28 lines
		
	
	
		
			936 B
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			28 lines
		
	
	
		
			936 B
		
	
	
	
		
			LLVM
		
	
	
	
; Test that pure functions are cse'd away
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; RUN: opt < %s -globals-aa -gvn -instcombine -S | FileCheck %s
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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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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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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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