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	This patch will optimize abs(x-y) FROM sub, movs, rsbmi TO subs, rsbmi For abs, we will use cmp instead of movs. This is necessary because we already have an existing peephole pass which optimizes away cmp following sub. rdar: 11633193 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158551 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			21 lines
		
	
	
		
			493 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
			
		
		
	
	
			21 lines
		
	
	
		
			493 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
; RUN: llc < %s -march=thumb -mattr=+thumb2 | FileCheck %s
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; PR11107
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define i32 @test(i32 %a, i32 %b) {
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entry:
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; CHECK:        cmp
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; CHECK-NEXT:   it    mi
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; CHECK-NEXT:   rsbmi
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; CHECK-NEXT:   cmp
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; CHECK-NEXT:   it    mi
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; CHECK-NEXT:   rsbmi
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 %cmp1 = icmp slt i32 %a, 0
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 %sub1 = sub nsw i32 0, %a
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 %abs1 = select i1 %cmp1, i32 %sub1, i32 %a
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 %cmp2 = icmp slt i32 %b, 0
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 %sub2 = sub nsw i32 0, %b
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 %abs2 = select i1 %cmp2, i32 %sub2, i32 %b
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 %add = add nsw i32 %abs1, %abs2
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 ret i32 %add
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}
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