IR: Allow multiple global metadata attachments with the same type.
This will be necessary to allow the global merge pass to attach
multiple debug info metadata nodes to global variables once we reverse
the edge from DIGlobalVariable to GlobalVariable.
Differential Revision: http://reviews.llvm.org/D20414
llvm-svn: 271358
diff --git a/llvm/lib/IR/LLVMContextImpl.h b/llvm/lib/IR/LLVMContextImpl.h
index 02af08a..3e0ba4a 100644
--- a/llvm/lib/IR/LLVMContextImpl.h
+++ b/llvm/lib/IR/LLVMContextImpl.h
@@ -997,6 +997,33 @@
}
};
+/// Multimap-like storage for metadata attachments for globals. This differs
+/// from MDAttachmentMap in that it allows multiple attachments per metadata
+/// kind.
+class MDGlobalAttachmentMap {
+ struct Attachment {
+ unsigned MDKind;
+ TrackingMDNodeRef Node;
+ };
+ SmallVector<Attachment, 1> Attachments;
+
+public:
+ bool empty() const { return Attachments.empty(); }
+
+ /// Appends all attachments with the given ID to \c Result in insertion order.
+ /// If the global has no attachments with the given ID, or if ID is invalid,
+ /// leaves Result unchanged.
+ void get(unsigned ID, SmallVectorImpl<MDNode *> &Result);
+
+ void insert(unsigned ID, MDNode &MD);
+ void erase(unsigned ID);
+
+ /// Appends all attachments for the global to \c Result, sorting by attachment
+ /// ID. Attachments with the same ID appear in insertion order. This function
+ /// does \em not clear \c Result.
+ void getAll(SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const;
+};
+
class LLVMContextImpl {
public:
/// OwnedModules - The set of modules instantiated in this context, and which
@@ -1108,7 +1135,7 @@
DenseMap<const Instruction *, MDAttachmentMap> InstructionMetadata;
/// Collection of per-GlobalObject metadata used in this context.
- DenseMap<const GlobalObject *, MDAttachmentMap> GlobalObjectMetadata;
+ DenseMap<const GlobalObject *, MDGlobalAttachmentMap> GlobalObjectMetadata;
/// DiscriminatorTable - This table maps file:line locations to an
/// integer representing the next DWARF path discriminator to assign to