Re: FRAC tool?

[Robert Dewar <robert_dewar@my-deja.com>]

In article <2oRa3.14$Lc3.1167@typhoon.nyu.edu>,
 kenner@lab.ultra.nyu.edu (Richard Kenner) wrote:

> Not completely, especially in the presence of optimization.
>
> Consider:
>
> 	A := A * 4;
> 	A := A + B;
>
> On the Alpha, that can be done in one instruction, so only one
of those
> lines can be considered to generate code.


You misunderstand my criterion. In this case I would still say
that both statements generate code. The fact that the single
amazing Alpha instruction will take care of both statements
is interesting but irrelevant.

The issue is whether the given statements generate code. In
this case clearly both statements generate code. The fact that
the one instruction of the code takes care of both statements
does not change this fact.

If you think of Ada as defined by a virtual operational machine,
the issue is whether this virtual operational machine would have
code generated, assuming an appropriate realistic abstraction
level for the machine.

Sure this is vague, but could be made quite precise if someone
desired to do so.

I still see a quite clear intuitive distinction between the
above two statements, and a statement that says

 >begin

:-)




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