PHP: Is there a way to remove line returns and spaces from the output file?

[Nuxly Stardust]

I would like to make my page load faster by removing line returns and consecutive spaces from the generated files.
Is there any way to make a script that does it in realtime or should I edit all my files and re-upload them?

Thanks
It would make the pages smaller, my web editor replaces tabs with spaces in the code.
but how do I use the regular expressions on the output? it is generated from multiple php and html files, I don't have the whole page in a variable.