From 159e7cc2983e3d026fa8c5187252bb890a04b96f Mon Sep 17 00:00:00 2001
From: Eddie Hung <eddie@fpgeh.com>
Date: Fri, 26 Apr 2019 11:14:33 -0700
Subject: [PATCH] Add -undef option to equiv_opt, passed to equiv_induct

---
 passes/equiv/equiv_opt.cc | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/passes/equiv/equiv_opt.cc b/passes/equiv/equiv_opt.cc
index e5dda9c24..3596dfd7b 100644
--- a/passes/equiv/equiv_opt.cc
+++ b/passes/equiv/equiv_opt.cc
@@ -44,7 +44,10 @@ struct EquivOptPass:public ScriptPass
 		log("        useful for handling architecture-specific primitives.\n");
 		log("\n");
 		log("    -assert\n");
-		log("        produce an error if the circuits are not equivalent\n");
+		log("        produce an error if the circuits are not equivalent.\n");
+		log("\n");
+		log("    -undef\n");
+		log("        enable modelling of undef states during equiv_induct.\n");
 		log("\n");
 		log("The following commands are executed by this verification command:\n");
 		help_script();
@@ -52,13 +55,14 @@ struct EquivOptPass:public ScriptPass
 	}
 
 	std::string command, techmap_opts;
-	bool assert;
+	bool assert, undef;
 
 	void clear_flags() YS_OVERRIDE
 	{
 		command = "";
 		techmap_opts = "";
 		assert = false;
+		undef = false;
 	}
 
 	void execute(std::vector < std::string > args, RTLIL::Design * design) YS_OVERRIDE
@@ -84,6 +88,10 @@ struct EquivOptPass:public ScriptPass
 				assert = true;
 				continue;
 			}
+			if (args[argidx] == "-undef") {
+				undef = true;
+				continue;
+			}
 			break;
 		}
 
@@ -139,7 +147,12 @@ struct EquivOptPass:public ScriptPass
 
 		if (check_label("prove")) {
 			run("equiv_make gold gate equiv");
-			run("equiv_induct equiv");
+			if (help_mode)
+				run("equiv_induct [-undef] equiv");
+			else if (undef)
+				run("equiv_induct -undef equiv");
+			else
+				run("equiv_induct equiv");
 			if (help_mode)
 				run("equiv_status [-assert] equiv");
 			else if (assert)
-- 
2.30.2