35 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			35 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			LLVM
		
	
	
	
; RUN: opt < %s -instcombine -S | FileCheck %s
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%struct.C = type { %struct.C*, i32 }
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; Check that we instcombine the load across the prefetch.
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; CHECK-LABEL: define signext i32 @foo
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define signext i32 @foo(%struct.C* %c) local_unnamed_addr #0 {
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; CHECK: store i32 %dec, i32* %length_
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; CHECK-NOT: load
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; CHECK: llvm.prefetch
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; CHECK-NEXT: ret
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entry:
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  %next_ = getelementptr inbounds %struct.C, %struct.C* %c, i32 0, i32 0
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  %0 = load %struct.C*, %struct.C** %next_, align 8
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  %next_1 = getelementptr inbounds %struct.C, %struct.C* %0, i32 0, i32 0
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  %1 = load %struct.C*, %struct.C** %next_1, align 8
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  store %struct.C* %1, %struct.C** %next_, align 8
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  %length_ = getelementptr inbounds %struct.C, %struct.C* %c, i32 0, i32 1
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  %2 = load i32, i32* %length_, align 8
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  %dec = add nsw i32 %2, -1
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  store i32 %dec, i32* %length_, align 8
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  %3 = bitcast %struct.C* %1 to i8*
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  call void @llvm.prefetch(i8* %3, i32 0, i32 0, i32 1)
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  %4 = load i32, i32* %length_, align 8
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  ret i32 %4
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}
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; Function Attrs: inaccessiblemem_or_argmemonly nounwind
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declare void @llvm.prefetch(i8* nocapture readonly, i32, i32, i32) 
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attributes #0 = { noinline nounwind }
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; We've explicitly removed the function attrs from llvm.prefetch so we get the defaults.
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; attributes #1 = { inaccessiblemem_or_argmemonly nounwind }
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