FM'26 Tutorial

[michael-schwarz]

This is the first half of the tutorial for FM'26 and probably as far as we will go for the FOCS version.

This includes:

• An interval analyses treating all globals as top where a local transfer function should be fixed
• Extending this analysis so it uses global store widening

[michael-schwarz]

For the longer session at FM'26 the idea would be to additionally ask for an analysis that detects which global variables are effectively thread-local, i.e., accessed only by one thread (like #1966 and https://github.com/goblint/analyzer/blob/ghosts/src/analyses/phaseGhost.ml) and interact with the gStoreWidening analysis via queries to treat such globals flow-sensitively.

Ideally, we could even distinguish between writes and reads and have both a flow-sensitive treatment within the owner, and a flow-insensitive one for other threads. That would really make it mixed flow-sensitive.