From 0804eccfecfbc004239524195cf17b3c761a7d62 Mon Sep 17 00:00:00 2001
From: Cary R <cygcary@yahoo.com>
Date: Fri, 29 Aug 2008 10:52:09 -0700
Subject: [PATCH] Evaluate constant real EQ and NE constructs.

This patch adds code to evaluate constant == and != with real values.
---
 eval_tree.cc | 79 ++++++++++++++++++++++++++++++++++++++++++----------
 netlist.h    |  1 +
 2 files changed, 65 insertions(+), 15 deletions(-)

diff --git a/eval_tree.cc b/eval_tree.cc
index 99e408a60..057ed003c 100644
--- a/eval_tree.cc
+++ b/eval_tree.cc
@@ -340,19 +340,15 @@ NetEConst* NetEBComp::eval_leeq_real_(NetExpr*le, NetExpr*ri, bool eq_flag)
       switch (le->expr_type()) {
 	  case IVL_VT_REAL:
 	    rtmp = dynamic_cast<NetECReal*> (le);
-	    if (rtmp == 0)
-		  return 0;
-
+	    if (rtmp == 0) return 0;
 	    lv = rtmp->value().as_double();
 	    break;
 
 	  case IVL_VT_LOGIC:
 	  case IVL_VT_BOOL:
 	    vtmp = dynamic_cast<NetEConst*> (le);
-	    if (vtmp == 0)
-		  return 0;
-
-	    lv = vtmp->value().as_long();
+	    if (vtmp == 0) return 0;
+	    lv = vtmp->value().as_double();
 	    break;
 
 	  default:
@@ -361,23 +357,18 @@ NetEConst* NetEBComp::eval_leeq_real_(NetExpr*le, NetExpr*ri, bool eq_flag)
 	    assert(0);
       }
 
-
       switch (ri->expr_type()) {
 	  case IVL_VT_REAL:
 	    rtmp = dynamic_cast<NetECReal*> (ri);
-	    if (rtmp == 0)
-		  return 0;
-
+	    if (rtmp == 0) return 0;
 	    rv = rtmp->value().as_double();
 	    break;
 
 	  case IVL_VT_LOGIC:
 	  case IVL_VT_BOOL:
 	    vtmp = dynamic_cast<NetEConst*> (ri);
-	    if (vtmp == 0)
-		  return 0;
-
-	    rv = vtmp->value().as_long();
+	    if (vtmp == 0) return 0;
+	    rv = vtmp->value().as_double();
 	    break;
 
 	  default:
@@ -563,8 +554,66 @@ NetEConst* NetEBComp::eval_gteq_()
       }
 }
 
+NetEConst* NetEBComp::eval_eqeq_real_(NetExpr*le, NetExpr*ri, bool ne_flag)
+{
+      NetEConst*vtmp;
+      NetECReal*rtmp;
+      double lv, rv;
+
+      switch (le->expr_type()) {
+	  case IVL_VT_REAL:
+	    rtmp = dynamic_cast<NetECReal*> (le);
+	    if (rtmp == 0) return 0;
+	    lv = rtmp->value().as_double();
+	    break;
+
+	  case IVL_VT_LOGIC:
+	  case IVL_VT_BOOL:
+	    vtmp = dynamic_cast<NetEConst*> (le);
+	    if (vtmp == 0) return 0;
+	    lv = vtmp->value().as_double();
+	    break;
+
+	  default:
+	    cerr << get_fileline() << ": internal error: "
+		 << "Unexpected expression type? " << le->expr_type() << endl;
+	    assert(0);
+      }
+
+      switch (ri->expr_type()) {
+	  case IVL_VT_REAL:
+	    rtmp = dynamic_cast<NetECReal*> (ri);
+	    if (rtmp == 0) return 0;
+	    rv = rtmp->value().as_double();
+	    break;
+
+	  case IVL_VT_LOGIC:
+	  case IVL_VT_BOOL:
+	    vtmp = dynamic_cast<NetEConst*> (ri);
+	    if (vtmp == 0) return 0;
+	    rv = vtmp->value().as_double();
+	    break;
+
+	  default:
+	    cerr << get_fileline() << ": internal error: "
+		 << "Unexpected expression type? " << ri->expr_type() << endl;
+	    assert(0);
+      }
+
+      verinum result((lv == rv ^ ne_flag) ? verinum::V1 : verinum::V0, 1);
+      vtmp = new NetEConst(result);
+      vtmp->set_line(*this);
+
+      return vtmp;
+}
+
 NetEConst* NetEBComp::eval_eqeq_(bool ne_flag)
 {
+      if (right_->expr_type() == IVL_VT_REAL)
+	    return eval_eqeq_real_(right_, left_, ne_flag);
+      if (left_->expr_type() == IVL_VT_REAL)
+	    return eval_eqeq_real_(right_, left_, ne_flag);
+
       NetEConst*l = dynamic_cast<NetEConst*>(left_);
       if (l == 0) return 0;
       NetEConst*r = dynamic_cast<NetEConst*>(right_);
diff --git a/netlist.h b/netlist.h
index e86b3936c..ebeb07683 100644
--- a/netlist.h
+++ b/netlist.h
@@ -3206,6 +3206,7 @@ class NetEBComp : public NetEBinary {
       NetEConst* must_be_leeq_(NetExpr*le, const verinum&rv, bool eq_flag);
 
       NetEConst*eval_eqeq_(bool ne_flag);
+      NetEConst*eval_eqeq_real_(NetExpr*le, NetExpr*ri, bool ne_flag);
       NetEConst*eval_less_();
       NetEConst*eval_leeq_();
       NetEConst*eval_leeq_real_(NetExpr*le, NetExpr*ri, bool eq_flag);