Allow muxcover costs to be changed

diff --git a/passes/techmap/muxcover.cc b/passes/techmap/muxcover.cc
index 12da9ed0c0160b2793cbaa229687f1f6dd455210..32102436ddc6e010b8d192f2b38378a8280806a1 100644 (file)
--- a/passes/techmap/muxcover.cc
+++ b/passes/techmap/muxcover.cc
@@ -58,12 +58,21 @@ struct MuxcoverWorker
        bool use_mux16;
        bool nodecode;
 
+       int cost_mux2;
+       int cost_mux4;
+       int cost_mux8;
+       int cost_mux16;
+
        MuxcoverWorker(Module *module) : module(module), sigmap(module)
        {
                use_mux4 = false;
                use_mux8 = false;
                use_mux16 = false;
                nodecode = false;
+               cost_mux2 = COST_MUX2;
+               cost_mux4 = COST_MUX4;
+               cost_mux8 = COST_MUX8;
+               cost_mux16 = COST_MUX16;
                decode_mux_counter = 0;
        }
 
@@ -157,7 +166,7 @@ struct MuxcoverWorker
                if (std::get<2>(entry))
                        return 0;
 
-               return COST_MUX2 / GetSize(std::get<1>(entry));
+               return cost_mux2 / GetSize(std::get<1>(entry));
        }
 
        void implement_decode_mux(SigBit ctrl_bit)
@@ -209,7 +218,7 @@ struct MuxcoverWorker
                        mux.inputs.push_back(B);
                        mux.selects.push_back(S1);
 
-                       mux.cost += COST_MUX2;
+                       mux.cost += cost_mux2;
                        mux.cost += find_best_cover(tree, A);
                        mux.cost += find_best_cover(tree, B);
 
@@ -247,7 +256,7 @@ struct MuxcoverWorker
                                mux.selects.push_back(S1);
                                mux.selects.push_back(T1);
 
-                               mux.cost += COST_MUX4;
+                               mux.cost += cost_mux4;
                                mux.cost += find_best_cover(tree, A);
                                mux.cost += find_best_cover(tree, B);
                                mux.cost += find_best_cover(tree, C);
@@ -310,7 +319,7 @@ struct MuxcoverWorker
                                mux.selects.push_back(T1);
                                mux.selects.push_back(U1);
 
-                               mux.cost += COST_MUX8;
+                               mux.cost += cost_mux8;
                                mux.cost += find_best_cover(tree, A);
                                mux.cost += find_best_cover(tree, B);
                                mux.cost += find_best_cover(tree, C);
@@ -414,7 +423,7 @@ struct MuxcoverWorker
                                mux.selects.push_back(U1);
                                mux.selects.push_back(V1);
 
-                               mux.cost += COST_MUX16;
+                               mux.cost += cost_mux16;
                                mux.cost += find_best_cover(tree, A);
                                mux.cost += find_best_cover(tree, B);
                                mux.cost += find_best_cover(tree, C);
@@ -569,9 +578,11 @@ struct MuxcoverPass : public Pass {
                log("\n");
                log("Cover trees of $_MUX_ cells with $_MUX{4,8,16}_ cells\n");
                log("\n");
-               log("    -mux4, -mux8, -mux16\n");
-               log("        Use the specified types of MUXes. If none of those options are used,\n");
-               log("        the effect is the same as if all of them where used.\n");
+               log("    -mux4[=cost], -mux8[=cost], -mux16[=cost]\n");
+               log("        Use the specified types of MUXes (with optional integer costs). If none\n");
+               log("        of these options are given, the effect is the same as if all of them are.\n");
+               log("        Default costs: $_MUX_ = %d, $_MUX4_ = %d,\n", COST_MUX2, COST_MUX4);
+               log("                       $_MUX8_ = %d, $_MUX16_ = %d\n", COST_MUX8, COST_MUX16);
                log("\n");
                log("    -nodecode\n");
                log("        Do not insert decoder logic. This reduces the number of possible\n");
@@ -587,23 +598,39 @@ struct MuxcoverPass : public Pass {
                bool use_mux8 = false;
                bool use_mux16 = false;
                bool nodecode = false;
+               int cost_mux4 = COST_MUX4;
+               int cost_mux8 = COST_MUX8;
+               int cost_mux16 = COST_MUX16;
 
                size_t argidx;
                for (argidx = 1; argidx < args.size(); argidx++)
                {
-                       if (args[argidx] == "-mux4") {
+                       const auto &arg = args[argidx];
+                       if (arg.size() >= 5 && arg.substr(0,5) == "-mux4") {
                                use_mux4 = true;
+                               if (arg.size() > 5) {
+                                       if (arg[5] != '=') break;
+                                       cost_mux4 = atoi(arg.substr(5).c_str());
+                               }
                                continue;
                        }
-                       if (args[argidx] == "-mux8") {
+                       if (arg.size() >= 5 && arg.substr(0,5) == "-mux8") {
                                use_mux8 = true;
+                               if (arg.size() > 5) {
+                                       if (arg[5] != '=') break;
+                                       cost_mux8 = atoi(arg.substr(5).c_str());
+                               }
                                continue;
                        }
-                       if (args[argidx] == "-mux16") {
+                       if (arg.size() >= 6 && arg.substr(0,6) == "-mux16") {
                                use_mux16 = true;
+                               if (arg.size() > 6) {
+                                       if (arg[6] != '=') break;
+                                       cost_mux16 = atoi(arg.substr(6).c_str());
+                               }
                                continue;
                        }
-                       if (args[argidx] == "-nodecode") {
+                       if (arg == "-nodecode") {
                                nodecode = true;
                                continue;
                        }
@@ -623,6 +650,9 @@ struct MuxcoverPass : public Pass {
                        worker.use_mux4 = use_mux4;
                        worker.use_mux8 = use_mux8;
                        worker.use_mux16 = use_mux16;
+                       worker.cost_mux4 = cost_mux4;
+                       worker.cost_mux8 = cost_mux8;
+                       worker.cost_mux16 = cost_mux16;
                        worker.nodecode = nodecode;
                        worker.run();
                }