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[Henrik Sperre Johansen]

commits-2 wrote
> ARMv8 has an amazingly exotic scheme for encoding bitfields as immediates
> in logical operations.  Copy LLVM's encoder.  So far this is unverified
> because I cannot make sense of 
> 	immN:NOT(imms)
> in
> 		len = HighestSetBit(immN:NOT(imms));
> in DecodeBitMasks on page J1-7389 of the Arm ARM.
> If you can make sense of this either consider fully implementing
> CogARMv8Compiler>>decodeBitMasksN:imms:immr: or explaining to me what is
> meant by "immN:NOT(imms)" (via email to OpenSMalltalk-VM ?).
> 
> AdvThanksance.

Is line 91 of
https://github.com/NationalSecurityAgency/ghidra/blob/master/Ghidra/Processors/AARCH64/src/main/java/DecodeBitMasks.java
of any help?

Iow, 
: -> concatenate bits
NOT -> ... not

Cheers,
Henry




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