Partial fix for br956 (various enumeration bugs)

This patch fixes the following enumeration bugs:

When looking for an enumeration look in the current scope and then
recursively in any parent scope.

Add enumeration definitions to a package scope.

elab_scope.cc

@@ -687,6 +687,7 @@ bool PPackage::elaborate_scope(Design*des, NetScope*scope)
 
       collect_scope_parameters_(des, scope, parameters);
       collect_scope_localparams_(des, scope, localparams);
+      elaborate_scope_enumerations(des, scope, enum_sets);
       elaborate_scope_funcs(des, scope, funcs);
       elaborate_scope_tasks(des, scope, tasks);
       return true;

elab_sig.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2013 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2014 Stephen Williams (steve@icarus.com)
  * Copyright CERN 2012 / Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
@@ -1249,7 +1249,7 @@ NetNet* PWire::elaborate_sig(Design*des, NetScope*scope) const
 
       } else if (enum_type_t*enum_type = dynamic_cast<enum_type_t*>(set_data_type_)) {
 	    list<named_pexpr_t>::const_iterator sample_name = enum_type->names->begin();
-	    const netenum_t*use_enum = scope->enumeration_for_name(sample_name->name);
+	    const netenum_t*use_enum = scope->find_enumeration_for_name(sample_name->name);
 
 	    if (debug_elaborate) {
 		  cerr << get_fileline() << ": debug: Create signal " << wtype

net_scope.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2013 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2014 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -189,6 +189,22 @@ void NetScope::set_line(perm_string file, perm_string def_file,
       def_lineno_ = def_lineno;
 }
 
+/*
+ * Look for the enumeration in the current scope and any parent scopes.
+ */
+const netenum_t*NetScope::find_enumeration_for_name(perm_string name)
+{
+      NetScope *cur_scope = this;
+      while (cur_scope) {
+	    NetEConstEnum*tmp = cur_scope->enum_names_[name];
+	    if (tmp) break;
+	    cur_scope = cur_scope->parent();
+      }
+
+      assert(cur_scope);
+      return cur_scope->enum_names_[name]->enumeration();
+}
+
 void NetScope::set_parameter(perm_string key, bool is_annotatable,
 			     PExpr*val, ivl_variable_type_t type__,
 			     PExpr*msb, PExpr*lsb, bool signed_flag,

netlist.h

@@ -919,6 +919,10 @@ class NetScope : public Definitions, public Attrib {
 	   if a unique name couldn't be generated. */
       bool auto_name(const char* prefix, char pad, const char* suffix);
 
+	/* Routine to search for the enumeration given a name. It basically
+	 * does what enumeration_for_name() does but searched the hierarchy. */
+      const netenum_t*find_enumeration_for_name(perm_string name);
+
 	/* Parameters exist within a scope, and these methods allow
 	   one to manipulate the set. In these cases, the name is the
 	   *simple* name of the parameter, the hierarchy is implicit in