From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 3 Mar 2016 02:07:55 -0600
Subject: [PATCH] Optimize isValidLocation, getType and getBlockData for inling

Hot methods, so reduce # of instructions for the method.

Move is valid location test to the BlockPosition class so that it can access local variables.

Replace all calls to the new place to the unnecessary forward.

Optimize getType and getBlockData to manually inline and optimize the calls

diff --git a/src/main/java/net/minecraft/server/BaseBlockPosition.java b/src/main/java/net/minecraft/server/BaseBlockPosition.java
index d55e180d..679d5504 100644
--- a/src/main/java/net/minecraft/server/BaseBlockPosition.java
+++ b/src/main/java/net/minecraft/server/BaseBlockPosition.java
@@ -0,0 +0,0 @@ public class BaseBlockPosition implements Comparable<BaseBlockPosition> {
     private final int a;
     private final int b;
     private final int c;
+    // Paper start
+    public boolean isValidLocation() {
+        return a >= -30000000 && c >= -30000000 && a < 30000000 && c < 30000000 && b >= 0 && b < 256;
+    }
+    public boolean isInvalidYLocation() {
+        return b < 0 || b >= 256;
+    }
+    // Paper end
 
     public BaseBlockPosition(int i, int j, int k) {
         this.a = i;
diff --git a/src/main/java/net/minecraft/server/BlockPosition.java b/src/main/java/net/minecraft/server/BlockPosition.java
index 67b476b2..008ed206 100644
--- a/src/main/java/net/minecraft/server/BlockPosition.java
+++ b/src/main/java/net/minecraft/server/BlockPosition.java
@@ -0,0 +0,0 @@ public class BlockPosition extends BaseBlockPosition {
         protected int b;
         protected int c;
         protected int d;
+        // Paper start
+        @Override
+        public boolean isValidLocation() {
+            return b >= -30000000 && d >= -30000000 && b < 30000000 && d < 30000000 && c >= 0 && c < 256;
+        }
+        @Override
+        public boolean isInvalidYLocation() {
+            return c < 0 || c >= 256;
+        }
+        // Paper end
 
         public MutableBlockPosition() {
             this(0, 0, 0);
diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
index 84a88056..172d00bd 100644
--- a/src/main/java/net/minecraft/server/Chunk.java
+++ b/src/main/java/net/minecraft/server/Chunk.java
@@ -0,0 +0,0 @@ public class Chunk {
         return this.a(i, j, k).c();
     }
 
-    public IBlockData getBlockData(BlockPosition blockposition) {
-        return this.a(blockposition.getX(), blockposition.getY(), blockposition.getZ());
+    // Paper start - Optimize getBlockData to reduce instructions
+    public final IBlockData getBlockData(final BlockPosition pos) {
+        return getBlockData(pos.getX(), pos.getY(), pos.getZ());
+    }
+
+    public final IBlockData getBlockData(final int x, final int y, final int z) {
+        // Method body / logic copied from below
+        final int i = y >> 4;
+        if (y >= 0 && i < this.sections.length && this.sections[i] != null) {
+            // Inlined ChunkSection.getType() and DataPaletteBlock.a(int,int,int)
+            return this.sections[i].blockIds.a((y & 15) << 8 | (z & 15) << 4 | x & 15);
+        }
+        return Blocks.AIR.getBlockData();
     }
 
     public IBlockData a(final int i, final int j, final int k) {
+        return getBlockData(i, j, k);
+    }
+
+    public IBlockData unused(final int i, final int j, final int k) {
+    // Paper end
         if (this.world.N() == WorldType.DEBUG_ALL_BLOCK_STATES) {
             IBlockData iblockdata = null;
 
diff --git a/src/main/java/net/minecraft/server/ChunkSection.java b/src/main/java/net/minecraft/server/ChunkSection.java
index 3d784d0d..afdc4a77 100644
--- a/src/main/java/net/minecraft/server/ChunkSection.java
+++ b/src/main/java/net/minecraft/server/ChunkSection.java
@@ -0,0 +0,0 @@ public class ChunkSection {
     private final int yPos;
     private int nonEmptyBlockCount;
     private int tickingBlockCount;
-    private final DataPaletteBlock blockIds;
+    final DataPaletteBlock blockIds; // Paper - package
     private NibbleArray emittedLight;
     private NibbleArray skyLight;
 
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 9339bf83..a20c9810 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
         return this.getType(blockposition1);
     }
 
-    private boolean isValidLocation(BlockPosition blockposition) {
-        return !this.E(blockposition) && blockposition.getX() >= -30000000 && blockposition.getZ() >= -30000000 && blockposition.getX() < 30000000 && blockposition.getZ() < 30000000;
+    private static boolean isValidLocation(BlockPosition blockposition) { // Paper - unused but incase reflection / future uses
+        return blockposition.isValidLocation(); // Paper
     }
 
-    private boolean E(BlockPosition blockposition) {
-        return blockposition.getY() < 0 || blockposition.getY() >= 256;
+    private static boolean E(BlockPosition blockposition) { // Paper - unused but incase reflection / future uses
+        return blockposition.isInvalidYLocation(); // Paper
     }
 
     public boolean isEmpty(BlockPosition blockposition) {
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
             return true;
         }
         // CraftBukkit end
-        if (this.E(blockposition)) {
+        if (blockposition.isInvalidYLocation()) { // Paper
             return false;
         } else if (!this.isClientSide && this.worldData.getType() == WorldType.DEBUG_ALL_BLOCK_STATES) {
             return false;
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
     // Paper start - test if meets light level, return faster
     // logic copied from below
     public boolean isLightLevel(BlockPosition blockposition, int level) {
-        if (isValidLocation(blockposition)) {
+        if (blockposition.isValidLocation()) {
             if (this.getType(blockposition).f()) {
                 if (this.c(blockposition.up(), false) >= level) {
                     return true;
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
             blockposition = new BlockPosition(blockposition.getX(), 0, blockposition.getZ());
         }
 
-        if (!this.isValidLocation(blockposition)) {
+        if (!blockposition.isValidLocation()) { // Paper
             return enumskyblock.c;
         } else if (!this.isLoaded(blockposition)) {
             return enumskyblock.c;
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
     }
 
     public void a(EnumSkyBlock enumskyblock, BlockPosition blockposition, int i) {
-        if (this.isValidLocation(blockposition)) {
+        if (blockposition.isValidLocation()) { // Paper
             if (this.isLoaded(blockposition)) {
                 Chunk chunk = this.getChunkAtWorldCoords(blockposition);
 
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
     // Paper start - reduces need to do isLoaded before getType
     public IBlockData getTypeIfLoaded(BlockPosition blockposition) {
         // CraftBukkit start - tree generation
+        final int x = blockposition.getX();
+        final int y = blockposition.getY();
+        final int z = blockposition.getZ();
         if (captureTreeGeneration) {
-            Iterator<BlockState> it = capturedBlockStates.iterator();
-            while (it.hasNext()) {
-                BlockState previous = it.next();
-                if (previous.getX() == blockposition.getX() && previous.getY() == blockposition.getY() && previous.getZ() == blockposition.getZ()) {
-                    return CraftMagicNumbers.getBlock(previous.getTypeId()).fromLegacyData(previous.getRawData());
-                }
+            final IBlockData previous = getCapturedBlockType(x, y, z);
+            if (previous != null) {
+                return previous;
             }
         }
         // CraftBukkit end
-        Chunk chunk = this.getChunkIfLoaded(blockposition);
+        Chunk chunk = ((ChunkProviderServer) this.chunkProvider).getChunkIfLoaded(x >> 4, z >> 4);
         if (chunk != null) {
-            return this.isValidLocation(blockposition) ? chunk.getBlockData(blockposition) : Blocks.AIR.getBlockData();
+            return chunk.getBlockData(x, y, z);
         }
         return null;
     }
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
 
     public IBlockData getType(BlockPosition blockposition) {
         // CraftBukkit start - tree generation
+        // Paper start - optimize getType lookup to reduce instructions - getBlockData already enforces valid Y, move tree out
+        final int x = blockposition.getX();
+        final int y = blockposition.getY();
+        final int z = blockposition.getZ();
         if (captureTreeGeneration) {
-            Iterator<BlockState> it = capturedBlockStates.iterator();
-            while (it.hasNext()) {
-                BlockState previous = it.next();
-                if (previous.getX() == blockposition.getX() && previous.getY() == blockposition.getY() && previous.getZ() == blockposition.getZ()) {
-                    return CraftMagicNumbers.getBlock(previous.getTypeId()).fromLegacyData(previous.getRawData());
-                }
+            final IBlockData previous = getCapturedBlockType(x, y, z);
+            if (previous != null) {
+                return previous;
             }
         }
         // CraftBukkit end
-        if (this.E(blockposition)) {
-            return Blocks.AIR.getBlockData();
-        } else {
-            Chunk chunk = this.getChunkAtWorldCoords(blockposition);
+        return this.chunkProvider.getChunkAt(x >> 4, z >> 4).getBlockData(x, y, z);
+        // Paper end
+    }
 
-            return chunk.getBlockData(blockposition);
+    // Paper start
+    private IBlockData getCapturedBlockType(int x, int y, int z) {
+        Iterator<BlockState> it = capturedBlockStates.iterator();
+        while (it.hasNext()) {
+            BlockState previous = it.next();
+            if (previous.getX() == x && previous.getY() == y && previous.getZ() == z) {
+                return CraftMagicNumbers.getBlock(previous.getTypeId()).fromLegacyData(previous.getRawData());
+            }
         }
+        return null;
     }
+    // Paper end
 
     public boolean D() {
         return this.L < 4;
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
     public Map<BlockPosition, TileEntity> capturedTileEntities = Maps.newHashMap();
     @Nullable
     public TileEntity getTileEntity(BlockPosition blockposition) {
-        if (this.E(blockposition)) {
+        if (blockposition.isInvalidYLocation()) { // Paper
             return null;
         } else {
             // CraftBukkit start
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
     }
 
     public void setTileEntity(BlockPosition blockposition, @Nullable TileEntity tileentity) {
-        if (!this.E(blockposition)) {
+        if (!blockposition.isInvalidYLocation()) {
             if (tileentity != null && !tileentity.y()) {
             // CraftBukkit start
             if (captureBlockStates) {
@@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {
     }
 
     public boolean d(BlockPosition blockposition, boolean flag) {
-        if (this.E(blockposition)) {
+        if (blockposition.isInvalidYLocation()) { // Paper
             return false;
         } else {
             Chunk chunk = this.chunkProvider.getLoadedChunkAt(blockposition.getX() >> 4, blockposition.getZ() >> 4);
--