[GR-13916] avoid the storage switch for dict literal nodes when not all keys are strings

PullRequest: graalpython/433

Author: cosminbasca

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/literal/DictLiteralNode.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2018, Oracle and/or its affiliates.
+ * Copyright (c) 2017, 2019, Oracle and/or its affiliates.
  * Copyright (c) 2013, Regents of the University of California
  *
  * All rights reserved.
@@ -49,20 +49,50 @@ public DictLiteralNode(ExpressionNode[] keys, ExpressionNode[] values) {
         assert keys.length == values.length;
     }
 
-    @Override
+    static final class Keys {
+        public final Object[] keys;
+        public final boolean allStrings;
+
+        Keys(Object[] keys, boolean allStrings) {
+            this.keys = keys;
+            this.allStrings = allStrings;
+        }
+    }
+
     @ExplodeLoop
-    public PDict execute(VirtualFrame frame) {
-        HashingStorage dictStorage = PDict.createNewStorage(true, values.length);
+    private Keys evalKeys(VirtualFrame frame) {
+        boolean allStrings = true;
+        Object[] evalKeys = new Object[this.keys.length];
+        for (int i = 0; i < values.length; i++) {
+            evalKeys[i] = keys[i].execute(frame);
+            if (!(evalKeys[i] instanceof String)) {
+                allStrings = false;
+            }
+        }
+        return new Keys(evalKeys, allStrings);
+    }
+
+    @ExplodeLoop
+    private HashingStorage evalAndSetValues(VirtualFrame frame, HashingStorage dictStorage, Keys evalKeys) {
+        HashingStorage storage = dictStorage;
         for (int i = 0; i < values.length; i++) {
-            final Object key = keys[i].execute(frame);
             final Object val = values[i].execute(frame);
 
             if (setItemNode == null) {
                 CompilerDirectives.transferToInterpreterAndInvalidate();
                 setItemNode = insert(SetItemNode.create());
             }
-            dictStorage = setItemNode.execute(dictStorage, key, val);
+
+            storage = setItemNode.execute(storage, evalKeys.keys[i], val);
         }
+        return storage;
+    }
+
+    @Override
+    public PDict execute(VirtualFrame frame) {
+        Keys evalKeys = evalKeys(frame);
+        HashingStorage dictStorage = PDict.createNewStorage(evalKeys.allStrings, evalKeys.keys.length);
+        dictStorage = evalAndSetValues(frame, dictStorage, evalKeys);
         return factory().createDict(dictStorage);
     }
 }