1/*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
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24
25#ifndef SHARE_OPTO_COALESCE_HPP
26#define SHARE_OPTO_COALESCE_HPP
27
28#include "opto/phase.hpp"
29
30class LoopTree;
31class LRG;
32class Matcher;
33class PhaseIFG;
34class PhaseCFG;
35
36//------------------------------PhaseCoalesce----------------------------------
37class PhaseCoalesce : public Phase {
38protected:
39 PhaseChaitin &_phc;
40
41public:
42 // Coalesce copies
43 PhaseCoalesce(PhaseChaitin &phc)
44 : Phase(Coalesce)
45 , _phc(phc) {}
46
47 virtual void verify() = 0;
48
49 // Coalesce copies
50 void coalesce_driver();
51
52 // Coalesce copies in this block
53 virtual void coalesce(Block *b) = 0;
54
55 // Attempt to coalesce live ranges defined by these 2
56 void combine_these_two(Node *n1, Node *n2);
57
58 LRG &lrgs(uint lidx) { return _phc.lrgs(lidx); }
59#ifndef PRODUCT
60 // Dump internally name
61 void dump(Node *n) const;
62 // Dump whole shebang
63 void dump() const;
64#endif
65};
66
67//------------------------------PhaseAggressiveCoalesce------------------------
68// Aggressively, pessimistic coalesce copies. Aggressive means ignore graph
69// colorability; perhaps coalescing to the point of forcing a spill.
70// Pessimistic means we cannot coalesce if 2 live ranges interfere. This
71// implies we do not hit a fixed point right away.
72class PhaseAggressiveCoalesce : public PhaseCoalesce {
73 uint _unique;
74public:
75 // Coalesce copies
76 PhaseAggressiveCoalesce( PhaseChaitin &chaitin ) : PhaseCoalesce(chaitin) {}
77
78 virtual void verify() { };
79
80 // Aggressively coalesce copies in this block
81 virtual void coalesce( Block *b );
82
83 // Where I fail to coalesce, manifest virtual copies as the Real Thing
84 void insert_copies( Matcher &matcher );
85
86 // Copy insertion needs some smarts in case live ranges overlap
87 void insert_copy_with_overlap( Block *b, Node *copy, uint dst_name, uint src_name );
88};
89
90
91//------------------------------PhaseConservativeCoalesce----------------------
92// Conservatively, pessimistic coalesce copies. Conservative means do not
93// coalesce if the resultant live range will be uncolorable. Pessimistic
94// means we cannot coalesce if 2 live ranges interfere. This implies we do
95// not hit a fixed point right away.
96class PhaseConservativeCoalesce : public PhaseCoalesce {
97 IndexSet _ulr; // Union live range interferences
98public:
99 // Coalesce copies
100 PhaseConservativeCoalesce( PhaseChaitin &chaitin );
101
102 virtual void verify();
103
104 // Conservatively coalesce copies in this block
105 virtual void coalesce( Block *b );
106
107 // Coalesce this chain of copies away
108 bool copy_copy( Node *dst_copy, Node *src_copy, Block *b, uint bindex );
109
110 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 );
111
112 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);
113
114 void update_ifg(uint lr1, uint lr2, IndexSet *n_lr1, IndexSet *n_lr2);
115};
116
117#endif // SHARE_OPTO_COALESCE_HPP
118