Incorrect floating point comparisons involving NaN about dora HOT 2 CLOSED

Oh yes, thanks for spotting that 👍 When implementing that I was too lazy to check that... I will look into that and fix it..

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Hi @dinfuehr,

I think the issue is that CondCode does not have a value to express an "unordered" condition, so it can't check for [ZF=1, PF=1, CF=1]¹, making it look like "less than" [ZF = 0, PF = 0, CF=1] (which is the symptom I saw in the test case)

Looking at the setcc listing it also seems like there is no ready-made instruction for this, so it seems it is not as easy as adding just another branch/magic number to https://github.com/dinfuehr/dora/blob/master/src/cpu/x64/asm.rs#L805. :-/

Hope this helps!

¹ https://c9x.me/x86/html/file_module_x86_id_316.html

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