:
-    return FixedVectorType::get(Type::getIntNTy(Context, 2), 256);
-  case MVT::v64i4:
-    return FixedVectorType::get(Type::getIntNTy(Context, 4), 64);
-  case MVT::v128i4:
-    return FixedVectorType::get(Type::getIntNTy(Context, 4), 128);
-  case MVT::v1i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 1);
-  case MVT::v2i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 2);
-  case MVT::v3i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 3);
-  case MVT::v4i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 4);
-  case MVT::v8i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 8);
-  case MVT::v16i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 16);
-  case MVT::v32i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 32);
-  case MVT::v64i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 64);
-  case MVT::v128i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 128);
-  case MVT::v256i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 256);
-  case MVT::v512i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 512);
-  case MVT::v1024i8:
-    return FixedVectorType::get(Type::getInt8Ty(Context), 1024);
-  case MVT::v1i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 1);
-  case MVT::v2i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 2);
-  case MVT::v3i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 3);
-  case MVT::v4i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 4);
-  case MVT::v8i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 8);
-  case MVT::v16i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 16);
-  case MVT::v32i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 32);
-  case MVT::v64i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 64);
-  case MVT::v128i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 128);
-  case MVT::v256i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 256);
-  case MVT::v512i16:
-    return FixedVectorType::get(Type::getInt16Ty(Context), 512);
-  case MVT::v1i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 1);
-  case MVT::v2i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 2);
-  case MVT::v3i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 3);
-  case MVT::v4i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 4);
-  case MVT::v5i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 5);
-  case MVT::v6i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 6);
-  case MVT::v7i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 7);
-  case MVT::v8i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 8);
-  case MVT::v9i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 9);
-  case MVT::v10i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 10);
-  case MVT::v11i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 11);
-  case MVT::v12i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 12);
-  case MVT::v16i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 16);
-  case MVT::v32i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 32);
-  case MVT::v64i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 64);
-  case MVT::v128i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 128);
-  case MVT::v256i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 256);
-  case MVT::v512i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 512);
-  case MVT::v1024i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 1024);
-  case MVT::v2048i32:
-    return FixedVectorType::get(Type::getInt32Ty(Context), 2048);
-  case MVT::v1i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 1);
-  case MVT::v2i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 2);
-  case MVT::v3i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 3);
-  case MVT::v4i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 4);
-  case MVT::v8i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 8);
-  case MVT::v16i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 16);
-  case MVT::v32i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 32);
-  case MVT::v64i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 64);
-  case MVT::v128i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 128);
-  case MVT::v256i64:
-    return FixedVectorType::get(Type::getInt64Ty(Context), 256);
-  case MVT::v1i128:
-    return FixedVectorType::get(Type::getInt128Ty(Context), 1);
-  case MVT::v1f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 1);
-  case MVT::v2f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 2);
-  case MVT::v3f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 3);
-  case MVT::v4f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 4);
-  case MVT::v8f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 8);
-  case MVT::v16f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 16);
-  case MVT::v32f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 32);
-  case MVT::v64f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 64);
-  case MVT::v128f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 128);
-  case MVT::v256f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 256);
-  case MVT::v512f16:
-    return FixedVectorType::get(Type::getHalfTy(Context), 512);
-  case MVT::v2bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 2);
-  case MVT::v3bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 3);
-  case MVT::v4bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 4);
-  case MVT::v8bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 8);
-  case MVT::v16bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 16);
-  case MVT::v32bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 32);
-  case MVT::v64bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 64);
-  case MVT::v128bf16:
-    return FixedVectorType::get(Type::getBFloatTy(Context), 128);
-  case MVT::v1f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 1);
-  case MVT::v2f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 2);
-  case MVT::v3f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 3);
-  case MVT::v4f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 4);
-  case MVT::v5f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 5);
-  case MVT::v6f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 6);
-  case MVT::v7f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 7);
-  case MVT::v8f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 8);
-  case MVT::v9f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 9);
-  case MVT::v10f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 10);
-  case MVT::v11f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 11);
-  case MVT::v12f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 12);
-  case MVT::v16f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 16);
-  case MVT::v32f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 32);
-  case MVT::v64f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 64);
-  case MVT::v128f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 128);
-  case MVT::v256f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 256);
-  case MVT::v512f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 512);
-  case MVT::v1024f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 1024);
-  case MVT::v2048f32:
-    return FixedVectorType::get(Type::getFloatTy(Context), 2048);
-  case MVT::v1f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 1);
-  case MVT::v2f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 2);
-  case MVT::v3f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 3);
-  case MVT::v4f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 4);
-  case MVT::v8f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 8);
-  case MVT::v16f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 16);
-  case MVT::v32f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 32);
-  case MVT::v64f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 64);
-  case MVT::v128f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 128);
-  case MVT::v256f64:
-    return FixedVectorType::get(Type::getDoubleTy(Context), 256);
-  case MVT::nxv1i1:
-    return ScalableVectorType::get(Type::getInt1Ty(Context), 1);
-  case MVT::nxv2i1:
-    return ScalableVectorType::get(Type::getInt1Ty(Context), 2);
-  case MVT::nxv4i1:
-    return ScalableVectorType::get(Type::getInt1Ty(Context), 4);
-  case MVT::nxv8i1:
-    return ScalableVectorType::get(Type::getInt1Ty(Context), 8);
-  case MVT::nxv16i1:
-    return ScalableVectorType::get(Type::getInt1Ty(Context), 16);
-  case MVT::nxv32i1:
-    return ScalableVectorType::get(Type::getInt1Ty(Context), 32);
-  case MVT::nxv64i1:
-    return ScalableVectorType::get(Type::getInt1Ty(Context), 64);
-  case MVT::nxv1i8:
-    return ScalableVectorType::get(Type::getInt8Ty(Context), 1);
-  case MVT::nxv2i8:
-    return ScalableVectorType::get(Type::getInt8Ty(Context), 2);
-  case MVT::nxv4i8:
-    return ScalableVectorType::get(Type::getInt8Ty(Context), 4);
-  case MVT::nxv8i8:
-    return ScalableVectorType::get(Type::getInt8Ty(Context), 8);
-  case MVT::nxv16i8:
-    return ScalableVectorType::get(Type::getInt8Ty(Context), 16);
-  case MVT::nxv32i8:
-    return ScalableVectorType::get(Type::getInt8Ty(Context), 32);
-  case MVT::nxv64i8:
-    return ScalableVectorType::get(Type::getInt8Ty(Context), 64);
-  case MVT::nxv1i16:
-    return ScalableVectorType::get(Type::getInt16Ty(Context), 1);
-  case MVT::nxv2i16:
-    return ScalableVectorType::get(Type::getInt16Ty(Context), 2);
-  case MVT::nxv4i16:
-    return ScalableVectorType::get(Type::getInt16Ty(Context), 4);
-  case MVT::nxv8i16:
-    return ScalableVectorType::get(Type::getInt16Ty(Context), 8);
-  case MVT::nxv16i16:
-    return ScalableVectorType::get(Type::getInt16Ty(Context), 16);
-  case MVT::nxv32i16:
-    return ScalableVectorType::get(Type::getInt16Ty(Context), 32);
-  case MVT::nxv1i32:
-    return ScalableVectorType::get(Type::getInt32Ty(Context), 1);
-  case MVT::nxv2i32:
-    return ScalableVectorType::get(Type::getInt32Ty(Context), 2);
-  case MVT::nxv4i32:
-    return ScalableVectorType::get(Type::getInt32Ty(Context), 4);
-  case MVT::nxv8i32:
-    return ScalableVectorType::get(Type::getInt32Ty(Context), 8);
-  case MVT::nxv16i32:
-    return ScalableVectorType::get(Type::getInt32Ty(Context), 16);
-  case MVT::nxv32i32:
-    return ScalableVectorType::get(Type::getInt32Ty(Context), 32);
-  case MVT::nxv1i64:
-    return ScalableVectorType::get(Type::getInt64Ty(Context), 1);
-  case MVT::nxv2i64:
-    return ScalableVectorType::get(Type::getInt64Ty(Context), 2);
-  case MVT::nxv4i64:
-    return ScalableVectorType::get(Type::getInt64Ty(Context), 4);
-  case MVT::nxv8i64:
-    return ScalableVectorType::get(Type::getInt64Ty(Context), 8);
-  case MVT::nxv16i64:
-    return ScalableVectorType::get(Type::getInt64Ty(Context), 16);
-  case MVT::nxv32i64:
-    return ScalableVectorType::get(Type::getInt64Ty(Context), 32);
-  case MVT::nxv1f16:
-    return ScalableVectorType::get(Type::getHalfTy(Context), 1);
-  case MVT::nxv2f16:
-    return ScalableVectorType::get(Type::getHalfTy(Context), 2);
-  case MVT::nxv4f16:
-    return ScalableVectorType::get(Type::getHalfTy(Context), 4);
-  case MVT::nxv8f16:
-    return ScalableVectorType::get(Type::getHalfTy(Context), 8);
-  case MVT::nxv16f16:
-    return ScalableVectorType::get(Type::getHalfTy(Context), 16);
-  case MVT::nxv32f16:
-    return ScalableVectorType::get(Type::getHalfTy(Context), 32);
-  case MVT::nxv1bf16:
-    return ScalableVectorType::get(Type::getBFloatTy(Context), 1);
-  case MVT::nxv2bf16:
-    return ScalableVectorType::get(Type::getBFloatTy(Context), 2);
-  case MVT::nxv4bf16:
-    return ScalableVectorType::get(Type::getBFloatTy(Context), 4);
-  case MVT::nxv8bf16:
-    return ScalableVectorType::get(Type::getBFloatTy(Context), 8);
-  case MVT::nxv16bf16:
-    return ScalableVectorType::get(Type::getBFloatTy(Context), 16);
-  case MVT::nxv32bf16:
-    return ScalableVectorType::get(Type::getBFloatTy(Context), 32);
-  case MVT::nxv1f32:
-    return ScalableVectorType::get(Type::getFloatTy(Context), 1);
-  case MVT::nxv2f32:
-    return ScalableVectorType::get(Type::getFloatTy(Context), 2);
-  case MVT::nxv4f32:
-    return ScalableVectorType::get(Type::getFloatTy(Context), 4);
-  case MVT::nxv8f32:
-    return ScalableVectorType::get(Type::getFloatTy(Context), 8);
-  case MVT::nxv16f32:
-    return ScalableVectorType::get(Type::getFloatTy(Context), 16);
-  case MVT::nxv1f64:
-    return ScalableVectorType::get(Type::getDoubleTy(Context), 1);
-  case MVT::nxv2f64:
-    return ScalableVectorType::get(Type::getDoubleTy(Context), 2);
-  case MVT::nxv4f64:
-    return ScalableVectorType::get(Type::getDoubleTy(Context), 4);
-  case MVT::nxv8f64:
-    return ScalableVectorType::get(Type::getDoubleTy(Context), 8);
   case MVT::Metadata: return Type::getMetadataTy(Context);
+#define GET_VT_EVT(Ty, EVT) case MVT::Ty: return EVT;
+#include "llvm/CodeGen/GenVT.inc"
+#undef GET_VT_EVT
   }
   // clang-format on
 }
diff --git a/llvm/utils/TableGen/VTEmitter.cpp b/llvm/utils/TableGen/VTEmitter.cpp
index 3187548..851a525 100644
--- a/llvm/utils/TableGen/VTEmitter.cpp
+++ b/llvm/utils/TableGen/VTEmitter.cpp
@@ -29,6 +29,53 @@ public:
 
 } // End anonymous namespace.
 
+static void VTtoGetLLVMTyString(raw_ostream &OS, const Record *VT) {
+  bool IsVector = VT->getValueAsBit("isVector");
+  if (IsVector)
+    OS << (VT->getValueAsBit("isScalable") ? "Scalable" : "Fixed")
+       << "VectorType::get(";
+
+  auto OutputVT = IsVector ? VT->getValueAsDef("ElementType") : VT;
+  int64_t OutputVTSize = OutputVT->getValueAsInt("Size");
+
+  if (OutputVT->getValueAsBit("isFP")) {
+    StringRef FloatTy;
+    auto OutputVTName = OutputVT->getValueAsString("LLVMName");
+    switch (OutputVTSize) {
+    default:
+      llvm_unreachable("Unhandled case");
+    case 16:
+      FloatTy = (OutputVTName == "bf16") ? "BFloatTy" : "HalfTy";
+      break;
+    case 32:
+      FloatTy = "FloatTy";
+      break;
+    case 64:
+      FloatTy = "DoubleTy";
+      break;
+    case 80:
+      FloatTy = "X86_FP80Ty";
+      break;
+    case 128:
+      FloatTy = (OutputVTName == "ppcf128") ? "PPC_FP128Ty" : "FP128Ty";
+      break;
+    }
+    OS << "Type::get" << FloatTy << "(Context)";
+  } else if (OutputVT->getValueAsBit("isInteger")) {
+    // We only have Type::getInt1Ty, Int8, Int16, Int32, Int64, and Int128
+    if ((isPowerOf2_64(OutputVTSize) && OutputVTSize >= 8 &&
+         OutputVTSize <= 128) ||
+        OutputVTSize == 1)
+      OS << "Type::getInt" << OutputVTSize << "Ty(Context)";
+    else
+      OS << "Type::getIntNTy(Context, " << OutputVTSize << ")";
+  } else
+    llvm_unreachable("Unhandled case");
+
+  if (IsVector)
+    OS << ", " << VT->getValueAsInt("nElem") << ")";
+}
+
 void VTEmitter::run(raw_ostream &OS) {
   emitSourceFileHeader("ValueTypes Source Fragment", OS, Records);
 
@@ -130,6 +177,23 @@ void VTEmitter::run(raw_ostream &OS) {
     // clang-format on
   }
   OS << "#endif\n\n";
+
+  OS << "#ifdef GET_VT_EVT\n";
+  for (const auto *VT : VTsByNumber) {
+    if (!VT)
+      continue;
+    bool IsInteger = VT->getValueAsBit("isInteger");
+    bool IsVector = VT->getValueAsBit("isVector");
+    bool IsFP = VT->getValueAsBit("isFP");
+
+    if (!IsInteger && !IsVector && !IsFP)
+      continue;
+
+    OS << "  GET_VT_EVT(" << VT->getValueAsString("LLVMName") << ", ";
+    VTtoGetLLVMTyString(OS, VT);
+    OS << ")\n";
+  }
+  OS << "#endif\n\n";
 }
 
 static TableGen::Emitter::OptClass<VTEmitter> X("gen-vt", "Generate ValueType");