1 /* 2 * Copyright (c) 1997, 2010, 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_COALESCE_HPP 26 #define SHARE_VM_OPTO_COALESCE_HPP 27 28 #include "opto/phase.hpp" 29 30 class LoopTree; 31 class LRG; 32 class LRG_List; 33 class Matcher; 34 class PhaseIFG; 35 class PhaseCFG; 36 37 //------------------------------PhaseCoalesce---------------------------------- 38 class PhaseCoalesce : public Phase { 39 protected: 40 PhaseChaitin &_phc; 41 42 public: 43 // Coalesce copies 44 PhaseCoalesce( PhaseChaitin &chaitin ) : Phase(Coalesce), _phc(chaitin) { } 45 46 virtual void verify() = 0; 47 48 // Coalesce copies 49 void coalesce_driver( ); 50 51 // Coalesce copies in this block 52 virtual void coalesce( Block *b ) = 0; 53 54 // Attempt to coalesce live ranges defined by these 2 55 void combine_these_two( Node *n1, Node *n2 ); 56 57 LRG &lrgs( uint lidx ) { return _phc.lrgs(lidx); } 58 #ifndef PRODUCT 59 // Dump internally name 60 void dump( Node *n ) const; 61 // Dump whole shebang 62 void dump() const; 63 #endif 64 }; 65 66 //------------------------------PhaseAggressiveCoalesce------------------------ 67 // Aggressively, pessimistic coalesce copies. Aggressive means ignore graph 68 // colorability; perhaps coalescing to the point of forcing a spill. 69 // Pessimistic means we cannot coalesce if 2 live ranges interfere. This 70 // implies we do not hit a fixed point right away. 71 class PhaseAggressiveCoalesce : public PhaseCoalesce { 72 uint _unique; 73 public: 74 // Coalesce copies 75 PhaseAggressiveCoalesce( PhaseChaitin &chaitin ) : PhaseCoalesce(chaitin) {} 76 77 virtual void verify() { }; 78 79 // Aggressively coalesce copies in this block 80 virtual void coalesce( Block *b ); 81 82 // Where I fail to coalesce, manifest virtual copies as the Real Thing 83 void insert_copies( Matcher &matcher ); 84 85 // Copy insertion needs some smarts in case live ranges overlap 86 void insert_copy_with_overlap( Block *b, Node *copy, uint dst_name, uint src_name ); 87 }; 88 89 90 //------------------------------PhaseConservativeCoalesce---------------------- 91 // Conservatively, pessimistic coalesce copies. Conservative means do not 92 // coalesce if the resultant live range will be uncolorable. Pessimistic 93 // means we cannot coalesce if 2 live ranges interfere. This implies we do 94 // not hit a fixed point right away. 95 class PhaseConservativeCoalesce : public PhaseCoalesce { 96 IndexSet _ulr; // Union live range interferences 97 public: 98 // Coalesce copies 99 PhaseConservativeCoalesce( PhaseChaitin &chaitin ); 100 101 virtual void verify(); 102 103 // Conservatively coalesce copies in this block 104 virtual void coalesce( Block *b ); 105 106 // Coalesce this chain of copies away 107 bool copy_copy( Node *dst_copy, Node *src_copy, Block *b, uint bindex ); 108 109 void union_helper( Node *lr1_node, Node *lr2_node, uint lr1, uint lr2, Node *src_def, Node *dst_copy, Node *src_copy, Block *b, uint bindex ); 110 111 uint compute_separating_interferences(Node *dst_copy, Node *src_copy, Block *b, uint bindex, RegMask &rm, uint rm_size, uint reg_degree, uint lr1, uint lr2); 112 113 void update_ifg(uint lr1, uint lr2, IndexSet *n_lr1, IndexSet *n_lr2); 114 }; 115 116 #endif // SHARE_VM_OPTO_COALESCE_HPP