EgorBo / SimdJsonSharp

C# bindings for lemire/simdjson (and full C# port)
Apache License 2.0
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AccessViolations caused by missing padding (SIMDJSON_PADDING with AVX2) #20

Open th3ragex opened 3 years ago

th3ragex commented 3 years ago

Using SimdJsonSharp.Managed nuget with a .Net5 console application in VS19 on Windows 10 with AVX2 support i am able to reproduce an access violation with some Json files.

After a first investigation it looks like the expected padding (SIMDJSON_PADDING) doesn't work. My memory window is showing that there were only very few additional bytes added at the end of my json byte array (probably by debug mode).

grafik The value of 'ptr' was pointing to the selected character shown in the memory window / see 'Autos' window bottom left.

The shown decompiled line seems to correspond to: https://github.com/EgorBo/SimdJsonSharp/blob/0786341a50919f33c2a86a47d4a1848713c9d60e/src/FullyManagedImpl/Utils/stringparsing.cs#L108

If it helps i can share the source code and json .

Workaround: Adding the padding of 32 bytes and the end of the input byte array solved this issue.