Revert "[flang] OpenMP allocate directive parse tree fix"

This reverts commit 5faf45a3d24e603cbc8fe4eb45da386653dae5e5.
Once again arcanist stripped the co-author metadata.  I'm going to add it to the revision description and try one last time.

5 files changed, 2 insertions, 144 deletions

diff --git a/flang/lib/Parser/unparse.cpp b/flang/lib/Parser/unparse.cpp
index 3b34c4ec89ce..6916052cf78d 100644
--- a/flang/lib/Parser/unparse.cpp
+++ b/flang/lib/Parser/unparse.cpp
@@ -2325,14 +2325,6 @@ public:
     EndOpenMP();
   }
   void Unparse(const OpenMPExecutableAllocate &x) {
-    const auto &fields =
-        std::get<std::optional<std::list<parser::OpenMPDeclarativeAllocate>>>(
-            x.t);
-    if (fields) {
-      for (const auto &decl : *fields) {
-        Walk(decl);
-      }
-    }
     BeginOpenMP();
     Word("!$OMP ALLOCATE");
     Walk(" (", std::get<std::optional<OmpObjectList>>(x.t), ")");
diff --git a/flang/lib/Semantics/canonicalize-omp.cpp b/flang/lib/Semantics/canonicalize-omp.cpp
index 013fb408214e..dc8a2a4d93af 100644
--- a/flang/lib/Semantics/canonicalize-omp.cpp
+++ b/flang/lib/Semantics/canonicalize-omp.cpp
@@ -15,9 +15,7 @@
 //   1. move structured DoConstruct and OmpEndLoopDirective into
 //      OpenMPLoopConstruct. Compilation will not proceed in case of errors
 //      after this pass.
-//   2. Associate declarative OMP allocation directives with their
-//      respective executable allocation directive
-//   3. TBD
+//   2. TBD
 namespace Fortran::semantics {
 
 using namespace parser::literals;
@@ -48,8 +46,6 @@ public:
     } // Block list
   }
 
-  void Post(parser::ExecutionPart &body) { RewriteOmpAllocations(body); }
-
 private:
   template <typename T> T *GetConstructIf(parser::ExecutionPartConstruct &x) {
     if (auto *y{std::get_if<parser::ExecutableConstruct>(&x.u)}) {
@@ -60,15 +56,6 @@ private:
     return nullptr;
   }
 
-  template <typename T> T *GetOmpIf(parser::ExecutionPartConstruct &x) {
-    if (auto *construct{GetConstructIf<parser::OpenMPConstruct>(x)}) {
-      if (auto *omp{std::get_if<T>(&construct->u)}) {
-        return omp;
-      }
-    }
-    return nullptr;
-  }
-
   void RewriteOpenMPLoopConstruct(parser::OpenMPLoopConstruct &x,
       parser::Block &block, parser::Block::iterator it) {
     // Check the sequence of DoConstruct and OmpEndLoopDirective
@@ -119,36 +106,6 @@ private:
         parser::ToUpperCaseLetters(dir.source.ToString()));
   }
 
-  void RewriteOmpAllocations(parser::ExecutionPart &body) {
-    // Rewrite leading declarative allocations so they are nested
-    // within their respective executable allocate directive
-    //
-    // Original:
-    //   ExecutionPartConstruct -> OpenMPDeclarativeAllocate
-    //   ExecutionPartConstruct -> OpenMPDeclarativeAllocate
-    //   ExecutionPartConstruct -> OpenMPExecutableAllocate
-    //
-    // After rewriting:
-    //   ExecutionPartConstruct -> OpenMPExecutableAllocate
-    //     ExecutionPartConstruct -> OpenMPDeclarativeAllocate
-    //     ExecutionPartConstruct -> OpenMPDeclarativeAllocate
-    for (auto it = body.v.rbegin(); it != body.v.rend();) {
-      if (auto *exec = GetOmpIf<parser::OpenMPExecutableAllocate>(*(it++))) {
-        parser::OpenMPDeclarativeAllocate *decl;
-        std::list<parser::OpenMPDeclarativeAllocate> subAllocates;
-        while (it != body.v.rend() &&
-            (decl = GetOmpIf<parser::OpenMPDeclarativeAllocate>(*it))) {
-          subAllocates.push_front(std::move(*decl));
-          it = decltype(it)(body.v.erase(std::next(it).base()));
-        }
-        if (!subAllocates.empty()) {
-          std::get<std::optional<std::list<parser::OpenMPDeclarativeAllocate>>>(
-              exec->t) = {std::move(subAllocates)};
-        }
-      }
-    }
-  }
-
   parser::Messages &messages_;
 };
 
diff --git a/flang/lib/Semantics/resolve-directives.cpp b/flang/lib/Semantics/resolve-directives.cpp
index 1052c459632e..9eb4d9836491 100644
--- a/flang/lib/Semantics/resolve-directives.cpp
+++ b/flang/lib/Semantics/resolve-directives.cpp
@@ -1691,8 +1691,7 @@ void OmpAttributeVisitor::ResolveOmpObject(
                   }
                 }
                 if (ompFlag == Symbol::Flag::OmpDeclarativeAllocateDirective &&
-                    IsAllocatable(*symbol) &&
-                    !IsNestedInDirective(llvm::omp::Directive::OMPD_allocate)) {
+                    IsAllocatable(*symbol)) {
                   context_.Say(designator.source,
                       "List items specified in the ALLOCATE directive must not "
                       "have the ALLOCATABLE attribute unless the directive is "
diff --git a/flang/test/Parser/OpenMP/allocate-tree-spec-part.f90 b/flang/test/Parser/OpenMP/allocate-tree-spec-part.f90
deleted file mode 100644
index 45a693d2cb04..000000000000
--- a/flang/test/Parser/OpenMP/allocate-tree-spec-part.f90
+++ /dev/null
@@ -1,47 +0,0 @@
-! RUN: %flang_fc1 -fopenmp -fdebug-dump-parse-tree %s | FileCheck %s
-! Ensures associated declarative OMP allocations in the specification
-! part are kept there
-
-program allocate_tree
-    use omp_lib
-    integer, allocatable :: w, xarray(:), zarray(:, :)
-    integer :: f
-!$omp allocate(f) allocator(omp_default_mem_alloc)
-    f = 2
-!$omp allocate(w) allocator(omp_const_mem_alloc)
-!$omp allocate(xarray) allocator(omp_large_cap_mem_alloc)
-!$omp allocate(zarray) allocator(omp_default_mem_alloc)
-!$omp allocate
-    allocate (w, xarray(4), zarray(5, f))
-end program allocate_tree
-
-!CHECK: | | DeclarationConstruct -> SpecificationConstruct -> OpenMPDeclarativeConstruct -> OpenMPDeclarativeAllocate
-!CHECK-NEXT: | | | Verbatim
-!CHECK-NEXT: | | | OmpObjectList -> OmpObject -> Designator -> DataRef -> Name = 'f'
-!CHECK-NEXT: | | | OmpClauseList -> OmpClause -> Allocator -> Scalar -> Integer -> Expr =
-!CHECK-NEXT: | | | | Designator -> DataRef -> Name =
-!CHECK-NEXT: | ExecutionPart -> Block
-!CHECK-NEXT: | | ExecutionPartConstruct -> ExecutableConstruct -> ActionStmt -> AssignmentStmt = 'f=2_4'
-!CHECK-NEXT: | | | Variable = 'f'
-!CHECK-NEXT: | | | | Designator -> DataRef -> Name = 'f'
-!CHECK-NEXT: | | | Expr = '2_4'
-!CHECK-NEXT: | | | | LiteralConstant -> IntLiteralConstant = '2'
-!CHECK-NEXT: | | ExecutionPartConstruct -> ExecutableConstruct -> OpenMPConstruct -> OpenMPExecutableAllocate
-!CHECK-NEXT: | | | Verbatim
-!CHECK-NEXT: | | | OmpClauseList ->
-!CHECK-NEXT: | | | OpenMPDeclarativeAllocate
-!CHECK-NEXT: | | | | Verbatim
-!CHECK-NEXT: | | | | OmpObjectList -> OmpObject -> Designator -> DataRef -> Name = 'w'
-!CHECK-NEXT: | | | | OmpClauseList -> OmpClause -> Allocator -> Scalar -> Integer -> Expr =
-!CHECK-NEXT: | | | | | Designator -> DataRef -> Name =
-!CHECK-NEXT: | | | OpenMPDeclarativeAllocate
-!CHECK-NEXT: | | | | Verbatim
-!CHECK-NEXT: | | | | OmpObjectList -> OmpObject -> Designator -> DataRef -> Name = 'xarray'
-!CHECK-NEXT: | | | | OmpClauseList -> OmpClause -> Allocator -> Scalar -> Integer -> Expr =
-!CHECK-NEXT: | | | | | Designator -> DataRef -> Name =
-!CHECK-NEXT: | | | OpenMPDeclarativeAllocate
-!CHECK-NEXT: | | | | Verbatim
-!CHECK-NEXT: | | | | OmpObjectList -> OmpObject -> Designator -> DataRef -> Name = 'zarray'
-!CHECK-NEXT: | | | | OmpClauseList -> OmpClause -> Allocator -> Scalar -> Integer -> Expr =
-!CHECK-NEXT: | | | | | Designator -> DataRef -> Name =
-!CHECK-NEXT: | | | AllocateStmt
diff --git a/flang/test/Parser/OpenMP/allocate-tree.f90 b/flang/test/Parser/OpenMP/allocate-tree.f90
deleted file mode 100644
index f04e431e74ae..000000000000
--- a/flang/test/Parser/OpenMP/allocate-tree.f90
+++ /dev/null
@@ -1,43 +0,0 @@
-! RUN: %flang_fc1 -fopenmp -fdebug-dump-parse-tree %s | FileCheck %s
-! RUN: %flang_fc1 -fopenmp -fdebug-unparse %s | FileCheck %s --check-prefix="UNPARSE"
-! Ensures associated declarative OMP allocations are nested in their
-! corresponding executable allocate directive
-
-program allocate_tree
-    use omp_lib
-    integer, allocatable :: w, xarray(:), zarray(:, :)
-    integer :: z, t
-    t = 2
-    z = 3
-!$omp allocate(w) allocator(omp_const_mem_alloc)
-!$omp allocate(xarray) allocator(omp_large_cap_mem_alloc)
-!$omp allocate(zarray) allocator(omp_default_mem_alloc)
-!$omp allocate
-    allocate(w, xarray(4), zarray(t, z))
-end program allocate_tree
-
-!CHECK: | | ExecutionPartConstruct -> ExecutableConstruct -> OpenMPConstruct -> OpenMPExecutableAllocate
-!CHECK-NEXT: | | | Verbatim
-!CHECK-NEXT: | | | OmpClauseList ->
-!CHECK-NEXT: | | | OpenMPDeclarativeAllocate
-!CHECK-NEXT: | | | | Verbatim
-!CHECK-NEXT: | | | | OmpObjectList -> OmpObject -> Designator -> DataRef -> Name = 'w'
-!CHECK-NEXT: | | | | OmpClauseList -> OmpClause -> Allocator -> Scalar -> Integer -> Expr =
-!CHECK-NEXT: | | | | | Designator -> DataRef -> Name =
-!CHECK-NEXT: | | | OpenMPDeclarativeAllocate
-!CHECK-NEXT: | | | | Verbatim
-!CHECK-NEXT: | | | | OmpObjectList -> OmpObject -> Designator -> DataRef -> Name = 'xarray'
-!CHECK-NEXT: | | | | OmpClauseList -> OmpClause -> Allocator -> Scalar -> Integer -> Expr =
-!CHECK-NEXT: | | | | | Designator -> DataRef -> Name =
-!CHECK-NEXT: | | | OpenMPDeclarativeAllocate
-!CHECK-NEXT: | | | | Verbatim
-!CHECK-NEXT: | | | | OmpObjectList -> OmpObject -> Designator -> DataRef -> Name = 'zarray'
-!CHECK-NEXT: | | | | OmpClauseList -> OmpClause -> Allocator -> Scalar -> Integer -> Expr =
-!CHECK-NEXT: | | | | | Designator -> DataRef -> Name =
-!CHECK-NEXT: | | | AllocateStmt
-
-!UNPARSE: !$OMP ALLOCATE (w) ALLOCATOR(1_4)
-!UNPARSE-NEXT: !$OMP ALLOCATE (xarray) ALLOCATOR(1_4)
-!UNPARSE-NEXT: !$OMP ALLOCATE (zarray) ALLOCATOR(1_4)
-!UNPARSE-NEXT: !$OMP ALLOCATE
-!UNPARSE-NEXT: ALLOCATE(w, xarray(4_4), zarray(t,z))