I might also add that since this sort of method achieves it's result through
observing "the program's behavior" and applying appropriate optimizations,
this method would appear to be attempting to replicate the observation and
optimization techniques (albeit low-level) of a human programmer. Or perhaps
to do better than a human. This would seem to fall into the domain of
Artificial Intelligence. I say, stop arguing and get on with the job. I
haven't seen anything else interesting on this forum lately.
From: Rick Rankin
Sent: Friday, August 10, 2001 7:11 PM
Subject: Re: Supercompiled Perl: HP's Dynamo Project
It's not like this kind of thing hasn't been done before:
"Dynamic optimization refers to the runtime optimization of a native program
paper describes the design and implementation of Dynamo, a prototype dynamic
optimizer that is
capable of optimizing a native program binary at runtime. Dynamo is a
realistic implementation, not
a simulation, that is written entirely in user-level software, and runs on a
PA-RISC machine under
the HPUX operating system.
Dynamo does not depend on any special programming language, compiler,
operating system or
hardware support. The program binary is not instrumented and is left
untouched during Dynamo's
operation. Dynamo observes the program's behavior through interpretation to
dynamically select hot
instruction traces from the running program. The hot traces are optimized
optimization techniques and emitted into a software code cache. Subsequent
instances of these traces
cause the cached version to be executed, resulting in a performance boost.
Contrary to intuition, we demonstrate that it is possible to use a piece of
software to improve
the performance of a native, statically optimized program binary, while it
is executing. Dynamo not
only speeds up real application programs, its performance improvement is
often quite significant.
For example, the performance of many +O2 optimized SPECint95 binaries
running under Dynamo is
comparable to the performance of their +O4 optimized version running without
Transparent Dynamic Optimization;Vasanth Bala, Evelyn Duesterwald, Sanjeev
Banerjia;HP Laboratories Cambridge;June, 1999
From: John Porter
Sent: Friday, August 10, 2001 3:54 PM
Subject: Re: Modern Programming Language Concepts
Nathan Torkington wrote:
I'd much rather get no signal than all noise.
Couldna said it better myself.