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#if __LINUX_ARM_ARCH__ >= 6
.macro bitop, instr
mov r2, #1
and r3, r0, #7 @ Get bit offset
add r1, r1, r0, lsr #3 @ Get byte offset
mov r3, r2, lsl r3
1: ldrexb r2, [r1]
\instr r2, r2, r3
strexb r0, r2, [r1]
cmpne r0, #0
bne 1b
mov pc, lr
.endm
.macro testop, instr, store
and r3, r0, #7 @ Get bit offset
mov r2, #1
add r1, r1, r0, lsr #3 @ Get byte offset
mov r3, r2, lsl r3 @ create mask
1: ldrexb r2, [r1]
ands r0, r2, r3 @ save old value of bit
\instr r2, r2, r3 @ toggle bit
strexb ip, r2, [r1]
cmp ip, #0
bne 1b
cmp r0, #0
movne r0, #1
2: mov pc, lr
.endm
#else
.macro bitop, instr
and r2, r0, #7
mov r3, #1
mov r3, r3, lsl r2
save_and_disable_irqs ip, r2
ldrb r2, [r1, r0, lsr #3]
\instr r2, r2, r3
strb r2, [r1, r0, lsr #3]
restore_irqs ip
mov pc, lr
.endm
/**
* testop - implement a test_and_xxx_bit operation.
* @instr: operational instruction
* @store: store instruction
*
* Note: we can trivially conditionalise the store instruction
* to avoid dirting the data cache.
*/
.macro testop, instr, store
add r1, r1, r0, lsr #3
and r3, r0, #7
mov r0, #1
save_and_disable_irqs ip, r2
ldrb r2, [r1]
tst r2, r0, lsl r3
\instr r2, r2, r0, lsl r3
\store r2, [r1]
restore_irqs ip
moveq r0, #0
mov pc, lr
.endm
#endif
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