+ cmp.ge p10,p11=r16,r24 // access to per_cpu_data?
+ tbit.z p12,p0=r16,61 // access to region 6?
+ mov r25=PERCPU_PAGE_SHIFT << 2
+ mov r26=PERCPU_PAGE_SIZE
+ nop.m 0
+ nop.b 0
+ ;;
+(p10) mov r19=IA64_KR(PER_CPU_DATA)
+(p11) and r19=r19,r16 // clear non-ppn fields