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	present in the bottom of the CFG triangle, as the transformation isn't ever valuable if the branch can't be eliminated. Also, unify some heuristics between SimplifyCFG's multiple if-converters, for consistency. This fixes rdar://10627242. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147630 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			40 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			LLVM
		
	
	
	
	
	
			
		
		
	
	
			40 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			LLVM
		
	
	
	
	
	
| ; RUN: opt -simplifycfg -S < %s | FileCheck %s
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| 
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| ; It's not worthwhile to if-convert one of the phi nodes and leave
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| ; the other behind, because that still requires a branch. If
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| ; SimplifyCFG if-converts one of the phis, it should do both.
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| 
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| ; CHECK:      %div.high.addr.0 = select i1 %cmp1, i32 %div, i32 %high.addr.0
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| ; CHECK-NEXT: %low.0.add2 = select i1 %cmp1, i32 %low.0, i32 %add2
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| ; CHECK-NEXT: br label %while.cond
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| 
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| define i32 @upper_bound(i32* %r, i32 %high, i32 %k) nounwind {
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| entry:
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|   br label %while.cond
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| 
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| while.cond:                                       ; preds = %if.then, %if.else, %entry
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|   %high.addr.0 = phi i32 [ %high, %entry ], [ %div, %if.then ], [ %high.addr.0, %if.else ]
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|   %low.0 = phi i32 [ 0, %entry ], [ %low.0, %if.then ], [ %add2, %if.else ]
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|   %cmp = icmp ult i32 %low.0, %high.addr.0
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|   br i1 %cmp, label %while.body, label %while.end
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| 
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| while.body:                                       ; preds = %while.cond
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|   %add = add i32 %low.0, %high.addr.0
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|   %div = udiv i32 %add, 2
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|   %idxprom = zext i32 %div to i64
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|   %arrayidx = getelementptr inbounds i32* %r, i64 %idxprom
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|   %0 = load i32* %arrayidx
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|   %cmp1 = icmp ult i32 %k, %0
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|   br i1 %cmp1, label %if.then, label %if.else
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| 
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| if.then:                                          ; preds = %while.body
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|   br label %while.cond
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| 
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| if.else:                                          ; preds = %while.body
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|   %add2 = add i32 %div, 1
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|   br label %while.cond
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| 
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| while.end:                                        ; preds = %while.cond
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|   ret i32 %low.0
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| }
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