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#include "crypto_additions.h"
/*
Replace (f,g) with (g,g) if b == 1;
replace (f,g) with (f,g) if b == 0.
Preconditions: b in {0,1}.
*/
void sc_cmov(unsigned char* f, const unsigned char* g, unsigned char b)
{
int count=32;
unsigned char x[32];
for (count=0; count < 32; count++)
x[count] = f[count] ^ g[count];
b = -b;
for (count=0; count < 32; count++)
x[count] &= b;
for (count=0; count < 32; count++)
f[count] = f[count] ^ x[count];
}
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