forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			55 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			55 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: opt -basicaa -loop-load-elim -S < %s | FileCheck %s
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| 
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| target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
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| 
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| ; Give up in the presence of unknown deps. Here, the different strides result
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| ; in unknown dependence:
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| ;
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| ;   for (unsigned i = 0; i < 100; i++) {
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| ;     A[i+1] = B[i] + 2;
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| ;     A[2*i] = C[i] + 2;
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| ;     D[i] = A[i] + 2;
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| ;   }
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| 
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| define void @f(i32* noalias %A, i32* noalias %B, i32* noalias %C,
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|                i32* noalias %D, i64 %N) {
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| 
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| entry:
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| ; for.body.ph:
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| ; CHECK-NOT: %load_initial =
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|   br label %for.body
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| 
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| for.body:                                         ; preds = %for.body, %entry
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| ; CHECK-NOT: %store_forwarded =
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|   %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
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|   %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
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| 
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|   %Aidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next
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|   %Bidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
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|   %Cidx = getelementptr inbounds i32, i32* %C, i64 %indvars.iv
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|   %Didx = getelementptr inbounds i32, i32* %D, i64 %indvars.iv
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|   %Aidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
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|   %indvars.m2 = mul nuw nsw i64 %indvars.iv, 2
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|   %A2idx = getelementptr inbounds i32, i32* %A, i64 %indvars.m2
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| 
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|   %b = load i32, i32* %Bidx, align 4
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|   %a_p1 = add i32 %b, 2
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|   store i32 %a_p1, i32* %Aidx_next, align 4
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| 
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|   %c = load i32, i32* %Cidx, align 4
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|   %a_m2 = add i32 %c, 2
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|   store i32 %a_m2, i32* %A2idx, align 4
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| 
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|   %a = load i32, i32* %Aidx, align 4
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| ; CHECK-NOT: %d = add i32 %store_forwarded, 2
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| ; CHECK: %d = add i32 %a, 2
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|   %d = add i32 %a, 2
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|   store i32 %d, i32* %Didx, align 4
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| 
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|   %exitcond = icmp eq i64 %indvars.iv.next, %N
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|   br i1 %exitcond, label %for.end, label %for.body
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| 
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| for.end:                                          ; preds = %for.body
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|   ret void
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| }
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