[Overtaxed]

what exactly did Gandalf say to the wargs up there?

Bad dogs! Bad! Why not? I'm already in the Corner!

[Tuor]

what exactly did Gandalf say to the wargs up there?

That wasn't to the Wargs, if you're asking about the Elvish he was speaking (Sindarian). He was casting a spell...a spell of fire that ignited the trees.

Tuor