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28 #include "hydrogen-sce.h"
34 void HStackCheckEliminationPhase::Run() {
35 // For each loop block walk the dominator tree from the backwards branch to
36 // the loop header. If a call instruction is encountered the backwards branch
37 // is dominated by a call and the stack check in the backwards branch can be
39 for (int i = 0; i < graph()->blocks()->length(); i++) {
40 HBasicBlock* block = graph()->blocks()->at(i);
41 if (block->IsLoopHeader()) {
42 HBasicBlock* back_edge = block->loop_information()->GetLastBackEdge();
43 HBasicBlock* dominator = back_edge;
45 for (HInstructionIterator it(dominator); !it.Done(); it.Advance()) {
46 if (it.Current()->HasStackCheck()) {
47 block->loop_information()->stack_check()->Eliminate();
52 // Done when the loop header is processed.
53 if (dominator == block) break;
55 // Move up the dominator tree.
56 dominator = dominator->dominator();
62 } } // namespace v8::internal