Add counters for write barriers in optimized code.

src/ia32/macro-assembler-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 571 matching lines @@
 
   ASSERT(!object.is(value));
   ASSERT(!object.is(address));
   ASSERT(!value.is(address));
   AssertNotSmi(object);
 
   if (!FLAG_incremental_marking) {
     return;
   }
 
+  // Count number of write barriers in generated code.
+  isolate()->counters()->write_barriers_static()->Increment();
+  IncrementCounter(isolate()->counters()->write_barriers_dynamic(), 1);
+
   // A single check of the map's pages interesting flag suffices, since it is
   // only set during incremental collection, and then it's also guaranteed that
   // the from object's page's interesting flag is also set.  This optimization
   // relies on the fact that maps can never be in new space.
   ASSERT(!isolate()->heap()->InNewSpace(*map));
   CheckPageFlagForMap(map,
                       MemoryChunk::kPointersToHereAreInterestingMask,
                       zero,
                       &done,
                       Label::kNear);
@@ skipping 36 matching lines @@
   }
 
   if (emit_debug_code()) {
     Label ok;
     cmp(value, Operand(address, 0));
     j(equal, &ok, Label::kNear);
     int3();
     bind(&ok);
   }
 
+  // Count number of write barriers in generated code.
+  isolate()->counters()->write_barriers_static()->Increment();
+  IncrementCounter(isolate()->counters()->write_barriers_dynamic(), 1);
+
   // First, check if a write barrier is even needed. The tests below
   // catch stores of Smis and stores into young gen.
   Label done;
 
   if (smi_check == INLINE_SMI_CHECK) {
     // Skip barrier if writing a smi.
     JumpIfSmi(value, &done, Label::kNear);
   }
 
   CheckPageFlag(value,
@@ skipping 2870 matching lines @@
   j(greater, &no_memento_available);
   cmp(MemOperand(scratch_reg, -AllocationMemento::kSize),
       Immediate(isolate()->factory()->allocation_memento_map()));
   bind(&no_memento_available);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32