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; RUN: opt -basicaa -loop-load-elim -S < %s | FileCheck %s
; In this case the later store forward to the load:
;
; for (unsigned i = 0; i < 100; i++) {
; B[i] = A[i] + 1;
; A[i+1] = C[i] + 2;
; A[i+1] = D[i] + 3;
; }
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
define void @f(i32* noalias nocapture %A, i32* noalias nocapture readonly %B,
i32* noalias nocapture %C, i32* noalias nocapture readonly %D,
i64 %N) {
entry:
; CHECK: %load_initial = load i32, i32* %A
br label %for.body
for.body: ; preds = %for.body, %entry
; CHECK: %store_forwarded = phi i32 [ %load_initial, %entry ], [ %addD, %for.body ]
%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
%arrayidxA = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
%loadA = load i32, i32* %arrayidxA, align 4
; CHECK: %addA = add i32 %store_forwarded, 1
%addA = add i32 %loadA, 1
%arrayidxB = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
store i32 %addA, i32* %arrayidxB, align 4
%arrayidxC = getelementptr inbounds i32, i32* %C, i64 %indvars.iv
%loadC = load i32, i32* %arrayidxC, align 4
%addC = add i32 %loadC, 2
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%arrayidxA_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next
store i32 %addC, i32* %arrayidxA_next, align 4
%arrayidxD = getelementptr inbounds i32, i32* %D, i64 %indvars.iv
%loadD = load i32, i32* %arrayidxD, align 4
%addD = add i32 %loadD, 3
store i32 %addD, i32* %arrayidxA_next, align 4
%exitcond = icmp eq i64 %indvars.iv.next, %N
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
ret void
}
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