[Flang][OpenMP] Add restriction about subobjects to firstprivate and … (llvm#89608)

…lastprivate

OpenMP 5.2 standard (Section 5.3) defines privatization for list items.
Section 3.2.1 in the standard defines list items to exclude variables
that are part of other variables.

This patch adds the restriction to firstprivate and lastprivates, it was
previously added for privates.

Fixes llvm#67227

Note: The specific checks that are added here are explicitly called out
in OpenMP 4.0
(https://www.openmp.org/wp-content/uploads/OpenMP4.0.0.pdf) Sections
2.14.3.4 and 2.14.3.5 but in later standards have become implicit
through other definitions.

Author: kiranchandramohan

flang/lib/Semantics/check-omp-structure.cpp

@@ -2471,11 +2471,11 @@ void OmpStructureChecker::Enter(const parser::OmpClause::Ordered &x) {
 
 void OmpStructureChecker::Enter(const parser::OmpClause::Shared &x) {
   CheckAllowed(llvm::omp::Clause::OMPC_shared);
-  CheckIsVarPartOfAnotherVar(GetContext().clauseSource, x.v);
+  CheckIsVarPartOfAnotherVar(GetContext().clauseSource, x.v, "SHARED");
 }
 void OmpStructureChecker::Enter(const parser::OmpClause::Private &x) {
   CheckAllowed(llvm::omp::Clause::OMPC_private);
-  CheckIsVarPartOfAnotherVar(GetContext().clauseSource, x.v);
+  CheckIsVarPartOfAnotherVar(GetContext().clauseSource, x.v, "PRIVATE");
   CheckIntentInPointer(x.v, llvm::omp::Clause::OMPC_private);
 }
 
@@ -2513,7 +2513,8 @@ bool OmpStructureChecker::IsDataRefTypeParamInquiry(
 }
 
 void OmpStructureChecker::CheckIsVarPartOfAnotherVar(
-    const parser::CharBlock &source, const parser::OmpObjectList &objList) {
+    const parser::CharBlock &source, const parser::OmpObjectList &objList,
+    llvm::StringRef clause) {
   for (const auto &ompObject : objList.v) {
     common::visit(
         common::visitors{
@@ -2539,7 +2540,8 @@ void OmpStructureChecker::CheckIsVarPartOfAnotherVar(
                     context_.Say(source,
                         "A variable that is part of another variable (as an "
                         "array or structure element) cannot appear in a "
-                        "PRIVATE or SHARED clause"_err_en_US);
+                        "%s clause"_err_en_US,
+                        clause.data());
                   }
                 }
               }
@@ -2552,6 +2554,8 @@ void OmpStructureChecker::CheckIsVarPartOfAnotherVar(
 
 void OmpStructureChecker::Enter(const parser::OmpClause::Firstprivate &x) {
   CheckAllowed(llvm::omp::Clause::OMPC_firstprivate);
+
+  CheckIsVarPartOfAnotherVar(GetContext().clauseSource, x.v, "FIRSTPRIVATE");
   CheckIsLoopIvPartOfClause(llvmOmpClause::OMPC_firstprivate, x.v);
 
   SymbolSourceMap currSymbols;
@@ -2888,6 +2892,8 @@ void OmpStructureChecker::Enter(const parser::OmpClause::Copyprivate &x) {
 void OmpStructureChecker::Enter(const parser::OmpClause::Lastprivate &x) {
   CheckAllowed(llvm::omp::Clause::OMPC_lastprivate);
 
+  CheckIsVarPartOfAnotherVar(GetContext().clauseSource, x.v, "LASTPRIVATE");
+
   DirectivesClauseTriple dirClauseTriple;
   SymbolSourceMap currSymbols;
   GetSymbolsInObjectList(x.v, currSymbols);

flang/lib/Semantics/check-omp-structure.h

@@ -163,8 +163,8 @@ class OmpStructureChecker
   void CheckDependArraySection(
       const common::Indirection<parser::ArrayElement> &, const parser::Name &);
   bool IsDataRefTypeParamInquiry(const parser::DataRef *dataRef);
-  void CheckIsVarPartOfAnotherVar(
-      const parser::CharBlock &source, const parser::OmpObjectList &objList);
+  void CheckIsVarPartOfAnotherVar(const parser::CharBlock &source,
+      const parser::OmpObjectList &objList, llvm::StringRef clause = "");
   void CheckThreadprivateOrDeclareTargetVar(
       const parser::OmpObjectList &objList);
   void CheckSymbolNames(

flang/test/Semantics/OpenMP/firstprivate02.f90

@@ -0,0 +1,20 @@
+! RUN: %python %S/../test_errors.py %s %flang -fopenmp
+! OpenMP Version 5.2, Sections 3.2.1 & 5.3
+subroutine omp_firstprivate(init)
+  integer :: init
+  integer :: a(10)
+  type my_type
+    integer :: val
+  end type my_type
+  type(my_type) :: my_var
+
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a FIRSTPRIVATE clause
+  !$omp parallel firstprivate(a(2))
+    a(2) = init
+  !$omp end parallel
+
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a FIRSTPRIVATE clause
+  !$omp parallel firstprivate(my_var%val)
+    my_var%val = init
+  !$omp end parallel
+end subroutine

flang/test/Semantics/OpenMP/lastprivate03.f90

@@ -0,0 +1,24 @@
+! RUN: %python %S/../test_errors.py %s %flang -fopenmp
+! OpenMP Version 5.2, Sections 3.2.1 & 5.3
+subroutine omp_lastprivate(init)
+  integer :: init
+  integer :: i, a(10)
+  type my_type
+    integer :: val
+  end type my_type
+  type(my_type) :: my_var
+
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a LASTPRIVATE clause
+  !$omp do lastprivate(a(2))
+  do i=1, 10
+    a(2) = init
+  end do
+  !$omp end do
+
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a LASTPRIVATE clause
+  !$omp do lastprivate(my_var%val)
+  do i=1, 10
+    my_var%val = init
+  end do
+  !$omp end do
+end subroutine

flang/test/Semantics/OpenMP/parallel-private01.f90

@@ -10,7 +10,7 @@ program omp_parallel_private
 
   type(my_type) :: my_var
 
-  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE clause
   !$omp parallel private(my_var%array)
   do i = 1, 10
     c(i) = a(i) + b(i) + k

flang/test/Semantics/OpenMP/parallel-private02.f90

@@ -10,7 +10,7 @@ program omp_parallel_private
     array(i) = i
   end do
 
-  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE clause
   !$omp parallel private(array(i))
   do i = 1, 10
     c(i) = a(i) + b(i) + k

flang/test/Semantics/OpenMP/parallel-private03.f90

@@ -17,7 +17,7 @@ program omp_parallel_private
     arr(i) = 0.0
   end do
 
-  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE clause
   !$omp parallel private(arr(i),intx)
   do i = 1, 10
     c(i) = a(i) + b(i) + k

flang/test/Semantics/OpenMP/parallel-private04.f90

@@ -17,7 +17,7 @@ program omp_parallel_private
     arr(i) = 0.0
   end do
 
-  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE clause
   !$omp parallel private(arr,intx,my_var%array(1))
   do i = 1, 10
     c(i) = a(i) + b(i) + k

flang/test/Semantics/OpenMP/parallel-sections01.f90

@@ -17,10 +17,10 @@ program OmpConstructSections01
    do i = 1, 10
       array(i) = i
    end do
-!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a SHARED clause
 !$omp parallel sections shared(array(i))
 !$omp end parallel sections
-!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a SHARED clause
 !$omp parallel sections shared(my_var%array)
 !$omp end parallel sections
 
@@ -30,7 +30,7 @@ program OmpConstructSections01
    if (NT) 20, 30, 40
 !ERROR: invalid branch into an OpenMP structured block
    goto 20
-!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE clause
 !$omp parallel sections private(my_var%array)
    !$omp section
    print *, "This is a single statement structured block"
@@ -53,7 +53,7 @@ program OmpConstructSections01
 30 print *, "Error in opening file"
 !$omp end parallel sections
 10 print *, 'Jump from section'
-!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+!ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE clause
 !$omp parallel sections private(array(i))
    !$omp section
 40 print *, 'Error in opening file'

flang/test/Semantics/OpenMP/parallel-shared01.f90

@@ -10,7 +10,7 @@ program omp_parallel_shared
 
   type(my_type) :: my_var
 
-  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a PRIVATE or SHARED clause
+  !ERROR: A variable that is part of another variable (as an array or structure element) cannot appear in a SHARED clause
   !$omp parallel shared(my_var%array)
   do i = 1, 10
     c(i) = a(i) + b(i) +  k