[flang][OpenMP] Fix scope checks for ALLOCATE directive (llvm#160948)

Make sure that the ALLOCATE directive adds its source span to the
current scope, and that the scope checks compare scoping units, not the
specific scopes.

Author: kparzysz

flang/lib/Semantics/resolve-directives.cpp

@@ -362,6 +362,24 @@ class OmpAttributeVisitor : DirectiveAttributeVisitor<llvm::omp::Directive> {
   explicit OmpAttributeVisitor(SemanticsContext &context)
       : DirectiveAttributeVisitor(context) {}
 
+  static const Scope &scopingUnit(const Scope &scope) {
+    const Scope *iter{&scope};
+    for (; !iter->IsTopLevel(); iter = &iter->parent()) {
+      switch (iter->kind()) {
+      case Scope::Kind::BlockConstruct:
+      case Scope::Kind::BlockData:
+      case Scope::Kind::DerivedType:
+      case Scope::Kind::MainProgram:
+      case Scope::Kind::Module:
+      case Scope::Kind::Subprogram:
+        return *iter;
+      default:
+        break;
+      }
+    }
+    return *iter;
+  }
+
   template <typename A> void Walk(const A &x) { parser::Walk(x, *this); }
   template <typename A> bool Pre(const A &) { return true; }
   template <typename A> void Post(const A &) {}
@@ -952,7 +970,6 @@ class OmpAttributeVisitor : DirectiveAttributeVisitor<llvm::omp::Directive> {
   void ResolveOmpNameList(const std::list<parser::Name> &, Symbol::Flag);
   void ResolveOmpName(const parser::Name &, Symbol::Flag);
   Symbol *ResolveName(const parser::Name *);
-  Symbol *ResolveOmpObjectScope(const parser::Name *);
   Symbol *DeclareOrMarkOtherAccessEntity(const parser::Name &, Symbol::Flag);
   Symbol *DeclareOrMarkOtherAccessEntity(Symbol &, Symbol::Flag);
   void CheckMultipleAppearances(
@@ -2920,31 +2937,6 @@ Symbol *OmpAttributeVisitor::ResolveOmpCommonBlockName(
   return nullptr;
 }
 
-// Use this function over ResolveOmpName when an omp object's scope needs
-// resolving, it's symbol flag isn't important and a simple check for resolution
-// failure is desired. Using ResolveOmpName means needing to work with the
-// context to check for failure, whereas here a pointer comparison is all that's
-// needed.
-Symbol *OmpAttributeVisitor::ResolveOmpObjectScope(const parser::Name *name) {
-
-  // TODO: Investigate whether the following block can be replaced by, or
-  // included in, the ResolveOmpName function
-  if (auto *prev{name ? GetContext().scope.parent().FindSymbol(name->source)
-                      : nullptr}) {
-    name->symbol = prev;
-    return nullptr;
-  }
-
-  // TODO: Investigate whether the following block can be replaced by, or
-  // included in, the ResolveOmpName function
-  if (auto *ompSymbol{
-          name ? GetContext().scope.FindSymbol(name->source) : nullptr}) {
-    name->symbol = ompSymbol;
-    return ompSymbol;
-  }
-  return nullptr;
-}
-
 void OmpAttributeVisitor::ResolveOmpObjectList(
     const parser::OmpObjectList &ompObjectList, Symbol::Flag ompFlag) {
   for (const auto &ompObject : ompObjectList.v) {
@@ -3023,13 +3015,19 @@ void OmpAttributeVisitor::ResolveOmpDesignator(
       context_.Say(designator.source,
           "List items specified in the ALLOCATE directive must not have the ALLOCATABLE attribute unless the directive is associated with an ALLOCATE statement"_err_en_US);
     }
-    if ((ompFlag == Symbol::Flag::OmpDeclarativeAllocateDirective ||
-            ompFlag == Symbol::Flag::OmpExecutableAllocateDirective) &&
-        ResolveOmpObjectScope(name) == nullptr) {
-      context_.Say(designator.source, // 2.15.3
-          "List items must be declared in the same scoping unit in which the %s directive appears"_err_en_US,
-          parser::ToUpperCaseLetters(
-              llvm::omp::getOpenMPDirectiveName(directive, version)));
+    bool checkScope{ompFlag == Symbol::Flag::OmpDeclarativeAllocateDirective};
+    // In 5.1 the scope check only applies to declarative allocate.
+    if (version == 50 && !checkScope) {
+      checkScope = ompFlag == Symbol::Flag::OmpExecutableAllocateDirective;
+    }
+    if (checkScope) {
+      if (scopingUnit(GetContext().scope) !=
+          scopingUnit(symbol->GetUltimate().owner())) {
+        context_.Say(designator.source, // 2.15.3
+            "List items must be declared in the same scoping unit in which the %s directive appears"_err_en_US,
+            parser::ToUpperCaseLetters(
+                llvm::omp::getOpenMPDirectiveName(directive, version)));
+      }
     }
     if (ompFlag == Symbol::Flag::OmpReduction) {
       // Using variables inside of a namelist in OpenMP reductions

flang/lib/Semantics/resolve-names.cpp

@@ -1618,12 +1618,14 @@ class OmpVisitor : public virtual DeclarationVisitor {
   void Post(const parser::OpenMPDeclareTargetConstruct &) {
     SkipImplicitTyping(false);
   }
-  bool Pre(const parser::OpenMPDeclarativeAllocate &) {
+  bool Pre(const parser::OpenMPDeclarativeAllocate &x) {
+    AddOmpSourceRange(x.source);
     SkipImplicitTyping(true);
     return true;
   }
   void Post(const parser::OpenMPDeclarativeAllocate &) {
     SkipImplicitTyping(false);
+    messageHandler().set_currStmtSource(std::nullopt);
   }
   bool Pre(const parser::OpenMPDeclarativeConstruct &x) {
     AddOmpSourceRange(x.source);

flang/test/Semantics/OpenMP/allocate01.f90

@@ -20,7 +20,6 @@ subroutine sema()
         print *, a
 
     !WARNING: OpenMP directive ALLOCATE has been deprecated, please use ALLOCATORS instead. [-Wopen-mp-usage]
-    !ERROR: List items must be declared in the same scoping unit in which the ALLOCATE directive appears
     !$omp allocate(x) allocator(omp_default_mem_alloc)
       allocate ( x(a), darray(a, b) )
     end subroutine sema

flang/test/Semantics/OpenMP/allocate08.f90

@@ -27,10 +27,12 @@ subroutine allocate()
 
   !$omp allocate(x) allocator(omp_default_mem_alloc)
   !$omp allocate(y) allocator(omp_default_mem_alloc)
+  !ERROR: List items must be declared in the same scoping unit in which the ALLOCATE directive appears
   !$omp allocate(z) allocator(omp_default_mem_alloc)
 
   !$omp allocate(x)
   !$omp allocate(y)
+  !ERROR: List items must be declared in the same scoping unit in which the ALLOCATE directive appears
   !$omp allocate(z)
 
   !$omp allocate(w) allocator(custom_allocator)
@@ -40,5 +42,6 @@ subroutine allocate()
   !ERROR: If list items within the ALLOCATE directive have the SAVE attribute, are a common block name, or are declared in the scope of a module, then only predefined memory allocator parameters can be used in the allocator clause
   !$omp allocate(y) allocator(custom_allocator)
   !ERROR: If list items within the ALLOCATE directive have the SAVE attribute, are a common block name, or are declared in the scope of a module, then only predefined memory allocator parameters can be used in the allocator clause
+  !ERROR: List items must be declared in the same scoping unit in which the ALLOCATE directive appears
   !$omp allocate(z) allocator(custom_allocator)
 end subroutine allocate

flang/test/Semantics/OpenMP/allocators04.f90

@@ -22,10 +22,12 @@ subroutine allocate()
     trait(1)%value = default_mem_fb
     custom_allocator = omp_init_allocator(omp_default_mem_space, 1, trait)
 
+    !ERROR: List items must be declared in the same scoping unit in which the ALLOCATORS directive appears
     !$omp allocators allocate(omp_default_mem_alloc: a)
         allocate(a)
 
     !ERROR: If list items within the ALLOCATORS directive have the SAVE attribute, are a common block name, or are declared in the scope of a module, then only predefined memory allocator parameters can be used in the allocator clause
+    !ERROR: List items must be declared in the same scoping unit in which the ALLOCATORS directive appears
     !$omp allocators allocate(custom_allocator: b)
         allocate(b)
 end subroutine

flang/test/Semantics/OpenMP/allocators05.f90

@@ -15,11 +15,9 @@ subroutine allocate()
     integer, parameter :: LEN = 2
 
     !$omp target private(a, b)
-    !ERROR: List items must be declared in the same scoping unit in which the ALLOCATORS directive appears
     !$omp allocators allocate(omp_default_mem_alloc: a)
         allocate(a(LEN))
     !ERROR: ALLOCATORS directives that appear in a TARGET region must specify an allocator
-    !ERROR: List items must be declared in the same scoping unit in which the ALLOCATORS directive appears
     !$omp allocators allocate(b)
         allocate(b(LEN))
     !$omp end target