Call opt_expr -mux_undef to get rid of 1'bx in muxes prior to abc

diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc
index 7b20a7132c3ba02cd107c5f1cc1b395051c82c55..f1e887df8d20df30cc0a659f8cdf289cc851fac9 100644 (file)
--- a/techlibs/xilinx/synth_xilinx.cc
+++ b/techlibs/xilinx/synth_xilinx.cc
@@ -299,6 +299,7 @@ struct SynthXilinxPass : public ScriptPass
                }
 
                if (check_label("map_luts")) {
+                       run("opt_expr -mux_undef");
                        if (abc == "abc9")
                                run(abc + " -lut +/xilinx/abc_xc7.lut -box +/xilinx/abc_xc7.box -W " + XC7_WIRE_DELAY + string(retime ? " -dff" : ""));
                        else if (help_mode)