1; RUN: llc < %s -mtriple=x86_64-apple-macosx -disable-lsr -post-RA-scheduler=1 -break-anti-dependencies=critical  | FileCheck %s
2
3; In PR20020, the critical anti-dependency breaker algorithm mistakenly
4; changes the register operands of an 'xorl %eax, %eax' to 'xorl %ecx, %ecx'
5; and then immediately reloads %rcx with a value based on the wrong %rax
6
7; CHECK-NOT: xorl %ecx, %ecx
8; CHECK: leaq 1(%rax), %rcx
9
10
11%struct.planet = type { double, double, double }
12
13; Function Attrs: nounwind ssp uwtable
14define void @advance(i32 %nbodies, %struct.planet* nocapture %bodies) #0 {
15entry:
16  %cmp4 = icmp sgt i32 %nbodies, 0
17  br i1 %cmp4, label %for.body.preheader, label %for.end38
18
19for.body.preheader:                               ; preds = %entry
20  %gep = getelementptr %struct.planet, %struct.planet* %bodies, i64 1, i32 1
21  %gep13 = bitcast double* %gep to %struct.planet*
22  %0 = add i32 %nbodies, -1
23  br label %for.body
24
25for.body:                                         ; preds = %for.body.preheader, %for.inc20
26  %iv19 = phi i32 [ %0, %for.body.preheader ], [ %iv.next, %for.inc20 ]
27  %iv = phi %struct.planet* [ %gep13, %for.body.preheader ], [ %gep14, %for.inc20 ]
28  %iv9 = phi i64 [ %iv.next10, %for.inc20 ], [ 0, %for.body.preheader ]
29  %iv.next10 = add nuw nsw i64 %iv9, 1
30  %1 = trunc i64 %iv.next10 to i32
31  %cmp22 = icmp slt i32 %1, %nbodies
32  br i1 %cmp22, label %for.body3.lr.ph, label %for.inc20
33
34for.body3.lr.ph:                                  ; preds = %for.body
35  %x = getelementptr inbounds %struct.planet, %struct.planet* %bodies, i64 %iv9, i32 0
36  %y = getelementptr inbounds %struct.planet, %struct.planet* %bodies, i64 %iv9, i32 1
37  %vx = getelementptr inbounds %struct.planet, %struct.planet* %bodies, i64 %iv9, i32 2
38  br label %for.body3
39
40for.body3:                                        ; preds = %for.body3, %for.body3.lr.ph
41  %iv20 = phi i32 [ %iv.next21, %for.body3 ], [ %iv19, %for.body3.lr.ph ]
42  %iv15 = phi %struct.planet* [ %gep16, %for.body3 ], [ %iv, %for.body3.lr.ph ]
43  %iv1517 = bitcast %struct.planet* %iv15 to double*
44  %2 = load double, double* %x, align 8
45  %gep18 = getelementptr double, double* %iv1517, i64 -1
46  %3 = load double, double* %gep18, align 8
47  %sub = fsub double %2, %3
48  %4 = load double, double* %y, align 8
49  %5 = load double, double* %iv1517, align 8
50  %sub8 = fsub double %4, %5
51  %add10 = fadd double %sub, %sub8
52  %call = tail call double @sqrt(double %sub8) #2
53  store double %add10, double* %vx, align 8
54  %gep16 = getelementptr %struct.planet, %struct.planet* %iv15, i64 1
55  %iv.next21 = add i32 %iv20, -1
56  %exitcond = icmp eq i32 %iv.next21, 0
57  br i1 %exitcond, label %for.inc20, label %for.body3
58
59for.inc20:                                        ; preds = %for.body3, %for.body
60  %lftr.wideiv11 = trunc i64 %iv.next10 to i32
61  %gep14 = getelementptr %struct.planet, %struct.planet* %iv, i64 1
62  %iv.next = add i32 %iv19, -1
63  %exitcond12 = icmp eq i32 %lftr.wideiv11, %nbodies
64  br i1 %exitcond12, label %for.end38, label %for.body
65
66for.end38:                                        ; preds = %for.inc20, %entry
67  ret void
68}
69
70; Function Attrs: nounwind
71declare double @sqrt(double) #1
72
73attributes #0 = { "no-frame-pointer-elim-non-leaf" }
74