Aucbvax.6807
fa.info-vax
utzoo!decvax!ucbvax!info-vax
Mon Apr 19 19:03:38 1982
Vax compilers
>From GJC@MIT-MC Mon Apr 19 18:57:23 1982
[Beware, this note talks about both VMS and Unix, and assumes either
 background information or willingness to do a little research on the
 part of the reader.]

For some background on the technology used in the DEC language
implementations on the VAX see Wulf's "Design of an Optimizing
Compiler." For background on Unix compiler technology see the Aho & Ulman
"dragon book." As the Unix people talk about the Fortran optimization
issue in terms of "we are working on adding an optimization pass to
the compiler," well, it is enough to say that the background info
is useful in evaluating statements of this kind.

Other things to consider include operating system support for things
such as sharable (in the pure-page mapping sense) libraries of fortran
and other language routines. Since commonly used graphics and numerical
routines do tend to be large (featurefull), sharability of code
called through the procedure-call mechanism becomes an important
performance consideration. The Unix mechanism for sharability works
through communication via pipeline, not procedure-call, this an understandable
developement given the pdp-11 architecture. (I'm not lambasting the pipelines
other uses of course!). 

-gjc

p.s. Investigate the Eunice route.