Re: C++ to JVM compiler

From:

ram@zedat.fu-berlin.de (Stefan Ram)

Newsgroups:

comp.lang.c++,comp.lang.java.programmer

Date:

25 Apr 2008 22:14:44 GMT

Message-ID:

<switch-20080426001241@ram.dialup.fu-berlin.de>

Steve Wampler <swampler@noao.edu> writes:

I don't think I'd call it a limitation of the JVM, but of
automatic language translations in general. It can be very
hard to perform such a split while preserving the original
semantics and keeping the efficiency close to what was there
originally. Remember that you'd like such a process to work
correctly on the pathological cases as well as the simple ones.

  Scheme can be compiled to C or C++ using ?trampolining?.

  This will create one big function from the whole Scheme
  program, like

while( running )
{ switch( programm_counter )
  { case 0: /* compiler output for a scheme closure */ break;
    case 1: /* compiler output another scheme closure */ break;
    case 2: /* and so on */ break; ... }}

  Since the whole Scheme program is being compiled to one
  large switch, this switch might be larger than 64 K.

  Because (possibly small) closures are activated often,
  one does not want to have a call overhead for each closure
  activation.