Unify no-component assertions on target variables

There are several tapsets that can't deal with component dereferences on
their target variables, and they all check-and-throw in the same way.
This refactors the checks into a target_symbol member.

* staptree.cxx (target_symbol::assert_no_components): New.
* tapsets.cxx (tracepoint_var_expanding_visitor::visit_target_symbol_arg,
  tracepoint_var_expanding_visitor::visit_target_symbol_context): Use
  the new assertion function to check for no components.
* tapset-mark.cxx (mark_var_expanding_visitor::visit_target_symbol_arg,
  mark_var_expanding_visitor::visit_target_symbol_context): Ditto.
* tapset-perfmon.cxx (perfmon_var_expanding_visitor::visit_target_symbol): Ditto.
* tapset-procfs.cxx (procfs_var_expanding_visitor::visit_target_symbol): Ditto.
* tapset-utrace.cxx (utrace_var_expanding_visitor::visit_target_symbol_arg,
  utrace_var_expanding_visitor::visit_target_symbol_context): Ditto.

1 files changed, 24 insertions, 0 deletions

diff --git a/staptree.cxx b/staptree.cxx
index 1231f74d..321650eb 100644
--- a/staptree.cxx
+++ b/staptree.cxx
@@ -186,6 +186,30 @@ operator << (ostream& o, const exp_type& e)
 }
 
 
+void
+target_symbol::assert_no_components(const std::string& tapset)
+{
+  if (components.empty())
+    return;
+
+  switch (components[0].type)
+    {
+    case target_symbol::comp_literal_array_index:
+      throw semantic_error(tapset + " variable '" + base_name +
+                           "' may not be used as array",
+                           components[0].tok);
+    case target_symbol::comp_struct_member:
+      throw semantic_error(tapset + " variable '" + base_name +
+                           "' may not be used as a structure",
+                           components[0].tok);
+    default:
+      throw semantic_error ("invalid use of " + tapset +
+                            " variable '" + base_name + "'",
+                            components[0].tok);
+    }
+}
+
+
 // ------------------------------------------------------------------------
 // parse tree printing