[PATCH] D44336: Implement --cref.

[Rafael Avila de Espindola via llvm-commits]

Rui Ueyama via Phabricator via llvm-commits
<llvm-commits at lists.llvm.org> writes:

> +defm cref: B<"cref",
> +    "Output cross reference table",
> +    "Do not output cross reference table">;
> +

Why B? Is there a --no-cref?

> +// Output a cross reference table to stdout. This is for --cref.
> +//
> +// For each global symbol, we print out a file that defines the symbol
> +// followed by files that uses that symbol. Here is an example.
> +//
> +//     strlen     /lib/x86_64-linux-gnu/libc.so.6
> +//                tools/lld/tools/lld/CMakeFiles/lld.dir/lld.cpp.o
> +//                lib/libLLVMSupport.a(PrettyStackTrace.cpp.o)
> +//
> +// In this case, strlen is defined by libc.so.6 and used by other two
> +// files.
> +void elf::writeCrossReferenceTable() {
> +  if (!Config->Cref)
> +    return;
> +
> +  // Collect symbols and files.
> +  MapVector<Symbol *, SetVector<InputFile *>> Map;
> +  for (InputFile *File : ObjectFiles) {
> +    for (Symbol *B : File->getSymbols()) {

I would probably avoid B since it is a strange choice now that
SymbolBody is gone.

> +      if (auto *Sym = dyn_cast<SharedSymbol>(B))

This can be an isa<>, no?

> +        Map[Sym].insert(File);
> +      if (auto *Sym = dyn_cast<Defined>(B))
> +        if (!Sym->isLocal() || (!Sym->Section || Sym->Section->Live))
> +          Map[Sym].insert(File);
> +    }
> +  }
> +
> +  auto Print = [](StringRef A, StringRef B) {
> +    outs() << left_justify(A, 49) << " " << B << "\n";
> +  };

This doesn't need to be a lambda.

Cheers,
Rafael