1; RUN: opt -loop-load-elim -S < %s | FileCheck %s
2; RUN: opt -passes=loop-load-elim -S < %s | FileCheck %s
3
4; Simple st->ld forwarding derived from a lexical backward dep.
5;
6;   for (unsigned i = 0; i < 100; i++)
7;     A[i+1] = A[i] + B[i];
8
9target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
10
11define void @f(i32* noalias nocapture %A, i32* noalias nocapture readonly %B, i64 %N) {
12entry:
13; CHECK: %load_initial = load i32, i32* %A
14  br label %for.body
15
16for.body:                                         ; preds = %for.body, %entry
17; CHECK: %store_forwarded = phi i32 [ %load_initial, %entry ], [ %add, %for.body ]
18  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
19  %arrayidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
20  %load = load i32, i32* %arrayidx, align 4
21  %arrayidx2 = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
22  %load_1 = load i32, i32* %arrayidx2, align 4
23; CHECK: %add = add i32 %load_1, %store_forwarded
24  %add = add i32 %load_1, %load
25  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
26  %arrayidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next
27  store i32 %add, i32* %arrayidx_next, align 4
28  %exitcond = icmp eq i64 %indvars.iv.next, %N
29  br i1 %exitcond, label %for.end, label %for.body
30
31for.end:                                          ; preds = %for.body
32  ret void
33}
34