challenge.txt

ROM:510147C8 get_cpu_aff
ROM:510147C8                 MRC             p15, 0, R0,c0,c0, 5
ROM:510147CC                 AND.W           R0, R0, #0xF
ROM:510147D0                 BX              LR
ROM:510147D0 ; End of function get_cpu_aff



ROM:51014810 wait_field0_zero_and_set_field0
ROM:51014810                 LDREX.W         R1, [R0]
ROM:51014814                 CBNZ            R1, loc_51014822
ROM:51014816                 STREX.W         R1, LR, [R0]
ROM:5101481A                 CBNZ            R1, loc_51014824
ROM:5101481C                 DMB.W           SY
ROM:51014820                 BX              LR
ROM:51014822 ; ---------------------------------------------------------------------------
ROM:51014822
ROM:51014822 loc_51014822
ROM:51014822                 WFE
ROM:51014824
ROM:51014824 loc_51014824
ROM:51014824                 B               wait_field0_zero_and_set_field0
ROM:51014824 ; End of function wait_field0_zero_and_set_field0



ROM:510145F4 atomic_dec
ROM:510145F4                 DMB             SY
ROM:510145F8
ROM:510145F8 loc_510145F8
ROM:510145F8                 LDREXH          R2, [R0]
ROM:510145FC                 SUB             R3, R2, R1
ROM:51014600                 STREXH          R12, R3, [R0]
ROM:51014604                 TEQ             R12, #0
ROM:51014608                 BNE             loc_510145F8
ROM:5101460C                 DMB             SY
ROM:51014610                 SXTH            R0, R2
ROM:51014614                 BX              LR
ROM:51014614 ; End of function atomic_dec



ROM:51014828 zero_field0
ROM:51014828                 MOVS            R1, #0
ROM:5101482A                 DMB.W           SY
ROM:5101482E                 STR             R1, [R0]
ROM:51014830                 DSB.W           SY
ROM:51014834                 SEV
ROM:51014836                 BX              LR
ROM:51014836 ; End of function zero_field0



ROM:5101490C cpu_barrier_start
ROM:5101490C                 PUSH            {R3-R5,LR}
ROM:5101490E                 MOV             R4, R0
ROM:51014910                 MOV             R5, R1
ROM:51014912                 BL              get_cpu_aff
ROM:51014916                 DMB.W           SY
ROM:5101491A                 CMP             R0, R5
ROM:5101491C                 BEQ             loc_5101493C
ROM:5101491E                 LDRH            R3, [R4,#6]
ROM:51014920                 SXTH            R2, R0
ROM:51014922                 ADDS            R1, R4, #6
ROM:51014924                 SXTH            R3, R3
ROM:51014926                 CMP             R2, R3
ROM:51014928                 BEQ             loc_51014934
ROM:5101492A
ROM:5101492A loc_5101492A
ROM:5101492A                 WFE
ROM:5101492C                 LDRH            R3, [R1]
ROM:5101492E                 SXTH            R3, R3
ROM:51014930                 CMP             R3, R2
ROM:51014932                 BNE             loc_5101492A
ROM:51014934
ROM:51014934 loc_51014934
ROM:51014934                 MOV             R0, R4
ROM:51014936                 BL              wait_field0_zero_and_set_field0
ROM:5101493A                 POP             {R3-R5,PC}
ROM:5101493C ; ---------------------------------------------------------------------------
ROM:5101493C
ROM:5101493C loc_5101493C
ROM:5101493C                 STRH            R0, [R4,#6]
ROM:5101493E                 POP             {R3-R5,PC}
ROM:5101493E ; End of function cpu_barrier_start



ROM:51014940 cpu_barrier_end
ROM:51014940                 PUSH            {R4-R6,LR}
ROM:51014942                 MOV             R5, R0
ROM:51014944                 BL              get_cpu_aff
ROM:51014948                 ADDS            R0, #1
ROM:5101494A                 CMP             R0, #4
ROM:5101494C                 ITE NE
ROM:5101494E                 UXTHNE          R0, R0
ROM:51014950                 MOVEQ           R0, #0
ROM:51014952                 DMB.W           SY
ROM:51014956                 ADDS            R4, R5, #4
ROM:51014958                 STRH            R0, [R5,#6]
ROM:5101495A                 MOVS            R1, #1
ROM:5101495C                 MOV             R0, R4
ROM:5101495E                 BLX             atomic_dec
ROM:51014962                 MOV             R6, R0
ROM:51014964                 MOV             R0, R5
ROM:51014966                 BL              zero_field0
ROM:5101496A                 DSB.W           SY
ROM:5101496E                 SEV
ROM:51014970                 CMP             R6, #4
ROM:51014972                 LDRH            R3, [R5,#4]
ROM:51014974                 BEQ             loc_51014988
ROM:51014976                 CMP             R3, #4
ROM:51014978                 BEQ             locret_510149A0
ROM:5101497A
ROM:5101497A loc_5101497A
ROM:5101497A                 WFE
ROM:5101497C                 LDRH            R3, [R4]
ROM:5101497E                 CMP             R3, #4
ROM:51014980                 BNE             loc_5101497A
ROM:51014982                 POP             {R4-R6,PC}
ROM:51014984 ; ---------------------------------------------------------------------------
ROM:51014984
ROM:51014984 loc_51014984
ROM:51014984                 WFE
ROM:51014986                 LDRH            R3, [R4]
ROM:51014988
ROM:51014988 loc_51014988
ROM:51014988                 SXTH            R3, R3
ROM:5101498A                 CMP             R3, #0
ROM:5101498C                 BGT             loc_51014984
ROM:5101498E                 MOVS            R3, #4
ROM:51014990                 MOVS            R2, #1
ROM:51014992                 STR             R2, [R5]
ROM:51014994                 STRH            R3, [R5,#4]
ROM:51014996                 STRH            R3, [R5,#6]
ROM:51014998                 DSB.W           SY
ROM:5101499C                 SEV
ROM:5101499E                 POP             {R4-R6,PC}
ROM:510149A0 ; ---------------------------------------------------------------------------
ROM:510149A0
ROM:510149A0 locret_510149A0
ROM:510149A0                 POP             {R4-R6,PC}
ROM:510149A0 ; End of function cpu_barrier_end