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Mail Archives: djgpp/1994/10/14/08:52:47

From: Nigel Stephens <nigel AT algor DOT co DOT uk>
Date: Fri, 14 Oct 94 12:50:38 +0100
To: Francesc Guasch-Ortiz <frankie AT si DOT upc DOT es>
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: short data types
References: <150*/S=frankie/OU=si/O=upc/PRMD=iris/ADMD=mensatex/C=es/@MHS>

Francesc Guasch-Ortiz (frankie AT si DOT upc DOT es) writes:
 > that would explain why a program i made takes 30 seconds compiled under DJGPP
 > and 20 with other compiler that doesn't use protected mode. In that program
 > I make lots of calculations with BYTES. You mean if I replace every where i
 > put UNSIGNED CHAR for UNSIGNED INT i will get a better perfomance ?

This discussion does not apply to char (byte) operations, since they
do not require a special prefix opcode.  Byte operations *should*
execute as fast as 32-bit operations (in djgpp code); it is only
16-bit (i.e. short) operations that are slower.

Nigel
 _________________________________________________________________________
 Nigel Stephens, Algorithmics Ltd, 3 Drayton Park, London, N5 1NU, England
 phone: +44 171 700 3301   fax: +44 171 700 3400  email: nigel AT algor DOT co DOT uk

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