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				/***********************************************************************
				* Copyright (c) 2020 Peter Dettman *
				* Distributed under the MIT software license, see the accompanying *
				* file COPYING or https://www.opensource.org/licenses/mit-license.php.*
				**********************************************************************/

				#ifndef SECP256K1_MODINV32_H
				#define SECP256K1_MODINV32_H

				#if defined HAVE_CONFIG_H
				#include "libsecp256k1-config.h"
				#endif

				#include "util.h"

				/* A signed 30-bit limb representation of integers.
				*
				* Its value is sum(v[i] * 2^(30i), i=0..8). /
				typedef struct {
				int32_t v[9];
				} secp256k1_modinv32_signed30;

				typedef struct {
				/* The modulus in signed30 notation, must be odd and in [3, 2^256]. */
				secp256k1_modinv32_signed30 modulus;

				/* modulus^{-1} mod 2^30 */
				uint32_t modulus_inv30;
				} secp256k1_modinv32_modinfo;

				/* Replace x with its modular inverse mod modinfo->modulus. x must be in range [0, modulus).
				* If x is zero, the result will be zero as well. If not, the inverse must exist (i.e., the gcd of
				* x and modulus must be 1). These rules are automatically satisfied if the modulus is prime.
				*
				* On output, all of x's limbs will be in [0, 2^30).
				*/
				static void secp256k1_modinv32_var(secp256k1_modinv32_signed30 x, const secp256k1_modinv32_modinfo modinfo);

				/* Same as secp256k1_modinv32_var, but constant time in x (not in the modulus). */
				static void secp256k1_modinv32(secp256k1_modinv32_signed30 x, const secp256k1_modinv32_modinfo modinfo);

				#endif /* SECP256K1_MODINV32_H */