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; RUN: opt -passes=loop-load-elim -S < %s | FileCheck %s
; No loop-carried forwarding: The intervening store to A[i] kills the stored
; value from the previous iteration.
;
; for (unsigned i = 0; i < 100; i++) {
; A[i] = 1;
; A[i+1] = A[i] + B[i];
; }
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
define void @f(ptr noalias nocapture %A, ptr noalias nocapture readonly %B, i64 %N) {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
; CHECK-NOT: %store_forwarded
%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
%arrayidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
store i32 1, ptr %arrayidx, align 4
%a = load i32, ptr %arrayidx, align 4
%arrayidxB = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
%b = load i32, ptr %arrayidxB, align 4
; CHECK: %add = add i32 %b, %a
%add = add i32 %b, %a
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%arrayidx_next = getelementptr inbounds i32, ptr %A, i64 %indvars.iv.next
store i32 %add, ptr %arrayidx_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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