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27
28 #include "hydrogen-mark-deoptimize.h"
29
30 namespace v8 {
31 namespace internal {
32
Run()33 void HMarkDeoptimizeOnUndefinedPhase::Run() {
34 const ZoneList<HPhi*>* phi_list = graph()->phi_list();
35 for (int i = 0; i < phi_list->length(); i++) {
36 HPhi* phi = phi_list->at(i);
37 if (phi->CheckFlag(HValue::kAllowUndefinedAsNaN) &&
38 !phi->CheckUsesForFlag(HValue::kAllowUndefinedAsNaN)) {
39 ProcessPhi(phi);
40 }
41 }
42 }
43
44
ProcessPhi(HPhi * phi)45 void HMarkDeoptimizeOnUndefinedPhase::ProcessPhi(HPhi* phi) {
46 ASSERT(phi->CheckFlag(HValue::kAllowUndefinedAsNaN));
47 ASSERT(worklist_.is_empty());
48
49 // Push the phi onto the worklist
50 phi->ClearFlag(HValue::kAllowUndefinedAsNaN);
51 worklist_.Add(phi, zone());
52
53 // Process all phis that can reach this phi
54 while (!worklist_.is_empty()) {
55 phi = worklist_.RemoveLast();
56 for (int i = phi->OperandCount() - 1; i >= 0; --i) {
57 HValue* input = phi->OperandAt(i);
58 if (input->IsPhi() && input->CheckFlag(HValue::kAllowUndefinedAsNaN)) {
59 input->ClearFlag(HValue::kAllowUndefinedAsNaN);
60 worklist_.Add(HPhi::cast(input), zone());
61 }
62 }
63 }
64 }
65
66
Run()67 void HComputeChangeUndefinedToNaN::Run() {
68 const ZoneList<HBasicBlock*>* blocks(graph()->blocks());
69 for (int i = 0; i < blocks->length(); ++i) {
70 const HBasicBlock* block(blocks->at(i));
71 for (HInstruction* current = block->first(); current != NULL; ) {
72 HInstruction* next = current->next();
73 if (current->IsChange()) {
74 if (HChange::cast(current)->can_convert_undefined_to_nan()) {
75 current->SetFlag(HValue::kAllowUndefinedAsNaN);
76 }
77 }
78 current = next;
79 }
80 }
81 }
82
83
84 } } // namespace v8::internal
85