From d2ff77d56c0972b87eeb726c3d8108b4ffd3de5f Mon Sep 17 00:00:00 2001
From: Stephen Williams <steve@icarus.com>
Date: Sat, 1 Mar 2014 08:38:23 -0800
Subject: [PATCH] More standard handling of unsized numbers as system task
 arguments.

---
 elab_expr.cc | 30 +++++++++++++++++++++++++-----
 netlist.h    |  2 +-
 netmisc.cc   |  2 +-
 3 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/elab_expr.cc b/elab_expr.cc
index 6d37cc515..57ef9ecc0 100644
--- a/elab_expr.cc
+++ b/elab_expr.cc
@@ -1326,6 +1326,13 @@ unsigned PECallFunction::test_width_method_(Design*des, NetScope*scope,
 
 NetExpr*PECallFunction::cast_to_width_(NetExpr*expr, unsigned wid) const
 {
+      if (debug_elaborate) {
+            cerr << get_fileline() << ": PECallFunction::cast_to_width_: "
+		 << "cast to " << wid
+                 << " bits " << (signed_flag_?"signed":"unsigned")
+		 << " from expr_width()=" << expr->expr_width() << endl;
+      }
+
         /* If the expression is a const, then replace it with a new
            const. This is a more efficient result. */
       if (NetEConst*tmp = dynamic_cast<NetEConst*>(expr)) {
@@ -1338,10 +1345,6 @@ NetExpr*PECallFunction::cast_to_width_(NetExpr*expr, unsigned wid) const
             return tmp;
       }
 
-      if (debug_elaborate)
-            cerr << get_fileline() << ": debug: cast to " << wid
-                 << " bits " << (signed_flag_?"signed":"unsigned") << endl;
-
       NetESelect*tmp = new NetESelect(expr, 0, wid);
       tmp->cast_signed(signed_flag_);
       tmp->set_line(*this);
@@ -1385,6 +1388,10 @@ NetExpr* PECallFunction::elaborate_sfunc_(Design*des, NetScope*scope,
 		  return 0;
 	    }
 
+	    if (debug_elaborate) {
+		  cerr << get_fileline() << ": PECallFunction::elaborate_sfunc_: "
+		       << name << " expression is the argument cast to expr_wid=" << expr_wid << endl;
+	    }
 	    PExpr*expr = parms_[0];
 	    NetExpr*sub = expr->elaborate_expr(des, scope, expr_width_, flags);
 
@@ -4916,10 +4923,23 @@ unsigned PENumber::test_width(Design*, NetScope*, width_mode_t&mode)
                   expr_width_ = integer_width;
                   mode = UNSIZED;
             } else if (mode < LOSSLESS) {
-                  mode = LOSSLESS;
+		  if (expr_width_ < integer_width) {
+			expr_width_ = integer_width;
+			if (mode < UNSIZED)
+			      mode = UNSIZED;
+		  } else {
+			mode = LOSSLESS;
+		  }
             }
       }
 
+      if (debug_elaborate) {
+	    cerr << get_fileline() << ": PENumber::test_width: "
+		 << "Value=" << *value_
+		 << ", width=" << expr_width_
+		 << ", output mode=" << width_mode_name(mode) << endl;
+      }
+
       return expr_width_;
 }
 
diff --git a/netlist.h b/netlist.h
index 6cefc4c15..81b62b5d4 100644
--- a/netlist.h
+++ b/netlist.h
@@ -1998,7 +1998,7 @@ class NetEConst  : public NetExpr {
         /* This method allows the constant value to be converted
            to an unsized value. This is used after evaluating a
            unsized constant expression. */
-      virtual void trim();
+      void trim();
 
       virtual void expr_scan(struct expr_scan_t*) const;
       virtual void dump(ostream&) const;
diff --git a/netmisc.cc b/netmisc.cc
index 6bb07a8f0..a7184696e 100644
--- a/netmisc.cc
+++ b/netmisc.cc
@@ -910,7 +910,7 @@ NetExpr* elab_sys_task_arg(Design*des, NetScope*scope, perm_string name,
               // determine the exact width required to hold the result.
               // But leave literal numbers exactly as the user supplied
               // them.
-            if ((mode >= PExpr::LOSSLESS) && !dynamic_cast<PENumber*>(pe))
+            if ((mode >= PExpr::LOSSLESS) && !dynamic_cast<PENumber*>(pe) && tmp->expr_width()>32)
                   ce->trim();
       }