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; RUN: opt -basicaa -loop-accesses -analyze < %s | FileCheck %s
; For this loop:
; for (int i = 0; i < n; i++)
; A[2 * i] = A[2 * i] + B[i];
;
; , SCEV is unable to prove that A[2 * i] does not overflow. However,
; analyzing the IR helps us to conclude it and in turn allow dependence
; analysis.
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
; CHECK: Memory dependences are safe{{$}}
define void @f(i16* noalias %a,
i16* noalias %b, i64 %N) {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%ind = phi i64 [ 0, %entry ], [ %inc, %for.body ]
%mul = mul nuw nsw i64 %ind, 2
%arrayidxA = getelementptr inbounds i16, i16* %a, i64 %mul
%loadA = load i16, i16* %arrayidxA, align 2
%arrayidxB = getelementptr inbounds i16, i16* %b, i64 %ind
%loadB = load i16, i16* %arrayidxB, align 2
%add = mul i16 %loadA, %loadB
store i16 %add, i16* %arrayidxA, align 2
%inc = add nuw nsw i64 %ind, 1
%exitcond = icmp eq i64 %inc, %N
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}
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