Add part select support to vvp_vector8_t

Need a convenient way to handle part selects of vvp_vector8_t objects.

vvp/vvp_net.cc

@@ -1840,6 +1840,34 @@ bool vvp_vector8_t::eeq(const vvp_vector8_t&that) const
       return true;
 }
 
+vvp_vector8_t vvp_vector8_t::subvalue(unsigned base, unsigned wid) const
+{
+      vvp_vector8_t tmp (wid);
+
+      unsigned idx = 0;
+      while (base+idx < size_) {
+	    tmp.bits_[idx] = bits_[base+idx];
+	    idx += 1;
+      }
+
+      return tmp;
+}
+
+vvp_vector8_t part_expand(const vvp_vector8_t&that, unsigned wid, unsigned off)
+{
+      assert(off < wid);
+      vvp_vector8_t tmp (wid);
+
+      unsigned idx = off;
+
+      while (idx < wid && that.size_ > (idx-off)) {
+	    tmp.bits_[idx] = that.bits_[idx-off];
+	    idx += 1;
+      }
+
+      return tmp;
+}
+
 ostream& operator<<(ostream&out, const vvp_vector8_t&that)
 {
       out << "C8<";

vvp/vvp_net.h

@@ -542,6 +542,8 @@ extern ostream& operator<< (ostream&, vvp_scalar_t);
  */
 class vvp_vector8_t {
 
+      friend vvp_vector8_t part_expand(const vvp_vector8_t&, unsigned, unsigned);
+
     public:
       explicit vvp_vector8_t(unsigned size =0);
 	// Make a vvp_vector8_t from a vector4 and a specified strength.
@@ -554,6 +556,7 @@ class vvp_vector8_t {
 
       unsigned size() const { return size_; }
       vvp_scalar_t value(unsigned idx) const;
+      vvp_vector8_t subvalue(unsigned idx, unsigned size) const;
       void set_bit(unsigned idx, vvp_scalar_t val);
 
 	// Test that the vectors are exactly equal
@@ -576,6 +579,7 @@ extern vvp_vector8_t resistive_reduction(const vvp_vector8_t&a);
   /* The reduce4 function converts a vector8 to a vector4, losing
      strength information in the process. */
 extern vvp_vector4_t reduce4(const vvp_vector8_t&that);
+extern vvp_vector8_t part_expand(const vvp_vector8_t&a, unsigned wid, unsigned off);
   /* Print a vector8 value to a stream. */
 extern ostream& operator<< (ostream&, const vvp_vector8_t&);
 
@@ -643,6 +647,8 @@ template <class T> class vvp_sub_pointer_t {
 };
 
 typedef vvp_sub_pointer_t<vvp_net_t> vvp_net_ptr_t;
+template <class T> ostream& operator << (ostream&out, vvp_sub_pointer_t<T> val)
+{ out << val.ptr() << "[" << val.port() << "]"; return out; }
 
 /*
  * This is the basic unit of netlist connectivity. It is a fan-in of