[llvm] [DebugInfo] Add DILayerLoc/DILayerLocList and DILocation irlayers operand (PR #215666)

[Alexander Yermolovich via llvm-commits]

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@@ -1482,15 +1486,47 @@ Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
     Metadata *Scope = getMD(Record[3]);
     Metadata *InlinedAt = getMDOrNull(Record[4]);
     bool ImplicitCode = Record.size() >= 6 && Record[5];
-    uint64_t AtomGroup = Record.size() == 8 ? Record[6] : 0;
-    uint8_t AtomRank = Record.size() == 8 ? Record[7] : 0;
+    uint64_t AtomGroup = Record.size() >= 8 ? Record[6] : 0;
+    uint8_t AtomRank = Record.size() >= 8 ? Record[7] : 0;
+    Metadata *IRLayers = Record.size() >= 9 ? getMDOrNull(Record[8]) : nullptr;
     MetadataList.assignValue(
-        GET_OR_DISTINCT(DILocation, (Context, Line, Column, Scope, InlinedAt,
-                                     ImplicitCode, AtomGroup, AtomRank)),
+        GET_OR_DISTINCT(DILocation,
+                        (Context, Line, Column, Scope, InlinedAt, ImplicitCode,
+                         AtomGroup, AtomRank, IRLayers)),
         NextMetadataNo);
     NextMetadataNo++;
     break;
   }
+  case bitc::METADATA_LAYERLOC: {
+    if (Record.size() != 5)
+      return error("Invalid record");
+
+    IsDistinct = Record[0];
+    unsigned Line = Record[1];
+    unsigned Column = Record[2];
+    Metadata *File = getMD(Record[3]);
+    // Read the kind opaquely and let the verifier report a bad type, as the
+    // other DI readers do: an unchecked cast would assert on malformed bitcode.
+    MDString *Kind = dyn_cast_if_present<MDString>(getMD(Record[4]));
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ayermolo wrote:

Not in this case. On writer side I am using:
Record.push_back(VE.getMetadataID(N->getRawKind()));
Which does -1 on write side.
Because Kind is not an optional parameter.
On loader side the getMDString is basically a wrapper aound getMDorNull which does -1 bias. Which not be correct in this case.

https://github.com/llvm/llvm-project/pull/215666