Merge pull request #10119 from Leonardo2718/fixacmp

Duplicate PassThrough nodes when creating acmp fastpaths
eclipse-openj9 · Jul 13, 2020 · 497e3cb · 497e3cb
2 parents a475ea5 + ad1604a
commit 497e3cb
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/runtime/compiler/codegen/J9CodeGenerator.cpp b/runtime/compiler/codegen/J9CodeGenerator.cpp
@@ -291,6 +291,15 @@ J9::CodeGenerator::fastpathAcmpHelper(TR::Node *node, TR::TreeTop *tt, const boo
             TR::Node* temp = expectedDeps->getChild(i);
             if (temp->getGlobalRegisterNumber() == depNode->getGlobalRegisterNumber())
                continue;
+            else if (temp->getOpCodeValue() == TR::PassThrough)
+               {
+               // PassThrough nodes cannot be commoned because doing so does not
+               // actually anchor the child, causing it's lifetime to not be extended
+               TR::Node* original = temp;
+               temp = TR::Node::create(original, TR::PassThrough, 1, original->getFirstChild());
+               temp->setLowGlobalRegisterNumber(original->getLowGlobalRegisterNumber());
+               temp->setHighGlobalRegisterNumber(original->getHighGlobalRegisterNumber());
+               }
             glRegDeps->addChildren(&temp, 1);
             }
          }