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 68cee32833a3d683852e67e3727d62b84fa60cc4..a1731f09e724794be90dbf47e1d463a10cdb3052 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -351,7 +351,14 @@ 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