1/*
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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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24
25#ifndef SHARE_OPTO_OPAQUENODE_HPP
26#define SHARE_OPTO_OPAQUENODE_HPP
27
28#include "opto/node.hpp"
29#include "opto/opcodes.hpp"
30
31//------------------------------Opaque1Node------------------------------------
32// A node to prevent unwanted optimizations. Allows constant folding.
33// Stops value-numbering, Ideal calls or Identity functions.
34class Opaque1Node : public Node {
35 virtual uint hash() const ; // { return NO_HASH; }
36 virtual bool cmp( const Node &n ) const;
37 public:
38 Opaque1Node(Compile* C, Node *n) : Node(NULL, n) {
39 // Put it on the Macro nodes list to removed during macro nodes expansion.
40 init_flags(Flag_is_macro);
41 C->add_macro_node(this);
42 }
43 // Special version for the pre-loop to hold the original loop limit
44 // which is consumed by range check elimination.
45 Opaque1Node(Compile* C, Node *n, Node* orig_limit) : Node(NULL, n, orig_limit) {
46 // Put it on the Macro nodes list to removed during macro nodes expansion.
47 init_flags(Flag_is_macro);
48 C->add_macro_node(this);
49 }
50 Node* original_loop_limit() { return req()==3 ? in(2) : NULL; }
51 virtual int Opcode() const;
52 virtual const Type *bottom_type() const { return TypeInt::INT; }
53 virtual Node* Identity(PhaseGVN* phase);
54};
55
56//------------------------------Opaque2Node------------------------------------
57// A node to prevent unwanted optimizations. Allows constant folding. Stops
58// value-numbering, most Ideal calls or Identity functions. This Node is
59// specifically designed to prevent the pre-increment value of a loop trip
60// counter from being live out of the bottom of the loop (hence causing the
61// pre- and post-increment values both being live and thus requiring an extra
62// temp register and an extra move). If we "accidentally" optimize through
63// this kind of a Node, we'll get slightly pessimal, but correct, code. Thus
64// it's OK to be slightly sloppy on optimizations here.
65class Opaque2Node : public Node {
66 virtual uint hash() const ; // { return NO_HASH; }
67 virtual bool cmp( const Node &n ) const;
68 public:
69 Opaque2Node( Compile* C, Node *n ) : Node(0,n) {
70 // Put it on the Macro nodes list to removed during macro nodes expansion.
71 init_flags(Flag_is_macro);
72 C->add_macro_node(this);
73 }
74 virtual int Opcode() const;
75 virtual const Type *bottom_type() const { return TypeInt::INT; }
76};
77
78//------------------------------Opaque3Node------------------------------------
79// A node to prevent unwanted optimizations. Will be optimized only during
80// macro nodes expansion.
81class Opaque3Node : public Opaque2Node {
82 int _opt; // what optimization it was used for
83 public:
84 enum { RTM_OPT };
85 Opaque3Node(Compile* C, Node *n, int opt) : Opaque2Node(C, n), _opt(opt) {}
86 virtual int Opcode() const;
87 bool rtm_opt() const { return (_opt == RTM_OPT); }
88};
89
90// Input 1 is a check that we know implicitly is always true or false
91// but the compiler has no way to prove. If during optimizations, that
92// check becomes true or false, the Opaque4 node is replaced by that
93// constant true or false. Input 2 is the constant value we know the
94// test takes. After loop optimizations, we replace input 1 by input 2
95// so the control that depends on that test can be removed and there's
96// no overhead at runtime. Used for instance by
97// GraphKit::must_be_not_null().
98class Opaque4Node : public Node {
99 public:
100 Opaque4Node(Compile* C, Node *tst, Node* final_tst) : Node(NULL, tst, final_tst) {
101 // Put it on the Opaque4 nodes list to be removed after all optimizations
102 C->add_opaque4_node(this);
103 }
104 virtual int Opcode() const;
105 virtual const Type *bottom_type() const { return TypeInt::BOOL; }
106 virtual const Type* Value(PhaseGVN* phase) const;
107};
108
109
110//------------------------------ProfileBooleanNode-------------------------------
111// A node represents value profile for a boolean during parsing.
112// Once parsing is over, the node goes away (during IGVN).
113// It is used to override branch frequencies from MDO (see has_injected_profile in parse2.cpp).
114class ProfileBooleanNode : public Node {
115 uint _false_cnt;
116 uint _true_cnt;
117 bool _consumed;
118 bool _delay_removal;
119 virtual uint hash() const ; // { return NO_HASH; }
120 virtual bool cmp( const Node &n ) const;
121 public:
122 ProfileBooleanNode(Node *n, uint false_cnt, uint true_cnt) : Node(0, n),
123 _false_cnt(false_cnt), _true_cnt(true_cnt), _consumed(false), _delay_removal(true) {}
124
125 uint false_count() const { return _false_cnt; }
126 uint true_count() const { return _true_cnt; }
127
128 void consume() { _consumed = true; }
129
130 virtual int Opcode() const;
131 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
132 virtual Node* Identity(PhaseGVN* phase);
133 virtual const Type *bottom_type() const { return TypeInt::BOOL; }
134};
135
136#endif // SHARE_OPTO_OPAQUENODE_HPP
137