Fix spacing
[yosys.git] / techlibs / xilinx / synth_xilinx.cc
index 7dbd980556e76f347aba547517dc9c1126cf1abf..abdf7f9cc478c1f73d44fb06a0a96b51082d917a 100644 (file)
@@ -62,9 +62,6 @@ struct SynthXilinxPass : public ScriptPass
                log("        generate an output netlist (and BLIF file) suitable for VPR\n");
                log("        (this feature is experimental and incomplete)\n");
                log("\n");
-               log("    -nocarry\n");
-               log("        disable inference of carry chains\n");
-               log("\n");
                log("    -nobram\n");
                log("        disable inference of block rams\n");
                log("\n");
@@ -80,6 +77,11 @@ struct SynthXilinxPass : public ScriptPass
                log("    -nowidelut\n");
                log("        do not use MUXF[78] resources to implement LUTs larger than LUT6s\n");
                log("\n");
+               log("    -widemux <int>\n");
+               log("        enable inference of hard multiplexer resources (MUXF[78]) for muxes at or\n");
+               log("        above this number of inputs (minimum value 2, recommended value >= 5).\n");
+               log("        default: 0 (no inference)\n");
+               log("\n");
                log("    -run <from_label>:<to_label>\n");
                log("        only run the commands between the labels (see below). an empty\n");
                log("        from label is synonymous to 'begin', and empty to label is\n");
@@ -102,6 +104,7 @@ struct SynthXilinxPass : public ScriptPass
 
        std::string top_opt, edif_file, blif_file, family;
        bool flatten, retime, vpr, nobram, nodram, nosrl, nocarry, nowidelut, abc9;
+       int widemux;
 
        void clear_flags() YS_OVERRIDE
        {
@@ -119,6 +122,7 @@ struct SynthXilinxPass : public ScriptPass
                nocarry = false;
                nowidelut = false;
                abc9 = false;
+               widemux = 0;
        }
 
        void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
@@ -189,6 +193,10 @@ struct SynthXilinxPass : public ScriptPass
                                nosrl = true;
                                continue;
                        }
+                       if (args[argidx] == "-widemux" && argidx+1 < args.size()) {
+                               widemux = std::stoi(args[++argidx]);
+                               continue;
+                       }
                        if (args[argidx] == "-abc9") {
                                abc9 = true;
                                continue;
@@ -200,6 +208,9 @@ struct SynthXilinxPass : public ScriptPass
                if (family != "xcup" && family != "xcu" && family != "xc7" && family != "xc6s")
                        log_cmd_error("Invalid Xilinx -family setting: %s\n", family.c_str());
 
+               if (widemux != 0 && widemux < 2)
+                       log_cmd_error("-widemux value must be 0 or >= 2.\n");
+
                if (!design->full_selection())
                        log_cmd_error("This command only operates on fully selected designs!\n");
 
@@ -215,9 +226,9 @@ struct SynthXilinxPass : public ScriptPass
        {
                if (check_label("begin")) {
                        if (vpr)
-                               run("read_verilog -lib -D _ABC -D_EXPLICIT_CARRY +/xilinx/cells_sim.v");
+                               run("read_verilog -lib -icells -D _ABC -D_EXPLICIT_CARRY +/xilinx/cells_sim.v");
                        else
-                               run("read_verilog -lib -D _ABC +/xilinx/cells_sim.v");
+                               run("read_verilog -lib -icells -D _ABC +/xilinx/cells_sim.v");
 
                        run("read_verilog -lib +/xilinx/cells_xtra.v");
 
@@ -227,26 +238,21 @@ struct SynthXilinxPass : public ScriptPass
                        run(stringf("hierarchy -check %s", top_opt.c_str()));
                }
 
-               if (check_label("flatten", "(with '-flatten' only)")) {
-                       if (flatten || help_mode) {
-                               run("proc");
-                               run("flatten");
-                       }
-               }
-
                if (check_label("coarse")) {
-                       run("synth -run coarse");
+                       if (help_mode)
+                               run("synth -keepdc -run coarse [-flatten]", "(with '-flatten')");
+                       else
+                               run("synth -keepdc -run coarse" + std::string(flatten ? "" : " -flatten"), "(with '-flatten')");
+
+                       if (widemux > 0 || help_mode)
+                               run("muxpack", "    ('-widemux' only)");
 
                        // shregmap -tech xilinx can cope with $shiftx and $mux
                        //   cells for identifying variable-length shift registers,
                        //   so attempt to convert $pmux-es to the former
-                       if (!nosrl || help_mode)
-                               run("pmux2shiftx", "(skip if '-nosrl')");
-
-                       // Run a number of peephole optimisations, including one
-                       //   that optimises $mul cells driving $shiftx's B input
-                       //   and that aids wide mux analysis
-                       run("peepopt");
+                       // Also: wide multiplexer inference benefits from this too
+                       if (!(nosrl && widemux == 0) || help_mode)
+                               run("pmux2shiftx", "(skip if '-nosrl' and '-widemux=0')");
                }
 
                if (check_label("bram", "(skip if '-nobram')")) {
@@ -264,36 +270,74 @@ struct SynthXilinxPass : public ScriptPass
                }
 
                if (check_label("fine")) {
-                       run("opt -fast -full");
+                       if (widemux > 0)
+                               run("opt -fast -mux_bool -undriven -fine"); // Necessary to omit -mux_undef otherwise muxcover
+                                                                           // performs less efficiently
+                       else
+                               run("opt -fast -full");
                        run("memory_map");
                        run("dffsr2dff");
                        run("dff2dffe");
+                       if (help_mode) {
+                               run("simplemap t:$mux", "         ('-widemux' only)");
+                               run("muxcover <internal options>, ('-widemux' only)");
+                       }
+                       else if (widemux > 0) {
+                               run("simplemap t:$mux");
+                               constexpr int cost_mux2 = 100;
+                               std::string muxcover_args = stringf(" -nodecode -mux2=%d", cost_mux2);
+                               switch (widemux) {
+                                       case  2: muxcover_args += stringf(" -mux4=%d -mux8=%d -mux16=%d", cost_mux2+1, cost_mux2+2, cost_mux2+3); break;
+                                       case  3:
+                                       case  4: muxcover_args += stringf(" -mux4=%d -mux8=%d -mux16=%d", cost_mux2*(widemux-1)-2, cost_mux2*(widemux-1)-1, cost_mux2*(widemux-1)); break;
+                                       case  5:
+                                       case  6:
+                                       case  7:
+                                       case  8: muxcover_args += stringf(" -mux8=%d -mux16=%d", cost_mux2*(widemux-1)-1, cost_mux2*(widemux-1)); break;
+                                       case  9:
+                                       case 10:
+                                       case 11:
+                                       case 12:
+                                       case 13:
+                                       case 14:
+                                       case 15:
+                                       default: muxcover_args += stringf(" -mux16=%d", cost_mux2*(widemux-1)-1); break;
+                               }
+                               run("muxcover " + muxcover_args);
+                       }
                        run("opt -full");
 
                        if (!nosrl || help_mode) {
                                // shregmap operates on bit-level flops, not word-level,
                                //   so break those down here
-                               run("simplemap t:$dff t:$dffe", "(skip if '-nosrl')");
+                               run("simplemap t:$dff t:$dffe", "       (skip if '-nosrl')");
                                // shregmap with '-tech xilinx' infers variable length shift regs
                                run("shregmap -tech xilinx -minlen 3", "(skip if '-nosrl')");
                        }
 
-                       std::string techmap_files = " -map +/techmap.v";
+                       std::string techmap_args = " -map +/techmap.v";
+                       if (help_mode)
+                               techmap_args += " [-map +/xilinx/mux_map.v]";
+                       else if (widemux > 0)
+                               techmap_args += stringf(" -D MIN_MUX_INPUTS=%d -map +/xilinx/mux_map.v", widemux);
                        if (help_mode)
-                               techmap_files += " [-map +/xilinx/arith_map.v]";
+                               techmap_args += " [-map +/xilinx/arith_map.v]";
                        else if (!nocarry) {
-                               techmap_files += " -map +/xilinx/arith_map.v";
+                               techmap_args += " -map +/xilinx/arith_map.v";
                                if (vpr)
-                                       techmap_files += " -D _EXPLICIT_CARRY";
+                                       techmap_args += " -D _EXPLICIT_CARRY";
                                else if (abc9)
-                                       techmap_files += " -D _CLB_CARRY";
+                                       techmap_args += " -D _CLB_CARRY";
                        }
-                       run("techmap " + techmap_files);
+                       run("techmap " + techmap_args);
                        run("opt -fast");
                }
 
                if (check_label("map_cells")) {
-                       run("techmap -map +/techmap.v -map +/xilinx/cells_map.v");
+                       std::string techmap_args = "-map +/techmap.v -D _ABC -map +/xilinx/cells_map.v";
+                       if (widemux > 0)
+                               techmap_args += stringf(" -D MIN_MUX_INPUTS=%d", widemux);
+                       run("techmap " + techmap_args);
                        run("clean");
                }