[OpenMP] Add definitions of TASKGRAPH, GRAPH_ID and GRAPH_RESET (#157502)

This only adds the definitions of the TASKGRAPH directive and the
associated clauses, plus the minimal additional changes to make
everything compile without errors.

Author: kparzysz

flang/include/flang/Lower/OpenMP/Clauses.h

@@ -229,6 +229,8 @@ using Firstprivate = tomp::clause::FirstprivateT<TypeTy, IdTy, ExprTy>;
 using From = tomp::clause::FromT<TypeTy, IdTy, ExprTy>;
 using Full = tomp::clause::FullT<TypeTy, IdTy, ExprTy>;
 using Grainsize = tomp::clause::GrainsizeT<TypeTy, IdTy, ExprTy>;
+using GraphId = tomp::clause::GraphIdT<TypeTy, IdTy, ExprTy>;
+using GraphReset = tomp::clause::GraphResetT<TypeTy, IdTy, ExprTy>;
 using HasDeviceAddr = tomp::clause::HasDeviceAddrT<TypeTy, IdTy, ExprTy>;
 using Hint = tomp::clause::HintT<TypeTy, IdTy, ExprTy>;
 using Holds = tomp::clause::HoldsT<TypeTy, IdTy, ExprTy>;

flang/lib/Lower/OpenMP/Clauses.cpp

@@ -221,6 +221,8 @@ MAKE_EMPTY_CLASS(Capture, Capture);
 MAKE_EMPTY_CLASS(Compare, Compare);
 MAKE_EMPTY_CLASS(DynamicAllocators, DynamicAllocators);
 MAKE_EMPTY_CLASS(Full, Full);
+MAKE_EMPTY_CLASS(GraphId, GraphId);
+MAKE_EMPTY_CLASS(GraphReset, GraphReset);
 MAKE_EMPTY_CLASS(Inbranch, Inbranch);
 MAKE_EMPTY_CLASS(Mergeable, Mergeable);
 MAKE_EMPTY_CLASS(Nogroup, Nogroup);

flang/lib/Semantics/check-omp-structure.cpp

@@ -2793,6 +2793,8 @@ CHECK_SIMPLE_CLAUSE(Final, OMPC_final)
 CHECK_SIMPLE_CLAUSE(Flush, OMPC_flush)
 CHECK_SIMPLE_CLAUSE(Full, OMPC_full)
 CHECK_SIMPLE_CLAUSE(Grainsize, OMPC_grainsize)
+CHECK_SIMPLE_CLAUSE(GraphId, OMPC_graph_id)
+CHECK_SIMPLE_CLAUSE(GraphReset, OMPC_graph_reset)
 CHECK_SIMPLE_CLAUSE(Holds, OMPC_holds)
 CHECK_SIMPLE_CLAUSE(Inclusive, OMPC_inclusive)
 CHECK_SIMPLE_CLAUSE(Initializer, OMPC_initializer)

llvm/include/llvm/Frontend/OpenMP/ClauseT.h

@@ -660,6 +660,18 @@ struct GrainsizeT {
   std::tuple<OPT(Prescriptiveness), GrainSize> t;
 };
 
+// [6.0:438] `graph_id` clause
+template <typename T, typename I, typename E> //
+struct GraphIdT {
+  using EmptyTrait = std::true_type;
+};
+
+// [6.0:438] `graph_reset` clause
+template <typename T, typename I, typename E> //
+struct GraphResetT {
+  using EmptyTrait = std::true_type;
+};
+
 // V5.2: [5.4.9] `has_device_addr` clause
 template <typename T, typename I, typename E> //
 struct HasDeviceAddrT {
@@ -1254,10 +1266,11 @@ using ExtensionClausesT =
 template <typename T, typename I, typename E>
 using EmptyClausesT = std::variant<
     AcqRelT<T, I, E>, AcquireT<T, I, E>, CaptureT<T, I, E>, CompareT<T, I, E>,
-    DynamicAllocatorsT<T, I, E>, FullT<T, I, E>, InbranchT<T, I, E>,
-    MergeableT<T, I, E>, NogroupT<T, I, E>, NoOpenmpRoutinesT<T, I, E>,
-    NoOpenmpT<T, I, E>, NoParallelismT<T, I, E>, NotinbranchT<T, I, E>,
-    NowaitT<T, I, E>, ReadT<T, I, E>, RelaxedT<T, I, E>, ReleaseT<T, I, E>,
+    DynamicAllocatorsT<T, I, E>, FullT<T, I, E>, GraphIdT<T, I, E>,
+    GraphResetT<T, I, E>, InbranchT<T, I, E>, MergeableT<T, I, E>,
+    NogroupT<T, I, E>, NoOpenmpRoutinesT<T, I, E>, NoOpenmpT<T, I, E>,
+    NoParallelismT<T, I, E>, NotinbranchT<T, I, E>, NowaitT<T, I, E>,
+    ReadT<T, I, E>, RelaxedT<T, I, E>, ReleaseT<T, I, E>,
     ReverseOffloadT<T, I, E>, SeqCstT<T, I, E>, SimdT<T, I, E>,
     ThreadsT<T, I, E>, UnifiedAddressT<T, I, E>, UnifiedSharedMemoryT<T, I, E>,
     UnknownT<T, I, E>, UntiedT<T, I, E>, UseT<T, I, E>, WeakT<T, I, E>,

llvm/include/llvm/Frontend/OpenMP/OMP.td

@@ -226,6 +226,10 @@ def OMPC_GrainSize : Clause<[Spelling<"grainsize">]> {
     OMP_GRAINSIZE_Unknown
   ];
 }
+def OMPC_GraphId : Clause<[Spelling<"graph_id">]> {
+}
+def OMPC_GraphReset : Clause<[Spelling<"graph_reset">]> {
+}
 def OMPC_HasDeviceAddr : Clause<[Spelling<"has_device_addr">]> {
   let clangClass = "OMPHasDeviceAddrClause";
   let flangClass = "OmpObjectList";
@@ -1210,6 +1214,16 @@ def OMP_Task : Directive<[Spelling<"task">]> {
   let association = AS_Block;
   let category = CA_Executable;
 }
+def OMP_Taskgraph : Directive<[Spelling<"taskgraph">]> {
+  let allowedOnceClauses = [
+    VersionedClause<OMPC_GraphId, 60>,
+    VersionedClause<OMPC_GraphReset, 60>,
+    VersionedClause<OMPC_If>,
+    VersionedClause<OMPC_NoGroup>,
+  ];
+  let association = AS_Block;
+  let category = CA_Executable;
+}
 def OMP_TaskGroup : Directive<[Spelling<"taskgroup">]> {
   let allowedClauses = [
     VersionedClause<OMPC_Allocate, 50>,