[flang] Use default constructor for FIRToSCF pass (#169741)

Author: clementval

flang/include/flang/Optimizer/Transforms/Passes.h

@@ -40,7 +40,6 @@ std::unique_ptr<mlir::Pass>
 createArrayValueCopyPass(fir::ArrayValueCopyOptions options = {});
 std::unique_ptr<mlir::Pass> createMemDataFlowOptPass();
 std::unique_ptr<mlir::Pass> createPromoteToAffinePass();
-std::unique_ptr<mlir::Pass> createFIRToSCFPass();
 std::unique_ptr<mlir::Pass>
 createAddDebugInfoPass(fir::AddDebugInfoOptions options = {});
 

flang/include/flang/Optimizer/Transforms/Passes.td

@@ -81,7 +81,6 @@ def FIRToSCFPass : Pass<"fir-to-scf"> {
   let description = [{
     Convert FIR structured control flow ops to SCF dialect.
   }];
-  let constructor = "::fir::createFIRToSCFPass()";
   let dependentDialects = [
     "fir::FIROpsDialect", "mlir::scf::SCFDialect"
   ];

flang/lib/Optimizer/Transforms/FIRToSCF.cpp

@@ -18,6 +18,8 @@ namespace fir {
 
 namespace {
 class FIRToSCFPass : public fir::impl::FIRToSCFPassBase<FIRToSCFPass> {
+  using FIRToSCFPassBase::FIRToSCFPassBase;
+
 public:
   void runOnOperation() override;
 };
@@ -230,7 +232,3 @@ void FIRToSCFPass::runOnOperation() {
   fir::populateFIRToSCFRewrites(patterns, parallelUnordered);
   walkAndApplyPatterns(getOperation(), std::move(patterns));
 }
-
-std::unique_ptr<mlir::Pass> fir::createFIRToSCFPass() {
-  return std::make_unique<FIRToSCFPass>();
-}