SIMPLE: A language-independent tree IR

[Alexandre Oliva]

On Jan  2, 2002, Diego Novillo <dnovillo@redhat.com> wrote:

>      1	 x = a OP b
>      2	*a = b OP c
>      3	 x = OP c
>      4	*a = x
>      5	*a = f(args)
>      6	*a = *c
>      7	*a = (cast)b
>      8	*a = &x
>      9	 x = y
>     10	 x = &y
>     11	 x = *c
>     12	 x = f(args)
>     13   x = (cast)b
>     14	 f(args)

To me, this doesn't look too different from RTL.  The only important
difference appears to be the fact that arguments to function calls are
explicitly listed.  I fail to see the advantage of such an IR over a
machine-independent RTL, as previously suggested by Jeff Law.  In
fact, I fail to see the advantage of using this as a tree
representation: with such basic statement and expression types, it
appears to me that you lose any benefit you might have from using
trees, and sticking to a machine-independent RTL would be just the
same.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
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