[OPENMP] Initial support for 'task_reduction' clause.

Parsing/sema analysis of the 'task_reduction' clause.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@308352 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/AST/OpenMPClause.h

@@ -1890,6 +1890,217 @@ class OMPReductionClause final
   }
 };
 
+/// This represents clause 'task_reduction' in the '#pragma omp taskgroup'
+/// directives.
+///
+/// \code
+/// #pragma omp taskgroup task_reduction(+:a,b)
+/// \endcode
+/// In this example directive '#pragma omp taskgroup' has clause
+/// 'task_reduction' with operator '+' and the variables 'a' and 'b'.
+///
+class OMPTaskReductionClause final
+    : public OMPVarListClause<OMPTaskReductionClause>,
+      public OMPClauseWithPostUpdate,
+      private llvm::TrailingObjects<OMPTaskReductionClause, Expr *> {
+  friend TrailingObjects;
+  friend OMPVarListClause;
+  friend class OMPClauseReader;
+  /// Location of ':'.
+  SourceLocation ColonLoc;
+  /// Nested name specifier for C++.
+  NestedNameSpecifierLoc QualifierLoc;
+  /// Name of custom operator.
+  DeclarationNameInfo NameInfo;
+
+  /// Build clause with number of variables \a N.
+  ///
+  /// \param StartLoc Starting location of the clause.
+  /// \param LParenLoc Location of '('.
+  /// \param EndLoc Ending location of the clause.
+  /// \param ColonLoc Location of ':'.
+  /// \param N Number of the variables in the clause.
+  /// \param QualifierLoc The nested-name qualifier with location information
+  /// \param NameInfo The full name info for reduction identifier.
+  ///
+  OMPTaskReductionClause(SourceLocation StartLoc, SourceLocation LParenLoc,
+                         SourceLocation ColonLoc, SourceLocation EndLoc,
+                         unsigned N, NestedNameSpecifierLoc QualifierLoc,
+                         const DeclarationNameInfo &NameInfo)
+      : OMPVarListClause<OMPTaskReductionClause>(OMPC_task_reduction, StartLoc,
+                                                 LParenLoc, EndLoc, N),
+        OMPClauseWithPostUpdate(this), ColonLoc(ColonLoc),
+        QualifierLoc(QualifierLoc), NameInfo(NameInfo) {}
+
+  /// Build an empty clause.
+  ///
+  /// \param N Number of variables.
+  ///
+  explicit OMPTaskReductionClause(unsigned N)
+      : OMPVarListClause<OMPTaskReductionClause>(
+            OMPC_task_reduction, SourceLocation(), SourceLocation(),
+            SourceLocation(), N),
+        OMPClauseWithPostUpdate(this), ColonLoc(), QualifierLoc(), NameInfo() {}
+
+  /// Sets location of ':' symbol in clause.
+  void setColonLoc(SourceLocation CL) { ColonLoc = CL; }
+  /// Sets the name info for specified reduction identifier.
+  void setNameInfo(DeclarationNameInfo DNI) { NameInfo = DNI; }
+  /// Sets the nested name specifier.
+  void setQualifierLoc(NestedNameSpecifierLoc NSL) { QualifierLoc = NSL; }
+
+  /// Set list of helper expressions, required for proper codegen of the clause.
+  /// These expressions represent private copy of the reduction variable.
+  void setPrivates(ArrayRef<Expr *> Privates);
+
+  /// Get the list of helper privates.
+  MutableArrayRef<Expr *> getPrivates() {
+    return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
+  }
+  ArrayRef<const Expr *> getPrivates() const {
+    return llvm::makeArrayRef(varlist_end(), varlist_size());
+  }
+
+  /// Set list of helper expressions, required for proper codegen of the clause.
+  /// These expressions represent LHS expression in the final reduction
+  /// expression performed by the reduction clause.
+  void setLHSExprs(ArrayRef<Expr *> LHSExprs);
+
+  /// Get the list of helper LHS expressions.
+  MutableArrayRef<Expr *> getLHSExprs() {
+    return MutableArrayRef<Expr *>(getPrivates().end(), varlist_size());
+  }
+  ArrayRef<const Expr *> getLHSExprs() const {
+    return llvm::makeArrayRef(getPrivates().end(), varlist_size());
+  }
+
+  /// Set list of helper expressions, required for proper codegen of the clause.
+  /// These expressions represent RHS expression in the final reduction
+  /// expression performed by the reduction clause. Also, variables in these
+  /// expressions are used for proper initialization of reduction copies.
+  void setRHSExprs(ArrayRef<Expr *> RHSExprs);
+
+  ///  Get the list of helper destination expressions.
+  MutableArrayRef<Expr *> getRHSExprs() {
+    return MutableArrayRef<Expr *>(getLHSExprs().end(), varlist_size());
+  }
+  ArrayRef<const Expr *> getRHSExprs() const {
+    return llvm::makeArrayRef(getLHSExprs().end(), varlist_size());
+  }
+
+  /// Set list of helper reduction expressions, required for proper
+  /// codegen of the clause. These expressions are binary expressions or
+  /// operator/custom reduction call that calculates new value from source
+  /// helper expressions to destination helper expressions.
+  void setReductionOps(ArrayRef<Expr *> ReductionOps);
+
+  ///  Get the list of helper reduction expressions.
+  MutableArrayRef<Expr *> getReductionOps() {
+    return MutableArrayRef<Expr *>(getRHSExprs().end(), varlist_size());
+  }
+  ArrayRef<const Expr *> getReductionOps() const {
+    return llvm::makeArrayRef(getRHSExprs().end(), varlist_size());
+  }
+
+public:
+  /// Creates clause with a list of variables \a VL.
+  ///
+  /// \param StartLoc Starting location of the clause.
+  /// \param LParenLoc Location of '('.
+  /// \param ColonLoc Location of ':'.
+  /// \param EndLoc Ending location of the clause.
+  /// \param VL The variables in the clause.
+  /// \param QualifierLoc The nested-name qualifier with location information
+  /// \param NameInfo The full name info for reduction identifier.
+  /// \param Privates List of helper expressions for proper generation of
+  /// private copies.
+  /// \param LHSExprs List of helper expressions for proper generation of
+  /// assignment operation required for copyprivate clause. This list represents
+  /// LHSs of the reduction expressions.
+  /// \param RHSExprs List of helper expressions for proper generation of
+  /// assignment operation required for copyprivate clause. This list represents
+  /// RHSs of the reduction expressions.
+  /// Also, variables in these expressions are used for proper initialization of
+  /// reduction copies.
+  /// \param ReductionOps List of helper expressions that represents reduction
+  /// expressions:
+  /// \code
+  /// LHSExprs binop RHSExprs;
+  /// operator binop(LHSExpr, RHSExpr);
+  /// <CutomReduction>(LHSExpr, RHSExpr);
+  /// \endcode
+  /// Required for proper codegen of final reduction operation performed by the
+  /// reduction clause.
+  /// \param PreInit Statement that must be executed before entering the OpenMP
+  /// region with this clause.
+  /// \param PostUpdate Expression that must be executed after exit from the
+  /// OpenMP region with this clause.
+  ///
+  static OMPTaskReductionClause *
+  Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
+         SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef<Expr *> VL,
+         NestedNameSpecifierLoc QualifierLoc,
+         const DeclarationNameInfo &NameInfo, ArrayRef<Expr *> Privates,
+         ArrayRef<Expr *> LHSExprs, ArrayRef<Expr *> RHSExprs,
+         ArrayRef<Expr *> ReductionOps, Stmt *PreInit, Expr *PostUpdate);
+
+  /// Creates an empty clause with the place for \a N variables.
+  ///
+  /// \param C AST context.
+  /// \param N The number of variables.
+  ///
+  static OMPTaskReductionClause *CreateEmpty(const ASTContext &C, unsigned N);
+
+  /// Gets location of ':' symbol in clause.
+  SourceLocation getColonLoc() const { return ColonLoc; }
+  /// Gets the name info for specified reduction identifier.
+  const DeclarationNameInfo &getNameInfo() const { return NameInfo; }
+  /// Gets the nested name specifier.
+  NestedNameSpecifierLoc getQualifierLoc() const { return QualifierLoc; }
+
+  typedef MutableArrayRef<Expr *>::iterator helper_expr_iterator;
+  typedef ArrayRef<const Expr *>::iterator helper_expr_const_iterator;
+  typedef llvm::iterator_range<helper_expr_iterator> helper_expr_range;
+  typedef llvm::iterator_range<helper_expr_const_iterator>
+      helper_expr_const_range;
+
+  helper_expr_const_range privates() const {
+    return helper_expr_const_range(getPrivates().begin(), getPrivates().end());
+  }
+  helper_expr_range privates() {
+    return helper_expr_range(getPrivates().begin(), getPrivates().end());
+  }
+  helper_expr_const_range lhs_exprs() const {
+    return helper_expr_const_range(getLHSExprs().begin(), getLHSExprs().end());
+  }
+  helper_expr_range lhs_exprs() {
+    return helper_expr_range(getLHSExprs().begin(), getLHSExprs().end());
+  }
+  helper_expr_const_range rhs_exprs() const {
+    return helper_expr_const_range(getRHSExprs().begin(), getRHSExprs().end());
+  }
+  helper_expr_range rhs_exprs() {
+    return helper_expr_range(getRHSExprs().begin(), getRHSExprs().end());
+  }
+  helper_expr_const_range reduction_ops() const {
+    return helper_expr_const_range(getReductionOps().begin(),
+                                   getReductionOps().end());
+  }
+  helper_expr_range reduction_ops() {
+    return helper_expr_range(getReductionOps().begin(),
+                             getReductionOps().end());
+  }
+
+  child_range children() {
+    return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
+                       reinterpret_cast<Stmt **>(varlist_end()));
+  }
+
+  static bool classof(const OMPClause *T) {
+    return T->getClauseKind() == OMPC_task_reduction;
+  }
+};
+
 /// \brief This represents clause 'linear' in the '#pragma omp ...'
 /// directives.
 ///

include/clang/AST/RecursiveASTVisitor.h

@@ -3016,6 +3016,28 @@ RecursiveASTVisitor<Derived>::VisitOMPReductionClause(OMPReductionClause *C) {
   return true;
 }
 
+template <typename Derived>
+bool RecursiveASTVisitor<Derived>::VisitOMPTaskReductionClause(
+    OMPTaskReductionClause *C) {
+  TRY_TO(TraverseNestedNameSpecifierLoc(C->getQualifierLoc()));
+  TRY_TO(TraverseDeclarationNameInfo(C->getNameInfo()));
+  TRY_TO(VisitOMPClauseList(C));
+  TRY_TO(VisitOMPClauseWithPostUpdate(C));
+  for (auto *E : C->privates()) {
+    TRY_TO(TraverseStmt(E));
+  }
+  for (auto *E : C->lhs_exprs()) {
+    TRY_TO(TraverseStmt(E));
+  }
+  for (auto *E : C->rhs_exprs()) {
+    TRY_TO(TraverseStmt(E));
+  }
+  for (auto *E : C->reduction_ops()) {
+    TRY_TO(TraverseStmt(E));
+  }
+  return true;
+}
+
 template <typename Derived>
 bool RecursiveASTVisitor<Derived>::VisitOMPFlushClause(OMPFlushClause *C) {
   TRY_TO(VisitOMPClauseList(C));

include/clang/AST/StmtOpenMP.h

@@ -1895,47 +1895,53 @@ class OMPTaskwaitDirective : public OMPExecutableDirective {
   }
 };
 
-/// \brief This represents '#pragma omp taskgroup' directive.
+/// This represents '#pragma omp taskgroup' directive.
 ///
 /// \code
 /// #pragma omp taskgroup
 /// \endcode
 ///
 class OMPTaskgroupDirective : public OMPExecutableDirective {
   friend class ASTStmtReader;
-  /// \brief Build directive with the given start and end location.
+  /// Build directive with the given start and end location.
   ///
   /// \param StartLoc Starting location of the directive kind.
   /// \param EndLoc Ending location of the directive.
+  /// \param NumClauses Number of clauses.
   ///
-  OMPTaskgroupDirective(SourceLocation StartLoc, SourceLocation EndLoc)
+  OMPTaskgroupDirective(SourceLocation StartLoc, SourceLocation EndLoc,
+                        unsigned NumClauses)
       : OMPExecutableDirective(this, OMPTaskgroupDirectiveClass, OMPD_taskgroup,
-                               StartLoc, EndLoc, 0, 1) {}
+                               StartLoc, EndLoc, NumClauses, 1) {}
 
-  /// \brief Build an empty directive.
+  /// Build an empty directive.
+  /// \param NumClauses Number of clauses.
   ///
-  explicit OMPTaskgroupDirective()
+  explicit OMPTaskgroupDirective(unsigned NumClauses)
       : OMPExecutableDirective(this, OMPTaskgroupDirectiveClass, OMPD_taskgroup,
-                               SourceLocation(), SourceLocation(), 0, 1) {}
+                               SourceLocation(), SourceLocation(), NumClauses,
+                               1) {}
 
 public:
-  /// \brief Creates directive.
+  /// Creates directive.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the directive kind.
   /// \param EndLoc Ending Location of the directive.
+  /// \param Clauses List of clauses.
   /// \param AssociatedStmt Statement, associated with the directive.
   ///
-  static OMPTaskgroupDirective *Create(const ASTContext &C,
-                                       SourceLocation StartLoc,
-                                       SourceLocation EndLoc,
-                                       Stmt *AssociatedStmt);
+  static OMPTaskgroupDirective *
+  Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation EndLoc,
+         ArrayRef<OMPClause *> Clauses, Stmt *AssociatedStmt);
 
-  /// \brief Creates an empty directive.
+  /// Creates an empty directive.
   ///
   /// \param C AST context.
+  /// \param NumClauses Number of clauses.
   ///
-  static OMPTaskgroupDirective *CreateEmpty(const ASTContext &C, EmptyShell);
+  static OMPTaskgroupDirective *CreateEmpty(const ASTContext &C,
+                                            unsigned NumClauses, EmptyShell);
 
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == OMPTaskgroupDirectiveClass;

include/clang/Basic/DiagnosticSemaKinds.td

@@ -8655,11 +8655,11 @@ def err_omp_unknown_reduction_identifier : Error<
 def err_omp_not_resolved_reduction_identifier : Error<
   "unable to resolve declare reduction construct for type %0">;
 def err_omp_reduction_ref_type_arg : Error<
-  "argument of OpenMP clause 'reduction' must reference the same object in all threads">;
+  "argument of OpenMP clause '%0' must reference the same object in all threads">;
 def err_omp_clause_not_arithmetic_type_arg : Error<
-  "arguments of OpenMP clause 'reduction' for 'min' or 'max' must be of %select{scalar|arithmetic}0 type">;
+  "arguments of OpenMP clause '%0' for 'min' or 'max' must be of %select{scalar|arithmetic}1 type">;
 def err_omp_clause_floating_type_arg : Error<
-  "arguments of OpenMP clause 'reduction' with bitwise operators cannot be of floating type">;
+  "arguments of OpenMP clause '%0' with bitwise operators cannot be of floating type">;
 def err_omp_once_referenced : Error<
   "variable can appear only once in OpenMP '%0' clause">;
 def err_omp_once_referenced_in_target_update : Error<

include/clang/Basic/OpenMPKinds.def

@@ -168,6 +168,9 @@
 #ifndef OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE
 #define OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(Name)
 #endif
+#ifndef OPENMP_TASKGROUP_CLAUSE
+#define OPENMP_TASKGROUP_CLAUSE(Name)
+#endif
 
 // OpenMP directives.
 OPENMP_DIRECTIVE(threadprivate)
@@ -270,6 +273,7 @@ OPENMP_CLAUSE(to, OMPToClause)
 OPENMP_CLAUSE(from, OMPFromClause)
 OPENMP_CLAUSE(use_device_ptr, OMPUseDevicePtrClause)
 OPENMP_CLAUSE(is_device_ptr, OMPIsDevicePtrClause)
+OPENMP_CLAUSE(task_reduction,  OMPTaskReductionClause)
 
 // Clauses allowed for OpenMP directive 'parallel'.
 OPENMP_PARALLEL_CLAUSE(if)
@@ -848,6 +852,10 @@ OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(aligned)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(safelen)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(simdlen)
 
+// Clauses allowed for OpenMP directive 'taskgroup'.
+OPENMP_TASKGROUP_CLAUSE(task_reduction)
+
+#undef OPENMP_TASKGROUP_CLAUSE
 #undef OPENMP_TASKLOOP_SIMD_CLAUSE
 #undef OPENMP_TASKLOOP_CLAUSE
 #undef OPENMP_LINEAR_KIND

include/clang/Sema/Sema.h

@@ -8682,7 +8682,8 @@ class Sema {
   StmtResult ActOnOpenMPTaskwaitDirective(SourceLocation StartLoc,
                                           SourceLocation EndLoc);
   /// \brief Called on well-formed '\#pragma omp taskgroup'.
-  StmtResult ActOnOpenMPTaskgroupDirective(Stmt *AStmt, SourceLocation StartLoc,
+  StmtResult ActOnOpenMPTaskgroupDirective(ArrayRef<OMPClause *> Clauses,
+                                           Stmt *AStmt, SourceLocation StartLoc,
                                            SourceLocation EndLoc);
   /// \brief Called on well-formed '\#pragma omp flush'.
   StmtResult ActOnOpenMPFlushDirective(ArrayRef<OMPClause *> Clauses,
@@ -9024,6 +9025,13 @@ class Sema {
       CXXScopeSpec &ReductionIdScopeSpec,
       const DeclarationNameInfo &ReductionId,
       ArrayRef<Expr *> UnresolvedReductions = llvm::None);
+  /// Called on well-formed 'task_reduction' clause.
+  OMPClause *ActOnOpenMPTaskReductionClause(
+      ArrayRef<Expr *> VarList, SourceLocation StartLoc,
+      SourceLocation LParenLoc, SourceLocation ColonLoc, SourceLocation EndLoc,
+      CXXScopeSpec &ReductionIdScopeSpec,
+      const DeclarationNameInfo &ReductionId,
+      ArrayRef<Expr *> UnresolvedReductions = llvm::None);
   /// \brief Called on well-formed 'linear' clause.
   OMPClause *
   ActOnOpenMPLinearClause(ArrayRef<Expr *> VarList, Expr *Step,