ack/mach/powerpc/libem/set.s

30 lines
598 B
ArmAsm
Raw Normal View History

#include "powerpc.h"
.sect .text
! Create singleton set.
! Stack: ( -- set )
! With r3 = size of set, r4 = bit number
.define .set
.set:
rlwinm r7, r3, 30, 2, 31
neg r5, r3
add sp, sp, r5 ! allocate set
mr r6, sp ! r6 = ptr to set
mtspr ctr, r7 ! ctr = r3 / 4
1:
rlwinm. r7, r4, 0, 0, 26 ! r7 = r4 & ~31
bc IFTRUE, EQ, 2f ! branch if r4 in 0..31
addi r5, r0, 0 ! no bit, word is zero
b 3f
2:
addi r5, r0, 1
slw r5, r5, r4 ! yes bit, set bit in word
3:
stw r5, 0(r6) ! store word in set
addi r4, r4, -32
addi r6, r6, 4
bc DNZ, 0, 1b ! loop ctr times
bclr ALWAYS, 0, 0