[clang] [Clang][OpenMP] Allow `num_teams` to accept multiple expressions (PR #99732)

[Alexey Bataev via cfe-commits]

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@@ -6131,60 +6131,77 @@ class OMPMapClause final : public OMPMappableExprListClause<OMPMapClause>,
 /// \endcode
 /// In this example directive '#pragma omp teams' has clause 'num_teams'
 /// with single expression 'n'.
-class OMPNumTeamsClause : public OMPClause, public OMPClauseWithPreInit {
-  friend class OMPClauseReader;
+///
+/// When 'ompx_bare' clause exists on a 'target' directive, 'num_teams' clause
+/// can accept up to three expressions.
+///
+/// \code
+/// #pragma omp target teams ompx_bare num_teams(x, y, z)
+/// \endcode
+class OMPNumTeamsClause final
+    : public OMPVarListClause<OMPNumTeamsClause>,
+      public OMPClauseWithPreInit,
+      private llvm::TrailingObjects<OMPNumTeamsClause, Expr *> {
+  friend OMPVarListClause;
+  friend TrailingObjects;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
-  /// NumTeams number.
-  Stmt *NumTeams = nullptr;
+  OMPNumTeamsClause(const ASTContext &C, SourceLocation StartLoc,
+                    SourceLocation LParenLoc, SourceLocation EndLoc, unsigned N)
+      : OMPVarListClause(llvm::omp::OMPC_num_teams, StartLoc, LParenLoc, EndLoc,
+                         N),
+        OMPClauseWithPreInit(this) {}
 
-  /// Set the NumTeams number.
-  ///
-  /// \param E NumTeams number.
-  void setNumTeams(Expr *E) { NumTeams = E; }
+  /// Build an empty clause.
+  OMPNumTeamsClause(unsigned N)
+      : OMPVarListClause(llvm::omp::OMPC_num_teams, SourceLocation(),
+                         SourceLocation(), SourceLocation(), N),
+        OMPClauseWithPreInit(this) {}
 
 public:
-  /// Build 'num_teams' clause.
+  /// Creates clause with a list of variables \a VL.
   ///
-  /// \param E Expression associated with this clause.
-  /// \param HelperE Helper Expression associated with this clause.
-  /// \param CaptureRegion Innermost OpenMP region where expressions in this
-  /// clause must be captured.
+  /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
-  OMPNumTeamsClause(Expr *E, Stmt *HelperE, OpenMPDirectiveKind CaptureRegion,
-                    SourceLocation StartLoc, SourceLocation LParenLoc,
-                    SourceLocation EndLoc)
-      : OMPClause(llvm::omp::OMPC_num_teams, StartLoc, EndLoc),
-        OMPClauseWithPreInit(this), LParenLoc(LParenLoc), NumTeams(E) {
-    setPreInitStmt(HelperE, CaptureRegion);
-  }
+  /// \param VL List of references to the variables.
+  /// \param PreInit
+  static OMPNumTeamsClause *Create(const ASTContext &C, SourceLocation StartLoc,
+                                   SourceLocation LParenLoc,
+                                   SourceLocation EndLoc, ArrayRef<Expr *> VL,
+                                   Stmt *PreInit);
 
-  /// Build an empty clause.
-  OMPNumTeamsClause()
-      : OMPClause(llvm::omp::OMPC_num_teams, SourceLocation(),
-                  SourceLocation()),
-        OMPClauseWithPreInit(this) {}
+  /// Creates an empty clause with \a N variables.
+  ///
+  /// \param C AST context.
+  /// \param N The number of variables.
+  static OMPNumTeamsClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
-  /// Return NumTeams number.
-  Expr *getNumTeams() { return cast<Expr>(NumTeams); }
+  /// Return NumTeams number. By default, we return the first expression.
+  Expr *getNumTeams() { return getVarRefs().front(); }
 
-  /// Return NumTeams number.
-  Expr *getNumTeams() const { return cast<Expr>(NumTeams); }
+  /// Return NumTeams number. By default, we return the first expression.
+  Expr *getNumTeams() const {
+    return const_cast<OMPNumTeamsClause *>(this)->getNumTeams();
+  }
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alexey-bataev wrote:

I think these should return ArrayRef

https://github.com/llvm/llvm-project/pull/99732