From d96461e40c53583a0d63a8c4f11da09a29a238a1 Mon Sep 17 00:00:00 2001
From: "Emil J. Tywoniak" <emil@tywoniak.eu>
Date: Mon, 15 Jun 2026 17:41:21 +0200
Subject: [PATCH] twine: fix off-by-one static twine error

---
 kernel/rtlil.cc |  6 ++++++
 kernel/twine.h  | 23 ++++++++++++++++++++---
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/kernel/rtlil.cc b/kernel/rtlil.cc
index b31aebc39..2ec4abe92 100644
--- a/kernel/rtlil.cc
+++ b/kernel/rtlil.cc
@@ -2003,6 +2003,12 @@ namespace {
 
 		int param_bool(IdString name)
 		{
+			std::cout << name.str() << "\n";
+			std::cout << "get\n";
+			for (auto& [key, val] : cell->parameters) {
+				std::cout << key.str() << " = ";
+				std::cout << val.as_string() << "\n";
+			}
 			int v = param(name);
 			if (GetSize(cell->parameters.at(name)) > 32)
 				error(__LINE__);
diff --git a/kernel/twine.h b/kernel/twine.h
index 362c93ad6..d602afdfa 100644
--- a/kernel/twine.h
+++ b/kernel/twine.h
@@ -68,7 +68,7 @@ constexpr TwineRef TWINE_PUBLIC_BIT = TwineRef(1LLU << 62);
 constexpr TwineRef TWINE_TAG_MASK = TWINE_LOCAL_BIT | TWINE_PUBLIC_BIT;
 
 enum : short {
-	STATIC_TWINE_BEGIN = 0,
+	// STATIC_TWINE_BEGIN = 0,
 #define X(N) IDX_##N,
 #include "kernel/constids.inc"
 #undef X
@@ -168,10 +168,15 @@ struct TwinePool {
 
 	const Twine& operator[] (TwineRef ref) const {
 		ref = twine_untag(ref);
-		if (ref < STATIC_TWINE_END)
+		if (ref < STATIC_TWINE_END) {
+			if (yosys_xtrace)
+				std::cout << "#X# accessing " << (size_t)ref << " from globals\n";
 			return globals_[ref];
-		else
+		} else {
+			if (yosys_xtrace)
+				std::cout << "#X# accessing " << (size_t)ref << " from colony of size " << backing.size() << "\n";
 			return backing[ref - STATIC_TWINE_END];
+		}
 	}
 
 	void dump(TwineRef ref, std::ostream& os = std::cout) const {
@@ -289,12 +294,24 @@ struct TwinePool {
 		}
 
 		if (auto it = index.find(t); it != index.end()) {
+			if (yosys_xtrace) {
+				std::cout << "#X# add_inner found ";
+				dump(*it);
+				std::cout << "\n";
+				std::cout << "#X# as integer " << *it << "\n";
+			}
 			return *it;
 		}
 
 		auto colony_it = backing.insert(std::move(t));
 		TwineRef ref = STATIC_TWINE_END + backing.get_index(colony_it);
 		index.insert(ref);
+		if (yosys_xtrace) {
+			std::cout << "#X# add_inner added ";
+			dump(ref);
+			std::cout << "\n";
+			std::cout << "#X# as integer " << ref << "\n";
+		}
 		return ref;
 	}