On 3/22/20 2:55 PM, Segher Boessenkool wrote: > Maybe this stuff would be simpler (and more obviously correct) if it > was more explicit CC_REGNUM is a fixed register, and the code would use > it directly everywhere?
Indeed the biggest issue I have in this patch is what CC_MODE to expose from the high-half compare. For unsigned inequality, only the C bit is valid. For signed inequality, only the N + V bits. For equality, only the Z bit. Which I am trying to expose with the multiple creations of CC_REGNUM, which are used within the comparison, which are indeed sanity checked vs the comparison code via %m/%M. But the mode of the CC_REGNUM does not necessarily match up with the mode of the comparison that generates it. And we do not have a CC_NVmode, so I'm using full CCmode for that. This is the part of the patch that could use the most feedback. r~
