Generate inline class equality test for Class.isAssignableFrom on Z

adds class equality check as first check; calls C Helper in OOL section on fail Signed-off-by: Matthew Hall <[email protected]>
eclipse-openj9 · Dec 10, 2024 · 81d885e · 81d885e
1 parent 9725406
commit 81d885e
Showing 1 changed file with 18 additions and 11 deletions.
diff --git a/runtime/compiler/z/codegen/J9TreeEvaluator.cpp b/runtime/compiler/z/codegen/J9TreeEvaluator.cpp
@@ -11633,8 +11633,6 @@ J9::Z::TreeEvaluator::VMarrayCheckEvaluator(TR::Node *node, TR::CodeGenerator *c
    return 0;
    }
 
-
-
 /////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////////
 static bool inlineIsAssignableFrom(TR::Node *node, TR::CodeGenerator *cg)
@@ -11789,23 +11787,24 @@ static bool inlineIsAssignableFrom(TR::Node *node, TR::CodeGenerator *cg)
 
 TR::Register *J9::Z::TreeEvaluator::inlineCheckAssignableFromEvaluator(TR::Node *node, TR::CodeGenerator *cg)
    {
-   TR::Register *thisClassReg = cg->evaluate(node->getFirstChild());
-   TR::Register *checkClassReg = cg->evaluate(node->getSecondChild());
+   TR::Register *fromClassReg = cg->evaluate(node->getFirstChild());
+   TR::Register *toClassReg = cg->evaluate(node->getSecondChild());
 
    TR::Register *resultReg = cg->allocateRegister();
    TR::LabelSymbol *helperCallLabel = generateLabelSymbol(cg);
    TR::LabelSymbol *doneLabel = generateLabelSymbol(cg);
+   TR::LabelSymbol *successLabel = generateLabelSymbol(cg);
 
-   TR::RegisterDependencyConditions* deps = new (cg->trHeapMemory()) TR::RegisterDependencyConditions(0, 3, cg);
-   deps->addPostCondition(thisClassReg, TR::RealRegister::AssignAny);
-   deps->addPostConditionIfNotAlreadyInserted(checkClassReg, TR::RealRegister::AssignAny);
-   deps->addPostCondition(resultReg, TR::RealRegister::AssignAny);
+   TR::LabelSymbol* cFlowRegionStart = generateLabelSymbol(cg);
+   generateS390LabelInstruction(cg, TR::InstOpCode::label, node, cFlowRegionStart);
+   cFlowRegionStart->setStartInternalControlFlow();
+   generateS390CompareAndBranchInstruction(cg, TR::InstOpCode::getCmpRegOpCode(), node, toClassReg, fromClassReg, TR::InstOpCode::COND_BE, successLabel, false, false);
 
    /*
-    * TODO: add inlined tests (classEqualityTest, SuperclassTest, etc)
+    * TODO: add inlined tests (SuperclassTest, cast class cache, etc)
     * Inlined tests will be used when possible, or will jump to the OOL section
     * and perform the tests using the CHelper when not possible
-   */
+    */
 
    generateS390BranchInstruction(cg, TR::InstOpCode::BRC, TR::InstOpCode::COND_BRC, node, helperCallLabel);
    TR_S390OutOfLineCodeSection *outlinedSlowPath = new (cg->trHeapMemory()) TR_S390OutOfLineCodeSection(helperCallLabel, doneLabel, cg);
@@ -11818,9 +11817,17 @@ TR::Register *J9::Z::TreeEvaluator::inlineCheckAssignableFromEvaluator(TR::Node
    generateS390BranchInstruction(cg, TR::InstOpCode::BRC, TR::InstOpCode::COND_BRC, node, doneLabel); // exit OOL section
    outlinedSlowPath->swapInstructionListsWithCompilation();
 
+   generateS390LabelInstruction(cg, TR::InstOpCode::label, node, successLabel, deps);
+   generateRIInstruction(cg, TR::InstOpCode::getLoadHalfWordImmOpCode(), node, resultReg, 1);
+
+   TR::RegisterDependencyConditions* deps = new (cg->trHeapMemory()) TR::RegisterDependencyConditions(0, 3, cg);
+   deps->addPostCondition(fromClassReg, TR::RealRegister::AssignAny);
+   deps->addPostConditionIfNotAlreadyInserted(toClassReg, TR::RealRegister::AssignAny);
+   deps->addPostCondition(resultReg, TR::RealRegister::AssignAny);
+
    generateS390LabelInstruction(cg, TR::InstOpCode::label, node, doneLabel, deps);
+   doneLabel->setEndInternalControlFlow();
    node->setRegister(resultReg);
-
    return resultReg;
    }