Is it possible that the guid of the uasset remains the same if I modify a file?

Recently I ran into a problem with the patch, I found that after twice cooking, the file which I didn‘t modify generate different .uexp files, causing the patch to be too large. But there is only its .uexp and no .uasset in the patch. So I would like to ask if it is possible to confirm that this file has not been modified by judging that .uasset’s guid has not changed. If so, from which part of the source code can I find this answer.

Thanks in advance!