[Truffle] Implemented the string_substring primitive for rope buffers.

jruby · Apr 12, 2016 · cbc3631 · eregon · Apr 13, 2016 · nirvdrum
1 parent ff7bdcf
commit cbc3631
Showing 1 changed file with 35 additions and 1 deletion.
diff --git a/truffle/src/main/java/org/jruby/truffle/core/rubinius/StringPrimitiveNodes.java b/truffle/src/main/java/org/jruby/truffle/core/rubinius/StringPrimitiveNodes.java
@@ -89,6 +89,7 @@
 import org.jruby.truffle.core.rope.CodeRange;
 import org.jruby.truffle.core.rope.RepeatingRope;
 import org.jruby.truffle.core.rope.Rope;
+import org.jruby.truffle.core.rope.RopeBuffer;
 import org.jruby.truffle.core.rope.RopeConstants;
 import org.jruby.truffle.core.rope.RopeNodes;
 import org.jruby.truffle.core.rope.RopeNodesFactory;
@@ -1655,7 +1656,8 @@ public Object stringSubstring(DynamicObject string, int beg, int len,
                                                            @Cached("createBinaryProfile()") ConditionProfile negativeBeginProfile,
                                                            @Cached("createBinaryProfile()") ConditionProfile stillNegativeBeginProfile,
                                                            @Cached("createBinaryProfile()") ConditionProfile tooLargeTotalProfile,
-                                                           @Cached("createBinaryProfile()") ConditionProfile negativeLengthProfile) {
+                                                           @Cached("createBinaryProfile()") ConditionProfile negativeLengthProfile,
+                                                           @Cached("createBinaryProfile()") ConditionProfile mutableRopeProfile) {
             // Taken from org.jruby.RubyString#substr19.
             final Rope rope = rope(string);
             if (emptyStringProfile.profile(rope.isEmpty())) {
@@ -1684,6 +1686,10 @@ public Object stringSubstring(DynamicObject string, int beg, int len,
                 beg = 0;
             }
 
+            if (mutableRopeProfile.profile(rope instanceof RopeBuffer)) {
+                return makeBuffer(string, beg, len);
+            }
+
             return makeRope(string, beg, len);
         }
 
@@ -1790,6 +1796,34 @@ private DynamicObject makeRope(DynamicObject string, int beg, int len) {
             return ret;
         }
 
+        private DynamicObject makeBuffer(DynamicObject string, int beg, int len) {
+            assert RubyGuards.isRubyString(string);
+
+            final RopeBuffer buffer = (RopeBuffer) rope(string);
+
+            if (allocateNode == null) {
+                CompilerDirectives.transferToInterpreter();
+                allocateNode = insert(AllocateObjectNodeGen.create(getContext(), getSourceSection(), null, null));
+            }
+
+            if (taintResultNode == null) {
+                CompilerDirectives.transferToInterpreter();
+                taintResultNode = insert(new TaintResultNode(getContext(), getSourceSection()));
+            }
+
+            // NB: This is only valid for the single-byte case. If multi-byte, the code range must be recalculated.
+            // This is not intended to be a 100% correct implementation, since you should normally be using the
+            // immutable rope variant.
+            final DynamicObject ret = allocateNode.allocate(
+                    Layouts.BASIC_OBJECT.getLogicalClass(string),
+                    new RopeBuffer(new ByteList(buffer.getByteList(), beg, len), buffer.getCodeRange(), buffer.isSingleByteOptimizable(), len),
+                    null);
+
+            taintResultNode.maybeTaint(string, ret);
+
+            return ret;
+        }
+
     }
 
     @RubiniusPrimitive(name = "string_from_bytearray", needsSelf = false, lowerFixnumParameters = { 1, 2 })