[release/6.0-rc2] [interp] Add wide data item index static load and stores #59262
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For methods that require more than 64k data items, add a variant stsfld instruction that stores data item indices as 32-bit integers instead of 16-bit. To solve this problem in general, we need wide variants of more opcodes, but for specific (machine generated) methods, a wide stsfld instruction is sufficient. Resolves https://devdiv.visualstudio.com/DevDiv/_workitems/edit/1398069
Use stackval_from_data and stackval_to_data instead of memcpy. Don't duplicate code get_data_item_wide_index. Only use the wide opcodes if any of the data item indices of a given instruction need it, not just when the method total number of indices overflows.
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Tagging subscribers to this area: @BrzVlad Issue DetailsBackport of #59220 to release/6.0-rc2 /cc @lambdageek Customer ImpactTestingRisk
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Backport of #59220 to release/6.0-rc2
/cc @lambdageek
Customer Impact
Interpreted .NET 6 Android applications that depend on AndroidX, Maui, SkiaSharp and other frameworks crash at startup.
When a project references some of these frameworks, the build process generates a method that initializes C# fields corresponding to Android resources. This method can be very large and it can initialize on the order of ~100k fields. This stresses a limit in the interpreter on the number of data items that a single method can mention.
Testing
CI and manual testing.
Risk
Low.
The issue does not arise in the mono JIT or in AOT. While developers would lose out on the ability to use hot reload with their code, disabling the interpreter is a viable workaround.
The fix adds a new interpreter opcode that raises the limit on the number of data items that can be referenced from 64k to 4 billion. The fix is tailored to the particular generated UpdateIdValues method from .NET 6 Android. It does not address more general limitations of interpreting large method bodies.