Test auto/LB-LRR+R-A+OB-O+OB-O+R-Oc

LISA auto/LB-LRR+R-A+OB-O+OB-O+R-Oc
(*
 * Result: Sometimes
 * P2-P3 rf OB-O: Never->Maybe: Note lack of C11 guarantee, no synchronizes-with
 * P3-P4 rf R-Oc: Note lack of C11 guarantee, control dependency
 * P4 Oc,LRR: Maybe->Sometimes: Control dependencies do not order trailing reads
 *)
{
 4:r4=1;
}
 P0              | P1               | P2            | P3              | P4                 | P5           ;
 r[once] r1 u0   | r[acquire] r1 x1 | r[once] r1 x2 | r[once] r1 x3   | r[once] r1 x4      | w[once] u0 1 ;
 w[release] x1 1 | f[mb]            | f[mb]         | w[release] x4 1 | mov r4 (neq r1 r4) |              ;
                 | w[once] x2 1     | w[once] x3 1  |                 | b[] r4 CTRL4       |              ;
                 |                  |               |                 | r[once] r2 u0      |              ;
                 |                  |               |                 | CTRL4:             |              ;
Observed
    4:r2=0; 4:r1=1; 3:r1=1; 2:r1=1; 1:r1=1; 0:r1=1;