pointer-with-unknown-bounds.ll
1.4 KB
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; RUN: opt -loop-accesses -analyze < %s | FileCheck %s
; RUN: opt -passes='require<scalar-evolution>,require<aa>,loop(print-access-info)' -disable-output < %s 2>&1 | FileCheck %s
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
; We shouldn't quit the analysis if we encounter a pointer without known
; bounds *unless* we actually need to emit a memcheck for it. (We only
; compute bounds for SCEVAddRecs so A[i*i] is deemed not having known bounds.)
;
; for (i = 0; i < 20; ++i)
; A[i*i] *= 2;
; CHECK: for.body:
; CHECK: Report: unsafe dependent memory operations in loop
; CHECK-NOT: Report: cannot identify array bounds
; CHECK: Dependences:
; CHECK: Unknown:
; CHECK: %loadA = load i16, i16* %arrayidxA, align 2 ->
; CHECK: store i16 %mul, i16* %arrayidxA, align 2
define void @f(i16* %a) {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%ind = phi i64 [ 0, %entry ], [ %add, %for.body ]
%access_ind = mul i64 %ind, %ind
%arrayidxA = getelementptr inbounds i16, i16* %a, i64 %access_ind
%loadA = load i16, i16* %arrayidxA, align 2
%mul = mul i16 %loadA, 2
store i16 %mul, i16* %arrayidxA, align 2
%add = add nuw nsw i64 %ind, 1
%exitcond = icmp eq i64 %add, 20
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}