1. A method of operating a processor, the method comprising: in response to a load-and-flag instruction that specifies a load source as an operand, acquiring ownership of a set of addressable storage locations, wherein the acquired set comprises the load source; subsequent to said acquiring, in response to a first instance of a conditional-store instruction that specifies a first store target as an operand, storing a first result to the first store target if the acquired set remains owned and contents thereof remain unmodified since said acquiring; and in response to a subsequent instance of the conditional-store instruction that specifies a second store target as an operand, storing a second result to the second store target if the acquired set remains owned and contents thereof remain unmodified since said acquiring; wherein the first store target and the second store target are different addressable storage locations.