gdb: Convert la_name_of_this to a method

Convert language_data::la_name_of_this member variable to a virtual
method language_defn::name_of_this.

There should be no user visible changes after this commit.

gdb/ChangeLog:

	* ada-lang.c (ada_language_data): Remove la_name_of_this
	initializer.
	* ax-gdb.c (gen_expr): Update call to name_of_this.
	* c-exp.y (classify_name): Likewise.
	* c-lang.c (c_language_data): Remove la_name_of_this initializer.
	(cplus_language_data): Likewise.
	(cplus_language::name_of_this): New member function.
	(asm_language_data): Remove la_name_of_this initializer.
	(minimal_language_data): Likewise.
	* d-lang.c (d_language_data): Likewise.
	(d_language::name_of_this): New member function.
	* expprint.c (print_subexp_standard): Update call to name_of_this.
	* f-lang.c (f_language_data): Remove la_name_of_this initializer.
	* go-lang.c (go_language_data): Likewise.
	* language.c (unknown_language_data): Likewise.
	(unknown_language::name_of_this): New member function.
	(auto_language_data): Remove la_name_of_this initializer.
	(auto_language::name_of_this): New member function.
	* language.h (language_data): Delete la_name_of_this member
	variable.
	(language_defn::name_of_this): New member function.
	* m2-lang.c (m2_language_data): Remove la_name_of_this
	initializer.
	* objc-lang.c (objc_language_data): Likewise.
	(objc_language::name_of_this): New member function.
	* opencl-lang.c (opencl_language_data): Remove la_name_of_this
	initializer.
	* p-lang.c (pascal_language_data): Likewise.
	(pascal_language::name_of_this): New member function.
	* rust-lang.c (rust_language_data): Remove la_name_of_this
	initializer.
	* symtab.c (lookup_language_this): Update call to name_of_this.
	(lookup_symbol_aux): Likewise.
	* valops.c (value_of_this): Likewise.

gdb/ChangeLog

@@ -1,3 +1,40 @@
+2020-09-16  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* ada-lang.c (ada_language_data): Remove la_name_of_this
+	initializer.
+	* ax-gdb.c (gen_expr): Update call to name_of_this.
+	* c-exp.y (classify_name): Likewise.
+	* c-lang.c (c_language_data): Remove la_name_of_this initializer.
+	(cplus_language_data): Likewise.
+	(cplus_language::name_of_this): New member function.
+	(asm_language_data): Remove la_name_of_this initializer.
+	(minimal_language_data): Likewise.
+	* d-lang.c (d_language_data): Likewise.
+	(d_language::name_of_this): New member function.
+	* expprint.c (print_subexp_standard): Update call to name_of_this.
+	* f-lang.c (f_language_data): Remove la_name_of_this initializer.
+	* go-lang.c (go_language_data): Likewise.
+	* language.c (unknown_language_data): Likewise.
+	(unknown_language::name_of_this): New member function.
+	(auto_language_data): Remove la_name_of_this initializer.
+	(auto_language::name_of_this): New member function.
+	* language.h (language_data): Delete la_name_of_this member
+	variable.
+	(language_defn::name_of_this): New member function.
+	* m2-lang.c (m2_language_data): Remove la_name_of_this
+	initializer.
+	* objc-lang.c (objc_language_data): Likewise.
+	(objc_language::name_of_this): New member function.
+	* opencl-lang.c (opencl_language_data): Remove la_name_of_this
+	initializer.
+	* p-lang.c (pascal_language_data): Likewise.
+	(pascal_language::name_of_this): New member function.
+	* rust-lang.c (rust_language_data): Remove la_name_of_this
+	initializer.
+	* symtab.c (lookup_language_this): Update call to name_of_this.
+	(lookup_symbol_aux): Likewise.
+	* valops.c (value_of_this): Likewise.
+
 2020-09-16  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* ada-lang.c (ada_language_data): Remove

gdb/ada-lang.c

@@ -13723,7 +13723,6 @@ extern const struct language_data ada_language_data =
   macro_expansion_no,
   ada_extensions,
   &ada_exp_descriptor,
-  NULL,                         /* name_of_this */
   true,                         /* la_store_sym_names_in_linkage_form_p */
   ada_op_print_tab,             /* expression operators for printing */
   0,                            /* c-style arrays */

gdb/ax-gdb.c

@@ -2233,7 +2233,7 @@ gen_expr (struct expression *exp, union exp_element **pc,
 
 	sym = lookup_language_this (lang, b).symbol;
 	if (!sym)
-	  error (_("no `%s' found"), lang->la_name_of_this);
+	  error (_("no `%s' found"), lang->name_of_this ());
 
 	gen_var_ref (ax, value, sym);
 

gdb/c-exp.y

@@ -3036,7 +3036,7 @@ classify_name (struct parser_state *par_state, const struct block *block,
   memset (&is_a_field_of_this, 0, sizeof (is_a_field_of_this));
 
   bsym = lookup_symbol (copy.c_str (), block, VAR_DOMAIN,
-			par_state->language ()->la_name_of_this
+			par_state->language ()->name_of_this ()
 			? &is_a_field_of_this : NULL);
 
   if (bsym.symbol && SYMBOL_CLASS (bsym.symbol) == LOC_BLOCK)

gdb/c-lang.c

@@ -889,7 +889,6 @@ extern const struct language_data c_language_data =
   macro_expansion_c,
   c_extensions,
   &exp_descriptor_c,
-  NULL,				/* name_of_this */
   true,				/* la_store_sym_names_in_linkage_form_p */
   c_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */
@@ -989,7 +988,6 @@ extern const struct language_data cplus_language_data =
   macro_expansion_c,
   cplus_extensions,
   &exp_descriptor_c,
-  "this",                       /* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   c_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */
@@ -1153,6 +1151,11 @@ public:
     return cp_lookup_symbol_nonlocal (this, name, block, domain);
   }
 
+  /* See language.h.  */
+
+  const char *name_of_this () const override
+  { return "this"; }
+
 protected:
 
   /* See language.h.  */
@@ -1186,7 +1189,6 @@ extern const struct language_data asm_language_data =
   macro_expansion_c,
   asm_extensions,
   &exp_descriptor_c,
-  NULL,				/* name_of_this */
   true,				/* la_store_sym_names_in_linkage_form_p */
   c_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */
@@ -1241,7 +1243,6 @@ extern const struct language_data minimal_language_data =
   macro_expansion_c,
   NULL,
   &exp_descriptor_c,
-  NULL,				/* name_of_this */
   true,				/* la_store_sym_names_in_linkage_form_p */
   c_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */

gdb/d-lang.c

@@ -142,7 +142,6 @@ extern const struct language_data d_language_data =
   macro_expansion_no,
   d_extensions,
   &exp_descriptor_c,
-  "this",
   false,			/* la_store_sym_names_in_linkage_form_p */
   d_op_print_tab,		/* Expression operators for printing.  */
   1,				/* C-style arrays.  */
@@ -271,6 +270,11 @@ public:
   {
     return d_parse (ps);
   }
+
+  /* See language.h.  */
+
+  const char *name_of_this () const override
+  { return "this"; }
 };
 
 /* Single instance of the D language class.  */

gdb/expprint.c

@@ -504,8 +504,8 @@ print_subexp_standard (struct expression *exp, int *pos,
 
     case OP_THIS:
       ++(*pos);
-      if (exp->language_defn->la_name_of_this)
+      if (exp->language_defn->name_of_this () != NULL)
-	fputs_filtered (exp->language_defn->la_name_of_this, stream);
+	fputs_filtered (exp->language_defn->name_of_this (), stream);
       else
 	fprintf_styled (stream, metadata_style.style (),
 			_("<language %s has no 'this'>"),

gdb/f-lang.c

@@ -502,7 +502,6 @@ extern const struct language_data f_language_data =
   macro_expansion_no,
   f_extensions,
   &exp_descriptor_f,
-  NULL,                    	/* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   f_op_print_tab,		/* expression operators for printing */
   0,				/* arrays are first-class (not c-style) */

gdb/go-lang.c

@@ -517,7 +517,6 @@ extern const struct language_data go_language_data =
   macro_expansion_no,
   NULL,
   &exp_descriptor_c,
-  NULL,				/* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   go_op_print_tab,		/* Expression operators for printing.  */
   1,				/* C-style arrays.  */

gdb/language.c

@@ -792,7 +792,6 @@ extern const struct language_data unknown_language_data =
   macro_expansion_no,
   NULL,
   &exp_descriptor_standard,
-  "this",        	    	/* name_of_this */
   true,				/* store_sym_names_in_linkage_form_p */
   unk_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */
@@ -898,6 +897,11 @@ public:
   {
     return default_is_string_type_p (type);
   }
+
+  /* See language.h.  */
+
+  const char *name_of_this () const override
+  { return "this"; }
 };
 
 /* Single instance of the unknown language class.  */
@@ -917,7 +921,6 @@ extern const struct language_data auto_language_data =
   macro_expansion_no,
   NULL,
   &exp_descriptor_standard,
-  "this",		        /* name_of_this */
   false,			/* store_sym_names_in_linkage_form_p */
   unk_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */
@@ -1023,6 +1026,11 @@ public:
   {
     return default_is_string_type_p (type);
   }
+
+  /* See language.h.  */
+
+  const char *name_of_this () const override
+  { return "this"; }
 };
 
 /* Single instance of the fake "auto" language.  */

gdb/language.h

@@ -227,11 +227,6 @@ struct language_data
 
     /* Now come some hooks for lookup_symbol.  */
 
-    /* If this is non-NULL, specifies the name that of the implicit
-       local variable that refers to the current object instance.  */
-
-    const char *la_name_of_this;
-
     /* True if the symbols names should be stored in GDB's data structures
        for minimal/partial/full symbols using their linkage (aka mangled)
        form; false if the symbol names should be demangled first.
@@ -557,6 +552,14 @@ struct language_defn : language_data
   virtual const char *struct_too_deep_ellipsis () const
   { return "{...}"; }
 
+  /* If this returns non-NULL then the string returned specifies the name
+     of the implicit local variable that refers to the current object
+     instance.  Return NULL (the default) for languages that have no name
+     for the current object instance.  */
+
+  virtual const char *name_of_this () const
+  { return nullptr; }
+
 protected:
 
   /* This is the overridable part of the GET_SYMBOL_NAME_MATCHER method.

gdb/m2-lang.c

@@ -208,7 +208,6 @@ extern const struct language_data m2_language_data =
   macro_expansion_no,
   NULL,
   &exp_descriptor_modula2,
-  NULL,		                /* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   m2_op_print_tab,		/* expression operators for printing */
   0,				/* arrays are first-class (not c-style) */

gdb/objc-lang.c

@@ -337,7 +337,6 @@ extern const struct language_data objc_language_data =
   macro_expansion_c,
   objc_extensions,
   &exp_descriptor_standard,
-  "self",		        /* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   objc_op_print_tab,		/* Expression operators for printing */
   1,				/* C-style arrays */
@@ -418,6 +417,11 @@ public:
 
     return real_stop_pc;
   }
+
+  /* See language.h.  */
+
+  const char *name_of_this () const override
+  { return "self"; }
 };
 
 /* Single instance of the class representing the Objective-C language.  */

gdb/opencl-lang.c

@@ -1015,7 +1015,6 @@ extern const struct language_data opencl_language_data =
   macro_expansion_c,
   NULL,
   &exp_descriptor_opencl,
-  NULL,                         /* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   c_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */

gdb/p-lang.c

@@ -266,7 +266,6 @@ extern const struct language_data pascal_language_data =
   macro_expansion_no,
   p_extensions,
   &exp_descriptor_standard,
-  "this",		        /* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   pascal_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */
@@ -497,6 +496,11 @@ public:
     return is_pascal_string_type (type, nullptr, nullptr, nullptr,
 				  nullptr, nullptr) > 0;
   }
+
+  /* See language.h.  */
+
+  const char *name_of_this () const override
+  { return "this"; }
 };
 
 /* Single instance of the Pascal language class.  */

gdb/rust-lang.c

@@ -1915,7 +1915,6 @@ extern const struct language_data rust_language_data =
   macro_expansion_no,
   rust_extensions,
   &exp_descriptor_rust,
-  NULL,				/* name_of_this */
   false,			/* la_store_sym_names_in_linkage_form_p */
   c_op_print_tab,		/* expression operators for printing */
   1,				/* c-style arrays */

gdb/symtab.c

@@ -1912,7 +1912,7 @@ struct block_symbol
 lookup_language_this (const struct language_defn *lang,
 		      const struct block *block)
 {
-  if (lang->la_name_of_this == NULL || block == NULL)
+  if (lang->name_of_this () == NULL || block == NULL)
     return {};
 
   if (symbol_lookup_debug > 1)
@@ -1929,7 +1929,7 @@ lookup_language_this (const struct language_defn *lang,
     {
       struct symbol *sym;
 
-      sym = block_lookup_symbol (block, lang->la_name_of_this,
+      sym = block_lookup_symbol (block, lang->name_of_this (),
 				 symbol_name_match_type::SEARCH_NAME,
 				 VAR_DOMAIN);
       if (sym != NULL)
@@ -2069,7 +2069,7 @@ lookup_symbol_aux (const char *name, symbol_name_match_type match_type,
 	  if (t->code () != TYPE_CODE_STRUCT
 	      && t->code () != TYPE_CODE_UNION)
 	    error (_("Internal error: `%s' is not an aggregate"),
-		   langdef->la_name_of_this);
+		   langdef->name_of_this ());
 
 	  if (check_field (t, name, is_a_field_of_this))
 	    {

gdb/valops.c

@@ -3716,7 +3716,7 @@ value_of_this (const struct language_defn *lang)
   const struct block *b;
   struct frame_info *frame;
 
-  if (!lang->la_name_of_this)
+  if (lang->name_of_this () == NULL)
     error (_("no `this' in current language"));
 
   frame = get_selected_frame (_("no frame selected"));
@@ -3726,7 +3726,7 @@ value_of_this (const struct language_defn *lang)
   sym = lookup_language_this (lang, b);
   if (sym.symbol == NULL)
     error (_("current stack frame does not contain a variable named `%s'"),
-	   lang->la_name_of_this);
+	   lang->name_of_this ());
 
   return read_var_value (sym.symbol, sym.block, frame);
 }