From e485ac99810d3a06fc2cc1e4a4828affc5f98d70 Mon Sep 17 00:00:00 2001
From: Martin Whitaker <mailing-list@martin-whitaker.me.uk>
Date: Sat, 7 Jan 2012 12:36:28 +0000
Subject: [PATCH] Fix for pr3465541.

vvp_net_t::send_vec8_pv() needs to call the output filter if one is
present, and vvp_wire_vec4::filter_vec8() needs to support part selects.
---
 vvp/vvp_net.h      | 27 ++++++++++++++++++++++++---
 vvp/vvp_net_sig.cc | 18 +++++++++++++-----
 2 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/vvp/vvp_net.h b/vvp/vvp_net.h
index 5fd8525cc..e9c55c78a 100644
--- a/vvp/vvp_net.h
+++ b/vvp/vvp_net.h
@@ -1546,10 +1546,9 @@ inline void vvp_send_vec4_pv(vvp_net_ptr_t ptr, const vvp_vector4_t&val,
       }
 }
 
-inline void vvp_net_t::send_vec8_pv(const vvp_vector8_t&val,
-				    unsigned base, unsigned wid, unsigned vwid)
+inline void vvp_send_vec8_pv(vvp_net_ptr_t ptr, const vvp_vector8_t&val,
+			     unsigned base, unsigned wid, unsigned vwid)
 {
-      vvp_net_ptr_t ptr = out_;
       while (class vvp_net_t*cur = ptr.ptr()) {
 	    vvp_net_ptr_t next = cur->port[ptr.port()];
 
@@ -1623,6 +1622,28 @@ inline void vvp_net_t::send_vec8(const vvp_vector8_t&val)
       }
 }
 
+inline void vvp_net_t::send_vec8_pv(const vvp_vector8_t&val,
+				    unsigned base, unsigned wid, unsigned vwid)
+{
+      if (fil == 0) {
+	    vvp_send_vec8_pv(out_, val, base, wid, vwid);
+	    return;
+      }
+
+      assert(val.size() == wid);
+      vvp_vector8_t rep;
+      switch (fil->filter_vec8(val, rep, base, vwid)) {
+	  case vvp_net_fil_t::STOP:
+	    break;
+	  case vvp_net_fil_t::PROP:
+	    vvp_send_vec8_pv(out_, val, base, wid, vwid);
+	    break;
+	  case vvp_net_fil_t::REPL:
+	    vvp_send_vec8_pv(out_, rep, base, wid, vwid);
+	    break;
+      }
+}
+
 inline void vvp_net_t::send_real(double val, vvp_context_t context)
 {
       if (fil && ! fil->filter_real(val))
diff --git a/vvp/vvp_net_sig.cc b/vvp/vvp_net_sig.cc
index 1da9edb85..183c81b8e 100644
--- a/vvp/vvp_net_sig.cc
+++ b/vvp/vvp_net_sig.cc
@@ -651,12 +651,20 @@ vvp_net_fil_t::prop_t vvp_wire_vec4::filter_vec8(const vvp_vector8_t&bit,
                                                  unsigned base,
                                                  unsigned vwid)
 {
-	// For now there is no support for a non-zero base.
-      assert(0 == base);
       assert(bits4_.size() == vwid);
-      assert(bits4_.size() == bit.size());
-      bits4_ = reduce4(bit);
-      return filter_mask_(bit, vvp_vector8_t(force4_,6,6), rep, 0);
+
+	// Keep track of the value being driven from this net, even if
+	// it is not ultimately what survives the force filter.
+      vvp_vector4_t bit4 (reduce4(bit));
+      if (base==0 && bit4.size()==vwid) {
+	    if (bits4_ .eeq( bit4 ) && !needs_init_) return STOP;
+	    bits4_ = bit4;
+      } else {
+	    bits4_.set_vec(base, bit4);
+      }
+
+      needs_init_ = false;
+      return filter_mask_(bit, vvp_vector8_t(force4_,6,6), rep, base);
 }
 
 unsigned vvp_wire_vec4::filter_size() const