From ba07cba6ce73a979e4ce25a027fbf9cb8723a8c8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Povi=C5=A1er?= <povik@cutebit.org>
Date: Thu, 22 Feb 2024 17:23:28 +0100
Subject: [PATCH] synth: Introduce `-inject` for amending techmap

---
 techlibs/common/synth.cc | 23 +++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/techlibs/common/synth.cc b/techlibs/common/synth.cc
index f604b67c9..7da9ba666 100644
--- a/techlibs/common/synth.cc
+++ b/techlibs/common/synth.cc
@@ -88,6 +88,10 @@ struct SynthPass : public ScriptPass {
 		log("        read/write collision\" (same result as setting the no_rw_check\n");
 		log("        attribute on all memories).\n");
 		log("\n");
+		log("    -inject filename\n");
+		log("        inject rules from the given file to complement the default\n");
+		log("        mapping library in the `techmap` step. this option can be\n");
+		log("        repeated.\n");
 		log("\n");
 		log("The following commands are executed by this synthesis command:\n");
 		help_script();
@@ -96,8 +100,8 @@ struct SynthPass : public ScriptPass {
 
 	string top_module, fsm_opts, memory_opts, abc;
 	bool autotop, flatten, noalumacc, nofsm, noabc, noshare, flowmap, booth;
-
 	int lut;
+	std::vector<std::string> techmap_inject;
 
 	void clear_flags() override
 	{
@@ -115,6 +119,7 @@ struct SynthPass : public ScriptPass {
 		flowmap = false;
 		booth = false;
 		abc = "abc";
+		techmap_inject.clear();
 	}
 
 	void execute(std::vector<std::string> args, RTLIL::Design *design) override
@@ -192,6 +197,10 @@ struct SynthPass : public ScriptPass {
 				memory_opts += " -no-rw-check";
 				continue;
 			}
+			if (args[argidx] == "-inject" && argidx + 1 < args.size()) {
+				techmap_inject.push_back(args[++argidx]);
+				continue;
+			}
 			break;
 		}
 		extra_args(args, argidx, design);
@@ -261,7 +270,17 @@ struct SynthPass : public ScriptPass {
 			run("opt -fast -full");
 			run("memory_map");
 			run("opt -full");
-			run("techmap");
+			if (help_mode) {
+				run("techmap", "                  (unless -inject)");	
+				run("techmap -map +/techmap.v -map <inject>", "  (if -inject)");
+			} else {
+				std::string techmap_opts;
+				if (!techmap_inject.empty())
+					techmap_opts += " -map +/techmap.v";
+				for (auto fn : techmap_inject)
+					techmap_opts += stringf(" -map %s", fn.c_str());
+				run("techmap" + techmap_opts);
+			}
 			if (help_mode) {
 				run("techmap -map +/gate2lut.v", "(if -noabc and -lut)");
 				run("clean; opt_lut", "           (if -noabc and -lut)");