xref: /llvm-project/llvm/test/Transforms/LoopVectorize/ARM/tail-folding-loop-hint.ll (revision 82821254f532c1dbdfd5d985ef7130511efaaa83)
1; RUN: opt -mtriple=thumbv8.1m.main-arm-eabihf -mattr=+mve.fp -passes=loop-vectorize -tail-predication=enabled -S < %s | \
2; RUN:  FileCheck %s
3
4target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
5
6; Check that loop hint predicate.enable loop can overrule the TTI hook. For
7; this test case, the TTI hook rejects tail-predication:
8;
9;   ARMHWLoops: Trip count does not fit into 32bits
10;   preferPredicateOverEpilogue: hardware-loop is not profitable.
11;
12define dso_local void @tail_folding(ptr noalias nocapture %A, ptr noalias nocapture readonly %B, ptr noalias nocapture readonly %C) {
13; CHECK-LABEL: tail_folding(
14; CHECK:       vector.body:
15; CHECK-NOT:   call <4 x i32> @llvm.masked.load.v4i32.p0(
16; CHECK-NOT:   call void @llvm.masked.store.v4i32.p0(
17; CHECK:       br i1 %{{.*}}, label %{{.*}}, label %vector.body, !llvm.loop [[VEC_LOOP1:![0-9]+]]
18;
19; CHECK:       br i1 %{{.*}}, label %{{.*}}, label %for.body, !llvm.loop [[SCALAR_LOOP1:![0-9]+]]
20entry:
21  br label %for.body
22
23for.cond.cleanup:
24  ret void
25
26for.body:
27  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
28  %arrayidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
29  %0 = load i32, ptr %arrayidx, align 4
30  %arrayidx2 = getelementptr inbounds i32, ptr %C, i64 %indvars.iv
31  %1 = load i32, ptr %arrayidx2, align 4
32  %add = add nsw i32 %1, %0
33  %arrayidx4 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
34  store i32 %add, ptr %arrayidx4, align 4
35  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
36  %exitcond = icmp eq i64 %indvars.iv.next, 430
37  br i1 %exitcond, label %for.cond.cleanup, label %for.body
38}
39
40; The same test case but now with predicate.enable = true should get
41; tail-folded.
42;
43define dso_local void @predicate_loop_hint(ptr noalias nocapture %A, ptr noalias nocapture readonly %B, ptr noalias nocapture readonly %C) {
44; CHECK-LABEL: predicate_loop_hint(
45; CHECK:       vector.body:
46; CHECK:         %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
47; CHECK:         %[[ELEM0:.*]] = add i64 %index, 0
48; CHECK:         %active.lane.mask = call <4 x i1> @llvm.get.active.lane.mask.v4i1.i64(i64 %[[ELEM0]], i64 430)
49; CHECK:         %[[WML1:.*]] = call <4 x i32> @llvm.masked.load.v4i32.p0({{.*}}<4 x i1> %active.lane.mask
50; CHECK:         %[[WML2:.*]] = call <4 x i32> @llvm.masked.load.v4i32.p0({{.*}}<4 x i1> %active.lane.mask
51; CHECK:         %[[ADD:.*]] = add nsw <4 x i32> %[[WML2]], %[[WML1]]
52; CHECK:         call void @llvm.masked.store.v4i32.p0(<4 x i32> %[[ADD]], {{.*}}<4 x i1> %active.lane.mask
53; CHECK:         %index.next = add nuw i64 %index, 4
54; CHECK:         br i1 %{{.*}}, label %{{.*}}, label %vector.body, !llvm.loop [[VEC_LOOP2:![0-9]+]]
55;
56; CHECK:         br i1 %{{.*}}, label %{{.*}}, label %for.body, !llvm.loop [[SCALAR_LOOP2:![0-9]+]]
57entry:
58  br label %for.body
59
60for.cond.cleanup:
61  ret void
62
63for.body:
64  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
65  %arrayidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
66  %0 = load i32, ptr %arrayidx, align 4
67  %arrayidx2 = getelementptr inbounds i32, ptr %C, i64 %indvars.iv
68  %1 = load i32, ptr %arrayidx2, align 4
69  %add = add nsw i32 %1, %0
70  %arrayidx4 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
71  store i32 %add, ptr %arrayidx4, align 4
72  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
73  %exitcond = icmp eq i64 %indvars.iv.next, 430
74  br i1 %exitcond, label %for.cond.cleanup, label %for.body, !llvm.loop !6
75}
76
77; CHECK:      [[VEC_LOOP1]] = distinct !{[[VEC_LOOP1]], [[MD_IS_VEC:![0-9]+]], [[MD_RT_UNROLL_DIS:![0-9]+]]}
78; CHECK-NEXT: [[MD_IS_VEC:![0-9]+]] = !{!"llvm.loop.isvectorized", i32 1}
79; CHECK-NEXT: [[MD_RT_UNROLL_DIS]] = !{!"llvm.loop.unroll.runtime.disable"}
80; CHECK-NEXT: [[SCALAR_LOOP1]] = distinct !{[[SCALAR_LOOP1]], [[MD_RT_UNROLL_DIS]], [[MD_IS_VEC]]}
81; CHECK-NEXT: [[VEC_LOOP2]] = distinct !{[[VEC_LOOP2]], [[MD_IS_VEC]], [[MD_RT_UNROLL_DIS]]}
82; CHECK-NEXT: [[SCALAR_LOOP2]] = distinct !{[[SCALAR_LOOP2]], [[MD_RT_UNROLL_DIS]], [[MD_IS_VEC]]}
83
84!6 = distinct !{!6, !7, !8}
85!7 = !{!"llvm.loop.vectorize.predicate.enable", i1 true}
86!8 = !{!"llvm.loop.vectorize.enable", i1 true}
87