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Re: Another way to tag instructions...


Alan 

> Add a new define_insn that uses an UNSPEC (so it can't match anything
> by accident. insert the UNSPEC insns into the instruction stream to
> mark the end of a VLIW schedule group.
> 
> This requires NO modification to shared GCC source (all the changes
> are in your target.md and target.c files) but does depend on either
> "look-ahead" (the emitter for the last real instruction has to look
> forward to see if there's a VLIW-barrier immediately following) or on
> whatever semantics you need to indicate the end of a compacted
> instruction being simple enough....

Thanks. How do I insert an instruction into the stream from the DFA
scheduler component, such as SCHED_VARIABLE_ISSUE? 

Dan.

=============================================================================
Daniel Towner
picoChip Designs Ltd., Riverside Buildings, 108, Walcot Street, BATH,
BA1 5BG
dant@picochip.com
07786 702589


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