1 // Copyright 2015 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/js-frame-specialization.h"
6
7 #include "src/compiler/js-graph.h"
8 #include "src/compiler/linkage.h"
9 #include "src/frames-inl.h"
10
11 namespace v8 {
12 namespace internal {
13 namespace compiler {
14
Reduce(Node * node)15 Reduction JSFrameSpecialization::Reduce(Node* node) {
16 switch (node->opcode()) {
17 case IrOpcode::kOsrValue:
18 return ReduceOsrValue(node);
19 case IrOpcode::kOsrGuard:
20 return ReduceOsrGuard(node);
21 case IrOpcode::kParameter:
22 return ReduceParameter(node);
23 default:
24 break;
25 }
26 return NoChange();
27 }
28
ReduceOsrValue(Node * node)29 Reduction JSFrameSpecialization::ReduceOsrValue(Node* node) {
30 DCHECK_EQ(IrOpcode::kOsrValue, node->opcode());
31 Handle<Object> value;
32 int index = OsrValueIndexOf(node->op());
33 int const parameters_count = frame()->ComputeParametersCount() + 1;
34 if (index == Linkage::kOsrContextSpillSlotIndex) {
35 value = handle(frame()->context(), isolate());
36 } else if (index >= parameters_count) {
37 value = handle(frame()->GetExpression(index - parameters_count), isolate());
38 } else {
39 // The OsrValue index 0 is the receiver.
40 value =
41 handle(index ? frame()->GetParameter(index - 1) : frame()->receiver(),
42 isolate());
43 }
44 return Replace(jsgraph()->Constant(value));
45 }
46
ReduceOsrGuard(Node * node)47 Reduction JSFrameSpecialization::ReduceOsrGuard(Node* node) {
48 DCHECK_EQ(IrOpcode::kOsrGuard, node->opcode());
49 ReplaceWithValue(node, node->InputAt(0),
50 NodeProperties::GetEffectInput(node));
51 return Changed(node);
52 }
53
ReduceParameter(Node * node)54 Reduction JSFrameSpecialization::ReduceParameter(Node* node) {
55 DCHECK_EQ(IrOpcode::kParameter, node->opcode());
56 Handle<Object> value;
57 int const index = ParameterIndexOf(node->op());
58 int const parameters_count = frame()->ComputeParametersCount() + 1;
59 if (index == Linkage::kJSCallClosureParamIndex) {
60 // The Parameter index references the closure.
61 value = handle(frame()->function(), isolate());
62 } else if (index == Linkage::GetJSCallArgCountParamIndex(parameters_count)) {
63 // The Parameter index references the parameter count.
64 value = handle(Smi::FromInt(parameters_count - 1), isolate());
65 } else if (index == Linkage::GetJSCallContextParamIndex(parameters_count)) {
66 // The Parameter index references the context.
67 value = handle(frame()->context(), isolate());
68 } else {
69 // The Parameter index 0 is the receiver.
70 value =
71 handle(index ? frame()->GetParameter(index - 1) : frame()->receiver(),
72 isolate());
73 }
74 return Replace(jsgraph()->Constant(value));
75 }
76
77
isolate() const78 Isolate* JSFrameSpecialization::isolate() const { return jsgraph()->isolate(); }
79
80 } // namespace compiler
81 } // namespace internal
82 } // namespace v8
83