From d28f97e9da2d168406a2758a4b7cfd3d65f94159 Mon Sep 17 00:00:00 2001
From: Robert O'Callahan <rocallahan@google.com>
Date: Thu, 9 Oct 2025 23:40:47 +0000
Subject: [PATCH] Remove YOSYS_USE_STICKY_IDS

---
 kernel/rtlil.cc |  4 ----
 kernel/rtlil.h  | 23 -----------------------
 2 files changed, 27 deletions(-)

diff --git a/kernel/rtlil.cc b/kernel/rtlil.cc
index 670b61afd..c6358729a 100644
--- a/kernel/rtlil.cc
+++ b/kernel/rtlil.cc
@@ -41,10 +41,6 @@ std::unordered_map<std::string_view, int> RTLIL::IdString::global_id_index_;
 std::vector<uint32_t> RTLIL::IdString::global_refcount_storage_;
 std::vector<int> RTLIL::IdString::global_free_idx_list_;
 #endif
-#ifdef YOSYS_USE_STICKY_IDS
-int RTLIL::IdString::last_created_idx_[8];
-int RTLIL::IdString::last_created_idx_ptr_;
-#endif
 
 #define X(_id) const RTLIL::IdString RTLIL::IDInternal::_id(RTLIL::StaticId::_id);
 #include "kernel/constids.inc"
diff --git a/kernel/rtlil.h b/kernel/rtlil.h
index fbf9292b3..556f936e9 100644
--- a/kernel/rtlil.h
+++ b/kernel/rtlil.h
@@ -145,7 +145,6 @@ struct RTLIL::IdString
 
 	#undef YOSYS_XTRACE_GET_PUT
 	#undef YOSYS_SORT_ID_FREE_LIST
-	#undef YOSYS_USE_STICKY_IDS
 	#undef YOSYS_NO_IDS_REFCNT
 
 	// the global id string cache
@@ -169,11 +168,6 @@ struct RTLIL::IdString
 	static std::vector<int> global_free_idx_list_;
 #endif
 
-#ifdef YOSYS_USE_STICKY_IDS
-	static int last_created_idx_ptr_;
-	static int last_created_idx_[8];
-#endif
-
 	static inline void xtrace_db_dump()
 	{
 	#ifdef YOSYS_XTRACE_GET_PUT
@@ -189,14 +183,6 @@ struct RTLIL::IdString
 
 	static inline void checkpoint()
 	{
-	#ifdef YOSYS_USE_STICKY_IDS
-		last_created_idx_ptr_ = 0;
-		for (int i = 0; i < 8; i++) {
-			if (last_created_idx_[i])
-				put_reference(last_created_idx_[i]);
-			last_created_idx_[i] = 0;
-		}
-	#endif
 	#ifdef YOSYS_SORT_ID_FREE_LIST
 		std::sort(global_free_idx_list_.begin(), global_free_idx_list_.end(), std::greater<int>());
 	#endif
@@ -273,15 +259,6 @@ struct RTLIL::IdString
 			log("#X# GET-BY-NAME '%s' (index %d, refcount %u)\n", global_id_storage_.at(idx).buf, idx, global_refcount_storage_.at(idx));
 	#endif
 
-	#ifdef YOSYS_USE_STICKY_IDS
-		// Avoid Create->Delete->Create pattern
-		if (last_created_idx_[last_created_idx_ptr_])
-			put_reference(last_created_idx_[last_created_idx_ptr_]);
-		last_created_idx_[last_created_idx_ptr_] = idx;
-		get_reference(last_created_idx_[last_created_idx_ptr_]);
-		last_created_idx_ptr_ = (last_created_idx_ptr_ + 1) & 7;
-	#endif
-
 		return idx;
 	}