Start incremental marking on idle notification.

test/cctest/test-heap.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 
 #include <stdlib.h>
 
 #include "v8.h"
 
 #include "execution.h"
 #include "factory.h"
 #include "macro-assembler.h"
 #include "global-handles.h"
@@ skipping 1271 matching lines @@
   intptr_t old_capacity, new_capacity;
   old_capacity = new_space->Capacity();
   new_space->Grow();
   new_capacity = new_space->Capacity();
   CHECK(2 * old_capacity == new_capacity);
   FillUpNewSpace(new_space);
   HEAP->CollectAllAvailableGarbage();
   new_capacity = new_space->Capacity();
   CHECK(old_capacity == new_capacity);
 }
+
+
+TEST(IdleNotificationAdvancesIncrementalMarking) {
+  if (!FLAG_incremental_marking || !FLAG_incremental_marking_steps) return;
+  InitializeVM();
+  v8::HandleScope scope;
+  const char* source = "function binom(n, m) {"
+                       "  var C = [[1]];"
+                       "  for (var i = 1; i <= n; ++i) {"
+                       "    C[i] = [1];"
+                       "    for (var j = 1; j < i; ++j) {"
+                       "      C[i][j] = C[i-1][j-1] + C[i-1][j];"
+                       "    }"
+                       "    C[i][i] = 1;"
+                       "  }"
+                       "  return C[n][m];"
+                       "};"
+                       "binom(1000, 500)";
+  {
+    AlwaysAllocateScope aa_scope;
+    CompileRun(source);
+  }
+  if (HEAP->incremental_marking()->IsStopped()) {
+    HEAP->incremental_marking()->Start();
+  }
+  intptr_t old_size = HEAP->SizeOfObjects();
+  while (!v8::V8::IdleNotification());
+  intptr_t new_size = HEAP->SizeOfObjects();
+  CHECK(new_size < old_size);

[Erik Corry, 2011/11/25 09:21:30]

Can we tighten this assertion?   It should have collected a lot of memory by
this time.  Perhaps we can insist that it has collected half?

+}