xref: /llvm-project/llvm/test/Transforms/LoopVectorize/ARM/tail-folding-scalar-epilogue-fallback.ll (revision 2fab927546b34f5af7770541a9bbb974d9818c5c)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -S -passes=loop-vectorize -mattr=+armv8.1-m.main,+mve.fp -tail-predication=disabled< %s | FileCheck %s
3; RUN: opt -S -passes=loop-vectorize -mattr=+armv8.1-m.main,+mve.fp -tail-predication=enabled < %s | FileCheck %s
4
5; This test should produce the same result (vectorized loop + scalar epilogue) with
6; default options and when MVE Tail Predication is enabled, as this loop's tail cannot be folded
7; by masking due to an outside user of %incdec.ptr in %end.
8
9target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
10target triple = "thumbv8.1m.main-arm-unknown-eabihf"
11
12define void @outside_user_blocks_tail_folding(ptr nocapture readonly %ptr, i32 %size, ptr %pos) {
13; CHECK-LABEL: @outside_user_blocks_tail_folding(
14; CHECK-NEXT:  header:
15; CHECK-NEXT:    [[PTR0:%.*]] = load ptr, ptr [[POS:%.*]], align 4
16; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i32 [[SIZE:%.*]], 16
17; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
18; CHECK:       vector.ph:
19; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i32 [[SIZE]], 16
20; CHECK-NEXT:    [[N_VEC:%.*]] = sub i32 [[SIZE]], [[N_MOD_VF]]
21; CHECK-NEXT:    [[IND_END:%.*]] = sub i32 [[SIZE]], [[N_VEC]]
22; CHECK-NEXT:    [[IND_END1:%.*]] = getelementptr i8, ptr [[PTR:%.*]], i32 [[N_VEC]]
23; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]
24; CHECK:       vector.body:
25; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
26; CHECK-NEXT:    [[TMP0:%.*]] = add i32 [[INDEX]], 0
27; CHECK-NEXT:    [[NEXT_GEP:%.*]] = getelementptr i8, ptr [[PTR]], i32 [[TMP0]]
28; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i8, ptr [[NEXT_GEP]], i32 1
29; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i8, ptr [[TMP1]], i32 0
30; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <16 x i8>, ptr [[TMP2]], align 1
31; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr i8, ptr [[NEXT_GEP]], i32 0
32; CHECK-NEXT:    store <16 x i8> [[WIDE_LOAD]], ptr [[TMP3]], align 1
33; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 16
34; CHECK-NEXT:    [[TMP4:%.*]] = icmp eq i32 [[INDEX_NEXT]], [[N_VEC]]
35; CHECK-NEXT:    br i1 [[TMP4]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
36; CHECK:       middle.block:
37; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i32 [[SIZE]], [[N_VEC]]
38; CHECK-NEXT:    br i1 [[CMP_N]], label [[END:%.*]], label [[SCALAR_PH]]
39; CHECK:       scalar.ph:
40; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i32 [ [[IND_END]], [[MIDDLE_BLOCK]] ], [ [[SIZE]], [[HEADER:%.*]] ]
41; CHECK-NEXT:    [[BC_RESUME_VAL2:%.*]] = phi ptr [ [[IND_END1]], [[MIDDLE_BLOCK]] ], [ [[PTR]], [[HEADER]] ]
42; CHECK-NEXT:    br label [[BODY:%.*]]
43; CHECK:       body:
44; CHECK-NEXT:    [[DEC66:%.*]] = phi i32 [ [[DEC:%.*]], [[BODY]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ]
45; CHECK-NEXT:    [[BUFF:%.*]] = phi ptr [ [[INCDEC_PTR:%.*]], [[BODY]] ], [ [[BC_RESUME_VAL2]], [[SCALAR_PH]] ]
46; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds i8, ptr [[BUFF]], i32 1
47; CHECK-NEXT:    [[DEC]] = add nsw i32 [[DEC66]], -1
48; CHECK-NEXT:    [[TMP5:%.*]] = load i8, ptr [[INCDEC_PTR]], align 1
49; CHECK-NEXT:    store i8 [[TMP5]], ptr [[BUFF]], align 1
50; CHECK-NEXT:    [[TOBOOL11:%.*]] = icmp eq i32 [[DEC]], 0
51; CHECK-NEXT:    br i1 [[TOBOOL11]], label [[END]], label [[BODY]], !llvm.loop [[LOOP2:![0-9]+]]
52; CHECK:       end:
53; CHECK-NEXT:    [[INCDEC_PTR_LCSSA:%.*]] = phi ptr [ [[INCDEC_PTR]], [[BODY]] ], [ [[IND_END1]], [[MIDDLE_BLOCK]] ]
54; CHECK-NEXT:    store ptr [[INCDEC_PTR_LCSSA]], ptr [[POS]], align 4
55; CHECK-NEXT:    ret void
56;
57header:
58  %ptr0 = load ptr, ptr %pos, align 4
59  br label %body
60
61body:
62  %dec66 = phi i32 [ %dec, %body ], [ %size, %header ]
63  %buff = phi ptr [ %incdec.ptr, %body ], [ %ptr, %header ]
64  %incdec.ptr = getelementptr inbounds i8, ptr %buff, i32 1
65  %dec = add nsw i32 %dec66, -1
66  %0 = load i8, ptr %incdec.ptr, align 1
67  store i8 %0, ptr %buff, align 1
68  %tobool11 = icmp eq i32 %dec, 0
69  br i1 %tobool11, label %end, label %body
70
71end:
72  store ptr %incdec.ptr, ptr %pos, align 4
73  ret void
74}
75