blakepelton 5 hours ago

"Favor the one with lower register pressure" - my mental model says that register pressure is not a property of a single instruction, but rather depends on when successor instructions will be scheduled.

For example, if an instruction defines a value which has 8 uses, then the "register pressure of the instruction" depends on when those 8 uses will be scheduled.

I guess there is a heuristic to compute the register pressure of an instruction based on a guess of when successors will be scheduled?