[llvm] r234200 - DebugInfo: Add MDTypeRefArray, to replace DITypeArray

[Duncan P. N. Exon Smith]

> On 2015-Apr-06, at 12:58, David Blaikie <dblaikie at gmail.com> wrote:
> 
> 
> 
> On Mon, Apr 6, 2015 at 12:48 PM, Duncan P. N. Exon Smith <dexonsmith at apple.com> wrote:
> Author: dexonsmith
> Date: Mon Apr  6 14:48:50 2015
> New Revision: 234200
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=234200&view=rev
> Log:
> DebugInfo: Add MDTypeRefArray, to replace DITypeArray
> 
> This array-like wrapper adapts `MDTuple` to have elements of `MDTypeRef`
> (whereas `MDTypeArray` has elements of `MDType`).  This is necessary to
> migrate code using `DITypeArray`.  The only use of this is
> `MDSubroutineType`'s `getTypeArray()` accessor.
> 
> Modified:
>     llvm/trunk/include/llvm/IR/DebugInfoMetadata.h
> 
> Modified: llvm/trunk/include/llvm/IR/DebugInfoMetadata.h
> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/DebugInfoMetadata.h?rev=234200&r1=234199&r2=234200&view=diff
> ==============================================================================
> --- llvm/trunk/include/llvm/IR/DebugInfoMetadata.h (original)
> +++ llvm/trunk/include/llvm/IR/DebugInfoMetadata.h Mon Apr  6 14:48:50 2015
> @@ -89,6 +89,42 @@ typedef TypedDebugNodeRef<DebugNode> Deb
>  typedef TypedDebugNodeRef<MDScope> MDScopeRef;
>  typedef TypedDebugNodeRef<MDType> MDTypeRef;
> 
> +class MDTypeRefArray {
> +  const MDTuple *N = nullptr;
> +
> +public:
> +  MDTypeRefArray(const MDTuple *N) : N(N) {}
> +  operator MDTuple *() const { return const_cast<MDTuple *>(N); }
> +  MDTuple *operator->() const { return const_cast<MDTuple *>(N); }
> +  MDTuple &operator*() const { return *const_cast<MDTuple *>(N); }
> +
> +  unsigned size() const { return N->getNumOperands(); }
> +  MDTypeRef operator[](unsigned I) const { return MDTypeRef(N->getOperand(I)); }
> +
> +  class iterator : std::iterator<std::input_iterator_tag, MDTypeRef,
> +                                 std::ptrdiff_t, void, MDTypeRef> {
> +    MDNode::op_iterator I;
> +
> +  public:
> +    explicit iterator(MDNode::op_iterator I) : I(I) {}
> +    MDTypeRef operator*() const { return MDTypeRef(*I); }
> +    iterator &operator++() {
> +      ++I;
> +      return *this;
> +    }
> +    iterator operator++(int) {
> +      iterator Temp(*this);
> +      ++I;
> +      return Temp;
> +    }
> +    bool operator==(const iterator &X) const { return I == X.I; }
> +    bool operator!=(const iterator &X) const { return I != X.I; }
> 
> FWIW, ideally op overloads that can be non-members should be (to allow the same conversions on the LHS and RHS) - these could be inline friend definitions (or one a friend, and one not - since it can be defined in terms of the other). Not a big deal & we violate this all over the place, and it's not immediately apparent that any conversions should be possible on either side - just good habits.

I'll keep that in mind.  Here there are no implicit conversions, so I'm
tempted to leave it as is (since this is the most compact/clear way of
writing the code).

Unless you think this should *always* be the way we do it?  If so, you
might propose an addition to the coding standards.  FWIW, I don't have
a strong opinion one way or the other; happy to switch to "the one true
way" if we decide there is one.

>  
> +  };
> +
> +  iterator begin() const { return iterator(N->op_begin()); }
> +  iterator end() const { return iterator(N->op_end()); }
> +};
> +
>  /// \brief Tagged DWARF-like metadata node.
>  ///
>  /// A metadata node with a DWARF tag (i.e., a constant named \c DW_TAG_*,
> @@ -826,7 +862,7 @@ public:
> 
>    TempMDSubroutineType clone() const { return cloneImpl(); }
> 
> -  MDTuple *getTypeArray() const { return getElements(); }
> +  MDTypeRefArray getTypeArray() const { return getElements(); }
>    Metadata *getRawTypeArray() const { return getRawElements(); }
> 
>    static bool classof(const Metadata *MD) {
> 
> 
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits