[clang] [OpenACC] Implement AST for OpenACC Compute Constructs (PR #81188)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,142 @@
+//===- StmtOpenACC.h - Classes for OpenACC directives  ----------*- 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
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file defines OpenACC AST classes for statement-level contructs.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_STMTOPENACC_H
+#define LLVM_CLANG_AST_STMTOPENACC_H
+
+#include "clang/AST/Stmt.h"
+#include "clang/Basic/OpenACCKinds.h"
+#include "clang/Basic/SourceLocation.h"
+
+namespace clang {
+/// This is the base class for an OpenACC statement-level construct, other
+/// construct types are expected to inherit from this.
+class OpenACCConstructStmt : public Stmt {
+  friend class ASTStmtWriter;
+  friend class ASTStmtReader;
+  /// The directive kind. Each implementation of this interface should handle
+  /// specific kinds.
+  OpenACCDirectiveKind Kind = OpenACCDirectiveKind::Invalid;
+  /// The location of the directive statement, from the '#' to the last token of
+  /// the directive.
+  SourceRange Range;
+
+  // TODO OPENACC: Clauses should probably be collected in this class.
+
+protected:
+  OpenACCConstructStmt(StmtClass SC, OpenACCDirectiveKind K,
+                       SourceLocation Start, SourceLocation End)
+      : Stmt(SC), Kind(K), Range(Start, End) {}
+
+public:
+  OpenACCDirectiveKind getDirectiveKind() const { return Kind; }
+
+  static bool classof(const Stmt *S) {
+    return S->getStmtClass() >= firstOpenACCConstructStmtConstant &&
+           S->getStmtClass() <= lastOpenACCConstructStmtConstant;
+  }
+
+  SourceLocation getBeginLoc() const { return Range.getBegin(); }
+  SourceLocation getEndLoc() const { return Range.getEnd(); }
+
+  child_range children() {
+    return child_range(child_iterator(), child_iterator());
+  }
+
+  const_child_range children() const {
+    return const_cast<OpenACCConstructStmt *>(this)->children();
+  }
+};
+
+/// This is a base class for any OpenACC statement-level constructs that have an
+/// associated statement. This class is not intended to be instantiated, but is
+/// a convenient place to hold the associated statement.
+class OpenACCAssociatedStmtConstruct : public OpenACCConstructStmt {
+  friend class ASTStmtWriter;
+  friend class ASTStmtReader;
+  template <typename Derived> friend class RecursiveASTVisitor;
+  Stmt *AssociatedStmt = nullptr;
----------------
erichkeane wrote:

As far as I can tell, they do NOT have any.  Individual clauses have expressions (and some of the other nodes have expressions), but there is never more than 1 statement associated with it.

I considered the trailing storage, but since it is always 'required' and only on certain constructs  (which I'll select via giving them a different AST node), I think a member for the `ComputeConstruct`, and a few others makes the most sense?  But if you see a good reason to switch to trailing storage during future review, please let me know, and I'll switch it over!

https://github.com/llvm/llvm-project/pull/81188