gdb: Convert language_data::la_exp_desc to a method

Convert language_data::la_exp_desc member variable to a virtual
method language_defn::expression_ops.  The change of names brings this
method more into line with the existing varobj_ops method, that also
returns a table of function pointers.

There should be no user visible changes after this commit.

gdb/ChangeLog:

	* ada-lang.c (ada_language_data): Remove la_exp_desc initializer.
	(ada_language::expression_ops): New member function.
	* c-lang.c (c_language_data): Remove la_exp_desc initializer.
	(c_language::expression_ops): New member function.
	(cplus_language_data): Remove la_exp_desc initializer.
	(cplus_language::expression_ops): New member function.
	(asm_language_data): Remove la_exp_desc initializer.
	(asm_language::expression_ops): New member function.
	(minimal_language_data): Remove la_exp_desc initializer.
	(minimal_language::expression_ops): New member function.
	* d-lang.c (d_language_data): Remove la_exp_desc initializer.
	(d_language::expression_ops): New member function.
	* eval.c (evaluate_subexp): Update call to expression_ops.
	* expprint.c (print_subexp): Likewise.
	(op_name): Likewise.
	(dump_subexp_body): Likewise.
	* f-lang.c (f_language_data): Remove la_exp_desc initializer.
	(f_language::expression_ops): New member function.
	* go-lang.c (go_language_data): Remove la_exp_desc initializer.
	(go_language::expression_ops): New member function.
	* language.c (language_defn::expression_ops): New function.
	(unknown_language_data): Remove la_exp_desc initializer.
	(auto_language_data): Likewise.
	* language.h (language_data): Remove la_exp_desc field.
	(language_defn::expression_ops): Declare new member function.
	* m2-lang.c (m2_language_data): Remove la_exp_desc initializer.
	(m2_language::expression_ops): New member function.
	* objc-lang.c (objc_language_data): Remove la_exp_desc
	initializer.
	* opencl-lang.c (opencl_language_data): Remove la_exp_desc
	initializer.
	(opencl_language::expression_ops): New member function.
	* p-lang.c (pascal_language_data): Remove la_exp_desc initializer.
	* parse.c (operator_length): Update call to expression_ops.
	(exp_iterate): Likewise.
	* rust-lang.c (rust_language_data): Remove la_exp_desc
	initializer.
	(ruse_language::expression_ops): New member function.

gdb/ChangeLog

@@ -1,3 +1,44 @@
+2020-09-16  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* ada-lang.c (ada_language_data): Remove la_exp_desc initializer.
+	(ada_language::expression_ops): New member function.
+	* c-lang.c (c_language_data): Remove la_exp_desc initializer.
+	(c_language::expression_ops): New member function.
+	(cplus_language_data): Remove la_exp_desc initializer.
+	(cplus_language::expression_ops): New member function.
+	(asm_language_data): Remove la_exp_desc initializer.
+	(asm_language::expression_ops): New member function.
+	(minimal_language_data): Remove la_exp_desc initializer.
+	(minimal_language::expression_ops): New member function.
+	* d-lang.c (d_language_data): Remove la_exp_desc initializer.
+	(d_language::expression_ops): New member function.
+	* eval.c (evaluate_subexp): Update call to expression_ops.
+	* expprint.c (print_subexp): Likewise.
+	(op_name): Likewise.
+	(dump_subexp_body): Likewise.
+	* f-lang.c (f_language_data): Remove la_exp_desc initializer.
+	(f_language::expression_ops): New member function.
+	* go-lang.c (go_language_data): Remove la_exp_desc initializer.
+	(go_language::expression_ops): New member function.
+	* language.c (language_defn::expression_ops): New function.
+	(unknown_language_data): Remove la_exp_desc initializer.
+	(auto_language_data): Likewise.
+	* language.h (language_data): Remove la_exp_desc field.
+	(language_defn::expression_ops): Declare new member function.
+	* m2-lang.c (m2_language_data): Remove la_exp_desc initializer.
+	(m2_language::expression_ops): New member function.
+	* objc-lang.c (objc_language_data): Remove la_exp_desc
+	initializer.
+	* opencl-lang.c (opencl_language_data): Remove la_exp_desc
+	initializer.
+	(opencl_language::expression_ops): New member function.
+	* p-lang.c (pascal_language_data): Remove la_exp_desc initializer.
+	* parse.c (operator_length): Update call to expression_ops.
+	(exp_iterate): Likewise.
+	* rust-lang.c (rust_language_data): Remove la_exp_desc
+	initializer.
+	(ruse_language::expression_ops): New member function.
+
 2020-09-16  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* ada-lang.c (ada_language_data): Remove la_varobj_ops

gdb/ada-lang.c

@@ -13708,7 +13708,6 @@ ada_get_symbol_name_matcher (const lookup_name_info &lookup_name)
 
 extern const struct language_data ada_language_data =
 {
-  &ada_exp_descriptor,
   ada_op_print_tab,             /* expression operators for printing */
 };
 
@@ -14206,6 +14205,11 @@ public:
   const struct lang_varobj_ops *varobj_ops () const override
   { return &ada_varobj_ops; }
 
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &ada_exp_descriptor; }
+
 protected:
   /* See language.h.  */
 

gdb/c-lang.c

@@ -875,7 +875,6 @@ const struct exp_descriptor exp_descriptor_c =
 
 extern const struct language_data c_language_data =
 {
-  &exp_descriptor_c,
   c_op_print_tab,		/* expression operators for printing */
 };
 
@@ -947,6 +946,11 @@ public:
 
   enum macro_expansion macro_expansion () const override
   { return macro_expansion_c; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_c; }
 };
 
 /* Single instance of the C language class.  */
@@ -985,7 +989,6 @@ enum cplus_primitive_types {
 
 extern const struct language_data cplus_language_data =
 {
-  &exp_descriptor_c,
   c_op_print_tab,		/* expression operators for printing */
 };
 
@@ -1179,6 +1182,11 @@ public:
   const struct lang_varobj_ops *varobj_ops () const override
   { return &cplus_varobj_ops; }
 
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_c; }
+
 protected:
 
   /* See language.h.  */
@@ -1198,7 +1206,6 @@ static cplus_language cplus_language_defn;
 
 extern const struct language_data asm_language_data =
 {
-  &exp_descriptor_c,
   c_op_print_tab,		/* expression operators for printing */
 };
 
@@ -1257,6 +1264,11 @@ public:
 
   enum macro_expansion macro_expansion () const override
   { return macro_expansion_c; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_c; }
 };
 
 /* The single instance of the ASM language class.  */
@@ -1269,7 +1281,6 @@ static asm_language asm_language_defn;
 
 extern const struct language_data minimal_language_data =
 {
-  &exp_descriptor_c,
   c_op_print_tab,		/* expression operators for printing */
 };
 
@@ -1317,6 +1328,11 @@ public:
 
   enum macro_expansion macro_expansion () const override
   { return macro_expansion_c; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_c; }
 };
 
 /* The single instance of the minimal language class.  */

gdb/d-lang.c

@@ -128,7 +128,6 @@ enum d_primitive_types {
 
 extern const struct language_data d_language_data =
 {
-  &exp_descriptor_c,
   d_op_print_tab,		/* Expression operators for printing.  */
 };
 
@@ -276,6 +275,11 @@ public:
 
   const char *name_of_this () const override
   { return "this"; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_c; }
 };
 
 /* Single instance of the D language class.  */

gdb/eval.c

@@ -74,7 +74,7 @@ evaluate_subexp (struct type *expect_type, struct expression *exp,
       && !thread_stack_temporaries_enabled_p (inferior_thread ()))
     stack_temporaries.emplace (inferior_thread ());
 
-  retval = (*exp->language_defn->la_exp_desc->evaluate_exp)
+  retval = (*exp->language_defn->expression_ops ()->evaluate_exp)
     (expect_type, exp, pos, noside);
 
   if (stack_temporaries.has_value ()

gdb/expprint.c

@@ -50,7 +50,8 @@ void
 print_subexp (struct expression *exp, int *pos,
 	      struct ui_file *stream, enum precedence prec)
 {
-  exp->language_defn->la_exp_desc->print_subexp (exp, pos, stream, prec);
+  exp->language_defn->expression_ops ()->print_subexp (exp, pos, stream,
+						       prec);
 }
 
 /* Standard implementation of print_subexp for use in language_defn
@@ -692,7 +693,7 @@ op_name (struct expression *exp, enum exp_opcode opcode)
 		 unsigned (opcode));
       return cell;
     }
-  return exp->language_defn->la_exp_desc->op_name (opcode);
+  return exp->language_defn->expression_ops ()->op_name (opcode);
 }
 
 /* Default name for the standard operator OPCODE (i.e., one defined in
@@ -793,7 +794,8 @@ dump_subexp (struct expression *exp, struct ui_file *stream, int elt)
 static int
 dump_subexp_body (struct expression *exp, struct ui_file *stream, int elt)
 {
-  return exp->language_defn->la_exp_desc->dump_subexp_body (exp, stream, elt);
+  return exp->language_defn->expression_ops ()->dump_subexp_body (exp, stream,
+								  elt);
 }
 
 /* Default value for subexp_body in exp_descriptor vector.  */

gdb/f-lang.c

@@ -486,7 +486,6 @@ static const struct exp_descriptor exp_descriptor_f =
 
 extern const struct language_data f_language_data =
 {
-  &exp_descriptor_f,
   f_op_print_tab,		/* expression operators for printing */
 };
 
@@ -732,6 +731,11 @@ public:
   enum array_ordering array_ordering () const override
   { return array_column_major; }
 
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_f; }
+
 protected:
 
   /* See language.h.  */

gdb/go-lang.c

@@ -508,7 +508,6 @@ enum go_primitive_types {
 
 extern const struct language_data go_language_data =
 {
-  &exp_descriptor_c,
   go_op_print_tab,		/* Expression operators for printing.  */
 };
 
@@ -637,6 +636,11 @@ public:
 
   bool store_sym_names_in_linkage_form_p () const override
   { return true; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_c; }
 };
 
 /* Single instance of the Go language class.  */

gdb/language.c

@@ -774,6 +774,14 @@ language_defn::varobj_ops () const
   return &c_varobj_ops;
 }
 
+/* See language.h.  */
+
+const struct exp_descriptor *
+language_defn::expression_ops () const
+{
+  return &exp_descriptor_standard;
+}
+
 /* Return true if TYPE is a string type, otherwise return false.  This
    default implementation only detects TYPE_CODE_STRING.  */
 
@@ -808,7 +816,6 @@ unknown_language_arch_info (struct gdbarch *gdbarch,
 
 extern const struct language_data unknown_language_data =
 {
-  &exp_descriptor_standard,
   unk_op_print_tab,		/* expression operators for printing */
 };
 
@@ -940,7 +947,6 @@ static unknown_language unknown_language_defn;
 
 extern const struct language_data auto_language_data =
 {
-  &exp_descriptor_standard,
   unk_op_print_tab,		/* expression operators for printing */
 };
 

gdb/language.h

@@ -168,11 +168,6 @@ extern const char *default_word_break_characters (void);
 
 struct language_data
   {
-    /* Definitions related to expression printing, prefixifying, and
-       dumping.  */
-
-    const struct exp_descriptor *la_exp_desc;
-
     /* Table for printing expressions.  */
 
     const struct op_print *la_op_print_tab;
@@ -567,6 +562,11 @@ struct language_defn : language_data
 
   virtual const struct lang_varobj_ops *varobj_ops () const;
 
+  /* Definitions related to expression printing, prefixifying, and
+     dumping.  */
+
+  virtual const struct exp_descriptor *expression_ops () const;
+
 protected:
 
   /* This is the overridable part of the GET_SYMBOL_NAME_MATCHER method.

gdb/m2-lang.c

@@ -199,7 +199,6 @@ const struct exp_descriptor exp_descriptor_modula2 =
 
 extern const struct language_data m2_language_data =
 {
-  &exp_descriptor_modula2,
   m2_op_print_tab,		/* expression operators for printing */
 };
 
@@ -444,6 +443,11 @@ public:
 
   bool range_checking_on_by_default () const override
   { return true; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_modula2; }
 };
 
 /* Single instance of the M2 language.  */

gdb/objc-lang.c

@@ -323,7 +323,6 @@ static const struct op_print objc_op_print_tab[] =
 
 extern const struct language_data objc_language_data =
 {
-  &exp_descriptor_standard,
   objc_op_print_tab,		/* Expression operators for printing */
 };
 

gdb/opencl-lang.c

@@ -1006,7 +1006,6 @@ const struct exp_descriptor exp_descriptor_opencl =
 /* Constant data representing the OpenCL language.  */
 extern const struct language_data opencl_language_data =
 {
-  &exp_descriptor_opencl,
   c_op_print_tab,		/* expression operators for printing */
 };
 
@@ -1070,6 +1069,11 @@ public:
 
   enum macro_expansion macro_expansion () const override
   { return macro_expansion_c; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_opencl; }
 };
 
 /* Single instance of the OpenCL language class.  */

gdb/p-lang.c

@@ -252,7 +252,6 @@ enum pascal_primitive_types {
 
 extern const struct language_data pascal_language_data =
 {
-  &exp_descriptor_standard,
   pascal_op_print_tab,		/* expression operators for printing */
 };
 

gdb/parse.c

@@ -762,8 +762,8 @@ void
 operator_length (const struct expression *expr, int endpos, int *oplenp,
 		 int *argsp)
 {
-  expr->language_defn->la_exp_desc->operator_length (expr, endpos,
+  expr->language_defn->expression_ops ()->operator_length (expr, endpos,
-						     oplenp, argsp);
+							   oplenp, argsp);
 }
 
 /* Default value for operator_length in exp_descriptor vectors.  */
@@ -1374,8 +1374,9 @@ exp_iterate (struct expression *exp,
       gdb_assert (oplen > 0);
 
       pos = endpos - oplen;
-      if (exp->language_defn->la_exp_desc->operator_check (exp, pos,
+      if (exp->language_defn->expression_ops ()->operator_check (exp, pos,
-							   objfile_func, data))
+								 objfile_func,
+								 data))
 	return 1;
 
       endpos = pos;

gdb/rust-lang.c

@@ -1901,7 +1901,6 @@ static const struct exp_descriptor exp_descriptor_rust =
 
 extern const struct language_data rust_language_data =
 {
-  &exp_descriptor_rust,
   c_op_print_tab,		/* expression operators for printing */
 };
 
@@ -2149,6 +2148,11 @@ public:
 
   bool range_checking_on_by_default () const override
   { return true; }
+
+  /* See language.h.  */
+
+  const struct exp_descriptor *expression_ops () const override
+  { return &exp_descriptor_rust; }
 };
 
 /* Single instance of the Rust language class.  */