+
+/*
+ * Allocate an area of size bytes aligned at alignment
+ * at the start or the end of a frame type.
+ * The frame type must have already an fixed layout.
+ */
+entity *frame_alloc_area(ir_type *frame_type, int size, int alignment, int at_start)
+{
+ entity *area;
+ ir_type *tp;
+ ident *name;
+ char buf[32];
+ int frame_align, i, offset, frame_size;
+ static unsigned area_cnt = 0;
+ static ir_type *a_byte = NULL;
+
+ assert(is_frame_type(frame_type));
+ assert(get_type_state(frame_type) == layout_fixed);
+
+ if (! a_byte)
+ a_byte = new_type_primitive(new_id_from_chars("byte", 4), mode_Bu);
+
+ snprintf(buf, sizeof(buf), "area%u", area_cnt++);
+ name = new_id_from_str(buf);
+
+ /* align the size */
+ frame_align = get_type_alignment_bytes(frame_type);
+ size = (size + frame_align - 1) & -frame_align;
+
+ tp = new_type_array(mangle_u(get_type_ident(frame_type), name), 1, a_byte);
+ set_array_bounds_int(tp, 0, 0, size);
+ set_type_alignment_bytes(tp, alignment);
+
+ frame_size = get_type_size_bytes(frame_type);
+ if (at_start) {
+ /* fix all offsets so far */
+ for (i = get_class_n_members(frame_type) - 1; i >= 0; --i) {
+ entity *ent = get_class_member(frame_type, i);
+
+ set_entity_offset_bytes(ent, get_entity_offset_bytes(ent) + size);
+ }
+ /* calculate offset and new type size */
+ offset = 0;
+ frame_size += size;
+ }
+ else {
+ /* calculate offset and new type size */
+ offset = (frame_size + alignment - 1) & -alignment;
+ frame_size = offset + size;
+ }
+
+ area = new_entity(frame_type, name, tp);
+ set_entity_offset_bytes(area, offset);
+ set_type_size_bytes(frame_type, frame_size);
+
+ return area;
+}