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1; RUN: opt -S -loop-load-elim < %s | FileCheck %s
2
3; We can't hoist conditional loads to the preheader for the initial value.
4; E.g. in the loop below we'd access array[-1] if we did:
5;
6;   for(int i = 0 ; i < n ; i++ )
7;     array[i] = ( i > 0 ? array[i - 1] : 0 ) + 4;
8
9target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
10target triple = "x86_64-apple-macosx10.11.0"
11
12define void @f(i32* %array, i32 %n) {
13entry:
14  %cmp10 = icmp sgt i32 %n, 0
15  br i1 %cmp10, label %for.body, label %for.cond.cleanup
16
17for.cond.cleanup:                                 ; preds = %cond.end, %entry
18  ret void
19
20for.body:                                         ; preds = %entry, %cond.end
21  %indvars.iv = phi i64 [ %indvars.iv.next, %cond.end ], [ 0, %entry ]
22; CHECK-NOT: %store_forwarded = phi
23  %cmp1 = icmp sgt i64 %indvars.iv, 0
24  br i1 %cmp1, label %cond.true, label %cond.end
25
26cond.true:                                        ; preds = %for.body
27  %0 = add nsw i64 %indvars.iv, -1
28  %arrayidx = getelementptr inbounds i32, i32* %array, i64 %0
29  %1 = load i32, i32* %arrayidx, align 4
30  br label %cond.end
31
32cond.end:                                         ; preds = %for.body, %cond.true
33  %cond = phi i32 [ %1, %cond.true ], [ 0, %for.body ]
34; CHECK: %cond = phi i32 [ %1, %cond.true ], [ 0, %for.body ]
35  %add = add nsw i32 %cond, 4
36  %arrayidx3 = getelementptr inbounds i32, i32* %array, i64 %indvars.iv
37  store i32 %add, i32* %arrayidx3, align 4
38  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
39  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
40  %exitcond = icmp eq i32 %lftr.wideiv, %n
41  br i1 %exitcond, label %for.cond.cleanup, label %for.body
42}
43