JitArm64: Implement accurate NaNs #11321
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For quite some time now, we've had a setting on x86-64 that makes Dolphin handle NaNs in a more accurate but slower way. There's only one game that cares about this, Dragon Ball: Revenge of King Piccolo, and what that game cares about more specifically is that the default NaN (or "generated NaN" as I believe it's called in PowerPC documentation) is the same as on PowerPC. On ARM, the default NaN is the same as on PowerPC, so for the longest time we didn't need to do anything special to get Dragon Ball: Revenge of King Piccolo working. However, in 93e636a I changed how we handle FMA instructions in a way that resulted in the sign of NaNs becoming inverted for nmadd/nmsub instructions, breaking the game. To fix this, let's implement the AccurateNaNs setting, like on x86-64.
lioncash
approved these changes
Dec 7, 2022
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For quite some time now, we've had a setting on x86-64 that makes Dolphin handle NaNs in a more accurate but slower way. There's only one game that cares about this, Dragon Ball: Revenge of King Piccolo, and what that game cares about more specifically is that the default NaN (or "generated NaN" as I believe it's called in PowerPC documentation) is the same as on PowerPC. On ARM, the default NaN is the same as on PowerPC, so for the longest time we didn't need to do anything special to get Dragon Ball: Revenge of King Piccolo working. However, in 93e636a I changed how we handle FMA instructions in a way that resulted in the sign of NaNs becoming inverted for nmadd/nmsub instructions, breaking the game. To fix this, let's implement the AccurateNaNs setting, like on x86-64.