From 3988f16ad4f66214683b01648edd20855ccf30c6 Mon Sep 17 00:00:00 2001
From: Gabriel Tofvesson <gabto095@student.liu.se>
Date: Fri, 5 Apr 2019 14:06:30 +0200
Subject: [PATCH] Add compiler implemented in Kotlin

---
 compiler.kt | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 92 insertions(+)
 create mode 100644 compiler.kt

diff --git a/compiler.kt b/compiler.kt
new file mode 100644
index 0000000..9c22795
--- /dev/null
+++ b/compiler.kt
@@ -0,0 +1,92 @@
+import java.io.*
+
+enum class OpCode(val opcode: Int, val useM: Boolean, val useADR: Boolean, val useReg: Boolean = true) {
+	LOAD(0, true, true),
+	STORE(1, true, true),
+	ADD(2, true, true),
+	SUB(3, true, true),
+	AND(4, true, true),
+	LSR(5, true, true),
+	BRA(6, false, true),
+	BNE(7, false, true),
+	CMP(8, true, false),
+	BEQ(9, false, true),
+	HALT(15, false, false, false)
+}
+
+enum class Mode(val id: Int) {
+	DIRECT(0), IMMEDIATE(1), INDIRECT(2), INDEXED(3)
+}
+
+interface Instruction {
+	fun getData(insns: Iterable<Instruction>): Short
+}
+
+class Label(val name: String): Instruction {
+	override fun getData(insns: Iterable<Instruction>) = 0.toShort()
+}
+
+class Immediate(val data: Short): Instruction {
+	override fun getData(insns: Iterable<Instruction>) = data
+}
+
+class Operation(val code: OpCode, val reg: Int, val m: Mode, val adr: AddressReference): Instruction {
+	constructor(val code: OpCode): this(code, 0, Mode.DIRECT, AddressReference(0))
+	
+	override fun getData(insns: Iterable<Instruction>): Short {
+		return code.opcode
+			.and(0b1111)
+			.shl(12)
+			.or(
+				if(code.useReg) reg.and(0b11).shl(10)
+				else 0
+			)
+			.or(
+				if(code.useM) m.id.and(0b11).shl(8)
+				else 0
+			)
+			.or(
+				if(code.useADR) adr.getAddress(insns).and(0b11111111)
+				else 0
+			)
+			.toShort()
+	}
+}
+
+class AddressReference(private val label: Label?, private val absolute: Int?) {
+	constructor(label: Label): this(label, null)
+	constructor(absolute: Int): this(null, absolute)
+
+	fun getAddress(insns: Iterable<Instruction>): Int {
+		if(absolute != null) return absolute
+		insns.forEachIndexed{ index, insn ->
+			if(insn == label)
+				return@getAddress index*2
+		}
+
+		throw RuntimeException("Label cannot be found in set of instructions!")
+	}
+}
+
+fun main(args: Array<String>){
+	// Ensure correct argument length 'n stuff
+	if(args.size != 1){
+		System.err.println("Invalid argument length!")
+		System.exit(-1)
+	}
+
+	val file = File(args[0])
+
+	// Make sure we have a valid file
+	if(!file.isFile){
+		System.err.println("Given file doesn't exist!")
+		System.exit(-2)
+	}
+
+	val insns = ArrayList<Instruction>()
+	insns.add(Operation(OpCode.LOAD, 0, Mode.DIRECT, AddressReference(1337)))
+	insns.add(Operation(OpCode.HALT))
+
+}
+
+