While allocating code objects, perform the incremental marking step before...

While allocating code objects, perform the incremental marking step before NULLing the new object. Otherwise the code cache cannot iterate the code space anymore, which is required to clear ICs.

Review URL: https://chromiumcodereview.appspot.com/10834408

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12345 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/spaces.cc

@@ -2027,15 +2027,16 @@ HeapObject* FreeList::Allocate(int size_in_bytes) {
   // if it is big enough.
   owner_->Free(owner_->top(), old_linear_size);
 
+  owner_->heap()->incremental_marking()->OldSpaceStep(
+      size_in_bytes - old_linear_size);
+
 #ifdef DEBUG
   for (int i = 0; i < size_in_bytes / kPointerSize; i++) {
-    reinterpret_cast<Object**>(new_node->address())[i] = Smi::FromInt(0);
+    reinterpret_cast<Object**>(new_node->address())[i] =
+        Smi::FromInt(kCodeZapValue);
   }
 #endif
 
-  owner_->heap()->incremental_marking()->OldSpaceStep(
-      size_in_bytes - old_linear_size);
-
   // The old-space-step might have finished sweeping and restarted marking.
   // Verify that it did not turn the page of the new node into an evacuation
   // candidate.

src/v8globals.h

@@ -94,6 +94,7 @@ const uint32_t kDebugZapValue = 0xbadbaddb;
 const uint32_t kFreeListZapValue = 0xfeed1eaf;
 #endif
 
+const int kCodeZapValue = 0xbadc0de;
 
 // Number of bits to represent the page size for paged spaces. The value of 20
 // gives 1Mb bytes per page.