1 /* 2 * Copyright (c) 2014, 2019, 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_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. 34 class Opaque1Node : public Node { 35 virtual uint hash() const ; // { return NO_HASH; } 36 virtual bool cmp( const Node &n ) const; 37 public: Opaque1Node(Compile * C,Node * n)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 init_class_id(Class_Opaque1); 42 C->add_macro_node(this); 43 } 44 // Special version for the pre-loop to hold the original loop limit 45 // which is consumed by range check elimination. Opaque1Node(Compile * C,Node * n,Node * orig_limit)46 Opaque1Node(Compile* C, Node *n, Node* orig_limit) : Node(NULL, n, orig_limit) { 47 // Put it on the Macro nodes list to removed during macro nodes expansion. 48 init_flags(Flag_is_macro); 49 init_class_id(Class_Opaque1); 50 C->add_macro_node(this); 51 } original_loop_limit()52 Node* original_loop_limit() { return req()==3 ? in(2) : NULL; } 53 virtual int Opcode() const; bottom_type() const54 virtual const Type *bottom_type() const { return TypeInt::INT; } 55 virtual Node* Identity(PhaseGVN* phase); 56 }; 57 58 // Opaque nodes specific to range check elimination handling 59 class OpaqueLoopInitNode : public Opaque1Node { 60 public: OpaqueLoopInitNode(Compile * C,Node * n)61 OpaqueLoopInitNode(Compile* C, Node *n) : Opaque1Node(C, n) { 62 } 63 virtual int Opcode() const; 64 }; 65 66 class OpaqueLoopStrideNode : public Opaque1Node { 67 public: OpaqueLoopStrideNode(Compile * C,Node * n)68 OpaqueLoopStrideNode(Compile* C, Node *n) : Opaque1Node(C, n) { 69 } 70 virtual int Opcode() const; 71 }; 72 73 //------------------------------Opaque2Node------------------------------------ 74 // A node to prevent unwanted optimizations. Allows constant folding. Stops 75 // value-numbering, most Ideal calls or Identity functions. This Node is 76 // specifically designed to prevent the pre-increment value of a loop trip 77 // counter from being live out of the bottom of the loop (hence causing the 78 // pre- and post-increment values both being live and thus requiring an extra 79 // temp register and an extra move). If we "accidentally" optimize through 80 // this kind of a Node, we'll get slightly pessimal, but correct, code. Thus 81 // it's OK to be slightly sloppy on optimizations here. 82 class Opaque2Node : public Node { 83 virtual uint hash() const ; // { return NO_HASH; } 84 virtual bool cmp( const Node &n ) const; 85 public: Opaque2Node(Compile * C,Node * n)86 Opaque2Node( Compile* C, Node *n ) : Node(0,n) { 87 // Put it on the Macro nodes list to removed during macro nodes expansion. 88 init_flags(Flag_is_macro); 89 C->add_macro_node(this); 90 } 91 virtual int Opcode() const; bottom_type() const92 virtual const Type *bottom_type() const { return TypeInt::INT; } 93 }; 94 95 //------------------------------Opaque3Node------------------------------------ 96 // A node to prevent unwanted optimizations. Will be optimized only during 97 // macro nodes expansion. 98 class Opaque3Node : public Opaque2Node { 99 int _opt; // what optimization it was used for 100 public: 101 enum { RTM_OPT }; Opaque3Node(Compile * C,Node * n,int opt)102 Opaque3Node(Compile* C, Node *n, int opt) : Opaque2Node(C, n), _opt(opt) {} 103 virtual int Opcode() const; rtm_opt() const104 bool rtm_opt() const { return (_opt == RTM_OPT); } 105 }; 106 107 // Input 1 is a check that we know implicitly is always true or false 108 // but the compiler has no way to prove. If during optimizations, that 109 // check becomes true or false, the Opaque4 node is replaced by that 110 // constant true or false. Input 2 is the constant value we know the 111 // test takes. After loop optimizations, we replace input 1 by input 2 112 // so the control that depends on that test can be removed and there's 113 // no overhead at runtime. Used for instance by 114 // GraphKit::must_be_not_null(). 115 class Opaque4Node : public Node { 116 public: Opaque4Node(Compile * C,Node * tst,Node * final_tst)117 Opaque4Node(Compile* C, Node *tst, Node* final_tst) : Node(NULL, tst, final_tst) {} 118 119 virtual int Opcode() const; bottom_type() const120 virtual const Type *bottom_type() const { return TypeInt::BOOL; } 121 virtual Node* Identity(PhaseGVN* phase); 122 virtual const Type* Value(PhaseGVN* phase) const; 123 }; 124 125 126 //------------------------------ProfileBooleanNode------------------------------- 127 // A node represents value profile for a boolean during parsing. 128 // Once parsing is over, the node goes away (during IGVN). 129 // It is used to override branch frequencies from MDO (see has_injected_profile in parse2.cpp). 130 class ProfileBooleanNode : public Node { 131 uint _false_cnt; 132 uint _true_cnt; 133 bool _consumed; 134 bool _delay_removal; 135 virtual uint hash() const ; // { return NO_HASH; } 136 virtual bool cmp( const Node &n ) const; 137 public: ProfileBooleanNode(Node * n,uint false_cnt,uint true_cnt)138 ProfileBooleanNode(Node *n, uint false_cnt, uint true_cnt) : Node(0, n), 139 _false_cnt(false_cnt), _true_cnt(true_cnt), _consumed(false), _delay_removal(true) {} 140 false_count() const141 uint false_count() const { return _false_cnt; } true_count() const142 uint true_count() const { return _true_cnt; } 143 consume()144 void consume() { _consumed = true; } 145 146 virtual int Opcode() const; 147 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape); 148 virtual Node* Identity(PhaseGVN* phase); bottom_type() const149 virtual const Type *bottom_type() const { return TypeInt::BOOL; } 150 }; 151 152 #endif // SHARE_OPTO_OPAQUENODE_HPP 153