Chain class instance constructors with arguments.

PClass.cc

@@ -20,7 +20,7 @@
 # include  "PClass.h"
 
 PClass::PClass(perm_string name, LexicalScope*parent)
-: PScopeExtra(name, parent)
+: PScopeExtra(name, parent), type(0), chain(0)
 {
 }
 

PClass.h

@@ -24,6 +24,8 @@
 # include  "StringHeap.h"
 # include  <iostream>
 
+class PChainConstructor;
+
 /*
  * SystemVerilog supports class declarations with their own lexical
  * scope, etc. The parser arranges for these to be created and
@@ -40,6 +42,7 @@ class PClass : public PScopeExtra, public LineInfo {
 
     public:
       class_type_t*type;
+      PChainConstructor*chain;
 };
 
 #endif

PExpr.h

@@ -558,7 +558,8 @@ class PENewClass : public PExpr {
     private:
       NetExpr* elaborate_expr_constructor_(Design*des, NetScope*scope,
 					   const netclass_t*ctype,
-					   NetExpr*obj, unsigned flags) const;
+					   NetExpr*obj, unsigned flags,
+					   const netclass_t*derived) const;
 
     private:
       std::vector<PExpr*>parms_;

PFunction.cc

@@ -19,6 +19,7 @@
 
 # include "config.h"
 # include "PTask.h"
+# include "Statement.h"
 # include <cassert>
 
 PFunction::PFunction(perm_string name, LexicalScope*parent, bool is_auto__)
@@ -43,3 +44,17 @@ void PFunction::set_return(const data_type_t*t)
 {
       return_type_ = t;
 }
+
+PChainConstructor* PFunction::extract_chain_constructor()
+{
+      PChainConstructor*res = 0;
+
+      if (res = dynamic_cast<PChainConstructor*> (statement_)) {
+	    statement_ = 0;
+
+      } else if (PBlock*blk = dynamic_cast<PBlock*>(statement_)) {
+	    res = blk->extract_chain_constructor();
+      }
+
+      return res;
+}

PTask.h

@@ -29,6 +29,7 @@ class Design;
 class NetExpr;
 class NetNet;
 class NetScope;
+class PChainConstructor;
 class PWire;
 class Statement;
 class PExpr;
@@ -117,6 +118,11 @@ class PFunction : public PTaskFunc {
 
       inline Statement* get_statement() { return statement_; }
 
+	// This is only used if this function is a constructor. In
+	// that case, this method looks for a PChainConstructor in the
+	// statement and extracts it if found.
+      PChainConstructor*extract_chain_constructor();
+
       void elaborate_scope(Design*des, NetScope*scope) const;
 
 	/* elaborate the ports and return value. */

Statement.cc

@@ -115,6 +115,21 @@ PBlock::~PBlock()
 	    delete list_[idx];
 }
 
+PChainConstructor* PBlock::extract_chain_constructor()
+{
+      if (list_.empty())
+	    return 0;
+
+      if (PChainConstructor*res = dynamic_cast<PChainConstructor*> (list_[0])) {
+	    for (size_t idx = 0 ; idx < list_.size()-1 ; idx += 1)
+		  list_[idx] = list_[idx+1];
+	    list_.resize(list_.size()-1);
+	    return res;
+      }
+
+      return 0;
+}
+
 void PBlock::set_join_type(PBlock::BL_TYPE type)
 {
       assert(bl_type_ == BL_PAR);
@@ -206,6 +221,21 @@ PCAssign::~PCAssign()
       delete expr_;
 }
 
+PChainConstructor::PChainConstructor(const list<PExpr*>&parms)
+: parms_(parms.size())
+{
+      list<PExpr*>::const_iterator cur = parms.begin();
+      for (size_t idx = 0 ; idx < parms_.size() ; idx += 1) {
+	    parms_[idx] = *cur;
+	    ++cur;
+      }
+      assert(cur == parms.end());
+}
+
+PChainConstructor::~PChainConstructor()
+{
+}
+
 PCondit::PCondit(PExpr*ex, Statement*i, Statement*e)
 : expr_(ex), if_(i), else_(e)
 {

Statement.h

@@ -31,6 +31,7 @@
 # include  "HName.h"
 # include  "LineInfo.h"
 class PExpr;
+class PChainConstructor;
 class PPackage;
 class Statement;
 class PEventStatement;
@@ -181,6 +182,11 @@ class PBlock  : public PScope, public Statement {
 
       BL_TYPE bl_type() const { return bl_type_; }
 
+	// This is only used if this block is the statement list for a
+	// constructor. We look for a PChainConstructor as the first
+	// statement, and if it is there, extract it.
+      PChainConstructor*extract_chain_constructor();
+
 	// If the bl_type() is BL_PAR, it is possible to replace it
 	// with JOIN_NONE or JOIN_ANY. This is to help the parser.
       void set_join_type(BL_TYPE);
@@ -272,6 +278,25 @@ class PCAssign  : public Statement {
       PExpr*expr_;
 };
 
+/*
+ * This represents the syntax "super.new(...)". This is not really an
+ * executable statement, but the elaborator will handle these
+ * specially and will remove them from the statement stream. If any
+ */
+class PChainConstructor : public Statement {
+    public:
+      PChainConstructor(const list<PExpr*>&parms);
+      ~PChainConstructor();
+
+      virtual void dump(ostream&out, unsigned ind) const;
+
+      inline const std::vector<PExpr*>& chain_args(void) const
+      { return parms_; }
+
+    private:
+      std::vector<PExpr*> parms_;
+};
+
 class PCondit  : public Statement {
 
     public:

elab_expr.cc

@@ -4679,13 +4679,21 @@ unsigned PENewClass::test_width(Design*, NetScope*, width_mode_t&)
  * This elaborates the constructor for a class. This arranges for the
  * call of parent class constructors, if present, and also
  * initializers in front of an explicit constructor.
+ *
+ * The derived argument is the type of the class derived from the
+ * current one. This is used to get chained constructor arguments, if necessary.
  */
 NetExpr* PENewClass::elaborate_expr_constructor_(Design*des, NetScope*scope,
 						 const netclass_t*ctype,
-						 NetExpr*obj, unsigned flags) const
+						 NetExpr*obj, unsigned flags,
+						 const netclass_t*derived) const
 {
+	// If there is a super-class, then call the super-class
+	// constructors first. The results of the current class
+	// constructors cannot effect the superclass, so this is the
+	// right order of events.
       if (const netclass_t*super_class = ctype->get_super()) {
-	    obj = elaborate_expr_constructor_(des, scope, super_class, obj, flags);
+	    obj = elaborate_expr_constructor_(des, scope, super_class, obj, flags, ctype);
       }
 
 
@@ -4710,10 +4718,18 @@ NetExpr* PENewClass::elaborate_expr_constructor_(Design*des, NetScope*scope,
 	    obj = tmp;
       }
 
+	// The parameters for the constructor are the arguments of the
+	// new(...) expression, unless we are recursing, in which case
+	// we use the chained arguments. Note that the arguments to
+	// the chained constructor must be elaborated in the scope of
+	// the subclass (so that arguments can be passed down) so also
+	// select which scope we are going to use.
+      const vector<PExpr*>&use_parms = derived? derived->get_chain_args() : parms_;
+
       NetScope*new_scope = ctype->method_from_name(perm_string::literal("new"));
       if (new_scope == 0) {
 	      // No constructor.
-	    if (parms_.size() > 0) {
+	    if (use_parms.size() > 0) {
 		  cerr << get_fileline() << ": error: "
 		       << "Class " << ctype->get_name()
 		       << " has no constructor, but you passed " << parms_.size()
@@ -4730,9 +4746,9 @@ NetExpr* PENewClass::elaborate_expr_constructor_(Design*des, NetScope*scope,
 	// Are there too many arguments passed to the function. If so,
 	// generate an error message. The case of too few arguments
 	// will be handled below, when we run out of arguments.
-      if ((parms_.size()+1) > def->port_count()) {
+      if ((use_parms.size()+1) > def->port_count()) {
 	    cerr << get_fileline() << ": error: Parm count mismatch"
-		 << " passing " << parms_.size() << " arguments "
+		 << " passing " << use_parms.size() << " arguments "
 		 << " to constructor expecting " << (def->port_count()-1)
 		 << " arguments." << endl;
 	    des->errors += 1;
@@ -4745,9 +4761,10 @@ NetExpr* PENewClass::elaborate_expr_constructor_(Design*des, NetScope*scope,
       int parm_errors = 0;
       for (size_t idx = 1 ; idx < parms.size() ; idx += 1) {
 	      // While there are default arguments, check them.
-	    if (idx <= parms_.size() && parms_[idx-1]) {
-		  PExpr*tmp = parms_[idx-1];
-		  parms[idx] = elaborate_rval_expr(des, scope, def->port(idx)->net_type(),
+	    if (idx <= use_parms.size() && use_parms[idx-1]) {
+		  PExpr*tmp = use_parms[idx-1];
+		  parms[idx] = elaborate_rval_expr(des, scope,
+						   def->port(idx)->net_type(),
 						   def->port(idx)->data_type(),
 						   def->port(idx)->vector_width(),
 						   tmp, false);
@@ -4801,7 +4818,7 @@ NetExpr* PENewClass::elaborate_expr(Design*des, NetScope*scope,
 	// allocation alone.
       const netclass_t*ctype = dynamic_cast<const netclass_t*> (ntype);
 
-      obj = elaborate_expr_constructor_(des, scope, ctype, obj, flags);
+      obj = elaborate_expr_constructor_(des, scope, ctype, obj, flags, 0);
       return obj;
 }
 

elab_scope.cc

@@ -311,6 +311,12 @@ static void blend_class_constructors(PClass*pclass)
       if (iter_new == pclass->funcs.end())
 	    return;
 
+	// While we're here, look for a super.new() call. If we find
+	// it, strip it out of the constructor and set it aside for
+	// when we actually call the chained constructor.
+      pclass->chain = iter_new->second->extract_chain_constructor();
+
+
       map<perm_string,PFunction*>::iterator iter_new2 = pclass->funcs.find(new2);
       if (iter_new2 == pclass->funcs.end())
 	    return;
@@ -374,7 +380,10 @@ static void elaborate_scope_class(Design*des, NetScope*scope, PClass*pclass)
 	    }
       }
 
-      netclass_t*use_class = new netclass_t(use_type->name, use_base_class);
+      const static vector<PExpr*>no_args;
+      const vector<PExpr*>&use_chain_args = (pclass&&pclass->chain)? pclass->chain->chain_args() : no_args;
+
+      netclass_t*use_class = new netclass_t(use_type->name, use_base_class, use_chain_args);
 
 	// Class scopes have no parent scope, because references are
 	// not allowed to escape a class method.

netclass.cc

@@ -23,8 +23,8 @@
 
 using namespace std;
 
-netclass_t::netclass_t(perm_string name, netclass_t*sup)
-: name_(name), super_(sup), class_scope_(0)
+netclass_t::netclass_t(perm_string name, netclass_t*sup, const vector<PExpr*>&chain_args)
+: name_(name), super_(sup), chain_args_(chain_args), class_scope_(0)
 {
 }
 

netclass.h

@@ -30,10 +30,11 @@ class Design;
 class NetNet;
 class NetScope;
 class PClass;
+class PExpr;
 
 class netclass_t : public ivl_type_s {
     public:
-      netclass_t(perm_string class_name, netclass_t*par);
+      netclass_t(perm_string class_name, netclass_t*par, const vector<PExpr*>&pchain_args);
       ~netclass_t();
 
 	// Set the property of the class during elaboration. Set the
@@ -45,6 +46,9 @@ class netclass_t : public ivl_type_s {
 	// is used for the elaboration of methods (tasks/functions).
       void set_class_scope(NetScope*cscope);
 
+      inline const std::vector<PExpr*>& get_chain_args(void) const
+      { return chain_args_; }
+
 	// As an ivl_type_s object, the netclass is always an
 	// ivl_VT_CLASS object.
       ivl_variable_type_t base_type() const;
@@ -99,8 +103,10 @@ class netclass_t : public ivl_type_s {
     private:
       perm_string name_;
 	// If this is derived from another base class, point to it
-	// here.
+	// here. The super constructor may take arguments, and the
+	// chain_parms_ are those arguments.
       netclass_t*super_;
+      std::vector<PExpr*> chain_args_;
 	// Map properrty names to property table index.
       std::map<perm_string,size_t> properties_;
 	// Vector of properties.

parse.y

@@ -5853,9 +5853,9 @@ statement_item /* This is roughly statement_item in the LRM */
        out. */
 
   | implicit_class_handle '.' K_new '(' expression_list_with_nuls ')' ';'
-      { yyerror(@1, "sorry: Calls to superclass constructor not supported.");
-	yyerrok;
-        $$ = new PNoop;
+      { PChainConstructor*tmp = new PChainConstructor(*$5);
+	FILE_NAME(tmp, @3);
+	$$ = tmp;
       }
   | hierarchy_identifier '(' error ')' ';'
       { yyerror(@3, "error: Syntax error in task arguments.");

pform_dump.cc

@@ -821,6 +821,19 @@ void PCase::dump(ostream&out, unsigned ind) const
       out << setw(ind) << "" << "endcase" << endl;
 }
 
+void PChainConstructor::dump(ostream&out, unsigned ind) const
+{
+      out << setw(ind) << "" << "super.new(";
+      if (parms_.size() > 0) {
+	    if (parms_[0]) out << *parms_[0];
+      }
+      for (size_t idx = 1 ; idx < parms_.size() ; idx += 1) {
+	    out << ", ";
+	    if (parms_[idx]) out << *parms_[idx];
+      }
+      out << ");" << endl;
+}
+
 void PCondit::dump(ostream&out, unsigned ind) const
 {
       out << setw(ind) << "" << "if (" << *expr_ << ")" << endl;