[clang] [mlir] [CIR][OpenMP] Initial implementation of target region support (PR #195452)

[Sergio Afonso via cfe-commits]

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@@ -0,0 +1,89 @@
+//===--- CIRGenOpenMPClause.h - OpenMP clause emitter -----------*- C++ -*-===//
+//
+// 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 LLVM_CLANG_LIB_CIR_CODEGEN_CIRGENOPENMPCLAUSE_H
+#define LLVM_CLANG_LIB_CIR_CODEGEN_CIRGENOPENMPCLAUSE_H
+
+#include "CIRGenBuilder.h"
+#include "CIRGenModule.h"
+#include "mlir/Dialect/OpenMP/OpenMPClauseOperands.h"
+#include "clang/AST/OpenMPClause.h"
+#include "clang/AST/StmtOpenMP.h"
+#include "llvm/Frontend/OpenMP/OMPConstants.h"
+
+#include <type_traits>
+
+namespace clang::CIRGen {
+
+class CIRGenFunction;
+
+/// A type-only list of OpenMP clause AST node types.
+/// Note: The clause AST classes do not have a default constructor, so a
+/// std::tuple is not practical.
+template <typename... Clauses> struct OpenMPClauseList {};
+
+/// Emits OpenMP clauses for a directive, writing results into the
+/// auto-generated ClauseOps from the OMP dialect.
+class OpenMPClauseEmitter {
+  CIRGenFunction &cgf;
+  CIRGenModule &cgm;
+  CIRGenBuilderTy &builder;
+  mlir::Location loc;
+  llvm::ArrayRef<const OMPClause *> clauses;
+
+public:
+  OpenMPClauseEmitter(CIRGenFunction &cgf, CIRGenModule &cgm,
+                      CIRGenBuilderTy &builder, mlir::Location loc,
+                      llvm::ArrayRef<const OMPClause *> clauses)
+      : cgf(cgf), cgm(cgm), builder(builder), loc(loc), clauses(clauses) {}
+
+  bool emitProcBind(mlir::omp::ProcBindClauseOps &result) const;
+
+  /// Emit map clauses. The optional \p mapSyms parameter collects the
+  /// VarDecls corresponding to each map operand.
+  bool emitMap(mlir::omp::MapClauseOps &result,
+               llvm::SmallVectorImpl<const VarDecl *> *mapSyms = nullptr) const;
+
+  /// Verify the clauses of a directive to make sure all legal cases are either
+  /// implemented or give a NYI error. If the clause is neither, then
+  /// an unknown clause error will be emitted.
----------------
skatrak wrote:

```suggestion
  /// implemented or give a NYI error. The \p SupportedClauses and \p NYIClauses type lists must be disjoint and cover all clauses eligible for the directive being processed.
```

https://github.com/llvm/llvm-project/pull/195452