From fce46d2a53d886ba1d72e232ce755bb44e16920c Mon Sep 17 00:00:00 2001
From: Akash Levy <akashlevy@gmail.com>
Date: Sat, 15 Jun 2024 14:18:33 -0700
Subject: [PATCH] Add better Yosys/Verific name aliasing and reenable dffe opt

---
 frontends/verific/verific.cc | 4 +++-
 kernel/yosys.cc              | 1 +
 kernel/yosys_common.h        | 1 +
 passes/opt/opt_dff.cc        | 2 +-
 4 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/frontends/verific/verific.cc b/frontends/verific/verific.cc
index b4a83518c..e45d4de67 100644
--- a/frontends/verific/verific.cc
+++ b/frontends/verific/verific.cc
@@ -207,7 +207,9 @@ bool is_blackbox(Netlist *nl)
 
 RTLIL::IdString VerificImporter::new_verific_id(Verific::DesignObj *obj)
 {
-	std::string s = stringf("$%s$%d", obj->Name(), autoidx++);
+	std::string s = stringf("$%s", obj->Name());
+	if (seen_ids.count(s)) s += stringf("$%d", autoidx++);
+	seen_ids.insert(s);
 	return s;
 }
 
diff --git a/kernel/yosys.cc b/kernel/yosys.cc
index b8e06f2db..aab0b191c 100644
--- a/kernel/yosys.cc
+++ b/kernel/yosys.cc
@@ -79,6 +79,7 @@ YOSYS_NAMESPACE_BEGIN
 
 int autoidx = 1;
 int yosys_xtrace = 0;
+std::set<string> seen_ids;
 RTLIL::Design *yosys_design = NULL;
 CellTypes yosys_celltypes;
 
diff --git a/kernel/yosys_common.h b/kernel/yosys_common.h
index 9f1bc2f58..22aeafafa 100644
--- a/kernel/yosys_common.h
+++ b/kernel/yosys_common.h
@@ -348,6 +348,7 @@ inline int GetSize(RTLIL::Wire *wire);
 
 extern int autoidx;
 extern int yosys_xtrace;
+extern std::set<string> seen_ids;
 
 RTLIL::IdString new_id(std::string file, int line, std::string func);
 RTLIL::IdString new_id_suffix(std::string file, int line, std::string func, std::string suffix);
diff --git a/passes/opt/opt_dff.cc b/passes/opt/opt_dff.cc
index f0a22fd61..b77be4515 100644
--- a/passes/opt/opt_dff.cc
+++ b/passes/opt/opt_dff.cc
@@ -884,7 +884,7 @@ struct OptDffPass : public Pass {
 	{
 		log_header(design, "Executing OPT_DFF pass (perform DFF optimizations).\n");
 		OptDffOptions opt;
-		opt.nodffe = true; // SILIMATE: DISABLE DFFE PASS BECAUSE IT BREAKS THE DESIGN
+		opt.nodffe = false;
 		opt.nosdff = false;
 		opt.simple_dffe = false;
 		opt.keepdc = false;