42 lines
		
	
	
		
			898 B
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			42 lines
		
	
	
		
			898 B
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: opt < %s -loop-reduce -S | FileCheck %s
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| 
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| target datalayout = "e-i64:64-v16:16-v32:32-n16:32:64"
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| 
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| ; for (int i = 0; i < n; ++i) {
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| ;   use(i * 5 + 3);
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| ;   // i * a + b is ephemeral and shouldn't be promoted by LSR
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| ;   __builtin_assume(i * a + b >= 0);
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| ; }
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| define void @ephemeral(i32 %a, i32 %b, i32 %n) {
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| ; CHECK-LABEL: @ephemeral(
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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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|   ; Only i and i * 5 + 3 should be indvars, not i * a + b.
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| ; CHECK: phi i32
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| ; CHECK: phi i32
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| ; CHECK-NOT: phi i32
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|   %inc = add nsw i32 %i, 1
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|   %exitcond = icmp eq i32 %inc, %n
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| 
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|   %0 = mul nsw i32 %i, 5
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|   %1 = add nsw i32 %0, 3
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|   call void @use(i32 %1)
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| 
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|   %2 = mul nsw i32 %i, %a
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|   %3 = add nsw i32 %2, %b
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|   %4 = icmp sgt i32 %3, -1
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|   call void @llvm.assume(i1 %4)
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| 
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|   br i1 %exitcond, label %exit, label %loop
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| 
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| exit:
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|   ret void
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| }
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| 
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| declare void @use(i32)
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| 
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| declare void @llvm.assume(i1)
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