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Date: -- (:)
From: Xavier Leroy <xavier.leroy@i...>
Subject: Re: [Caml-list] Timing Ocaml
> I see... But there is another solution: use C switch() operator in interp
> main loop that is translated to jump table by MSVC optimizer (don't know if
> gcc is capable to do this).

Dmitry, don't be naive: of course the bytecode interpretor loop uses
switch() if computed gotos are not available, and of course any C
compiler translates this switch() to a jump table.  But the jumptable
is still significantly slower than the computed goto trick, since it
involves one extra compare-and-branch and one extra memory load.

This discussion ("efficient bytecode interpreters") is getting
off-topic for caml-list, so please let's stop here.  If you're still
curious, the best way to understand the issues at hand is to stare at
the assembly code generated for interp.c :-)

- Xavier Leroy
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