| 1 | # Alpha 21064 __mpn_submul_1 -- Multiply a limb vector with a limb and |
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| 2 | # subtract the result from a second limb vector. |
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| 3 | |
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| 4 | # Copyright (C) 1992-2022 Free Software Foundation, Inc. |
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| 5 | |
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| 6 | # This file is part of the GNU MP Library. |
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| 7 | |
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| 8 | # The GNU MP Library is free software; you can redistribute it and/or modify |
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| 9 | # it under the terms of the GNU Lesser General Public License as published by |
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| 10 | # the Free Software Foundation; either version 2.1 of the License, or (at your |
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| 11 | # option) any later version. |
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| 12 | |
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| 13 | # The GNU MP Library is distributed in the hope that it will be useful, but |
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| 14 | # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
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| 15 | # or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
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| 16 | # License for more details. |
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| 17 | |
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| 18 | # You should have received a copy of the GNU Lesser General Public License |
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| 19 | # along with the GNU MP Library. If not, see <https://www.gnu.org/licenses/>. |
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| 20 | |
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| 21 | |
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| 22 | # INPUT PARAMETERS |
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| 23 | # res_ptr r16 |
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| 24 | # s1_ptr r17 |
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| 25 | # size r18 |
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| 26 | # s2_limb r19 |
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| 27 | |
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| 28 | # This code runs at 42 cycles/limb on EV4 and 18 cycles/limb on EV5. |
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| 29 | |
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| 30 | .set noreorder |
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| 31 | .set noat |
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| 32 | .text |
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| 33 | .align 3 |
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| 34 | .globl __mpn_submul_1 |
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| 35 | .ent __mpn_submul_1 2 |
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| 36 | __mpn_submul_1: |
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| 37 | .frame $30,0,$26 |
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| 38 | |
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| 39 | ldq $2,0($17) # $2 = s1_limb |
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| 40 | addq $17,8,$17 # s1_ptr++ |
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| 41 | subq $18,1,$18 # size-- |
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| 42 | mulq $2,$19,$3 # $3 = prod_low |
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| 43 | ldq $5,0($16) # $5 = *res_ptr |
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| 44 | umulh $2,$19,$0 # $0 = prod_high |
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| 45 | beq $18,.Lend1 # jump if size was == 1 |
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| 46 | ldq $2,0($17) # $2 = s1_limb |
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| 47 | addq $17,8,$17 # s1_ptr++ |
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| 48 | subq $18,1,$18 # size-- |
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| 49 | subq $5,$3,$3 |
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| 50 | cmpult $5,$3,$4 |
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| 51 | stq $3,0($16) |
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| 52 | addq $16,8,$16 # res_ptr++ |
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| 53 | beq $18,.Lend2 # jump if size was == 2 |
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| 54 | |
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| 55 | .align 3 |
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| 56 | .Loop: mulq $2,$19,$3 # $3 = prod_low |
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| 57 | ldq $5,0($16) # $5 = *res_ptr |
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| 58 | addq $4,$0,$0 # cy_limb = cy_limb + 'cy' |
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| 59 | subq $18,1,$18 # size-- |
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| 60 | umulh $2,$19,$4 # $4 = cy_limb |
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| 61 | ldq $2,0($17) # $2 = s1_limb |
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| 62 | addq $17,8,$17 # s1_ptr++ |
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| 63 | addq $3,$0,$3 # $3 = cy_limb + prod_low |
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| 64 | cmpult $3,$0,$0 # $0 = carry from (cy_limb + prod_low) |
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| 65 | subq $5,$3,$3 |
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| 66 | cmpult $5,$3,$5 |
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| 67 | stq $3,0($16) |
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| 68 | addq $16,8,$16 # res_ptr++ |
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| 69 | addq $5,$0,$0 # combine carries |
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| 70 | bne $18,.Loop |
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| 71 | |
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| 72 | .Lend2: mulq $2,$19,$3 # $3 = prod_low |
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| 73 | ldq $5,0($16) # $5 = *res_ptr |
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| 74 | addq $4,$0,$0 # cy_limb = cy_limb + 'cy' |
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| 75 | umulh $2,$19,$4 # $4 = cy_limb |
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| 76 | addq $3,$0,$3 # $3 = cy_limb + prod_low |
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| 77 | cmpult $3,$0,$0 # $0 = carry from (cy_limb + prod_low) |
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| 78 | subq $5,$3,$3 |
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| 79 | cmpult $5,$3,$5 |
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| 80 | stq $3,0($16) |
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| 81 | addq $5,$0,$0 # combine carries |
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| 82 | addq $4,$0,$0 # cy_limb = prod_high + cy |
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| 83 | ret $31,($26),1 |
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| 84 | .Lend1: subq $5,$3,$3 |
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| 85 | cmpult $5,$3,$5 |
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| 86 | stq $3,0($16) |
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| 87 | addq $0,$5,$0 |
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| 88 | ret $31,($26),1 |
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| 89 | |
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| 90 | .end __mpn_submul_1 |
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| 91 | |
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