Remove empty frame and full evaluators

There are no virtual methods that require different specialization in
dwarf_expr_context class. This means that derived classes
dwarf_expr_executor and dwarf_evaluate_loc_desc are not needed any
more.

As a result of this, the  evaluate_for_locexpr_baton class base class
is now the dwarf_expr_context class.

There might be a need for a better class hierarchy when we know more
about the direction of the future DWARF versions and gdb extensions,
but that is out of the scope of this patch series.

gdb/ChangeLog:

	* dwarf2/frame.c (class dwarf_expr_executor): Remove class.
	(execute_stack_op): Instantiate dwarf_expr_context instead of
	dwarf_evaluate_loc_desc class.
	* dwarf2/loc.c (class dwarf_evaluate_loc_desc): Remove class.
	(dwarf2_evaluate_loc_desc_full): Instantiate dwarf_expr_context
	instead of dwarf_evaluate_loc_desc class.
	(struct evaluate_for_locexpr_baton): Derive from
	dwarf_expr_context.

2 files changed, 5 insertions, 29 deletions

diff --git a/gdb/dwarf2/frame.c b/gdb/dwarf2/frame.c
index 8d42002..c1219d9 100644
--- a/gdb/dwarf2/frame.c
+++ b/gdb/dwarf2/frame.c
@@ -224,22 +224,6 @@ register %s (#%d) at %s"),
     }
 }
 
-class dwarf_expr_executor : public dwarf_expr_context
-{
-public:
-
-  dwarf_expr_executor (dwarf2_per_objfile *per_objfile)
-    : dwarf_expr_context (per_objfile)
-  {}
-
- private:
-
-  void invalid (const char *op) ATTRIBUTE_NORETURN
-  {
-    error (_("%s is invalid in this context"), op);
-  }
-};
-
 static CORE_ADDR
 execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size,
 		  struct frame_info *this_frame, CORE_ADDR initial,
@@ -247,7 +231,7 @@ execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size,
 {
   CORE_ADDR result;
 
-  dwarf_expr_executor ctx (per_objfile);
+  dwarf_expr_context ctx (per_objfile);
   scoped_value_mark free_values;
 
   ctx.frame = this_frame;
diff --git a/gdb/dwarf2/loc.c b/gdb/dwarf2/loc.c
index f0bf701..b985f91 100644
--- a/gdb/dwarf2/loc.c
+++ b/gdb/dwarf2/loc.c
@@ -660,14 +660,6 @@ sect_variable_value (sect_offset sect_off,
 				     type, true);
 }
 
-class dwarf_evaluate_loc_desc : public dwarf_expr_context
-{
-public:
-  dwarf_evaluate_loc_desc (dwarf2_per_objfile *per_objfile)
-    : dwarf_expr_context (per_objfile)
-  {}
-};
-
 /* See dwarf2loc.h.  */
 
 unsigned int entry_values_debug = 0;
@@ -2071,7 +2063,7 @@ dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame,
   if (size == 0)
     return allocate_optimized_out_value (subobj_type);
 
-  dwarf_evaluate_loc_desc ctx (per_objfile);
+  dwarf_expr_context ctx (per_objfile);
   ctx.frame = frame;
   ctx.per_cu = per_cu;
   ctx.obj_address = 0;
@@ -2270,16 +2262,16 @@ dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame,
 					per_objfile, NULL, 0);
 }
 
-/* A specialization of dwarf_evaluate_loc_desc that is used by
+/* A specialization of dwarf_expr_context that is used by
    dwarf2_locexpr_baton_eval.  This subclass exists to handle the case
    where a caller of dwarf2_locexpr_baton_eval passes in some data,
    but with the address being 0.  In this situation, we arrange for
    memory reads to come from the passed-in buffer.  */
 
-struct evaluate_for_locexpr_baton : public dwarf_evaluate_loc_desc
+struct evaluate_for_locexpr_baton : public dwarf_expr_context
 {
   evaluate_for_locexpr_baton (dwarf2_per_objfile *per_objfile)
-    : dwarf_evaluate_loc_desc (per_objfile)
+    : dwarf_expr_context (per_objfile)
   {}
 
   /* The data that was passed in.  */