[LLVMdev] [RFC] Extending MachineInstr.Flags

[Jakob Stoklund Olesen]

On Jan 3, 2012, at 7:18 AM, girish gulawani wrote:

> This is purely from a particular VLIW target back-end perspective. There it is possible to schedule an MI on to one of multiple execution pipes. This leads to a different instruction encoding per the pipe it is bound to, and need to percolate this information down.
> Would it be advisable to extend and use the "MachineInstr.Flags" field for this purpose?

No, the MachineInstr objects need to stay as small as possible.

For something like this, I would suggest that you add an immediate operand to the relevant instructions. That gives you 64 bits of flags you can use any way you like.

/jakob

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