github.com/aergoio/aergo@v1.3.1/libtool/src/gmp-6.1.2/mpn/cray/ieee/mul_basecase.c (about) 1 /* Cray PVP/IEEE mpn_mul_basecase. 2 3 Copyright 2000, 2001 Free Software Foundation, Inc. 4 5 This file is part of the GNU MP Library. 6 7 The GNU MP Library is free software; you can redistribute it and/or modify 8 it under the terms of either: 9 10 * the GNU Lesser General Public License as published by the Free 11 Software Foundation; either version 3 of the License, or (at your 12 option) any later version. 13 14 or 15 16 * the GNU General Public License as published by the Free Software 17 Foundation; either version 2 of the License, or (at your option) any 18 later version. 19 20 or both in parallel, as here. 21 22 The GNU MP Library is distributed in the hope that it will be useful, but 23 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 24 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 25 for more details. 26 27 You should have received copies of the GNU General Public License and the 28 GNU Lesser General Public License along with the GNU MP Library. If not, 29 see https://www.gnu.org/licenses/. */ 30 31 /* The most critical loop of this code runs at about 5 cycles/limb on a T90. 32 That is not perfect, mainly due to vector register shortage. */ 33 34 #include <intrinsics.h> 35 #include "gmp.h" 36 #include "gmp-impl.h" 37 38 void 39 mpn_mul_basecase (mp_ptr rp, 40 mp_srcptr up, mp_size_t un, 41 mp_srcptr vp, mp_size_t vn) 42 { 43 mp_limb_t cy[un + vn]; 44 mp_limb_t vl; 45 mp_limb_t a, b, r, s0, s1, c0, c1; 46 mp_size_t i, j; 47 int more_carries; 48 49 for (i = 0; i < un + vn; i++) 50 { 51 rp[i] = 0; 52 cy[i] = 0; 53 } 54 55 #pragma _CRI novector 56 for (j = 0; j < vn; j++) 57 { 58 vl = vp[j]; 59 60 a = up[0] * vl; 61 r = rp[j]; 62 s0 = a + r; 63 rp[j] = s0; 64 c0 = ((a & r) | ((a | r) & ~s0)) >> 63; 65 cy[j] += c0; 66 67 #pragma _CRI ivdep 68 for (i = 1; i < un; i++) 69 { 70 a = up[i] * vl; 71 b = _int_mult_upper (up[i - 1], vl); 72 s0 = a + b; 73 c0 = ((a & b) | ((a | b) & ~s0)) >> 63; 74 r = rp[j + i]; 75 s1 = s0 + r; 76 rp[j + i] = s1; 77 c1 = ((s0 & r) | ((s0 | r) & ~s1)) >> 63; 78 cy[j + i] += c0 + c1; 79 } 80 rp[j + un] = _int_mult_upper (up[un - 1], vl); 81 } 82 83 more_carries = 0; 84 #pragma _CRI ivdep 85 for (i = 1; i < un + vn; i++) 86 { 87 r = rp[i]; 88 c0 = cy[i - 1]; 89 s0 = r + c0; 90 rp[i] = s0; 91 c0 = (r & ~s0) >> 63; 92 more_carries += c0; 93 } 94 /* If that second loop generated carry, handle that in scalar loop. */ 95 if (more_carries) 96 { 97 mp_limb_t cyrec = 0; 98 for (i = 1; i < un + vn; i++) 99 { 100 r = rp[i]; 101 c0 = (r < cy[i - 1]); 102 s0 = r + cyrec; 103 rp[i] = s0; 104 c1 = (r & ~s0) >> 63; 105 cyrec = c0 | c1; 106 } 107 } 108 }