Should there be a space before or after a break (or none)?

For a search engine or screen reader to read text should there be a space before or after a <br> break (or none at all)? If there isn't are they clever enough to insert a space - and not join the word before and after the <br> together?

1. Space is before

   <h1>First bit of heading <br>rest of heading</h1>
   

2. Space is after

   <h1>First bit of heading<br> rest of heading</h1>
   

3. No space. Will this get read as "First bit of headingrest of heading"?

   <h1>First bit of heading<br>rest of heading</h1>