IR: Add 'distinct' MDNodes to bitcode and assembly

Propagate whether `MDNode`s are 'distinct' through the other types of IR
(assembly and bitcode).  This adds the `distinct` keyword to assembly.

Currently, no one actually calls `MDNode::getDistinct()`, so these nodes
only get created for:

  - self-references, which are never uniqued, and
  - nodes whose operands are replaced that hit a uniquing collision.

The concept of distinct nodes is still not quite first-class, since
distinct-ness doesn't yet survive across `MapMetadata()`.

Part of PR22111.

llvm-svn: 225474

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/AsmParser/LLParser.h b/llvm/lib/AsmParser/LLParser.h
index d8d272b500d..f1df5b8e54b 100644
--- a/llvm/lib/AsmParser/LLParser.h
+++ b/llvm/lib/AsmParser/LLParser.h
@@ -389,7 +389,7 @@ namespace llvm {
     bool ParseMetadataAsValue(Value *&V, PerFunctionState &PFS);
     bool ParseValueAsMetadata(Metadata *&MD, PerFunctionState *PFS);
     bool ParseMetadata(Metadata *&MD, PerFunctionState *PFS);
-    bool ParseMDNode(MDNode *&MD);
+    bool ParseMDNode(MDNode *&MD, bool IsDistinct = false);
     bool ParseMDNodeVector(SmallVectorImpl<Metadata *> &MDs);
     bool ParseInstructionMetadata(Instruction *Inst, PerFunctionState *PFS);