montmulf.h (3097B)
1 /* This Source Code Form is subject to the terms of the Mozilla Public 2 * License, v. 2.0. If a copy of the MPL was not distributed with this 3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 4 5 /* The functions that are to be called from outside of the .s file have the 6 * following interfaces and array size requirements: 7 */ 8 9 void conv_i32_to_d32(double *d32, unsigned int *i32, int len); 10 11 /* Converts an array of int's to an array of doubles, so that each double 12 * corresponds to an int. len is the number of items converted. 13 * Does not allocate the output array. 14 * The pointers d32 and i32 should point to arrays of size at least len 15 * (doubles and unsigned ints, respectively) 16 */ 17 18 void conv_i32_to_d16(double *d16, unsigned int *i32, int len); 19 20 /* Converts an array of int's to an array of doubles so that each element 21 * of the int array is converted to a pair of doubles, the first one 22 * corresponding to the lower (least significant) 16 bits of the int and 23 * the second one corresponding to the upper (most significant) 16 bits of 24 * the 32-bit int. len is the number of ints converted. 25 * Does not allocate the output array. 26 * The pointer d16 should point to an array of doubles of size at least 27 * 2*len and i32 should point an array of ints of size at least len 28 */ 29 30 void conv_i32_to_d32_and_d16(double *d32, double *d16, 31 unsigned int *i32, int len); 32 33 /* Does the above two conversions together, it is much faster than doing 34 * both of those in succession 35 */ 36 37 void mont_mulf_noconv(unsigned int *result, 38 double *dm1, double *dm2, double *dt, 39 double *dn, unsigned int *nint, 40 int nlen, double dn0); 41 42 /* Does the Montgomery multiplication of the numbers stored in the arrays 43 * pointed to by dm1 and dm2, writing the result to the array pointed to by 44 * result. It uses the array pointed to by dt as a temporary work area. 45 * nint should point to the modulus in the array-of-integers representation, 46 * dn should point to its array-of-doubles as obtained as a result of the 47 * function call conv_i32_to_d32(dn, nint, nlen); 48 * nlen is the length of the array containing the modulus. 49 * The representation used for dm1 is the one that is a result of the function 50 * call conv_i32_to_d32(dm1, m1, nlen), the representation for dm2 is the 51 * result of the function call conv_i32_to_d16(dm2, m2, nlen). 52 * Note that m1 and m2 should both be of length nlen, so they should be 53 * padded with 0's if necessary before the conversion. The result comes in 54 * this form (int representation, padded with 0's). 55 * dn0 is the value of the 16 least significant bits of n0'. 56 * The function does not allocate memory for any of the arrays, so the 57 * pointers should point to arrays with the following minimal sizes: 58 * result - nlen+1 59 * dm1 - nlen 60 * dm2 - 2*nlen+1 ( the +1 is necessary for technical reasons ) 61 * dt - 4*nlen+2 62 * dn - nlen 63 * nint - nlen 64 * No two arrays should point to overlapping areas of memory. 65 */