From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sun, 20 Sep 2020 16:10:49 -0700
Subject: [PATCH] Make sure inlined getChunkAt has inlined logic for loaded
 chunks

Tux did some profiling some time ago and showed that the
previous getChunkAt method which had inlined logic for loaded
chunks did get inlined, but the standard CPS.getChunkAt
method was not inlined.

diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
index 9536e127ff4d45ca59b74fe0f3dbde9a18c04f42..9afc0eaaca5ab7b6445d90ce53e31a6ae76f8848 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -350,7 +350,14 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
 
     @Override
     public final LevelChunk getChunk(int chunkX, int chunkZ) { // Paper - final to help inline
-        return (LevelChunk) this.getChunk(chunkX, chunkZ, ChunkStatus.FULL, true); // Paper - avoid a method jump
+        // Paper start - Perf: make sure loaded chunks get the inlined variant of this function
+        net.minecraft.server.level.ServerChunkCache cps = ((ServerLevel)this).getChunkSource();
+        LevelChunk ifLoaded = cps.getChunkAtIfLoadedImmediately(chunkX, chunkZ);
+        if (ifLoaded != null) {
+            return ifLoaded;
+        }
+        return (LevelChunk) cps.getChunk(chunkX, chunkZ, ChunkStatus.FULL, true); // Paper - avoid a method jump
+        // Paper end - Perf: make sure loaded chunks get the inlined variant of this function
     }
 
     // Paper start - if loaded