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From: Andi Kleen <ak@muc.de>
Subject: Re: Hotspot. Dynamic compilers "better" than static one?
Date: 1998/05/30
Message-ID: <m3d8cvfqbk.fsf@fred.muc.de>#1/1
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Organization: [posted via] Leibniz-Rechenzentrum, Muenchen (Germany)
Newsgroups: comp.lang.java.programmer,comp.lang.ada
Date: 1998-05-30T00:00:00+00:00
List-Id: <comp.lang.ada>


Roedy Green <roedy@oberon.ark.com> writes:

> Over a decade ago I spent months writing screaming fast code for the
> nucleus of a 32-bit Forth compiler that hand optimised every jump this way.
> The secondary advantage is that the most commonly used code is more likely
> to be pre-fetched or in cache.  A static optimiser can't do this, since it
> has no knowledge of which branch is the more likely.

Many modern compilers support profiling feedback. This means you compile
the program, run it to generate the profiling option and compile the
program again with feeding the profiling data into the compiler.

Dynamic compiling has the potential advantage that the code is tuned to
the particular usage pattern of the enduser, but I think for most programs
that does not matter much.

-Andi