This patch adds handling of the long_call, far, and near attributes passed by front-end. The patch depends on D35479.
Some minor nits. Also, see my question inline.
Restore the comment from lines 3156-3157 to an appropriate place.
Question (I haven't looked throughly yet): Can an ExternalSymbolSDNode have the long-call/near-call attribute?
If it can, then this expansion code is missing the portions that check the attributes of the ExternalSymbolSDNode.
Also requires testing for mips64.
; CHECK-LABEL: foo: before this.