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8004330: Add missing Unsafe entry points for addAndGet() family

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Add Unsafe addAndGet() methods which have intrinsics in Hotspot (7023898)

Reviewed-by: alanb, kvn
This commit is contained in:
Doug Lea 2012-12-20 12:24:52 -08:00
parent d8b54b1219
commit f2c8fd3d1a
1 changed files with 102 additions and 0 deletions
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102
jdk/src/share/classes/sun/misc/Unsafe.java
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@ -1009,21 +1009,123 @@ public final class Unsafe {
*/
public native int getLoadAverage(double[] loadavg, int nelems);
// The following contain CAS-based Java implementations used on
// platforms not supporting native instructions
/**
* Atomically adds the given value to the current value of a field
* or array element within the given object <code>o</code>
* at the given <code>offset</code>.
*
* @param o object/array to update the field/element in
* @param offset field/element offset
* @param delta the value to add
* @return the previous value
* @since 1.8
*/
public final int getAndAddInt(Object o, long offset, int delta) {
int v;
do {
v = getIntVolatile(o, offset);
} while (!compareAndSwapInt(o, offset, v, v + delta));
return v;
}
/**
* Atomically adds the given value to the current value of a field
* or array element within the given object <code>o</code>
* at the given <code>offset</code>.
*
* @param o object/array to update the field/element in
* @param offset field/element offset
* @param delta the value to add
* @return the previous value
* @since 1.8
*/
public final long getAndAddLong(Object o, long offset, long delta) {
long v;
do {
v = getLongVolatile(o, offset);
} while (!compareAndSwapLong(o, offset, v, v + delta));
return v;
}
/**
* Atomically exchanges the given value with the current value of
* a field or array element within the given object <code>o</code>
* at the given <code>offset</code>.
*
* @param o object/array to update the field/element in
* @param offset field/element offset
* @param newValue new value
* @return the previous value
* @since 1.8
*/
public final int getAndSetInt(Object o, long offset, int newValue) {
int v;
do {
v = getIntVolatile(o, offset);
} while (!compareAndSwapInt(o, offset, v, newValue));
return v;
}
/**
* Atomically exchanges the given value with the current value of
* a field or array element within the given object <code>o</code>
* at the given <code>offset</code>.
*
* @param o object/array to update the field/element in
* @param offset field/element offset
* @param newValue new value
* @return the previous value
* @since 1.8
*/
public final long getAndSetLong(Object o, long offset, long newValue) {
long v;
do {
v = getLongVolatile(o, offset);
} while (!compareAndSwapLong(o, offset, v, newValue));
return v;
}
/**
* Atomically exchanges the given reference value with the current
* reference value of a field or array element within the given
* object <code>o</code> at the given <code>offset</code>.
*
* @param o object/array to update the field/element in
* @param offset field/element offset
* @param newValue new value
* @return the previous value
* @since 1.8
*/
public final Object getAndSetObject(Object o, long offset, Object newValue) {
Object v;
do {
v = getObjectVolatile(o, offset);
} while (!compareAndSwapObject(o, offset, v, newValue));
return v;
}
/**
* Ensures lack of reordering of loads before the fence
* with loads or stores after the fence.
* @since 1.8
*/
public native void loadFence();
/**
* Ensures lack of reordering of stores before the fence
* with loads or stores after the fence.
* @since 1.8
*/
public native void storeFence();
/**
* Ensures lack of reordering of loads or stores before the fence
* with loads or stores after the fence.
* @since 1.8
*/
public native void fullFence();