--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/opto/stringopts.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2009, 2015, 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.
+ *
+ */
+
+#ifndef SHARE_VM_OPTO_STRINGOPTS_HPP
+#define SHARE_VM_OPTO_STRINGOPTS_HPP
+
+#include "opto/node.hpp"
+#include "opto/phaseX.hpp"
+
+class StringConcat;
+class IdealVariable;
+
+class PhaseStringOpts : public Phase {
+  friend class StringConcat;
+
+ private:
+  PhaseGVN* _gvn;
+
+  // List of dead nodes to clean up aggressively at the end
+  Unique_Node_List dead_worklist;
+
+  // Memory slices needed for code gen
+  int byte_adr_idx;
+
+  // Integer.sizeTable - used for int to String conversion
+  ciField* size_table_field;
+
+  // A set for use by various stages
+  VectorSet _visited;
+
+  // Collect a list of all SB.toString calls
+  Node_List collect_toString_calls();
+
+  // Examine the use of the SB alloc to see if it can be replace with
+  // a single string construction.
+  StringConcat* build_candidate(CallStaticJavaNode* call);
+
+  // Replace all the SB calls in concat with an optimization String allocation
+  void replace_string_concat(StringConcat* concat);
+
+  // Load the value of a static field, performing any constant folding.
+  Node* fetch_static_field(GraphKit& kit, ciField* field);
+
+  // Compute the number of characters required to represent the int value
+  Node* int_stringSize(GraphKit& kit, Node* value);
+
+  // Simplified version of Integer.getChars
+  void getChars(GraphKit& kit, Node* arg, Node* dst_array, BasicType bt, Node* end, Node* final_merge, Node* final_mem, int merge_index = 0);
+
+  // Copy the characters representing arg into dst_array starting at start
+  Node* int_getChars(GraphKit& kit, Node* arg, Node* dst_array, Node* dst_coder, Node* start, Node* size);
+
+  // Copy contents of the String str into dst_array starting at index start.
+  Node* copy_string(GraphKit& kit, Node* str, Node* dst_array, Node* dst_coder, Node* start);
+
+  // Copy 'count' bytes/chars from src_array to dst_array starting at index start
+  void arraycopy(GraphKit& kit, IdealKit& ideal, Node* src_array, Node* dst_array, BasicType elembt, Node* start, Node* count);
+
+  // Copy contents of constant src_array to dst_array by emitting individual stores
+  void copy_constant_string(GraphKit& kit, IdealKit& ideal, ciTypeArray* src_array, IdealVariable& count,
+                            bool src_is_byte, Node* dst_array, Node* dst_coder, Node* start);
+
+  // Copy contents of a Latin1 encoded string from src_array to dst_array
+  void copy_latin1_string(GraphKit& kit, IdealKit& ideal, Node* src_array, IdealVariable& count,
+                          Node* dst_array, Node* dst_coder, Node* start);
+
+  // Copy the char into dst_array at index start.
+  Node* copy_char(GraphKit& kit, Node* val, Node* dst_array, Node* dst_coder, Node* start);
+
+  // Allocate a byte array of specified length.
+  Node* allocate_byte_array(GraphKit& kit, IdealKit* ideal, Node* length);
+
+  // Returns the coder of a constant string
+  jbyte get_constant_coder(GraphKit& kit, Node* str);
+
+  // Returns the length of a constant string
+  int get_constant_length(GraphKit& kit, Node* str);
+
+  // Returns the value array of a constant string
+  ciTypeArray* get_constant_value(GraphKit& kit, Node* str);
+
+  // Clean up any leftover nodes
+  void record_dead_node(Node* node);
+  void remove_dead_nodes();
+
+  PhaseGVN* gvn() { return _gvn; }
+
+  enum {
+    // max length of constant string copy unrolling in copy_string
+    unroll_string_copy_length = 6
+  };
+
+ public:
+  PhaseStringOpts(PhaseGVN* gvn, Unique_Node_List* worklist);
+};
+
+#endif // SHARE_VM_OPTO_STRINGOPTS_HPP