Revert "[DebugInfo] Enforce implicit constraints on `distinct` MDNodes"

This reverts commit 8cd35ad854ab4458fd509447359066ea3578b494.

It breaks `TestMembersAndLocalsWithSameName.py` on GreenDragon and
Mikael Holmén points out in D104827 that bitcode files created with the
patch cannot be parsed with binaries built before it.

1 files changed, 2 insertions, 8 deletions

diff --git a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
index a2ad4a4..8493eb7 100644
--- a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
+++ b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
@@ -555,7 +555,7 @@ class MetadataLoader::MetadataLoaderImpl {
   }
 
   /// Upgrade the expression from previous versions.
-  Error upgradeDIExpression(uint64_t FromVersion, bool &IsDistinct,
+  Error upgradeDIExpression(uint64_t FromVersion,
                             MutableArrayRef<uint64_t> &Expr,
                             SmallVectorImpl<uint64_t> &Buffer) {
     auto N = Expr.size();
@@ -629,9 +629,6 @@ class MetadataLoader::MetadataLoaderImpl {
       LLVM_FALLTHROUGH;
     }
     case 3:
-      IsDistinct = false;
-      LLVM_FALLTHROUGH;
-    case 4:
       // Up-to-date!
       break;
     }
@@ -1984,12 +1981,9 @@ Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
     auto Elts = MutableArrayRef<uint64_t>(Record).slice(1);
 
     SmallVector<uint64_t, 6> Buffer;
-    if (Error Err = upgradeDIExpression(Version, IsDistinct, Elts, Buffer))
+    if (Error Err = upgradeDIExpression(Version, Elts, Buffer))
       return Err;
 
-    if (IsDistinct)
-      return error("Invalid record");
-
     MetadataList.assignValue(
         GET_OR_DISTINCT(DIExpression, (Context, Elts)), NextMetadataNo);
     NextMetadataNo++;