1 ; RUN: opt -basicaa -loop-accesses -analyze < %s | FileCheck %s 2 3 ; If the arrays don't alias this loop is safe with no memchecks: 4 ; for (i = 0; i < n; i++) 5 ; A[i] = A[i+1] * B[i] * C[i]; 6 7 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" 8 target triple = "x86_64-apple-macosx10.10.0" 9 10 ; Check the loop-carried forward anti-dep between the load of A[i+1] and the 11 ; store of A[i]; 12 13 ; CHECK: Memory dependences are safe{{$}} 14 ; CHECK-NEXT: Dependences: 15 ; CHECK-NEXT: Forward: 16 ; CHECK-NEXT: %loadA_plus_2 = load i16, i16* %arrayidxA_plus_2, align 2 -> 17 ; CHECK-NEXT: store i16 %mul1, i16* %arrayidxA, align 2 18 19 20 define void @f(i16* noalias %a, 21 i16* noalias %b, 22 i16* noalias %c) { 23 entry: 24 br label %for.body 25 26 for.body: ; preds = %for.body, %entry 27 %ind = phi i64 [ 0, %entry ], [ %add, %for.body ] 28 29 %add = add nuw nsw i64 %ind, 1 30 31 %arrayidxA_plus_2 = getelementptr inbounds i16, i16* %a, i64 %add 32 %loadA_plus_2 = load i16, i16* %arrayidxA_plus_2, align 2 33 34 %arrayidxB = getelementptr inbounds i16, i16* %b, i64 %ind 35 %loadB = load i16, i16* %arrayidxB, align 2 36 37 %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %ind 38 %loadC = load i16, i16* %arrayidxC, align 2 39 40 %mul = mul i16 %loadB, %loadA_plus_2 41 %mul1 = mul i16 %mul, %loadC 42 43 %arrayidxA = getelementptr inbounds i16, i16* %a, i64 %ind 44 store i16 %mul1, i16* %arrayidxA, align 2 45 46 %exitcond = icmp eq i64 %add, 20 47 br i1 %exitcond, label %for.end, label %for.body 48 49 for.end: ; preds = %for.body 50 ret void 51 } 52
