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Re: [PATCH] Update assertion in sched-ebb.c to cope with table jumps


On Mon, Mar 25, 2019 at 05:12:05PM -0600, Jeff Law wrote:
> To touch on one of the issues I raised.  AFAICT the schedulers don't use
> SCHED_GROUP_P for dealing with tablejumps.  They're used for
> cc0-user/setter, fused insns and the like.  That's a bit of a surprise.
> 
> Given that the table isn't actually associated with the block with the
> tablejump, SCHED_GROUP_P might actually create a whole new set of problems.
> 
> Why oh why is the jump table data not actually attached to the tablejump
> insn itself.  Nearly 30 years of working on GCC and I can't answer that one.

It somewhat makes sense for targets where the jump table is emitted in the
text section; we then need to know its size for jumps over it, etc.


Segher


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