2 * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
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29 br_i32_reduce(uint32_t *x, const uint32_t *a, const uint32_t *m)
31 uint32_t m_bitlen, a_bitlen;
35 mlen = (m_bitlen + 31) >> 5;
43 * If the source is shorter, then simply copy all words from a[]
44 * and zero out the upper words.
47 alen = (a_bitlen + 31) >> 5;
48 if (a_bitlen < m_bitlen) {
49 memcpy(x + 1, a + 1, alen * sizeof *a);
50 for (u = alen; u < mlen; u ++) {
57 * The source length is at least equal to that of the modulus.
58 * We must thus copy N-1 words, and input the remaining words
61 memcpy(x + 1, a + 2 + (alen - mlen), (mlen - 1) * sizeof *a);
63 for (u = 1 + alen - mlen; u > 0; u --) {
64 br_i32_muladd_small(x, a[u], m);