[OpenMP] atomic compare fail : Parser & AST support

This is a support for " #pragma omp atomic compare fail ". It has Parser & AST support for now.

Reviewed By: tianshilei1992, ABataev

Differential Revision: https://reviews.llvm.org/D123235

Author: SunilKuravinakop

clang/include/clang/AST/OpenMPClause.h

@@ -2513,6 +2513,104 @@ class OMPRelaxedClause final : public OMPClause {
   }
 };
 
+/// This represents 'fail' clause in the '#pragma omp atomic'
+/// directive.
+///
+/// \code
+/// #pragma omp atomic compare fail
+/// \endcode
+/// In this example directive '#pragma omp atomic compare' has 'fail' clause.
+class OMPFailClause final : public OMPClause {
+
+  // FailParameter is a memory-order-clause. Storing the ClauseKind is
+  // sufficient for our purpose.
+  OpenMPClauseKind FailParameter = llvm::omp::Clause::OMPC_unknown;
+  SourceLocation FailParameterLoc;
+  SourceLocation LParenLoc;
+
+  friend class OMPClauseReader;
+
+  /// Sets the location of '(' in fail clause.
+  void setLParenLoc(SourceLocation Loc) {
+    LParenLoc = Loc;
+  }
+
+  /// Sets the location of memoryOrder clause argument in fail clause.
+  void setFailParameterLoc(SourceLocation Loc) { FailParameterLoc = Loc; }
+
+  /// Sets the mem_order clause for 'atomic compare fail' directive.
+  void setFailParameter(OpenMPClauseKind FailParameter) {
+    switch (FailParameter) {
+    case llvm::omp::OMPC_acq_rel:
+    case llvm::omp::OMPC_acquire:
+      this->FailParameter = llvm::omp::OMPC_acquire;
+      break;
+    case llvm::omp::OMPC_relaxed:
+    case llvm::omp::OMPC_release:
+      this->FailParameter = llvm::omp::OMPC_relaxed;
+      break;
+    case llvm::omp::OMPC_seq_cst:
+      this->FailParameter = llvm::omp::OMPC_seq_cst;
+      break;
+    default:
+      this->FailParameter = llvm::omp::OMPC_unknown;
+      break;
+    }
+  }
+
+public:
+  /// Build 'fail' clause.
+  ///
+  /// \param StartLoc Starting location of the clause.
+  /// \param EndLoc Ending location of the clause.
+  OMPFailClause(SourceLocation StartLoc, SourceLocation EndLoc)
+      : OMPClause(llvm::omp::OMPC_fail, StartLoc, EndLoc) {}
+
+  OMPFailClause(OpenMPClauseKind FailParameter, SourceLocation FailParameterLoc,
+                SourceLocation StartLoc, SourceLocation LParenLoc,
+                SourceLocation EndLoc)
+      : OMPClause(llvm::omp::OMPC_fail, StartLoc, EndLoc),
+        FailParameterLoc(FailParameterLoc), LParenLoc(LParenLoc) {
+
+    setFailParameter(FailParameter);
+  }
+
+  /// Build an empty clause.
+  OMPFailClause()
+      : OMPClause(llvm::omp::OMPC_fail, SourceLocation(), SourceLocation()) {}
+
+  child_range children() {
+    return child_range(child_iterator(), child_iterator());
+  }
+
+  const_child_range children() const {
+    return const_child_range(const_child_iterator(), const_child_iterator());
+  }
+
+  child_range used_children() {
+    return child_range(child_iterator(), child_iterator());
+  }
+  const_child_range used_children() const {
+    return const_child_range(const_child_iterator(), const_child_iterator());
+  }
+
+  static bool classof(const OMPClause *T) {
+    return T->getClauseKind() == llvm::omp::OMPC_fail;
+  }
+
+  /// Gets the location of '(' (for the parameter) in fail clause.
+  SourceLocation getLParenLoc() const {
+    return LParenLoc;
+  }
+
+  /// Gets the location of Fail Parameter (type memory-order-clause) in
+  /// fail clause.
+  SourceLocation getFailParameterLoc() const { return FailParameterLoc; }
+
+  /// Gets the parameter (type memory-order-clause) in Fail clause.
+  OpenMPClauseKind getFailParameter() const { return FailParameter; }
+};
+
 /// This represents clause 'private' in the '#pragma omp ...' directives.
 ///
 /// \code

clang/include/clang/AST/RecursiveASTVisitor.h

@@ -3398,6 +3398,11 @@ bool RecursiveASTVisitor<Derived>::VisitOMPCompareClause(OMPCompareClause *) {
   return true;
 }
 
+template <typename Derived>
+bool RecursiveASTVisitor<Derived>::VisitOMPFailClause(OMPFailClause *) {
+  return true;
+}
+
 template <typename Derived>
 bool RecursiveASTVisitor<Derived>::VisitOMPSeqCstClause(OMPSeqCstClause *) {
   return true;

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -10962,6 +10962,8 @@ def note_omp_atomic_compare: Note<
   "expect binary operator in conditional expression|expect '<', '>' or '==' as order operator|expect comparison in a form of 'x == e', 'e == x', 'x ordop expr', or 'expr ordop x'|"
   "expect lvalue for result value|expect scalar value|expect integer value|unexpected 'else' statement|expect '==' operator|expect an assignment statement 'v = x'|"
   "expect a 'if' statement|expect no more than two statements|expect a compound statement|expect 'else' statement|expect a form 'r = x == e; if (r) ...'}0">;
+def err_omp_atomic_fail_wrong_or_no_clauses : Error<"expected a memory order clause">;
+def err_omp_atomic_fail_no_compare : Error<"expected 'compare' clause with the 'fail' modifier">;
 def err_omp_atomic_several_clauses : Error<
   "directive '#pragma omp atomic' cannot contain more than one 'read', 'write', 'update', 'capture', or 'compare' clause">;
 def err_omp_several_mem_order_clauses : Error<

clang/include/clang/Basic/OpenMPKinds.def

@@ -41,6 +41,9 @@
 #ifndef OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND
 #define OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(Name)
 #endif
+#ifndef OPENMP_ATOMIC_FAIL_MODIFIER
+#define OPENMP_ATOMIC_FAIL_MODIFIER(Name)
+#endif
 #ifndef OPENMP_AT_KIND
 #define OPENMP_AT_KIND(Name)
 #endif
@@ -138,6 +141,13 @@ OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(seq_cst)
 OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(acq_rel)
 OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(relaxed)
 
+// Modifiers for atomic 'fail' clause.
+OPENMP_ATOMIC_FAIL_MODIFIER(seq_cst)
+OPENMP_ATOMIC_FAIL_MODIFIER(acquire)
+OPENMP_ATOMIC_FAIL_MODIFIER(acq_rel)
+OPENMP_ATOMIC_FAIL_MODIFIER(relaxed)
+OPENMP_ATOMIC_FAIL_MODIFIER(release)
+
 // Modifiers for 'at' clause.
 OPENMP_AT_KIND(compilation)
 OPENMP_AT_KIND(execution)
@@ -226,6 +236,7 @@ OPENMP_DOACROSS_MODIFIER(source_omp_cur_iteration)
 #undef OPENMP_SCHEDULE_MODIFIER
 #undef OPENMP_SCHEDULE_KIND
 #undef OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND
+#undef OPENMP_ATOMIC_FAIL_MODIFIER
 #undef OPENMP_AT_KIND
 #undef OPENMP_SEVERITY_KIND
 #undef OPENMP_MAP_KIND

clang/include/clang/Sema/Sema.h

@@ -12186,6 +12186,13 @@ class Sema final {
   /// Called on well-formed 'compare' clause.
   OMPClause *ActOnOpenMPCompareClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
+  /// Called on well-formed 'fail' clause.
+  OMPClause *ActOnOpenMPFailClause(SourceLocation StartLoc,
+                                   SourceLocation EndLoc);
+  OMPClause *ActOnOpenMPFailClause(
+      OpenMPClauseKind Kind, SourceLocation KindLoc,
+      SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation EndLoc);
+
   /// Called on well-formed 'seq_cst' clause.
   OMPClause *ActOnOpenMPSeqCstClause(SourceLocation StartLoc,
                                      SourceLocation EndLoc);

clang/lib/AST/OpenMPClause.cpp

@@ -130,6 +130,7 @@ const OMPClauseWithPreInit *OMPClauseWithPreInit::get(const OMPClause *C) {
   case OMPC_update:
   case OMPC_capture:
   case OMPC_compare:
+  case OMPC_fail:
   case OMPC_seq_cst:
   case OMPC_acq_rel:
   case OMPC_acquire:
@@ -227,6 +228,7 @@ const OMPClauseWithPostUpdate *OMPClauseWithPostUpdate::get(const OMPClause *C)
   case OMPC_update:
   case OMPC_capture:
   case OMPC_compare:
+  case OMPC_fail:
   case OMPC_seq_cst:
   case OMPC_acq_rel:
   case OMPC_acquire:
@@ -1925,6 +1927,16 @@ void OMPClausePrinter::VisitOMPCompareClause(OMPCompareClause *) {
   OS << "compare";
 }
 
+void OMPClausePrinter::VisitOMPFailClause(OMPFailClause *Node) {
+  OS << "fail";
+  if (Node) {
+    OS << "(";
+    OS << getOpenMPSimpleClauseTypeName(
+        Node->getClauseKind(), static_cast<int>(Node->getFailParameter()));
+    OS << ")";
+  }
+}
+
 void OMPClausePrinter::VisitOMPSeqCstClause(OMPSeqCstClause *) {
   OS << "seq_cst";
 }

clang/lib/AST/StmtProfile.cpp

@@ -582,6 +582,8 @@ void OMPClauseProfiler::VisitOMPCaptureClause(const OMPCaptureClause *) {}
 
 void OMPClauseProfiler::VisitOMPCompareClause(const OMPCompareClause *) {}
 
+void OMPClauseProfiler::VisitOMPFailClause(const OMPFailClause *) {}
+
 void OMPClauseProfiler::VisitOMPSeqCstClause(const OMPSeqCstClause *) {}
 
 void OMPClauseProfiler::VisitOMPAcqRelClause(const OMPAcqRelClause *) {}

clang/lib/Basic/OpenMPKinds.cpp

@@ -104,6 +104,11 @@ unsigned clang::getOpenMPSimpleClauseType(OpenMPClauseKind Kind, StringRef Str,
   .Case(#Name, OMPC_ATOMIC_DEFAULT_MEM_ORDER_##Name)
 #include "clang/Basic/OpenMPKinds.def"
         .Default(OMPC_ATOMIC_DEFAULT_MEM_ORDER_unknown);
+  case OMPC_fail:
+    return static_cast<unsigned int>(llvm::StringSwitch<llvm::omp::Clause>(Str)
+#define OPENMP_ATOMIC_FAIL_MODIFIER(Name) .Case(#Name, OMPC_##Name)
+#include "clang/Basic/OpenMPKinds.def"
+                                         .Default(OMPC_unknown));
   case OMPC_device_type:
     return llvm::StringSwitch<OpenMPDeviceType>(Str)
 #define OPENMP_DEVICE_TYPE_KIND(Name) .Case(#Name, OMPC_DEVICE_TYPE_##Name)
@@ -434,6 +439,18 @@ const char *clang::getOpenMPSimpleClauseTypeName(OpenMPClauseKind Kind,
 #include "clang/Basic/OpenMPKinds.def"
     }
     llvm_unreachable("Invalid OpenMP 'depend' clause type");
+  case OMPC_fail: {
+    OpenMPClauseKind CK = static_cast<OpenMPClauseKind>(Type);
+    switch (CK) {
+    case OMPC_unknown:
+      return "unknown";
+#define OPENMP_ATOMIC_FAIL_MODIFIER(Name)                                      \
+  case OMPC_##Name:                                                            \
+    return #Name;
+#include "clang/Basic/OpenMPKinds.def"
+    }
+    llvm_unreachable("Invalid OpenMP 'fail' clause modifier");
+  }
   case OMPC_device:
     switch (Type) {
     case OMPC_DEVICE_unknown:

clang/lib/CodeGen/CGStmtOpenMP.cpp

@@ -6516,6 +6516,10 @@ static void emitOMPAtomicExpr(CodeGenFunction &CGF, OpenMPClauseKind Kind,
                              IsPostfixUpdate, IsFailOnly, Loc);
     break;
   }
+  case OMPC_fail: {
+    //TODO
+    break;
+  }
   default:
     llvm_unreachable("Clause is not allowed in 'omp atomic'.");
   }

clang/lib/Parse/ParseOpenMP.cpp

@@ -3248,6 +3248,7 @@ OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
     else
       Clause = ParseOpenMPSingleExprClause(CKind, WrongDirective);
     break;
+  case OMPC_fail:
   case OMPC_default:
   case OMPC_proc_bind:
   case OMPC_atomic_default_mem_order:

clang/lib/Sema/SemaOpenMP.cpp

@@ -12682,6 +12682,23 @@ StmtResult Sema::ActOnOpenMPAtomicDirective(ArrayRef<OMPClause *> Clauses,
       }
       break;
     }
+    case OMPC_fail: {
+      if (AtomicKind != OMPC_compare) {
+        Diag(C->getBeginLoc(), diag::err_omp_atomic_fail_no_compare)
+            << SourceRange(C->getBeginLoc(), C->getEndLoc());
+        return StmtError();
+      }
+      const auto *FC = cast<OMPFailClause>(C);
+      OpenMPClauseKind FailParameter = FC->getFailParameter();
+      SourceLocation DisplayLocation = FailParameter == OMPC_unknown
+                                           ? FC->getBeginLoc()
+                                           : FC->getFailParameterLoc();
+      if (FailParameter != OMPC_acq_rel && FailParameter != OMPC_acquire &&
+          FailParameter != OMPC_relaxed && FailParameter != OMPC_release &&
+          FailParameter != OMPC_seq_cst)
+        Diag(DisplayLocation, diag::err_omp_atomic_fail_wrong_or_no_clauses);
+      break;
+    }
     case OMPC_seq_cst:
     case OMPC_acq_rel:
     case OMPC_acquire:
@@ -16883,6 +16900,11 @@ OMPClause *Sema::ActOnOpenMPSimpleClause(
         static_cast<OpenMPAtomicDefaultMemOrderClauseKind>(Argument),
         ArgumentLoc, StartLoc, LParenLoc, EndLoc);
     break;
+  case OMPC_fail:
+    Res = ActOnOpenMPFailClause(
+        static_cast<OpenMPClauseKind>(Argument),
+        ArgumentLoc, StartLoc, LParenLoc, EndLoc);
+    break;
   case OMPC_update:
     Res = ActOnOpenMPUpdateClause(static_cast<OpenMPDependClauseKind>(Argument),
                                   ArgumentLoc, StartLoc, LParenLoc, EndLoc);
@@ -17523,6 +17545,9 @@ OMPClause *Sema::ActOnOpenMPClause(OpenMPClauseKind Kind,
   case OMPC_compare:
     Res = ActOnOpenMPCompareClause(StartLoc, EndLoc);
     break;
+  case OMPC_fail:
+    Res = ActOnOpenMPFailClause(StartLoc, EndLoc);
+    break;
   case OMPC_seq_cst:
     Res = ActOnOpenMPSeqCstClause(StartLoc, EndLoc);
     break;
@@ -17683,6 +17708,20 @@ OMPClause *Sema::ActOnOpenMPCompareClause(SourceLocation StartLoc,
   return new (Context) OMPCompareClause(StartLoc, EndLoc);
 }
 
+OMPClause *Sema::ActOnOpenMPFailClause(SourceLocation StartLoc,
+                                       SourceLocation EndLoc) {
+  return new (Context) OMPFailClause(StartLoc, EndLoc);
+}
+
+OMPClause *Sema::ActOnOpenMPFailClause(
+      OpenMPClauseKind Parameter, SourceLocation KindLoc,
+      SourceLocation StartLoc, SourceLocation LParenLoc,
+      SourceLocation EndLoc) {
+
+  return new (Context)
+      OMPFailClause(Parameter, KindLoc, StartLoc, LParenLoc, EndLoc);
+}
+
 OMPClause *Sema::ActOnOpenMPSeqCstClause(SourceLocation StartLoc,
                                          SourceLocation EndLoc) {
   return new (Context) OMPSeqCstClause(StartLoc, EndLoc);

clang/lib/Sema/TreeTransform.h

@@ -9866,6 +9866,12 @@ TreeTransform<Derived>::TransformOMPCompareClause(OMPCompareClause *C) {
   return C;
 }
 
+template <typename Derived>
+OMPClause *TreeTransform<Derived>::TransformOMPFailClause(OMPFailClause *C) {
+  // No need to rebuild this clause, no template-dependent parameters.
+  return C;
+}
+
 template <typename Derived>
 OMPClause *
 TreeTransform<Derived>::TransformOMPSeqCstClause(OMPSeqCstClause *C) {

clang/lib/Serialization/ASTReader.cpp

@@ -10274,6 +10274,9 @@ OMPClause *OMPClauseReader::readClause() {
   case llvm::omp::OMPC_compare:
     C = new (Context) OMPCompareClause();
     break;
+  case llvm::omp::OMPC_fail:
+    C = new (Context) OMPFailClause();
+    break;
   case llvm::omp::OMPC_seq_cst:
     C = new (Context) OMPSeqCstClause();
     break;
@@ -10667,6 +10670,16 @@ void OMPClauseReader::VisitOMPCaptureClause(OMPCaptureClause *) {}
 
 void OMPClauseReader::VisitOMPCompareClause(OMPCompareClause *) {}
 
+// Read the parameter of fail clause. This will have been saved when
+// OMPClauseWriter is called.
+void OMPClauseReader::VisitOMPFailClause(OMPFailClause *C) {
+  C->setLParenLoc(Record.readSourceLocation());
+  SourceLocation FailParameterLoc = Record.readSourceLocation();
+  C->setFailParameterLoc(FailParameterLoc);
+  OpenMPClauseKind CKind = Record.readEnum<OpenMPClauseKind>();
+  C->setFailParameter(CKind);
+}
+
 void OMPClauseReader::VisitOMPSeqCstClause(OMPSeqCstClause *) {}
 
 void OMPClauseReader::VisitOMPAcqRelClause(OMPAcqRelClause *) {}

clang/lib/Serialization/ASTWriter.cpp

@@ -6620,6 +6620,13 @@ void OMPClauseWriter::VisitOMPCaptureClause(OMPCaptureClause *) {}
 
 void OMPClauseWriter::VisitOMPCompareClause(OMPCompareClause *) {}
 
+// Save the parameter of fail clause.
+void OMPClauseWriter::VisitOMPFailClause(OMPFailClause *C) {
+  Record.AddSourceLocation(C->getLParenLoc());
+  Record.AddSourceLocation(C->getFailParameterLoc());
+  Record.writeEnum(C->getFailParameter());
+}
+
 void OMPClauseWriter::VisitOMPSeqCstClause(OMPSeqCstClause *) {}
 
 void OMPClauseWriter::VisitOMPAcqRelClause(OMPAcqRelClause *) {}