[CORE] Refactor XferCRC to make it branchless and to remove winsock dependency #1228
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Perhaps we could go for even fewer branches by using the data size as a template parameter. Most of the call sites use a size that's known at compile-time. |
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Replacing the winsock call is good. Removing the hibit branch also makes sense, because the branch predictor likely does not work well there (50% chance). I would like to see a performance comparison when this works without any remaining logical mismatch. |
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Fixed the logic on validity handling of the leftover bytes. |
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rebased with main, just going to make some other tweaks |
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Tested and tweaked with the switch replacing the second loop, it doesn't mismatch with the golden replays and you would expect it to mismatch pretty quckly if it was going to. |
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Are you seeing any improvements in overall performance? |
I still need to look into performance testing, need to make a game replay under debug, might just do it with some AI since they can really hit different systems hard. |
| val = htonl(val); | ||
| addCRC (val); | ||
| case 3: | ||
| val += (c[2] << (2 * 8)); |
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I overlooked that this would be invalid if data is NULL.
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Maybe add fallthrough to these cases?
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if i do switch(leftover * validData) that should then be caught in the default case.
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tweaked the switch to catch when data is null, so we don't have valid data. |
This PR refactors the XferCRC to make the code branchless and to remove the winsock dependency within it.
There may be minimal performance improvement from this as other factors will need changing in the data being passed to the CRC to further improve the performance.
The winsock dependency has been replaced with the endian compat library instead.