From 3c437874e208b50bb35f07ca7683817431f1e01e Mon Sep 17 00:00:00 2001
From: Maciej Suminski <maciej.suminski@cern.ch>
Date: Tue, 9 Jun 2015 10:59:33 +0200
Subject: [PATCH] vhdlpp: Allow initializers for variables.

---
 vhdlpp/parse.y    | 14 ++++++++++----
 vhdlpp/vsignal.cc |  8 +++++++-
 vhdlpp/vsignal.h  |  6 +++---
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/vhdlpp/parse.y b/vhdlpp/parse.y
index 39061ffbb..29512b178 100644
--- a/vhdlpp/parse.y
+++ b/vhdlpp/parse.y
@@ -331,8 +331,8 @@ static void touchup_interface_for_functions(std::list<InterfacePort*>*ports)
 %type <expr> expression_logical_xnor expression_logical_xor
 %type <expr> name prefix selected_name
 %type <expr> shift_expression signal_declaration_assign_opt
-%type <expr> simple_expression simple_expression_2 term waveform_element
-%type <expr> interface_element_expression
+%type <expr> simple_expression simple_expression_2 term
+%type <expr> variable_declaration_assign_opt waveform_element interface_element_expression
 
 %type <expr_list> waveform waveform_elements
 %type <expr_list> name_list expression_list
@@ -2661,11 +2661,12 @@ variable_assignment
   ;
 
 variable_declaration /* IEEE 1076-2008 P6.4.2.4 */
-  : K_shared_opt K_variable identifier_list ':' subtype_indication ';'
+  : K_shared_opt K_variable identifier_list ':' subtype_indication
+    variable_declaration_assign_opt ';'
       { /* Save the signal declaration in the block_signals map. */
 	for (std::list<perm_string>::iterator cur = $3->begin()
 		   ; cur != $3->end() ; ++cur) {
-	      Variable*sig = new Variable(*cur, $5);
+	      Variable*sig = new Variable(*cur, $5, $6);
 	      FILE_NAME(sig, @2);
 	      active_scope->bind_name(*cur, sig);
 	}
@@ -2677,6 +2678,11 @@ variable_declaration /* IEEE 1076-2008 P6.4.2.4 */
       }
   ;
 
+variable_declaration_assign_opt
+  : VASSIGN expression { $$ = $2; }
+  |                    { $$ = 0;  }
+  ;
+
 wait_statement
   : K_wait K_for expression ';'
       { WaitForStmt*tmp = new WaitForStmt($3);
diff --git a/vhdlpp/vsignal.cc b/vhdlpp/vsignal.cc
index 043c2b1a9..38516dbaf 100644
--- a/vhdlpp/vsignal.cc
+++ b/vhdlpp/vsignal.cc
@@ -66,7 +66,7 @@ int Signal::emit(ostream&out, Entity*ent, ScopeBase*scope)
       return errors;
 }
 
-int Variable::emit(ostream&out, Entity*, ScopeBase*)
+int Variable::emit(ostream&out, Entity*ent, ScopeBase*scope)
 {
       int errors = 0;
 
@@ -75,6 +75,12 @@ int Variable::emit(ostream&out, Entity*, ScopeBase*)
       if (peek_refcnt_sequ_() > 0 || !peek_type()->can_be_packed())
 	    decl.reg_flag = true;
       errors += decl.emit(out, peek_name());
+
+      Expression*init_expr = peek_init_expr();
+      if (init_expr) {
+	    out << " = ";
+	    init_expr->emit(out, ent, scope);
+      }
       out << ";" << endl;
       return errors;
 }
diff --git a/vhdlpp/vsignal.h b/vhdlpp/vsignal.h
index d2bfdbcd0..6aa225d14 100644
--- a/vhdlpp/vsignal.h
+++ b/vhdlpp/vsignal.h
@@ -77,7 +77,7 @@ class Signal : public SigVarBase {
 class Variable : public SigVarBase {
 
     public:
-      Variable(perm_string name, const VType*type);
+      Variable(perm_string name, const VType*type, Expression*init_expr = NULL);
 
       int emit(ostream&out, Entity*ent, ScopeBase*scope);
       void write_to_stream(std::ostream&fd);
@@ -93,8 +93,8 @@ inline Signal::Signal(perm_string name, const VType*type, Expression*init_expr)
 {
 }
 
-inline Variable::Variable(perm_string name, const VType*type)
-: SigVarBase(name, type, 0)
+inline Variable::Variable(perm_string name, const VType*type, Expression*init_expr)
+: SigVarBase(name, type, init_expr)
 {
 }