Examples with J9ROMClassPointer com.ibm.j9ddr.vm29.pointer.generated.J9ROMClassPointer used on opensource projects

Example 46 with J9ROMClassPointer

use of com.ibm.j9ddr.vm29.pointer.generated.J9ROMClassPointer in project openj9 by eclipse.

the class CheckEngine method checkClassStatics.

private int checkClassStatics(J9ClassPointer clazz) {
    int result = J9MODRON_GCCHK_RC_OK;
    try {
        boolean validationRequired = true;
        if (J9ClassHelper.isSwappedOut(clazz)) {
            /* if class has been hot swapped (J9AccClassHotSwappedOut bit is set) in Fast HCR,
				 * the ramStatics of the existing class may be reused.  The J9ClassReusedStatics
				 * bit in J9Class->extendedClassFlags will be set if that's the case.
				 * In Extended HCR mode ramStatics might be not NULL and must be valid
				 * NOTE: If class is hot swapped and the value in ramStatics is NULL it is valid 
				 * to have the correspondent ROM Class value in objectStaticCount field greater then 0
				 */
            if (J9ClassHelper.isArrayClass(clazz)) {
                /* j9arrayclass should not be hot swapped */
                result = J9MODRON_GCCHK_RC_CLASS_HOT_SWAPPED_FOR_ARRAY;
                CheckError error = new CheckError(clazz, _cycle, _currentCheck, "Class ", result, _cycle.nextErrorCount());
                _reporter.report(error);
                return result;
            }
            if (J9ClassHelper.areExtensionsEnabled()) {
                /* This is Extended HSR mode so hot swapped class might have NULL in ramStatics field */
                if (clazz.ramStatics().isNull()) {
                    validationRequired = false;
                }
            }
            try {
                /* This case can also occur when running -Xint with extensions enabled */
                if (J9ClassHelper.extendedClassFlags(clazz).allBitsIn(J9JavaClassFlags.J9ClassReusedStatics)) {
                    validationRequired = false;
                }
            } catch (NoSuchFieldError e) {
            /* Flag must be missing from the core. */
            }
        }
        if (validationRequired) {
            // J9ClassLoaderPointer classLoader = clazz.classLoader();
            J9ROMClassPointer romClazz = clazz.romClass();
            UDATA numberOfReferences = new UDATA(0);
            PointerPointer sectionStart = PointerPointer.NULL;
            PointerPointer sectionEnd = PointerPointer.NULL;
            /*
				 * Note: we have no special recognition for J9ArrayClass here
				 * J9ArrayClass does not have a ramStatics field but something else at this place
				 * so direct check (NULL != clazz->ramStatics) would not be correct,
				 * however romClazz->objectStaticCount must be 0 for this case
				 */
            if (!romClazz.objectStaticCount().eq(0)) {
                sectionStart = PointerPointer.cast(clazz.ramStatics());
                sectionEnd = sectionStart.add(romClazz.objectStaticCount());
            }
            /* Iterate all fields of ROM Class looking to statics fields pointed to java objects */
            Iterator<J9ObjectFieldOffset> objectFieldOffsetIterator = J9ObjectFieldOffsetIterator.J9ObjectFieldOffsetIteratorFor(clazz, J9ClassHelper.superclass(clazz), new U32(J9VM_FIELD_OFFSET_WALK_INCLUDE_STATIC | J9VM_FIELD_OFFSET_WALK_ONLY_OBJECT_SLOTS));
            while (objectFieldOffsetIterator.hasNext()) {
                J9ObjectFieldOffset fieldOffset = objectFieldOffsetIterator.next();
                // J9ROMFieldShapePointer field = fieldOffset.getField();
                numberOfReferences = numberOfReferences.add(1);
                /* get address of next field */
                PointerPointer address = sectionStart.addOffset(fieldOffset.getOffsetOrAddress());
                /* an address must be in gc scan range */
                if (!(address.gte(sectionStart) && address.lt(sectionEnd))) {
                    result = J9MODRON_GCCHK_RC_CLASS_STATICS_REFERENCE_IS_NOT_IN_SCANNING_RANGE;
                    CheckError error = new CheckError(clazz, address, _cycle, _currentCheck, "Class ", result, _cycle.nextErrorCount());
                    _reporter.report(error);
                }
            /* check only if we have an object */
            // TODO kmt : can't easily implement this part of the check
            // J9Class* classToCast = vm->internalVMFunctions->internalFindClassUTF8(currentThread, toSearchString, toSearchLength, classLoader, J9_FINDCLASS_FLAG_EXISTING_ONLY);
            // if ((NULL == classToCast) || (0 == instanceOfOrCheckCast(J9GC_J9OBJECT_CLAZZ(*address), classToCast))) {
            // The issue is that we can't simply call "internalFindClassUTF8" in DDR.
            // We could guess at the behaviour of the ClassLoader, but that makes
            // distingushing a real problem from a weird ClassLoader delegation
            // model difficult.
            }
            if (!numberOfReferences.eq(romClazz.objectStaticCount())) {
                result = J9MODRON_GCCHK_RC_CLASS_STATICS_WRONG_NUMBER_OF_REFERENCES;
                CheckError error = new CheckError(clazz, _cycle, _currentCheck, "Class ", result, _cycle.nextErrorCount());
                _reporter.report(error);
            }
        }
    } catch (CorruptDataException e) {
        // TODO : cde should be part of the error
        CheckError error = new CheckError(clazz, _cycle, _currentCheck, "Class ", J9MODRON_GCCHK_RC_CORRUPT_DATA_EXCEPTION, _cycle.nextErrorCount());
        _reporter.report(error);
    }
    return result;
}