diff --git a/tgt-vhdl/expr.cc b/tgt-vhdl/expr.cc
index 07cd703cb..447857bf6 100644
--- a/tgt-vhdl/expr.cc
+++ b/tgt-vhdl/expr.cc
@@ -218,6 +218,29 @@ static vhdl_expr *translate_select(ivl_expr_t e)
    return from->resize(ivl_expr_width(e));
 }
 
+static vhdl_type *expr_to_vhdl_type(ivl_expr_t e)
+{
+   if (ivl_expr_signed(e))
+      return vhdl_type::nsigned(ivl_expr_width(e));
+   else
+      return vhdl_type::nunsigned(ivl_expr_width(e));
+}
+
+template <class T>
+static T *translate_parms(T *t, ivl_expr_t e)
+{
+   int nparams = ivl_expr_parms(e);
+   for (int i = 0; i < nparams; i++) {
+      vhdl_expr *param = translate_expr(ivl_expr_parm(e, i));
+      if (NULL == param)
+         return NULL;
+
+      t->add_expr(param);
+   }
+
+   return t;
+}
+
 static vhdl_expr *translate_ufunc(ivl_expr_t e)
 {
    ivl_scope_t defscope = ivl_expr_def(e);
@@ -232,24 +255,10 @@ static vhdl_expr *translate_ufunc(ivl_expr_t e)
 
    const char *funcname = ivl_scope_tname(defscope);
 
-   vhdl_type *rettype;
-   if (ivl_expr_signed(e))
-      rettype = vhdl_type::nsigned(ivl_expr_width(e));
-   else
-      rettype = vhdl_type::nunsigned(ivl_expr_width(e));
-   
+   vhdl_type *rettype = expr_to_vhdl_type(e);
    vhdl_fcall *fcall = new vhdl_fcall(funcname, rettype);
 
-   int nparams = ivl_expr_parms(e);
-   for (int i = 0; i < nparams; i++) {
-      vhdl_expr *param = translate_expr(ivl_expr_parm(e, i));
-      if (NULL == param)
-         return NULL;
-
-      fcall->add_expr(param);
-   }
-
-   return fcall;
+   return translate_parms<vhdl_fcall>(fcall, e);
 }
 
 static vhdl_expr *translate_ternary(ivl_expr_t e)
@@ -259,6 +268,14 @@ static vhdl_expr *translate_ternary(ivl_expr_t e)
    return NULL;
 }
 
+static vhdl_expr *translate_concat(ivl_expr_t e)
+{
+   vhdl_type *rtype = expr_to_vhdl_type(e);
+   vhdl_binop_expr *concat = new vhdl_binop_expr(VHDL_BINOP_CONCAT, rtype);
+
+   return translate_parms<vhdl_binop_expr>(concat, e);
+}
+
 /*
  * Generate a VHDL expression from a Verilog expression.
  */
@@ -284,6 +301,8 @@ vhdl_expr *translate_expr(ivl_expr_t e)
       return translate_ufunc(e);
    case IVL_EX_TERNARY:
       return translate_ternary(e);
+   case IVL_EX_CONCAT:
+      return translate_concat(e);
    default:
       error("No VHDL translation for expression at %s:%d (type = %d)",
             ivl_expr_file(e), ivl_expr_lineno(e), type);
diff --git a/tgt-vhdl/scope.cc b/tgt-vhdl/scope.cc
index 0d6b8dd88..da0375d95 100644
--- a/tgt-vhdl/scope.cc
+++ b/tgt-vhdl/scope.cc
@@ -185,7 +185,7 @@ static std::string make_safe_name(ivl_signal_t sig)
    
    const char *vhdl_reserved[] = {
       "in", "out", "entity", "architecture", "inout", "array",
-      "is", "not", "and", "or", "bus", "bit", // Etc...
+      "is", "not", "and", "or", "bus", "bit", "line", // Etc...
       NULL
    };
    for (const char **p = vhdl_reserved; *p != NULL; p++) {
@@ -354,16 +354,16 @@ static void map_signal(ivl_signal_t to, vhdl_entity *parent,
    // result of the expression and that is mapped to the port
    // This is actually a bit stricter than necessary: but turns out
    // to be much easier to implement
-   const char *basename = ivl_signal_basename(to);
+   std::string name = make_safe_name(to);
    vhdl_var_ref *to_ref;
    if ((to_ref = dynamic_cast<vhdl_var_ref*>(to_e))) {
-      inst->map_port(basename, to_ref);
+      inst->map_port(name.c_str(), to_ref);
    }
    else {
       // Not a static expression
       std::string tmpname(inst->get_inst_name().c_str());
       tmpname += "_";
-      tmpname += basename;
+      tmpname += name;
       tmpname += "_Expr";
       
       vhdl_type *tmptype = new vhdl_type(*to_e->get_type());
@@ -374,7 +374,7 @@ static void map_signal(ivl_signal_t to, vhdl_entity *parent,
       parent->get_arch()->add_stmt(new vhdl_cassign_stmt(tmp_ref1, to_e));
 
       vhdl_var_ref *tmp_ref2 = new vhdl_var_ref(*tmp_ref1);
-      inst->map_port(basename, tmp_ref2);
+      inst->map_port(name.c_str(), tmp_ref2);
    }
 }
 
diff --git a/tgt-vhdl/vhdl_syntax.cc b/tgt-vhdl/vhdl_syntax.cc
index 764898033..d4773fa97 100644
--- a/tgt-vhdl/vhdl_syntax.cc
+++ b/tgt-vhdl/vhdl_syntax.cc
@@ -705,7 +705,7 @@ void vhdl_binop_expr::emit(std::ostream &of, int level) const
    while (++it != operands_.end()) {
       const char* ops[] = {
          "and", "or", "=", "/=", "+", "-", "*", "<",
-         ">", "sll", "srl", "xor"
+         ">", "sll", "srl", "xor", "&"
       };
 
       of << " " << ops[op_] << " ";
diff --git a/tgt-vhdl/vhdl_syntax.hh b/tgt-vhdl/vhdl_syntax.hh
index c87eea284..c45351d18 100644
--- a/tgt-vhdl/vhdl_syntax.hh
+++ b/tgt-vhdl/vhdl_syntax.hh
@@ -76,6 +76,7 @@ enum vhdl_binop_t {
    VHDL_BINOP_SL,
    VHDL_BINOP_SR,
    VHDL_BINOP_XOR,
+   VHDL_BINOP_CONCAT,
 };
 
 /*