Moved zones and zone related stuff in its own directory.

src/zone/zone.cc

 // Copyright 2012 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/zone.h"
+#include "src/zone/zone.h"
 
 #include <cstring>
 
 #include "src/v8.h"
 
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
 
 namespace v8 {
@@ skipping 18 matching lines @@
     USE(start);                                  \
     USE(size);                                   \
   } while (false)
 
 const size_t kASanRedzoneBytes = 0;
 
 #endif  // V8_USE_ADDRESS_SANITIZER
 
 }  // namespace
 
-
-// Segments represent chunks of memory: They have starting address
-// (encoded in the this pointer) and a size in bytes. Segments are
-// chained together forming a LIFO structure with the newest segment
-// available as segment_head_. Segments are allocated using malloc()
-// and de-allocated using free().
-
-class Segment {
- public:
-  void Initialize(Segment* next, size_t size) {
-    next_ = next;
-    size_ = size;
-  }
-
-  Segment* next() const { return next_; }
-  void clear_next() { next_ = nullptr; }
-
-  size_t size() const { return size_; }
-  size_t capacity() const { return size_ - sizeof(Segment); }
-
-  Address start() const { return address(sizeof(Segment)); }
-  Address end() const { return address(size_); }
-
- private:
-  // Computes the address of the nth byte in this segment.
-  Address address(size_t n) const { return Address(this) + n; }
-
-  Segment* next_;
-  size_t size_;
-};
-
-Zone::Zone(base::AccountingAllocator* allocator)
+Zone::Zone(AccountingAllocator* allocator)
     : allocation_size_(0),
       segment_bytes_allocated_(0),
       position_(0),
       limit_(0),
       allocator_(allocator),
       segment_head_(nullptr) {}
 
 Zone::~Zone() {
   DeleteAll();
   DeleteKeptSegment();
 
   DCHECK(segment_bytes_allocated_ == 0);
 }
 
-
 void* Zone::New(size_t size) {
   // Round up the requested size to fit the alignment.
   size = RoundUp(size, kAlignment);
 
   // If the allocation size is divisible by 8 then we return an 8-byte aligned
   // address.
   if (kPointerSize == 4 && kAlignment == 4) {
     position_ += ((~size) & 4) & (reinterpret_cast<intptr_t>(position_) & 4);
   } else {
     DCHECK(kAlignment >= kPointerSize);
@@ skipping 15 matching lines @@
   Address redzone_position = result + size;
   DCHECK(redzone_position + kASanRedzoneBytes == position_);
   ASAN_POISON_MEMORY_REGION(redzone_position, kASanRedzoneBytes);
 
   // Check that the result has the proper alignment and return it.
   DCHECK(IsAddressAligned(result, kAlignment, 0));
   allocation_size_ += size;
   return reinterpret_cast<void*>(result);
 }
 
-
 void Zone::DeleteAll() {
 #ifdef DEBUG
   // Constant byte value used for zapping dead memory in debug mode.
   static const unsigned char kZapDeadByte = 0xcd;
 #endif
 
   // Find a segment with a suitable size to keep around.
   Segment* keep = nullptr;
   // Traverse the chained list of segments, zapping (in debug mode)
   // and freeing every segment except the one we wish to keep.
   for (Segment* current = segment_head_; current;) {
     Segment* next = current->next();
     if (!keep && current->size() <= kMaximumKeptSegmentSize) {
       // Unlink the segment we wish to keep from the list.
       keep = current;
-      keep->clear_next();
+      keep->set_next(nullptr);
     } else {
       size_t size = current->size();
 #ifdef DEBUG
       // Un-poison first so the zapping doesn't trigger ASan complaints.
       ASAN_UNPOISON_MEMORY_REGION(current, size);
       // Zap the entire current segment (including the header).
       memset(current, kZapDeadByte, size);
 #endif
-      DeleteSegment(current, size);
+      segment_bytes_allocated_ -= size;
+      allocator_->FreeSegment(current);
     }
     current = next;
   }
 
   // If we have found a segment we want to keep, we must recompute the
   // variables 'position' and 'limit' to prepare for future allocate
   // attempts. Otherwise, we must clear the position and limit to
   // force a new segment to be allocated on demand.
   if (keep) {
     Address start = keep->start();
     position_ = RoundUp(start, kAlignment);
     limit_ = keep->end();
     // Un-poison so we can re-use the segment later.
     ASAN_UNPOISON_MEMORY_REGION(start, keep->capacity());
 #ifdef DEBUG
     // Zap the contents of the kept segment (but not the header).
     memset(start, kZapDeadByte, keep->capacity());
 #endif
   } else {
     position_ = limit_ = 0;
   }
 
   allocation_size_ = 0;
   // Update the head segment to be the kept segment (if any).
   segment_head_ = keep;
 }
 
-
 void Zone::DeleteKeptSegment() {
 #ifdef DEBUG
   // Constant byte value used for zapping dead memory in debug mode.
   static const unsigned char kZapDeadByte = 0xcd;
 #endif
 
   DCHECK(segment_head_ == nullptr || segment_head_->next() == nullptr);
   if (segment_head_ != nullptr) {
     size_t size = segment_head_->size();
 #ifdef DEBUG
     // Un-poison first so the zapping doesn't trigger ASan complaints.
     ASAN_UNPOISON_MEMORY_REGION(segment_head_, size);
     // Zap the entire kept segment (including the header).
     memset(segment_head_, kZapDeadByte, size);
 #endif
-    DeleteSegment(segment_head_, size);
+    segment_bytes_allocated_ -= size;
+    allocator_->FreeSegment(segment_head_);
     segment_head_ = nullptr;
   }
 
   DCHECK(segment_bytes_allocated_ == 0);
 }
 
-
 // Creates a new segment, sets it size, and pushes it to the front
 // of the segment chain. Returns the new segment.
 Segment* Zone::NewSegment(size_t size) {
-  Segment* result = reinterpret_cast<Segment*>(allocator_->Allocate(size));
+  Segment* result = allocator_->AllocateSegment(size);
   segment_bytes_allocated_ += size;
   if (result != nullptr) {
-    result->Initialize(segment_head_, size);
+    result->Initialize(segment_head_, size, this);
     segment_head_ = result;
   }
   return result;
 }
 
-
-// Deletes the given segment. Does not touch the segment chain.
-void Zone::DeleteSegment(Segment* segment, size_t size) {
-  segment_bytes_allocated_ -= size;
-  allocator_->Free(segment, size);
-}
-
-
 Address Zone::NewExpand(size_t size) {
   // Make sure the requested size is already properly aligned and that
   // there isn't enough room in the Zone to satisfy the request.
   DCHECK_EQ(size, RoundDown(size, kAlignment));
   DCHECK(limit_ < position_ ||
          reinterpret_cast<uintptr_t>(limit_) -
                  reinterpret_cast<uintptr_t>(position_) <
              size);
 
   // Compute the new segment size. We use a 'high water mark'
@@ skipping 38 matching lines @@
   // size bytes + header and alignment padding)
   DCHECK(reinterpret_cast<uintptr_t>(position_) >=
          reinterpret_cast<uintptr_t>(result));
   limit_ = segment->end();
   DCHECK(position_ <= limit_);
   return result;
 }
 
 }  // namespace internal
 }  // namespace v8