backup/JWebAssembly
1
0
Fork 0
mirror of https://github.com/i-net-software/JWebAssembly.git synced 2025-03-14 18:43:27 +01:00
Code Issues Projects Releases Activity

AtomicReferenceFieldUpdater is another alternative for Unsafe

Browse Source
This commit is contained in:
Volker Berlin 2023-02-26 13:15:24 +01:00
parent adc21c25df
commit b254aae288
No known key found for this signature in database
GPG Key ID: 988423EF815BE4CB
2 changed files with 20 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
src/de/inetsoftware/jwebassembly/module/FunctionManager.java
View File

@ -1,5 +1,5 @@
/*
* Copyright 2018 - 2022 Volker Berlin (i-net software)
* Copyright 2018 - 2023 Volker Berlin (i-net software)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@ -173,6 +173,7 @@ class FunctionManager {
switch( name.className ) {
case UnsafeManager.UNSAFE_8:
case UnsafeManager.UNSAFE_11:
case UnsafeManager.FIELDUPDATER:
case UnsafeManager.VARHANDLE:
// Unsafe method call will be replaces by the UnsafeManager
return name;

21
src/de/inetsoftware/jwebassembly/module/UnsafeManager.java
View File

@ -75,6 +75,9 @@ class UnsafeManager {
/** Unsafe class bane in Java 11 */
static final String UNSAFE_11 = "jdk/internal/misc/Unsafe";
/** Wrapper for Unsafe */
static final String FIELDUPDATER = "java/util/concurrent/atomic/AtomicReferenceFieldUpdater";
/** VARHANDLE as modern replacement of Unsafe */
static final String VARHANDLE = "java/lang/invoke/VarHandle";
@ -110,6 +113,7 @@ class UnsafeManager {
switch( callInst.getFunctionName().className ) {
case UNSAFE_8:
case UNSAFE_11:
case FIELDUPDATER:
patch( instructions, i, callInst );
break;
case VARHANDLE:
@ -144,7 +148,10 @@ class UnsafeManager {
patch_objectFieldOffset_Java8( instructions, idx, callInst );
break;
case "jdk/internal/misc/Unsafe.objectFieldOffset(Ljava/lang/Class;Ljava/lang/String;)J":
patch_objectFieldOffset_Java11( instructions, idx, callInst );
patch_objectFieldOffset_Java11( instructions, idx, callInst, false );
break;
case "java/util/concurrent/atomic/AtomicReferenceFieldUpdater.newUpdater(Ljava/lang/Class;Ljava/lang/Class;Ljava/lang/String;)Ljava/util/concurrent/atomic/AtomicReferenceFieldUpdater;":
patch_objectFieldOffset_Java11( instructions, idx, callInst, true );
break;
case "sun/misc/Unsafe.arrayBaseOffset(Ljava/lang/Class;)I":
case "jdk/internal/misc/Unsafe.arrayBaseOffset(Ljava/lang/Class;)I":
@ -156,6 +163,7 @@ class UnsafeManager {
break;
case "sun/misc/Unsafe.getObjectVolatile(Ljava/lang/Object;J)Ljava/lang/Object;":
case "sun/misc/Unsafe.getInt(Ljava/lang/Object;J)I":
case "sun/misc/Unsafe.getLong(Ljava/lang/Object;J)J":
patchFieldFunction( instructions, idx, callInst, name, 1 );
break;
case "sun/misc/Unsafe.getAndAddInt(Ljava/lang/Object;JI)I":
@ -189,6 +197,9 @@ class UnsafeManager {
case "jdk/internal/misc/Unsafe.compareAndSetObject(Ljava/lang/Object;JLjava/lang/Object;Ljava/lang/Object;)Z":
patchFieldFunction( instructions, idx, callInst, name, 3 );
break;
case "java/util/concurrent/atomic/AtomicReferenceFieldUpdater.compareAndSet(Ljava/lang/Object;Ljava/lang/Object;Ljava/lang/Object;)Z":
patchFieldFunction( instructions, idx, callInst, name, 4 );
break;
case "jdk/internal/misc/Unsafe.getLongUnaligned(Ljava/lang/Object;J)J":
case "jdk/internal/misc/Unsafe.getIntUnaligned(Ljava/lang/Object;J)I":
case "jdk/internal/misc/Unsafe.getCharUnaligned(Ljava/lang/Object;JZ)C":
@ -360,8 +371,10 @@ class UnsafeManager {
* the index in the instructions
* @param callInst
* the method call to Unsafe
* @param isAtomicReferenceFieldUpdater
* true, if is AtomicReferenceFieldUpdater
*/
private void patch_objectFieldOffset_Java11( List<WasmInstruction> instructions, int idx, WasmCallInstruction callInst ) {
private void patch_objectFieldOffset_Java11( List<WasmInstruction> instructions, int idx, WasmCallInstruction callInst, boolean isAtomicReferenceFieldUpdater ) {
UnsafeState state = findUnsafeState( instructions, idx );
// objectFieldOffset() has 3 parameters THIS(Unsafe), class and the fieldname
@ -372,7 +385,8 @@ class UnsafeManager {
state.fieldName = ((WasmConstStringInstruction)stackValue.instr).getValue();
// find the class value on which getDeclaredField is called
stackValue = StackInspector.findInstructionThatPushValue( paramInstructions, 2, callInst.getCodePosition() );
int classParamIdx = isAtomicReferenceFieldUpdater ? 3 : 2;
stackValue = StackInspector.findInstructionThatPushValue( paramInstructions, classParamIdx, callInst.getCodePosition() );
state.typeName = getClassConst( instructions, stackValue );
nop( instructions, from, idx + 2 );
@ -483,6 +497,7 @@ class UnsafeManager {
case "compareAndSwapInt":
case "compareAndSwapLong":
case "compareAndSwapObject":
case "compareAndSet": // AtomicReferenceFieldUpdater
AnyType type = paramTypes[3];
if( type.isRefType() ) {
type = ValueType.ref;