[NFC][DebugInfo] Fix Wreturn-type gcc warning

GCC warning:
```
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp: In member function ‘llvm::Expected<long unsigned int> llvm::dwarf::CFIProgram::Instruction::getOperandAsUnsigned(const llvm::dwarf::CFIProgram&, uint32_t) const’:
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp:425:1: warning: control reaches end of non-void function [-Wreturn-type]
  425 | }
      | ^
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp: In member function ‘llvm::Expected<long int> llvm::dwarf::CFIProgram::Instruction::getOperandAsSigned(const llvm::dwarf::CFIProgram&, uint32_t) const’:
/llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp:477:1: warning: control reaches end of non-void function [-Wreturn-type]
  477 | }
      | ^
```

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp
index d95cbb7..3ff1c07 100644 (file)
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugFrame.cpp
@@ -422,6 +422,7 @@ CFIProgram::Instruction::getOperandAsUnsigned(const CFIProgram &CFIP,
     return Operand * CodeAlignmentFactor;
   }
   }
+  llvm_unreachable("invalid operand type");
 }
 
 llvm::Expected<int64_t>
@@ -474,6 +475,7 @@ CFIProgram::Instruction::getOperandAsSigned(const CFIProgram &CFIP,
     return Operand * DataAlignmentFactor;
   }
   }
+  llvm_unreachable("invalid operand type");
 }
 
 Error UnwindTable::parseRows(const CFIProgram &CFIP, UnwindRow &Row,