Newsgroups:	comp.os.msdos.djgpp
From:	"Pin F. Sun" <pfsun AT undergrad DOT math DOT uwaterloo DOT ca>
Subject:	Is DJGPP that efficient?
Sender:	news AT undergrad DOT math DOT uwaterloo DOT ca (news spool owner)
Message-ID:	<32B0ACD2.41C6@undergrad.math.uwaterloo.ca>
Date:	Fri, 13 Dec 1996 01:09:38 GMT
Nntp-Posting-Host:	zeno23.math.uwaterloo.ca
Mime-Version:	1.0
Organization:	University of Waterloo
Lines:	21
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

I just changed some heavily used mathematical functions to assembly,
surprisingly, the performance gain is only 10%.  I fully optimized
the assembly codes according to the floating point rules to make sure
each mul and add only takes one cycle, but for a function that involves
15 muls and 30 adds the performance gain is 10%.  Is it because DJGPP
is so efficient that I shouldn't bother to code in assembly? or 10% is
actually a reasonable increase?  I used inline assembly, is there any
tricks that I don't know about for inline assembly(it's not that I know
any, but what kind of tricks could be there??)  I also tried to write
an external assembly routine, but MASM reported trillions of errors when
I changed the memory mode to flat(it was a working assembly routine when
I used memory mode small & large).  I've never worked with flat mode
assembly before, sorry if this is something out of the topic, is there
anything else I should do other than just switched the keyword? 

by the way, I've heard about win32gcc in this newsgroup, what is it?
Where can I get it?

thanks,

P. Sun

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