Merge of the scalar-storage-order branch.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@229965 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 62 insertions, 3 deletions

diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
index bdcb5b25401..53c1d81c0c8 100644
--- a/gcc/c-family/c-common.c
+++ b/gcc/c-family/c-common.c
@@ -339,6 +339,8 @@ static tree handle_no_reorder_attribute (tree *, tree, tree, int,
 static tree handle_const_attribute (tree *, tree, tree, int, bool *);
 static tree handle_transparent_union_attribute (tree *, tree, tree,
 						int, bool *);
+static tree handle_scalar_storage_order_attribute (tree *, tree, tree,
+						   int, bool *);
 static tree handle_constructor_attribute (tree *, tree, tree, int, bool *);
 static tree handle_destructor_attribute (tree *, tree, tree, int, bool *);
 static tree handle_mode_attribute (tree *, tree, tree, int, bool *);
@@ -693,6 +695,8 @@ const struct attribute_spec c_common_attribute_table[] =
   /* The same comments as for noreturn attributes apply to const ones.  */
   { "const",                  0, 0, true,  false, false,
 			      handle_const_attribute, false },
+  { "scalar_storage_order",   1, 1, false, false, false,
+			      handle_scalar_storage_order_attribute, false },
   { "transparent_union",      0, 0, false, false, false,
 			      handle_transparent_union_attribute, false },
   { "constructor",            0, 1, true,  false, false,
@@ -7668,6 +7672,62 @@ handle_const_attribute (tree *node, tree name, tree ARG_UNUSED (args),
   return NULL_TREE;
 }
 
+/* Handle a "scalar_storage_order" attribute; arguments as in
+   struct attribute_spec.handler.  */
+
+static tree
+handle_scalar_storage_order_attribute (tree *node, tree name, tree args,
+				       int flags, bool *no_add_attrs)
+{
+  tree id = TREE_VALUE (args);
+  tree type;
+
+  if (TREE_CODE (*node) == TYPE_DECL
+      && ! (flags & ATTR_FLAG_CXX11))
+    node = &TREE_TYPE (*node);
+  type = *node;
+
+  if (BYTES_BIG_ENDIAN != WORDS_BIG_ENDIAN)
+    {
+      error ("scalar_storage_order is not supported because endianness "
+	    "is not uniform");
+      return NULL_TREE;
+    }
+
+  if (RECORD_OR_UNION_TYPE_P (type) && !c_dialect_cxx ())
+    {
+      bool reverse = false;
+
+      if (TREE_CODE (id) == STRING_CST
+	  && strcmp (TREE_STRING_POINTER (id), "big-endian") == 0)
+	reverse = !BYTES_BIG_ENDIAN;
+      else if (TREE_CODE (id) == STRING_CST
+	       && strcmp (TREE_STRING_POINTER (id), "little-endian") == 0)
+	reverse = BYTES_BIG_ENDIAN;
+      else
+	{
+	  error ("scalar_storage_order argument must be one of \"big-endian\""
+		 " or \"little-endian\"");
+	  return NULL_TREE;
+	}
+
+      if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
+	{
+	  if (reverse)
+	    /* A type variant isn't good enough, since we don't want a cast
+	       to such a type to be removed as a no-op.  */
+	    *node = type = build_duplicate_type (type);
+	}
+
+      TYPE_REVERSE_STORAGE_ORDER (type) = reverse;
+      return NULL_TREE;
+    }
+
+  warning (OPT_Wattributes, "%qE attribute ignored", name);
+  *no_add_attrs = true;
+  return NULL_TREE;
+}
+
 /* Handle a "transparent_union" attribute; arguments as in
    struct attribute_spec.handler.  */
 
@@ -7680,7 +7740,6 @@ handle_transparent_union_attribute (tree *node, tree name,
 
   *no_add_attrs = true;
 
-
   if (TREE_CODE (*node) == TYPE_DECL
       && ! (flags & ATTR_FLAG_CXX11))
     node = &TREE_TYPE (*node);
@@ -7711,8 +7770,8 @@ handle_transparent_union_attribute (tree *node, tree name,
 	  if (c_dialect_cxx ())
 	    goto ignored;
 
-	  /* A type variant isn't good enough, since we don't a cast
-	     to such a type removed as a no-op.  */
+	  /* A type variant isn't good enough, since we don't want a cast
+	     to such a type to be removed as a no-op.  */
 	  *node = type = build_duplicate_type (type);
 	}