remove recursion from NewSpace::AllocateRaw*

src/heap/spaces-inl.h

 // 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.
 
 #ifndef V8_HEAP_SPACES_INL_H_
 #define V8_HEAP_SPACES_INL_H_
 
 #include "src/heap/spaces.h"
 #include "src/heap-profiler.h"
 #include "src/isolate.h"
@@ skipping 327 matching lines @@
 #endif
 }
 
 
 // -----------------------------------------------------------------------------
 // NewSpace
 
 
 AllocationResult NewSpace::AllocateRawAligned(int size_in_bytes,
                                               AllocationAlignment alignment) {
-  Address old_top = allocation_info_.top();
-  int filler_size = Heap::GetFillToAlign(old_top, alignment);
+  int filler_size = Heap::GetFillToAlign(allocation_info_.top(), alignment);

[Hannes Payer (out of office), 2015/07/30 10:38:25]

Keep top in a temporary variable.

[ofrobots, 2015/07/30 20:26:17]

Done.

   int aligned_size_in_bytes = size_in_bytes + filler_size;
 
-  if (allocation_info_.limit() - old_top < aligned_size_in_bytes) {
-    return SlowAllocateRaw(size_in_bytes, alignment);
+  if (allocation_info_.limit() - allocation_info_.top() <
+      aligned_size_in_bytes) {
+    // See if we can create room.
+    if (EnsureAllocation(size_in_bytes, alignment) == false) {

[Hannes Payer (out of office), 2015/07/30 10:38:25]

Instead of "== false" use "!".

[ofrobots, 2015/07/30 20:26:17]

Done.

+      return AllocationResult::Retry();
+    }
+

[Hannes Payer (out of office), 2015/07/30 10:38:25]

if top changed, read out top again and recalculate aligned_size_in_bytes.

[ofrobots, 2015/07/30 20:26:17]

Done.

+    if (allocation_info_.limit() - allocation_info_.top() <
+        aligned_size_in_bytes) {

[Hannes Payer (out of office), 2015/07/30 10:38:25]

This check should not be needed.

[ofrobots, 2015/07/30 20:26:17]

Done.

+      // Still not enough room.
+      return AllocationResult::Retry();
+    }
   }
 
-  HeapObject* obj = HeapObject::FromAddress(old_top);
+  HeapObject* obj = HeapObject::FromAddress(allocation_info_.top());

[Hannes Payer (out of office), 2015/07/30 10:38:25]

Use the temporary top variable here.

[ofrobots, 2015/07/30 20:26:17]

Done.

   allocation_info_.set_top(allocation_info_.top() + aligned_size_in_bytes);
   DCHECK_SEMISPACE_ALLOCATION_INFO(allocation_info_, to_space_);
 
   if (filler_size > 0) {
     obj = heap()->PrecedeWithFiller(obj, filler_size);
   }
 
-  // The slow path above ultimately goes through AllocateRaw, so this suffices.
   MSAN_ALLOCATED_UNINITIALIZED_MEMORY(obj->address(), size_in_bytes);
 
   return obj;
 }
 
 
 AllocationResult NewSpace::AllocateRawUnaligned(int size_in_bytes) {

[Hannes Payer (out of office), 2015/07/30 10:38:25]

Comments from above apply also here.

[ofrobots, 2015/07/30 20:26:16]

Done.

-  Address old_top = allocation_info_.top();
+  if (allocation_info_.limit() - allocation_info_.top() < size_in_bytes) {
+    // See if we can create room.
+    if (EnsureAllocation(size_in_bytes, kWordAligned) == false) {
+      return AllocationResult::Retry();
+    }
 
-  if (allocation_info_.limit() - old_top < size_in_bytes) {
-    return SlowAllocateRaw(size_in_bytes, kWordAligned);
+    if (allocation_info_.limit() - allocation_info_.top() < size_in_bytes) {
+      // Still not enough room.
+      return AllocationResult::Retry();
+    }
   }
 
-  HeapObject* obj = HeapObject::FromAddress(old_top);
+  HeapObject* obj = HeapObject::FromAddress(allocation_info_.top());
   allocation_info_.set_top(allocation_info_.top() + size_in_bytes);
   DCHECK_SEMISPACE_ALLOCATION_INFO(allocation_info_, to_space_);
 
-  // The slow path above ultimately goes through AllocateRaw, so this suffices.
   MSAN_ALLOCATED_UNINITIALIZED_MEMORY(obj->address(), size_in_bytes);
 
   return obj;
 }
 
 
 AllocationResult NewSpace::AllocateRaw(int size_in_bytes,
                                        AllocationAlignment alignment) {
 #ifdef V8_HOST_ARCH_32_BIT
   return alignment == kDoubleAligned
@@ skipping 12 matching lines @@
 
 
 intptr_t LargeObjectSpace::Available() {
   return ObjectSizeFor(heap()->isolate()->memory_allocator()->Available());
 }
 
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_SPACES_INL_H_