xref: /llvm-project/llvm/test/Transforms/IndVarSimplify/pr60944.ll (revision 660403940ca33d84c20b1cae343655f3d7872ada)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
2; RUN: opt -S -passes=indvars < %s | FileCheck %s
3
4@x = global i32 0
5
6; %loop2 is never entered and we cannot derive any fact about %iv from it.
7define i32 @main(i32 %iv.start, i32 %arg2) mustprogress {
8; CHECK-LABEL: define i32 @main
9; CHECK-SAME: (i32 [[IV_START:%.*]], i32 [[ARG2:%.*]]) #[[ATTR0:[0-9]+]] {
10; CHECK-NEXT:  entry:
11; CHECK-NEXT:    br label [[LOOP:%.*]]
12; CHECK:       loop:
13; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ], [ [[IV_START]], [[ENTRY:%.*]] ]
14; CHECK-NEXT:    br i1 false, label [[LOOP2_PREHEADER:%.*]], label [[LOOP_LATCH]]
15; CHECK:       loop2.preheader:
16; CHECK-NEXT:    br label [[LOOP2:%.*]]
17; CHECK:       loop2:
18; CHECK-NEXT:    br i1 true, label [[LOOP2_EXIT:%.*]], label [[LOOP2]]
19; CHECK:       loop2.exit:
20; CHECK-NEXT:    br label [[LOOP_LATCH]]
21; CHECK:       loop.latch:
22; CHECK-NEXT:    [[IV_NEXT]] = sdiv i32 [[ARG2]], [[IV]]
23; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i32 [[IV]], -1
24; CHECK-NEXT:    br i1 [[CMP2]], label [[LOOP_EXIT:%.*]], label [[LOOP]]
25; CHECK:       loop.exit:
26; CHECK-NEXT:    [[IV_NEXT_LCSSA:%.*]] = phi i32 [ [[IV_NEXT]], [[LOOP_LATCH]] ]
27; CHECK-NEXT:    ret i32 [[IV_NEXT_LCSSA]]
28;
29entry:
30  br label %loop
31
32loop:
33  %iv = phi i32 [ %iv.next, %loop.latch ], [ %iv.start, %entry ]
34  br i1 false, label %loop2.preheader, label %loop.latch
35
36loop2.preheader:
37  br label %loop2
38
39loop2:
40  %x = load i32, ptr @x, align 4
41  %cmp1 = icmp ult i32 %iv, %x
42  br i1 %cmp1, label %loop2.exit, label %loop2
43
44loop2.exit:
45  br label %loop.latch
46
47loop.latch:
48  %iv.next = sdiv i32 %arg2, %iv
49  %cmp2 = icmp eq i32 %iv, -1
50  br i1 %cmp2, label %loop.exit, label %loop
51
52loop.exit:
53  %iv.next.lcssa = phi i32 [ %iv.next, %loop.latch ]
54  ret i32 %iv.next.lcssa
55}
56