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; RUN: opt -loop-accesses -analyze < %s | FileCheck %s
; Analyze this loop:
; for (i = 0; i < n; i++)
; A[i + 1] = A[i] * B[i] * C[i];
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.10.0"
; CHECK: Report: unsafe dependent memory operations in loop
; CHECK-NEXT: Interesting Dependences:
; CHECK-NEXT: Backward:
; CHECK-NEXT: %loadA = load i16, i16* %arrayidxA, align 2 ->
; CHECK-NEXT: store i16 %mul1, i16* %arrayidxA_plus_2, align 2
; CHECK: Run-time memory checks:
; CHECK-NEXT: 0:
; CHECK-NEXT: %arrayidxA_plus_2 = getelementptr inbounds i16, i16* %a, i64 %add
; CHECK-NEXT: %arrayidxB = getelementptr inbounds i16, i16* %b, i64 %storemerge3
; CHECK-NEXT: 1:
; CHECK-NEXT: %arrayidxA_plus_2 = getelementptr inbounds i16, i16* %a, i64 %add
; CHECK-NEXT: %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %storemerge3
@n = global i32 20, align 4
@B = common global i16* null, align 8
@A = common global i16* null, align 8
@C = common global i16* null, align 8
define void @f() {
entry:
%a = load i16*, i16** @A, align 8
%b = load i16*, i16** @B, align 8
%c = load i16*, i16** @C, align 8
br label %for.body
for.body: ; preds = %for.body, %entry
%storemerge3 = phi i64 [ 0, %entry ], [ %add, %for.body ]
%arrayidxA = getelementptr inbounds i16, i16* %a, i64 %storemerge3
%loadA = load i16, i16* %arrayidxA, align 2
%arrayidxB = getelementptr inbounds i16, i16* %b, i64 %storemerge3
%loadB = load i16, i16* %arrayidxB, align 2
%arrayidxC = getelementptr inbounds i16, i16* %c, i64 %storemerge3
%loadC = load i16, i16* %arrayidxC, align 2
%mul = mul i16 %loadB, %loadA
%mul1 = mul i16 %mul, %loadC
%add = add nuw nsw i64 %storemerge3, 1
%arrayidxA_plus_2 = getelementptr inbounds i16, i16* %a, i64 %add
store i16 %mul1, i16* %arrayidxA_plus_2, align 2
%exitcond = icmp eq i64 %add, 20
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}
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