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1; RUN: opt -passes='print<access-info>' -aa-pipeline='basic-aa' -disable-output < %s 2>&1 | FileCheck %s2 3; For this loop:4; for (int i = 0; i < n; i++)5; A[2 * i] = A[2 * i] + B[i];6;7; , SCEV is unable to prove that A[2 * i] does not overflow. However,8; analyzing the IR helps us to conclude it and in turn allow dependence9; analysis.10 11target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"12 13; CHECK: Memory dependences are safe{{$}}14 15define void @f(ptr noalias %a,16 ptr noalias %b, i64 %N) {17entry:18 br label %for.body19 20for.body: ; preds = %for.body, %entry21 %ind = phi i64 [ 0, %entry ], [ %inc, %for.body ]22 23 %mul = mul nuw nsw i64 %ind, 224 25 %arrayidxA = getelementptr inbounds i16, ptr %a, i64 %mul26 %loadA = load i16, ptr %arrayidxA, align 227 28 %arrayidxB = getelementptr inbounds i16, ptr %b, i64 %ind29 %loadB = load i16, ptr %arrayidxB, align 230 31 %add = mul i16 %loadA, %loadB32 33 store i16 %add, ptr %arrayidxA, align 234 35 %inc = add nuw nsw i64 %ind, 136 %exitcond = icmp eq i64 %inc, %N37 br i1 %exitcond, label %for.end, label %for.body38 39for.end: ; preds = %for.body40 ret void41}42