1/* Alpha sub_n -- Subtract two limb vectors of the same length > 0 and 2 * store difference in a third limb vector. 3 * Copyright (C) 1995, 1998, 4 * 2001, 2002 Free Software Foundation, Inc. 5 * 6 * This file is part of Libgcrypt. 7 * 8 * Libgcrypt is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU Lesser General Public License as 10 * published by the Free Software Foundation; either version 2.1 of 11 * the License, or (at your option) any later version. 12 * 13 * Libgcrypt is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA 21 */ 22 23 24/******************* 25 * mpi_limb_t 26 * _gcry_mpih_sub_n( mpi_ptr_t res_ptr, (r16) 27 * mpi_ptr_t s1_ptr, (r17) 28 * mpi_ptr_t s2_ptr, (r18) 29 * mpi_size_t size) (r19) 30 */ 31 32 .set noreorder 33 .set noat 34.text 35 .align 3 36 .globl _gcry_mpih_sub_n 37 .ent _gcry_mpih_sub_n 38_gcry_mpih_sub_n: 39 .frame $30,0,$26,0 40 41 ldq $3,0($17) 42 ldq $4,0($18) 43 44 subq $19,1,$19 45 and $19,4-1,$2 # number of limbs in first loop 46 bis $31,$31,$0 47 beq $2,.L0 # if multiple of 4 limbs, skip first loop 48 49 subq $19,$2,$19 50 51.Loop0: subq $2,1,$2 52 ldq $5,8($17) 53 addq $4,$0,$4 54 ldq $6,8($18) 55 cmpult $4,$0,$1 56 subq $3,$4,$4 57 cmpult $3,$4,$0 58 stq $4,0($16) 59 or $0,$1,$0 60 61 addq $17,8,$17 62 addq $18,8,$18 63 bis $5,$5,$3 64 bis $6,$6,$4 65 addq $16,8,$16 66 bne $2,.Loop0 67 68.L0: beq $19,.Lend 69 70 .align 3 71.Loop: subq $19,4,$19 72 73 ldq $5,8($17) 74 addq $4,$0,$4 75 ldq $6,8($18) 76 cmpult $4,$0,$1 77 subq $3,$4,$4 78 cmpult $3,$4,$0 79 stq $4,0($16) 80 or $0,$1,$0 81 82 ldq $3,16($17) 83 addq $6,$0,$6 84 ldq $4,16($18) 85 cmpult $6,$0,$1 86 subq $5,$6,$6 87 cmpult $5,$6,$0 88 stq $6,8($16) 89 or $0,$1,$0 90 91 ldq $5,24($17) 92 addq $4,$0,$4 93 ldq $6,24($18) 94 cmpult $4,$0,$1 95 subq $3,$4,$4 96 cmpult $3,$4,$0 97 stq $4,16($16) 98 or $0,$1,$0 99 100 ldq $3,32($17) 101 addq $6,$0,$6 102 ldq $4,32($18) 103 cmpult $6,$0,$1 104 subq $5,$6,$6 105 cmpult $5,$6,$0 106 stq $6,24($16) 107 or $0,$1,$0 108 109 addq $17,32,$17 110 addq $18,32,$18 111 addq $16,32,$16 112 bne $19,.Loop 113 114.Lend: addq $4,$0,$4 115 cmpult $4,$0,$1 116 subq $3,$4,$4 117 cmpult $3,$4,$0 118 stq $4,0($16) 119 or $0,$1,$0 120 ret $31,($26),1 121 122 .end _gcry_mpih_sub_n 123 124 125