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8266627: CLinker allocateMemory, freeMemory implementation should not…
… use default lookup

Reviewed-by: jvernee
  • Loading branch information
mcimadamore committed May 6, 2021
1 parent e8043ed commit d0a7098c48af49e67879aa6d3fcef6300df6f180
@@ -0,0 +1,40 @@
/*
* Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/

#include <stdlib.h>

#include "jni.h"

JNIEXPORT void JNICALL
Java_jdk_internal_foreign_abi_VMFunctions_initVMFunctions(JNIEnv *env,
jclass cls,
jlong address)
{
size_t* addresses = (size_t*)(void*)address;
// The order in which the function pointers are stored has to match the order of constants
// in the VMFunctions.FunctionName enum.
addresses[0] = (size_t)&malloc;
addresses[1] = (size_t)&free;
}
@@ -50,7 +50,6 @@
import java.lang.invoke.VarHandle;
import java.lang.ref.Reference;
import java.nio.charset.Charset;
import java.nio.file.Path;
import java.util.List;
import java.util.Map;
import java.util.function.Consumer;
@@ -412,39 +411,17 @@ static MethodHandle wrapWithAllocator(MethodHandle specializedHandle,
return specializedHandle;
}

// lazy init MH_ALLOC and MH_FREE handles
private static class AllocHolder {

private static final CLinker linker = getSystemLinker();

static {
// FIXME: This should go away. This is temporary hack to get testing on Windows going.
// After fix for 8266627, this whole section will be removed.
if (linker instanceof Windowsx64Linker) {
System.load(Path.of(System.getenv("SystemRoot"), "System32", "msvcrt.dll").toAbsolutePath().toString());
}
}

static final MethodHandle MH_MALLOC = linker.downcallHandle(CLinker.findNative("malloc").get(),
MethodType.methodType(MemoryAddress.class, long.class),
FunctionDescriptor.of(C_POINTER, C_LONG_LONG));

static final MethodHandle MH_FREE = linker.downcallHandle(CLinker.findNative("free").get(),
MethodType.methodType(void.class, MemoryAddress.class),
FunctionDescriptor.ofVoid(C_POINTER));
}

public static MemoryAddress allocateMemoryInternal(long size) {
try {
return (MemoryAddress) AllocHolder.MH_MALLOC.invokeExact(size);
return (MemoryAddress) VMFunctions.MH_MALLOC.invokeExact(size);
} catch (Throwable th) {
throw new RuntimeException(th);
}
}

public static void freeMemoryInternal(MemoryAddress addr) {
try {
AllocHolder.MH_FREE.invokeExact(addr);
VMFunctions.MH_FREE.invokeExact(addr);
} catch (Throwable th) {
throw new RuntimeException(th);
}
@@ -0,0 +1,81 @@
/*
* Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/

package jdk.internal.foreign.abi;

import jdk.incubator.foreign.CLinker;
import jdk.incubator.foreign.FunctionDescriptor;
import jdk.incubator.foreign.MemoryAccess;
import jdk.incubator.foreign.MemoryAddress;
import jdk.incubator.foreign.MemoryLayouts;
import jdk.incubator.foreign.MemorySegment;
import jdk.incubator.foreign.ResourceScope;

import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodType;

import static jdk.incubator.foreign.CLinker.C_LONG_LONG;
import static jdk.incubator.foreign.CLinker.C_POINTER;

/**
* This class is used to setup downcall method handles which refer to commonly used functions within the JVM.
* A memory segment is allocated, with enough room to contain as many pointers as the number of constants
* defined in {@link FunctionName}. This segment is then filled by the JVM with function pointers which target
* the desired functions.
*/
class VMFunctions {

/**
* The order of these constants has to match that in which the VM will fill the {@code vmFunctions} pointer array.
*/
enum FunctionName {
MALLOC,
FREE;

MemoryAddress get() {
return MemoryAccess.getAddressAtIndex(vmFunctions, ordinal());
}
}

private static final CLinker linker = SharedUtils.getSystemLinker();
private static final MemorySegment vmFunctions;

static {
vmFunctions = MemorySegment.allocateNative(
MemoryLayouts.ADDRESS.byteSize() * FunctionName.values().length,
ResourceScope.newImplicitScope());
initVMFunctions(vmFunctions.address().toRawLongValue());
}

static final MethodHandle MH_MALLOC = linker.downcallHandle(FunctionName.MALLOC.get(),
MethodType.methodType(MemoryAddress.class, long.class),
FunctionDescriptor.of(C_POINTER, C_LONG_LONG));

static final MethodHandle MH_FREE = linker.downcallHandle(FunctionName.FREE.get(),
MethodType.methodType(void.class, MemoryAddress.class),
FunctionDescriptor.ofVoid(C_POINTER));

static native void initVMFunctions(long address);
}

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