[aarch64] Disassemble and lift FEAT_CPA instructions - #8543
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`FEAT_CPA` (Checked Pointer Arithmetic) adds pointer arithmetic instructions that, on overflow out of the address bits, force bit 54 to disagree with bit 55. This makes the result non-canonical so it faults when dereferenced. For readable decompilation these are lifted as if the instructions are supported but enforcement is disabled (i.e., as if the CPU supports `FEAT_CPA` but not `FEAT_CPA2`).
saagarjha
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Checked against kernelcache.release.mac18g and these instructions seem to be lifted now as described
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FEAT_CPA(Checked Pointer Arithmetic) adds pointer arithmetic instructions that, on overflow out of the address bits, force bit 54 to disagree with bit 55. This makes the result non-canonical so it faults when dereferenced.For readable decompilation these are lifted as if the instructions are supported but enforcement is disabled (i.e., as if the CPU supports
FEAT_CPAbut notFEAT_CPA2).