OpenACC 2.7: default clause support for data constructs

This patch implements the OpenACC 2.7 addition of default(none|present) support
for data constructs.

Now, specifying "default(none|present)" on a data construct turns on same
default clause behavior for all lexically enclosed compute constructs (which
don't already themselves have a default clause).

gcc/c/ChangeLog:
	* c-parser.cc (OACC_DATA_CLAUSE_MASK): Add PRAGMA_OACC_CLAUSE_DEFAULT.

gcc/cp/ChangeLog:
	* parser.cc (OACC_DATA_CLAUSE_MASK): Add PRAGMA_OACC_CLAUSE_DEFAULT.

gcc/fortran/ChangeLog:
	* openmp.cc (OACC_DATA_CLAUSES): Add OMP_CLAUSE_DEFAULT.

gcc/ChangeLog:
	* gimplify.cc (oacc_region_type_name): New function.
	(oacc_default_clause): If no 'default' clause appears on this
	compute construct, see if one appears on a lexically containing
	'data' construct.
	(gimplify_scan_omp_clauses): Upon OMP_CLAUSE_DEFAULT case, set
	ctx->oacc_default_clause_ctx to current context.

gcc/testsuite/ChangeLog:
	* c-c++-common/goacc/default-3.c: Adjust testcase.
	* c-c++-common/goacc/default-4.c: Adjust testcase.
	* c-c++-common/goacc/default-5.c: Adjust testcase.
	* gfortran.dg/goacc/default-3.f95: Adjust testcase.
	* gfortran.dg/goacc/default-4.f: Adjust testcase.
	* gfortran.dg/goacc/default-5.f: Adjust testcase.

Co-authored-by: Thomas Schwinge <thomas@codesourcery.com>

1 files changed, 51 insertions, 13 deletions

diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc
index 320920e..7549436 100644
--- a/gcc/gimplify.cc
+++ b/gcc/gimplify.cc
@@ -7699,6 +7699,25 @@ omp_default_clause (struct gimplify_omp_ctx *ctx, tree decl,
   return flags;
 }
 
+/* Return string name for types of OpenACC constructs from ORT_* values.  */
+
+static const char *
+oacc_region_type_name (enum omp_region_type region_type)
+{
+  switch (region_type)
+    {
+    case ORT_ACC_DATA:
+      return "data";
+    case ORT_ACC_PARALLEL:
+      return "parallel";
+    case ORT_ACC_KERNELS:
+      return "kernels";
+    case ORT_ACC_SERIAL:
+      return "serial";
+    default:
+      gcc_unreachable ();
+    }
+}
 
 /* Determine outer default flags for DECL mentioned in an OACC region
    but not declared in an enclosing clause.  */
@@ -7706,7 +7725,23 @@ omp_default_clause (struct gimplify_omp_ctx *ctx, tree decl,
 static unsigned
 oacc_default_clause (struct gimplify_omp_ctx *ctx, tree decl, unsigned flags)
 {
-  const char *rkind;
+  struct gimplify_omp_ctx *ctx_default = ctx;
+  /* If no 'default' clause appears on this compute construct...  */
+  if (ctx_default->default_kind == OMP_CLAUSE_DEFAULT_SHARED)
+    {
+      /* ..., see if one appears on a lexically containing 'data'
+	 construct.  */
+      while ((ctx_default = ctx_default->outer_context))
+	{
+	  if (ctx_default->region_type == ORT_ACC_DATA
+	      && ctx_default->default_kind != OMP_CLAUSE_DEFAULT_SHARED)
+	    break;
+	}
+      /* If not, reset.  */
+      if (!ctx_default)
+	ctx_default = ctx;
+    }
+
   bool on_device = false;
   bool is_private = false;
   bool declared = is_oacc_declared (decl);
@@ -7738,14 +7773,12 @@ oacc_default_clause (struct gimplify_omp_ctx *ctx, tree decl, unsigned flags)
   switch (ctx->region_type)
     {
     case ORT_ACC_KERNELS:
-      rkind = "kernels";
-
       if (is_private)
 	flags |= GOVD_FIRSTPRIVATE;
       else if (AGGREGATE_TYPE_P (type))
 	{
 	  /* Aggregates default to 'present_or_copy', or 'present'.  */
-	  if (ctx->default_kind != OMP_CLAUSE_DEFAULT_PRESENT)
+	  if (ctx_default->default_kind != OMP_CLAUSE_DEFAULT_PRESENT)
 	    flags |= GOVD_MAP;
 	  else
 	    flags |= GOVD_MAP | GOVD_MAP_FORCE_PRESENT;
@@ -7758,8 +7791,6 @@ oacc_default_clause (struct gimplify_omp_ctx *ctx, tree decl, unsigned flags)
 
     case ORT_ACC_PARALLEL:
     case ORT_ACC_SERIAL:
-      rkind = ctx->region_type == ORT_ACC_PARALLEL ? "parallel" : "serial";
-
       if (is_private)
 	flags |= GOVD_FIRSTPRIVATE;
       else if (on_device || declared)
@@ -7767,7 +7798,7 @@ oacc_default_clause (struct gimplify_omp_ctx *ctx, tree decl, unsigned flags)
       else if (AGGREGATE_TYPE_P (type))
 	{
 	  /* Aggregates default to 'present_or_copy', or 'present'.  */
-	  if (ctx->default_kind != OMP_CLAUSE_DEFAULT_PRESENT)
+	  if (ctx_default->default_kind != OMP_CLAUSE_DEFAULT_PRESENT)
 	    flags |= GOVD_MAP;
 	  else
 	    flags |= GOVD_MAP | GOVD_MAP_FORCE_PRESENT;
@@ -7785,16 +7816,23 @@ oacc_default_clause (struct gimplify_omp_ctx *ctx, tree decl, unsigned flags)
   if (DECL_ARTIFICIAL (decl))
     ; /* We can get compiler-generated decls, and should not complain
 	 about them.  */
-  else if (ctx->default_kind == OMP_CLAUSE_DEFAULT_NONE)
+  else if (ctx_default->default_kind == OMP_CLAUSE_DEFAULT_NONE)
     {
       error ("%qE not specified in enclosing OpenACC %qs construct",
-	     DECL_NAME (lang_hooks.decls.omp_report_decl (decl)), rkind);
-      inform (ctx->location, "enclosing OpenACC %qs construct", rkind);
-    }
-  else if (ctx->default_kind == OMP_CLAUSE_DEFAULT_PRESENT)
+	     DECL_NAME (lang_hooks.decls.omp_report_decl (decl)),
+	     oacc_region_type_name (ctx->region_type));
+      if (ctx_default != ctx)
+	inform (ctx->location, "enclosing OpenACC %qs construct and",
+		oacc_region_type_name (ctx->region_type));
+      inform (ctx_default->location,
+	      "enclosing OpenACC %qs construct with %qs clause",
+	      oacc_region_type_name (ctx_default->region_type),
+	      "default(none)");
+    }
+  else if (ctx_default->default_kind == OMP_CLAUSE_DEFAULT_PRESENT)
     ; /* Handled above.  */
   else
-    gcc_checking_assert (ctx->default_kind == OMP_CLAUSE_DEFAULT_SHARED);
+    gcc_checking_assert (ctx_default->default_kind == OMP_CLAUSE_DEFAULT_SHARED);
 
   return flags;
 }