xref: /llvm-project/llvm/test/Transforms/LoopUnroll/peel-loop.ll (revision f7685af4a5bd188e6d548967d818d8569f10a70d)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
2; RUN: opt < %s -S -passes=loop-unroll,simplifycfg,instcombine -unroll-force-peel-count=3 -verify-dom-info -simplifycfg-require-and-preserve-domtree=1 | FileCheck %s
3; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll,simplifycfg,instcombine' -unroll-force-peel-count=3 -verify-dom-info | FileCheck %s
4; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop-unroll<peeling;no-runtime>,simplifycfg,instcombine' -unroll-force-peel-count=3 -verify-dom-info | FileCheck %s
5
6; Basic loop peeling - check that we can peel-off the first 3 loop iterations
7; when explicitly requested.
8define void @basic(ptr %p, i32 %k) #0 {
9; CHECK-LABEL: define void @basic(
10; CHECK-SAME: ptr [[P:%.*]], i32 [[K:%.*]]) {
11; CHECK-NEXT:  entry:
12; CHECK-NEXT:    [[CMP3:%.*]] = icmp sgt i32 [[K]], 0
13; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_BODY_PEEL:%.*]], label [[FOR_END:%.*]]
14; CHECK:       for.body.peel:
15; CHECK-NEXT:    store i32 0, ptr [[P]], align 4
16; CHECK-NEXT:    [[CMP_PEEL_NOT:%.*]] = icmp eq i32 [[K]], 1
17; CHECK-NEXT:    br i1 [[CMP_PEEL_NOT]], label [[FOR_END]], label [[FOR_BODY_PEEL2:%.*]]
18; CHECK:       for.body.peel2:
19; CHECK-NEXT:    [[INCDEC_PTR_PEEL:%.*]] = getelementptr inbounds nuw i8, ptr [[P]], i64 4
20; CHECK-NEXT:    store i32 1, ptr [[INCDEC_PTR_PEEL]], align 4
21; CHECK-NEXT:    [[CMP_PEEL5:%.*]] = icmp sgt i32 [[K]], 2
22; CHECK-NEXT:    br i1 [[CMP_PEEL5]], label [[FOR_BODY_PEEL7:%.*]], label [[FOR_END]]
23; CHECK:       for.body.peel7:
24; CHECK-NEXT:    [[INCDEC_PTR_PEEL3:%.*]] = getelementptr inbounds nuw i8, ptr [[P]], i64 8
25; CHECK-NEXT:    [[INCDEC_PTR_PEEL8:%.*]] = getelementptr inbounds nuw i8, ptr [[P]], i64 12
26; CHECK-NEXT:    store i32 2, ptr [[INCDEC_PTR_PEEL3]], align 4
27; CHECK-NEXT:    [[CMP_PEEL10_NOT:%.*]] = icmp eq i32 [[K]], 3
28; CHECK-NEXT:    br i1 [[CMP_PEEL10_NOT]], label [[FOR_END]], label [[FOR_BODY:%.*]]
29; CHECK:       for.body:
30; CHECK-NEXT:    [[I_05:%.*]] = phi i32 [ [[INC:%.*]], [[FOR_BODY]] ], [ 3, [[FOR_BODY_PEEL7]] ]
31; CHECK-NEXT:    [[P_ADDR_04:%.*]] = phi ptr [ [[INCDEC_PTR:%.*]], [[FOR_BODY]] ], [ [[INCDEC_PTR_PEEL8]], [[FOR_BODY_PEEL7]] ]
32; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds nuw i8, ptr [[P_ADDR_04]], i64 4
33; CHECK-NEXT:    store i32 [[I_05]], ptr [[P_ADDR_04]], align 4
34; CHECK-NEXT:    [[INC]] = add nuw nsw i32 [[I_05]], 1
35; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[INC]], [[K]]
36; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[FOR_END]], !llvm.loop [[LOOP0:![0-9]+]]
37; CHECK:       for.end:
38; CHECK-NEXT:    ret void
39;
40entry:
41  %cmp3 = icmp slt i32 0, %k
42  br i1 %cmp3, label %for.body.lr.ph, label %for.end
43
44for.body.lr.ph:                                   ; preds = %entry
45  br label %for.body
46
47for.body:                                         ; preds = %for.body.lr.ph, %for.body
48  %i.05 = phi i32 [ 0, %for.body.lr.ph ], [ %inc, %for.body ]
49  %p.addr.04 = phi ptr [ %p, %for.body.lr.ph ], [ %incdec.ptr, %for.body ]
50  %incdec.ptr = getelementptr inbounds i32, ptr %p.addr.04, i32 1
51  store i32 %i.05, ptr %p.addr.04, align 4
52  %inc = add nsw i32 %i.05, 1
53  %cmp = icmp slt i32 %inc, %k
54  br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge, !llvm.loop !1
55
56for.cond.for.end_crit_edge:                       ; preds = %for.body
57  br label %for.end
58
59for.end:                                          ; preds = %for.cond.for.end_crit_edge, %entry
60  ret void
61}
62
63!1 = distinct !{!1}
64
65; Make sure peeling works correctly when a value defined in a loop is used
66; in later code - we need to correctly plumb the phi depending on which
67; iteration is actually used.
68define i32 @output(ptr %p, i32 %k) #0 {
69; CHECK-LABEL: define i32 @output(
70; CHECK-SAME: ptr [[P:%.*]], i32 [[K:%.*]]) {
71; CHECK-NEXT:  entry:
72; CHECK-NEXT:    [[CMP3:%.*]] = icmp sgt i32 [[K]], 0
73; CHECK-NEXT:    br i1 [[CMP3]], label [[FOR_BODY_PEEL:%.*]], label [[FOR_END:%.*]]
74; CHECK:       for.body.peel:
75; CHECK-NEXT:    store i32 0, ptr [[P]], align 4
76; CHECK-NEXT:    [[CMP_PEEL_NOT:%.*]] = icmp eq i32 [[K]], 1
77; CHECK-NEXT:    br i1 [[CMP_PEEL_NOT]], label [[FOR_END]], label [[FOR_BODY_PEEL2:%.*]]
78; CHECK:       for.body.peel2:
79; CHECK-NEXT:    [[INCDEC_PTR_PEEL:%.*]] = getelementptr inbounds nuw i8, ptr [[P]], i64 4
80; CHECK-NEXT:    store i32 1, ptr [[INCDEC_PTR_PEEL]], align 4
81; CHECK-NEXT:    [[CMP_PEEL5:%.*]] = icmp sgt i32 [[K]], 2
82; CHECK-NEXT:    br i1 [[CMP_PEEL5]], label [[FOR_BODY_PEEL7:%.*]], label [[FOR_END]]
83; CHECK:       for.body.peel7:
84; CHECK-NEXT:    [[INCDEC_PTR_PEEL3:%.*]] = getelementptr inbounds nuw i8, ptr [[P]], i64 8
85; CHECK-NEXT:    [[INCDEC_PTR_PEEL8:%.*]] = getelementptr inbounds nuw i8, ptr [[P]], i64 12
86; CHECK-NEXT:    store i32 2, ptr [[INCDEC_PTR_PEEL3]], align 4
87; CHECK-NEXT:    [[CMP_PEEL10_NOT:%.*]] = icmp eq i32 [[K]], 3
88; CHECK-NEXT:    br i1 [[CMP_PEEL10_NOT]], label [[FOR_END]], label [[FOR_BODY:%.*]]
89; CHECK:       for.body:
90; CHECK-NEXT:    [[I_05:%.*]] = phi i32 [ [[INC:%.*]], [[FOR_BODY]] ], [ 3, [[FOR_BODY_PEEL7]] ]
91; CHECK-NEXT:    [[P_ADDR_04:%.*]] = phi ptr [ [[INCDEC_PTR:%.*]], [[FOR_BODY]] ], [ [[INCDEC_PTR_PEEL8]], [[FOR_BODY_PEEL7]] ]
92; CHECK-NEXT:    [[INCDEC_PTR]] = getelementptr inbounds nuw i8, ptr [[P_ADDR_04]], i64 4
93; CHECK-NEXT:    store i32 [[I_05]], ptr [[P_ADDR_04]], align 4
94; CHECK-NEXT:    [[INC]] = add nuw nsw i32 [[I_05]], 1
95; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[INC]], [[K]]
96; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[FOR_END]], !llvm.loop [[LOOP3:![0-9]+]]
97; CHECK:       for.end:
98; CHECK-NEXT:    [[RET:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ 1, [[FOR_BODY_PEEL]] ], [ 2, [[FOR_BODY_PEEL2]] ], [ 3, [[FOR_BODY_PEEL7]] ], [ [[INC]], [[FOR_BODY]] ]
99; CHECK-NEXT:    ret i32 [[RET]]
100;
101entry:
102  %cmp3 = icmp slt i32 0, %k
103  br i1 %cmp3, label %for.body.lr.ph, label %for.end
104
105for.body.lr.ph:                                   ; preds = %entry
106  br label %for.body
107
108for.body:                                         ; preds = %for.body.lr.ph, %for.body
109  %i.05 = phi i32 [ 0, %for.body.lr.ph ], [ %inc, %for.body ]
110  %p.addr.04 = phi ptr [ %p, %for.body.lr.ph ], [ %incdec.ptr, %for.body ]
111  %incdec.ptr = getelementptr inbounds i32, ptr %p.addr.04, i32 1
112  store i32 %i.05, ptr %p.addr.04, align 4
113  %inc = add nsw i32 %i.05, 1
114  %cmp = icmp slt i32 %inc, %k
115  br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge, !llvm.loop !2
116
117for.cond.for.end_crit_edge:                       ; preds = %for.body
118  br label %for.end
119
120for.end:                                          ; preds = %for.cond.for.end_crit_edge, %entry
121  %ret = phi i32 [ 0, %entry], [ %inc, %for.cond.for.end_crit_edge ]
122  ret i32 %ret
123}
124
125!2 = distinct !{!2}
126;.
127; CHECK: [[LOOP0]] = distinct !{[[LOOP0]], [[META1:![0-9]+]], [[META2:![0-9]+]]}
128; CHECK: [[META1]] = !{!"llvm.loop.peeled.count", i32 3}
129; CHECK: [[META2]] = !{!"llvm.loop.unroll.disable"}
130; CHECK: [[LOOP3]] = distinct !{[[LOOP3]], [[META1]], [[META2]]}
131;.
132