constant_time_msb
mask &= constant_time_msb(j - a->top);
failure = ~constant_time_is_zero_s(constant_time_msb(retval)
err_clear_last_constant_time(1 & ~constant_time_msb(r));
ret = constant_time_select_int(constant_time_msb(ret), ret, 1);
return constant_time_msb(a ^ ((a ^ b) | ((a - b) ^ b)));
return constant_time_msb(~a & (a - 1));
static ossl_inline unsigned int constant_time_msb(unsigned int a);
ret = constant_time_select_int(constant_time_msb(ret), 0, 1);