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