ext/ipp/sources/ippcp/pcpbnu_arith_gcd.c

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/* 
//  Purpose:
//     Intel(R) Integrated Performance Primitives. Cryptography Primitives.
//     Internal Unsigned arithmetic
// 
//  Contents:
//     cpGcd_BNU()
// 
*/

#include "owncp.h"
#include "pcpbnuarith.h"
#include "pcpbnumisc.h"

/*F*
//    Name: cpGcd_BNU
//
// Purpose: compute GCD value.
//
// Returns:
//    GCD value
//
// Parameters:
//    a    source BigNum
//    b    source BigNum
//
*F*/

BNU_CHUNK_T cpGcd_BNU(BNU_CHUNK_T a, BNU_CHUNK_T b)
{
    BNU_CHUNK_T gcd, t, r;

    if(a > b){
        gcd = a;
        t = b;
    } else {
        t = a;
        gcd = b;
    }

    while (t != 0)    {
        r = gcd % t;
        gcd = t;
        t = r;
    }
    return gcd;
}