Use baseObj in CardMarking for OffHeap on X

When running with Balanced GC and OffHeap enabled, if the destOwningObject is a dataAddrPointer load, use the baseObj as the owningObjectReg. Signed-off-by: Abdulrahman Alattas <[email protected]>
eclipse-openj9 · Sep 30, 2024 · 5b929a9 · 5b929a9
1 parent 30a47ed
commit 5b929a9
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/runtime/compiler/x/codegen/J9TreeEvaluator.cpp b/runtime/compiler/x/codegen/J9TreeEvaluator.cpp
@@ -10599,7 +10599,13 @@ void J9::X86::TreeEvaluator::VMwrtbarWithoutStoreEvaluator(
    TR::Register *owningObjectReg;
    TR::Register *tempReg = NULL;
 
-   owningObjectReg = cg->evaluate(destOwningObject);
+#if defined(J9VM_GC_ENABLE_SPARSE_HEAP_ALLOCATION)
+   bool stopUsingCopyBaseReg;
+   if (gcMode == gc_modron_wrtbar_cardmark_incremental && TR::Compiler->om.isOffHeapAllocationEnabled() && destOwningObject->isDataAddrPointer())
+      owningObjectReg = cg->evaluate(destOwningObject->getFirstChild());
+   else
+#endif /* defined(J9VM_GC_ENABLE_SPARSE_HEAP_ALLOCATION) */
+      owningObjectReg = cg->evaluate(destOwningObject);
 
    if (doInternalControlFlow)
       {