1 dnl IBM POWER mpn_sub_n -- Subtract two limb vectors of equal, non-zero
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29 include(`../config.m4')
33 andil. 10,6,1 C odd or even number of limbs?
34 l 8,0(4) C load least significant s1 limb
35 l 0,0(5) C load least significant s2 limb
36 cal 3,-4(3) C offset res_ptr, it's updated before it's used
37 sri 10,6,1 C count for unrolled loop
38 sf 7,0,8 C subtract least significant limbs, set cy
39 mtctr 10 C copy count into CTR
40 beq 0,Leven C branch if even # of limbs (# of limbs >= 2)
42 C We have an odd # of limbs. Add the first limbs separately.
43 cmpi 1,10,0 C is count for unrolled loop zero?
44 bc 4,6,L1 C bne cr1,L1 (misassembled by gas)
46 sfe 3,0,0 C load !cy into ...
47 sfi 3,3,0 C ... return value register
50 C We added least significant limbs. Now reload the next limbs to enter loop.
51 L1: lu 8,4(4) C load s1 limb and update s1_ptr
52 lu 0,4(5) C load s2 limb and update s2_ptr
54 sfe 7,0,8 C subtract limbs, set cy
55 Leven: lu 9,4(4) C load s1 limb and update s1_ptr
56 lu 10,4(5) C load s2 limb and update s2_ptr
57 bdz Lend C If done, skip loop
59 Loop: lu 8,4(4) C load s1 limb and update s1_ptr
60 lu 0,4(5) C load s2 limb and update s2_ptr
61 sfe 11,10,9 C subtract previous limbs with cy, set cy
63 lu 9,4(4) C load s1 limb and update s1_ptr
64 lu 10,4(5) C load s2 limb and update s2_ptr
65 sfe 7,0,8 C subtract previous limbs with cy, set cy
67 bdn Loop C decrement CTR and loop back
69 Lend: sfe 11,10,9 C subtract limbs with cy, set cy
72 sfe 3,0,0 C load !cy into ...
73 sfi 3,3,0 C ... return value register