fix concatenation and generalization of empty ListStorage list

Author: timfel

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/common/SequenceStorageNodes.java

@@ -2012,6 +2012,7 @@ private SequenceStorage createEmpty(SequenceStorage l, SequenceStorage r, int le
                 return createEmptyNode.execute(r, len);
             }
             SequenceStorage empty = createEmptyNode.execute(l, len);
+            empty.ensureCapacity(len);
             empty.setNewLength(len);
             return empty;
         }
@@ -2427,8 +2428,8 @@ DoubleSequenceStorage doEmptyDouble(@SuppressWarnings("unused") EmptySequenceSto
         }
 
         @Specialization
-        ListSequenceStorage doEmptyPList(@SuppressWarnings("unused") EmptySequenceStorage s, PList val) {
-            return new ListSequenceStorage(val.getSequenceStorage());
+        ListSequenceStorage doEmptyPList(@SuppressWarnings("unused") EmptySequenceStorage s, @SuppressWarnings("unused") PList val) {
+            return new ListSequenceStorage(0);
         }
 
         @Specialization
@@ -2623,9 +2624,9 @@ DoubleSequenceStorage doDouble(@SuppressWarnings("unused") SequenceStorage s, in
         }
 
         @Specialization(guards = "isList(s)")
-        ListSequenceStorage doList(@SuppressWarnings("unused") SequenceStorage s, @SuppressWarnings("unused") int cap) {
+        ListSequenceStorage doList(@SuppressWarnings("unused") SequenceStorage s, int cap) {
             // TODO not quite accurate in case of native sequence storage
-            return new ListSequenceStorage(s);
+            return new ListSequenceStorage(cap);
         }
 
         @Specialization(guards = "isTuple(s)")

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/sequence/storage/EmptySequenceStorage.java

@@ -57,7 +57,7 @@ public SequenceStorage generalizeFor(Object value, SequenceStorage target) {
         } else if (value instanceof Double) {
             generalized = new DoubleSequenceStorage();
         } else if (value instanceof PList) {
-            generalized = new ListSequenceStorage(((PList) value).getSequenceStorage());
+            generalized = new ListSequenceStorage(0);
         } else if (value instanceof PTuple) {
             generalized = new TupleSequenceStorage();
         } else {

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/sequence/storage/ListSequenceStorage.java

@@ -32,49 +32,23 @@
 public final class ListSequenceStorage extends TypedSequenceStorage {
 
     private PList[] values;
-    private Class<?> kind;
-
-    public ListSequenceStorage(SequenceStorage elementSample) {
-        values = new PList[]{};
-        if (elementSample instanceof ListSequenceStorage) {
-            ListSequenceStorage list = (ListSequenceStorage) elementSample;
-            this.kind = list.getKind();
-        } else {
-            this.kind = elementSample.getClass();
-        }
-    }
 
     public ListSequenceStorage(PList[] elements) {
-        this(elements, elements[0].getSequenceStorage().getClass());
-        if (kind == ListSequenceStorage.class)
-            this.kind = ((ListSequenceStorage) elements[0].getSequenceStorage()).getKind();
-    }
-
-    public ListSequenceStorage(PList[] elements, int length) {
-        this(elements, elements[0].getSequenceStorage().getClass(), length);
-        if (kind == ListSequenceStorage.class)
-            this.kind = ((ListSequenceStorage) elements[0].getSequenceStorage()).getKind();
-    }
-
-    public ListSequenceStorage(PList[] elements, Class<?> kind) {
         this.values = elements;
         capacity = values.length;
         length = elements.length;
-        this.kind = kind;
     }
 
-    public ListSequenceStorage(PList[] elements, Class<?> kind, int length) {
+    public ListSequenceStorage(PList[] elements, int length) {
         this.values = elements;
         capacity = values.length;
         this.length = length;
-        this.kind = kind;
     }
 
-    public ListSequenceStorage(int capacity, Class<?> kind) {
+    public ListSequenceStorage(int capacity) {
         this.values = new PList[capacity];
         this.capacity = capacity;
         length = 0;
-        this.kind = kind;
     }
 
     @Override
@@ -91,16 +65,12 @@ protected void increaseCapacityExact(int newCapacity) {
 
     @Override
     public SequenceStorage copy() {
-        return new ListSequenceStorage(Arrays.copyOf(values, length), this.kind);
+        return new ListSequenceStorage(Arrays.copyOf(values, length));
     }
 
     @Override
     public SequenceStorage createEmpty(int newCapacity) {
-        return new ListSequenceStorage(newCapacity, this.kind);
-    }
-
-    public Class<?> getKind() {
-        return kind;
+        return new ListSequenceStorage(newCapacity);
     }
 
     @Override
@@ -175,14 +145,14 @@ public SequenceStorage getSliceInBound(int start, int stop, int step, int sliceL
 
         if (step == 1) {
             System.arraycopy(values, start, newArray, 0, sliceLength);
-            return new ListSequenceStorage(newArray, this.kind);
+            return new ListSequenceStorage(newArray);
         }
 
         for (int i = start, j = 0; j < sliceLength; i += step, j++) {
             newArray[j] = values[i];
         }
 
-        return new ListSequenceStorage(newArray, this.kind);
+        return new ListSequenceStorage(newArray);
     }
 
     public void setListSliceInBound(int start, int stop, int step, ListSequenceStorage sequence) {