1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -S -loop-unroll -unroll-runtime -unroll-runtime-multi-exit < %s | FileCheck %s
3
4; This loop has a known trip count on the non-latch exit. When performing
5; runtime unrolling (at least when using a prologue rather than epilogue) we
6; should not fold that exit based on known trip count information prior to
7; prologue insertion, as that may change the trip count for the modified loop.
8
9define void @test(i32 %s, i32 %n) {
10; CHECK-LABEL: @test(
11; CHECK-NEXT:  entry:
12; CHECK-NEXT:    [[N2:%.*]] = add i32 [[S:%.*]], 123
13; CHECK-NEXT:    br label [[LOOP:%.*]]
14; CHECK:       loop:
15; CHECK-NEXT:    [[I:%.*]] = phi i32 [ [[S]], [[ENTRY:%.*]] ], [ [[I_INC:%.*]], [[LATCH:%.*]] ]
16; CHECK-NEXT:    [[C1:%.*]] = icmp eq i32 [[I]], [[N2]]
17; CHECK-NEXT:    br i1 [[C1]], label [[EXIT1:%.*]], label [[LATCH]]
18; CHECK:       latch:
19; CHECK-NEXT:    [[C2:%.*]] = icmp eq i32 [[I]], [[N:%.*]]
20; CHECK-NEXT:    [[I_INC]] = add i32 [[I]], 1
21; CHECK-NEXT:    br i1 [[C2]], label [[EXIT2:%.*]], label [[LOOP]]
22; CHECK:       exit1:
23; CHECK-NEXT:    ret void
24; CHECK:       exit2:
25; CHECK-NEXT:    ret void
26;
27entry:
28  %n2 = add i32 %s, 123
29  br label %loop
30
31loop:
32  %i = phi i32 [ %s, %entry], [ %i.inc, %latch ]
33  %c1 = icmp eq i32 %i, %n2
34  br i1 %c1, label %exit1, label %latch
35
36latch:
37  %c2 = icmp eq i32 %i, %n
38  %i.inc = add i32 %i, 1
39  br i1 %c2, label %exit2, label %loop
40
41exit1:
42  ret void
43
44exit2:
45  ret void
46}
47