Build tape optimization

[arakov]

• extra temporal variables

• boxing an array, assigning to the local variable - get rid of double assigning

• dirty_ptr := dirty_ptr + int

• copy a sub array to another array - starting

• copy a sub array to another array

• tuple / array unboxing

• optimization single dispatching

• String.prop:Length[1]

• optimization sealed dispatching

• optimization xstore sp:0, 0 and xstore sp:1, 0 - should be replaced with xor operation

• comparing Handle with WindowHandle should be native

• optimize Amicable pairs

• getting / setting a prop field - should be done directly if it is trivial getter / setter

• unused allocated variable should be removed to spare stack

• BuildKey::CopyingAccField, 0

• get rid of extra assigning here:

  class A
  {
      object field;
  
      object Value
         = field;
  
      constructor(value)
      {
         field := value;
      }
  }
  
  public program()
  {
     A a := new A(2);
  
     var val := *a;
  }
  

The output is:

>@function program.function:#invoke
       xflush       sp:0
       open           :4, :0
       store        fp:1
       xstore       sp:0, intconst:2
       set       class:sandbox'$private'A
       mov        mssg:function:#constructor[1]
       call       mssg:function:#constructor[1], class:sandbox'$private'A#class
       store        fp:3  // an extra save?
       store        fp:2   
       store        sp:0
       mov        mssg:prop:Value[1]
       call         vt:0
       store        fp:3
       peek         fp:1
Lab00:     nop
       close          :0
       quit           
@end