[gcc(refs/vendors/redhat/heads/gcc-8-branch)] openmp: Handle clauses with gimple sequences in convert_nonlocal_omp_clauses properly

[gcc(refs/vendors/redhat/heads/gcc-8-branch)] openmp: Handle clauses with gimple sequences in convert_nonlocal_omp_clauses properly

[Jakub Jelinek]

https://gcc.gnu.org/g:5da984d294318dfea6d708e3784b789d6d38a006

commit 5da984d294318dfea6d708e3784b789d6d38a006
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Sat Aug 8 11:10:30 2020 +0200

    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.
    
    (cherry picked from commit 676b5525e8333005bdc1c596ed086f1da27a450f)

Diff:
---
 gcc/tree-nested.c                             | 46 +++++++++++++++++++++------
 libgomp/testsuite/libgomp.fortran/pr93553.f90 | 21 ++++++++++++
 2 files changed, 57 insertions(+), 10 deletions(-)

diff --git a/gcc/tree-nested.c b/gcc/tree-nested.c
index e7ea290065b..d63b4101b67 100644
--- a/gcc/tree-nested.c
+++ b/gcc/tree-nested.c
@@ -1346,12 +1346,22 @@ 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))
@@ -1361,15 +1371,31 @@ 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
index 00000000000..5d6f10febed
--- /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