LLVM 14.0: Support btf_tag-related annotations in metadata types

[RyanGlScott]

LLVM 14.0 adds an additional annotations field to the following pieces of metadata in service of supporting the new btf_tag attribute:

• METADATA_DERIVED_TYPE: llvm/llvm-project@430e223
• METADATA_COMPOSITE_TYPE: llvm/llvm-project@0b32dca
• METADATA_SUBPROGRAM: llvm/llvm-project@d383df3
• METADATA_GLOBAL_VAR: llvm/llvm-project@30c2884
• METADATA_LOCAL_VAR: llvm/llvm-project@1bebc31

As these are pretty common, most programs compiled with -g using Clang 14.0.0 will contain them. Here is one such example:

int main(int argc, char *argv[]) {
  return 0;
}

When compiled with clang test.c -c -emit-llvm -g with Clang 14.0.0, llvm-pretty-bc-parser will be unable to handle it:

λ> parseBitCodeFromFile  "../../C/test.bc"
Left (Error {errContext = ["METADATA_DERIVED_TYPE","METADATA_BLOCK","@main","FUNCTION_BLOCK","FUNCTION_BLOCK_ID","value symbol table","MODULE_BLOCK","Bitstream"], errMessage = "Invalid record size: 14\nExpected size between 12 and 13\nAre you sure you're using a supported version of LLVM/Clang?\nCheck here: https://github.com/GaloisInc/llvm-pretty-bc-parser\n"})