Function/method argument validation standards

I was just inquiring about standard practices of argument validation syntax. I'm working with PHP as of currently, but anything that's considered a platform/language agnostic solution would be great.

As of currently, I'm aware of two pretty common syntax. For example (my preference):

function foo($a, $b, $c){
    if(!$a){ throw new Exception(); }
    if($b < 0){ throw new Exception(); }
    if(!check($c)){ throw new Exception(); }

    //do stuff with $a, $b, and $c

}

And alternatively:

function foo($a, $b, $c){
    if($a){
        if($b >= 0){
            if(check($c)){

                //do stuff with $a, $b, and $c

            }else{ throw new Exception(); }
        }else{ throw new Exception(); }
    }else{ throw new Exception(); }
}

In any case, if anyone knows of documentation that illustrates any sort of standards, or common practices regarding this, I would greatly appreciate a reference.

Of course, personal preferences and opinions are more then welcome, but reasoning for your choices would be an asset.