stringopts.hpp revision 1472:c18cbe5936b8 
1/*
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24
25class StringConcat;
26
27class PhaseStringOpts : public Phase {
28  friend class StringConcat;
29
30 private:
31  PhaseGVN* _gvn;
32
33  // List of dead nodes to clean up aggressively at the end
34  Unique_Node_List dead_worklist;
35
36  // Memory slices needed for code gen
37  int char_adr_idx;
38  int value_field_idx;
39  int count_field_idx;
40  int offset_field_idx;
41
42  // Integer.sizeTable - used for int to String conversion
43  ciField* size_table_field;
44
45  // A set for use by various stages
46  VectorSet _visited;
47
48  // Collect a list of all SB.toString calls
49  Node_List collect_toString_calls();
50
51  // Examine the use of the SB alloc to see if it can be replace with
52  // a single string construction.
53  StringConcat* build_candidate(CallStaticJavaNode* call);
54
55  // Replace all the SB calls in concat with an optimization String allocation
56  void replace_string_concat(StringConcat* concat);
57
58  // Load the value of a static field, performing any constant folding.
59  Node* fetch_static_field(GraphKit& kit, ciField* field);
60
61  // Compute the number of characters required to represent the int value
62  Node* int_stringSize(GraphKit& kit, Node* value);
63
64  // Copy the characters representing value into char_array starting at start
65  void int_getChars(GraphKit& kit, Node* value, Node* char_array, Node* start, Node* end);
66
67  // Copy of the contents of the String str into char_array starting at index start.
68  Node* copy_string(GraphKit& kit, Node* str, Node* char_array, Node* start);
69
70  // Clean up any leftover nodes
71  void record_dead_node(Node* node);
72  void remove_dead_nodes();
73
74  PhaseGVN* gvn() { return _gvn; }
75
76  enum {
77    // max length of constant string copy unrolling in copy_string
78    unroll_string_copy_length = 6
79  };
80
81 public:
82  PhaseStringOpts(PhaseGVN* gvn, Unique_Node_List* worklist);
83};
84