[heap] refactor inline allocation step code

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 "src/base/bits.h"
 #include "src/base/platform/platform.h"
 #include "src/full-codegen/full-codegen.h"
 #include "src/heap/slots-buffer.h"
@@ skipping 1382 matching lines @@
 void NewSpace::ResetAllocationInfo() {
   Address old_top = allocation_info_.top();
   to_space_.Reset();
   UpdateAllocationInfo();
   pages_used_ = 0;
   // Clear all mark-bits in the to-space.
   NewSpacePageIterator it(&to_space_);
   while (it.has_next()) {
     Bitmap::Clear(it.next());
   }
-  if (top_on_previous_step_) {
-    int bytes_allocated = static_cast<int>(old_top - top_on_previous_step_);
-    heap()->incremental_marking()->Step(bytes_allocated,
-                                        IncrementalMarking::GC_VIA_STACK_GUARD);
-    top_on_previous_step_ = allocation_info_.top();
-  }
+  InlineAllocationStep(old_top, allocation_info_.top());
 }
 
 
 void NewSpace::UpdateInlineAllocationLimit(int size_in_bytes) {
   if (heap()->inline_allocation_disabled()) {
     // Lowest limit when linear allocation was disabled.
     Address high = to_space_.page_high();
     Address new_top = allocation_info_.top() + size_in_bytes;
     allocation_info_.set_limit(Min(new_top, high));
   } else if (inline_allocation_limit_step() == 0) {
@@ skipping 58 matching lines @@
   Address high = to_space_.page_high();
   int filler_size = Heap::GetFillToAlign(old_top, alignment);
   int aligned_size_in_bytes = size_in_bytes + filler_size;
 
   if (old_top + aligned_size_in_bytes >= high) {
     // Not enough room in the page, try to allocate a new one.
     if (!AddFreshPage()) {
       return false;
     }
 
-    if (top_on_previous_step_) {
-      // Do a step for the bytes allocated on the last page.
-      int bytes_allocated = static_cast<int>(old_top - top_on_previous_step_);
-      heap()->incremental_marking()->Step(
-          bytes_allocated, IncrementalMarking::GC_VIA_STACK_GUARD);
-      top_on_previous_step_ = allocation_info_.top();
-    }
+    InlineAllocationStep(old_top, allocation_info_.top());
 
     old_top = allocation_info_.top();
     high = to_space_.page_high();
     filler_size = Heap::GetFillToAlign(old_top, alignment);
     aligned_size_in_bytes = size_in_bytes + filler_size;
   }
 
   DCHECK(old_top + aligned_size_in_bytes < high);
 
   if (allocation_info_.limit() < high) {
     // Either the limit has been lowered because linear allocation was disabled
     // or because incremental marking wants to get a chance to do a step. Set
     // the new limit accordingly.
-    if (top_on_previous_step_) {
-      Address new_top = old_top + aligned_size_in_bytes;
-      int bytes_allocated = static_cast<int>(new_top - top_on_previous_step_);
-      heap()->incremental_marking()->Step(
-          bytes_allocated, IncrementalMarking::GC_VIA_STACK_GUARD);
-      top_on_previous_step_ = new_top;
-    }
+    Address new_top = old_top + aligned_size_in_bytes;
+    InlineAllocationStep(new_top, new_top);
     UpdateInlineAllocationLimit(aligned_size_in_bytes);
   }
   return true;
 }
 
 
+void NewSpace::InlineAllocationStep(Address top, Address new_top) {
+  if (top_on_previous_step_) {
+    int bytes_allocated = static_cast<int>(top - top_on_previous_step_);
+    heap()->incremental_marking()->Step(bytes_allocated,
+                                        IncrementalMarking::GC_VIA_STACK_GUARD);
+    top_on_previous_step_ = new_top;
+  }
+}
+
 #ifdef VERIFY_HEAP
 // We do not use the SemiSpaceIterator because verification doesn't assume
 // that it works (it depends on the invariants we are checking).
 void NewSpace::Verify() {
   // The allocation pointer should be in the space or at the very end.
   DCHECK_SEMISPACE_ALLOCATION_INFO(allocation_info_, to_space_);
 
   // There should be objects packed in from the low address up to the
   // allocation pointer.
   Address current = to_space_.first_page()->area_start();
@@ skipping 1614 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8