OpenEuphoria

Re: Good Use of GOTO

• Posted by Jeremy Cowgar <jeremy at ?owgar.?om> Jun 06, 2008
• 809 views

Ok, here are the benchmarks you asked for CK...


[jeremy@jdesk 40goto]$ time exu ffunc.e 

real    0m2.424s
user    0m2.420s
sys     0m0.003s
[jeremy@jdesk 40goto]$ time exu fgoto.e 

real    0m1.142s
user    0m1.143s
sys     0m0.000s

The code is:

ffunc.e  (factorial function)

function factorial(atom a)
	if a < 2 then
		return a
	end if
	return a*factorial(a-1)
end function

object ign

for i = 1 to 1000000 do
	ign = factorial(20)
end for

and

fgoto.e (factorial goto)

function factorial(atom a)
	atom b 
	b = a 
	 
label "start" 
	if a <= 2 then 
		goto "end" 
	end if 
	 
	a = a - 1 
	b = b * a 
	goto "start" 
	 
label "end" 
	return b 
end function 

object ign

for i = 1 to 1000000 do
	ign = factorial(20)
end for

Now, bear in mind, this is an optimization. The non-goto version of factorial is
much simpler, but also much slower. You would only resort to a situation like
this if you have measured speed and speed was not acceptable for your situation.

Goto has been committed as a branch (not part of trunk everyone!) you can
download it, compile and run these benchmarks for yourself. The SVN repo is:

http://rapideuphoria.svn.sourceforge.net/svnroot/rapideuphoria

--
Jeremy Cowgar
http://jeremy.cowgar.com