Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

pr28547.s
// RUN: llvm-mc -triple x86_64-unknown-unknown %s
	.intel_syntax
ones:
	.float +1.0, +1.0, +1.0, +1.0
	vmovaps xmm15, xmmword ptr [rip+ones] # +1.0, +1.0, +1.0, +1.0