Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

check-noat.ll
; RUN: llc -march=mipsel < %s | FileCheck %s 

define void @f() nounwind readnone {
entry:
; CHECK-LABEL: f:
; CHECK: .set  noat
; CHECK: .set  at

  ret void
}