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			38 lines
		
	
	
		
			559 B
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			38 lines
		
	
	
		
			559 B
		
	
	
	
		
			Python
		
	
	
	
	
	
| from rule import Rule
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| from opcodes import *
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| 
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| """
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| Rule:
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| MUL(X, A) -> SHL(k, X)
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| MUL(A, X) -> SHL(k, X)
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| DIV(X, A) -> SHR(k, X)
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| Requirements:
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| A == 1 << K
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| """
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| 
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| rule = Rule()
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| 
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| n_bits = 32
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| 
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| # Input vars
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| X = BitVec('X', n_bits)
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| A = BitVec('A', n_bits)
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| K = BitVec('K', n_bits)
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| 
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| # Requirements
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| rule.require(A == SHL(K, 1))
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| 
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| # Non optimized result
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| nonopt_1 = MUL(X, A)
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| nonopt_2 = MUL(A, X)
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| nonopt_3 = DIV(X, A)
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| 
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| # Optimized result
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| opt_1 = SHL(K, X)
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| opt_2 = SHL(K, X)
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| opt_3 = SHR(K, X)
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| 
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| rule.check(nonopt_1, opt_1)
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| rule.check(nonopt_2, opt_2)
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| rule.check(nonopt_3, opt_3)
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