[cfe-commits] MS name mangling improvements

[Richard Smith]

On Mon, Jun 18, 2012 at 2:28 AM, João Matos <ripzonetriton at gmail.com> wrote:
> Attached patch with some improvements to the Microsoft mangling:
>
>    - R-value references mangling
>    - Back references (done by Timur Iskhodzhanov)
>    - nullptr mangling

Comments inline below.

> --- lib/AST/MicrosoftMangle.cpp	(revision 158591)
> +++ lib/AST/MicrosoftMangle.cpp	(working copy)
> @@ -31,6 +31,9 @@
>    MangleContext &Context;
>    raw_ostream &Out;
>
> +  typedef llvm::DenseMap<const IdentifierInfo*, unsigned> BackRefMap;
> +  BackRefMap back_references;

Per the coding conventions, this should be named BackReferences (and
likewise for other variable and field declarations in the patch).

> +
>    ASTContext &getASTContext() const { return Context.getASTContext(); }
>
>  public:
> @@ -641,7 +644,14 @@
>
>  void MicrosoftCXXNameMangler::mangleSourceName(const IdentifierInfo *II) {
>    // <source name> ::= <identifier> @
> -  Out << II->getName() << '@';
> +  BackRefMap::iterator found = back_references.find(II);
> +  if (found == back_references.end()) {
> +    Out << II->getName() << '@';
> +    if (back_references.size() < 10)
> +      back_references[II] = back_references.size();  // size++

This will do different things depending on the order in which the
arguments to operator= are evaluated.


> @@ -998,17 +1010,28 @@
>    if (Proto->getNumArgs() == 0 && !Proto->isVariadic()) {
>      Out << 'X';
>    } else {
> +    typedef llvm::DenseMap<void*, unsigned> BackRef;
> +    BackRef back_refs;
>      if (D) {
>        // If we got a decl, use the type-as-written to make sure arrays
>        // get mangled right.  Note that we can't rely on the TSI
>        // existing if (for example) the parameter was synthesized.
>        for (FunctionDecl::param_const_iterator Parm = D->param_begin(),
>               ParmEnd = D->param_end(); Parm != ParmEnd; ++Parm) {
> -        if (TypeSourceInfo *typeAsWritten = (*Parm)->getTypeSourceInfo())
> -          mangleType(typeAsWritten->getType(),
> -                     typeAsWritten->getTypeLoc().getSourceRange());
> -        else
> -          mangleType((*Parm)->getType(), SourceRange());
> +        TypeSourceInfo *typeAsWritten = (*Parm)->getTypeSourceInfo();
> +        QualType type = typeAsWritten ? typeAsWritten->getType() : (*Parm)->getType();
> +        CanQualType canonical = getASTContext().getCanonicalType(type);
> +        void *type_ptr = canonical.getAsOpaquePtr();
> +        BackRef::iterator found = back_refs.find(type_ptr);
> +        if (found == back_refs.end()) {
> +          SourceRange SR = typeAsWritten ? typeAsWritten->getTypeLoc().getSourceRange()
> +              : (*Parm)->getSourceRange();
> +          mangleType(type, SR);
> +          if (back_refs.size() < 10 && canonical->getTypeClass() != Type::Builtin)
> +            back_refs[type_ptr] = back_refs.size();  // size++
> +        } else {
> +          Out << found->second;
> +        }

It looks like this will include cv-qualifiers on function parameter
types in the mangled name. That can't be right, since they're not part
of the function type. I suspect you should drop the uses of
getTypeSourceInfo() here. (This bug seems to predate your change).

> +++ test/CodeGenCXX/mangle-ms-cpp11.cpp	(working copy)

We use 'cxx11' not 'cpp11' in the tests/ area to refer to C++11.