FuncToEmitC: fix crash when there are no results

Author: mgehre-amd

mlir/lib/Conversion/FuncToEmitC/FuncToEmitC.cpp

@@ -37,16 +37,13 @@ class CallOpConversion final : public OpConversionPattern<func::CallOp> {
           callOp, "only functions with zero or one result can be converted");
 
     // Convert the original function results.
-    Type resultTy = nullptr;
-    if (callOp.getNumResults()) {
-      resultTy = typeConverter->convertType(callOp.getResult(0).getType());
-      if (!resultTy)
-        return rewriter.notifyMatchFailure(
-            callOp, "function return type conversion failed");
+    SmallVector<Type> types;
+    if (failed(typeConverter->convertTypes(callOp.getResultTypes(), types))) {
+      return rewriter.notifyMatchFailure(
+          callOp, "function return type conversion failed");
     }
-
     rewriter.replaceOpWithNewOp<emitc::CallOp>(
-        callOp, resultTy, adaptor.getOperands(), callOp->getAttrs());
+        callOp, types, adaptor.getOperands(), callOp->getAttrs());
 
     return success();
   }