[PATCH] D65347: [RISCV] Fix uninitialized variable after call to evaluateConstantImm

[Francis Visoiu Mistrih via Phabricator via llvm-commits]

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For `llvm/test/MC/RISCV/rv64i-aliases-invalid.s`, UBSan reports:

  lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp:371:9: runtime error: load of value 3879186881, which is not a valid value for type 'RISCVMCExpr::VariantKind'
   SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp:371:9 in

It turns out that evaluateConstantImm does not set `VK` and it remains unitialized when doing comparisons in `isImmXLenLI()`.


https://reviews.llvm.org/D65347

Files:
  llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp

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