[flang][CodeGen][NFC] Reduce boilerplatre for ExternalNameConversion

[tblah]

Use tablegen to generate the pass constructor.

I removed the duplicated pass option handling. I don't understand why the manual instantiation of the pass needs its own duplicate of the pass options in the (automatically generated) base class (even with the option to ignore the pass options in the base class).

This pass doesn't need changes to support other top level operations.

[llvmbot]

@llvm/pr-subscribers-flang-fir-hlfir

Author: Tom Eccles (tblah)

Changes

Use tablegen to generate the pass constructor.

I removed the duplicated pass option handling. I don't understand why the manual instantiation of the pass needs its own duplicate of the pass options in the (automatically generated) base class (even with the option to ignore the pass options in the base class).

This pass doesn't need changes to support other top level operations.

---

Full diff: https://github.com/llvm/llvm-project/pull/94474.diff

4 Files Affected:

• (modified) flang/include/flang/Optimizer/Transforms/Passes.h (-3)
• (modified) flang/include/flang/Optimizer/Transforms/Passes.td (-1)
• (modified) flang/include/flang/Tools/CLOptions.inc (+2-3)
• (modified) flang/lib/Optimizer/Transforms/ExternalNameConversion.cpp (+4-19)

diff --git a/flang/include/flang/Optimizer/Transforms/Passes.h b/flang/include/flang/Optimizer/Transforms/Passes.h
index a7ba704fdb39b..2d43f4d4c55b6 100644
--- a/flang/include/flang/Optimizer/Transforms/Passes.h
+++ b/flang/include/flang/Optimizer/Transforms/Passes.h
@@ -60,9 +60,6 @@ std::unique_ptr<mlir::Pass> createAffineDemotionPass();
 std::unique_ptr<mlir::Pass>
 createArrayValueCopyPass(fir::ArrayValueCopyOptions options = {});
 std::unique_ptr<mlir::Pass> createCFGConversionPassWithNSW();
-std::unique_ptr<mlir::Pass> createExternalNameConversionPass();
-std::unique_ptr<mlir::Pass>
-createExternalNameConversionPass(bool appendUnderscore);
 std::unique_ptr<mlir::Pass> createMemDataFlowOptPass();
 std::unique_ptr<mlir::Pass> createPromoteToAffinePass();
 std::unique_ptr<mlir::Pass>
diff --git a/flang/include/flang/Optimizer/Transforms/Passes.td b/flang/include/flang/Optimizer/Transforms/Passes.td
index 82638200e5e20..cac590a8da003 100644
--- a/flang/include/flang/Optimizer/Transforms/Passes.td
+++ b/flang/include/flang/Optimizer/Transforms/Passes.td
@@ -163,7 +163,6 @@ def ExternalNameConversion : Pass<"external-name-interop", "mlir::ModuleOp"> {
   let description = [{
     Demangle FIR internal name and mangle them for external interoperability.
   }];
-  let constructor = "::fir::createExternalNameConversionPass()";
   let options = [
     Option<"appendUnderscoreOpt", "append-underscore",
            "bool", /*default=*/"true",
diff --git a/flang/include/flang/Tools/CLOptions.inc b/flang/include/flang/Tools/CLOptions.inc
index c5c35e9a6a33f..d0399d65f5655 100644
--- a/flang/include/flang/Tools/CLOptions.inc
+++ b/flang/include/flang/Tools/CLOptions.inc
@@ -233,9 +233,8 @@ inline void addBoxedProcedurePass(mlir::PassManager &pm) {
 
 inline void addExternalNameConversionPass(
     mlir::PassManager &pm, bool appendUnderscore = true) {
-  addPassConditionally(pm, disableExternalNameConversion, [&]() {
-    return fir::createExternalNameConversionPass(appendUnderscore);
-  });
+  addPassConditionally(pm, disableExternalNameConversion,
+      [&]() { return fir::createExternalNameConversion({appendUnderscore}); });
 }
 
 // Use inliner extension point callback to register the default inliner pass.
diff --git a/flang/lib/Optimizer/Transforms/ExternalNameConversion.cpp b/flang/lib/Optimizer/Transforms/ExternalNameConversion.cpp
index b265c74c33dd5..648628fd1c9af 100644
--- a/flang/lib/Optimizer/Transforms/ExternalNameConversion.cpp
+++ b/flang/lib/Optimizer/Transforms/ExternalNameConversion.cpp
@@ -45,17 +45,11 @@ namespace {
 class ExternalNameConversionPass
     : public fir::impl::ExternalNameConversionBase<ExternalNameConversionPass> {
 public:
-  ExternalNameConversionPass(bool appendUnderscoring)
-      : appendUnderscores(appendUnderscoring) {}
-
-  ExternalNameConversionPass() { usePassOpt = true; }
+  using ExternalNameConversionBase<
+      ExternalNameConversionPass>::ExternalNameConversionBase;
 
   mlir::ModuleOp getModule() { return getOperation(); }
   void runOnOperation() override;
-
-private:
-  bool appendUnderscores;
-  bool usePassOpt = false;
 };
 } // namespace
 
@@ -63,7 +57,6 @@ void ExternalNameConversionPass::runOnOperation() {
   auto op = getOperation();
   auto *context = &getContext();
 
-  appendUnderscores = (usePassOpt) ? appendUnderscoreOpt : appendUnderscores;
   llvm::DenseMap<mlir::StringAttr, mlir::FlatSymbolRefAttr> remappings;
   // Update names of external Fortran functions and names of Common Block
   // globals.
@@ -74,7 +67,8 @@ void ExternalNameConversionPass::runOnOperation() {
           mlir::SymbolTable::getSymbolAttrName());
       auto deconstructedName = fir::NameUniquer::deconstruct(symName);
       if (fir::NameUniquer::isExternalFacingUniquedName(deconstructedName)) {
-        auto newName = mangleExternalName(deconstructedName, appendUnderscores);
+        auto newName =
+            mangleExternalName(deconstructedName, appendUnderscoreOpt);
         auto newAttr = mlir::StringAttr::get(context, newName);
         mlir::SymbolTable::setSymbolName(&funcOrGlobal, newAttr);
         auto newSymRef = mlir::FlatSymbolRefAttr::get(newAttr);
@@ -101,12 +95,3 @@ void ExternalNameConversionPass::runOnOperation() {
       nestedOp->setAttr(update.first, update.second);
   });
 }
-
-std::unique_ptr<mlir::Pass> fir::createExternalNameConversionPass() {
-  return std::make_unique<ExternalNameConversionPass>();
-}
-
-std::unique_ptr<mlir::Pass>
-fir::createExternalNameConversionPass(bool appendUnderscoring) {
-  return std::make_unique<ExternalNameConversionPass>(appendUnderscoring);
-}

[jeanPerier]

Thanks

[clementval]

LGTM