[flang][HLFIR] Adapt SimplifyHLFIRIntrinsics to run on all top level ops (#92573)

This means that this pass will also run on hlfir intrinsics which are
not inside of functions.

See RFC:

https://discourse.llvm.org/t/rfc-add-an-interface-for-top-level-container-operations

Some of the changes are from moving the declaration and definition of
the constructor into tablegen (as requested during code review of
another pass).

Author: tblah

flang/include/flang/Optimizer/HLFIR/Passes.h

@@ -25,7 +25,6 @@ namespace hlfir {
 std::unique_ptr<mlir::Pass> createConvertHLFIRtoFIRPass();
 std::unique_ptr<mlir::Pass> createBufferizeHLFIRPass();
 std::unique_ptr<mlir::Pass> createLowerHLFIRIntrinsicsPass();
-std::unique_ptr<mlir::Pass> createSimplifyHLFIRIntrinsicsPass();
 std::unique_ptr<mlir::Pass> createInlineElementalsPass();
 std::unique_ptr<mlir::Pass> createLowerHLFIROrderedAssignmentsPass();
 std::unique_ptr<mlir::Pass> createOptimizedBufferizationPass();

flang/include/flang/Optimizer/HLFIR/Passes.td

@@ -46,9 +46,8 @@ def LowerHLFIROrderedAssignments : Pass<"lower-hlfir-ordered-assignments", "::ml
   ];
 }
 
-def SimplifyHLFIRIntrinsics : Pass<"simplify-hlfir-intrinsics", "::mlir::func::FuncOp"> {
+def SimplifyHLFIRIntrinsics : Pass<"simplify-hlfir-intrinsics"> {
   let summary = "Simplify HLFIR intrinsic operations that don't need to result in runtime calls";
-  let constructor = "hlfir::createSimplifyHLFIRIntrinsicsPass()";
 }
 
 def InlineElementals : Pass<"inline-elementals", "::mlir::func::FuncOp"> {

flang/include/flang/Tools/CLOptions.inc

@@ -317,7 +317,8 @@ inline void createHLFIRToFIRPassPipeline(
     mlir::PassManager &pm, llvm::OptimizationLevel optLevel = defaultOptLevel) {
   if (optLevel.isOptimizingForSpeed()) {
     addCanonicalizerPassWithoutRegionSimplification(pm);
-    pm.addPass(hlfir::createSimplifyHLFIRIntrinsicsPass());
+    addNestedPassToAllTopLevelOperations(
+        pm, hlfir::createSimplifyHLFIRIntrinsics);
   }
   pm.addPass(hlfir::createInlineElementalsPass());
   if (optLevel.isOptimizingForSpeed()) {

flang/lib/Optimizer/HLFIR/Transforms/SimplifyHLFIRIntrinsics.cpp

@@ -94,7 +94,6 @@ class SimplifyHLFIRIntrinsics
     : public hlfir::impl::SimplifyHLFIRIntrinsicsBase<SimplifyHLFIRIntrinsics> {
 public:
   void runOnOperation() override {
-    mlir::func::FuncOp func = this->getOperation();
     mlir::MLIRContext *context = &getContext();
     mlir::RewritePatternSet patterns(context);
     patterns.insert<TransposeAsElementalConversion>(context);
@@ -108,16 +107,12 @@ class SimplifyHLFIRIntrinsics
         });
     target.markUnknownOpDynamicallyLegal(
         [](mlir::Operation *) { return true; });
-    if (mlir::failed(
-            mlir::applyFullConversion(func, target, std::move(patterns)))) {
-      mlir::emitError(func->getLoc(),
+    if (mlir::failed(mlir::applyFullConversion(getOperation(), target,
+                                               std::move(patterns)))) {
+      mlir::emitError(getOperation()->getLoc(),
                       "failure in HLFIR intrinsic simplification");
       signalPassFailure();
     }
   }
 };
 } // namespace
-
-std::unique_ptr<mlir::Pass> hlfir::createSimplifyHLFIRIntrinsicsPass() {
-  return std::make_unique<SimplifyHLFIRIntrinsics>();
-}

flang/test/Driver/mlir-pass-pipeline.f90

@@ -13,9 +13,16 @@
 
 ! ALL: Fortran::lower::VerifierPass
 ! O2-NEXT: Canonicalizer
-! O2-NEXT: 'func.func' Pipeline
+! O2-NEXT: Pipeline Collection : ['fir.global', 'func.func', 'omp.declare_reduction', 'omp.private']
+! O2-NEXT: 'fir.global' Pipeline
+! O2-NEXT:   SimplifyHLFIRIntrinsics
+! ALL:     'func.func' Pipeline
 ! O2-NEXT:   SimplifyHLFIRIntrinsics
 ! ALL:       InlineElementals
+! O2-NEXT: 'omp.declare_reduction' Pipeline
+! O2-NEXT:   SimplifyHLFIRIntrinsics
+! O2-NEXT: 'omp.private' Pipeline
+! O2-NEXT:   SimplifyHLFIRIntrinsics
 ! ALL: LowerHLFIROrderedAssignments
 ! ALL-NEXT: LowerHLFIRIntrinsics
 ! ALL-NEXT: BufferizeHLFIR

flang/test/Fir/basic-program.fir

@@ -17,9 +17,16 @@ func.func @_QQmain() {
 // PASSES: Pass statistics report
 
 // PASSES:        Canonicalizer
+// PASSES-NEXT: Pipeline Collection : ['fir.global', 'func.func', 'omp.declare_reduction', 'omp.private']
+// PASSES-NEXT: 'fir.global' Pipeline
+// PASSES-NEXT:   SimplifyHLFIRIntrinsics
 // PASSES-NEXT: 'func.func' Pipeline
 // PASSES-NEXT:   SimplifyHLFIRIntrinsics
 // PASSES-NEXT:   InlineElementals
+// PASSES-NEXT: 'omp.declare_reduction' Pipeline
+// PASSES-NEXT:   SimplifyHLFIRIntrinsics
+// PASSES-NEXT: 'omp.private' Pipeline
+// PASSES-NEXT:   SimplifyHLFIRIntrinsics
 // PASSES-NEXT:   Canonicalizer
 // PASSES-NEXT:   CSE
 // PASSES-NEXT:    (S) 0 num-cse'd - Number of operations CSE'd