xref: /llvm-project/llvm/test/Transforms/LoopPredication/poison.ll (revision 99da317331e37d530610695b0cf44ba2686b735e)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -S -passes=loop-predication < %s 2>&1 | FileCheck %s
3; RUN: opt -S -passes='require<scalar-evolution>,loop-mssa(loop-predication)' -verify-memoryssa < %s 2>&1 | FileCheck %s
4
5declare void @llvm.experimental.guard(i1, ...)
6
7; Check the case when N on latch exit might be poison.
8define i32 @test1(i32 %length, i32 %nlimit) {
9; CHECK-LABEL: @test1(
10; CHECK-NEXT:  entry:
11; CHECK-NEXT:    [[M:%.*]] = add nuw nsw i32 [[NLIMIT:%.*]], 2
12; CHECK-NEXT:    [[N:%.*]] = xor i32 [[M]], 1
13; CHECK-NEXT:    [[TMP0:%.*]] = icmp ule i32 [[N]], [[LENGTH:%.*]]
14; CHECK-NEXT:    [[TMP1:%.*]] = icmp ult i32 0, [[LENGTH]]
15; CHECK-NEXT:    [[TMP2:%.*]] = and i1 [[TMP1]], [[TMP0]]
16; CHECK-NEXT:    [[TMP3:%.*]] = freeze i1 [[TMP2]]
17; CHECK-NEXT:    br label [[LOOP:%.*]]
18; CHECK:       loop:
19; CHECK-NEXT:    [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[OK:%.*]] ], [ 0, [[ENTRY:%.*]] ]
20; CHECK-NEXT:    [[J:%.*]] = phi i32 [ [[J_NEXT:%.*]], [[OK]] ], [ 0, [[ENTRY]] ]
21; CHECK-NEXT:    [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[J]], [[LENGTH]]
22; CHECK-NEXT:    call void (i1, ...) @llvm.experimental.guard(i1 [[TMP3]], i32 9) [ "deopt"() ]
23; CHECK-NEXT:    call void @llvm.assume(i1 [[WITHIN_BOUNDS]])
24; CHECK-NEXT:    [[TMP:%.*]] = icmp ult i32 [[NLIMIT]], 1000
25; CHECK-NEXT:    br i1 [[TMP]], label [[OK]], label [[EXIT:%.*]]
26; CHECK:       ok:
27; CHECK-NEXT:    [[I_NEXT]] = add i32 [[I]], 1
28; CHECK-NEXT:    [[J_NEXT]] = add i32 [[J]], 1
29; CHECK-NEXT:    [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]]
30; CHECK-NEXT:    br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT]]
31; CHECK:       exit:
32; CHECK-NEXT:    ret i32 0
33;
34entry:
35  ; %n might be a poison.
36  %m = add nuw nsw i32 %nlimit, 2
37  %n = xor i32 %m, 1
38  br label %loop
39
40loop:
41  %i = phi i32 [ %i.next, %ok ], [ 0, %entry ]
42  %j = phi i32 [ %j.next, %ok ], [ 0, %entry ]
43  %within.bounds = icmp ult i32 %j, %length
44  call void (i1, ...) @llvm.experimental.guard(i1 %within.bounds, i32 9) [ "deopt"() ]
45
46  ; This check guarantees %n is not a posion.
47  %tmp = icmp ult i32 %nlimit, 1000
48  br i1 %tmp, label %ok, label %exit
49
50ok:
51  %i.next = add i32 %i, 1
52  %j.next = add i32 %j, 1
53  %continue = icmp ult i32 %i.next, %n
54  br i1 %continue, label %loop, label %exit
55
56exit:
57  ret i32 0
58}
59
60
61; Check the case when start value of IV might be a poison.
62define i32 @test2(i32 noundef %length, i32 noundef %nlimit, i32 %istart) {
63; CHECK-LABEL: @test2(
64; CHECK-NEXT:  entry:
65; CHECK-NEXT:    [[M:%.*]] = add nuw nsw i32 [[ISTART:%.*]], 2
66; CHECK-NEXT:    [[ISTART2:%.*]] = xor i32 [[M]], 1
67; CHECK-NEXT:    [[TMP0:%.*]] = add i32 [[ISTART2]], [[LENGTH:%.*]]
68; CHECK-NEXT:    [[TMP1:%.*]] = add i32 [[TMP0]], -1
69; CHECK-NEXT:    [[TMP2:%.*]] = icmp ule i32 [[NLIMIT:%.*]], [[TMP1]]
70; CHECK-NEXT:    [[TMP3:%.*]] = icmp ult i32 1, [[LENGTH]]
71; CHECK-NEXT:    [[TMP4:%.*]] = and i1 [[TMP3]], [[TMP2]]
72; CHECK-NEXT:    [[TMP5:%.*]] = freeze i1 [[TMP4]]
73; CHECK-NEXT:    br label [[LOOP:%.*]]
74; CHECK:       loop:
75; CHECK-NEXT:    [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[OK:%.*]] ], [ [[ISTART2]], [[ENTRY:%.*]] ]
76; CHECK-NEXT:    [[J:%.*]] = phi i32 [ [[J_NEXT:%.*]], [[OK]] ], [ 1, [[ENTRY]] ]
77; CHECK-NEXT:    [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[J]], [[LENGTH]]
78; CHECK-NEXT:    call void (i1, ...) @llvm.experimental.guard(i1 [[TMP5]], i32 9) [ "deopt"() ]
79; CHECK-NEXT:    call void @llvm.assume(i1 [[WITHIN_BOUNDS]])
80; CHECK-NEXT:    [[TMP:%.*]] = icmp ult i32 [[ISTART]], 1000
81; CHECK-NEXT:    br i1 [[TMP]], label [[OK]], label [[EXIT:%.*]]
82; CHECK:       ok:
83; CHECK-NEXT:    [[I_NEXT]] = add i32 [[I]], 1
84; CHECK-NEXT:    [[J_NEXT]] = add i32 [[J]], 1
85; CHECK-NEXT:    [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[NLIMIT]]
86; CHECK-NEXT:    br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT]]
87; CHECK:       exit:
88; CHECK-NEXT:    ret i32 0
89;
90entry:
91  ; %m might be a poison.
92  %m = add nuw nsw i32 %istart, 2
93  %istart2 = xor i32 %m, 1
94  br label %loop
95
96loop:
97  %i = phi i32 [ %i.next, %ok ], [ %istart2, %entry ]
98  %j = phi i32 [ %j.next, %ok ], [ 1, %entry ]
99  %within.bounds = icmp ult i32 %j, %length
100  call void (i1, ...) @llvm.experimental.guard(i1 %within.bounds, i32 9) [ "deopt"() ]
101  ; This check guarantees %n is not a posion.
102  %tmp = icmp ult i32 %istart, 1000
103  br i1 %tmp, label %ok, label %exit
104
105ok:
106  %i.next = add i32 %i, 1
107  %j.next = add i32 %j, 1
108  %continue = icmp ult i32 %i.next, %nlimit
109  br i1 %continue, label %loop, label %exit
110
111exit:
112  ret i32 0
113}
114