Remove spills from complex assignments. Some compound assignments now...

src/virtual-frame-ia32.cc

 // Copyright 2008 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 152 matching lines @@
     Spill(result);
     ASSERT(!cgen_->allocator()->is_used(result));
   }
   return result;
 }
 
 
 // Spill an element, making its type be MEMORY.
 // Does not decrement usage counts, if element is a register.
 void VirtualFrame::RawSpillElementAt(int index) {
-  SyncElementAt(index);
-  // The element is now in memory.
-  elements_[index] = FrameElement::MemoryElement();
+  if (elements_[index].is_valid()) {

[Kevin Millikin (Chromium), 2009/02/03 09:48:55]

I think there should also be an early exit in RawSyncElementAt for invalid
elements.

+    SyncElementAt(index);
+    // The element is now in memory.
+    elements_[index] = FrameElement::MemoryElement();
+  }
 }
 
 
 // Make the type of the element at a given index be MEMORY.
 void VirtualFrame::SpillElementAt(int index) {
   if (elements_[index].is_register()) {
     Unuse(elements_[index].reg());
   }
   RawSpillElementAt(index);
 }
@@ skipping 933 matching lines @@
       return false;
     }
   }
   return true;
 }
 #endif
 
 #undef __
 
 } }  // namespace v8::internal