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.text
.align 2
.globl ___mpn_sub_n
___mpn_sub_n:
movw $-1,tr0 # representation for carry clear
movw pr3,tr2
andw $3,tr2
beq Lend0
subw tr2,pr3
Loop0: rsubw $0,tr0 # restore carry bit from carry-save register
movw (pr1),tr1
subwb (pr2),tr1
movw tr1,(pr0)
subwb tr0,tr0
addw $4,pr0
addw $4,pr1
addw $4,pr2
addw $-1,tr2
bne Loop0
mtstw pr3,pr3
beq Lend
Lend0:
Loop: rsubw $0,tr0 # restore carry bit from carry-save register
movw (pr1),tr1
subwb (pr2),tr1
movw tr1,(pr0)
movw 4(pr1),tr1
subwb 4(pr2),tr1
movw tr1,4(pr0)
movw 8(pr1),tr1
subwb 8(pr2),tr1
movw tr1,8(pr0)
movw 12(pr1),tr1
subwb 12(pr2),tr1
movw tr1,12(pr0)
subwb tr0,tr0
addw $16,pr0
addw $16,pr1
addw $16,pr2
addw $-4,pr3
bne Loop
Lend:
mnegw tr0,pr0
ret
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