Performance of "for" statement

Does "for" statement computes the condition expressions at each iteration or only once?

To be more specific is there any performance difference between two examples below:

1.

var slice []int{ ... huge list of items... }

for i:=0; i<len(slice); i++ { .... do something ....}

2.

var slice []int{ ... huge list of items... }
sliceLen := len(slice)

for i:=0; i<sliceLen; i++ { .... do something ....}