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; RUN: opt -loop-load-elim -S < %s | FileCheck %s
; Simple st->ld forwarding derived from a lexical forwrad dep.
;
; for (unsigned i = 0; i < 100; i++) {
; A[i+1] = B[i] + 2;
; C[i] = A[i] * 2;
; }
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
define void @f(i32* %A, i32* %B, i32* %C, i64 %N) {
; CHECK: for.body.lver.check:
; CHECK: %found.conflict{{.*}} =
; CHECK-NOT: %found.conflict{{.*}} =
entry:
; for.body.ph:
; CHECK: %load_initial = load i32, i32* %A
br label %for.body
for.body: ; preds = %for.body, %entry
; CHECK: %store_forwarded = phi i32 [ %load_initial, %for.body.ph ], [ %a_p1, %for.body ]
%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%Aidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next
%Bidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
%Cidx = getelementptr inbounds i32, i32* %C, i64 %indvars.iv
%Aidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
%b = load i32, i32* %Bidx, align 4
%a_p1 = add i32 %b, 2
store i32 %a_p1, i32* %Aidx_next, align 4
%a = load i32, i32* %Aidx, align 4
; CHECK: %c = mul i32 %store_forwarded, 2
%c = mul i32 %a, 2
store i32 %c, i32* %Cidx, 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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