28 lines
		
	
	
		
			953 B
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			28 lines
		
	
	
		
			953 B
		
	
	
	
		
			LLVM
		
	
	
	
| ; Test that pure functions are cse'd away
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| ; RUN: opt < %s -disable-basicaa -globals-aa -gvn -instcombine -S | FileCheck %s
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| 
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| define i32 @pure(i32 %X) {
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|         %Y = add i32 %X, 1              ; <i32> [#uses=1]
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|         ret i32 %Y
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| }
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| 
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| define i32 @test1(i32 %X) {
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| ; CHECK:      %A = call i32 @pure(i32 %X)
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| ; CHECK-NEXT: ret i32 0
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|         %A = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
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|         %B = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
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|         %C = sub i32 %A, %B             ; <i32> [#uses=1]
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|         ret i32 %C
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| }
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| 
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| define i32 @test2(i32 %X, i32* %P) {
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| ; CHECK:      %A = call i32 @pure(i32 %X)
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| ; CHECK-NEXT: store i32 %X, i32* %P
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| ; CHECK-NEXT: ret i32 0
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|         %A = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
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|         store i32 %X, i32* %P ;; Does not invalidate 'pure' call.
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|         %B = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
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|         %C = sub i32 %A, %B             ; <i32> [#uses=1]
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|         ret i32 %C
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| }
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