[llvm-debuginfo-analyzer] Fix a couple of unhandled DWARF situations leading to a crash

[jalopezg-git]

This pull request fixes a couple of unhandled situations in DWARF input leading to a crash. Specifically,

• If the DWARF input contains a declaration of a C variadic function (where ... translates to DW_TAG_unspecified_parameters), which is then followed by a definition, llvm_unreachable() is hit in LVScope::addMissingElements().
  This is only visible in Debug builds (see stack trace below), but still. test-dwarf-clang-unspec-params.elf triggers this condition.

Invalid symbol kind.
UNREACHABLE executed at /home/jalopezg/repos/llvm-project/llvm/lib/DebugInfo/LogicalView/Core/LVScope.cpp:345!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: _build/Debug/bin/llvm-debuginfo-analyzer --print=all --attribute=all /tmp/test-dwarf-clang-unspec-params.elf
 #0 0x00005577295666f6 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /home/jalopezg/repos/llvm-project/llvm/lib/Support/Unix/Signals.inc:804:22
 #1 0x0000557729566b09 PrintStackTraceSignalHandler(void*) /home/jalopezg/repos/llvm-project/llvm/lib/Support/Unix/Signals.inc:880:1
 #2 0x0000557729563f1f llvm::sys::RunSignalHandlers() /home/jalopezg/repos/llvm-project/llvm/lib/Support/Signals.cpp:105:20
 #3 0x0000557729565fb4 SignalHandler(int, siginfo_t*, void*) /home/jalopezg/repos/llvm-project/llvm/lib/Support/Unix/Signals.inc:418:13
 #4 0x00007fc5ff23e710 (/usr/lib/libc.so.6+0x3e710)
 #5 0x00007fc5ff28e83c (/usr/lib/libc.so.6+0x8e83c)
 #6 0x00007fc5ff23e668 gsignal (/usr/lib/libc.so.6+0x3e668)
 #7 0x00007fc5ff2264b8 abort (/usr/lib/libc.so.6+0x264b8)
 #8 0x00005577294ad073 bindingsErrorHandler(void*, char const*, bool) /home/jalopezg/repos/llvm-project/llvm/lib/Support/ErrorHandling.cpp:223:55
 #9 0x0000557728f56b0c llvm::logicalview::LVScope::addMissingElements(llvm::logicalview::LVScope*) /home/jalopezg/repos/llvm-project/llvm/lib/DebugInfo/LogicalView/Core/LVScope.cpp:322:5
#10 0x0000557728f5f4b7 llvm::logicalview::LVScopeFunction::resolveReferences() /home/jalopezg/repos/llvm-project/llvm/lib/DebugInfo/LogicalView/Core/LVScope.cpp:1773:9

• Parsing of instructions in LVBinaryReader::createInstructions() does not check whether Offset lies within the Bytes ArrayRef. A specially crafted DWARF input can lead to this condition.

__
NOTE: this PR is a backport of upstream llvm#137221 to the zmpr-b-llvmorg-19.1.1-patches branch. Such branch is forked from upstream tag llvmorg-19.1.1.

FYI @peledins-zimperium.

[jalopezg-git]

Thank you for review 👍; replied to your comments; PTAL.

[peledins-zimperium]

Thanks!