1 /* 2 * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_OPTO_STRINGOPTS_HPP 26 #define SHARE_VM_OPTO_STRINGOPTS_HPP 27 28 #include "opto/node.hpp" 29 #include "opto/phaseX.hpp" 30 31 class StringConcat; 32 33 class PhaseStringOpts : public Phase { 34 friend class StringConcat; 35 36 private: 37 PhaseGVN* _gvn; 38 39 // List of dead nodes to clean up aggressively at the end 40 Unique_Node_List dead_worklist; 41 42 // Memory slices needed for code gen 43 int char_adr_idx; 44 45 // Integer.sizeTable - used for int to String conversion 46 ciField* size_table_field; 47 48 // A set for use by various stages 49 VectorSet _visited; 50 51 // Stack for doing DFS in memory flow analysis 52 Node_Stack _path; 53 54 // Collect a list of all SB.toString calls 55 Node_List collect_toString_calls(); 56 57 // Examine the use of the SB alloc to see if it can be replace with 58 // a single string construction. 59 StringConcat* build_candidate(CallStaticJavaNode* call); 60 61 // Replace all the SB calls in concat with an optimization String allocation 62 void replace_string_concat(StringConcat* concat); 63 64 // Load the value of a static field, performing any constant folding. 65 Node* fetch_static_field(GraphKit& kit, ciField* field); 66 67 // Compute the number of characters required to represent the int value 68 Node* int_stringSize(GraphKit& kit, Node* value); 69 70 // Copy the characters representing value into char_array starting at start 71 void int_getChars(GraphKit& kit, Node* value, Node* char_array, Node* start, Node* end); 72 73 // Copy of the contents of the String str into char_array starting at index start. 74 Node* copy_string(GraphKit& kit, Node* str, Node* char_array, Node* start); 75 76 // Clean up any leftover nodes 77 void record_dead_node(Node* node); 78 void remove_dead_nodes(); 79 80 PhaseGVN* gvn() { return _gvn; } 81 82 enum { 83 // max length of constant string copy unrolling in copy_string 84 unroll_string_copy_length = 6, 85 memory_flow_iteration_limit = 99 86 }; 87 88 public: 89 PhaseStringOpts(PhaseGVN* gvn, Unique_Node_List* worklist); 90 }; 91 92 #endif // SHARE_VM_OPTO_STRINGOPTS_HPP