- Introduce a synchronous GC before throwing OOM.

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 71 matching lines @@
   ASSERT(isolate()->no_gc_scope_depth() == 0);
   uword addr = old_space_->TryAllocate(size, type);
   if (addr != 0) {
     return addr;
   }
   // If we are in the process of running a sweep wait for the sweeper to free
   // memory.
   {
     MonitorLocker ml(old_space_->tasks_lock());
     addr = old_space_->TryAllocate(size, type);
-    while ((addr == 0) && (old_space_->tasks())) {
+    while ((addr == 0) && (old_space_->tasks() > 0)) {
       ml.Wait();
       addr = old_space_->TryAllocate(size, type);
     }
   }
   if (addr != 0) {
     return addr;
   }
-  // All GC tasks finished without allocating successfully. Run a full GC.
-  CollectAllGarbage();
-  addr = old_space_->TryAllocate(size, type, PageSpace::kForceGrowth);
+  // All GC tasks finished without allocating successfully. Run an old GC.
+  CollectGarbage(kOld);
+  addr = old_space_->TryAllocate(size, type);
   if (addr != 0) {
     return addr;
   }
   // Wait for all of the concurrent tasks to finish before giving up.
   {
     MonitorLocker ml(old_space_->tasks_lock());
-    addr = old_space_->TryAllocate(size, type, PageSpace::kForceGrowth);
-    while ((addr == 0) && (old_space_->tasks())) {
+    addr = old_space_->TryAllocate(size, type);
+    while ((addr == 0) && (old_space_->tasks() > 0)) {
       ml.Wait();
-      addr = old_space_->TryAllocate(size, type, PageSpace::kForceGrowth);
+      addr = old_space_->TryAllocate(size, type);
     }
   }
   if (addr != 0) {
     return addr;
   }
-  // Giving up allocating this object.
+  // Force growth before attempting a synchronous GC.
+  addr = old_space_->TryAllocate(size, type, PageSpace::kForceGrowth);
+  if (addr != 0) {
+    return addr;
+  }
+  // Before throwing an out-of-memory error try a synchronous GC.
+  CollectAllGarbage();
+  {
+    MonitorLocker ml(old_space_->tasks_lock());
+    while (old_space_->tasks() > 0) {
+      ml.Wait();
+    }
+  }
+  addr = old_space_->TryAllocate(size, type, PageSpace::kForceGrowth);
+  if (addr != 0) {
+    return addr;
+  }
+  // Give up allocating this object.
   OS::PrintErr(
       "Exhausted heap space, trying to allocate %" Pd " bytes.\n", size);
   return 0;
 }
 
 void Heap::AllocateExternal(intptr_t size, Space space) {
   ASSERT(isolate()->no_gc_scope_depth() == 0);
   if (space == kNew) {
     new_space_->AllocateExternal(size);
     if (new_space_->ExternalInWords() > (FLAG_new_gen_ext_limit * MBInWords)) {
@@ skipping 501 matching lines @@
     heap->DisableGrowthControl();
 }
 
 
 NoHeapGrowthControlScope::~NoHeapGrowthControlScope() {
     Heap* heap = reinterpret_cast<Isolate*>(isolate())->heap();
     heap->SetGrowthControlState(current_growth_controller_state_);
 }
 
 }  // namespace dart