--- a/scala/compile.scala Sat Jun 15 09:11:11 2013 -0400
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,326 +0,0 @@
-// A parser and evaluator for teh while language
-//
-import matcher._
-import parser._
-
-// some regular expressions
-val SYM = RANGE("ABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyz_")
-val DIGIT = RANGE("0123456789")
-val ID = SEQ(SYM, STAR(ALT(SYM, DIGIT)))
-val NUM = PLUS(DIGIT)
-val KEYWORD = ALTS("skip", "while", "do", "if", "then", "else", "true", "false", "write")
-val SEMI: Rexp = ";"
-val OP: Rexp = ALTS(":=", "=", "-", "+", "*", "!=", "<", ">")
-val WHITESPACE = PLUS(RANGE(" \n"))
-val RPAREN: Rexp = ")"
-val LPAREN: Rexp = "("
-val BEGIN: Rexp = "{"
-val END: Rexp = "}"
-val COMMENT = SEQS("/*", NOT(SEQS(STAR(ALLC), "*/", STAR(ALLC))), "*/")
-
-// tokens for classifying the strings that have been recognised
-abstract class Token
-case object T_WHITESPACE extends Token
-case object T_COMMENT extends Token
-case object T_SEMI extends Token
-case object T_LPAREN extends Token
-case object T_RPAREN extends Token
-case object T_BEGIN extends Token
-case object T_END extends Token
-case class T_ID(s: String) extends Token
-case class T_OP(s: String) extends Token
-case class T_NUM(s: String) extends Token
-case class T_KWD(s: String) extends Token
-
-val lexing_rules: List[(Rexp, List[Char] => Token)] =
- List((KEYWORD, (s) => T_KWD(s.mkString)),
- (ID, (s) => T_ID(s.mkString)),
- (OP, (s) => T_OP(s.mkString)),
- (NUM, (s) => T_NUM(s.mkString)),
- (SEMI, (s) => T_SEMI),
- (LPAREN, (s) => T_LPAREN),
- (RPAREN, (s) => T_RPAREN),
- (BEGIN, (s) => T_BEGIN),
- (END, (s) => T_END),
- (WHITESPACE, (s) => T_WHITESPACE),
- (COMMENT, (s) => T_COMMENT))
-
-// the tokenizer
-val Tok = Tokenizer(lexing_rules, List(T_WHITESPACE, T_COMMENT))
-
-// the abstract syntax trees
-abstract class Stmt
-abstract class AExp
-abstract class BExp
-type Block = List[Stmt]
-case object Skip extends Stmt
-case class If(a: BExp, bl1: Block, bl2: Block) extends Stmt
-case class While(b: BExp, bl: Block) extends Stmt
-case class Assign(s: String, a: AExp) extends Stmt
-case class Write(s: String) extends Stmt
-
-case class Var(s: String) extends AExp
-case class Num(i: Int) extends AExp
-case class Aop(o: String, a1: AExp, a2: AExp) extends AExp
-
-case object True extends BExp
-case object False 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] {
- def parse(ts: List[Token]) = ts match {
- case t::ts if (t == tok) => Set((t, ts))
- case _ => Set ()
- }
-}
-implicit def token2tparser(t: Token) = TokParser(t)
-
-case object NumParser extends Parser[List[Token], Int] {
- def parse(ts: List[Token]) = ts match {
- case T_NUM(s)::ts => Set((s.toInt, ts))
- case _ => Set ()
- }
-}
-
-case object IdParser extends Parser[List[Token], String] {
- def parse(ts: List[Token]) = ts match {
- case T_ID(s)::ts => Set((s, ts))
- case _ => Set ()
- }
-}
-
-
-// arithmetic expressions
-lazy val AExp: Parser[List[Token], AExp] =
- (T ~ T_OP("+") ~ AExp) ==> { case ((x, y), z) => Aop("+", x, z): AExp } ||
- (T ~ T_OP("-") ~ AExp) ==> { case ((x, y), z) => Aop("-", x, z): AExp } || T
-lazy val T: Parser[List[Token], AExp] =
- (F ~ T_OP("*") ~ T) ==> { case ((x, y), z) => Aop("*", x, z): AExp } || F
-lazy val F: Parser[List[Token], AExp] =
- (T_LPAREN ~> AExp <~ T_RPAREN) ||
- IdParser ==> Var ||
- NumParser ==> Num
-
-// boolean expressions
-lazy val BExp: Parser[List[Token], BExp] =
- (T_KWD("true") ==> ((_) => True: BExp)) ||
- (T_KWD("false") ==> ((_) => False: BExp)) ||
- (T_LPAREN ~> BExp <~ T_RPAREN) ||
- (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)) ||
- (IdParser ~ T_OP(":=") ~ AExp) ==> { case ((x, y), z) => Assign(x, z): Stmt } ||
- (T_KWD("if") ~ BExp ~ T_KWD("then") ~ Block ~ T_KWD("else") ~ Block) ==>
- { case (((((x,y),z),u),v),w) => If(y, u, w): Stmt } ||
- (T_KWD("while") ~ BExp ~ T_KWD("do") ~ Block) ==> { case (((x, y), z), w) => While(y, w) } ||
- (T_KWD("write") ~ IdParser) ==> { case (x, y) => Write(y) }
-
-lazy val Stmts: Parser[List[Token], Block] =
- (Stmt ~ T_SEMI ~ Stmts) ==> { case ((x, y), z) => x :: z : Block } ||
- (Stmt ==> ((s) => List(s) : Block))
-
-lazy val Block: Parser[List[Token], Block] =
- (T_BEGIN ~> Stmts <~ T_END) ||
- (Stmt ==> ((s) => List(s)))
-
-// compiler
-val beginning = """
-.class public XXX.XXX
-.super java/lang/Object
-
-.method public <init>()V
- aload_0
- invokenonvirtual java/lang/Object/<init>()V
- return
-.end method
-
-.method public static write(I)V
- .limit locals 5
- .limit stack 5
- iload 0
- getstatic java/lang/System/out Ljava/io/PrintStream;
- swap
- invokevirtual java/io/PrintStream/println(I)V
- return
-.end method
-
-
-.method public static main([Ljava/lang/String;)V
- .limit locals 200
- .limit stack 200
-
-"""
-
-val ending = """
-
- return
-
-.end method
-"""
-
-// for generating new labels
-var counter = -1
-
-def Fresh(x: String) = {
- counter += 1
- x ++ "_" ++ counter.toString()
-}
-
-type Env = Map[String, String]
-type Instrs = List[String]
-
-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")
- case Aop("-", a1, a2) => compile_aexp(a1, env) ++ compile_aexp(a2, env) ++ List("isub\n")
- case Aop("*", a1, a2) => compile_aexp(a1, env) ++ compile_aexp(a2, env) ++ List("imul\n")
-}
-
-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 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) : (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))
- }
- case If(b, bl1, bl2) => {
- val if_else = Fresh("If_else")
- val if_end = Fresh("If_end")
- val (instrs1, env1) = compile_bl(bl1, env)
- val (instrs2, env2) = compile_bl(bl2, env1)
- (compile_bexp(b, env, if_else) ++
- instrs1 ++
- List("goto " + if_end + "\n") ++
- List("\n" + if_else + ":\n\n") ++
- instrs2 ++
- List("\n" + if_end + ":\n\n"), env2)
- }
- case While(b, bl) => {
- val loop_begin = Fresh("Loop_begin")
- val loop_end = Fresh("Loop_end")
- val (instrs1, env1) = compile_bl(bl, env)
- (List("\n" + loop_begin + ":\n\n") ++
- compile_bexp(b, env, loop_end) ++
- instrs1 ++
- List("goto " + loop_begin + "\n") ++
- List("\n" + loop_end + ":\n\n"), env1)
- }
- case Write(x) =>
- (List("iload " + env(x) + "\n" + "invokestatic XXX/XXX/write(I)V\n"), env)
-}
-
-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)
- val (instrs2, env2) = compile_bl(bl, env1)
- (instrs1 ++ instrs2, env2)
- }
-}
-
-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).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
-
-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
-
-
-
-
-
-