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			26 lines
		
	
	
		
			824 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			26 lines
		
	
	
		
			824 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| // Copyright 2015 the V8 project authors. All rights reserved.
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| // Use of this source code is governed by a BSD-style license that can be
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| // found in the LICENSE file.
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| 
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| // Flags: --allow-natives-syntax --no-stress-opt --opt --no-always-opt
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| 
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| // --nostress-opt is specified because the test corrupts the "pristine"
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| // array prototype chain by storing an element, and this is tracked
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| // per-isolate. A subsequent stress run would send the load generic,
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| // and no more deoptimizations of foo would occur.
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| 
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| function foo(a, i) { return a[i]; }
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| 
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| var a = ['one', , 'three'];
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| foo(a, 0);
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| foo(a, 0);
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| foo(a, 0);
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| %OptimizeFunctionOnNextCall(foo);
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| assertEquals(undefined, foo(a, 1));
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| assertOptimized(foo);
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| 
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| // Whereas if we disrupt the prototype chain...
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| Array.prototype[1] = 'cow';
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| assertEquals('cow', foo(a, 1));
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| assertUnoptimized(foo);
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