Preserve order of HPy debug handles

Author: fangerer

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/GraalHPyDebugModuleBuiltins.java

@@ -44,6 +44,7 @@
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.List;
 
 import com.oracle.graal.python.PythonLanguage;
@@ -132,7 +133,7 @@ PList doInt(VirtualFrame frame, int generation) {
         private static Object[] getOpenDebugHandles(GraalHPyDebugContext debugContext, int generation) {
             ArrayList<GraalHPyHandle> openHandles = debugContext.getOpenHandles(generation);
             int n = openHandles.size();
-            openHandles.sort((a, b) -> Integer.compare(debugContext.getGenerationForHandle(b), debugContext.getGenerationForHandle(a)));
+            openHandles.sort(Comparator.comparingLong(debugContext::getDebugHandleInfo));
             Object[] result = new Object[n];
             PythonObjectFactory factory = PythonObjectFactory.getUncached();
             // do reverse order to match order expected by HPy tests

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/hpy/GraalHPyDebugContext.java

@@ -48,7 +48,8 @@
 public final class GraalHPyDebugContext extends GraalHPyContext {
 
     private int currentGeneration;
-    private int[] generationTable = new int[]{0};
+    private int age;
+    private long[] debugHandleInfo = new long[]{0};
 
     public GraalHPyDebugContext(GraalHPyContext context) {
         super(context.getContext(), context.getLLVMLibrary());
@@ -62,7 +63,7 @@ public GraalHPyDebugContext(GraalHPyContext context) {
     /**
      * Since the initialization of the context members cannot use {@link #createHandle(Object)}, we
      * track the constants of the debug mode separately here. The reason why we can't use
-     * {@link #createHandle(Object)} is that the {@link #generationTable} will be initialized after
+     * {@link #createHandle(Object)} is that the {@link #debugHandleInfo} will be initialized after
      * the context members and that would cause an NPE.
      */
     private void trackConstants() {
@@ -81,8 +82,8 @@ protected String getName() {
     @TruffleBoundary
     public ArrayList<GraalHPyHandle> getOpenHandles(int generation) {
         ArrayList<GraalHPyHandle> openHandles = new ArrayList<>();
-        for (int i = 0; i < generationTable.length; i++) {
-            if (generationTable[i] >= generation) {
+        for (int i = 0; i < debugHandleInfo.length; i++) {
+            if (getGeneration(debugHandleInfo[i]) >= generation) {
                 openHandles.add(getObjectForHPyHandle(i));
             }
         }
@@ -93,21 +94,22 @@ public int getCurrentGeneration() {
         return currentGeneration;
     }
 
-    public int getGenerationForHandle(GraalHPyHandle handle) {
-        return generationTable[handle.getIdDebug(this)];
+    public long getDebugHandleInfo(GraalHPyHandle handle) {
+        return debugHandleInfo[handle.getIdDebug(this)];
     }
 
     public int newGeneration() {
+        age = 0;
         return ++currentGeneration;
     }
 
     private void trackHandle(GraalHPyHandle handle) {
         int id = handle.getIdDebug(this);
-        if (id >= generationTable.length) {
-            int newSize = Math.max(16, generationTable.length * 2);
-            generationTable = PythonUtils.arrayCopyOf(generationTable, newSize);
+        if (id >= debugHandleInfo.length) {
+            int newSize = Math.max(16, debugHandleInfo.length * 2);
+            debugHandleInfo = PythonUtils.arrayCopyOf(debugHandleInfo, newSize);
         }
-        generationTable[id] = currentGeneration;
+        debugHandleInfo[id] = toBits(currentGeneration, age++);
     }
 
     @Override
@@ -120,6 +122,14 @@ public GraalHPyHandle createHandle(Object delegate) {
     @Override
     public synchronized void releaseHPyHandleForObject(int handle) {
         super.releaseHPyHandleForObject(handle);
-        generationTable[handle] = -1;
+        debugHandleInfo[handle] = -1;
+    }
+
+    private static int getGeneration(long bits) {
+        return (int) (bits >>> Integer.SIZE);
+    }
+
+    private static long toBits(int generation, int age) {
+        return ((long) generation << Integer.SIZE) | age;
     }
 }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/util/PythonUtils.java

@@ -189,6 +189,19 @@ public static int[] arrayCopyOf(int[] original, int newLength) {
         }
     }
 
+    /**
+     * Executes {@link Arrays#copyOf(long[], int)} and puts all exceptions on the slow path.
+     */
+    public static long[] arrayCopyOf(long[] original, int newLength) {
+        try {
+            return Arrays.copyOf(original, newLength);
+        } catch (Throwable t) {
+            // Break exception edges
+            CompilerDirectives.transferToInterpreterAndInvalidate();
+            throw t;
+        }
+    }
+
     /**
      * Executes {@code String.getChars} and puts all exceptions on the slow path.
      */