llvm-project/llvm/test/Analysis/LoopAccessAnalysis/pointer-with-unknown-bounds.ll

81 lines
2.7 KiB
LLVM

; RUN: opt -loop-accesses -analyze -enable-new-pm=0 < %s | FileCheck %s
; RUN: opt -aa-pipeline=basic-aa -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-LABEL: addrec_squared
; CHECK-NEXT: for.body:
; CHECK-NEXT: Report: unsafe dependent memory operations in loop
; CHECK-NOT: Report: cannot identify array bounds
; CHECK-NEXT: Dependences:
; CHECK-NEXT: Unknown:
; CHECK-NEXT: %loadA = load i16, i16* %arrayidxA, align 2 ->
; CHECK-NEXT: store i16 %mul, i16* %arrayidxA, align 2
define void @addrec_squared(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
}
; TODO: We cannot compute the bound for %arrayidxA_ub, because the index is
; loaded on each iteration. As %a and %b are no-alias, no memchecks are required
; and unknown bounds should not prevent further analysis.
define void @loaded_bound(i16* noalias %a, i16* noalias %b) {
; CHECK-LABEL: loaded_bound
; CHECK-NEXT: for.body:
; CHECK-NEXT: Report: cannot identify array bounds
; CHECK-NEXT: Dependences:
; CHECK-NEXT: Run-time memory checks:
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
%arrayidxB = getelementptr inbounds i16, i16* %b, i64 %iv
%loadB = load i16, i16* %arrayidxB, align 2
%arrayidxA_ub = getelementptr inbounds i16, i16* %a, i16 %loadB
%loadA_ub = load i16, i16* %arrayidxA_ub, align 2
%mul = mul i16 %loadB, %loadA_ub
%arrayidxA = getelementptr inbounds i16, i16* %a, i64 %iv
store i16 %mul, i16* %arrayidxA, align 2
%exitcond = icmp eq i64 %iv, 20
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}