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
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 2eb6721..8152799 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -773,7 +773,9 @@
assert(!isa<LocalAsMetadata>(MD) && "Unexpected function-local metadata");
Record.push_back(VE.getMetadataID(MD) + 1);
}
- Stream.EmitRecord(bitc::METADATA_NODE, Record);
+ Stream.EmitRecord(N->isDistinct() ? bitc::METADATA_DISTINCT_NODE
+ : bitc::METADATA_NODE,
+ Record);
Record.clear();
}