com.oracle.svm.core.windows

Class WindowsOSCommittedMemoryProvider

java.lang.Object

com.oracle.svm.core.os.AbstractCommittedMemoryProvider

com.oracle.svm.core.os.OSCommittedMemoryProvider

com.oracle.svm.core.windows.WindowsOSCommittedMemoryProvider

All Implemented Interfaces:

CommittedMemoryProvider

public class WindowsOSCommittedMemoryProvider
extends OSCommittedMemoryProvider

As it is not possible to free a subrange of the allocated address range on Windows, the main purpose of this class is to adjust how the aligned blocks of committed memory are allocated and freed to circumvent this restriction.

Nested Class Summary

Nested classes/interfaces inherited from class com.oracle.svm.core.os.OSCommittedMemoryProvider

OSCommittedMemoryProvider.VirtualMemoryTracker

Nested classes/interfaces inherited from interface com.oracle.svm.core.os.CommittedMemoryProvider

CommittedMemoryProvider.Access

Field Summary

Fields inherited from interface com.oracle.svm.core.os.CommittedMemoryProvider

UNALIGNED

Constructor Summary

Constructors

Constructor and Description
WindowsOSCommittedMemoryProvider()

Method Summary

Modifier and Type	Method and Description
org.graalvm.word.Pointer	allocate(org.graalvm.word.UnsignedWord size, org.graalvm.word.UnsignedWord alignment, boolean executable) Allocate the requested amount of virtual memory at the requested alignment.
boolean	free(org.graalvm.word.PointerBase start, org.graalvm.word.UnsignedWord size, org.graalvm.word.UnsignedWord alignment, boolean executable) Release a block of committed memory that was allocated with CommittedMemoryProvider.allocate(org.graalvm.word.UnsignedWord, org.graalvm.word.UnsignedWord, boolean), requiring the exact same parameter values that were originally passed to CommittedMemoryProvider.allocate(org.graalvm.word.UnsignedWord, org.graalvm.word.UnsignedWord, boolean).

Methods inherited from class com.oracle.svm.core.os.OSCommittedMemoryProvider

allocate, defaultAlignment, defaultProtection, free, initialize, tearDown

Methods inherited from class com.oracle.svm.core.os.AbstractCommittedMemoryProvider

protect

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.oracle.svm.core.os.CommittedMemoryProvider

afterGarbageCollection, beforeGarbageCollection, get, getGranularity

Constructor Detail

WindowsOSCommittedMemoryProvider

public WindowsOSCommittedMemoryProvider()

Method Detail

allocate

public org.graalvm.word.Pointer allocate(org.graalvm.word.UnsignedWord size,
                                         org.graalvm.word.UnsignedWord alignment,
                                         boolean executable)

Description copied from class: OSCommittedMemoryProvider

Allocate the requested amount of virtual memory at the requested alignment.

Specified by:

allocate in interface CommittedMemoryProvider

Overrides:

allocate in class OSCommittedMemoryProvider

Parameters:

size - The number of bytes to allocate, which is rounded up to the next multiple of the granularity if required.

alignment - The required alignment of the block start, or CommittedMemoryProvider.UNALIGNED.

executable - Whether the block must be executable.

Returns:

A Pointer to the aligned memory, or a null Pointer.

free

public boolean free(org.graalvm.word.PointerBase start,
                    org.graalvm.word.UnsignedWord size,
                    org.graalvm.word.UnsignedWord alignment,
                    boolean executable)

Description copied from interface: CommittedMemoryProvider

Release a block of committed memory that was allocated with CommittedMemoryProvider.allocate(org.graalvm.word.UnsignedWord, org.graalvm.word.UnsignedWord, boolean), requiring the exact same parameter values that were originally passed to CommittedMemoryProvider.allocate(org.graalvm.word.UnsignedWord, org.graalvm.word.UnsignedWord, boolean).

Specified by:

free in interface CommittedMemoryProvider

Overrides:

free in class OSCommittedMemoryProvider

Parameters:

start - The start of the memory block, as returned by CommittedMemoryProvider.allocate(org.graalvm.word.UnsignedWord, org.graalvm.word.UnsignedWord, boolean).

size - The originally requested size in bytes.

alignment - The originally requested alignment.

executable - Whether the block was requested to be executable.

Returns:

true on success, or false otherwise.