[ARM64] Fix lifting of mrs xzr, ... to not reference the xzr register#7220
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plafosse
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Aug 5, 2025
ARM64 lifting replaces references to the zero register with constant zeroes. The zero register is not intended to appear in any lifted IL. In the case of the `mrs` instruction, the destination being a zero register means the system register is accessed only for a side-effect, and is not stored anywhere. The lifting is updated to specify no output registers for the intrinsic in that case.
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ARM64 lifting replaces references to the zero register with constant zeroes. The zero register is not intended to appear in any lifted IL.
In the case of the
mrsinstruction, the destination being a zero register means the system register is accessed only for a side-effect, and is not stored anywhere. The lifting is updated to specify no output registers for the intrinsic in that case.