com.oracle.svm.core.heap

Class NoAllocationVerifier

java.lang.Object

com.oracle.svm.core.heap.NoAllocationVerifier

All Implemented Interfaces:

AutoCloseable

public class NoAllocationVerifier
extends Object
implements AutoCloseable

Motivation: Open an instance of this class to detect attempts to allocate in the Heap. Design: There shouldn't be tests for a locked heap on the allocation fast-path, so the key is that creating one of these sets top to end in the young space, so allocation attempts fail over to the slow-path, and there can be a test for a locked heap on the slow path. TODO: When SVM becomes multi-threaded, this should only prevent allocation on a particular thread. That could be done by setting the thread's TLAB to null, which should force it on to the slow-path to allocation a new TLAB.

Field Summary

Fields

Modifier and Type	Field and Description
static String	ERROR_MSG

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	NoAllocationVerifier(String reason)

Method Summary

Modifier and Type	Method and Description
void	close()
static void	exit(String callSite, String typeName) A guard to place before an allocation, giving the call site and the allocation type.
static NoAllocationVerifier	factory(String reason) Create an opened instance.
static NoAllocationVerifier	factory(String reason, boolean open) Create an instance that can be opened lazily.
static boolean	isActive() Returns true if there is an open NoAllocationVerifier, i.e., returns true if no allocation is allowed in this thread.
NoAllocationVerifier	open()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ERROR_MSG

public static final String ERROR_MSG

See Also:

Constant Field Values

Constructor Detail

NoAllocationVerifier

protected NoAllocationVerifier(String reason)

Method Detail

exit

public static void exit(String callSite,
                        String typeName)

A guard to place before an allocation, giving the call site and the allocation type.

factory

public static NoAllocationVerifier factory(String reason)

Create an opened instance. Usage is:

     try (NoAllocationVerifier verifier = NoAllocationVerifier.factory()) {
         ....
     }
 

factory

public static NoAllocationVerifier factory(String reason,
                                           boolean open)

Create an instance that can be opened lazily. Usage is:

     NoAllocationVerifier instance = NoAllocationVerifier.factory(false);
     ....
     try(NoAllocationVerifier resource = instance.open()) {
         ....
     }
 

isActive

public static boolean isActive()

Returns true if there is an open NoAllocationVerifier, i.e., returns true if no allocation is allowed in this thread.

open

public NoAllocationVerifier open()

close

public void close()

Specified by:

close in interface AutoCloseable