[gomp4] make fortran loop variables implicitly private in openacc

2014-08-11  Cesar Philippidis  <cesar@codesourcery.com>

	gcc/fortran/
	* openmp.c (oacc_compatible_clauses): New function.
	(resolve_omp_clauses): Use it.
	(oacc_current_ctx): Move it near omp_current_ctx.
	(gfc_resolve_do_iterator): Handle OpenACC index variables.
	(gfc_resolve_oacc_blocks): Initialize ctx.share_clauses and
	ctx.private_iterators.

	gcc/testsuite/
	* gfortran.dg/goacc/private-1.f95: New test.


diff --git a/gcc/fortran/openmp.c b/gcc/fortran/openmp.c
index 91e00c4..2c91597 100644
--- a/gcc/fortran/openmp.c
+++ b/gcc/fortran/openmp.c
@@ -2713,6 +2713,29 @@  resolve_omp_udr_clause (gfc_omp_namelist *n, gfc_namespace *ns,
   return copy;
 }
 
+/* Returns true if clause in list 'list' is compatible with any of
+   of the clauses in lists [0..list-1].  E.g., a reduction variable may
+   appear in both reduction and private clauses, so this function
+   will return true in this case.  */
+
+static bool
+oacc_compatible_clauses (gfc_omp_clauses *clauses, int list,
+			   gfc_symbol *sym, bool openacc)
+{
+  gfc_omp_namelist *n;
+
+  if (!openacc)
+    return false;
+
+  if (list != OMP_LIST_REDUCTION)
+    return false;
+
+  for (n = clauses->lists[OMP_LIST_PRIVATE]; n; n = n->next)
+    if (n->sym == sym)
+      return true;
+
+  return false;
+}
 
 /* OpenMP directive resolving routines.  */
 
@@ -2826,7 +2849,8 @@  resolve_omp_clauses (gfc_code *code, locus *where,
 	&& list != OMP_LIST_TO)
       for (n = omp_clauses->lists[list]; n; n = n->next)
 	{
-	  if (n->sym->mark)
+	  if (n->sym->mark && !oacc_compatible_clauses (omp_clauses, list,
+							n->sym, openacc))
 	    gfc_error ("Symbol '%s' present on multiple clauses at %L",
 		       n->sym->name, where);
 	  else
@@ -3791,6 +3815,9 @@  struct omp_context
 static gfc_code *omp_current_do_code;
 static int omp_current_do_collapse;
 
+typedef struct omp_context oacc_context;
+oacc_context *oacc_current_ctx;
+
 void
 gfc_resolve_omp_do_blocks (gfc_code *code, gfc_namespace *ns)
 {
@@ -3906,6 +3933,8 @@  gfc_resolve_do_iterator (gfc_code *code, gfc_symbol *sym)
 {
   int i = omp_current_do_collapse;
   gfc_code *c = omp_current_do_code;
+  bool openacc = omp_current_ctx == NULL;
+  omp_context *current_ctx = openacc ? oacc_current_ctx : omp_current_ctx;
 
   if (sym->attr.threadprivate)
     return;
@@ -3922,15 +3951,15 @@  gfc_resolve_do_iterator (gfc_code *code, gfc_symbol *sym)
       c = c->block->next;
     }
 
-  if (omp_current_ctx == NULL)
+  if (current_ctx == NULL)
     return;
 
-  if (pointer_set_contains (omp_current_ctx->sharing_clauses, sym))
+  if (!openacc && pointer_set_contains (current_ctx->sharing_clauses, sym))
     return;
 
-  if (! pointer_set_insert (omp_current_ctx->private_iterators, sym))
+  if (! pointer_set_insert (current_ctx->private_iterators, sym))
     {
-      gfc_omp_clauses *omp_clauses = omp_current_ctx->code->ext.omp_clauses;
+      gfc_omp_clauses *omp_clauses = current_ctx->code->ext.omp_clauses;
       gfc_omp_namelist *p;
 
       p = gfc_get_omp_namelist ();
@@ -4106,9 +4135,6 @@  resolve_omp_do (gfc_code *code)
     }
 }
 
-typedef struct omp_context oacc_context;
-oacc_context *oacc_current_ctx;
-
 static bool
 oacc_is_parallel (gfc_code *code)
 {
@@ -4424,6 +4450,8 @@  gfc_resolve_oacc_blocks (gfc_code *code, gfc_namespace *ns)
   resolve_oacc_loop_blocks (code);
 
   ctx.code = code;
+  ctx.sharing_clauses = NULL;
+  ctx.private_iterators = pointer_set_create ();
   ctx.previous = oacc_current_ctx;
   oacc_current_ctx = &ctx;
 
diff --git a/gcc/testsuite/gfortran.dg/goacc/private-1.f95 b/gcc/testsuite/gfortran.dg/goacc/private-1.f95
new file mode 100644
index 0000000..4eaec4f
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/goacc/private-1.f95
@@ -0,0 +1,39 @@ 
+! { dg-do compile } 
+! { dg-additional-options "-fdump-tree-omplower" } 
+
+! test for implicit private clauses in do loops
+
+program test
+  implicit none
+  integer :: i, j, k
+  logical :: l
+
+  !$acc parallel
+  !$acc loop
+  do i = 1, 100
+  end do
+  !$acc end parallel
+
+  !$acc parallel
+  !$acc loop
+  do i = 1, 100
+     do j = 1, 100
+     end do
+  end do
+  !$acc end parallel
+
+  !$acc parallel
+  !$acc loop
+  do i = 1, 100
+     do j = 1, 100
+        do k = 1, 100
+        end do
+     end do
+  end do
+  !$acc end parallel
+end program test
+! { dg-prune-output "unimplemented" }
+! { dg-final { scan-tree-dump-times "pragma acc parallel" 3 "omplower" } } 
+! { dg-final { scan-tree-dump-times "private\\(i\\)" 3 "omplower" } } 
+! { dg-final { scan-tree-dump-times "private\\(j\\)" 2 "omplower" } } 
+! { dg-final { scan-tree-dump-times "private\\(k\\)" 1 "omplower" } }