1// Copyright 2014 the V8 project authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef V8_COMPILER_MACHINE_OPERATOR_REDUCER_H_
6#define V8_COMPILER_MACHINE_OPERATOR_REDUCER_H_
7
8#include "src/base/compiler-specific.h"
9#include "src/common/globals.h"
10#include "src/compiler/graph-reducer.h"
11#include "src/compiler/machine-operator.h"
12
13namespace v8 {
14namespace internal {
15namespace compiler {
16
17// Forward declarations.
18class CommonOperatorBuilder;
19class MachineGraph;
20class Word32Adapter;
21class Word64Adapter;
22
23// Performs constant folding and strength reduction on nodes that have
24// machine operators.
25class V8_EXPORT_PRIVATE MachineOperatorReducer final
26    : public NON_EXPORTED_BASE(AdvancedReducer) {
27 public:
28  explicit MachineOperatorReducer(Editor* editor, MachineGraph* mcgraph,
29                                  bool allow_signalling_nan = true);
30  ~MachineOperatorReducer() override;
31
32  const char* reducer_name() const override { return "MachineOperatorReducer"; }
33
34  Reduction Reduce(Node* node) override;
35
36 private:
37  friend class Word32Adapter;
38  friend class Word64Adapter;
39
40  Node* Float32Constant(volatile float value);
41  Node* Float64Constant(volatile double value);
42  Node* Int32Constant(int32_t value);
43  Node* Int64Constant(int64_t value);
44  Node* Uint32Constant(uint32_t value) {
45    return Int32Constant(bit_cast<int32_t>(value));
46  }
47  Node* Uint64Constant(uint64_t value) {
48    return Int64Constant(bit_cast<int64_t>(value));
49  }
50  Node* Float64Mul(Node* lhs, Node* rhs);
51  Node* Float64PowHalf(Node* value);
52  Node* Word32And(Node* lhs, Node* rhs);
53  Node* Word32And(Node* lhs, uint32_t rhs) {
54    return Word32And(lhs, Uint32Constant(rhs));
55  }
56  Node* Word32Sar(Node* lhs, uint32_t rhs);
57  Node* Word32Shr(Node* lhs, uint32_t rhs);
58  Node* Word32Equal(Node* lhs, Node* rhs);
59  Node* Word64And(Node* lhs, Node* rhs);
60  Node* Int32Add(Node* lhs, Node* rhs);
61  Node* Int32Sub(Node* lhs, Node* rhs);
62  Node* Int32Mul(Node* lhs, Node* rhs);
63  Node* Int32Div(Node* dividend, int32_t divisor);
64  Node* Uint32Div(Node* dividend, uint32_t divisor);
65  Node* TruncateInt64ToInt32(Node* value);
66
67  Reduction ReplaceBool(bool value) { return ReplaceInt32(value ? 1 : 0); }
68  Reduction ReplaceFloat32(volatile float value) {
69    return Replace(Float32Constant(value));
70  }
71  Reduction ReplaceFloat64(volatile double value) {
72    return Replace(Float64Constant(value));
73  }
74  Reduction ReplaceInt32(int32_t value) {
75    return Replace(Int32Constant(value));
76  }
77  Reduction ReplaceUint32(uint32_t value) {
78    return Replace(Uint32Constant(value));
79  }
80  Reduction ReplaceInt64(int64_t value) {
81    return Replace(Int64Constant(value));
82  }
83
84  Reduction ReduceInt32Add(Node* node);
85  Reduction ReduceInt64Add(Node* node);
86  Reduction ReduceInt32Sub(Node* node);
87  Reduction ReduceInt64Sub(Node* node);
88  Reduction ReduceInt64Mul(Node* node);
89  Reduction ReduceInt32Div(Node* node);
90  Reduction ReduceUint32Div(Node* node);
91  Reduction ReduceInt32Mod(Node* node);
92  Reduction ReduceUint32Mod(Node* node);
93  Reduction ReduceStore(Node* node);
94  Reduction ReduceProjection(size_t index, Node* node);
95  const Operator* Map64To32Comparison(const Operator* op, bool sign_extended);
96  Reduction ReduceWord32Comparisons(Node* node);
97  Reduction ReduceWord64Comparisons(Node* node);
98  Reduction ReduceWord32Shifts(Node* node);
99  Reduction ReduceWord32Shl(Node* node);
100  Reduction ReduceWord64Shl(Node* node);
101  Reduction ReduceWord32Shr(Node* node);
102  Reduction ReduceWord64Shr(Node* node);
103  Reduction ReduceWord32Sar(Node* node);
104  Reduction ReduceWord64Sar(Node* node);
105  Reduction ReduceWord32And(Node* node);
106  Reduction ReduceWord64And(Node* node);
107  Reduction TryMatchWord32Ror(Node* node);
108  Reduction ReduceWord32Or(Node* node);
109  Reduction ReduceWord64Or(Node* node);
110  Reduction ReduceWord32Xor(Node* node);
111  Reduction ReduceWord64Xor(Node* node);
112  Reduction ReduceWord32Equal(Node* node);
113  Reduction ReduceFloat64InsertLowWord32(Node* node);
114  Reduction ReduceFloat64InsertHighWord32(Node* node);
115  Reduction ReduceFloat64Compare(Node* node);
116  Reduction ReduceFloat64RoundDown(Node* node);
117  Reduction ReduceTruncateInt64ToInt32(Node* node);
118  Reduction ReduceConditional(Node* node);
119
120  Graph* graph() const;
121  MachineGraph* mcgraph() const { return mcgraph_; }
122  CommonOperatorBuilder* common() const;
123  MachineOperatorBuilder* machine() const;
124
125  // These reductions can be applied to operations of different word sizes.
126  // Use Word32Adapter or Word64Adapter to specialize for a particular one.
127  template <typename WordNAdapter>
128  Reduction ReduceWordNAnd(Node* node);
129  template <typename WordNAdapter>
130  Reduction ReduceWordNOr(Node* node);
131  template <typename WordNAdapter>
132  Reduction ReduceWordNXor(Node* node);
133
134  // Tries to simplify "if(x == 0)" by removing the "== 0" and inverting
135  // branches.
136  Reduction SimplifyBranch(Node* node);
137  // Helper for SimplifyBranch; swaps the if/else of a branch.
138  void SwapBranches(Node* node);
139
140  // Helper for ReduceConditional. Does not perform the actual reduction; just
141  // returns a new Node that could be used as the input to the condition.
142  template <typename WordNAdapter>
143  base::Optional<Node*> ReduceConditionalN(Node* node);
144
145  // Helper for finding a reduced equality condition. Does not perform the
146  // actual reduction; just returns a new pair that could be compared for the
147  // same outcome.
148  template <typename WordNAdapter>
149  base::Optional<std::pair<Node*, uint32_t>> ReduceWord32EqualForConstantRhs(
150      Node* lhs, uint32_t rhs);
151
152  MachineGraph* mcgraph_;
153  bool allow_signalling_nan_;
154};
155
156}  // namespace compiler
157}  // namespace internal
158}  // namespace v8
159
160#endif  // V8_COMPILER_MACHINE_OPERATOR_REDUCER_H_
161