Implement FRMIDX pseudo instruction

[dylanmckay]

The instruction is supposed to be lower into an movw + adiw.

See AVRInstrInfo.td for more info.

[agnat]

I believe this is already handled here.

Maybe we should close the ... pseudo issues. Not that some helpful nerd starts working on them like I did with the asm-parser tickets...

[dylanmckay]

I opened these up without properly investigating them. I'll have a proper look now.

Not that some helpful nerd starts working on them like I did with the asm-parser tickets

That would be convenient ;)

[dylanmckay]

I closed this one but left the following three open.

• Implement STDWSPQRr pseudo expansion #115 is stopping us from compiling Arduino
• Implement wide load program memory pseudo instructions #112 and Implement wide bit rotate pseudo instructions #113 will cause confusing errors when hit