Remove dump_prefix_expression

Since the expression rewrite, dump_prefix_expression has been
misnamed.  This patch cleans this up by removing the function, turning
it into a method on struct expression.

gdb/expprint.c

@@ -59,12 +59,6 @@ op_name (enum exp_opcode opcode)
     }
 }
 
-void
-dump_prefix_expression (struct expression *exp, struct ui_file *stream)
-{
-  exp->op->dump (stream, 0);
-}
-
 /* Meant to be used in debug sessions, so don't export it in a header file.  */
 extern void ATTRIBUTE_USED debug_exp (struct expression *exp);
 

gdb/expression.h

@@ -208,6 +208,12 @@ struct expression
     return op->opcode ();
   }
 
+  /* Dump the expression to STREAM.  */
+  void dump (struct ui_file *stream)
+  {
+    op->dump (stream, 0);
+  }
+
   /* Evaluate the expression.  EXPECT_TYPE is the context type of the
      expression; normally this should be nullptr.  NOSIDE controls how
      evaluation is performed.  */
@@ -277,8 +283,6 @@ extern struct value *evaluate_subexp_do_call (expression *exp,
 
 extern const char *op_name (enum exp_opcode opcode);
 
-extern void dump_prefix_expression (struct expression *, struct ui_file *);
-
 /* In an OP_RANGE expression, either bound could be empty, indicating
    that its value is by default that of the corresponding bound of the
    array or string.  Also, the upper end of the range can be exclusive

gdb/parse.c

@@ -527,7 +527,7 @@ parse_exp_in_context (const char **stringptr, CORE_ADDR pc,
   result->op->set_outermost ();
 
   if (expressiondebug)
-    dump_prefix_expression (result.get (), gdb_stdlog);
+    result->dump (gdb_stdlog);
 
   if (completer != nullptr)
     *completer = std::move (ps.m_completion_state);

gdb/stap-probe.c

@@ -1328,7 +1328,7 @@ stap_probe::parse_arguments (struct gdbarch *gdbarch)
       expression_up expr = stap_parse_argument (&cur, atype, gdbarch);
 
       if (stap_expression_debug)
-	dump_prefix_expression (expr.get (), gdb_stdlog);
+	expr->dump (gdb_stdlog);
 
       m_parsed_args.emplace_back (bitness, atype, std::move (expr));