1 /* mpz_mul_ui/si (product, multiplier, small_multiplicand) -- Set PRODUCT to 2 MULTIPLICATOR times SMALL_MULTIPLICAND. 3 4 Copyright 1991, 1993, 1994, 1996, 2000, 2001, 2002, 2005, 2008 Free Software 5 Foundation, Inc. 6 7 This file is part of the GNU MP Library. 8 9 The GNU MP Library is free software; you can redistribute it and/or modify 10 it under the terms of the GNU Lesser General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or (at your 12 option) any later version. 13 14 The GNU MP Library is distributed in the hope that it will be useful, but 15 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 16 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 17 License for more details. 18 19 You should have received a copy of the GNU Lesser General Public License 20 along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ 21 22 #include "gmp.h" 23 #include "gmp-impl.h" 24 25 26 #ifdef OPERATION_mul_si 27 #define FUNCTION mpz_mul_si 28 #define MULTIPLICAND_UNSIGNED 29 #define MULTIPLICAND_ABS(x) ((unsigned long) ABS(x)) 30 #endif 31 32 #ifdef OPERATION_mul_ui 33 #define FUNCTION mpz_mul_ui 34 #define MULTIPLICAND_UNSIGNED unsigned 35 #define MULTIPLICAND_ABS(x) x 36 #endif 37 38 #ifndef FUNCTION 39 Error, error, unrecognised OPERATION 40 #endif 41 42 43 void 44 FUNCTION (mpz_ptr prod, mpz_srcptr mult, 45 MULTIPLICAND_UNSIGNED long int small_mult) 46 { 47 mp_size_t size = SIZ(mult); 48 mp_size_t sign_product = size; 49 mp_limb_t sml; 50 mp_limb_t cy; 51 mp_ptr pp; 52 53 if (size == 0 || small_mult == 0) 54 { 55 SIZ(prod) = 0; 56 return; 57 } 58 59 size = ABS (size); 60 61 sml = MULTIPLICAND_ABS (small_mult); 62 63 if (sml <= GMP_NUMB_MAX) 64 { 65 MPZ_REALLOC (prod, size + 1); 66 pp = PTR(prod); 67 cy = mpn_mul_1 (pp, PTR(mult), size, sml & GMP_NUMB_MASK); 68 pp[size] = cy; 69 size += cy != 0; 70 } 71 #if GMP_NAIL_BITS != 0 72 else 73 { 74 /* Operand too large for the current nails size. Use temporary for 75 intermediate products, to allow prod and mult being identical. */ 76 mp_ptr tp; 77 TMP_DECL; 78 TMP_MARK; 79 80 tp = TMP_ALLOC_LIMBS (size + 2); 81 82 cy = mpn_mul_1 (tp, PTR(mult), size, sml & GMP_NUMB_MASK); 83 tp[size] = cy; 84 cy = mpn_addmul_1 (tp + 1, PTR(mult), size, sml >> GMP_NUMB_BITS); 85 tp[size + 1] = cy; 86 size += 2; 87 MPN_NORMALIZE_NOT_ZERO (tp, size); /* too general, need to trim one or two limb */ 88 MPZ_REALLOC (prod, size); 89 pp = PTR(prod); 90 MPN_COPY (pp, tp, size); 91 TMP_FREE; 92 } 93 #endif 94 95 SIZ(prod) = ((sign_product < 0) ^ (small_mult < 0)) ? -size : size; 96 } 97