[llvm] [IR] Improve check for target extension types disallowed in globals. (PR #116639)

[Nikita Popov via llvm-commits]

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@@ -425,6 +441,34 @@ bool StructType::isScalableTy(SmallPtrSetImpl<const Type *> &Visited) const {
   return false;
 }
 
+bool StructType::containsNonGlobalTargetExtType(
+    SmallPtrSetImpl<const Type *> &Visited) const {
+  if ((getSubclassData() & SCDB_ContainsNonGlobalTargetExtType) != 0)
+    return true;
+
+  if ((getSubclassData() & SCDB_NotContainsNonGlobalTargetExtType) != 0)
+    return false;
+
+  if (!Visited.insert(this).second)
+    return false;
+
+  for (Type *Ty : elements()) {
+    if (Ty->containsNonGlobalTargetExtType(Visited)) {
+      const_cast<StructType *>(this)->setSubclassData(
+          getSubclassData() | SCDB_ContainsNonGlobalTargetExtType);
+      return true;
+    }
+  }
+
+  // For structures that are opaque, return false but do not set the
+  // SCDB_NotContainsNonGlobalTargetExtType flag since it may gain non-global
+  // target extension types when it becomes non-opaque.
+  if (!isOpaque())
+    const_cast<StructType *>(this)->setSubclassData(
+        getSubclassData() | SCDB_NotContainsNonGlobalTargetExtType);
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nikic wrote:

I'm sad that our types aren't immutable and we have to do these contortions (https://discourse.llvm.org/t/recursive-types/82707).

https://github.com/llvm/llvm-project/pull/116639