remove rewriteIndex, no longer needed

compiler/src/l3/CPSValueRepresenter.scala

@@ -151,12 +151,14 @@ object CPSValueRepresenter extends (H.Tree => L.Tree) {
       case L3.BlockSet => 
         val block = rewrite(x)
         val value = rewrite(z)
-        rewriteIndex(y) {idx => L.LetP(n, CPS.BlockSet, Seq(block, idx, value), apply(body))}
+        tempLetP(CPS.ShiftRight, Seq(Left(y), Right(L.AtomL(1)))){idx => 
+          L.LetP(n, CPS.BlockSet, Seq(block, idx, value), apply(body))
+        }
       case L3.BlockGet => 
         val block = rewrite(x)
-        rewriteIndex(y){idx => L.LetP(n, CPS.BlockGet, Seq(block, idx), apply(body))}
-
-
+        tempLetP(CPS.ShiftRight, Seq(Left(y), Right(L.AtomL(1)))){
+          idx => L.LetP(n, CPS.BlockGet, Seq(block, idx), apply(body))
+        }
       case L3.ByteRead =>
         tempLetP(CPS.ByteRead, Seq()){ t1 => 
           tempLetP(CPS.ShiftLeft, Seq(Right(t1), lAtomOne)) { t2 =>
@@ -206,11 +208,4 @@ object CPSValueRepresenter extends (H.Tree => L.Tree) {
         L.AtomL(0x0a) // 01010
     case H.AtomL(UnitLit) => L.AtomL(2)
   }
-
-  private def rewriteIndex(idx: H.Atom)(cont: L.Atom => L.LetP): L.LetP = idx match {
-    case H.AtomN(n) => 
-      tempLetP(CPS.ShiftRight, Seq(Left(idx), Right(L.AtomL(1))))(cont)
-    case H.AtomL(IntLit(i)) => cont(L.AtomL(i.toInt))
-    case _ => throw new Exception(f"Cannot rewrite atom {idx} which is not Name or Int Literal")
-  }
 }