Use MemoryChunk-based allocation for deoptimization entry code

src/spaces.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 635 matching lines @@
     return static_cast<int>(area_end() - area_start());
   }
 
   // Approximate amount of physical memory committed for this chunk.
   size_t CommittedPhysicalMemory() {
     return high_water_mark_;
   }
 
   static inline void UpdateHighWaterMark(Address mark);
 
+  // Commit chunk body up to the body_size. If body_size is within the
+  // committed size, the committed pages are never uncommitted.

[danno, 2013/01/17 16:00:55]

Why not uncommit? It seems to me that uncommitting would be more consistent.

[haitao.feng, 2013/01/18 12:59:26]

Done.

+  bool CommitBody(size_t body_size, Executability executable);
+
  protected:
   MemoryChunk* next_chunk_;
   MemoryChunk* prev_chunk_;
   size_t size_;
   intptr_t flags_;
 
   // Start and end of allocatable memory on this chunk.
   Address area_start_;
   Address area_end_;
 
@@ skipping 214 matching lines @@
   bool exists() { return this != NULL && code_range_ != NULL; }
   bool contains(Address address) {
     if (this == NULL || code_range_ == NULL) return false;
     Address start = static_cast<Address>(code_range_->address());
     return start <= address && address < start + code_range_->size();
   }
 
   // Allocates a chunk of memory from the large-object portion of
   // the code range.  On platforms with no separate code range, should
   // not be called.
-  MUST_USE_RESULT Address AllocateRawMemory(const size_t requested,
+  MUST_USE_RESULT Address AllocateRawMemory(const size_t requested_size,
+                                            const size_t commit_size,
                                             size_t* allocated);
+  bool CommitRawMemory(Address start, size_t length);
   void FreeRawMemory(Address buf, size_t length);
 
  private:
   Isolate* isolate_;
 
   // The reserved range of virtual memory that all code objects are put in.
   VirtualMemory* code_range_;
   // Plain old data class, just a struct plus a constructor.
   class FreeBlock {
    public:
@@ skipping 127 matching lines @@
   // Returns maximum available bytes that the old space can have.
   intptr_t MaxAvailable() {
     return (Available() / Page::kPageSize) * Page::kMaxNonCodeHeapObjectSize;
   }
 
 #ifdef DEBUG
   // Reports statistic info of the space.
   void ReportStatistics();
 #endif
 
-  MemoryChunk* AllocateChunk(intptr_t body_size,
+  // After calling this function, the memory region from commit_body_size to

[danno, 2013/01/17 16:00:55]

How about just:
// Returns a MemoryChunk in which the memory region from ... 

[haitao.feng, 2013/01/18 12:59:26]

Done.

+  // reserve_body_size of the body is reserved but not committed, they could be

[danno, 2013/01/17 16:00:55]

nit: s/they could/it could/

[haitao.feng, 2013/01/18 12:59:26]

Done.

+  // committed later by calling MemoryChunk::CommitBody with a new body size.
+  MemoryChunk* AllocateChunk(intptr_t reserve_body_size,
+                             intptr_t commit_body_size,
                              Executability executable,
                              Space* space);
 
   Address ReserveAlignedMemory(size_t requested,
                                size_t alignment,
                                VirtualMemory* controller);
-  Address AllocateAlignedMemory(size_t requested,
+  Address AllocateAlignedMemory(size_t requested_size,

[danno, 2013/01/17 16:00:55]

 s/requested_size/reserve_size/

[haitao.feng, 2013/01/18 12:59:26]

Done.

+                                size_t commit_size,
                                 size_t alignment,
                                 Executability executable,
                                 VirtualMemory* controller);
 
   void FreeMemory(VirtualMemory* reservation, Executability executable);
   void FreeMemory(Address addr, size_t size, Executability executable);
 
   // Commit a contiguous block of memory from the initial chunk.  Assumes that
   // the address is not NULL, the size is greater than zero, and that the
   // block is contained in the initial chunk.  Returns true if it succeeded
@@ skipping 29 matching lines @@
   static int CodePageGuardSize();
 
   static int CodePageAreaStartOffset();
 
   static int CodePageAreaEndOffset();
 
   static int CodePageAreaSize() {
     return CodePageAreaEndOffset() - CodePageAreaStartOffset();
   }
 
-  MUST_USE_RESULT static bool CommitCodePage(VirtualMemory* vm,
-                                             Address start,
-                                             size_t size);
+  MUST_USE_RESULT static bool CommitExecutableMemory(VirtualMemory* vm,
+                                                     Address start,
+                                                     size_t commit_size,
+                                                     size_t reserved_size);
 
  private:
   Isolate* isolate_;
 
   // Maximum space size in bytes.
   size_t capacity_;
   // Maximum subset of capacity_ that can be executable
   size_t capacity_executable_;
 
   // Allocated space size in bytes.
@@ skipping 1654 matching lines @@
   }
   // Must be small, since an iteration is used for lookup.
   static const int kMaxComments = 64;
 };
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_