ilo-vm/source/ilo.kt

// -------------------------------------------------------------
// ilo.kt, (c) charles childers
//
// build:
//
//   kotlinc ilo.kt -include-runtime -d ilo.jar
//
// run:
//
//   kotlin ilo.jar
// -------------------------------------------------------------

import java.io.File

var blocks = IntArray(1024*1024*4)
var input = ""
var ip = 0
var m = IntArray(65536)
var d = Stack()
var a = Stack()

fun ino() {}
fun ili() { ip++; d.push(m[ip]) }
fun idu() { d.push(d.tos()) }
fun idr() { d.pop() }
fun isw() { var x = d.pop(); var y = d.pop(); d.push(x); d.push(y) }
fun ipu() { a.push(d.pop()) }
fun ipo() { d.push(a.pop()) }
fun iju() { ip = d.pop() - 1 }
fun ica() { a.push(ip); iju() }
fun icc() { val t = d.pop(); if (d.pop() != 0) { a.push(ip); ip = t - 1 } }
fun icj() { val t = d.pop(); if (d.pop() != 0) { ip = t - 1 } }
fun ire() { ip = a.pop() }
fun ieq() { val x = d.pop(); val y = d.pop(); if (y == x) { d.push(-1) } else { d.push(0) } }
fun ine() { val x = d.pop(); val y = d.pop(); if (y != x) { d.push(-1) } else { d.push(0) } }
fun ilt() { val x = d.pop(); val y = d.pop(); if (y < x) { d.push(-1) } else { d.push(0) } }
fun igt() { val x = d.pop(); val y = d.pop(); if (y > x) { d.push(-1) } else { d.push(0) } }
fun ife() { val t = d.pop(); d.push(m[t]) }
fun ist() { val t = d.pop(); m[t] = d.pop() }
fun iad() { val x = d.pop(); val y = d.pop(); d.push(y + x) }
fun isu() { val x = d.pop(); val y = d.pop(); d.push(y - x) }
fun imu() { val x = d.pop(); val y = d.pop(); d.push(y * x) }
fun idi() { val x = d.pop(); val y = d.pop(); d.push(y % x); d.push(y / x) }
fun ian() { val x = d.pop(); val y = d.pop(); d.push(y and x) }
fun ior() { val x = d.pop(); val y = d.pop(); d.push(y or x) }
fun ixo() { val x = d.pop(); val y = d.pop(); d.push(y xor x) }
fun isl() { val x = d.pop(); val y = d.pop(); d.push(y shl x) }
fun isr() { val x = d.pop(); val y = d.pop(); d.push(y shr x) }
fun icp() {
  var l = d.pop()
  var t = d.pop()
  var s = d.pop()
  d.push(-1)
  while (l > 0) {
    if (m[t] != m[s]) { d.pop(); d.push(0) }
    t++; s++; l--
  }
}
fun icy() {
  var l = d.pop()
  var t = d.pop()
  var s = d.pop()
  while (l > 0) {
    m[t] = m[s]
    t++; s++; l--
  }
}
fun iio() {
  when (d.pop()) {
    0 -> io_co()
    1 -> io_ci()
    2 -> io_rb()
    3 -> io_wb()
    4 -> io_si()
    5 -> io_pc()
    6 -> io_of()
    7 -> io_sd()
  }
}

fun io_co() { print(d.pop().toChar()) }
fun io_ci() {
  if (input.length > 0) {
    val c = input.first()
    val v = c.code
    d.push(v)
    input = input.drop(1)
  } else {
    d.push(32)
  }
}
fun io_rb() { read_block() }
fun io_wb() { write_block() }
fun io_si() { }
fun io_pc() { boot(); ip = -1 }
fun io_of() { ip = 65536 }
fun io_sd() { d.push(d.depth()); d.push(a.depth()) }

// -------------------------------------------------------------
// -------------------------------------------------------------

fun load_blocks() {
  val bs = File("./ilo.blocks")
  val bytes:ByteArray = bs.readBytes()
  var i = 0
  var o = 0
  while (i < (1024*1024)) {
    val x = (bytes[o++].toInt() and 0xff shl 24) or
            (bytes[o++].toInt() and 0xff shl 16) or
            (bytes[o++].toInt() and 0xff shl 8) or
            (bytes[o++].toInt() and 0xff)
    blocks[i] = fix(x.toLong())
    i++
  }
}

fun read_block() {
  load_blocks()
  val buffer = d.pop()
  val block = d.pop()
  var i = 0
  while (i < 1024) {
    m[buffer + i] = blocks[(block * 1024) + i]
    i++
  }
}

fun write_block() {
  val buffer = d.pop()
  val block = d.pop()

  // update `blocks` cache
  var i = 0
  while (i < 1024) {
    blocks[(block * 1024) + i] = m[buffer + i]
    i++
  }

  // write `blocks` cache back to disk
  val bs = File("./ilo.blocks")
  var dump: ByteArray = ByteArray(1024*1024*4)

  i = 0
  var o = 0
  while (i < (1024*1024)) {
    val cell = fix(blocks[i].toLong())
    dump[o++] = ((cell shr 24) and 0xFF).toByte()
    dump[o++] = ((cell shr 16) and 0xFF).toByte()
    dump[o++] = ((cell shr 8) and 0xFF).toByte()
    dump[o++] = (cell and 0xFF).toByte()
    i++
  }
  bs.writeBytes(dump)
}

fun process_instruction(op: Int) {
  when (op) {
     0 -> ino()
     1 -> ili()
     2 -> idu()
     3 -> idr()
     4 -> isw()
     5 -> ipu()
     6 -> ipo()
     7 -> iju()
     8 -> ica()
     9 -> icc()
    10 -> icj()
    11 -> ire()
    12 -> ieq()
    13 -> ine()
    14 -> ilt()
    15 -> igt()
    16 -> ife()
    17 -> ist()
    18 -> iad()
    19 -> isu()
    20 -> imu()
    21 -> idi()
    22 -> ian()
    23 -> ior()
    24 -> ixo()
    25 -> isl()
    26 -> isr()
    27 -> icp()
    28 -> icy()
    29 -> iio()
    else -> {
      println("Invalid instruction!")
      print("IP:")
      print(ip)
      print(" OC:")
      println(op)
    }
  }
}

fun process() {
  while (input.length > 0 && ip < 65536) {
    val cur = ip
    process_instruction(m[cur] and 0xFF)
    process_instruction((m[cur] shr 8) and 0xFF)
    process_instruction((m[cur] shr 16) and 0xFF)
    process_instruction((m[cur] shr 24) and 0xFF)
    ip++
  }
}

fun boot() {
  load_image()
  load_blocks()
  ip = 0
  d.empty()
  a.empty()
  input = " "
  process()
}

fun load_image() {
  val bs = File("./ilo.rom")
  val bytes:ByteArray = bs.readBytes()
  var i = 0
  var o = 0
  while (i < 65536) {
    val x = (bytes[o++].toInt() and 0xff shl 24) or
            (bytes[o++].toInt() and 0xff shl 16) or
            (bytes[o++].toInt() and 0xff shl 8) or
            (bytes[o++].toInt() and 0xff)
    m[i] = fix(x.toLong())
    i++
  }
}

// The JVM is a big endian system. ilo stores data & rom in
// little endian. This routine converts the data between these
// when necessary.

fun fix(v: Long): Int {
  return (((v and 0x000000FF) shl 24) or
          ((v and 0x0000FF00) shl 8) or
          ((v and 0x00FF0000) shr 8) or
          ((v and 0xFF000000) shr 24)).toInt()
}

fun main(args: Array<String>) {
  boot()
  while (ip < 65536) {
    input = readln()
    input = " " + input + " \n"
    process()
  }
}


class Stack {
  var sp = 0
  var data = IntArray(256)

  fun push(v: Int) {
    sp++
    data[sp] = v
  }

  fun pop(): Int {
    sp--
    return data[sp + 1]
  }

  fun tos(): Int {
    return data[sp]
  }

  fun empty() {
    sp = 0
  }

  fun depth(): Int {
    return sp
  }
}