[Flang][OpenMP][Sema] Adding parsing and semantic support for scan directive.

flang/include/flang/Semantics/openmp-directive-sets.h

@@ -290,6 +290,12 @@ static const OmpDirectiveSet workShareSet{
     } | allDoSet,
 };
 
+//===----------------------------------------------------------------------===//
+// Directive sets for parent directives that do allow/not allow a construct
+//===----------------------------------------------------------------------===//
+
+static const OmpDirectiveSet scanParentAllowedSet{allDoSet | allSimdSet};
+
 //===----------------------------------------------------------------------===//
 // Directive sets for allowed/not allowed nested directives
 //===----------------------------------------------------------------------===//

flang/include/flang/Semantics/symbol.h

@@ -755,7 +755,7 @@ class Symbol {
       OmpDeclarativeAllocateDirective, OmpExecutableAllocateDirective,
       OmpDeclareSimd, OmpDeclareTarget, OmpThreadprivate, OmpDeclareReduction,
       OmpFlushed, OmpCriticalLock, OmpIfSpecified, OmpNone, OmpPreDetermined,
-      OmpImplicit, OmpDependObject);
+      OmpImplicit, OmpDependObject, OmpInclusiveScan, OmpExclusiveScan);
   using Flags = common::EnumSet<Flag, Flag_enumSize>;
 
   const Scope &owner() const { return *owner_; }

flang/lib/Lower/OpenMP/OpenMP.cpp

@@ -2520,6 +2520,9 @@ static void genOMPDispatch(lower::AbstractConverter &converter,
   case llvm::omp::Directive::OMPD_parallel:
     genStandaloneParallel(converter, symTable, semaCtx, eval, loc, queue, item);
     break;
+  case llvm::omp::Directive::OMPD_scan:
+    TODO(loc, "Unhandled directive " + llvm::omp::getOpenMPDirectiveName(dir));
+    break;
   case llvm::omp::Directive::OMPD_section:
     llvm_unreachable("genOMPDispatch: OMPD_section");
     // Lowered in the enclosing genSectionsOp.

flang/lib/Parser/openmp-parsers.cpp

@@ -559,6 +559,8 @@ TYPE_PARSER(
         construct<OmpClause>(construct<OmpClause::DynamicAllocators>()) ||
     "ENTER" >> construct<OmpClause>(construct<OmpClause::Enter>(
                    parenthesized(Parser<OmpObjectList>{}))) ||
+    "EXCLUSIVE" >> construct<OmpClause>(construct<OmpClause::Exclusive>(
+                       parenthesized(Parser<OmpObjectList>{}))) ||
     "FILTER" >> construct<OmpClause>(construct<OmpClause::Filter>(
                     parenthesized(scalarIntExpr))) ||
     "FINAL" >> construct<OmpClause>(construct<OmpClause::Final>(
@@ -578,6 +580,8 @@ TYPE_PARSER(
     "IF" >> construct<OmpClause>(construct<OmpClause::If>(
                 parenthesized(Parser<OmpIfClause>{}))) ||
     "INBRANCH" >> construct<OmpClause>(construct<OmpClause::Inbranch>()) ||
+    "INCLUSIVE" >> construct<OmpClause>(construct<OmpClause::Inclusive>(
+                       parenthesized(Parser<OmpObjectList>{}))) ||
     "IS_DEVICE_PTR" >> construct<OmpClause>(construct<OmpClause::IsDevicePtr>(
                            parenthesized(Parser<OmpObjectList>{}))) ||
     "LASTPRIVATE" >> construct<OmpClause>(construct<OmpClause::Lastprivate>(
@@ -790,6 +794,7 @@ TYPE_PARSER(sourced(construct<OpenMPFlushConstruct>(verbatim("FLUSH"_tok),
 TYPE_PARSER(sourced(construct<OmpSimpleStandaloneDirective>(first(
     "BARRIER" >> pure(llvm::omp::Directive::OMPD_barrier),
     "ORDERED" >> pure(llvm::omp::Directive::OMPD_ordered),
+    "SCAN" >> pure(llvm::omp::Directive::OMPD_scan),
     "TARGET ENTER DATA" >> pure(llvm::omp::Directive::OMPD_target_enter_data),
     "TARGET EXIT DATA" >> pure(llvm::omp::Directive::OMPD_target_exit_data),
     "TARGET UPDATE" >> pure(llvm::omp::Directive::OMPD_target_update),

flang/lib/Parser/unparse.cpp

@@ -2393,6 +2393,9 @@ class UnparseVisitor {
     case llvm::omp::Directive::OMPD_barrier:
       Word("BARRIER ");
       break;
+    case llvm::omp::Directive::OMPD_scan:
+      Word("SCAN ");
+      break;
     case llvm::omp::Directive::OMPD_taskwait:
       Word("TASKWAIT ");
       break;