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Another way to tag instructions...


One more way to do what you want occurred to me...

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....

-- Al

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