[flang] [llvm] [flang][OpenMP] Decompose compound constructs, do recursive lowering (PR #90098)

[Kareem Ergawy via llvm-commits]

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@@ -0,0 +1,44 @@
+//===-- Decomposer.h -- Compound directive decomposition ------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef FORTRAN_LOWER_OPENMP_DECOMPOSER_H
+#define FORTRAN_LOWER_OPENMP_DECOMPOSER_H
+
+#include "Clauses.h"
+#include "mlir/IR/BuiltinOps.h"
+#include "llvm/Frontend/OpenMP/ConstructDecompositionT.h"
+#include "llvm/Frontend/OpenMP/OMP.h"
+#include "llvm/Support/Compiler.h"
+
+namespace llvm {
+class raw_ostream;
+}
+
+namespace Fortran {
+namespace semantics {
+class SemanticsContext;
+}
+namespace lower::pft {
+struct Evaluation;
+}
+} // namespace Fortran
+
+namespace Fortran::lower::omp {
+using UnitConstruct = tomp::DirectiveWithClauses<lower::omp::Clause>;
+using ConstructQueue = List<UnitConstruct>;
+
+LLVM_DUMP_METHOD llvm::raw_ostream &operator<<(llvm::raw_ostream &os,
+                                               const UnitConstruct &uc);
+
+ConstructQueue
+buildConstructQueue(mlir::ModuleOp modOp,
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ergawy wrote:

Can you add docs with example input(s) & expected output(s) of this function? Just to clarify its meaning/purpose more concretely.

https://github.com/llvm/llvm-project/pull/90098