Implement the ivl_target ivl_scope_child functions.

These are a more convenient way of iterating through child scopes.

ivl.def

@@ -197,6 +197,8 @@ ivl_scope_attr_cnt
 ivl_scope_attr_val
 ivl_scope_basename
 ivl_scope_children
+ivl_scope_child
+ivl_scope_childs
 ivl_scope_class
 ivl_scope_classes
 ivl_scope_def

ivl_target.h

@@ -20,6 +20,7 @@
  */
 
 # include  <inttypes.h>
+# include  <stddef.h>
 
 /* Re the _CLASS define: clang++ wants this to be class to match the
  * definition, but clang (the C) compiler needs it to be a struct
@@ -1678,6 +1679,11 @@ extern unsigned    ivl_parameter_lineno(ivl_parameter_t net);
  *    If the scope has no children, this method will return 0 and
  *    otherwise do nothing.
  *
+ * ivl_scope_childs
+ * ivl_scope_child
+ *    This is an alternative way of getting at the childs scopes of a
+ *    given scope.
+ *
  * ivl_scope_def
  *    Task definition scopes carry a task definition, in the form of
  *    a statement. This method accesses that definition. The
@@ -1779,6 +1785,8 @@ extern ivl_statement_t ivl_scope_def(ivl_scope_t net);
 extern const char* ivl_scope_def_file(ivl_scope_t net);
 extern unsigned ivl_scope_def_lineno(ivl_scope_t net);
 
+extern size_t      ivl_scope_childs(ivl_scope_t net);
+extern ivl_scope_t ivl_scope_child(ivl_scope_t net, size_t idx);
 extern unsigned   ivl_scope_classes(ivl_scope_t net);
 extern ivl_type_t ivl_scope_class(ivl_scope_t net, unsigned idx);
 extern unsigned       ivl_scope_enumerates(ivl_scope_t net);

t-dll-api.cc

@@ -1919,6 +1919,18 @@ extern "C" int ivl_scope_children(ivl_scope_t net,
       return 0;
 }
 
+extern "C" size_t ivl_scope_childs(ivl_scope_t net)
+{
+      assert(net->child.size() == net->children.size());
+      return net->child.size();
+}
+
+extern "C" ivl_scope_t ivl_scope_child(ivl_scope_t net, size_t idx)
+{
+      assert(net && idx < net->child.size());
+      return net->child[idx];
+}
+
 extern "C" ivl_type_t ivl_scope_class(ivl_scope_t net, unsigned idx)
 {
       assert(idx < net->classes.size());

t-dll.cc

@@ -2363,6 +2363,7 @@ void dll_target::scope(const NetScope*net)
 	    scop->parent = find_scope(des_, net->parent());
 	    assert(scop->parent);
 	    scop->parent->children[net->fullname()] = scop;
+	    scop->parent->child .push_back(scop);
 	    scop->nlog_ = 0;
 	    scop->log_ = 0;
 	    scop->nevent_ = 0;

t-dll.h

@@ -639,6 +639,9 @@ struct ivl_process_s {
 struct ivl_scope_s {
       ivl_scope_t parent;
       std::map<hname_t,ivl_scope_t> children;
+	// This is just like the children map above, but in vector
+	// form for convenient access.
+      std::vector<ivl_scope_t> child;
 
       perm_string name_;
       perm_string tname_;