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#include "src/compiler/simplified-operator-reducer.h"
6
7#include "src/compiler/js-graph.h"
8#include "src/compiler/machine-operator.h"
9#include "src/compiler/node-matchers.h"
10#include "src/compiler/operator-properties.h"
11#include "src/compiler/simplified-operator.h"
12#include "src/compiler/type-cache.h"
13#include "src/conversions-inl.h"
14
15namespace v8 {
16namespace internal {
17namespace compiler {
18
19namespace {
20
21Decision DecideObjectIsSmi(Node* const input) {
22  NumberMatcher m(input);
23  if (m.HasValue()) {
24    return IsSmiDouble(m.Value()) ? Decision::kTrue : Decision::kFalse;
25  }
26  if (m.IsAllocate()) return Decision::kFalse;
27  if (m.IsChangeBitToTagged()) return Decision::kFalse;
28  if (m.IsChangeInt31ToTaggedSigned()) return Decision::kTrue;
29  if (m.IsHeapConstant()) return Decision::kFalse;
30  return Decision::kUnknown;
31}
32
33}  // namespace
34
35SimplifiedOperatorReducer::SimplifiedOperatorReducer(Editor* editor,
36                                                     JSGraph* jsgraph)
37    : AdvancedReducer(editor), jsgraph_(jsgraph) {}
38
39SimplifiedOperatorReducer::~SimplifiedOperatorReducer() {}
40
41
42Reduction SimplifiedOperatorReducer::Reduce(Node* node) {
43  switch (node->opcode()) {
44    case IrOpcode::kBooleanNot: {
45      HeapObjectMatcher m(node->InputAt(0));
46      if (m.Is(factory()->true_value())) return ReplaceBoolean(false);
47      if (m.Is(factory()->false_value())) return ReplaceBoolean(true);
48      if (m.IsBooleanNot()) return Replace(m.InputAt(0));
49      break;
50    }
51    case IrOpcode::kChangeBitToTagged: {
52      Int32Matcher m(node->InputAt(0));
53      if (m.Is(0)) return Replace(jsgraph()->FalseConstant());
54      if (m.Is(1)) return Replace(jsgraph()->TrueConstant());
55      if (m.IsChangeTaggedToBit()) return Replace(m.InputAt(0));
56      break;
57    }
58    case IrOpcode::kChangeTaggedToBit: {
59      HeapObjectMatcher m(node->InputAt(0));
60      if (m.HasValue()) return ReplaceInt32(m.Value()->BooleanValue());
61      if (m.IsChangeBitToTagged()) return Replace(m.InputAt(0));
62      break;
63    }
64    case IrOpcode::kChangeFloat64ToTagged: {
65      Float64Matcher m(node->InputAt(0));
66      if (m.HasValue()) return ReplaceNumber(m.Value());
67      if (m.IsChangeTaggedToFloat64()) return Replace(m.node()->InputAt(0));
68      break;
69    }
70    case IrOpcode::kChangeInt31ToTaggedSigned:
71    case IrOpcode::kChangeInt32ToTagged: {
72      Int32Matcher m(node->InputAt(0));
73      if (m.HasValue()) return ReplaceNumber(m.Value());
74      if (m.IsChangeTaggedToInt32() || m.IsChangeTaggedSignedToInt32()) {
75        return Replace(m.InputAt(0));
76      }
77      break;
78    }
79    case IrOpcode::kChangeTaggedToFloat64:
80    case IrOpcode::kTruncateTaggedToFloat64: {
81      NumberMatcher m(node->InputAt(0));
82      if (m.HasValue()) return ReplaceFloat64(m.Value());
83      if (m.IsChangeFloat64ToTagged() || m.IsChangeFloat64ToTaggedPointer()) {
84        return Replace(m.node()->InputAt(0));
85      }
86      if (m.IsChangeInt31ToTaggedSigned() || m.IsChangeInt32ToTagged()) {
87        return Change(node, machine()->ChangeInt32ToFloat64(), m.InputAt(0));
88      }
89      if (m.IsChangeUint32ToTagged()) {
90        return Change(node, machine()->ChangeUint32ToFloat64(), m.InputAt(0));
91      }
92      break;
93    }
94    case IrOpcode::kChangeTaggedSignedToInt32:
95    case IrOpcode::kChangeTaggedToInt32: {
96      NumberMatcher m(node->InputAt(0));
97      if (m.HasValue()) return ReplaceInt32(DoubleToInt32(m.Value()));
98      if (m.IsChangeFloat64ToTagged() || m.IsChangeFloat64ToTaggedPointer()) {
99        return Change(node, machine()->ChangeFloat64ToInt32(), m.InputAt(0));
100      }
101      if (m.IsChangeInt31ToTaggedSigned() || m.IsChangeInt32ToTagged()) {
102        return Replace(m.InputAt(0));
103      }
104      break;
105    }
106    case IrOpcode::kChangeTaggedToUint32: {
107      NumberMatcher m(node->InputAt(0));
108      if (m.HasValue()) return ReplaceUint32(DoubleToUint32(m.Value()));
109      if (m.IsChangeFloat64ToTagged() || m.IsChangeFloat64ToTaggedPointer()) {
110        return Change(node, machine()->ChangeFloat64ToUint32(), m.InputAt(0));
111      }
112      if (m.IsChangeUint32ToTagged()) return Replace(m.InputAt(0));
113      break;
114    }
115    case IrOpcode::kChangeUint32ToTagged: {
116      Uint32Matcher m(node->InputAt(0));
117      if (m.HasValue()) return ReplaceNumber(FastUI2D(m.Value()));
118      break;
119    }
120    case IrOpcode::kTruncateTaggedToWord32: {
121      NumberMatcher m(node->InputAt(0));
122      if (m.HasValue()) return ReplaceInt32(DoubleToInt32(m.Value()));
123      if (m.IsChangeInt31ToTaggedSigned() || m.IsChangeInt32ToTagged() ||
124          m.IsChangeUint32ToTagged()) {
125        return Replace(m.InputAt(0));
126      }
127      if (m.IsChangeFloat64ToTagged() || m.IsChangeFloat64ToTaggedPointer()) {
128        return Change(node, machine()->TruncateFloat64ToWord32(), m.InputAt(0));
129      }
130      break;
131    }
132    case IrOpcode::kCheckedFloat64ToInt32: {
133      Float64Matcher m(node->InputAt(0));
134      if (m.HasValue() && IsInt32Double(m.Value())) {
135        Node* value = jsgraph()->Int32Constant(static_cast<int32_t>(m.Value()));
136        ReplaceWithValue(node, value);
137        return Replace(value);
138      }
139      break;
140    }
141    case IrOpcode::kCheckedTaggedToInt32:
142    case IrOpcode::kCheckedTaggedSignedToInt32: {
143      NodeMatcher m(node->InputAt(0));
144      if (m.IsConvertTaggedHoleToUndefined()) {
145        node->ReplaceInput(0, m.InputAt(0));
146        return Changed(node);
147      }
148      break;
149    }
150    case IrOpcode::kCheckIf: {
151      HeapObjectMatcher m(node->InputAt(0));
152      if (m.Is(factory()->true_value())) {
153        Node* const effect = NodeProperties::GetEffectInput(node);
154        return Replace(effect);
155      }
156      break;
157    }
158    case IrOpcode::kCheckNumber: {
159      NodeMatcher m(node->InputAt(0));
160      if (m.IsConvertTaggedHoleToUndefined()) {
161        node->ReplaceInput(0, m.InputAt(0));
162        return Changed(node);
163      }
164      break;
165    }
166    case IrOpcode::kCheckHeapObject: {
167      Node* const input = node->InputAt(0);
168      if (DecideObjectIsSmi(input) == Decision::kFalse) {
169        ReplaceWithValue(node, input);
170        return Replace(input);
171      }
172      NodeMatcher m(input);
173      if (m.IsCheckHeapObject()) {
174        ReplaceWithValue(node, input);
175        return Replace(input);
176      }
177      break;
178    }
179    case IrOpcode::kCheckSmi: {
180      Node* const input = node->InputAt(0);
181      if (DecideObjectIsSmi(input) == Decision::kTrue) {
182        ReplaceWithValue(node, input);
183        return Replace(input);
184      }
185      NodeMatcher m(input);
186      if (m.IsCheckSmi()) {
187        ReplaceWithValue(node, input);
188        return Replace(input);
189      } else if (m.IsConvertTaggedHoleToUndefined()) {
190        node->ReplaceInput(0, m.InputAt(0));
191        return Changed(node);
192      }
193      break;
194    }
195    case IrOpcode::kObjectIsSmi: {
196      Node* const input = node->InputAt(0);
197      switch (DecideObjectIsSmi(input)) {
198        case Decision::kTrue:
199          return ReplaceBoolean(true);
200        case Decision::kFalse:
201          return ReplaceBoolean(false);
202        case Decision::kUnknown:
203          break;
204      }
205      break;
206    }
207    case IrOpcode::kNumberAbs: {
208      NumberMatcher m(node->InputAt(0));
209      if (m.HasValue()) return ReplaceNumber(std::fabs(m.Value()));
210      break;
211    }
212    case IrOpcode::kReferenceEqual: {
213      HeapObjectBinopMatcher m(node);
214      if (m.left().node() == m.right().node()) return ReplaceBoolean(true);
215      break;
216    }
217    default:
218      break;
219  }
220  return NoChange();
221}
222
223Reduction SimplifiedOperatorReducer::Change(Node* node, const Operator* op,
224                                            Node* a) {
225  DCHECK_EQ(node->InputCount(), OperatorProperties::GetTotalInputCount(op));
226  DCHECK_LE(1, node->InputCount());
227  node->ReplaceInput(0, a);
228  NodeProperties::ChangeOp(node, op);
229  return Changed(node);
230}
231
232Reduction SimplifiedOperatorReducer::ReplaceBoolean(bool value) {
233  return Replace(jsgraph()->BooleanConstant(value));
234}
235
236Reduction SimplifiedOperatorReducer::ReplaceFloat64(double value) {
237  return Replace(jsgraph()->Float64Constant(value));
238}
239
240
241Reduction SimplifiedOperatorReducer::ReplaceInt32(int32_t value) {
242  return Replace(jsgraph()->Int32Constant(value));
243}
244
245
246Reduction SimplifiedOperatorReducer::ReplaceNumber(double value) {
247  return Replace(jsgraph()->Constant(value));
248}
249
250
251Reduction SimplifiedOperatorReducer::ReplaceNumber(int32_t value) {
252  return Replace(jsgraph()->Constant(value));
253}
254
255Factory* SimplifiedOperatorReducer::factory() const {
256  return isolate()->factory();
257}
258
259Graph* SimplifiedOperatorReducer::graph() const { return jsgraph()->graph(); }
260
261Isolate* SimplifiedOperatorReducer::isolate() const {
262  return jsgraph()->isolate();
263}
264
265MachineOperatorBuilder* SimplifiedOperatorReducer::machine() const {
266  return jsgraph()->machine();
267}
268
269}  // namespace compiler
270}  // namespace internal
271}  // namespace v8
272