| Index: src/hydrogen-environment-liveness.cc
|
| diff --git a/src/hydrogen-environment-liveness.cc b/src/hydrogen-environment-liveness.cc
|
| deleted file mode 100644
|
| index 7cc4dc04a849a13adbef61ab0c731aecc05cc923..0000000000000000000000000000000000000000
|
| --- a/src/hydrogen-environment-liveness.cc
|
| +++ /dev/null
|
| @@ -1,232 +0,0 @@
|
| -// Copyright 2013 the V8 project authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -
|
| -#include "src/hydrogen-environment-liveness.h"
|
| -
|
| -
|
| -namespace v8 {
|
| -namespace internal {
|
| -
|
| -
|
| -HEnvironmentLivenessAnalysisPhase::HEnvironmentLivenessAnalysisPhase(
|
| - HGraph* graph)
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| - : HPhase("H_Environment liveness analysis", graph),
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| - block_count_(graph->blocks()->length()),
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| - maximum_environment_size_(graph->maximum_environment_size()),
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| - live_at_block_start_(block_count_, zone()),
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| - first_simulate_(block_count_, zone()),
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| - first_simulate_invalid_for_index_(block_count_, zone()),
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| - markers_(maximum_environment_size_, zone()),
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| - collect_markers_(true),
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| - last_simulate_(NULL),
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| - went_live_since_last_simulate_(maximum_environment_size_, zone()) {
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| - DCHECK(maximum_environment_size_ > 0);
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| - for (int i = 0; i < block_count_; ++i) {
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| - live_at_block_start_.Add(
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| - new(zone()) BitVector(maximum_environment_size_, zone()), zone());
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| - first_simulate_.Add(NULL, zone());
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| - first_simulate_invalid_for_index_.Add(
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| - new(zone()) BitVector(maximum_environment_size_, zone()), zone());
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| - }
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| -}
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| -
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| -
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| -void HEnvironmentLivenessAnalysisPhase::ZapEnvironmentSlot(
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| - int index, HSimulate* simulate) {
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| - int operand_index = simulate->ToOperandIndex(index);
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| - if (operand_index == -1) {
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| - simulate->AddAssignedValue(index, graph()->GetConstantUndefined());
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| - } else {
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| - simulate->SetOperandAt(operand_index, graph()->GetConstantUndefined());
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| - }
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| -}
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| -
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| -
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| -void HEnvironmentLivenessAnalysisPhase::ZapEnvironmentSlotsInSuccessors(
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| - HBasicBlock* block, BitVector* live) {
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| - // When a value is live in successor A but dead in B, we must
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| - // explicitly zap it in B.
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| - for (HSuccessorIterator it(block->end()); !it.Done(); it.Advance()) {
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| - HBasicBlock* successor = it.Current();
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| - int successor_id = successor->block_id();
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| - BitVector* live_in_successor = live_at_block_start_[successor_id];
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| - if (live_in_successor->Equals(*live)) continue;
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| - for (int i = 0; i < live->length(); ++i) {
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| - if (!live->Contains(i)) continue;
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| - if (live_in_successor->Contains(i)) continue;
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| - if (first_simulate_invalid_for_index_.at(successor_id)->Contains(i)) {
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| - continue;
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| - }
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| - HSimulate* simulate = first_simulate_.at(successor_id);
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| - if (simulate == NULL) continue;
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| - DCHECK(VerifyClosures(simulate->closure(),
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| - block->last_environment()->closure()));
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| - ZapEnvironmentSlot(i, simulate);
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| - }
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| - }
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| -}
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| -
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| -
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| -void HEnvironmentLivenessAnalysisPhase::ZapEnvironmentSlotsForInstruction(
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| - HEnvironmentMarker* marker) {
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| - if (!marker->CheckFlag(HValue::kEndsLiveRange)) return;
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| - HSimulate* simulate = marker->next_simulate();
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| - if (simulate != NULL) {
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| - DCHECK(VerifyClosures(simulate->closure(), marker->closure()));
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| - ZapEnvironmentSlot(marker->index(), simulate);
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| - }
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| -}
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| -
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| -
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| -void HEnvironmentLivenessAnalysisPhase::UpdateLivenessAtBlockEnd(
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| - HBasicBlock* block,
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| - BitVector* live) {
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| - // Liveness at the end of each block: union of liveness in successors.
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| - live->Clear();
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| - for (HSuccessorIterator it(block->end()); !it.Done(); it.Advance()) {
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| - live->Union(*live_at_block_start_[it.Current()->block_id()]);
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| - }
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| -}
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| -
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| -
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| -void HEnvironmentLivenessAnalysisPhase::UpdateLivenessAtInstruction(
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| - HInstruction* instr,
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| - BitVector* live) {
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| - switch (instr->opcode()) {
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| - case HValue::kEnvironmentMarker: {
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| - HEnvironmentMarker* marker = HEnvironmentMarker::cast(instr);
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| - int index = marker->index();
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| - if (!live->Contains(index)) {
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| - marker->SetFlag(HValue::kEndsLiveRange);
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| - } else {
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| - marker->ClearFlag(HValue::kEndsLiveRange);
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| - }
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| - if (!went_live_since_last_simulate_.Contains(index)) {
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| - marker->set_next_simulate(last_simulate_);
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| - }
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| - if (marker->kind() == HEnvironmentMarker::LOOKUP) {
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| - live->Add(index);
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| - } else {
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| - DCHECK(marker->kind() == HEnvironmentMarker::BIND);
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| - live->Remove(index);
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| - went_live_since_last_simulate_.Add(index);
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| - }
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| - if (collect_markers_) {
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| - // Populate |markers_| list during the first pass.
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| - markers_.Add(marker, zone());
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| - }
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| - break;
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| - }
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| - case HValue::kLeaveInlined:
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| - // No environment values are live at the end of an inlined section.
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| - live->Clear();
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| - last_simulate_ = NULL;
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| -
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| - // The following DCHECKs guard the assumption used in case
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| - // kEnterInlined below:
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| - DCHECK(instr->next()->IsSimulate());
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| - DCHECK(instr->next()->next()->IsGoto());
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| -
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| - break;
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| - case HValue::kEnterInlined: {
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| - // Those environment values are live that are live at any return
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| - // target block. Here we make use of the fact that the end of an
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| - // inline sequence always looks like this: HLeaveInlined, HSimulate,
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| - // HGoto (to return_target block), with no environment lookups in
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| - // between (see DCHECKs above).
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| - HEnterInlined* enter = HEnterInlined::cast(instr);
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| - live->Clear();
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| - for (int i = 0; i < enter->return_targets()->length(); ++i) {
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| - int return_id = enter->return_targets()->at(i)->block_id();
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| - live->Union(*live_at_block_start_[return_id]);
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| - }
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| - last_simulate_ = NULL;
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| - break;
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| - }
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| - case HValue::kSimulate:
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| - last_simulate_ = HSimulate::cast(instr);
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| - went_live_since_last_simulate_.Clear();
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| - break;
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| - default:
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| - break;
|
| - }
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| -}
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| -
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| -
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| -void HEnvironmentLivenessAnalysisPhase::Run() {
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| - DCHECK(maximum_environment_size_ > 0);
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| -
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| - // Main iteration. Compute liveness of environment slots, and store it
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| - // for each block until it doesn't change any more. For efficiency, visit
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| - // blocks in reverse order and walk backwards through each block. We
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| - // need several iterations to propagate liveness through nested loops.
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| - BitVector live(maximum_environment_size_, zone());
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| - BitVector worklist(block_count_, zone());
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| - for (int i = 0; i < block_count_; ++i) {
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| - worklist.Add(i);
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| - }
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| - while (!worklist.IsEmpty()) {
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| - for (int block_id = block_count_ - 1; block_id >= 0; --block_id) {
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| - if (!worklist.Contains(block_id)) {
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| - continue;
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| - }
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| - worklist.Remove(block_id);
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| - last_simulate_ = NULL;
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| -
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| - HBasicBlock* block = graph()->blocks()->at(block_id);
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| - UpdateLivenessAtBlockEnd(block, &live);
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| -
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| - for (HInstruction* instr = block->end(); instr != NULL;
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| - instr = instr->previous()) {
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| - UpdateLivenessAtInstruction(instr, &live);
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| - }
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| -
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| - // Reached the start of the block, do necessary bookkeeping:
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| - // store computed information for this block and add predecessors
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| - // to the work list as necessary.
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| - first_simulate_.Set(block_id, last_simulate_);
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| - first_simulate_invalid_for_index_[block_id]->CopyFrom(
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| - went_live_since_last_simulate_);
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| - if (live_at_block_start_[block_id]->UnionIsChanged(live)) {
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| - for (int i = 0; i < block->predecessors()->length(); ++i) {
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| - worklist.Add(block->predecessors()->at(i)->block_id());
|
| - }
|
| - if (block->IsInlineReturnTarget()) {
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| - worklist.Add(block->inlined_entry_block()->block_id());
|
| - }
|
| - }
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| - }
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| - // Only collect bind/lookup instructions during the first pass.
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| - collect_markers_ = false;
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| - }
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| -
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| - // Analysis finished. Zap dead environment slots.
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| - for (int i = 0; i < markers_.length(); ++i) {
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| - ZapEnvironmentSlotsForInstruction(markers_[i]);
|
| - }
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| - for (int block_id = block_count_ - 1; block_id >= 0; --block_id) {
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| - HBasicBlock* block = graph()->blocks()->at(block_id);
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| - UpdateLivenessAtBlockEnd(block, &live);
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| - ZapEnvironmentSlotsInSuccessors(block, &live);
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| - }
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| -
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| - // Finally, remove the HEnvironment{Bind,Lookup} markers.
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| - for (int i = 0; i < markers_.length(); ++i) {
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| - markers_[i]->DeleteAndReplaceWith(NULL);
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| - }
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| -}
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| -
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| -
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| -#ifdef DEBUG
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| -bool HEnvironmentLivenessAnalysisPhase::VerifyClosures(
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| - Handle<JSFunction> a, Handle<JSFunction> b) {
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| - Heap::RelocationLock for_heap_access(isolate()->heap());
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| - AllowHandleDereference for_verification;
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| - return a.is_identical_to(b);
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| -}
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| -#endif
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| -
|
| -} // namespace internal
|
| -} // namespace v8
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|
|