[Mlir-commits] [mlir] [MLIR][NVVM] Add support for narrow-fp to bf16x2 conversions (PR #200157)

[Durgadoss R]

================
@@ -4877,6 +4930,41 @@ NVVM::IDArgPair ConvertF4x2ToF16x2Op::getIntrinsicIDAndArgs(
   return {intId, {extendedI16}};
 }
 
+NVVM::IDArgPair ConvertF4x2ToBF16x2Op::getIntrinsicIDAndArgs(
+    Operation &op, LLVM::ModuleTranslation &mt, llvm::IRBuilderBase &builder) {
+  auto curOp = cast<NVVM::ConvertF4x2ToBF16x2Op>(op);
+  bool hasScale = static_cast<bool>(curOp.getScaleFactor());
+  bool hasSatfinite = curOp.getSat() == NVVM::SaturationMode::SATFINITE;
+  bool hasRelu = curOp.getRelu();
+
+  static constexpr llvm::Intrinsic::ID E2M1Ids[] = {
+      llvm::Intrinsic::nvvm_e2m1x2_to_bf16x2_rn_scale_n2_ue8m0,
+      llvm::Intrinsic::nvvm_e2m1x2_to_bf16x2_rn_relu_scale_n2_ue8m0,
+      llvm::Intrinsic::nvvm_e2m1x2_to_bf16x2_rn_satfinite_scale_n2_ue8m0,
+      llvm::Intrinsic::nvvm_e2m1x2_to_bf16x2_rn_relu_satfinite_scale_n2_ue8m0,
+  };
+
+  unsigned idx = (hasSatfinite << 1) | hasRelu;
+  llvm::Intrinsic::ID intId =
+      llvm::TypeSwitch<mlir::Type, llvm::Intrinsic::ID>(curOp.getSrcType())
+          .Case([&](Float4E2M1FNType type) { return E2M1Ids[idx]; })
+          .Default([](mlir::Type type) {
+            llvm_unreachable("Invalid type for ConvertF4x2ToBF16x2Op");
+            return llvm::Intrinsic::not_intrinsic;
+          });
+
+  llvm::Value *extendedI16 =
+      builder.CreateZExt(mt.lookupValue(curOp.getSrc()),
+                         llvm::Type::getInt16Ty(builder.getContext()));
+
+  llvm::SmallVector<llvm::Value *> args;
+  args.push_back(extendedI16);
+  args.push_back(hasScale ? mt.lookupValue(curOp.getScaleFactor())
+                          : builder.getInt16(0x7f7f));
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durga4github wrote:

Can we add a one liner comment here about this being the default-sf value?

https://github.com/llvm/llvm-project/pull/200157