[Frontend][OpenMP] Follow compound construct clause restrictions (#107853)

This patch removes from the list of allowed clauses for a handful of
compound constructs those that are specifically disallowed by the OpenMP
spec. In particular, the following restrictions are followed:
- (regarding combined constructs) If _directive-name-A_ is `target`, the
`copyin` clause must not be specified.
- (regarding composite constructs) If _directive-name-A_ is
`distribute`, the `ordered` clause must not be specified.

These restrictions are listed in the OpenMP Specification version 5.2,
sections 17.4 and 17.5. Since it's a similar case as PR #90754, I'm
adding people involved in that decision as reviewers here.

Author: skatrak

flang/test/Lower/OpenMP/distribute-parallel-do.f90

@@ -36,21 +36,21 @@ subroutine distribute_parallel_do_dist_schedule()
   !$omp end teams
 end subroutine distribute_parallel_do_dist_schedule
 
-! CHECK-LABEL: func.func @_QPdistribute_parallel_do_ordered(
-subroutine distribute_parallel_do_ordered()
+! CHECK-LABEL: func.func @_QPdistribute_parallel_do_schedule(
+subroutine distribute_parallel_do_schedule()
   !$omp teams
 
   ! CHECK:      omp.parallel private({{.*}}) {
   ! CHECK:      omp.distribute {
-  ! CHECK-NEXT: omp.wsloop ordered(1) {
+  ! CHECK-NEXT: omp.wsloop schedule(runtime) {
   ! CHECK-NEXT: omp.loop_nest
-  !$omp distribute parallel do ordered(1)
+  !$omp distribute parallel do schedule(runtime)
   do index_ = 1, 10
   end do
   !$omp end distribute parallel do
 
   !$omp end teams
-end subroutine distribute_parallel_do_ordered
+end subroutine distribute_parallel_do_schedule
 
 ! CHECK-LABEL: func.func @_QPdistribute_parallel_do_private(
 subroutine distribute_parallel_do_private()

flang/test/Semantics/OpenMP/combined-constructs.f90

@@ -100,6 +100,7 @@ program main
   enddo
   !$omp end target parallel do
 
+  !ERROR: COPYIN clause is not allowed on the TARGET PARALLEL DO directive
   !ERROR: Non-THREADPRIVATE object 'a' in COPYIN clause
   !$omp target parallel do copyin(a)
   do i = 1, N

flang/test/Semantics/OpenMP/ordered03.f90

@@ -52,6 +52,7 @@ subroutine sub1()
   end do
   !$omp end target parallel do
 
+  !ERROR: ORDERED clause is not allowed on the TARGET TEAMS DISTRIBUTE PARALLEL DO directive
   !$omp target teams distribute parallel do ordered(1)
   do i = 1, N
     !ERROR: An ORDERED construct with the DEPEND clause must be closely nested in a worksharing-loop (or parallel worksharing-loop) construct with ORDERED clause with a parameter

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

@@ -1192,7 +1192,6 @@ def OMP_DistributeParallelDo : Directive<"distribute parallel do"> {
     VersionedClause<OMPC_If>,
     VersionedClause<OMPC_NumThreads>,
     VersionedClause<OMPC_Order, 50>,
-    VersionedClause<OMPC_Ordered>,
     VersionedClause<OMPC_ProcBind>,
     VersionedClause<OMPC_Schedule>,
   ];
@@ -1293,7 +1292,6 @@ def OMP_DistributeSimd : Directive<"distribute simd"> {
     VersionedClause<OMPC_If, 50>,
     VersionedClause<OMPC_NumThreads>,
     VersionedClause<OMPC_Order, 50>,
-    VersionedClause<OMPC_Ordered>,
     VersionedClause<OMPC_ProcBind>,
     VersionedClause<OMPC_SafeLen>,
     VersionedClause<OMPC_Schedule>,
@@ -1840,7 +1838,6 @@ def OMP_TargetParallel : Directive<"target parallel"> {
 def OMP_TargetParallelDo : Directive<"target parallel do"> {
   let allowedClauses = [
     VersionedClause<OMPC_Allocator>,
-    VersionedClause<OMPC_Copyin>,
     VersionedClause<OMPC_Default>,
     VersionedClause<OMPC_Depend>,
     VersionedClause<OMPC_FirstPrivate>,
@@ -1977,7 +1974,6 @@ def OMP_TargetParallelForSimd : Directive<"target parallel for simd"> {
 def OMP_target_parallel_loop : Directive<"target parallel loop"> {
   let allowedClauses = [
     VersionedClause<OMPC_Allocate>,
-    VersionedClause<OMPC_Copyin>,
     VersionedClause<OMPC_Depend>,
     VersionedClause<OMPC_Device>,
     VersionedClause<OMPC_FirstPrivate>,
@@ -2106,7 +2102,6 @@ def OMP_TargetTeamsDistributeParallelDo :
     Directive<"target teams distribute parallel do"> {
   let allowedClauses = [
     VersionedClause<OMPC_Allocate>,
-    VersionedClause<OMPC_Copyin>,
     VersionedClause<OMPC_Depend>,
     VersionedClause<OMPC_FirstPrivate>,
     VersionedClause<OMPC_HasDeviceAddr, 51>,
@@ -2115,7 +2110,6 @@ def OMP_TargetTeamsDistributeParallelDo :
     VersionedClause<OMPC_LastPrivate>,
     VersionedClause<OMPC_Linear>,
     VersionedClause<OMPC_Map>,
-    VersionedClause<OMPC_Ordered>,
     VersionedClause<OMPC_Private>,
     VersionedClause<OMPC_Reduction>,
     VersionedClause<OMPC_Shared>,
@@ -2143,7 +2137,6 @@ def OMP_TargetTeamsDistributeParallelDoSimd :
   let allowedClauses = [
     VersionedClause<OMPC_Aligned>,
     VersionedClause<OMPC_Allocate>,
-    VersionedClause<OMPC_Copyin>,
     VersionedClause<OMPC_Depend>,
     VersionedClause<OMPC_FirstPrivate>,
     VersionedClause<OMPC_HasDeviceAddr, 51>,
@@ -2153,7 +2146,6 @@ def OMP_TargetTeamsDistributeParallelDoSimd :
     VersionedClause<OMPC_Linear>,
     VersionedClause<OMPC_Map>,
     VersionedClause<OMPC_NonTemporal>,
-    VersionedClause<OMPC_Ordered>,
     VersionedClause<OMPC_Private>,
     VersionedClause<OMPC_Reduction>,
     VersionedClause<OMPC_Shared>,
@@ -2395,7 +2387,6 @@ def OMP_TeamsDistributeParallelDo :
     VersionedClause<OMPC_NumTeams>,
     VersionedClause<OMPC_NumThreads>,
     VersionedClause<OMPC_Order, 50>,
-    VersionedClause<OMPC_Ordered>,
     VersionedClause<OMPC_ProcBind>,
     VersionedClause<OMPC_Schedule>,
     VersionedClause<OMPC_ThreadLimit>,