synth_ice40: add -relut option, to run ice40_unlut and opt_lut.

diff --git a/techlibs/ice40/synth_ice40.cc b/techlibs/ice40/synth_ice40.cc
index 93965a55dbfb16c098220fdce341ac33d9f48735..7094db50d393c3bfd9b8dc3c2e0a311485a9b6ab 100644 (file)
--- a/techlibs/ice40/synth_ice40.cc
+++ b/techlibs/ice40/synth_ice40.cc
@@ -63,6 +63,9 @@ struct SynthIce40Pass : public ScriptPass
                log("    -retime\n");
                log("        run 'abc' with -dff option\n");
                log("\n");
+               log("    -relut\n");
+               log("        combine LUTs after synthesis\n");
+               log("\n");
                log("    -nocarry\n");
                log("        do not use SB_CARRY cells in output netlist\n");
                log("\n");
@@ -90,7 +93,7 @@ struct SynthIce40Pass : public ScriptPass
        }
 
        string top_opt, blif_file, edif_file, json_file;
-       bool nocarry, nodffe, nobram, flatten, retime, abc2, vpr;
+       bool nocarry, nodffe, nobram, flatten, retime, relut, abc2, vpr;
        int min_ce_use;
 
        void clear_flags() YS_OVERRIDE
@@ -105,6 +108,7 @@ struct SynthIce40Pass : public ScriptPass
                nobram = false;
                flatten = true;
                retime = false;
+               relut = false;
                abc2 = false;
                vpr = false;
        }
@@ -153,6 +157,10 @@ struct SynthIce40Pass : public ScriptPass
                                retime = true;
                                continue;
                        }
+                       if (args[argidx] == "-relut") {
+                               relut = true;
+                               continue;
+                       }
                        if (args[argidx] == "-nocarry") {
                                nocarry = true;
                                continue;
@@ -259,6 +267,10 @@ struct SynthIce40Pass : public ScriptPass
                        run("techmap -map +/ice40/latches_map.v");
                        run("abc -lut 4");
                        run("clean");
+                       if (relut || help_mode) {
+                               run("ice40_unlut", "(only if -relut)");
+                               run("opt_lut", "    (only if -relut)");
+                       }
                }
 
                if (check_label("map_cells"))