FCOMI fails to clear OF, SF, AF - #5809
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Looks like all three of the ARMv8.4 runners decided to off themselves simultaneously for some reason today. That'll stall out all PRs for the day until I can figure out what happened there. |
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For FCOMI/FCOMIP/FUCOMI/FUCOMIP: the Intel SDM states these instructions "set OF, SF, and AF to 0" regardless of the comparison result.
The AMD manual doesn't mention OF/SF/AF for these instructions at all.
Testing on real hardware (at least 3 AMD systems) confirms OF, SF, and AF are unconditionally cleared to 0 after these instructions, regardless of their prior value.
This PR makes it such that the affected instructions always clear OF, SF and AF to zero.