cache: some work on the interpreter

cache/src/main/java/net/runelite/cache/script/interpreter/Frame.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import net.runelite.cache.definitions.ScriptDefinition;
+
+public class Frame
+{
+	private final Interpreter interpreter;
+	private final ScriptDefinition script;
+	private final Stack intStack;
+	private final Stack stringStack;
+
+	private boolean running = true;
+	int pc;
+
+	public Frame(Interpreter interpreter, ScriptDefinition script)
+	{
+		this.interpreter = interpreter;
+		this.script = script;
+		this.intStack = new Stack();
+		this.stringStack = new Stack();
+	}
+
+	public Frame(Interpreter interpreter, Frame other)
+	{
+		this.interpreter = interpreter;
+		this.script = other.script;
+		this.intStack = new Stack(other.intStack);
+		this.stringStack = new Stack(other.stringStack);
+		this.pc = other.pc;
+	}
+
+	public Stack getIntStack()
+	{
+		return intStack;
+	}
+
+	public Stack getStringStack()
+	{
+		return stringStack;
+	}
+
+	public ScriptDefinition getScript()
+	{
+		return script;
+	}
+
+	public Frame dup()
+	{
+		Frame frame = new Frame(interpreter, this);
+		interpreter.addFrame(this);
+		return frame;
+	}
+
+	public boolean isRunning()
+	{
+		return running;
+	}
+
+	public void stop()
+	{
+		running = false;
+	}
+
+	public void jump(int offset)
+	{
+		pc += offset + 1;
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/GenericInstructionHandler.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import net.runelite.cache.script.Instruction;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class GenericInstructionHandler extends InstructionHandler
+{
+	private static final Logger logger = LoggerFactory.getLogger(GenericInstructionHandler.class);
+
+	@Override
+	public void execute(Frame frame, InstructionContext ctx)
+	{
+		Instruction i = ctx.getScriptInstruction().getInstruction();
+		Stack istack = frame.getIntStack();
+		Stack sstack = frame.getStringStack();
+
+		int ipops = i.getIntStackPops();
+		for (int j = 0; j < ipops; ++j)
+		{
+			StackContext value = istack.pop();
+			ctx.popsInt(value);
+			value.poppedBy(ctx);
+		}
+
+		int spops = i.getStringStackPops();
+		for (int j = 0; j < spops; ++j)
+		{
+			StackContext value = sstack.pop();
+			ctx.popsString(value);
+			value.poppedBy(ctx);
+		}
+
+		int ipushes = i.getIntStackPushes();
+		for (int j = 0; j < ipushes; ++j)
+		{
+			StackContext sctx = new StackContext(ctx, null);
+			istack.push(sctx);
+			ctx.pushesInt(sctx);
+		}
+
+		int spushes = i.getStringStackPushes();
+		for (int j = 0; j < spushes; ++j)
+		{
+			StackContext sctx = new StackContext(ctx, null);
+			sstack.push(sctx);
+			ctx.pushesString(sctx);
+		}
+
+		if (ipushes > 0 || spushes > 0)
+		{
+			logger.debug("Executed instruction {} with {}/{} pushes!", i, ipushes, spushes);
+		}
+	}
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/InstructionContext.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class InstructionContext
+{
+	private final ScriptInstruction scriptInstruction;
+
+	private final List<StackContext> ipops = new ArrayList<>();
+	private final List<StackContext> spops = new ArrayList<>();
+	private final List<StackContext> ipushes = new ArrayList<>();
+	private final List<StackContext> spushes = new ArrayList<>();
+
+	public InstructionContext(ScriptInstruction scriptInstruction)
+	{
+		this.scriptInstruction = scriptInstruction;
+	}
+
+	public ScriptInstruction getScriptInstruction()
+	{
+		return scriptInstruction;
+	}
+
+	public void popsInt(StackContext... ctx)
+	{
+		for (StackContext s : ctx)
+		{
+			ipops.add(s);
+		}
+	}
+
+	public void popsString(StackContext... ctx)
+	{
+		for (StackContext s : ctx)
+		{
+			spops.add(s);
+		}
+	}
+
+	public void pushesInt(StackContext... ctx)
+	{
+		for (StackContext s : ctx)
+		{
+			ipushes.add(s);
+		}
+	}
+
+	public void pushesString(StackContext... ctx)
+	{
+		for (StackContext s : ctx)
+		{
+			spushes.add(s);
+		}
+
+	}
+
+	public List<StackContext> getIpops()
+	{
+		return ipops;
+	}
+
+	public List<StackContext> getSpops()
+	{
+		return spops;
+	}
+
+	public List<StackContext> getIpushes()
+	{
+		return ipushes;
+	}
+
+	public List<StackContext> getSpushes()
+	{
+		return spushes;
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/InstructionHandler.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+public abstract class InstructionHandler
+{
+	public abstract void execute(Frame frame, InstructionContext ctx);
+}

cache/src/main/java/net/runelite/cache/script/interpreter/InstructionHandlers.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import java.util.HashMap;
+import java.util.Map;
+import net.runelite.cache.script.Opcodes;
+import net.runelite.cache.script.interpreter.instructions.If_ICmpEQ;
+import net.runelite.cache.script.interpreter.instructions.If_ICmpGE;
+import net.runelite.cache.script.interpreter.instructions.If_ICmpGT;
+import net.runelite.cache.script.interpreter.instructions.If_ICmpLE;
+import net.runelite.cache.script.interpreter.instructions.If_ICmpLT;
+import net.runelite.cache.script.interpreter.instructions.If_ICmpNE;
+import net.runelite.cache.script.interpreter.instructions.Jump;
+import net.runelite.cache.script.interpreter.instructions.LoadInt;
+import net.runelite.cache.script.interpreter.instructions.Return;
+
+public class InstructionHandlers
+{
+	private static final Map<Integer, InstructionHandler> handlers = new HashMap<>();
+
+	static
+	{
+		init();
+	}
+
+	private static void init()
+	{
+		add(Opcodes.LOAD_INT, new LoadInt());
+		add(Opcodes.JUMP, new Jump());
+		add(Opcodes.IF_ICMPNE, new If_ICmpNE());
+		add(Opcodes.IF_ICMPEQ, new If_ICmpEQ());
+		add(Opcodes.IF_ICMPLT, new If_ICmpLT());
+		add(Opcodes.IF_ICMPGT, new If_ICmpGT());
+		add(Opcodes.IF_ICMPLE, new If_ICmpLE());
+		add(Opcodes.IF_ICMPGE, new If_ICmpGE());
+		add(Opcodes.RETURN, new Return());
+	}
+
+	private static void add(int opcode, InstructionHandler handler)
+	{
+		assert handlers.containsKey(opcode) == false;
+		handlers.put(opcode, handler);
+	}
+
+	public static InstructionHandler find(int opcode)
+	{
+		return handlers.get(opcode);
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/Interpreter.java

@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import java.util.ArrayDeque;
+import java.util.Queue;
+import net.runelite.cache.definitions.ScriptDefinition;
+import net.runelite.cache.script.Instruction;
+import net.runelite.cache.script.Instructions;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class Interpreter
+{
+	private static final Logger logger = LoggerFactory.getLogger(Interpreter.class);
+
+	private final Queue<Frame> frames = new ArrayDeque<>();
+	private final GenericInstructionHandler genericInstructionHandler = new GenericInstructionHandler();
+
+	public void run(ScriptDefinition script)
+	{
+		Instructions.init();
+
+		Frame frame = new Frame(this, script);
+		frames.add(frame);
+
+		int count = 0;
+
+		while (!frames.isEmpty())
+		{
+			frame = frames.remove();
+			run(frame);
+			++count;
+		}
+
+		logger.info("Processed {} frames", count);
+	}
+
+	private void run(Frame frame)
+	{
+		ScriptDefinition script = frame.getScript();
+
+		int[] instructions = script.getInstructions();
+		int[] iops = script.getIntOperands();
+		String[] sops = script.getStringOperands();
+
+		while (frame.isRunning())
+		{
+			if (frame.pc >= instructions.length)
+			{
+				throw new RuntimeException("PC went past end of instructions - maybe missing return");
+			}
+
+			int opcode = instructions[frame.pc];
+			int iop = iops[frame.pc];
+			String sop = sops[frame.pc];
+
+			Instruction i = Instructions.find(opcode);
+			if (i == null)
+			{
+				throw new RuntimeException("Unknown instruction " + opcode + " in script at pc " + frame.pc);
+			}
+
+			ScriptInstruction scriptInstruction = new ScriptInstruction(frame.pc, i, iop, sop);
+			InstructionContext ctx = new InstructionContext(scriptInstruction);
+
+			InstructionHandler handler = InstructionHandlers.find(opcode);
+			if (handler == null)
+			{
+				handler = genericInstructionHandler;
+			}
+
+			int old = frame.pc;
+
+			handler.execute(frame, ctx);
+
+			if (old == frame.pc)
+			{
+				// not a jump
+				++frame.pc;
+			}
+		}
+	}
+
+	public void addFrame(Frame frame)
+	{
+		frames.add(frame);
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/ScriptInstruction.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import net.runelite.cache.script.Instruction;
+
+/**
+ * an instruction in a script
+ *
+ * @author Adam
+ */
+public class ScriptInstruction
+{
+	private final int pc;
+	private final Instruction instruction;
+	private final int iop;
+	private final String sop;
+
+	public ScriptInstruction(int pc, Instruction instruction, int iop, String sop)
+	{
+		this.pc = pc;
+		this.instruction = instruction;
+		this.iop = iop;
+		this.sop = sop;
+	}
+
+	public int getPc()
+	{
+		return pc;
+	}
+
+	public Instruction getInstruction()
+	{
+		return instruction;
+	}
+
+	public int getIop()
+	{
+		return iop;
+	}
+
+	public String getSop()
+	{
+		return sop;
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/Stack.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Stack
+{
+	private final List<StackContext> stack = new ArrayList<>();
+
+	public Stack()
+	{
+	}
+
+	public Stack(Stack other)
+	{
+		stack.addAll(other.stack);
+	}
+
+	public void push(StackContext ctx)
+	{
+		stack.add(ctx);
+	}
+
+	public StackContext pop()
+	{
+		if (stack.isEmpty())
+		{
+			throw new RuntimeException("stack underflow");
+		}
+
+		return stack.remove(stack.size() - 1);
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/StackContext.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class StackContext
+{
+	private final InstructionContext pushed;
+	private final List<InstructionContext> popped = new ArrayList<>();
+	private final Object value;
+
+	public StackContext(InstructionContext pushed, Object value)
+	{
+		assert value == null || value instanceof String || value instanceof Integer;
+		this.pushed = pushed;
+		this.value = value;
+	}
+
+	public void poppedBy(InstructionContext ctx)
+	{
+		popped.add(ctx);
+	}
+
+	public InstructionContext getPushed()
+	{
+		return pushed;
+	}
+
+	public List<InstructionContext> getPopped()
+	{
+		return popped;
+	}
+
+	public Object getValue()
+	{
+		return value;
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/If.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+import net.runelite.cache.script.interpreter.Frame;
+import net.runelite.cache.script.interpreter.InstructionContext;
+import net.runelite.cache.script.interpreter.InstructionHandler;
+import net.runelite.cache.script.interpreter.Stack;
+import net.runelite.cache.script.interpreter.StackContext;
+
+public abstract class If extends InstructionHandler
+{
+	@Override
+	public final void execute(Frame frame, InstructionContext ctx)
+	{
+		Stack intStack = frame.getIntStack();
+		int iop = ctx.getScriptInstruction().getIop();
+
+		StackContext sctx1 = intStack.pop();
+		StackContext sctx2 = intStack.pop();
+
+		ctx.popsInt(sctx1, sctx2);
+
+		Frame dup = frame.dup();
+		dup.jump(iop);
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/If_ICmpEQ.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+public class If_ICmpEQ extends If
+{
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/If_ICmpGE.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+public class If_ICmpGE extends If
+{
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/If_ICmpGT.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+public class If_ICmpGT extends If
+{
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/If_ICmpLE.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+public class If_ICmpLE extends If
+{
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/If_ICmpLT.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+public class If_ICmpLT extends If
+{
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/If_ICmpNE.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+public class If_ICmpNE extends If
+{
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/Jump.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+import net.runelite.cache.script.interpreter.Frame;
+import net.runelite.cache.script.interpreter.InstructionContext;
+import net.runelite.cache.script.interpreter.InstructionHandler;
+
+public class Jump extends InstructionHandler
+{
+	@Override
+	public void execute(Frame frame, InstructionContext ctx)
+	{
+		int iop = ctx.getScriptInstruction().getIop();
+		frame.jump(iop);
+	}
+
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/LoadInt.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+import net.runelite.cache.script.interpreter.Frame;
+import net.runelite.cache.script.interpreter.InstructionContext;
+import net.runelite.cache.script.interpreter.InstructionHandler;
+import net.runelite.cache.script.interpreter.Stack;
+import net.runelite.cache.script.interpreter.StackContext;
+
+public class LoadInt extends InstructionHandler
+{
+	@Override
+	public void execute(Frame frame, InstructionContext ctx)
+	{
+		Stack intStack = frame.getIntStack();
+		int iop = ctx.getScriptInstruction().getIop();
+
+		StackContext sctx = new StackContext(ctx, iop);
+		ctx.pushesInt(sctx);
+
+		intStack.push(sctx);
+	}
+}

cache/src/main/java/net/runelite/cache/script/interpreter/instructions/Return.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter.instructions;
+
+import net.runelite.cache.script.interpreter.Frame;
+import net.runelite.cache.script.interpreter.InstructionContext;
+import net.runelite.cache.script.interpreter.InstructionHandler;
+
+public class Return extends InstructionHandler
+{
+	@Override
+	public void execute(Frame frame, InstructionContext ctx)
+	{
+		frame.stop();
+	}
+
+}

cache/src/test/java/net/runelite/cache/script/interpreter/InterpreterTest.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2017, Adam <Adam@sigterm.info>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.runelite.cache.script.interpreter;
+
+import java.io.IOException;
+import java.io.InputStream;
+import net.runelite.cache.definitions.ScriptDefinition;
+import net.runelite.cache.script.assembler.Assembler;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class InterpreterTest
+{
+	@Test
+	public void testRun() throws IOException
+	{
+		InputStream in = InterpreterTest.class.getResourceAsStream("397.rs2asm");
+		Assert.assertNotNull(in);
+
+		Assembler assembler = new Assembler();
+		ScriptDefinition script = assembler.assemble(in);
+
+		Interpreter interpreter = new Interpreter();
+		interpreter.run(script);
+	}
+
+}

cache/src/test/resources/net/runelite/cache/script/interpreter/397.rs2asm

@@ -0,0 +1,50 @@
+   033                   
+   load_int               1
+   if_icmpne              LABEL4
+   jump                   LABEL5
+LABEL4:
+   return                
+LABEL5:
+   load_int               2871
+   load_int               1
+   load_int               0
+   3200                  
+   033                    1
+   load_int               1
+   if_icmpeq              LABEL13
+   jump                   LABEL20
+LABEL13:
+   025                    3985
+   033                    2
+   iadd                  
+   load_int               4
+   modulo                
+   027                    3985
+   jump                   LABEL41
+LABEL20:
+   033                    1
+   load_int               2
+   if_icmpeq              LABEL24
+   jump                   LABEL31
+LABEL24:
+   025                    3986
+   033                    2
+   iadd                  
+   load_int               4
+   modulo                
+   027                    3986
+   jump                   LABEL41
+LABEL31:
+   033                    1
+   load_int               3
+   if_icmpeq              LABEL35
+   jump                   LABEL41
+LABEL35:
+   025                    3987
+   033                    2
+   iadd                  
+   load_int               4
+   modulo                
+   027                    3987
+LABEL41:
+   return