}
	return c
}

// isLeaf reports whether f performs any calls.
func isLeaf(f *Func) bool {
	for _, b := range f.Blocks {
		for _, v := range b.Values {
			if v.Op.IsCall() && !v.Op.IsTailCall() {
				// tail call is not counted as it does not save the return PC or need a frame
				return false
			}
		}
	}
	return true
}

// needRegister reports whether v needs a register.