From 030e5ec43851569fc0e7991a6672cebdae295b48 Mon Sep 17 00:00:00 2001
From: Robert O'Callahan <rocallahan@google.com>
Date: Tue, 2 Sep 2025 03:01:11 +0000
Subject: [PATCH] Make IdString hashing take a reference to the IdString
 instead of copying it

---
 kernel/rtlil.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/rtlil.h b/kernel/rtlil.h
index ea358d83b..c81a0c00a 100644
--- a/kernel/rtlil.h
+++ b/kernel/rtlil.h
@@ -430,10 +430,10 @@ namespace hashlib {
 		static inline bool cmp(const RTLIL::IdString &a, const RTLIL::IdString &b) {
 			return a == b;
 		}
-		[[nodiscard]] static inline Hasher hash(const RTLIL::IdString id) {
+		[[nodiscard]] static inline Hasher hash(const RTLIL::IdString &id) {
 			return id.hash_top();
 		}
-		[[nodiscard]] static inline Hasher hash_into(const RTLIL::IdString id, Hasher h) {
+		[[nodiscard]] static inline Hasher hash_into(const RTLIL::IdString &id, Hasher h) {
 			return id.hash_into(h);
 		}
 	};