ack/mach/powerpc/libem/inn.s

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ArmAsm
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#
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.sect .text
/* Tests a bit in a bitset on the stack.
*
* Stack: ( bitset bitnum setsize -- bool )
*/
.define .inn
.inn:
lwz r3, 0(sp) /* r3 = size (bytes) */
lwz r4, 4(sp) /* r4 = bit number */
addi r5, sp, 8 /* r5 = base address of bit set */
rlwinm r6, r4, 29, 3, 29 /* r6 = byte index of word in set */
extrwi r7, r4, 5, 27 /* r7 = bit number within word */
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lwzx r8, r5, r6 /* r8 = individual word from set */
srw r8, r8, r7
extrwi r8, r8, 1, 31
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addi sp, sp, 8 /* retract over the two words */
add sp, sp, r3 /* retract over bitfield */
stwu r8, -4(sp) /* push result */
blr /* return */