Moves the top_ and end_ words of the Scavenger into mutator thread.

runtime/vm/heap.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/heap.h"
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/flags.h"
 #include "vm/isolate.h"
@@ skipping 45 matching lines @@
     delete new_weak_tables_[sel];
     delete old_weak_tables_[sel];
   }
 }
 
 
 uword Heap::AllocateNew(intptr_t size) {
   ASSERT(Thread::Current()->no_safepoint_scope_depth() == 0);
   // Currently, only the Dart thread may allocate in new space.
   isolate()->AssertCurrentThreadIsMutator();
-  uword addr = new_space_.TryAllocate(size);
+  uword addr = new_space_.TryAllocateInTLAB(Thread::Current(), size);

[rmacnak, 2017/07/12 20:30:06]

Hoist Thread::Current() so it is only called once.

[danunez, 2017/07/12 21:02:12]

Done.

   if (addr == 0) {
     // This call to CollectGarbage might end up "reusing" a collection spawned
     // from a different thread and will be racing to allocate the requested
     // memory with other threads being released after the collection.
     CollectGarbage(kNew);
-    addr = new_space_.TryAllocate(size);
+    addr = new_space_.TryAllocateInTLAB(Thread::Current(), size);
     if (addr == 0) {
       return AllocateOld(size, HeapPage::kData);
     }
   }
   return addr;
 }
 
 
 uword Heap::AllocateOld(intptr_t size, HeapPage::PageType type) {
   ASSERT(Thread::Current()->no_safepoint_scope_depth() == 0);
@@ skipping 419 matching lines @@
 }
 
 
 void Heap::WriteProtect(bool read_only) {
   read_only_ = read_only;
   new_space_.WriteProtect(read_only);
   old_space_.WriteProtect(read_only);
 }
 
 
-intptr_t Heap::TopOffset(Heap::Space space) {
-  if (space == kNew) {
-    return OFFSET_OF(Heap, new_space_) + Scavenger::top_offset();
-  } else {
-    ASSERT(space == kOld);
-    return OFFSET_OF(Heap, old_space_) + PageSpace::top_offset();
-  }
-}
-
-
-intptr_t Heap::EndOffset(Heap::Space space) {
-  if (space == kNew) {
-    return OFFSET_OF(Heap, new_space_) + Scavenger::end_offset();
-  } else {
-    ASSERT(space == kOld);
-    return OFFSET_OF(Heap, old_space_) + PageSpace::end_offset();
-  }
-}
-
-
 void Heap::Init(Isolate* isolate,
                 intptr_t max_new_gen_words,
                 intptr_t max_old_gen_words,
                 intptr_t max_external_words) {
   ASSERT(isolate->heap() == NULL);
   Heap* heap = new Heap(isolate, max_new_gen_words, max_old_gen_words,
                         max_external_words);
   isolate->set_heap(heap);
 }
 
@@ skipping 58 matching lines @@
 
 
 bool Heap::Verify(MarkExpectation mark_expectation) const {
   HeapIterationScope heap_iteration_scope;
   return VerifyGC(mark_expectation);
 }
 
 
 bool Heap::VerifyGC(MarkExpectation mark_expectation) const {
   StackZone stack_zone(Thread::Current());
+
+  // Change the new space's top_ with the more up-to-date thread's view of top_
+  new_space_.FlushTLS();
+
   ObjectSet* allocated_set =
       CreateAllocatedObjectSet(stack_zone.GetZone(), mark_expectation);
   VerifyPointersVisitor visitor(isolate(), allocated_set);
   VisitObjectPointers(&visitor);
 
   // Only returning a value so that Heap::Validate can be called from an ASSERT.
   return true;
 }
 
 
@@ skipping 278 matching lines @@
   Dart::vm_isolate()->heap()->WriteProtect(false);
 }
 
 
 WritableVMIsolateScope::~WritableVMIsolateScope() {
   ASSERT(Dart::vm_isolate()->heap()->UsedInWords(Heap::kNew) == 0);
   Dart::vm_isolate()->heap()->WriteProtect(true);
 }
 
 }  // namespace dart