1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -indvars -replexitval=always -S | FileCheck %s
3; Make sure IndVars preserves LCSSA form, especially across loop nests.
4
5target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
6
7define void @PR18642(i32 %x) {
8; CHECK-LABEL: @PR18642(
9; CHECK-NEXT:  entry:
10; CHECK-NEXT:    br label [[OUTER_HEADER:%.*]]
11; CHECK:       outer.header:
12; CHECK-NEXT:    br label [[INNER_HEADER:%.*]]
13; CHECK:       inner.header:
14; CHECK-NEXT:    br i1 false, label [[INNER_LATCH:%.*]], label [[OUTER_LATCH:%.*]]
15; CHECK:       inner.latch:
16; CHECK-NEXT:    br i1 true, label [[INNER_HEADER]], label [[EXIT_LOOPEXIT:%.*]]
17; CHECK:       outer.latch:
18; CHECK-NEXT:    br i1 false, label [[OUTER_HEADER]], label [[EXIT_LOOPEXIT1:%.*]]
19; CHECK:       exit.loopexit:
20; CHECK-NEXT:    [[INC_LCSSA:%.*]] = phi i32 [ -2147483648, [[INNER_LATCH]] ]
21; CHECK-NEXT:    br label [[EXIT:%.*]]
22; CHECK:       exit.loopexit1:
23; CHECK-NEXT:    br label [[EXIT]]
24; CHECK:       exit:
25; CHECK-NEXT:    [[EXIT_PHI:%.*]] = phi i32 [ [[INC_LCSSA]], [[EXIT_LOOPEXIT]] ], [ undef, [[EXIT_LOOPEXIT1]] ]
26; CHECK-NEXT:    ret void
27;
28entry:
29  br label %outer.header
30
31outer.header:
32  %outer.iv = phi i32 [ 0, %entry ], [ %x, %outer.latch ]
33  br label %inner.header
34
35inner.header:
36  %inner.iv = phi i32 [ undef, %outer.header ], [ %inc, %inner.latch ]
37  %cmp1 = icmp slt i32 %inner.iv, %outer.iv
38  br i1 %cmp1, label %inner.latch, label %outer.latch
39
40inner.latch:
41  %inc = add nsw i32 %inner.iv, 1
42  %cmp2 = icmp slt i32 %inner.iv, %outer.iv
43  br i1 %cmp2, label %inner.header, label %exit
44
45outer.latch:
46  br i1 undef, label %outer.header, label %exit
47
48
49
50exit:
51  %exit.phi = phi i32 [ %inc, %inner.latch ], [ undef, %outer.latch ]
52  ret void
53}
54