[OPENMP] parsing 'linear' clause (for directive 'omp simd')

Differential Revision: http://reviews.llvm.org/D3272

llvm-svn: 206891

clang/include/clang/AST/DataRecursiveASTVisitor.h

@@ -2405,6 +2405,14 @@ bool DataRecursiveASTVisitor<Derived>::VisitOMPSharedClause(OMPSharedClause *C)
   return true;
 }
 
+template<typename Derived>
+bool
+DataRecursiveASTVisitor<Derived>::VisitOMPLinearClause(OMPLinearClause *C) {
+  VisitOMPClauseList(C);
+  TraverseStmt(C->getStep());
+  return true;
+}
+
 template<typename Derived>
 bool DataRecursiveASTVisitor<Derived>::VisitOMPCopyinClause(OMPCopyinClause *C) {
   VisitOMPClauseList(C);

clang/include/clang/AST/OpenMPClause.h

@@ -553,6 +553,91 @@ class OMPSharedClause : public OMPVarListClause<OMPSharedClause> {
   }
 };
 
+/// \brief This represents clause 'linear' in the '#pragma omp ...'
+/// directives.
+///
+/// \code
+/// #pragma omp simd linear(a,b : 2)
+/// \endcode
+/// In this example directive '#pragma omp simd' has clause 'linear'
+/// with variables 'a', 'b' and linear step '2'.
+///
+class OMPLinearClause : public OMPVarListClause<OMPLinearClause> {
+  friend class OMPClauseReader;
+  /// \brief Location of ':'.
+  SourceLocation ColonLoc;
+
+  /// \brief Sets the linear step for clause.
+  void setStep(Expr *Step) { *varlist_end() = Step; }
+
+  /// \brief Build 'linear' clause with given number of variables \a NumVars.
+  ///
+  /// \param StartLoc Starting location of the clause.
+  /// \param LParenLoc Location of '('.
+  /// \param ColonLoc Location of ':'.
+  /// \param EndLoc Ending location of the clause.
+  /// \param NumVars Number of variables.
+  ///
+  OMPLinearClause(SourceLocation StartLoc, SourceLocation LParenLoc,
+                  SourceLocation ColonLoc, SourceLocation EndLoc,
+                  unsigned NumVars)
+      : OMPVarListClause<OMPLinearClause>(OMPC_linear, StartLoc, LParenLoc,
+                                          EndLoc, NumVars),
+        ColonLoc(ColonLoc) {}
+
+  /// \brief Build an empty clause.
+  ///
+  /// \param NumVars Number of variables.
+  ///
+  explicit OMPLinearClause(unsigned NumVars)
+      : OMPVarListClause<OMPLinearClause>(OMPC_linear, SourceLocation(),
+                                          SourceLocation(), SourceLocation(),
+                                          NumVars),
+        ColonLoc(SourceLocation()) {}
+
+public:
+  /// \brief Creates clause with a list of variables \a VL and a linear step
+  /// \a Step.
+  ///
+  /// \param C AST Context.
+  /// \param StartLoc Starting location of the clause.
+  /// \param LParenLoc Location of '('.
+  /// \param ColonLoc Location of ':'.
+  /// \param EndLoc Ending location of the clause.
+  /// \param VL List of references to the variables.
+  /// \param Step Linear step.
+  static OMPLinearClause *Create(const ASTContext &C, SourceLocation StartLoc,
+                                 SourceLocation LParenLoc,
+                                 SourceLocation ColonLoc, SourceLocation EndLoc,
+                                 ArrayRef<Expr *> VL, Expr *Step);
+
+  /// \brief Creates an empty clause with the place for \a NumVars variables.
+  ///
+  /// \param C AST context.
+  /// \param NumVars Number of variables.
+  ///
+  static OMPLinearClause *CreateEmpty(const ASTContext &C, unsigned NumVars);
+
+  /// \brief Sets the location of ':'.
+  void setColonLoc(SourceLocation Loc) { ColonLoc = Loc; }
+  /// \brief Returns the location of '('.
+  SourceLocation getColonLoc() const { return ColonLoc; }
+
+  /// \brief Returns linear step.
+  Expr *getStep() { return *varlist_end(); }
+  /// \brief Returns linear step.
+  const Expr *getStep() const { return *varlist_end(); }
+
+  StmtRange children() {
+    return StmtRange(reinterpret_cast<Stmt **>(varlist_begin()),
+                     reinterpret_cast<Stmt **>(varlist_end() + 1));
+  }
+
+  static bool classof(const OMPClause *T) {
+    return T->getClauseKind() == OMPC_linear;
+  }
+};
+
 /// \brief This represents clause 'copyin' in the '#pragma omp ...' directives.
 ///
 /// \code

clang/include/clang/AST/RecursiveASTVisitor.h

@@ -2442,6 +2442,13 @@ bool RecursiveASTVisitor<Derived>::VisitOMPSharedClause(OMPSharedClause *C) {
   return true;
 }
 
+template<typename Derived>
+bool RecursiveASTVisitor<Derived>::VisitOMPLinearClause(OMPLinearClause *C) {
+  VisitOMPClauseList(C);
+  TraverseStmt(C->getStep());
+  return true;
+}
+
 template<typename Derived>
 bool RecursiveASTVisitor<Derived>::VisitOMPCopyinClause(OMPCopyinClause *C) {
   VisitOMPClauseList(C);

clang/include/clang/Basic/DiagnosticGroups.td

@@ -671,6 +671,7 @@ def ASM : DiagGroup<"asm", [
 
 // OpenMP warnings.
 def SourceUsesOpenMP : DiagGroup<"source-uses-openmp">;
+def OpenMPClauses : DiagGroup<"openmp-clauses">;
 
 // Backend warnings.
 def BackendInlineAsm : DiagGroup<"inline-asm">;

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -6928,6 +6928,16 @@ def err_omp_ambiguous_conversion : Error<
   "enumeration type">;
 def err_omp_required_access : Error<
   "%0 variable must be %1">;
+def err_omp_const_variable : Error<
+  "const-qualified variable cannot be %0">;
+def err_omp_linear_incomplete_type : Error<
+  "a linear variable with incomplete type %0">;
+def err_omp_linear_expected_int_or_ptr : Error<
+  "argument of a linear clause should be of integral or pointer "
+  "type, not %0">;
+def warn_omp_linear_step_zero : Warning<
+  "zero linear step (%0 %select{|and other variables in clause }1should probably be const)">,
+  InGroup<OpenMPClauses>;
 } // end of OpenMP category
 
 let CategoryName = "Related Result Type Issue" in {

clang/include/clang/Basic/OpenMPKinds.def

@@ -42,6 +42,7 @@ OPENMP_CLAUSE(default, OMPDefaultClause)
 OPENMP_CLAUSE(private, OMPPrivateClause)
 OPENMP_CLAUSE(firstprivate, OMPFirstprivateClause)
 OPENMP_CLAUSE(shared,  OMPSharedClause)
+OPENMP_CLAUSE(linear,  OMPLinearClause)
 OPENMP_CLAUSE(copyin,  OMPCopyinClause)
 
 // Clauses allowed for OpenMP directive 'parallel'.
@@ -55,6 +56,7 @@ OPENMP_PARALLEL_CLAUSE(copyin)
 
 // FIXME: more clauses allowed for directive 'omp simd'.
 OPENMP_SIMD_CLAUSE(private)
+OPENMP_SIMD_CLAUSE(linear)
 OPENMP_SIMD_CLAUSE(safelen)
 
 // Static attributes for 'default' clause.

clang/include/clang/Sema/Sema.h

@@ -7286,8 +7286,10 @@ class Sema {
 
   OMPClause *ActOnOpenMPVarListClause(OpenMPClauseKind Kind,
                                       ArrayRef<Expr *> Vars,
+                                      Expr *TailExpr,
                                       SourceLocation StartLoc,
                                       SourceLocation LParenLoc,
+                                      SourceLocation ColonLoc,
                                       SourceLocation EndLoc);
   /// \brief Called on well-formed 'private' clause.
   OMPClause *ActOnOpenMPPrivateClause(ArrayRef<Expr *> VarList,
@@ -7304,6 +7306,13 @@ class Sema {
                                      SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
                                      SourceLocation EndLoc);
+  /// \brief Called on well-formed 'linear' clause.
+  OMPClause *ActOnOpenMPLinearClause(ArrayRef<Expr *> VarList,
+                                     Expr *Step,
+                                     SourceLocation StartLoc,
+                                     SourceLocation LParenLoc,
+                                     SourceLocation ColonLoc,
+                                     SourceLocation EndLoc);
   /// \brief Called on well-formed 'copyin' clause.
   OMPClause *ActOnOpenMPCopyinClause(ArrayRef<Expr *> VarList,
                                      SourceLocation StartLoc,

clang/lib/AST/Stmt.cpp

@@ -1192,6 +1192,30 @@ OMPSharedClause *OMPSharedClause::CreateEmpty(const ASTContext &C,
   return new (Mem) OMPSharedClause(N);
 }
 
+OMPLinearClause *OMPLinearClause::Create(const ASTContext &C,
+                                         SourceLocation StartLoc,
+                                         SourceLocation LParenLoc,
+                                         SourceLocation ColonLoc,
+                                         SourceLocation EndLoc,
+                                         ArrayRef<Expr *> VL, Expr *Step) {
+  void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPLinearClause),
+                                                  llvm::alignOf<Expr *>()) +
+                         sizeof(Expr *) * (VL.size() + 1));
+  OMPLinearClause *Clause = new (Mem)
+      OMPLinearClause(StartLoc, LParenLoc, ColonLoc, EndLoc, VL.size());
+  Clause->setVarRefs(VL);
+  Clause->setStep(Step);
+  return Clause;
+}
+
+OMPLinearClause *OMPLinearClause::CreateEmpty(const ASTContext &C,
+                                              unsigned NumVars) {
+  void *Mem = C.Allocate(llvm::RoundUpToAlignment(sizeof(OMPLinearClause),
+                                                  llvm::alignOf<Expr *>()) +
+                         sizeof(Expr *) * (NumVars + 1));
+  return new (Mem) OMPLinearClause(NumVars);
+}
+
 OMPCopyinClause *OMPCopyinClause::Create(const ASTContext &C,
                                          SourceLocation StartLoc,
                                          SourceLocation LParenLoc,

clang/lib/AST/StmtPrinter.cpp

@@ -664,6 +664,18 @@ void OMPClausePrinter::VisitOMPSharedClause(OMPSharedClause *Node) {
   }
 }
 
+void OMPClausePrinter::VisitOMPLinearClause(OMPLinearClause *Node) {
+  if (!Node->varlist_empty()) {
+    OS << "linear";
+    VisitOMPClauseList(Node, '(');
+    if (Node->getStep() != 0) {
+      OS << ": ";
+      Node->getStep()->printPretty(OS, 0, Policy, 0);
+    }
+    OS << ")";
+  }
+}
+
 void OMPClausePrinter::VisitOMPCopyinClause(OMPCopyinClause *Node) {
   if (!Node->varlist_empty()) {
     OS << "copyin";

clang/lib/AST/StmtProfile.cpp

@@ -297,6 +297,10 @@ void OMPClauseProfiler::VisitOMPFirstprivateClause(
 void OMPClauseProfiler::VisitOMPSharedClause(const OMPSharedClause *C) {
   VisitOMPClauseList(C);
 }
+void OMPClauseProfiler::VisitOMPLinearClause(const OMPLinearClause *C) {
+  VisitOMPClauseList(C);
+  Profiler->VisitStmt(C->getStep());
+}
 void OMPClauseProfiler::VisitOMPCopyinClause(const OMPCopyinClause *C) {
   VisitOMPClauseList(C);
 }

clang/lib/Basic/OpenMPKinds.cpp

@@ -83,6 +83,7 @@ unsigned clang::getOpenMPSimpleClauseType(OpenMPClauseKind Kind,
   case OMPC_private:
   case OMPC_firstprivate:
   case OMPC_shared:
+  case OMPC_linear:
   case OMPC_copyin:
   case NUM_OPENMP_CLAUSES:
     break;
@@ -110,6 +111,7 @@ const char *clang::getOpenMPSimpleClauseTypeName(OpenMPClauseKind Kind,
   case OMPC_private:
   case OMPC_firstprivate:
   case OMPC_shared:
+  case OMPC_linear:
   case OMPC_copyin:
   case NUM_OPENMP_CLAUSES:
     break;

clang/lib/Parse/ParseOpenMP.cpp

@@ -258,7 +258,7 @@ bool Parser::ParseOpenMPSimpleVarList(OpenMPDirectiveKind Kind,
 ///
 ///    clause:
 ///       if-clause | num_threads-clause | safelen-clause | default-clause |
-///       private-clause | firstprivate-clause | shared-clause
+///       private-clause | firstprivate-clause | shared-clause | linear-clause
 ///
 OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
                                      OpenMPClauseKind CKind, bool FirstClause) {
@@ -301,6 +301,7 @@ OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
   case OMPC_private:
   case OMPC_firstprivate:
   case OMPC_shared:
+  case OMPC_linear:
   case OMPC_copyin:
     Clause = ParseOpenMPVarListClause(CKind);
     break;
@@ -392,10 +393,13 @@ OMPClause *Parser::ParseOpenMPSimpleClause(OpenMPClauseKind Kind) {
 ///       'firstprivate' '(' list ')'
 ///    shared-clause:
 ///       'shared' '(' list ')'
+///    linear-clause:
+///       'linear' '(' list [ ':' linear-step ] ')'
 ///
 OMPClause *Parser::ParseOpenMPVarListClause(OpenMPClauseKind Kind) {
   SourceLocation Loc = Tok.getLocation();
   SourceLocation LOpen = ConsumeToken();
+  SourceLocation ColonLoc = SourceLocation();
   // Parse '('.
   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
   if (T.expectAndConsume(diag::err_expected_lparen_after,
@@ -404,8 +408,10 @@ OMPClause *Parser::ParseOpenMPVarListClause(OpenMPClauseKind Kind) {
 
   SmallVector<Expr *, 5> Vars;
   bool IsComma = true;
-  while (IsComma || (Tok.isNot(tok::r_paren) &&
+  const bool MayHaveTail = (Kind == OMPC_linear);
+  while (IsComma || (Tok.isNot(tok::r_paren) && Tok.isNot(tok::colon) &&
                      Tok.isNot(tok::annot_pragma_openmp_end))) {
+    ColonProtectionRAIIObject ColonRAII(*this, MayHaveTail);
     // Parse variable
     ExprResult VarExpr = ParseAssignmentExpression();
     if (VarExpr.isUsable()) {
@@ -416,21 +422,34 @@ OMPClause *Parser::ParseOpenMPVarListClause(OpenMPClauseKind Kind) {
     }
     // Skip ',' if any
     IsComma = Tok.is(tok::comma);
-    if (IsComma) {
+    if (IsComma)
       ConsumeToken();
-    } else if (Tok.isNot(tok::r_paren) &&
-               Tok.isNot(tok::annot_pragma_openmp_end)) {
-      Diag(Tok, diag::err_omp_expected_punc)
-        << getOpenMPClauseName(Kind);
-    }
+    else if (Tok.isNot(tok::r_paren) &&
+             Tok.isNot(tok::annot_pragma_openmp_end) &&
+             (!MayHaveTail || Tok.isNot(tok::colon)))
+      Diag(Tok, diag::err_omp_expected_punc) << getOpenMPClauseName(Kind);
+  }
+
+  // Parse ':' linear-step
+  Expr *TailExpr = 0;
+  const bool MustHaveTail = MayHaveTail && Tok.is(tok::colon);
+  if (MustHaveTail) {
+    ColonLoc = Tok.getLocation();
+    ConsumeToken();
+    ExprResult Tail = ParseAssignmentExpression();
+    if (Tail.isUsable())
+      TailExpr = Tail.take();
+    else
+      SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
+                StopBeforeMatch);
   }
 
   // Parse ')'.
   T.consumeClose();
-  if (Vars.empty())
+  if (Vars.empty() || (MustHaveTail && !TailExpr))
     return 0;
 
-  return Actions.ActOnOpenMPVarListClause(Kind, Vars, Loc, LOpen,
-                                          Tok.getLocation());
+  return Actions.ActOnOpenMPVarListClause(Kind, Vars, TailExpr, Loc, LOpen,
+                                          ColonLoc, Tok.getLocation());
 }