Add v8_os_page_size flag for cross compilation

src/heap/spaces.cc

 // Copyright 2011 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/heap/spaces.h"
 
 #include <utility>
 
 #include "src/base/bits.h"
 #include "src/base/platform/platform.h"
@@ skipping 89 matching lines @@
     } else {
       return true;
     }
   }
 
   if (requested <= kMinimumCodeRangeSize) {
     requested = kMinimumCodeRangeSize;
   }
 
   const size_t reserved_area =
-      kReservedCodeRangePages * base::OS::CommitPageSize();
+      kReservedCodeRangePages * MemoryAllocator::GetCommitPageSize();
   if (requested < (kMaximalCodeRangeSize - reserved_area))
     requested += reserved_area;
 
   DCHECK(!kRequiresCodeRange || requested <= kMaximalCodeRangeSize);
 
   code_range_ = new base::VirtualMemory(
       requested, Max(kCodeRangeAreaAlignment,
                      static_cast<size_t>(base::OS::AllocateAlignment())));
   CHECK(code_range_ != NULL);
   if (!code_range_->IsReserved()) {
@@ skipping 420 matching lines @@
   return chunk;
 }
 
 
 // Commit MemoryChunk area to the requested size.
 bool MemoryChunk::CommitArea(size_t requested) {
   size_t guard_size =
       IsFlagSet(IS_EXECUTABLE) ? MemoryAllocator::CodePageGuardSize() : 0;
   size_t header_size = area_start() - address() - guard_size;
   size_t commit_size =
-      RoundUp(header_size + requested, base::OS::CommitPageSize());
+      RoundUp(header_size + requested, MemoryAllocator::GetCommitPageSize());
   size_t committed_size = RoundUp(header_size + (area_end() - area_start()),
-                                  base::OS::CommitPageSize());
+                                  MemoryAllocator::GetCommitPageSize());
 
   if (commit_size > committed_size) {
     // Commit size should be less or equal than the reserved size.
     DCHECK(commit_size <= size() - 2 * guard_size);
     // Append the committed area.
     Address start = address() + committed_size + guard_size;
     size_t length = commit_size - committed_size;
     if (reservation_.IsReserved()) {
       Executability executable =
           IsFlagSet(IS_EXECUTABLE) ? EXECUTABLE : NOT_EXECUTABLE;
@@ skipping 47 matching lines @@
 void MemoryChunk::Unlink() {
   MemoryChunk* next_element = next_chunk();
   MemoryChunk* prev_element = prev_chunk();
   next_element->set_prev_chunk(prev_element);
   prev_element->set_next_chunk(next_element);
   set_prev_chunk(NULL);
   set_next_chunk(NULL);
 }
 
 void MemoryAllocator::ShrinkChunk(MemoryChunk* chunk, size_t bytes_to_shrink) {
-  DCHECK_GE(bytes_to_shrink, static_cast<size_t>(base::OS::CommitPageSize()));
-  DCHECK_EQ(0u, bytes_to_shrink % base::OS::CommitPageSize());
+  DCHECK_GE(bytes_to_shrink, static_cast<size_t>(GetCommitPageSize()));
+  DCHECK_EQ(0u, bytes_to_shrink % GetCommitPageSize());
   Address free_start = chunk->area_end_ - bytes_to_shrink;
   // Don't adjust the size of the page. The area is just uncomitted but not
   // released.
   chunk->area_end_ -= bytes_to_shrink;
   UncommitBlock(free_start, bytes_to_shrink);
   if (chunk->IsFlagSet(MemoryChunk::IS_EXECUTABLE)) {
     if (chunk->reservation_.IsReserved())
       chunk->reservation_.Guard(chunk->area_end_);
     else
-      base::OS::Guard(chunk->area_end_, base::OS::CommitPageSize());
+      base::OS::Guard(chunk->area_end_, GetCommitPageSize());
   }
 }
 
 MemoryChunk* MemoryAllocator::AllocateChunk(size_t reserve_area_size,
                                             size_t commit_area_size,
                                             Executability executable,
                                             Space* owner) {
   DCHECK_LE(commit_area_size, reserve_area_size);
 
   size_t chunk_size;
@@ skipping 28 matching lines @@
   // |           Area             |
   // +----------------------------+<- area_end_ (area_start + commit_area_size)
   // |  Committed but not used    |
   // +----------------------------+<- aligned at OS page boundary
   // | Reserved but not committed |
   // +----------------------------+<- base + chunk_size
   //
 
   if (executable == EXECUTABLE) {
     chunk_size = RoundUp(CodePageAreaStartOffset() + reserve_area_size,
-                         base::OS::CommitPageSize()) +
+                         GetCommitPageSize()) +
                  CodePageGuardSize();
 
     // Check executable memory limit.
     if ((size_executable_.Value() + chunk_size) > capacity_executable_) {
       LOG(isolate_, StringEvent("MemoryAllocator::AllocateRawMemory",
                                 "V8 Executable Allocation capacity exceeded"));
       return NULL;
     }
 
     // Size of header (not executable) plus area (executable).
     size_t commit_size = RoundUp(CodePageGuardStartOffset() + commit_area_size,
-                                 base::OS::CommitPageSize());
+                                 GetCommitPageSize());
     // Allocate executable memory either from code range or from the
     // OS.
 #ifdef V8_TARGET_ARCH_MIPS64
     // Use code range only for large object space on mips64 to keep address
     // range within 256-MB memory region.
     if (code_range()->valid() && reserve_area_size > CodePageAreaSize()) {
 #else
     if (code_range()->valid()) {
 #endif
       base =
@@ skipping 15 matching lines @@
 
     if (Heap::ShouldZapGarbage()) {
       ZapBlock(base, CodePageGuardStartOffset());
       ZapBlock(base + CodePageAreaStartOffset(), commit_area_size);
     }
 
     area_start = base + CodePageAreaStartOffset();
     area_end = area_start + commit_area_size;
   } else {
     chunk_size = RoundUp(MemoryChunk::kObjectStartOffset + reserve_area_size,
-                         base::OS::CommitPageSize());
+                         GetCommitPageSize());
     size_t commit_size =
         RoundUp(MemoryChunk::kObjectStartOffset + commit_area_size,
-                base::OS::CommitPageSize());
+                GetCommitPageSize());
     base =
         AllocateAlignedMemory(chunk_size, commit_size, MemoryChunk::kAlignment,
                               executable, &reservation);
 
     if (base == NULL) return NULL;
 
     if (Heap::ShouldZapGarbage()) {
       ZapBlock(base, Page::kObjectStartOffset + commit_area_size);
     }
 
@@ skipping 64 matching lines @@
   // iterate even further.
   while ((filler2->address() + filler2->Size()) != area_end()) {
     filler2 = HeapObject::FromAddress(filler2->address() + filler2->Size());
     DCHECK(filler2->IsFiller());
   }
   DCHECK_EQ(filler->address(), filler2->address());
 #endif  // DEBUG
 
   size_t unused = RoundDown(
       static_cast<size_t>(area_end() - filler->address() - FreeSpace::kSize),
-      base::OS::CommitPageSize());
+      MemoryAllocator::GetCommitPageSize());
   if (unused > 0) {
     if (FLAG_trace_gc_verbose) {
       PrintIsolate(heap()->isolate(), "Shrinking page %p: end %p -> %p\n",
                    reinterpret_cast<void*>(this),
                    reinterpret_cast<void*>(area_end()),
                    reinterpret_cast<void*>(area_end() - unused));
     }
     heap()->CreateFillerObjectAt(
         filler->address(),
         static_cast<int>(area_end() - filler->address() - unused),
@@ skipping 177 matching lines @@
   size_t size = Size();
   float pct = static_cast<float>(capacity_ - size) / capacity_;
   PrintF("  capacity: %zu , used: %" V8PRIdPTR ", available: %%%d\n\n",
          capacity_, size, static_cast<int>(pct * 100));
 }
 #endif
 
 size_t MemoryAllocator::CodePageGuardStartOffset() {
   // We are guarding code pages: the first OS page after the header
   // will be protected as non-writable.
-  return RoundUp(Page::kObjectStartOffset, base::OS::CommitPageSize());
+  return RoundUp(Page::kObjectStartOffset, GetCommitPageSize());
 }
 
 size_t MemoryAllocator::CodePageGuardSize() {
-  return static_cast<int>(base::OS::CommitPageSize());
+  return static_cast<int>(GetCommitPageSize());
 }
 
 size_t MemoryAllocator::CodePageAreaStartOffset() {
   // We are guarding code pages: the first OS page after the header
   // will be protected as non-writable.
   return CodePageGuardStartOffset() + CodePageGuardSize();
 }
 
 size_t MemoryAllocator::CodePageAreaEndOffset() {
   // We are guarding code pages: the last OS page will be protected as
   // non-writable.
-  return Page::kPageSize - static_cast<int>(base::OS::CommitPageSize());
+  return Page::kPageSize - static_cast<int>(GetCommitPageSize());
+}
+
+intptr_t MemoryAllocator::GetCommitPageSize() {
+  if (FLAG_v8_os_page_size != 0) {
+    DCHECK(base::bits::IsPowerOfTwo32(FLAG_v8_os_page_size));
+    return FLAG_v8_os_page_size * KB;
+  } else {
+    return base::OS::CommitPageSize();
+  }
 }
 
 
 bool MemoryAllocator::CommitExecutableMemory(base::VirtualMemory* vm,
                                              Address start, size_t commit_size,
                                              size_t reserved_size) {
   // Commit page header (not executable).
   Address header = start;
   size_t header_size = CodePageGuardStartOffset();
   if (vm->Commit(header, header_size, false)) {
@@ skipping 1844 matching lines @@
 #ifdef VERIFY_HEAP
 void MapSpace::VerifyObject(HeapObject* object) { CHECK(object->IsMap()); }
 #endif
 
 Address LargePage::GetAddressToShrink() {
   HeapObject* object = GetObject();
   if (executable() == EXECUTABLE) {
     return 0;
   }
   size_t used_size = RoundUp((object->address() - address()) + object->Size(),
-                             base::OS::CommitPageSize());
+                             MemoryAllocator::GetCommitPageSize());
   if (used_size < CommittedPhysicalMemory()) {
     return address() + used_size;
   }
   return 0;
 }
 
 void LargePage::ClearOutOfLiveRangeSlots(Address free_start) {
   RememberedSet<OLD_TO_NEW>::RemoveRange(this, free_start, area_end(),
                                          SlotSet::FREE_EMPTY_BUCKETS);
   RememberedSet<OLD_TO_OLD>::RemoveRange(this, free_start, area_end(),
@@ skipping 324 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8