[
Home
]
[ Index:
by date
|
by threads
]
[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
Date: | 2010-04-29 (18:34) |
From: | Eray Ozkural <examachine@g...> |
Subject: | min function, why is it so slow? |
Hello there, Although I turn on inlining in ocamlopt (-inline 10), I think that the min function is not quite inlined. Indeed, it's faster if I just inline it myself (if a<b a then a else b). It's almost twice as fast this way. Which makes me thinking. I suppose a procedure call cost is incurred. This doesn't change when I define min for two parameters myself in another module. What do you think I am doing wrong? In the following, the first loop is (more than) twice as slow, where min is defined as let min a b = if a <= b then a else b for i=1 to 10000000 do x1 := !x1 + (Util.min a1.(i-1) a1.(i)); done for i=1 to 10000000 do x1 := !x1 + (if a1.(i-1) <= a1.(i) then a1.(i-1) else a1.(i)) Time elapsed: 0.189798 (first loop) Time elapsed: 0.079624 (second loop) Can someone please explain to me what's going on here? Perhaps there is inlining, but after inlining, some optimization passes aren't performed? Best, -- Eray Ozkural, PhD candidate. Comp. Sci. Dept., Bilkent University, Ankara http://groups.yahoo.com/group/ai-philosophy http://myspace.com/arizanesil http://myspace.com/malfunct