static Address mapLimit(final int units, final int heads) {
// final int WORD_SIZE = ArchitecturalWord.getModel().bytesInWord();
final int WORD_SIZE = 4;
return baseAddress.plus(
Math.floorDiv(((units + heads + 1) * WORD_SIZE * 2) + (PAGE_SIZE - 1), PAGE_SIZE)
* PAGE_SIZE);
}
/**
* Store a value into a reference field of an object.
*
* @param object The object to store the field of.
* @param index The field index.
* @param value The value to store.
*/
public void storeReferenceField(ObjectReference object, int index, ObjectReference value) {
int limit = ObjectModel.getRefs(object);
if (Trace.isEnabled(Item.STORE) || ObjectModel.isWatched(object)) {
Trace.printf(
Item.STORE,
"[%s].object[%d/%d] = %s",
ObjectModel.getString(object),
index,
limit,
value.toString());
}
check(!object.isNull(), "Object can not be null");
check(index >= 0, "Index must be non-negative");
check(index < limit, "Index " + index + " out of bounds " + limit);
Address referenceSlot = ObjectModel.getRefSlot(object, index);
if (ActivePlan.constraints.needsWriteBarrier()) {
context.writeBarrier(object, referenceSlot, value, null, null, Plan.AASTORE_WRITE_BARRIER);
if (gcEveryWB) {
gc();
}
} else {
referenceSlot.store(value);
}
}
/**
* Copy numbytes from src to dst. Assumption either the ranges are non overlapping, or src >= dst
* + 4. Also, src and dst are 4 byte aligned and numBytes is a multiple of 4.
*
* @param dst the destination addr
* @param src the source addr
* @param numBytes the number of bytes top copy
*/
@Inline
public static void aligned32Copy(Address dst, Address src, Offset numBytes) {
if (USE_NATIVE && numBytes.sGT(Offset.fromIntSignExtend(NATIVE_THRESHOLD))) {
memcopy(dst, src, numBytes.toWord().toExtent());
} else {
if (VM.BuildFor64Addr) {
Word wordMask = Word.one().lsh(LOG_BYTES_IN_ADDRESS).minus(Word.one());
Word srcAlignment = src.toWord().and(wordMask);
if (srcAlignment.EQ(dst.toWord().and(wordMask))) {
Offset i = Offset.zero();
if (srcAlignment.EQ(Word.fromIntZeroExtend(BYTES_IN_INT))) {
dst.store(src.loadInt(i), i);
i = i.plus(BYTES_IN_INT);
}
Word endAlignment =
srcAlignment.plus(numBytes).and(Word.fromIntSignExtend(BYTES_IN_ADDRESS - 1));
numBytes = numBytes.minus(endAlignment.toOffset());
for (; i.sLT(numBytes); i = i.plus(BYTES_IN_ADDRESS)) {
dst.store(src.loadWord(i), i);
}
if (!endAlignment.isZero()) {
dst.store(src.loadInt(i), i);
}
return;
}
}
// normal case: 32 bit or (64 bit not aligned)
for (Offset i = Offset.zero(); i.sLT(numBytes); i = i.plus(BYTES_IN_INT)) {
dst.store(src.loadInt(i), i);
}
}
}
/**
* Takes the passed address and (atomically) performs any read barrier actions before returning it
* as an object.
*
* @param tmp The non-zero referent address
* @return The referent object.
*/
@Uninterruptible
@Inline
Object getInternal() {
if (RVMType.JavaLangRefReferenceReferenceField.madeTraced()) {
if (NEEDS_OBJECT_GETFIELD_BARRIER) {
return Barriers.objectFieldRead(
this,
RVMType.JavaLangRefReferenceReferenceField.getOffset(),
RVMType.JavaLangRefReferenceReferenceField.getId());
} else {
return Magic.getObjectAtOffset(
this,
RVMType.JavaLangRefReferenceReferenceField.getOffset(),
RVMType.JavaLangRefReferenceReferenceField.getId());
}
} else {
Address tmp = _referent;
if (tmp.isZero()) {
return null;
} else {
Object ref = Magic.addressAsObject(tmp);
if (Barriers.NEEDS_JAVA_LANG_REFERENCE_READ_BARRIER) {
ref = Barriers.javaLangReferenceReadBarrier(ref);
}
return ref;
}
}
}
/** All Scalars */
public static void scalar(Object object, TransitiveClosure trace) {
Address base = Magic.objectAsAddress(object);
int[] offsets = ObjectModel.getObjectType(object).asClass().getReferenceOffsets();
for (int i = 0; i < offsets.length; i++) {
trace.processEdge(ObjectReference.fromObject(object), base.plus(offsets[i]));
}
}
@Inline
private boolean acquireRecyclableBlockAddressOrder() {
if (recyclableExhausted) {
if (VM.VERIFY_ASSERTIONS && Options.verbose.getValue() >= 9) {
Log.writeln("[no recyclable available]");
}
return false;
}
int markState = 0;
boolean usable = false;
while (!usable) {
Address next = recyclableBlock.plus(BYTES_IN_BLOCK);
if (recyclableBlock.isZero() || ImmixSpace.isRecycleAllocChunkAligned(next)) {
recyclableBlock = space.acquireReusableBlocks();
if (recyclableBlock.isZero()) {
recyclableExhausted = true;
if (VM.VERIFY_ASSERTIONS && Options.verbose.getValue() >= 9) {
Log.writeln("[recyclable exhausted]");
}
line = LINES_IN_BLOCK;
return false;
}
} else {
recyclableBlock = next;
}
markState = Block.getBlockMarkState(recyclableBlock);
usable = (markState > 0 && markState <= ImmixSpace.getReusuableMarkStateThreshold(copy));
if (copy && Block.isDefragSource(recyclableBlock)) usable = false;
}
if (VM.VERIFY_ASSERTIONS) VM.assertions._assert(!Block.isUnused(recyclableBlock));
Block.setBlockAsReused(recyclableBlock);
lineUseCount += (LINES_IN_BLOCK - markState);
return true; // found something good
}
/** Reference Arrays */
public static void referenceArray(Object object, TransitiveClosure trace) {
Address base = Magic.objectAsAddress(object);
int length = ObjectModel.getArrayLength(object);
for (int i = 0; i < length; i++) {
trace.processEdge(ObjectReference.fromObject(object), base.plus(i << LOG_BYTES_IN_ADDRESS));
}
}
/**
* Test whether a memory range is set to a given integer value
*
* @param start The address to start checking at
* @param bytes The size of the region to check, in bytes
* @param verbose If true, produce verbose output
* @param value The value to which the memory should be set
*/
private static boolean isSet(Address start, int bytes, boolean verbose, int value)
/* Inlining this loop into the uninterruptible code can
* cause/encourage the GCP into moving a get_obj_tib into the
* interruptible region where the tib is being installed via an
* int_store
*/
throws NoInlinePragma {
if (Assert.VERIFY_ASSERTIONS) assertAligned(bytes);
for (int i = 0; i < bytes; i += BYTES_IN_INT)
if (start.loadInt(Offset.fromInt(i)) != value) {
if (verbose) {
Log.prependThreadId();
Log.write("Memory range does not contain only value ");
Log.writeln(value);
Log.write("Non-zero range: ");
Log.write(start);
Log.write(" .. ");
Log.writeln(start.add(bytes));
Log.write("First bad value at ");
Log.writeln(start.add(i));
dumpMemory(start, 0, bytes);
}
return false;
}
return true;
}
/**
* Push an address onto the address stack.
*
* @param object the object to be pushed onto the object queue
*/
@Inline
public final void push(ObjectReference object) {
Address addr = object.toAddress();
if (VM.VERIFY_ASSERTIONS) VM.assertions._assert(!addr.isZero());
checkHeadInsert(1);
uncheckedHeadInsert(addr);
}
/**
* Set a region of memory
*
* @param start The start of the region to be zeroed (must be 4-byte aligned)
* @param bytes The number of bytes to be zeroed (must be 4-byte aligned)
* @param value The value to which the integers in the region should be set
*/
public static void set(Address start, int bytes, int value) throws InlinePragma {
if (Assert.VERIFY_ASSERTIONS) {
assertAligned(start);
assertAligned(bytes);
}
Address end = start.add(bytes);
for (Address addr = start; addr.LT(end); addr = addr.add(BYTES_IN_INT)) addr.store(value);
}
/**
* Zero a small region of memory
*
* @param start The start of the region to be zeroed (must be 4-byte aligned)
* @param bytes The number of bytes to be zeroed (must be 4-byte aligned)
*/
public static void zeroSmall(Address start, Extent bytes) throws InlinePragma {
if (Assert.VERIFY_ASSERTIONS) {
assertAligned(start);
assertAligned(bytes);
}
Address end = start.add(bytes);
for (Address addr = start; addr.LT(end); addr = addr.add(BYTES_IN_INT)) addr.store(0);
}
/**
* Given a slot (ie the address of an ObjectReference), ensure that the referent will not move for
* the rest of the GC. This is achieved by calling the precopyObject method.
*
* @param slot The slot to check
*/
@Inline
public final void processPrecopyEdge(Address slot) {
ObjectReference child = slot.loadObjectReference();
if (!child.isNull()) {
child = precopyObject(child);
slot.store(child);
}
}
/** Called after we've successfully loaded the shared library */
private void callOnLoad() {
// Run any JNI_OnLoad functions defined within the library
Address JNI_OnLoadAddress = getSymbol("JNI_OnLoad");
if (!JNI_OnLoadAddress.isZero()) {
int version = runJNI_OnLoad(JNI_OnLoadAddress);
checkJNIVersion(version);
}
}
/**
* Resolve a symbol to an address in a currently loaded dynamic library.
*
* @return the address of the symbol of Address.zero() if it cannot be resolved
*/
public static synchronized Address resolveSymbol(String symbol) {
for (VM_DynamicLibrary lib : dynamicLibraries.values()) {
Address symbolAddress = lib.getSymbol(symbol);
if (!symbolAddress.isZero()) {
return symbolAddress;
}
}
return Address.zero();
}
/** Sweep through the large pages, releasing all superpages on the "from space" treadmill. */
private void sweepLargePages(boolean sweepNursery) {
while (true) {
Address cell = sweepNursery ? treadmill.popNursery() : treadmill.pop();
if (cell.isZero()) break;
release(getSuperPage(cell));
}
if (VM.VERIFY_ASSERTIONS)
VM.assertions._assert(sweepNursery ? treadmill.nurseryEmpty() : treadmill.fromSpaceEmpty());
}
/**
* Store a value into the data field of an object.
*
* @param object The object to store the field of.
* @param index The field index.
* @param value The value to store.
*/
public void storeDataField(ObjectReference object, int index, int value) {
int limit = ObjectModel.getDataCount(object);
check(!object.isNull(), "Object can not be null");
check(index >= 0, "Index must be non-negative");
check(index < limit, "Index " + index + " out of bounds " + limit);
Address ref = ObjectModel.getDataSlot(object, index);
ref.store(value);
Trace.trace(Item.STORE, "%s.[%d] = %d", object.toString(), index, value);
}
/**
* Demand zero mmaps an area of virtual memory.
*
* @param start the address of the start of the area to be mapped
* @param size the size, in bytes, of the area to be mapped
* @return 0 if successful, otherwise the system errno
*/
public final int dzmmap(Address start, int size) {
Address result = org.jikesrvm.runtime.Memory.dzmmap(start, Extent.fromIntZeroExtend(size));
if (result.EQ(start)) return 0;
if (result.GT(Address.fromIntZeroExtend(127))) {
VM.sysWrite("demand zero mmap with MAP_FIXED on ", start);
VM.sysWriteln(" returned some other address", result);
VM.sysFail("mmap with MAP_FIXED has unexpected behavior");
}
return result.toInt();
}
public EEPRO100TxFD(ResourceManager rm) {
// Create a large enough buffer
final int size = (TxFDSize + DataBufferSize) + 16 /* alignment */;
this.data = new byte[size];
this.mem = rm.asMemoryResource(data);
final Address memAddr = mem.getAddress();
this.firstDPDOffset = 0;
this.firstDPDAddress = memAddr.add(firstDPDOffset);
}
/**
* Load and return the value of a data field of an object.
*
* @param object The object to load the field of.
* @param index The field index.
*/
public int loadDataField(ObjectReference object, int index) {
int limit = ObjectModel.getDataCount(object);
check(!object.isNull(), "Object can not be null");
check(index >= 0, "Index must be non-negative");
check(index < limit, "Index " + index + " out of bounds " + limit);
Address dataSlot = ObjectModel.getDataSlot(object, index);
int result = dataSlot.loadInt();
Trace.trace(
Item.LOAD, "[%s].int[%d] returned [%d]", ObjectModel.getString(object), index, result);
return result;
}
/**
* Low level copy of <code>copyBytes</code> bytes from <code>src[srcPos]</code> to <code>
* dst[dstPos]</code>.
*
* <p>Assumption <code>src != dst || (srcPos >= dstPos)</code> and element size is 8 bytes.
*
* @param dstPtr The destination start address
* @param srcPtr The source start address
* @param copyBytes The number of bytes to be copied
*/
public static void aligned64Copy(Address dstPtr, Address srcPtr, int copyBytes) {
if (USE_NATIVE && copyBytes > NATIVE_THRESHOLD) {
memcopy(dstPtr, srcPtr, copyBytes);
} else {
// The elements of long[] and double[] are always doubleword aligned
// therefore we can do 64 bit load/stores without worrying about alignment.
Address endPtr = srcPtr.plus(copyBytes);
while (srcPtr.LT(endPtr)) {
copy8Bytes(dstPtr, srcPtr);
srcPtr = srcPtr.plus(8);
dstPtr = dstPtr.plus(8);
}
}
}
// return (address of) next ref in the current "frame" on the
// threads JNIEnvironment stack of refs
// When at the end of the current frame, update register locations to point
// to the non-volatile registers saved in the JNI transition frame.
//
public Address getNextReferenceAddress() {
// first report jni refs in the current frame in the jniRef side stack
// until all in the frame are reported
//
if (jniNextRef > jniFramePtr) {
Address ref_address = Magic.objectAsAddress(jniRefs).plus(jniNextRef);
jniNextRef -= BYTES_IN_ADDRESS;
return ref_address;
}
// no more refs to report, before returning 0, setup for processing
// the next jni frame, if any
// jniNextRef -> savedFramePtr for another "frame" of refs for another
// sequence of Native C frames lower in the stack, or to 0 if this is the
// last jni frame in the JNIRefs stack. If more frames, initialize for a
// later scan of those refs.
//
if (jniFramePtr > 0) {
jniFramePtr = jniRefs.get(jniFramePtr >> LOG_BYTES_IN_ADDRESS).toInt();
jniNextRef = jniNextRef - BYTES_IN_ADDRESS;
}
// set register locations for non-volatiles to point to registers saved in
// the JNI transition frame at a fixed negative offset from the callers FP.
// the save non-volatiles are EBX EBP and EDI.
//
registerLocations.set(EDI.value(), framePtr.plus(JNICompiler.EDI_SAVE_OFFSET));
registerLocations.set(EBX.value(), framePtr.plus(JNICompiler.EBX_SAVE_OFFSET));
registerLocations.set(EBP.value(), framePtr.plus(JNICompiler.EBP_SAVE_OFFSET));
return Address.zero(); // no more refs to report
}
private void zeroBlock(Address block) {
// FIXME: efficiency check here!
if (VM.VERIFY_ASSERTIONS)
VM.assertions._assert(
block.toWord().and(Word.fromIntSignExtend(BYTES_IN_BLOCK - 1)).isZero());
VM.memory.zero(block, Extent.fromIntZeroExtend(BYTES_IN_BLOCK));
}
public static void dumpMemory(Address start, int beforeBytes, int afterBytes) {
beforeBytes = alignDown(beforeBytes, BYTES_IN_ADDRESS);
afterBytes = alignUp(afterBytes, BYTES_IN_ADDRESS);
VM.sysWrite("---- Dumping memory from ");
VM.sysWrite(start.minus(beforeBytes));
VM.sysWrite(" to ");
VM.sysWrite(start.plus(afterBytes));
VM.sysWrite(" ----\n");
for (int i = -beforeBytes; i < afterBytes; i += BYTES_IN_ADDRESS) {
VM.sysWrite(i, ": ");
VM.sysWrite(start.plus(i));
Word value = start.plus(i).loadWord();
VM.sysWriteln(" ", value);
}
}
/**
* Gets the compiled code of a given stackframe.
*
* @param sf Stackframe pointer
* @return The compiled code
*/
final VmCompiledCode getCompiledCode(Address sf) {
final int ccid = sf.loadInt(getMethodIdOffset(sf));
if (ccid == 0) {
return null;
} else {
return VmUtils.getVm().getCompiledMethods().get(ccid);
}
}
@Inline
public static Address alignUp(Address address, int alignment) {
return address
.plus(alignment - 1)
.toWord()
.and(Word.fromIntSignExtend(~(alignment - 1)))
.toAddress();
}
/**
* Pop an address from the address stack, return zero if the stack is empty.
*
* @return The next address in the address stack, or zero if the stack is empty
*/
@Inline
public final Address pop() {
if (checkDequeue(1)) {
return uncheckedDequeue();
} else {
return Address.zero();
}
}
/**
* Allocate space for a new object. This is frequently executed code and the coding is
* deliberaetly sensitive to the optimizing compiler. After changing this, always check the IR/MC
* that is generated.
*
* @param bytes The number of bytes allocated
* @param align The requested alignment
* @param offset The offset from the alignment
* @return The address of the first byte of the allocated region
*/
@Inline
public final Address alloc(int bytes, int align, int offset) {
/* establish how much we need */
Address start = alignAllocationNoFill(cursor, align, offset);
Address end = start.plus(bytes);
/* check whether we've exceeded the limit */
if (end.GT(limit)) {
if (bytes > BYTES_IN_LINE) return overflowAlloc(bytes, align, offset);
else return allocSlowHot(bytes, align, offset);
}
/* sufficient memory is available, so we can finish performing the allocation */
fillAlignmentGap(cursor, start);
cursor = end;
return start;
}
/**
* Gets the previous frame (if any)
*
* @param sf The stackframe to get the previous frame from.
* @return The previous frame or null.
*/
@KernelSpace
@Internal
public final Address getPrevious(Address sf) {
if (isValid(sf)) {
return sf.loadAddress(getPreviousOffset(sf));
} else {
return null;
}
}
/**
* Trace a reference during GC. This involves determining which collection policy applies and
* calling the appropriate <code>trace</code> method.
*
* @param target The object the interior edge points within.
* @param slot The location of the interior edge.
* @param root True if this is a root edge.
*/
public final void processInteriorEdge(ObjectReference target, Address slot, boolean root) {
Address interiorRef = slot.loadAddress();
Offset offset = interiorRef.diff(target.toAddress());
ObjectReference newTarget = traceObject(target, root);
if (VM.VERIFY_ASSERTIONS) {
if (offset.sLT(Offset.zero()) || offset.sGT(Offset.fromIntSignExtend(1 << 24))) {
// There is probably no object this large
Log.writeln("ERROR: Suspiciously large delta to interior pointer");
Log.write(" object base = ");
Log.writeln(target);
Log.write(" interior reference = ");
Log.writeln(interiorRef);
Log.write(" delta = ");
Log.writeln(offset);
VM.assertions._assert(false);
}
}
slot.store(newTarget.toAddress().plus(offset));
}
/**
* Allocate space for a new object. This is frequently executed code and the coding is
* deliberaetly sensitive to the optimizing compiler. After changing this, always check the IR/MC
* that is generated.
*
* @param bytes The number of bytes allocated
* @param align The requested alignment
* @param offset The offset from the alignment
* @return The address of the first byte of the allocated region
*/
public final Address overflowAlloc(int bytes, int align, int offset) {
/* establish how much we need */
Address start = alignAllocationNoFill(largeCursor, align, offset);
Address end = start.plus(bytes);
/* check whether we've exceeded the limit */
if (end.GT(largeLimit)) {
requestForLarge = true;
Address rtn = allocSlowInline(bytes, align, offset);
requestForLarge = false;
return rtn;
}
/* sufficient memory is available, so we can finish performing the allocation */
fillAlignmentGap(largeCursor, start);
largeCursor = end;
return start;
}