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1; RUN: opt < %s -indvars -enable-iv-rewrite=false -S | FileCheck %s
2
3target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
4
5; IV with constant start, preinc and postinc sign extends, with and without NSW.
6; IV rewrite only removes one sext. WidenIVs removes all three.
7define void @postincConstIV(i8* %base, i32 %limit) nounwind {
8entry:
9  br label %loop
10; CHECK: loop:
11; CHECK-NOT: sext
12; CHECK: exit:
13loop:
14  %iv = phi i32 [ %postiv, %loop ], [ 0, %entry ]
15  %ivnsw = phi i32 [ %postivnsw, %loop ], [ 0, %entry ]
16  %preofs = sext i32 %iv to i64
17  %preadr = getelementptr i8* %base, i64 %preofs
18  store i8 0, i8* %preadr
19  %postiv = add i32 %iv, 1
20  %postofs = sext i32 %postiv to i64
21  %postadr = getelementptr i8* %base, i64 %postofs
22  store i8 0, i8* %postadr
23  %postivnsw = add nsw i32 %ivnsw, 1
24  %postofsnsw = sext i32 %postivnsw to i64
25  %postadrnsw = getelementptr i8* %base, i64 %postofsnsw
26  store i8 0, i8* %postadrnsw
27  %cond = icmp sgt i32 %limit, %iv
28  br i1 %cond, label %loop, label %exit
29exit:
30  br label %return
31return:
32  ret void
33}
34
35; IV with nonconstant start, preinc and postinc sign extends,
36; with and without NSW.
37; As with postincConstIV, WidenIVs removes all three sexts.
38define void @postincVarIV(i8* %base, i32 %init, i32 %limit) nounwind {
39entry:
40  %precond = icmp sgt i32 %limit, %init
41  br i1 %precond, label %loop, label %return
42; CHECK: loop:
43; CHECK-NOT: sext
44; CHECK: exit:
45loop:
46  %iv = phi i32 [ %postiv, %loop ], [ %init, %entry ]
47  %ivnsw = phi i32 [ %postivnsw, %loop ], [ %init, %entry ]
48  %preofs = sext i32 %iv to i64
49  %preadr = getelementptr i8* %base, i64 %preofs
50  store i8 0, i8* %preadr
51  %postiv = add i32 %iv, 1
52  %postofs = sext i32 %postiv to i64
53  %postadr = getelementptr i8* %base, i64 %postofs
54  store i8 0, i8* %postadr
55  %postivnsw = add nsw i32 %ivnsw, 1
56  %postofsnsw = sext i32 %postivnsw to i64
57  %postadrnsw = getelementptr i8* %base, i64 %postofsnsw
58  store i8 0, i8* %postadrnsw
59  %cond = icmp sgt i32 %limit, %postiv
60  br i1 %cond, label %loop, label %exit
61exit:
62  br label %return
63return:
64  ret void
65}
66
67; Test sign extend elimination in the inner and outer loop.
68; %outercount is straightforward to widen, besides being in an outer loop.
69; %innercount is currently blocked by lcssa, so is not widened.
70; %inneriv can be widened only after proving it has no signed-overflow
71;   based on the loop test.
72define void @nestedIV(i8* %address, i32 %limit) nounwind {
73entry:
74  %limitdec = add i32 %limit, -1
75  br label %outerloop
76
77; CHECK: outerloop:
78;
79; Eliminate %ofs1 after widening outercount.
80; CHECK-NOT: sext
81; CHECK: getelementptr
82;
83; IV rewriting hoists a gep into this block. We don't like that.
84; CHECK-NOT: getelementptr
85outerloop:
86  %outercount   = phi i32 [ %outerpostcount, %outermerge ], [ 0, %entry ]
87  %innercount = phi i32 [ %innercount.merge, %outermerge ], [ 0, %entry ]
88
89  %outercountdec = add i32 %outercount, -1
90  %ofs1 = sext i32 %outercountdec to i64
91  %adr1 = getelementptr i8* %address, i64 %ofs1
92  store i8 0, i8* %adr1
93
94  br label %innerpreheader
95
96innerpreheader:
97  %innerprecmp = icmp sgt i32 %limitdec, %innercount
98  br i1 %innerprecmp, label %innerloop, label %outermerge
99
100; CHECK: innerloop:
101;
102; Eliminate %ofs2 after widening inneriv.
103; Eliminate %ofs3 after normalizing sext(innerpostiv)
104; CHECK-NOT: sext
105; CHECK: getelementptr
106;
107; FIXME: We should check that indvars does not increase the number of
108; IVs in this loop. sext elimination plus LFTR currently results in 2 final
109; IVs. Waiting to remove LFTR.
110innerloop:
111  %inneriv = phi i32 [ %innerpostiv, %innerloop ], [ %innercount, %innerpreheader ]
112  %innerpostiv = add i32 %inneriv, 1
113
114  %ofs2 = sext i32 %inneriv to i64
115  %adr2 = getelementptr i8* %address, i64 %ofs2
116  store i8 0, i8* %adr2
117
118  %ofs3 = sext i32 %innerpostiv to i64
119  %adr3 = getelementptr i8* %address, i64 %ofs3
120  store i8 0, i8* %adr3
121
122  %innercmp = icmp sgt i32 %limitdec, %innerpostiv
123  br i1 %innercmp, label %innerloop, label %innerexit
124
125innerexit:
126  %innercount.lcssa = phi i32 [ %innerpostiv, %innerloop ]
127  br label %outermerge
128
129; CHECK: outermerge:
130;
131; Eliminate %ofs4 after widening outercount
132; CHECK-NOT: sext
133; CHECK: getelementptr
134;
135; TODO: Eliminate %ofs5 after removing lcssa
136outermerge:
137  %innercount.merge = phi i32 [ %innercount.lcssa, %innerexit ], [ %innercount, %innerpreheader ]
138
139  %ofs4 = sext i32 %outercount to i64
140  %adr4 = getelementptr i8* %address, i64 %ofs4
141  store i8 0, i8* %adr4
142
143  %ofs5 = sext i32 %innercount.merge to i64
144  %adr5 = getelementptr i8* %address, i64 %ofs5
145  store i8 0, i8* %adr5
146
147  %outerpostcount = add i32 %outercount, 1
148  %tmp47 = icmp slt i32 %outerpostcount, %limit
149  br i1 %tmp47, label %outerloop, label %return
150
151return:
152  ret void
153}
154