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AArch64 WWC+poxxs+X
"RfeXX PodRWXX RfeXX PodRWXX WseXX"
Cycle=RfeXX PodRWXX RfeXX PodRWXX WseXX
Relax=
Safe=PodRW RfeXX WseXX
Prefetch=1:x=F,1:y=W,2:y=F,2:x=W
Com=Rf Rf Ws
Orig=RfeXX PodRWXX RfeXX PodRWXX WseXX
{ ok=1;
0:X0=x; 0:X5=ok;
1:X0=x; 1:X3=y; 1:X7=ok;
2:X0=y; 2:X3=x; 2:X7=ok;
}
P0 | P1 | P2 ;
MOV W1,#2 | LDXR W1,[X0] | LDXR W1,[X0] ;
LDXR W2,[X0] | STXR W2,W1,[X0] | STXR W2,W1,[X0] ;
STXR W3,W1,[X0] | CBNZ W2,Fail1 | CBNZ W2,Fail2 ;
CBNZ W3,Fail0 | MOV W4,#1 | MOV W4,#1 ;
B Exit0 | LDXR W5,[X3] | LDXR W5,[X3] ;
Fail0: | STXR W2,W4,[X3] | STXR W2,W4,[X3] ;
MOV W4,#0 | CBNZ W2,Fail1 | CBNZ W2,Fail2 ;
STR W4,[X5] | B Exit1 | B Exit2 ;
Exit0: | Fail1: | Fail2: ;
| MOV W6,#0 | MOV W6,#0 ;
| STR W6,[X7] | STR W6,[X7] ;
| Exit1: | Exit2: ;
Observed
y=1; x=2; ok=1; 2:X5=0; 2:X1=1; 1:X5=0; 1:X1=2; 0:X2=1;
and y=1; x=2; ok=1; 2:X5=0; 2:X1=1; 1:X5=0; 1:X1=1; 0:X2=1;
and y=1; x=1; ok=0; 2:X5=0; 2:X1=1; 1:X5=0; 1:X1=1; 0:X2=1;
and y=1; x=1; ok=1; 2:X5=2; 2:X1=1; 1:X5=0; 1:X1=1; 0:X2=0;
and y=1; x=1; ok=0; 2:X5=0; 2:X1=1; 1:X5=0; 1:X1=1; 0:X2=0;