3 files changed, 12 insertions, 6 deletions
diff --git a/libjava/java/nio/DirectByteBufferImpl.java b/libjava/java/nio/DirectByteBufferImpl.java
index 7c2b783..be0fc52 100644
--- a/libjava/java/nio/DirectByteBufferImpl.java
+++ b/libjava/java/nio/DirectByteBufferImpl.java
@@ -136,15 +136,20 @@ final class DirectByteBufferImpl extends ByteBuffer
     return this;
   }
   
-  native void shiftDown (int dst_offset, int src_offset, int count);
+  static native void shiftDown(RawData address, int dst_offset, int src_offset, int count);
 
+  void shiftDown(int dst_offset, int src_offset, int count)
+  {
+    shiftDown(address, dst_offset, src_offset, count);
+  }
+  
   public ByteBuffer compact ()
   {
     int pos = position();
     if (pos > 0)
       {
 	int count = remaining();
-	shiftDown(0, pos, count);
+	shiftDown(address, 0, pos, count);
 	position(count);
 	limit(capacity());
       }
diff --git a/libjava/java/nio/MappedByteBufferImpl.java b/libjava/java/nio/MappedByteBufferImpl.java
index ccd987e..5932c99 100644
--- a/libjava/java/nio/MappedByteBufferImpl.java
+++ b/libjava/java/nio/MappedByteBufferImpl.java
@@ -121,7 +121,8 @@ final class MappedByteBufferImpl extends MappedByteBuffer
     if (pos > 0)
       {
 	int count = remaining();
-	shiftDown(0, pos, count);
+	// Call shiftDown method optimized for direct buffers.
+	DirectByteBufferImpl.shiftDown(address, 0, pos, count);
 	position(count);
 	limit(capacity());
       }
diff --git a/libjava/java/nio/natDirectByteBufferImpl.cc b/libjava/java/nio/natDirectByteBufferImpl.cc
index 94225c3..88f53fc 100644
--- a/libjava/java/nio/natDirectByteBufferImpl.cc
+++ b/libjava/java/nio/natDirectByteBufferImpl.cc
@@ -65,9 +65,9 @@ java::nio::DirectByteBufferImpl::adjustAddress (RawData* address, jint offset)
 
 void
 java::nio::DirectByteBufferImpl::shiftDown
-(jint dst_offset, jint src_offset, jint count)
+(RawData* address, jint dst_offset, jint src_offset, jint count)
 {
-  jbyte* dst = reinterpret_cast<jbyte*> (address) + array_offset + dst_offset;
-  jbyte* src = reinterpret_cast<jbyte*> (address) + array_offset + src_offset;
+  jbyte* dst = reinterpret_cast<jbyte*> (address) + dst_offset;
+  jbyte* src = reinterpret_cast<jbyte*> (address) + src_offset;
   ::memmove(dst, src, count);
 }