54 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			54 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: opt < %s -S -loop-unroll -unroll-threshold=4 | FileCheck %s
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| 
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| define i32 @invariant_backedge_1(i32 %a, i32 %b) {
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| ; CHECK-LABEL: @invariant_backedge_1
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| ; CHECK-NOT:     %plus = phi
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| ; CHECK:       loop.peel:
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| ; CHECK:       loop:
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| ; CHECK:         %i = phi
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| ; CHECK:         %sum = phi
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| entry:
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|   br label %loop
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| 
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| loop:
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|   %i = phi i32 [ 0, %entry ], [ %inc, %loop ]
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|   %sum = phi i32 [ 0, %entry ], [ %incsum, %loop ]
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|   %plus = phi i32 [ %a, %entry ], [ %b, %loop ]
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| 
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|   %incsum = add i32 %sum, %plus
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|   %inc = add i32 %i, 1
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|   %cmp = icmp slt i32 %i, 1000
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| 
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|   br i1 %cmp, label %loop, label %exit
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| 
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| exit:
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|   ret i32 %sum
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| }
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| 
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| ; Peeling should fail due to method size.
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| define i32 @invariant_backedge_2(i32 %a, i32 %b) {
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| ; CHECK-LABEL: @invariant_backedge_2
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| ; CHECK-NOT:   loop.peel:
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| ; CHECK:       loop:
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| ; CHECK:         %i = phi
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| ; CHECK:         %sum = phi
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| ; CHECK:         %plus = phi
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| entry:
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|   br label %loop
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| 
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| loop:
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|   %i = phi i32 [ 0, %entry ], [ %inc, %loop ]
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|   %sum = phi i32 [ 0, %entry ], [ %incsum2, %loop ]
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|   %plus = phi i32 [ %a, %entry ], [ %b, %loop ]
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| 
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|   %incsum = add i32 %sum, %plus
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|   %incsum2 = add i32 %incsum, %plus
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|   %inc = add i32 %i, 1
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|   %cmp = icmp slt i32 %i, 1000
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| 
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|   br i1 %cmp, label %loop, label %exit
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| 
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| exit:
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|   ret i32 %sum
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| }
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