[Mlir-commits] [mlir] [MLIR][LLVM] Support Recursive DITypes (PR #80251)

[Tobias Gysi]

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@@ -133,15 +130,26 @@ DebugTranslation::translateImpl(DICompositeTypeAttr attr) {
     isDistinct = true;
   }
 
-  return getDistinctOrUnique<llvm::DICompositeType>(
-      isDistinct, llvmCtx, attr.getTag(), getMDStringOrNull(attr.getName()),
-      translate(attr.getFile()), attr.getLine(), translate(attr.getScope()),
-      translate(attr.getBaseType()), attr.getSizeInBits(),
-      attr.getAlignInBits(),
-      /*OffsetInBits=*/0,
-      /*Flags=*/static_cast<llvm::DINode::DIFlags>(attr.getFlags()),
-      llvm::MDNode::get(llvmCtx, elements),
-      /*RuntimeLang=*/0, /*VTableHolder=*/nullptr);
+  llvm::DICompositeType *placeholder =
+      getDistinctOrUnique<llvm::DICompositeType>(
+          isDistinct, llvmCtx, attr.getTag(), getMDStringOrNull(attr.getName()),
+          translate(attr.getFile()), attr.getLine(), translate(attr.getScope()),
+          translate(attr.getBaseType()), attr.getSizeInBits(),
+          attr.getAlignInBits(),
+          /*OffsetInBits=*/0,
+          /*Flags=*/static_cast<llvm::DINode::DIFlags>(attr.getFlags()),
+          /*Elements=*/nullptr, /*RuntimeLang=*/0, /*VTableHolder=*/nullptr);
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gysit wrote:

I just fixed a problem similar to this today https://github.com/llvm/llvm-project/pull/83257. I wonder if this is problematic here as well and if it would make sense to use:
`  auto dummy = llvm::MDNode::getTemporary(ctx, std::nullopt);`
instead of nullptr here. As metadata nodes are uniqued it could be possible that the later replace step actually replaces the elements of multiple composite types nodes. Although it looks like composite types usually are distinct. I guess that solves the problem... still better safe than sorry.

https://github.com/llvm/llvm-project/pull/80251