22 lines
524 B
ArmAsm
22 lines
524 B
ArmAsm
.text
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.align 4
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.globl ___mpn_sub_n
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___mpn_sub_n:
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mov 1,g6 # set carry-save register
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cmpo 1,0 # clear cy
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Loop: subo 1,g3,g3 # update loop counter
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ld (g1),g5 # load from s1_ptr
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addo 4,g1,g1 # s1_ptr++
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ld (g2),g4 # load from s2_ptr
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addo 4,g2,g2 # s2_ptr++
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cmpo g6,1 # restore cy from g6, relies on cy being 0
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subc g4,g5,g4 # main subtract
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subc 0,0,g6 # save cy in g6
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st g4,(g0) # store result to res_ptr
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addo 4,g0,g0 # res_ptr++
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cmpobne 0,g3,Loop # when branch is taken, cy will be 0
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mov g6,g0
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ret
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