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27
28#include "hydrogen-infer-types.h"
29
30namespace v8 {
31namespace internal {
32
33void HInferTypesPhase::InferTypes(int from_inclusive, int to_inclusive) {
34  for (int i = from_inclusive; i <= to_inclusive; ++i) {
35    HBasicBlock* block = graph()->blocks()->at(i);
36
37    const ZoneList<HPhi*>* phis = block->phis();
38    for (int j = 0; j < phis->length(); j++) {
39      phis->at(j)->UpdateInferredType();
40    }
41
42    for (HInstructionIterator it(block); !it.Done(); it.Advance()) {
43      it.Current()->UpdateInferredType();
44    }
45
46    if (block->IsLoopHeader()) {
47      HBasicBlock* last_back_edge =
48          block->loop_information()->GetLastBackEdge();
49      InferTypes(i + 1, last_back_edge->block_id());
50      // Skip all blocks already processed by the recursive call.
51      i = last_back_edge->block_id();
52      // Update phis of the loop header now after the whole loop body is
53      // guaranteed to be processed.
54      for (int j = 0; j < block->phis()->length(); ++j) {
55        HPhi* phi = block->phis()->at(j);
56        worklist_.Add(phi, zone());
57        in_worklist_.Add(phi->id());
58      }
59      while (!worklist_.is_empty()) {
60        HValue* current = worklist_.RemoveLast();
61        in_worklist_.Remove(current->id());
62        if (current->UpdateInferredType()) {
63          for (HUseIterator it(current->uses()); !it.Done(); it.Advance()) {
64            HValue* use = it.value();
65            if (!in_worklist_.Contains(use->id())) {
66              in_worklist_.Add(use->id());
67              worklist_.Add(use, zone());
68            }
69          }
70        }
71      }
72      ASSERT(in_worklist_.IsEmpty());
73    }
74  }
75}
76
77} }  // namespace v8::internal
78