xref: /llvm-project/llvm/test/Transforms/LoopVersioning/single-iteration.ll (revision 7eea55fd4bf197fea20b7c255febf287664dce36)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
2; RUN: opt -passes=loop-versioning -S %s | FileCheck %s
3
4; Callers should not call LoopVersioning on single-iteration loops, as it
5; is very likely not profitable.
6; LoopVersioning faithfully versions single-iteration loops when the stride
7; is unknown.
8
9define double @single_iteration_unknown_stride(i32 %x, ptr %y, i1 %cond) {
10; CHECK-LABEL: define double @single_iteration_unknown_stride(
11; CHECK-SAME: i32 [[X:%.*]], ptr [[Y:%.*]], i1 [[COND:%.*]]) {
12; CHECK-NEXT:  [[ENTRY:.*:]]
13; CHECK-NEXT:    br i1 [[COND]], label %[[NOLOOP_EXIT:.*]], label %[[LOOP_BODY_LVER_CHECK:.*]]
14; CHECK:       [[LOOP_BODY_LVER_CHECK]]:
15; CHECK-NEXT:    [[SEXT7:%.*]] = sext i32 [[X]] to i64
16; CHECK-NEXT:    [[GEP8:%.*]] = getelementptr i8, ptr [[Y]], i64 8
17; CHECK-NEXT:    [[IDENT_CHECK:%.*]] = icmp ne i32 [[X]], 1
18; CHECK-NEXT:    br i1 [[IDENT_CHECK]], label %[[LOOP_BODY_PH_LVER_ORIG:.*]], label %[[LOOP_BODY_PH:.*]]
19; CHECK:       [[LOOP_BODY_PH_LVER_ORIG]]:
20; CHECK-NEXT:    br label %[[LOOP_BODY_LVER_ORIG:.*]]
21; CHECK:       [[LOOP_BODY_LVER_ORIG]]:
22; CHECK-NEXT:    [[PHI_LVER_ORIG:%.*]] = phi i64 [ 0, %[[LOOP_BODY_PH_LVER_ORIG]] ], [ [[ADD_LVER_ORIG:%.*]], %[[LOOP_BODY_LVER_ORIG]] ]
23; CHECK-NEXT:    [[MUL_LVER_ORIG:%.*]] = mul i64 [[PHI_LVER_ORIG]], [[SEXT7]]
24; CHECK-NEXT:    [[GEP10_LVER_ORIG:%.*]] = getelementptr double, ptr [[GEP8]], i64 [[MUL_LVER_ORIG]]
25; CHECK-NEXT:    [[LOAD11_LVER_ORIG:%.*]] = load double, ptr [[GEP10_LVER_ORIG]], align 8
26; CHECK-NEXT:    store double [[LOAD11_LVER_ORIG]], ptr [[Y]], align 8
27; CHECK-NEXT:    [[ADD_LVER_ORIG]] = add i64 [[PHI_LVER_ORIG]], 1
28; CHECK-NEXT:    [[ICMP_LVER_ORIG:%.*]] = icmp eq i64 [[PHI_LVER_ORIG]], 0
29; CHECK-NEXT:    br i1 [[ICMP_LVER_ORIG]], label %[[LOOP_EXIT_LOOPEXIT:.*]], label %[[LOOP_BODY_LVER_ORIG]]
30; CHECK:       [[LOOP_BODY_PH]]:
31; CHECK-NEXT:    br label %[[LOOP_BODY:.*]]
32; CHECK:       [[LOOP_BODY]]:
33; CHECK-NEXT:    [[PHI:%.*]] = phi i64 [ 0, %[[LOOP_BODY_PH]] ], [ [[ADD:%.*]], %[[LOOP_BODY]] ]
34; CHECK-NEXT:    [[MUL:%.*]] = mul i64 [[PHI]], [[SEXT7]]
35; CHECK-NEXT:    [[GEP10:%.*]] = getelementptr double, ptr [[GEP8]], i64 [[MUL]]
36; CHECK-NEXT:    [[LOAD11:%.*]] = load double, ptr [[GEP10]], align 8
37; CHECK-NEXT:    store double [[LOAD11]], ptr [[Y]], align 8
38; CHECK-NEXT:    [[ADD]] = add i64 [[PHI]], 1
39; CHECK-NEXT:    [[ICMP:%.*]] = icmp eq i64 [[PHI]], 0
40; CHECK-NEXT:    br i1 [[ICMP]], label %[[LOOP_EXIT_LOOPEXIT1:.*]], label %[[LOOP_BODY]]
41; CHECK:       [[NOLOOP_EXIT]]:
42; CHECK-NEXT:    [[SEXT:%.*]] = sext i32 [[X]] to i64
43; CHECK-NEXT:    [[GEP:%.*]] = getelementptr double, ptr [[Y]], i64 [[SEXT]]
44; CHECK-NEXT:    [[LOAD5:%.*]] = load double, ptr [[GEP]], align 8
45; CHECK-NEXT:    ret double [[LOAD5]]
46; CHECK:       [[LOOP_EXIT_LOOPEXIT]]:
47; CHECK-NEXT:    br label %[[LOOP_EXIT:.*]]
48; CHECK:       [[LOOP_EXIT_LOOPEXIT1]]:
49; CHECK-NEXT:    br label %[[LOOP_EXIT]]
50; CHECK:       [[LOOP_EXIT]]:
51; CHECK-NEXT:    [[SEXT2:%.*]] = sext i32 [[X]] to i64
52; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr double, ptr [[Y]], i64 [[SEXT2]]
53; CHECK-NEXT:    [[LOAD6:%.*]] = load double, ptr [[GEP2]], align 8
54; CHECK-NEXT:    ret double [[LOAD6]]
55;
56entry:
57  br i1 %cond, label %noloop.exit, label %loop.ph
58
59loop.ph:                                          ; preds = %entry
60  %sext7 = sext i32 %x to i64
61  %gep8 = getelementptr i8, ptr %y, i64 8
62  br label %loop.body
63
64loop.body:                                        ; preds = %loop.body, %loop.ph
65  %iv = phi i64 [ 0, %loop.ph ], [ %iv.next, %loop.body ]
66  %mul = mul i64 %iv, %sext7
67  %gep10 = getelementptr double, ptr %gep8, i64 %mul
68  %load11 = load double, ptr %gep10, align 8
69  store double %load11, ptr %y, align 8
70  %iv.next = add i64 %iv, 1
71  %icmp = icmp eq i64 %iv, 0
72  br i1 %icmp, label %loop.exit, label %loop.body
73
74noloop.exit:                                      ; preds = %entry
75  %sext = sext i32 %x to i64
76  %gep = getelementptr double, ptr %y, i64 %sext
77  %load5 = load double, ptr %gep, align 8
78  ret double %load5
79
80loop.exit:                                        ; preds = %loop.body
81  %sext2 = sext i32 %x to i64
82  %gep2 = getelementptr double, ptr %y, i64 %sext2
83  %load6 = load double, ptr %gep2, align 8
84  ret double %load6
85}
86