openmp: Handle clauses with gimple sequences in convert_nonlocal_omp_clauses properly

If the walk_body on the various sequences of reduction, lastprivate and/or linear
clauses needs to create a temporary variable, we should declare that variable
in that sequence rather than outside, where it would need to be privatized inside of
the construct.

2020-08-08  Jakub Jelinek  <jakub@redhat.com>

	PR fortran/93553
	* tree-nested.c (convert_nonlocal_omp_clauses): For
	OMP_CLAUSE_REDUCTION, OMP_CLAUSE_LASTPRIVATE and OMP_CLAUSE_LINEAR
	save info->new_local_var_chain around walks of the clause gimple
	sequences and declare_vars if needed into the sequence.

2020-08-08  Tobias Burnus  <tobias@codesourcery.com>

	PR fortran/93553
	* testsuite/libgomp.fortran/pr93553.f90: New test.

diff --git a/gcc/tree-nested.c b/gcc/tree-nested.c
index 6ce89a7bd8e21bc3abf6acfaf5c71579d2a6153d..f74a727dea15f5da963bfe4326a042e78b9d50c4 100644 (file)
--- a/gcc/tree-nested.c
+++ b/gcc/tree-nested.c
@@ -1419,12 +1419,22 @@ convert_nonlocal_omp_clauses (tree *pclauses, struct walk_stmt_info *wi)
              if (OMP_CLAUSE_REDUCTION_DECL_PLACEHOLDER (clause))
                DECL_CONTEXT (OMP_CLAUSE_REDUCTION_DECL_PLACEHOLDER (clause))
                  = info->context;
+             tree save_local_var_chain = info->new_local_var_chain;
+             info->new_local_var_chain = NULL;
+             gimple_seq *seq = &OMP_CLAUSE_REDUCTION_GIMPLE_INIT (clause);
              walk_body (convert_nonlocal_reference_stmt,
-                        convert_nonlocal_reference_op, info,
-                        &OMP_CLAUSE_REDUCTION_GIMPLE_INIT (clause));
+                        convert_nonlocal_reference_op, info, seq);
+             if (info->new_local_var_chain)
+               declare_vars (info->new_local_var_chain,
+                             gimple_seq_first_stmt (*seq), false);
+             info->new_local_var_chain = NULL;
+             seq = &OMP_CLAUSE_REDUCTION_GIMPLE_MERGE (clause);
              walk_body (convert_nonlocal_reference_stmt,
-                        convert_nonlocal_reference_op, info,
-                        &OMP_CLAUSE_REDUCTION_GIMPLE_MERGE (clause));
+                        convert_nonlocal_reference_op, info, seq);
+             if (info->new_local_var_chain)
+               declare_vars (info->new_local_var_chain,
+                             gimple_seq_first_stmt (*seq), false);
+             info->new_local_var_chain = save_local_var_chain;
              DECL_CONTEXT (OMP_CLAUSE_REDUCTION_PLACEHOLDER (clause))
                = old_context;
              if (OMP_CLAUSE_REDUCTION_DECL_PLACEHOLDER (clause))
@@ -1434,15 +1444,31 @@ convert_nonlocal_omp_clauses (tree *pclauses, struct walk_stmt_info *wi)
          break;
 
        case OMP_CLAUSE_LASTPRIVATE:
-         walk_body (convert_nonlocal_reference_stmt,
-                    convert_nonlocal_reference_op, info,
-                    &OMP_CLAUSE_LASTPRIVATE_GIMPLE_SEQ (clause));
+         {
+           tree save_local_var_chain = info->new_local_var_chain;
+           info->new_local_var_chain = NULL;
+           gimple_seq *seq = &OMP_CLAUSE_LASTPRIVATE_GIMPLE_SEQ (clause);
+           walk_body (convert_nonlocal_reference_stmt,
+                      convert_nonlocal_reference_op, info, seq);
+           if (info->new_local_var_chain)
+             declare_vars (info->new_local_var_chain,
+                           gimple_seq_first_stmt (*seq), false);
+           info->new_local_var_chain = save_local_var_chain;
+         }
          break;
 
        case OMP_CLAUSE_LINEAR:
-         walk_body (convert_nonlocal_reference_stmt,
-                    convert_nonlocal_reference_op, info,
-                    &OMP_CLAUSE_LINEAR_GIMPLE_SEQ (clause));
+         {
+           tree save_local_var_chain = info->new_local_var_chain;
+           info->new_local_var_chain = NULL;
+           gimple_seq *seq = &OMP_CLAUSE_LINEAR_GIMPLE_SEQ (clause);
+           walk_body (convert_nonlocal_reference_stmt,
+                      convert_nonlocal_reference_op, info, seq);
+           if (info->new_local_var_chain)
+             declare_vars (info->new_local_var_chain,
+                           gimple_seq_first_stmt (*seq), false);
+           info->new_local_var_chain = save_local_var_chain;
+         }
          break;
 
        default:

diff --git a/libgomp/testsuite/libgomp.fortran/pr93553.f90 b/libgomp/testsuite/libgomp.fortran/pr93553.f90
new file mode 100644 (file)
index 0000000..5d6f10f
--- /dev/null
+++ b/libgomp/testsuite/libgomp.fortran/pr93553.f90
@@ -0,0 +1,21 @@
+program p
+   implicit none
+   integer :: x(8) = 0
+   call sub(x)
+end
+subroutine sub(x)
+   implicit none
+   integer i
+   integer :: x(8)
+   integer :: c(8) = [(11*i, i=1,8)]
+   call s
+   if (any (x /= c)) stop 1
+contains
+   subroutine s
+      integer :: i
+      !$omp parallel do reduction(+:x)
+      do i = 1, 8
+         x(i) = c(i)
+      end do
+   end
+end