279

patches/server/Improve-BlockPosition-inlining.patch

@@ -0,0 +1,60 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Techcable <Techcable@outlook.com>
+Date: Wed, 30 Nov 2016 20:56:58 -0600
+Subject: [PATCH] Improve BlockPosition inlining
+
+Normally the JVM can inline virtual getters by having two sets of code, one is the 'optimized' code and the other is the 'deoptimized' code.
+If a single type is used 99% of the time, then its worth it to inline, and to revert to 'deoptimized' the 1% of the time we encounter other types.
+But if two types are encountered commonly, then the JVM can't inline them both, and the call overhead remains.
+
+This scenario also occurs with BlockPos and MutableBlockPos.
+The variables in BlockPos are final, so MutableBlockPos can't modify them.
+MutableBlockPos fixes this by adding custom mutable variables, and overriding the getters to access them.
+
+This approach with utility methods that operate on MutableBlockPos and BlockPos.
+Specific examples are BlockPosition.up(), and World.isValidLocation().
+It makes these simple methods much slower than they need to be.
+
+This should result in an across the board speedup in anything that accesses blocks or does logic with positions.
+
+This is based upon conclusions drawn from inspecting the assenmbly generated bythe JIT compiler on my microbenchmarks.
+They had 'callq' (invoke) instead of 'mov' (get from memory) instructions.
+
+diff --git a/src/main/java/net/minecraft/core/Vec3i.java b/src/main/java/net/minecraft/core/Vec3i.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/net/minecraft/core/Vec3i.java
++++ b/src/main/java/net/minecraft/core/Vec3i.java
+@@ -0,0 +0,0 @@ public class Vec3i implements Comparable<Vec3i> {
+     }
+ 
+     @Override
+-    public boolean equals(Object object) {
++    public final boolean equals(Object object) { // Paper - Perf: Final for inline
+         return this == object || object instanceof Vec3i vec3i && this.getX() == vec3i.getX() && this.getY() == vec3i.getY() && this.getZ() == vec3i.getZ();
+     }
+ 
+     @Override
+-    public int hashCode() {
++    public final int hashCode() { // Paper - Perf: Final for inline
+         return (this.getY() + this.getZ() * 31) * 31 + this.getX();
+     }
+ 
+@@ -0,0 +0,0 @@ public class Vec3i implements Comparable<Vec3i> {
+         }
+     }
+ 
+-    public int getX() {
++    public final int getX() { // Paper - Perf: Final for inline
+         return this.x;
+     }
+ 
+-    public int getY() {
++    public final int getY() { // Paper - Perf: Final for inline
+         return this.y;
+     }
+ 
+-    public int getZ() {
++    public final int getZ() { // Paper - Perf: Final for inline
+         return this.z;
+     }
+