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Re: sched2, ret, use, and VLIW bundling
> The problem may be in the dependency cost between the SET (insn 27)
> and the USE (insn 30) being >= 1. Have you tried using
> targetm.sched.adjust_cost() hook to set the cost of USE to 0?
It doesn't get called for those two insns.
> Anyway, this seems strange, the scheduler should just output the
> USEs as soon as they are ready.
It does - that's the problem. The SET is setting the register that
the USE is using, so the scheduler won't pack them together.
I want to disable that, since *I* know that the USE is only there to
keep the return value from being optimized away; the value isn't an
actual dependency *there*.