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	This was intended to undo the sub canonicalization in cases where it's not profitable, but it also finds some cases on it's own. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147256 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			38 lines
		
	
	
		
			773 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
			
		
		
	
	
			38 lines
		
	
	
		
			773 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
; RUN: opt -instcombine -S < %s | FileCheck %s
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define i32 @test1(i32 %x) nounwind {
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  %and = and i32 %x, 31
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  %sub = sub i32 63, %and
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  ret i32 %sub
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; CHECK: @test1
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; CHECK-NEXT: and i32 %x, 31
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; CHECK-NEXT: xor i32 %and, 63
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; CHECK-NEXT: ret
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}
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declare i32 @llvm.ctlz.i32(i32, i1) nounwind readnone
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define i32 @test2(i32 %x) nounwind {
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  %count = tail call i32 @llvm.ctlz.i32(i32 %x, i1 true) nounwind readnone
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  %sub = sub i32 31, %count
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  ret i32 %sub
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; CHECK: @test2
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; CHECK-NEXT: ctlz
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; CHECK-NEXT: xor i32 %count, 31
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; CHECK-NEXT: ret
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}
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define i32 @test3(i32 %x) nounwind {
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  %and = and i32 %x, 31
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  %sub = xor i32 31, %and
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  %add = add i32 %sub, 42
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  ret i32 %add
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; CHECK: @test3
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; CHECK-NEXT: and i32 %x, 31
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; CHECK-NEXT: sub i32 73, %and
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; CHECK-NEXT: ret
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}
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