From fb93b9d81f04f47e868ca1b05e225e2f790b3861 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=CE=B6eh=20Matt?= <5415177+ZehMatt@users.noreply.github.com>
Date: Mon, 13 Dec 2021 17:05:01 +0200
Subject: [PATCH] Use fold expressions to enable potential simd optimizations

---
 src/openrct2/core/BitSet.hpp | 38 +++++++++++++-----------------------
 1 file changed, 14 insertions(+), 24 deletions(-)

diff --git a/src/openrct2/core/BitSet.hpp b/src/openrct2/core/BitSet.hpp
index 9256010a96..988af874db 100644
--- a/src/openrct2/core/BitSet.hpp
+++ b/src/openrct2/core/BitSet.hpp
@@ -404,14 +404,7 @@ namespace OpenRCT2
         constexpr BitSet operator^(const BitSet& other) const noexcept
         {
             BitSet res = *this;
-            for (size_t i = 0; i < _data.size(); i++)
-            {
-                res._data[i] ^= other._data[i];
-            }
-            if constexpr (RequiresTrim)
-            {
-                res.Trim();
-            }
+            ApplyOp<std::bit_xor<BlockType>>(res, other, std::make_index_sequence<BlockCount>{});
             return res;
         }
 
@@ -424,14 +417,7 @@ namespace OpenRCT2
         constexpr BitSet operator|(const BitSet& other) const noexcept
         {
             BitSet res = *this;
-            for (size_t i = 0; i < _data.size(); i++)
-            {
-                res._data[i] |= other._data[i];
-            }
-            if constexpr (RequiresTrim)
-            {
-                res.Trim();
-            }
+            ApplyOp<std::bit_or<BlockType>>(res, other, std::make_index_sequence<BlockCount>{});
             return res;
         }
 
@@ -444,14 +430,7 @@ namespace OpenRCT2
         constexpr BitSet operator&(const BitSet& other) const noexcept
         {
             BitSet res = *this;
-            for (size_t i = 0; i < _data.size(); i++)
-            {
-                res._data[i] &= other._data[i];
-            }
-            if constexpr (RequiresTrim)
-            {
-                res.Trim();
-            }
+            ApplyOp<std::bit_and<BlockType>>(res, other, std::make_index_sequence<BlockCount>{});
             return res;
         }
 
@@ -500,6 +479,17 @@ namespace OpenRCT2
         }
 
     private:
+        template<typename TOperator, size_t... TIndex>
+        void ApplyOp(BitSet& dst, const BitSet& src, std::index_sequence<TIndex...>) const
+        {
+            TOperator op{};
+            ((dst._data[TIndex] = op(dst._data[TIndex], src._data[TIndex])), ...);
+            if constexpr (RequiresTrim)
+            {
+                dst.Trim();
+            }
+        }
+
         static constexpr size_t ComputeBlockIndex(size_t idx) noexcept
         {
             if constexpr (BlockCount == 1)