if (outputByteEnd > Integer.MAX_VALUE) {
// overflow check
throw runtime.newArgumentError("output offset + bytesize too big");
}
outBytes.ensure((int)outputByteEnd);
inPtr.p = inBytes.getBegin();
outPtr.p = outBytes.getBegin() + outputByteoffset;
int os = outPtr.p + outputBytesize;
EConvResult res = ec.convert(inBytes.getUnsafeBytes(), inPtr, inBytes.getRealSize() + inPtr.p, outBytes.getUnsafeBytes(), outPtr, os, flags);