Xtensa Support

[imbillow]

Your checklist for this pull request

• I've documented or updated the documentation of every API function and struct this PR changes.
• I've added tests that prove my fix is effective or that my feature works (if possible)

Detailed description

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Test plan

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Closing issues

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[Rot127]

Please keep in mind the LITBASE mechanic Xtensa has.
No other disassembler seems to support it. So it would be nice if CS gives at least an option to take care of it.
See: https://youtu.be/QMO2vMBcx7Y?feature=shared&t=808

[XVilka]

@imbillow what LLVM version you have used as a base for this PR? Mainstream LLVM 18? Or a fork from developers working on the Xtensa patches?

[imbillow]

@imbillow what LLVM version you have used as a base for this PR? Mainstream LLVM 18? Or a fork from developers working on the Xtensa patches?

I'm using the auto-sync branch of llvm-capstone, I think it's llvm-18, I'm not sure.

commit 5943ec6923d64e63b9645aa230cd9b86bd63a51b (HEAD -> auto-sync, origin/auto-sync, origin/HEAD)
Author: Rot127 <[email protected]>
Date:   Tue Jun 4 03:29:20 2024 -0500

    Add Alpha and LoongArch to the CI tests.

[Rot127]

It is LLVM 18. Please quickly diff the Target/Xtensa directories against each other. If there are vast differences, we can consider merging them earlier.

[Rot127]

@imbillow I fixed some issue while being at it: imbillow#1

Please check this issue here with test_litbase:

ctest --test-dir build --output-on-failure -R integration*
Internal ctest changing into directory: /home/user/repos/capstone/build
Test project /home/user/repos/capstone/build
...
    Start 11: integration_test_litbase
3/3 Test #11: integration_test_litbase .........Subprocess aborted***Exception:   0.16 sec
test_litbase: /home/user/repos/capstone/arch/Xtensa/XtensaInstPrinter.c:131: printL32RTarget: Assertion `(Value >= -262144 && Value <= -4) && "Invalid argument, value must be in ranges [-262144,-4]"' failed.

Also, it is weird. But in the CI it builds Xtensa without my edits. But it shouldn't because those macros don't exist. Or did you add them and I just overlooked them?

[imbillow]

The clang-tidy warnings are a false positive, because SRDecoderTable[i + 1] does not cause the array to go out of bounds if i + 1 < sizeof(SRDecoderTable) is satisfied.

[imbillow]

Auto-Sync/check fix in capstone-engine/llvm-capstone#61

[Rot127]

@kabeor Your turn

[kabeor]

WoW, really cool, thanks!