Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!bu-cs!purdue!decwrl!sun!pitstop!sundc!seismo!uunet!mcvax!unido!uklirb!kirchner
From: kirchner@uklirb.UUCP (Reinhard Kirchner)
Newsgroups: comp.arch
Subject: Re: "interprocedural analysis useless for code optmization"
Message-ID: <2982@uklirb.UUCP>
Date: 19 Oct 88 14:28:57 GMT
References: <371@babbage.acc.virginia.edu>
Organization: University of Kaiserslautern, W-Germany
Lines: 19

From article <371@babbage.acc.virginia.edu>, by mac3n@babbage.acc.virginia.edu (Alex Colvin):
> 
> Pascal seems to have been designed to obviate the need for aliasing
> analysis.  It looks like it was successful.
> 
Also Pascal has some difficult to detect aliases. Among them are:

- VAR-Parameters and global variables
- VAR-Parameters and heap objects
- WITH-accessed parts of structures and direct accessed ones
- VAR-ARRAYs and VAR-Scalars

The VAR-Parameters are the main problem, because many objects which are
accessible as VAR-Parameter may also be accessed directly. So each access
to a VAR kills globals held in Registers and vice versa. I had lots of trouble
with these things when writing the codegenerator for Pascal-SC ( the one
which lets You prove that a CRAY is a way to compute wrong numbers VERY FAST-:)

R. Kirchner