Fix http://code.google.com/p/v8/issues/detail?id=69 :...

src/codegen-ia32.cc

 // Copyright 2006-2008 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 2899 matching lines @@
   Label next, fall_through, default_case;
   ZoneList<CaseClause*>* cases = node->cases();
   int length = cases->length();
 
   for (int i = 0; i < length; i++) {
     CaseClause* clause = cases->at(i);
 
     Comment cmnt(masm_, "[ case clause");
 
     if (clause->is_default()) {
+      // Continue matching cases. The program will execute the default case's
+      // statements if it does not match any of the cases.
+      __ jmp(&next);
+
       // Bind the default case label, so we can branch to it when we
       // have compared against all other cases.
       ASSERT(default_case.is_unused());  // at most one default clause
-
-      // If the default case is the first (but not only) case, we have
-      // to jump past it for now. Once we're done with the remaining
-      // clauses, we'll branch back here. If it isn't the first case,
-      // we jump past it by avoiding to chain it into the next chain.
-      if (length > 1) {
-        if (i == 0) __ jmp(&next);
-        __ bind(&default_case);
-      }
-
+      __ bind(&default_case);
     } else {
       __ bind(&next);
       next.Unuse();
       __ mov(eax, TOS);
       __ push(eax);  // duplicate TOS
       Load(clause->label());
       Comparison(equal, true);
       Branch(false, &next);
-      // Entering the case statement -> remove the switch value from the stack
-      __ pop(eax);
     }
 
+    // Entering the case statement for the first time. Remove the switch value
+    // from the stack.
+    __ pop(eax);
+
     // Generate code for the body.
+    // This is also the target for the fall through from the previous case's
+    // statements which has to skip over the matching code and the popping of
+    // the switch value.
     __ bind(&fall_through);
     fall_through.Unuse();
     VisitStatements(clause->statements());
     __ jmp(&fall_through);
   }
 
   __ bind(&next);
-  // Reached the end of the case statements -> remove the switch value
-  // from the stack
-  __ pop(eax);  // Pop(no_reg)
-  if (default_case.is_bound()) __ jmp(&default_case);
+  // Reached the end of the case statements without matching any of the cases.
+  if (default_case.is_bound()) {
+    // A default case exists -> execute its statements.
+    __ jmp(&default_case);
+  } else {
+    // Remove the switch value from the stack.
+    __ pop(eax);
+  }
 
   __ bind(&fall_through);
   __ bind(node->break_target());
 }
 
 
 void Ia32CodeGenerator::VisitLoopStatement(LoopStatement* node) {
   Comment cmnt(masm_, "[ LoopStatement");
   if (FLAG_debug_info) RecordStatementPosition(node);
   node->set_break_stack_height(break_stack_height_);
@@ skipping 2428 matching lines @@
                                      bool is_eval) {
   Handle<Code> code = Ia32CodeGenerator::MakeCode(fun, script, is_eval);
   if (!code.is_null()) {
     Counters::total_compiled_code_size.Increment(code->instruction_size());
   }
   return code;
 }
 
 
 } }  // namespace v8::internal