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; RUN: opt -passes='require<aa>,require<scalar-evolution>,require<aa>,loop(print-access-info)' -aa-pipeline='basic-aa' -disable-output < %s 2>&1 | FileCheck %s
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.10.0"
; TODO: Loop iteration counts are only required if we generate memory
; runtime checks. Missing iteration counts should not prevent
; analysis, if no runtime checks are required.
; No memory checks are required, because base pointers do not alias and we have
; a forward dependence for %a.
define void @safe_forward_dependence(i16* noalias %a,
i16* noalias %b) {
; CHECK-LABEL: safe_forward_dependence
; CHECK: for.body:
; CHECK-NEXT: Report: could not determine number of loop iterations
;
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%iv = phi i64 [ 0, %entry ], [ %iv.next, %for.body ]
%iv.next = add nuw nsw i64 %iv, 1
%arrayidxA_plus_2 = getelementptr inbounds i16, i16* %a, i64 %iv.next
%loadA_plus_2 = load i16, i16* %arrayidxA_plus_2, align 2
%arrayidxB = getelementptr inbounds i16, i16* %b, i64 %iv
%loadB = load i16, i16* %arrayidxB, align 2
%mul = mul i16 %loadB, %loadA_plus_2
%arrayidxA = getelementptr inbounds i16, i16* %a, i64 %iv
store i16 %mul, i16* %arrayidxA, align 2
%exitcond = icmp eq i16 %loadB, 20
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}
define void @unsafe_backwards_dependence(i16* noalias %a,
i16* noalias %b) {
; CHECK-LABEL: unsafe_backwards_dependence
; CHECK: for.body:
; CHECK-NEXT: Report: could not determine number of loop iterations
;
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%iv = phi i64 [ 1, %entry ], [ %iv.next, %for.body ]
%idx = add nuw nsw i64 %iv, -1
%iv.next = add nuw nsw i64 %iv, 1
%arrayidxA_plus_2 = getelementptr inbounds i16, i16* %a, i64 %idx
%loadA_plus_2 = load i16, i16* %arrayidxA_plus_2, align 2
%arrayidxB = getelementptr inbounds i16, i16* %b, i64 %iv
%loadB = load i16, i16* %arrayidxB, align 2
%mul = mul i16 %loadB, %loadA_plus_2
%arrayidxA = getelementptr inbounds i16, i16* %a, i64 %iv
store i16 %mul, i16* %arrayidxA, align 2
%exitcond = icmp eq i16 %loadB, 20
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}
define void @ptr_may_alias(i16* %a, i16* %b) {
; CHECK-LABEL: ptr_may_alias
; CHECK: for.body:
; CHECK-NEXT: Report: could not determine number of loop iterations
;
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%iv = phi i64 [ 1, %entry ], [ %iv.next, %for.body ]
%idx = add nuw nsw i64 %iv, -1
%iv.next = add nuw nsw i64 %iv, 1
%arrayidxA = getelementptr inbounds i16, i16* %a, i64 %iv
%loadA = load i16, i16* %arrayidxA, align 2
%arrayidxB = getelementptr inbounds i16, i16* %b, i64 %iv
%loadB = load i16, i16* %arrayidxB, align 2
%mul = mul i16 %loadB, %loadA
store i16 %mul, i16* %arrayidxA, align 2
%exitcond = icmp eq i16 %loadB, 20
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}
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