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