carry3
int64_t carry3;
carry3 = (s3 + (1 << 20)) >> 21;
s4 += carry3;
s3 -= int64_lshift21(carry3);
carry3 = s3 >> 21;
s4 += carry3;
s3 -= int64_lshift21(carry3);
carry3 = s3 >> 21;
s4 += carry3;
s3 -= int64_lshift21(carry3);
int64_t carry3;
carry3 = h3 + (1 << 24);
h4 += carry3 >> 25;
h3 -= carry3 & kTop39Bits;
int64_t carry3;
carry3 = h3 + (1 << 24);
h4 += carry3 >> 25;
h3 -= carry3 & kTop39Bits;
int64_t carry3;
carry3 = h3 + (1 << 24);
h4 += carry3 >> 25;
h3 -= carry3 & kTop39Bits;
int64_t carry3;
carry3 = h3 + (1 << 24);
h4 += carry3 >> 25;
h3 -= carry3 & kTop39Bits;
int64_t carry3;
carry3 = (s3 + (1 << 20)) >> 21;
s4 += carry3;
s3 -= carry3 * (1 << 21);
carry3 = s3 >> 21;
s4 += carry3;
s3 -= carry3 * (1 << 21);
carry3 = s3 >> 21;
s4 += carry3;
s3 -= carry3 * (1 << 21);
int64_t carry3;
carry3 = (s3 + (1 << 20)) >> 21;
s4 += carry3;
s3 -= carry3 * (1 << 21);
carry3 = (s3 + (1 << 20)) >> 21;
s4 += carry3;
s3 -= carry3 * (1 << 21);
carry3 = s3 >> 21;
s4 += carry3;
s3 -= carry3 * (1 << 21);
carry3 = s3 >> 21;
s4 += carry3;
s3 -= carry3 * (1 << 21);
int64_t carry3;
carry3 = h3 + (1 << 24);
h4 += carry3 >> 25;
h3 -= carry3 & kTop39Bits;