# HG changeset patch
# User Christian Urban <urbanc@in.tum.de>
# Date 1543305237 0
# Node ID 060f33b5661d9f45b4bc923105dc2f9781e439ac
# Parent  7ec1bdb670ba0bab145bb8d7ced88a89180131ed
updated

diff -r 7ec1bdb670ba -r 060f33b5661d progs/compile_arr.scala
--- a/progs/compile_arr.scala	Tue Nov 27 01:15:54 2018 +0000
+++ b/progs/compile_arr.scala	Tue Nov 27 07:53:57 2018 +0000
@@ -1,5 +1,5 @@
 // A Small Compiler for the WHILE Language
-// (it does not use a parser and lexer)
+// (stub for including arrays)
 
 // the abstract syntax trees
 abstract class Stmt
@@ -12,8 +12,7 @@
 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 Read(s: String) extends Stmt
+case class Write(s: String) extends Stmt  // writes out a variable
 
 // arithmetic expressions
 case class Var(s: String) extends AExp
@@ -47,40 +46,6 @@
     return 
 .end method
 
-.method public static read()I 
-    .limit locals 10 
-    .limit stack 10
-
-    ldc 0 
-    istore 1  ; this will hold our final integer 
-Label1: 
-    getstatic java/lang/System/in Ljava/io/InputStream; 
-    invokevirtual java/io/InputStream/read()I 
-    istore 2 
-    iload 2 
-    ldc 10   ; the newline delimiter 
-    isub 
-    ifeq Label2 
-    iload 2 
-    ldc 32   ; the space delimiter 
-    isub 
-    ifeq Label2
-
-    iload 2 
-    ldc 48   ; we have our digit in ASCII, have to subtract it from 48 
-    isub 
-    ldc 10 
-    iload 1 
-    imul 
-    iadd 
-    istore 1 
-    goto Label1 
-Label2: 
-    ;when we come here we have our integer computed in local variable 1 
-    iload 1 
-    ireturn 
-.end method
-
 .method public static main([Ljava/lang/String;)V
    .limit locals 200
    .limit stack 200
@@ -171,12 +136,6 @@
   case Write(x) => 
     (List("iload " + env(x) + "\n" + 
            "invokestatic XXX/XXX/write(I)V\n"), env)
-  case Read(x) => {
-    val index = if (env.isDefinedAt(x)) env(x) else 
-                    env.keys.size.toString
-    (List("invokestatic XXX/XXX/read()I\n" + 
-          "istore " + index + "\n"), env + (x -> index))
-  }
 }
 
 // compilation of a block (i.e. list of instructions)
@@ -259,3 +218,15 @@
 compile_run(fib_test, "fib")
 
 
+
+val arr_test = 
+  List(Array("a", 10),
+       Array("b", 2),
+       AssignA("a", Num(0), Num(10)),
+       Assign("x", Ref("a", Num(0))),
+       Write("x"),
+       AssignA("b", Num(1), Num(5)),
+       Assign("x", Ref("b", Num(1))),
+       Write("x"))       
+
+//compile_run(arr_test, "a")
\ No newline at end of file