GetTriggerUnit() vs locals

02-01-2008, 10:58 AM

What is more efficient:

JASS:

set temp = GetTriggerUnit()
set i = 0
loop
    exitwhen i >= ShieldCounter
    if GetUnitAbilityLevel(temp, ShieldId[i]) > 0 then
        call TriggerExecute(ShieldTrigger[i])
    endif
    set i = i + 1
endloop

JASS:

set i = 0
loop
    exitwhen i >= ShieldCounter
    if GetUnitAbilityLevel(GetTriggerUnit(), ShieldId[i]) > 0 then
        call TriggerExecute(ShieldTrigger[i])
    endif
    set i = i + 1
endloop

I know a lot of you would say the first one:
but what if GetTriggerUnit() native call is somehow inlined by the jass virtual machine? After all it is the most used native of all.

PipeDream?

02-01-2008, 11:03 AM	#2
MaD[Lion]	interesting idea, but the difference wont be tat huge anyway

02-01-2008, 11:10 AM	#3
grim001	correct answer: does not matter

02-01-2008, 11:41 AM	#4
Vexorian	You are comparing GetTriggerUnit + local vs. only GetTriggerUnit, it does not really matter what the vm does. If you would use GetTriggerUnit 4 times or more in the function, I am quite sure that the local would be faster, at least that's what benchmarks showed.

02-01-2008, 12:33 PM

cohadar

Quote:

Originally Posted by Vexorian

If you would use GetTriggerUnit 4 times or more in the function, I am quite sure that the local would be faster, at least that's what benchmarks showed.

Well that is what I was asking for, the benchmark.
kk then will use locals. (for 4 or more times :D)

02-01-2008, 01:19 PM	#6
Vexorian	heh I didn't initially notice it was inside a loop. Edit: And it actually matters if you have 20 GetTriggerUnit() inside an animation timer.

02-02-2008, 05:25 PM	#7
Toadcop	well for small loop amount globals ruls 8-) <=~10 operations, global var would be faster. and + ofc to call a function is slower than to get data from variable (but well in war3 case it's a hash table element.)

02-02-2008, 10:44 PM	#8
cohadar	wtf are you talking about? Noone mentioned any globals.

02-02-2008, 11:27 PM	#9
Toadcop	and ? i am talking about the best solution. who care what the other talking about ? =) // btw the previous was my 1K post :beer:

02-02-2008, 11:35 PM	#10
PipeDream	I think he means that it can be cheaper to use a global than declare a local.

02-03-2008, 12:52 AM	#11
Vexorian	It could be , but it looks like it requires the special case of having few declared globals.