vla: introduce new bound type abstraction adapt uses

The rational behind this patch is to get started to implement the feature
described in dwarf4 standard (2.19) Static and Dynamic Values of Attributes.
It adds new BOUND_PROP to store either a constant, exprloc, or reference to
describe an upper-/lower bound of a subrange. Other than that no new features
are introduced.

	* dwarf2read.c (read_subrange_type): Use struct bound_prop for
	declaring high/low bounds and change uses accordingly. Call
	create_range_type instead of create_static_range_type.
	* gdbtypes.c (create_range_type): New function.
	(create_range_type): Convert bounds into struct bound_prop and pass
	them to create_range_type.
	* gdbtypes.h (struct bound_prop): New struct.
	(create_range_type): New function prototype.
	(struct range_bounds): Use struct bound_prop instead of LONGEST for
	high/low bounds. Remove low_undefined/high_undefined and adapt all uses.
	(TYPE_LOW_BOUND,TYPE_HIGH_BOUND): Adapt macros to refer to the static
	part of the bound.
	* parse.c (follow_types): Set high bound kind to BOUND_UNDEFINED.

1 files changed, 44 insertions, 14 deletions

diff --git a/gdb/gdbtypes.h b/gdb/gdbtypes.h
index b5fb5640c9..e91ab97725 100644
--- a/gdb/gdbtypes.h
+++ b/gdb/gdbtypes.h
@@ -399,6 +399,33 @@ enum type_instance_flag_value
 #define TYPE_ADDRESS_CLASS_ALL(t) (TYPE_INSTANCE_FLAGS(t) \
 				   & TYPE_INSTANCE_FLAG_ADDRESS_CLASS_ALL)
 
+/* * Used to store a dynamic property.  */
+
+struct dynamic_prop
+{
+  /* Determine which field of the union dynamic_prop.data is used.  */
+  enum
+  {
+    PROP_UNDEFINED, /* Not defined.  */
+    PROP_CONST,     /* Constant.  */
+    PROP_LOCEXPR,   /* Location expression.  */
+    PROP_LOCLIST    /* Location list.  */
+  } kind;
+
+  /* Storage for dynamic or static value.  */
+  union data
+  {
+    /* Storage for constant property.  */
+
+    LONGEST const_val;
+
+    /* Storage for dynamic property.  */
+
+    void *baton;
+  } data;
+};
+
+
 /* * Determine which field of the union main_type.fields[x].loc is
    used.  */
 
@@ -630,19 +657,11 @@ struct main_type
     {
       /* * Low bound of range.  */
 
-      LONGEST low;
+      struct dynamic_prop low;
 
       /* * High bound of range.  */
 
-      LONGEST high;
-
-      /* * Flags indicating whether the values of low and high are
-         valid.  When true, the respective range value is
-         undefined.  Currently used only for FORTRAN arrays.  */
-           
-      char low_undefined;
-      char high_undefined;
-
+      struct dynamic_prop high;
     } *bounds;
 
   } flds_bnds;
@@ -1155,12 +1174,18 @@ extern void allocate_gnat_aux_type (struct type *);
 
 #define TYPE_INDEX_TYPE(type) TYPE_FIELD_TYPE (type, 0)
 #define TYPE_RANGE_DATA(thistype) TYPE_MAIN_TYPE(thistype)->flds_bnds.bounds
-#define TYPE_LOW_BOUND(range_type) TYPE_RANGE_DATA(range_type)->low
-#define TYPE_HIGH_BOUND(range_type) TYPE_RANGE_DATA(range_type)->high
+#define TYPE_LOW_BOUND(range_type) \
+  TYPE_RANGE_DATA(range_type)->low.data.const_val
+#define TYPE_HIGH_BOUND(range_type) \
+  TYPE_RANGE_DATA(range_type)->high.data.const_val
 #define TYPE_LOW_BOUND_UNDEFINED(range_type) \
-   TYPE_RANGE_DATA(range_type)->low_undefined
+  (TYPE_RANGE_DATA(range_type)->low.kind == PROP_UNDEFINED)
 #define TYPE_HIGH_BOUND_UNDEFINED(range_type) \
-   TYPE_RANGE_DATA(range_type)->high_undefined
+  (TYPE_RANGE_DATA(range_type)->high.kind == PROP_UNDEFINED)
+#define TYPE_HIGH_BOUND_KIND(range_type) \
+  TYPE_RANGE_DATA(range_type)->high.kind
+#define TYPE_LOW_BOUND_KIND(range_type) \
+  TYPE_RANGE_DATA(range_type)->low.kind
 
 /* Moto-specific stuff for FORTRAN arrays.  */
 
@@ -1628,9 +1653,14 @@ extern struct type *lookup_function_type_with_arguments (struct type *,
 extern struct type *create_static_range_type (struct type *, struct type *,
 					      LONGEST, LONGEST);
 
+
 extern struct type *create_array_type_with_stride
   (struct type *, struct type *, struct type *, unsigned int);
 
+extern struct type *create_range_type (struct type *, struct type *,
+				       const struct dynamic_prop *,
+				       const struct dynamic_prop *);
+
 extern struct type *create_array_type (struct type *, struct type *,
 				       struct type *);