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Mail Archives: djgpp/1994/01/10/11:18:22

Date: Mon, 10 Jan 94 10:52:20 -0500
From: DJ Delorie <dj AT ctron DOT com>
To: stst AT vuse DOT vanderbilt DOT edu
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: emu387 req'd for non-floating point code?

> Everything's fine if I set GO32=emu c:/djgpp/emu387/emu387, but why
> should this be necessary?

gcc itself uses the floating point chip to do certain register
allocation algorithms internally.

> The second problem may be related: everything I compile with DJGPP runs 2
> to 3 fold slower than the corresponding BCC-compiled executable.

Try using -O2 to optimize, and keep in mind that system calls (open,
read, printf) will take longer because information needs to be copied
between real and protected memory.  Large programs, programs that
otherwise need far pointers, and programs doing math with long
integers tend to run faster with gcc.  Also, some I/O programs using
binary files and fread may be faster as djgpp has a larger file buffer
(4k vs 512b) than most 16-bit compilers.


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