Rework help_mode for synth_xilinx -widemux

diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc
index c139fb3c4e9f783d70de947b6d8c69e8b940eed0..199d0737dd3a456a316dc6432a9813d920d419d9 100644 (file)
--- a/techlibs/xilinx/synth_xilinx.cc
+++ b/techlibs/xilinx/synth_xilinx.cc
@@ -276,29 +276,30 @@ struct SynthXilinxPass : public ScriptPass
                        run("memory_map");
                        run("dffsr2dff");
                        run("dff2dffe");
-                       if (widemux > 0 || help_mode) {
-                               run("simplemap t:$mux", "                        ('-widemux' only)");
-                               if (widemux > 0 || help_mode) {
-                                       std::string muxcover_args = " -dmux=0";
-                                       switch (widemux) {
-                                               // NB: Cost of mux2 is 100; mux8 should cost between 3 and 4
-                                               //     of those so that 4:1 muxes and below are implemented
-                                               //     out of mux2s
-                                               case  5: muxcover_args += " -mux8=350 -mux16=400"; break;
-                                               case  6: muxcover_args += " -mux8=450 -mux16=500"; break;
-                                               case  7: muxcover_args += " -mux8=550 -mux16=600"; break;
-                                               case  8: muxcover_args += " -mux8=650 -mux16=700"; break;
-                                               case  9: muxcover_args += " -mux16=750"; break;
-                                               case 10: muxcover_args += " -mux16=850"; break;
-                                               case 11: muxcover_args += " -mux16=950"; break;
-                                               case 12: muxcover_args += " -mux16=1050"; break;
-                                               case 13: muxcover_args += " -mux16=1150"; break;
-                                               case 14: muxcover_args += " -mux16=1250"; break;
-                                               case 15: muxcover_args += " -mux16=1350"; break;
-                                               default: muxcover_args += " -mux16=1450"; break;
-                                       }
-                                       run("muxcover " + muxcover_args, "('-widemux' only)");
+                       if (help_mode) {
+                               run("simplemap t:$mux", "                 ('-widemux' only)");
+                               run("muxcover -dmux=0 -mux8=<cost> -mux16=<cost>, ('-widemux' only)");
+                       }
+                       else if (widemux > 0) {
+                               std::string muxcover_args = " -dmux=0";
+                               switch (widemux) {
+                                       // NB: Cost of mux2 is 100; mux8 should cost between 3 and 4
+                                       //     of those so that 4:1 muxes and below are implemented
+                                       //     out of mux2s
+                                       case  5: muxcover_args += " -mux8=350 -mux16=400"; break;
+                                       case  6: muxcover_args += " -mux8=450 -mux16=500"; break;
+                                       case  7: muxcover_args += " -mux8=550 -mux16=600"; break;
+                                       case  8: muxcover_args += " -mux8=650 -mux16=700"; break;
+                                       case  9: muxcover_args += " -mux16=750"; break;
+                                       case 10: muxcover_args += " -mux16=850"; break;
+                                       case 11: muxcover_args += " -mux16=950"; break;
+                                       case 12: muxcover_args += " -mux16=1050"; break;
+                                       case 13: muxcover_args += " -mux16=1150"; break;
+                                       case 14: muxcover_args += " -mux16=1250"; break;
+                                       case 15: muxcover_args += " -mux16=1350"; break;
+                                       default: muxcover_args += " -mux16=1450"; break;
                                }
+                               run("muxcover " + muxcover_args);
                        }
                        run("opt -full");