29 lines
		
	
	
		
			745 B
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			29 lines
		
	
	
		
			745 B
		
	
	
	
		
			LLVM
		
	
	
	
; RUN: opt < %s -reassociate -instcombine -S | FileCheck %s
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; With sub reassociation, constant folding can eliminate the 12 and -12 constants.
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define i32 @test1(i32 %A, i32 %B) {
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; CHECK-LABEL: @test1(
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; CHECK-NEXT:    [[Z:%.*]] = sub i32 %A, %B
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; CHECK-NEXT:    ret i32 [[Z]]
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;
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  %X = add i32 -12, %A
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  %Y = sub i32 %X, %B
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  %Z = add i32 %Y, 12
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  ret i32 %Z
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}
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; PR2047
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; With sub reassociation, constant folding can eliminate the uses of %a.
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define i32 @test2(i32 %a, i32 %b, i32 %c) {
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; CHECK-LABEL: @test2(
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; CHECK-NEXT:    [[SUM:%.*]] = add i32 %c, %b
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; CHECK-NEXT:    [[TMP7:%.*]] = sub i32 0, [[SUM]]
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; CHECK-NEXT:    ret i32 [[TMP7]]
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;
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  %tmp3 = sub i32 %a, %b
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  %tmp5 = sub i32 %tmp3, %c
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  %tmp7 = sub i32 %tmp5, %a
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  ret i32 %tmp7
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}
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