Win7 problem + fix

[rwbc]

Win7 problem + fix

[mhonert]

Hi Guenther,

thanks for trying out my chess engine and for providing the Win7 fix!
It seems that the earliest version which supports GetSystemTimePreciseAsFileTime is Windows 8.

I benchmarked several WebAssembly runtimes and WAVM was the fastest.
With the default backend, Wasmer is around 4 times slower than WAVM.
By using the --backend llvm option with Wasmer, performance increases, but is still around 30% slower than WAVM.
I'm not sure how many ELO points this translates to.

But for Windows 7 users the best option right now is to use Wasmer with the "--backend llvm" line, e.g.
wasmer.exe run --backend llvm engine.wasm

For the next release I will add a note for Windows 7 users to the release page.

Best regards,
Martin

[rwbc]

Martin, thanks for the quick answer and for the backend speedup hint :)

[mhonert]

The workaround is now documented in the Wiki and the release page contains a note for Windows 7 users, which links to the Wiki.

If the performance difference between WAVM and Wasmer becomes smaller in the future, I will probably switch out the bundled runtime.