[llvm-branch-commits] [flang] [flang][OpenM] Check if loop nest/sequence is well-formed (PR #188025)

[Jack Styles via llvm-branch-commits]

================
@@ -268,93 +258,83 @@ void OmpStructureChecker::CheckNestedConstruct(
 
   // Check constructs contained in the body of the loop construct.
   auto &body{std::get<parser::Block>(x.t)};
+
   for (auto &stmt : BlockRange(body, BlockRange::Step::Over)) {
     if (auto *d{parser::Unwrap<parser::CompilerDirective>(stmt)}) {
       context_.Say(d->source,
           "Compiler directives are not allowed inside OpenMP loop constructs"_warn_en_US);
-    } else if (auto *omp{parser::Unwrap<parser::OpenMPLoopConstruct>(stmt)}) {
-      if (!IsLoopTransforming(omp->BeginDir().DirId())) {
-        context_.Say(omp->source,
-            "Only loop-transforming OpenMP constructs are allowed inside OpenMP loop constructs"_err_en_US);
-      }
-      if (IsFullUnroll(*omp)) {
-        context_.Say(x.source,
-            "OpenMP loop construct cannot apply to a fully unrolled loop"_err_en_US);
-      }
-    } else if (!parser::Unwrap<parser::DoConstruct>(stmt)) {
-      parser::CharBlock source{parser::GetSource(stmt).value_or(x.source)};
-      context_.Say(source,
-          "OpenMP loop construct can only contain DO loops or loop-nest-generating OpenMP constructs"_err_en_US);
     }
   }
 
   LoopSequence sequence(body, version, true);
 
-  // Check if a loop-nest-associated construct has only one top-level loop
-  // in it.
+  auto assoc{llvm::omp::getDirectiveAssociation(dir)};
   auto needRange{GetAffectedLoopRangeWithReason(beginSpec, version)};
+  auto haveLength{sequence.length()};
 
-  if (auto haveLength{sequence.length()}) {
-    if (*haveLength.value == 0) {
+  if (assoc == llvm::omp::Association::LoopNest) {
----------------
Stylie777 wrote:

Is there a risk here that things may be missed if we are now checking only for loop nest associated directives? 

https://github.com/llvm/llvm-project/pull/188025