openpcd/firmware/lib/bitops.h @ master
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.macro bitop, instr |
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| 2 |
and r2, r0, #7 |
| 3 |
mov r3, #1 |
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mov r3, r3, lsl r2 |
| 5 |
save_and_disable_irqs ip |
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ldrb r2, [r1, r0, lsr #3] |
| 7 |
\instr r2, r2, r3 |
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strb r2, [r1, r0, lsr #3] |
| 9 |
restore_irqs ip |
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mov pc, lr |
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.endm |
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|
| 13 |
/**
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| 14 |
* testop - implement a test_and_xxx_bit operation.
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| 15 |
* @instr: operational instruction
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* @store: store instruction
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| 17 |
*
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* Note: we can trivially conditionalise the store instruction
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| 19 |
* to avoid dirting the data cache.
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| 20 |
*/
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| 21 |
.macro testop, instr, store |
| 22 |
add r1, r1, r0, lsr #3 |
| 23 |
and r3, r0, #7 |
| 24 |
mov r0, #1 |
| 25 |
save_and_disable_irqs ip |
| 26 |
ldrb r2, [r1] |
| 27 |
tst r2, r0, lsl r3 |
| 28 |
\instr r2, r2, r0, lsl r3 |
| 29 |
\store r2, [r1] |
| 30 |
restore_irqs ip |
| 31 |
moveq r0, #0 |
| 32 |
mov pc, lr |
| 33 |
.endm |
