performance tips for computations on an ESP32

damn...it's not my day...

it seemed to work once but now it does no longer.

I'm currently working with the original Espruino:

• after uploading the code into flash, the device hangs itself up
  
• trying to reconnect does not report the board type, regardless of reset or power cycling
  
• after reflashing the firmware (which works), connection over Web Serial works as intended - until I upload my source into flash again
  
  

S.th. seems to be terribly wrong right now...

Amendment: my code works fine - albeit slowly - even after uploading into flash as long as I do not compile - as soon as "compiled" is added, the Espruino hangs itself up, does no longer properly connect via Web Serial and I'll have to reflash the firmware in order to "unbrick" it.

2nd amendment: Neopixel.write(B15,Display); seems to crash compiled code - for whatever reason. If I comment it out, I may upload to flash and the code will run fine (but, of course, it will be useless)

3rd amendment: by "compiling" the actual computations only and moving everything else into an uncompiled function, I was able to avoid the hang ups and the code still runs fast enough - but Neopixel.write(B15,Display); has no effect any more (perhaps, because Display wasn't updated properly by the compiled function)