diff -r fd894e017e12 -r 191daa3ee29e compile.scala
--- a/compile.scala	Sat Nov 24 15:10:43 2012 +0000
+++ b/compile.scala	Mon Nov 26 01:11:55 2012 +0000
@@ -10,7 +10,7 @@
 val NUM = PLUS(DIGIT)
 val KEYWORD = ALTS("skip", "while", "do", "if", "then", "else", "true", "false", "write") 
 val SEMI: Rexp = ";"
-val OP: Rexp = ALTS(":=", "=", "-", "+", "*", "!", "<", ">")
+val OP: Rexp = ALTS(":=", "=", "-", "+", "*", "!=", "<", ">")
 val WHITESPACE = PLUS(RANGE(" \n"))
 val RPAREN: Rexp = ")"
 val LPAREN: Rexp = "("
@@ -65,7 +65,7 @@
 
 case object True extends BExp
 case object False extends BExp
-case class Bop(o: String, a1: AExp, a2: AExp) extends BExp
+case class Relop(o: String, a1: AExp, a2: AExp) extends BExp
 
 // atomic parsers
 case class TokParser(tok: Token) extends Parser[List[Token], Token] {
@@ -107,10 +107,10 @@
   (T_KWD("true") ==> ((_) => True: BExp)) || 
   (T_KWD("false") ==> ((_) => False: BExp)) ||
   (T_LPAREN ~> BExp <~ T_RPAREN) ||
-  (AExp ~ T_OP("=") ~ AExp) ==> { case ((x, y), z) => Bop("=", x, z): BExp } || 
-  (AExp ~ T_OP("!=") ~ AExp) ==> { case ((x, y), z) => Bop("!=", x, z): BExp } || 
-  (AExp ~ T_OP("<") ~ AExp) ==> { case ((x, y), z) => Bop("<", x, z): BExp } || 
-  (AExp ~ T_OP(">") ~ AExp) ==> { case ((x, y), z) => Bop("<", z, x): BExp } 
+  (AExp ~ T_OP("=") ~ AExp) ==> { case ((x, y), z) => Relop("=", x, z): BExp } || 
+  (AExp ~ T_OP("!=") ~ AExp) ==> { case ((x, y), z) => Relop("!=", x, z): BExp } || 
+  (AExp ~ T_OP("<") ~ AExp) ==> { case ((x, y), z) => Relop("<", x, z): BExp } || 
+  (AExp ~ T_OP(">") ~ AExp) ==> { case ((x, y), z) => Relop("<", z, x): BExp } 
 
 lazy val Stmt: Parser[List[Token], Stmt] =
   (T_KWD("skip") ==> ((_) => Skip: Stmt)) ||
@@ -128,9 +128,9 @@
   (T_BEGIN ~> Stmts <~ T_END) || 
   (Stmt ==> ((s) => List(s)))
 
-// interpreter
+// compiler
 val beginning = """
-.class public examples/HelloWorld
+.class public XXX.XXX
 .super java/lang/Object
 
 .method public <init>()V
@@ -172,8 +172,9 @@
 }
 
 type Env = Map[String, String]
+type Instrs = List[String]
 
-def compile_aexp(a: AExp, env : Env) : List[String] = a match {
+def compile_aexp(a: AExp, env : Env) : Instrs = a match {
   case Num(i) => List("ldc " + i.toString + "\n")
   case Var(s) => List("iload " + env(s) + "\n")
   case Aop("+", a1, a2) => compile_aexp(a1, env) ++ compile_aexp(a2, env) ++ List("iadd\n")
@@ -181,19 +182,24 @@
   case Aop("*", a1, a2) => compile_aexp(a1, env) ++ compile_aexp(a2, env) ++ List("imul\n")
 }
 
-def compile_bexp(b: BExp, env : Env, jmp: String) : List[String] = b match {
-  case Bop("=", a1, a2) => 
+def compile_bexp(b: BExp, env : Env, jmp: String) : Instrs = b match {
+  case True => Nil
+  case False => List("goto " + jmp + "\n")
+  case Relop("=", a1, a2) => 
     compile_aexp(a1, env) ++ compile_aexp(a2, env) ++ List("if_icmpne " + jmp + "\n")
-  case Bop("<", a1, a2) => 
+  case Relop("!=", a1, a2) => 
+    compile_aexp(a1, env) ++ compile_aexp(a2, env) ++ List("if_icmpeq " + jmp + "\n")
+  case Relop("<", a1, a2) => 
     compile_aexp(a1, env) ++ compile_aexp(a2, env) ++ List("if_icmpge " + jmp + "\n")
 }
 
 
-def compile_stmt(s: Stmt, env: Env) : (List[String], Env) = s match {
+def compile_stmt(s: Stmt, env: Env) : (Instrs, Env) = s match {
   case Skip => (Nil, env)
   case Assign(x, a) => {
     val index = if (env.isDefinedAt(x)) env(x) else env.keys.size.toString
-    (compile_aexp(a, env) ++ List("istore " + index + "\n"), env + (x -> index))
+    (compile_aexp(a, env) ++ 
+     List("istore " + index + "\n"), env + (x -> index))
   } 
   case If(b, bl1, bl2) => {
     val if_else = Fresh("If_else")
@@ -218,10 +224,10 @@
      List("\n" + loop_end + ":\n\n"), env1)
   }
   case Write(x) => 
-    (List("iload " + env(x) + "\n" + "invokestatic examples/HelloWorld/write(I)V\n"), env)
+    (List("iload " + env(x) + "\n" + "invokestatic XXX/XXX/write(I)V\n"), env)
 }
 
-def compile_bl(bl: Block, env: Env) : (List[String], Env) = bl match {
+def compile_bl(bl: Block, env: Env) : (Instrs, Env) = bl match {
   case Nil => (Nil, env)
   case s::bl => {
     val (instrs1, env1) = compile_stmt(s, env)
@@ -230,18 +236,88 @@
   }
 }
 
-def compile(name: String) : String = {
-  val tks = Tok.fromFile(name)
+def compile(input: String) : String = {
+  val class_name = input.split('.')(0)
+  val tks = Tok.fromFile(input)
   val ast = Stmts.parse_single(tks)
   val instructions = compile_bl(ast, Map.empty)._1
-  beginning ++ instructions.mkString ++ ending
+  (beginning ++ instructions.mkString ++ ending).replaceAllLiterally("XXX", class_name)
 }
 
 
+def compile_to(input: String, output: String) = {
+  val fw = new java.io.FileWriter(output) 
+  fw.write(compile(input)) 
+  fw.close()
+}
+
+//
+val tks = Tok.fromString("x := x + 1")
+val ast = Stmt.parse_single(tks)
+println(compile_stmt(ast, Map("x" -> "n"))._1.mkString)
+
+
+
 //examples
 
-println(compile("loops.while"))
-//println(compile("fib.while"))
+//compile_to("loops.while", "loops.j")
+//compile_to("fib.while", "fib.j")
+
+
+// testing cases for time measurements
+
+def time_needed[T](i: Int, code: => T) = {
+  val start = System.nanoTime()
+  for (j <- 1 to i) code
+  val end = System.nanoTime()
+  (end - start)/(i * 1.0e9)
+}
+
+// for testing
+import scala.sys.process._
+
+val test_prog = """
+start := XXX;
+x := start;
+y := start;
+z := start;
+while 0 < x do {
+ while 0 < y do {
+  while 0 < z do {
+    z := z - 1
+  };
+  z := start;
+  y := y - 1
+ };     
+ y := start;
+ x := x - 1
+};
+write x;
+write y;
+write z
+"""
+
+
+def compile_test(n: Int) : Unit = {
+  val class_name = "LOOP"
+  val tks = Tok.fromString(test_prog.replaceAllLiterally("XXX", n.toString))
+  val ast = Stmts.parse_single(tks)
+  val instructions = compile_bl(ast, Map.empty)._1
+  val assembly = (beginning ++ instructions.mkString ++ ending).replaceAllLiterally("XXX", class_name)
+  val fw = new java.io.FileWriter(class_name + ".j") 
+  fw.write(assembly) 
+  fw.close()
+  val test = ("java -jar jvm/jasmin-2.4/jasmin.jar " + class_name + ".j").!!
+  println(n + " " + time_needed(2, ("java " + class_name + "/" + class_name).!!))
+}
+
+List(1, 5000, 10000, 50000, 100000, 250000, 500000, 750000, 1000000).map(compile_test(_))
+
+
+
+// javabyte code assmbler
+//
+// java -jar jvm/jasmin-2.4/jasmin.jar loops.j
 
 
 
@@ -249,5 +325,3 @@
 
 
 
-
-