For PR797:

For PR797:
Make the Bytecode Reader use setjmp/longjump instead of exceptions to handle
errors. The alternative was even uglier than setjmp/longjump as it would
impact the interface and workings of nearly every function in the reader.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29819 91177308-0d34-0410-b5e6-96231b3b80d8