31 lines
		
	
	
		
			746 B
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			31 lines
		
	
	
		
			746 B
		
	
	
	
		
			LLVM
		
	
	
	
; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
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; CHECK: @f
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; CHECK: Loop %bb16.preheader: backedge-taken count is (-1 + %c.idx.val)
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define i32 @f(i32 %c.idx.val) {
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bb2:
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	%k.018 = add i32 %c.idx.val, -1		; <i32> [#uses=2]
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	%a14 = icmp slt i32 %k.018, 0		; <i1> [#uses=1]
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	br i1 %a14, label %bb19, label %bb16.preheader
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bb16.preheader:
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	%k.019 = phi i32 [ %k.0, %bb18 ], [ %k.018, %bb2 ]		; <i32> [#uses=5]
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	%x = phi i32 [ 0, %bb2 ], [ %x.1, %bb18]
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	br label %bb18
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bb18:		; preds = %bb18.loopexit
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	%x.1 = add i32 %x, 1
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	%k.0 = add i32 %k.019, -1		; <i32> [#uses=2]
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	%a107 = icmp slt i32 %k.0, 0		; <i1> [#uses=1]
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	br i1 %a107, label %bb18.bb19_crit_edge, label %bb16.preheader
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bb18.bb19_crit_edge:
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	ret i32 %x
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bb19:
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	ret i32 0
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}
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