Basic elaboration of analog contribution statements.

Get at least basic elaboration of analog processes and contribution
statements. Bring the statements and analog statements together and
net future elaboration work sort out which statements are valid in
a given context. This makes sense because there really is a lot of
syntactic overlap, and analog behavioral code is processed somewhat
sequentially.

AStatement.h

@@ -23,6 +23,7 @@
 # include  "ivl_target.h"
 # include  "StringHeap.h"
 # include  "LineInfo.h"
+# include  "Statement.h"
 # include  "PExpr.h"
 
 class PExpr;
@@ -30,36 +31,19 @@ class NetAnalog;
 class NetScope;
 class Design;
 
-class AStatement  : public LineInfo {
-
-    public:
-      AStatement() { }
-      virtual ~AStatement() =0;
-
-      virtual void dump(ostream&out, unsigned ind) const;
-      virtual NetAnalog* elaborate(Design*des, NetScope*scope) const;
-      virtual void elaborate_scope(Design*des, NetScope*scope) const;
-      virtual void elaborate_sig(Design*des, NetScope*scope) const;
-
-      map<perm_string,PExpr*> attributes;
-
-    private: // not implemented
-      AStatement(const AStatement&);
-      AStatement& operator= (const AStatement&);
-};
-
 /*
  * A contribution statement is like an assignment: there is an l-value
  * expression and an r-value expression. The l-value is a branch probe
  * expression.
  */
-class AContrib : public AStatement {
+class AContrib : public Statement {
 
     public:
       AContrib(PExpr*lval, PExpr*rval);
       ~AContrib();
 
       virtual void dump(ostream&out, unsigned ind) const;
+      virtual NetProc* elaborate(Design*des, NetScope*scope) const;
 
     private:
       PExpr*lval_;
@@ -74,7 +58,7 @@ class AContrib : public AStatement {
 class AProcess : public LineInfo {
 
     public:
-      AProcess(ivl_process_type_t t, AStatement*st)
+      AProcess(ivl_process_type_t t, Statement*st)
       : type_(t), statement_(st) { }
 
       ~AProcess();
@@ -82,7 +66,7 @@ class AProcess : public LineInfo {
       bool elaborate(Design*des, NetScope*scope) const;
 
       ivl_process_type_t type() const { return type_; }
-      AStatement*statement() { return statement_; }
+      Statement*statement() { return statement_; }
 
       map<perm_string,PExpr*> attributes;
 
@@ -91,7 +75,7 @@ class AProcess : public LineInfo {
 
     private:
       ivl_process_type_t type_;
-      AStatement*statement_;
+      Statement*statement_;
 
     private: // not implemented
       AProcess(const AProcess&);