Replaced different means of zone pooling/reusing by one zone segment pool

src/compiler/zone-pool.cc

Index: src/compiler/zone-pool.cc
diff --git a/src/compiler/zone-pool.cc b/src/compiler/zone-pool.cc
deleted file mode 100644
index 7681eeb5d17dbc831b96372cddf438cdd0d6906e..0000000000000000000000000000000000000000
--- a/src/compiler/zone-pool.cc
+++ /dev/null
@@ -1,138 +0,0 @@
-// Copyright 2014 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/compiler/zone-pool.h"
-
-namespace v8 {
-namespace internal {
-namespace compiler {
-
-ZonePool::StatsScope::StatsScope(ZonePool* zone_pool)
-    : zone_pool_(zone_pool),
-      total_allocated_bytes_at_start_(zone_pool->GetTotalAllocatedBytes()),
-      max_allocated_bytes_(0) {
-  zone_pool_->stats_.push_back(this);
-  for (Zone* zone : zone_pool_->used_) {
-    size_t size = static_cast<size_t>(zone->allocation_size());
-    std::pair<InitialValues::iterator, bool> res =
-        initial_values_.insert(std::make_pair(zone, size));
-    USE(res);
-    DCHECK(res.second);
-  }
-}
-
-
-ZonePool::StatsScope::~StatsScope() {
-  DCHECK_EQ(zone_pool_->stats_.back(), this);
-  zone_pool_->stats_.pop_back();
-}
-
-
-size_t ZonePool::StatsScope::GetMaxAllocatedBytes() {
-  return std::max(max_allocated_bytes_, GetCurrentAllocatedBytes());
-}
-
-
-size_t ZonePool::StatsScope::GetCurrentAllocatedBytes() {
-  size_t total = 0;
-  for (Zone* zone : zone_pool_->used_) {
-    total += static_cast<size_t>(zone->allocation_size());
-    // Adjust for initial values.
-    InitialValues::iterator it = initial_values_.find(zone);
-    if (it != initial_values_.end()) {
-      total -= it->second;
-    }
-  }
-  return total;
-}
-
-
-size_t ZonePool::StatsScope::GetTotalAllocatedBytes() {
-  return zone_pool_->GetTotalAllocatedBytes() - total_allocated_bytes_at_start_;
-}
-
-
-void ZonePool::StatsScope::ZoneReturned(Zone* zone) {
-  size_t current_total = GetCurrentAllocatedBytes();
-  // Update max.
-  max_allocated_bytes_ = std::max(max_allocated_bytes_, current_total);
-  // Drop zone from initial value map.
-  InitialValues::iterator it = initial_values_.find(zone);
-  if (it != initial_values_.end()) {
-    initial_values_.erase(it);
-  }
-}
-
-ZonePool::ZonePool(AccountingAllocator* allocator)
-    : max_allocated_bytes_(0), total_deleted_bytes_(0), allocator_(allocator) {}
-
-ZonePool::~ZonePool() {
-  DCHECK(used_.empty());
-  DCHECK(stats_.empty());
-  for (Zone* zone : unused_) {
-    delete zone;
-  }
-}
-
-
-size_t ZonePool::GetMaxAllocatedBytes() {
-  return std::max(max_allocated_bytes_, GetCurrentAllocatedBytes());
-}
-
-
-size_t ZonePool::GetCurrentAllocatedBytes() {
-  size_t total = 0;
-  for (Zone* zone : used_) {
-    total += static_cast<size_t>(zone->allocation_size());
-  }
-  return total;
-}
-
-
-size_t ZonePool::GetTotalAllocatedBytes() {
-  return total_deleted_bytes_ + GetCurrentAllocatedBytes();
-}
-
-
-Zone* ZonePool::NewEmptyZone() {
-  Zone* zone;
-  // Grab a zone from pool if possible.
-  if (!unused_.empty()) {
-    zone = unused_.back();
-    unused_.pop_back();
-  } else {
-    zone = new Zone(allocator_);
-  }
-  used_.push_back(zone);
-  DCHECK_EQ(0u, zone->allocation_size());
-  return zone;
-}
-
-
-void ZonePool::ReturnZone(Zone* zone) {
-  size_t current_total = GetCurrentAllocatedBytes();
-  // Update max.
-  max_allocated_bytes_ = std::max(max_allocated_bytes_, current_total);
-  // Update stats.
-  for (StatsScope* stat_scope : stats_) {
-    stat_scope->ZoneReturned(zone);
-  }
-  // Remove from used.
-  Used::iterator it = std::find(used_.begin(), used_.end(), zone);
-  DCHECK(it != used_.end());
-  used_.erase(it);
-  total_deleted_bytes_ += static_cast<size_t>(zone->allocation_size());
-  // Delete zone or clear and stash on unused_.
-  if (unused_.size() >= kMaxUnusedSize) {
-    delete zone;
-  } else {
-    zone->DeleteAll();
-    DCHECK_EQ(0u, zone->allocation_size());
-    unused_.push_back(zone);
-  }
-}
-
-}  // namespace compiler
-}  // namespace internal
-}  // namespace v8