--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/Compiler/src/com/sun/c1x/alloc/LIRInsertionBuffer.java	Wed Apr 27 11:43:22 2011 +0200
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2009, 2010, 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.
+ *
+ * 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 com.sun.c1x.alloc;
+
+import java.util.*;
+
+import com.sun.c1x.lir.*;
+import com.sun.c1x.util.*;
+import com.sun.cri.ci.*;
+
+/**
+ *
+ * @author Thomas Wuerthinger
+ */
+public final class LIRInsertionBuffer {
+
+    private LIRList lir; // the lir list where ops of this buffer should be inserted later (null when uninitialized)
+
+    // list of insertion points. index and count are stored alternately:
+    // indexAndCount[i * 2]: the index into lir list where "count" ops should be inserted
+    // indexAndCount[i * 2 + 1]: the number of ops to be inserted at index
+    private final IntList indexAndCount;
+
+    // the LIROps to be inserted
+    private final List<LIRInstruction> ops;
+
+    private void appendNew(int index, int count) {
+        indexAndCount.add(index);
+        indexAndCount.add(count);
+    }
+
+    private void setCountAt(int i, int value) {
+        indexAndCount.set((i << 1) + 1, value);
+    }
+
+    LIRInsertionBuffer() {
+        ops = new ArrayList<LIRInstruction>(8);
+        indexAndCount = new IntList(8);
+    }
+
+    // must be called before using the insertion buffer
+    void init(LIRList lir) {
+        assert !initialized() : "already initialized";
+        this.lir = lir;
+        indexAndCount.clear();
+        ops.clear();
+    }
+
+    boolean initialized() {
+        return lir != null;
+    }
+
+    // called automatically when the buffer is appended to the LIRList
+    public void finish() {
+        lir = null;
+    }
+
+    // accessors
+    public LIRList lirList() {
+        return lir;
+    }
+
+    public int numberOfInsertionPoints() {
+        return indexAndCount.size() >> 1;
+    }
+
+    public int indexAt(int i) {
+        return indexAndCount.get((i << 1));
+    }
+
+    public int countAt(int i) {
+        return indexAndCount.get((i << 1) + 1);
+    }
+
+    public int numberOfOps() {
+        return ops.size();
+    }
+
+    public LIRInstruction opAt(int i) {
+        return ops.get(i);
+    }
+
+    void move(int index, CiValue src, CiValue dst, LIRDebugInfo info) {
+        append(index, new LIROp1(LIROpcode.Move, src, dst, dst.kind, info));
+    }
+
+    // Implementation of LIRInsertionBuffer
+
+    private void append(int index, LIRInstruction op) {
+        assert indexAndCount.size() % 2 == 0 : "must have a count for each index";
+
+        int i = numberOfInsertionPoints() - 1;
+        if (i < 0 || indexAt(i) < index) {
+            appendNew(index, 1);
+        } else {
+            assert indexAt(i) == index : "can append LIROps in ascending order only";
+            assert countAt(i) > 0 : "check";
+            setCountAt(i, countAt(i) + 1);
+        }
+        ops.add(op);
+
+        assert verify();
+    }
+
+    private boolean verify() {
+        int sum = 0;
+        int prevIdx = -1;
+
+        for (int i = 0; i < numberOfInsertionPoints(); i++) {
+            assert prevIdx < indexAt(i) : "index must be ordered ascending";
+            sum += countAt(i);
+        }
+        assert sum == numberOfOps() : "wrong total sum";
+        return true;
+    }
+}