35 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			35 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: opt -indvars < %s
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| ; PR9424: Attempt to use a SCEVCouldNotCompute object!
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| ; The inner loop computes the Step and Start of the outer loop.
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| ; Call that Vexit. The outer End value is max(2,Vexit), because
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| ; the condition "icmp %4 < 2" does not guard the outer loop.
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| ; SCEV knows that Vexit has range [2,4], so End == Vexit == Start.
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| ; Now we have ExactBECount == 0. However, MinStart == 2 and MaxEnd == 4.
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| ; Since the stride is variable and may wrap, we cannot compute
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| ; MaxBECount. SCEV should override MaxBECount with ExactBECount.
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| 
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| define void @bar() nounwind {
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| entry:
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|   %. = select i1 undef, i32 2, i32 1
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|   br label %"5.preheader"
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| 
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| "4":                                              ; preds = %"5.preheader", %"4"
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|   %0 = phi i32 [ 0, %"5.preheader" ], [ %1, %"4" ]
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|   %1 = add nsw i32 %0, 1
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|   %2 = icmp sgt i32 %., %1
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|   br i1 %2, label %"4", label %"9"
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| 
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| "9":                                              ; preds = %"4"
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|   %3 = add i32 %6, 1
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|   %4 = add i32 %3, %1
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|   %5 = icmp slt i32 %4, 2
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|   br i1 %5, label %"5.preheader", label %return
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| 
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| "5.preheader":                                    ; preds = %"9", %entry
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|   %6 = phi i32 [ 0, %entry ], [ %4, %"9" ]
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|   br label %"4"
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| 
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| return:                                           ; preds = %"9"
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|   ret void
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| }
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