Re: Converting the gcc backend to a library?

[Alexandre Oliva <oliva at lsd dot ic dot unicamp dot br>]

On Jan 10, 2000, kenner@vlsi1.ultra.nyu.edu (Richard Kenner) wrote:

>     Think of a Web server running multiple CGI scripts written in Perl,
>     Python, Guile, whatever, plus Java servlets.  If all of these
>     environments could be linked with the same JIT compiler shared
>     library, wouldn't it be just great?

> Perhaps, but you're talking about saving perhaps 1.2 MB per process and
> these are likely ones that will have large dataspaces anyway, so the
> actual savings even on such a server will likely turn out negligable
> if you do the calculations.

Even if this is the case.  I've been advocating creating a library out
of the back end not for memory or disk-space savings, but to ease the
creation of dynamic compilation environments.  I know well that GCC is
not the only piece of software that must be changed to allow this: we
also need a dynamic assembler, that, instead of reading from a file
and generating assembly to a file, would assemble into memory.  I hope
this is not too hard to do with some hacking of binutils, by arranging
that some additional parts of as and ld are moved into a library.

Hopefully, in a few months/years, dynamic compilation with the GNU
toolchain (libchain?) would be achievable by simply creating some
trees and asking the back-end to generate native code.

OTOH, I understand that several trade-offs of GCC don't make it
suitable for such a dynamic compilation environment.  But I doubt it
would be worth to duplicate all the effort that has already been put
into it.  Moreover, adapting GCC to such an environment would
certainly be a lot of fun! :-)

-- 
Alexandre Oliva http://www.ic.unicamp.br/~oliva IC-Unicamp, Bra[sz]il
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