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	If the loop trip count may underflow or wrap, the compiler should not generate a hardware loop since the trip count will be incorrect. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237365 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			23 lines
		
	
	
		
			611 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
			
		
		
	
	
			23 lines
		
	
	
		
			611 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
| ; RUN: llc -march=hexagon -mcpu=hexagonv5 < %s | FileCheck %s
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| 
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| ; We shouldn't generate a hardware loop in this case because the initial
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| ; value may be zero, which means the endloop instruction will not decrement
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| ; the loop counter, and the loop will execute only once.
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| 
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| ; CHECK-NOT: loop0
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| 
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| define void @foo(i32 %count, i32 %v) #0 {
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| entry:
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|   br label %do.body
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| 
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| do.body:
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|   %count.addr.0 = phi i32 [ %count, %entry ], [ %dec, %do.body ]
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|   tail call void asm sideeffect "nop", ""() #1
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|   %dec = add i32 %count.addr.0, -1
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|   %cmp = icmp eq i32 %dec, 0
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|   br i1 %cmp, label %do.end, label %do.body
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| 
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| do.end:
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|   ret void
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| }
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