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