70543bba37
Exported from SUPERCOP-20200826 using the scripts at: https://github.com/jschanck/pqclean-package-ntruprime
26 lines
576 B
C
26 lines
576 B
C
#include "crypto_encode_857xfreeze3.h"
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#define int16 int16_t
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#define p 857
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/* valid inputs: -16384 <= x < 16384 */
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/* then 3 divides x-F3_freeze(x) */
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/* and F3_freeze(x) is in {-1,0,1} */
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/* all inputs: 3 divides x-F3_freeze(x) */
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/* and F3_freeze(x) is in {-2,-1,0,1,2} */
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static inline unsigned char F3_freeze(int16 x) {
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return x - 3 * ((10923 * x + 16384) >> 15);
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}
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void PQCLEAN_SNTRUP857_CLEAN_crypto_encode_857xfreeze3(unsigned char *s, const void *v) {
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const int16 *r = v;
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int i;
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for (i = 0; i < p; ++i) {
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s[i] = F3_freeze(r[i]);
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}
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}
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