if bst > fn lookup tbl

if-vs-fn.lua

local clock = os.goodclock or os.clock

local fns = {
    function(a,b) return a + b end,
    function(a,b) return a - b end,
    function(a,b) return a * b end,
    function(a,b) return a / b end,
    function(a,b) return a ^ b end,
    function(a,b) return b + a end,
    function(a,b) return b - a end,
    function(a,b) return b * a end,
    function(a,b) return b / a end,
    function(a,b) return b ^ a end,
}

(function()
    local cycles = 1e8
    local stime = clock()
    local ops = #fns
    math.randomseed(0)
    for i = 1, cycles do
        local n = math.random(1,ops)
        local a = math.random() * 100
        local b = math.random() * 100
        local ret
        if (n > 5) then
            if (n > 7) then
                if (n == 10) then
                    ret = b ^ a
                elseif (n == 9) then
                    ret = b / a 
                else -- if (n == 8) then
                    ret = b * a
                end
            elseif (n == 7) then
                ret = b - a 
            else -- if (n == 6) then
                ret = b + a
            end
        elseif (n > 2) then
            if (n == 5) then
                ret = a ^ b
            elseif (n == 4) then
                ret = a / b
            else -- if (n == 3) then
                ret = a * b
            end
        elseif (n == 2) then
            ret = a - b
        else -- if (n == 1) then
            ret = a + b
        end
    end
    local etime = clock()
    print("if bst", etime - stime)


    stime = clock()
    local fns = fns
    math.randomseed(0)
    for i = 1, cycles do
        local n = math.random(1,ops)
        local a = math.random() * 100
        local b = math.random() * 100
        local ret = fns[n](a, b)
    end
    etime = clock()

    print("fn", etime - stime)
end)()

output.txt

$ ./tests/if-vs-fn.lua
if bst  3.821662902832
fn      4.4534289836884