Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!cmcl2!kramden.acf.nyu.edu!brnstnd
From: brnstnd@kramden.acf.nyu.edu (Dan Bernstein)
Newsgroups: comp.lang.misc
Subject: Re: Answers, Chapter 1: TeX
Message-ID: <12614:Nov801:02:4990@kramden.acf.nyu.edu>
Date: 8 Nov 90 01:02:49 GMT
References: <12004:Nov723:40:2890@kramden.acf.nyu.edu> <5241@lanl.gov>
Organization: IR
Lines: 27

In article <5241@lanl.gov> jlg@lanl.gov (Jim Giles) writes:
> The number of different _possible_ partitions in your scheme varies
> as 2^N where N is the number of procedure arguments.

No, it does not. That's the third incorrect formula you've posted for
the same quantity.

Even if you were right, no sane compiler would generate *every* possible
partition. It would just generate up to the space-time tradeoff decided
by the implementor. If you are correct that most code doesn't have
aliasing, then the right spot to chop off is at TWO partitions. One says
that all arguments of this type are aliased, one says that none are.

> This ignores the
> possible aliasing of globals which multiplies in another big factor.

I have not been ignoring globals; as I indicate in the article you're
studying, *all* possibly aliased pointers must be considered together.

> Well, you have an exponential naming problem (at least), which is more
> than a few bits.

Again, you are dreaming. Say the compiler gives up at 20 copies of the
same code (which in practice gives hellishly good coverage). How many
bits does it take to encode an integer between 1 and 20.

---Dan