[clang] [llvm] Disentangle DISubprogram ODR type method uniquing from metadata uniquing (PR #217042)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -2049,35 +2050,49 @@ Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
     }
 
     Metadata *CUorFn = getMDOrNull(Record[12 + OffsetB]);
-    DISubprogram *SP = GET_OR_DISTINCT(
-        DISubprogram,
-        (Context,
-         getDITypeRefOrNull(Record[1]),           // scope
-         getMDString(Record[2]),                  // name
-         getMDString(Record[3]),                  // linkageName
-         getMDOrNull(Record[4]),                  // file
-         Record[5],                               // line
-         getMDOrNull(Record[6]),                  // type
-         Record[7 + OffsetA],                     // scopeLine
-         getDITypeRefOrNull(Record[8 + OffsetA]), // containingType
-         Record[10 + OffsetA],                    // virtualIndex
-         HasThisAdj ? Record[16 + OffsetB] : 0,   // thisAdjustment
-         Flags,                                   // flags
-         SPFlags,                                 // SPFlags
-         HasUnit ? CUorFn : nullptr,              // unit
-         getMDOrNull(Record[13 + OffsetB]),       // templateParams
-         getMDOrNull(Record[14 + OffsetB]),       // declaration
-         getMDOrNull(Record[15 + OffsetB]),       // retainedNodes
-         HasThrownTypes ? getMDOrNull(Record[17 + OffsetB])
-                        : nullptr, // thrownTypes
-         HasAnnotations ? getMDOrNull(Record[18 + OffsetB])
-                        : nullptr, // annotations
-         HasTargetFuncName ? getMDString(Record[19 + OffsetB])
-                           : nullptr, // targetFuncName
-         UsesKeyInstructions));
+
+    DISubprogram *SP = nullptr;
+    bool MaybeODRUnique = Context.isODRUniquingDebugTypes() && !IsDistinct &&
+                          !(SPFlags & DISubprogram::SPFlagDefinition) &&
+                          getMDString(Record[3]);
+    if (MaybeODRUnique)
+      SP = Context.getDebugTypeODRUniquer()->getODRSubprogramDecl(
+          getDITypeRefOrNull(Record[1]), getMDString(Record[3])->getString(),
+          getMDOrNull(Record[6]), getMDOrNull(Record[13 + OffsetB]));
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OCHyams wrote:

Ah, right, yes you're right and it's easy to reproduce... I've fixed it but it's not particularly clean 

https://github.com/llvm/llvm-project/pull/217042