ff-cl-gen

OpenCL code generator for finite-field arithmetic over prime fields constructed with Rust ff library.

Notes: - Limbs are 64-bit long. - The library assumes that the most significant bit of your prime-field is unset. This allows for cheap reductions.

Usage

Generating OpenCL codes for Bls12-381 Fr elements:

rust use paired::bls12_381::Fr; let src = ff_cl_gen::field::<Fr>("Fr");

Generated interface (FIELD is substituted with Fr):

```c typedef ulong limb;

define LIMB_BITS (64)

define FIELD_LIMBS ... // Number of 64bit limbs for this field

define FIELD_P ... // Normal form of field modulus

define FIELD_ONE ... // Montomery form of one

define FIELD_ZERO ... // Montomery/normal form of zero

define FIELDBITS (FIELDLIMBS * LIMB_BITS)

typedef struct { limb val[FIELD_LIMBS]; } FIELD;

bool FIELDgte(FIELD a, FIELD b); // Greater than or equal bool FIELDeq(FIELD a, FIELD b); // Equal FIELD FIELDsub(FIELD a, FIELD b); // Modular subtraction FIELD FIELDadd(FIELD a, FIELD b); // Modular addition FIELD FIELDmul(FIELD a, FIELD b); // Modular multiplication FIELD FIELDsqr(FIELD a); // Modular squaring FIELD FIELDdouble(FIELD a); // Modular doubling FIELD FIELDpow(FIELD base, uint exponent); // Modular power FIELD FIELDpowlookup(global FIELD *bases, uint exponent); // Modular power with lookup table for bases FIELD FIELDmont(FIELD a); // To montgomery form FIELD FIELDunmont(FIELD a); // To regular form bool FIELDgetbit(FIELD l, uint i); // Get ith bit (From most significant digit) uint FIELDgetbits(FIELD l, uint skip, uint window); // Get window consecutive bits, (Starting from skipth bit from most significant digit) ```

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.