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AArch64 NCG can use invalid immediates
GHC tries to pass 0xFFFFFFFFFFFFFFFF as an immediate to `orr`, resulting in the following error: ``` Error: immediate out of range at operand 3 -- `orr w15,w0,#18446744073709551615' ``` NB: 18446744073709551615 = 0xFFFFFFFFFFFFFFFF. This was discovered using `test-primops`, see [this pipeline](https://gitlab.haskell.org/ghc/test-primops/-/jobs/2573041#L309). I don't have a concrete reproducer to provide right now but it should be pretty straightforward to produce one.
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