From:	"A. Sinan Unur" <asu1 AT cornell DOT edu>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: How is switch implemented?
Date:	Wed, 02 Apr 1997 14:15:22 -0500
Organization:	Cornell University
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To:	djgpp AT delorie DOT com
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Jeff Standish wrote:
> I'm assuming that most intelligent compilers would try to use an jump
> table, but I don't know for certain, and I'm not in the mood to compile,
> disassemble, and try to read the machine code.  Besides, just because
> this might happen for a trivial test program doesn't mean it will also
> work for 40+ cases spread out over several hundred lines of code (which
> is the minimum of what I expect to write).

in the case of djgpp, you can specify a command line option that will
give you the assembly source files ( i think it was -S but i am at
school and cannot check now) however, just go to the info docs and look
at the section on invoking gcc.
> 
> And I'm asking this in a more general sense, since in addition to DJGPP > I also use Visual C++ 

> Does anyone know enough about the internals of compilers these days to
> answer this one?

in the case of djgpp, you can compile your actual code and take a look
at the assembly source rather than pure hex. i really do not know much
about the internals of the compilers but i saw it mentioned somewhere
that larger switch statements are more likely to be implemented using
jump tables.

-- sinan

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