1; RUN: opt -loop-vectorize -scalable-vectorization=on -force-vector-width=4 -force-vector-interleave=1 -force-target-supports-scalable-vectors=true -S < %s | FileCheck %s --check-prefix=CHECK-VF4UF1
2; RUN: opt -loop-vectorize -scalable-vectorization=on -force-vector-width=4 -force-vector-interleave=2 -force-target-supports-scalable-vectors=true -S < %s | FileCheck %s --check-prefix=CHECK-VF4UF2
3
4; void recurrence_1(int *a, int *b, int n) {
5;   for(int i = 0; i < n; i++)
6;     b[i] =  a[i] + a[i - 1]
7; }
8;
9define void @recurrence_1(i32* nocapture readonly %a, i32* nocapture %b, i32 %n) {
10; CHECK-VF4UF1-LABEL: @recurrence_1
11; CHECK-VF4UF1: for.preheader
12; CHECK-VF4UF1: %[[SUB_1:.*]] = add i32 %n, -1
13; CHECK-VF4UF1: %[[ZEXT:.*]] = zext i32 %[[SUB_1]] to i64
14; CHECK-VF4UF1: %[[ADD:.*]] = add nuw nsw i64 %[[ZEXT]], 1
15; CHECK-VF4UF1: vector.ph:
16; CHECK-VF4UF1: %[[VSCALE1:.*]] = call i32 @llvm.vscale.i32()
17; CHECK-VF4UF1: %[[MUL1:.*]] = mul i32 %[[VSCALE1]], 4
18; CHECK-VF4UF1: %[[SUB1:.*]] = sub i32 %[[MUL1]], 1
19; CHECK-VF4UF1: %[[VEC_RECUR_INIT:.*]] = insertelement <vscale x 4 x i32> poison, i32 %pre_load, i32 %[[SUB1]]
20; CHECK-VF4UF1: vector.body:
21; CHECK-VF4UF1: %[[INDEX:.*]] = phi i64 [ 0, %vector.ph ], [ %[[NEXT_IDX:.*]], %vector.body ]
22; CHECK-VF4UF1: %[[VEC_RECUR:.*]] = phi <vscale x 4 x i32> [ %[[VEC_RECUR_INIT]], %vector.ph ], [ %[[LOAD:.*]], %vector.body ]
23; CHECK-VF4UF1: %[[LOAD]] = load <vscale x 4 x i32>, <vscale x 4 x i32>*
24; CHECK-VF4UF1: %[[SPLICE:.*]] = call <vscale x 4 x i32> @llvm.experimental.vector.splice.nxv4i32(<vscale x 4 x i32> %[[VEC_RECUR]], <vscale x 4 x i32> %[[LOAD]], i32 -1)
25; CHECK-VF4UF1: middle.block:
26; CHECK-VF4UF1: %[[VSCALE2:.*]] = call i32 @llvm.vscale.i32()
27; CHECK-VF4UF1: %[[MUL2:.*]] = mul i32 %[[VSCALE2]], 4
28; CHECK-VF4UF1: %[[SUB2:.*]] = sub i32 %[[MUL2]], 1
29; CHECK-VF4UF1: %[[VEC_RECUR_EXT:.*]] = extractelement <vscale x 4 x i32> %[[LOAD]], i32 %[[SUB2]]
30; CHECK-VF4UF1: %[[VSCALE3:.*]] = call i32 @llvm.vscale.i32()
31; CHECK-VF4UF1: %[[MUL3:.*]] = mul i32 %[[VSCALE3]], 4
32; CHECK-VF4UF1: %[[SUB3:.*]] = sub i32 %[[MUL3]], 2
33; CHECK-VF4UF1: %[[VEC_RECUR_FOR_PHI:.*]] =  extractelement <vscale x 4 x i32> %[[LOAD]], i32 %[[SUB3]]
34entry:
35  br label %for.preheader
36
37for.preheader:
38  %arrayidx.phi.trans.insert = getelementptr inbounds i32, i32* %a, i64 0
39  %pre_load = load i32, i32* %arrayidx.phi.trans.insert
40  br label %scalar.body
41
42scalar.body:
43  %0 = phi i32 [ %pre_load, %for.preheader ], [ %1, %scalar.body ]
44  %indvars.iv = phi i64 [ 0, %for.preheader ], [ %indvars.iv.next, %scalar.body ]
45  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
46  %arrayidx32 = getelementptr inbounds i32, i32* %a, i64 %indvars.iv.next
47  %1 = load i32, i32* %arrayidx32
48  %arrayidx34 = getelementptr inbounds i32, i32* %b, i64 %indvars.iv
49  %add35 = add i32 %1, %0
50  store i32 %add35, i32* %arrayidx34
51  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
52  %exitcond = icmp eq i32 %lftr.wideiv, %n
53  br i1 %exitcond, label %for.exit, label %scalar.body, !llvm.loop !0
54
55for.exit:
56  ret void
57}
58
59; int recurrence_2(int *a, int n) {
60;   int minmax;
61;   for (int i = 0; i < n; ++i)
62;     minmax = min(minmax, max(a[i] - a[i-1], 0));
63;   return minmax;
64; }
65;
66define i32 @recurrence_2(i32* nocapture readonly %a, i32 %n) {
67; CHECK-VF4UF1-LABEL: @recurrence_2
68; CHECK-VF4UF1: vector.ph:
69; CHECK-VF4UF1: %[[VSCALE1:.*]] = call i32 @llvm.vscale.i32()
70; CHECK-VF4UF1: %[[MUL1:.*]] = mul i32 %[[VSCALE1]], 4
71; CHECK-VF4UF1: %[[SUB1:.*]] = sub i32 %[[MUL1]], 1
72; CHECK-VF4UF1: %[[VEC_RECUR_INIT:.*]] = insertelement <vscale x 4 x i32> poison, i32 %.pre, i32 %[[SUB1]]
73; CHECK-VF4UF1: vector.body:
74; CHECK-VF4UF1: %[[VEC_RECUR:.*]] = phi <vscale x 4 x i32> [ %[[VEC_RECUR_INIT]], %vector.ph ], [ %[[LOAD:.*]], %vector.body ]
75; CHECK-VF4UF1: %[[LOAD]] = load <vscale x 4 x i32>, <vscale x 4 x i32>*
76; CHECK-VF4UF1: %[[REVERSE:.*]] = call <vscale x 4 x i32> @llvm.experimental.vector.splice.nxv4i32(<vscale x 4 x i32> %[[VEC_RECUR]], <vscale x 4 x i32> %[[LOAD]], i32 -1)
77; CHECK-VF4UF1: middle.block:
78; CHECK-VF4UF1: %[[VSCALE2:.*]] = call i32 @llvm.vscale.i32()
79; CHECK-VF4UF1: %[[MUL2:.*]] = mul i32 %[[VSCALE2]], 4
80; CHECK-VF4UF1: %[[SUB2:.*]] = sub i32 %[[MUL2]], 1
81; CHECK-VF4UF1: %[[VEC_RECUR_EXT:.*]] = extractelement <vscale x 4 x i32> %[[LOAD]], i32 %[[SUB2]]
82entry:
83  %cmp27 = icmp sgt i32 %n, 0
84  br i1 %cmp27, label %for.preheader, label %for.cond.cleanup
85
86for.preheader:
87  %arrayidx2.phi.trans.insert = getelementptr inbounds i32, i32* %a, i64 -1
88  %.pre = load i32, i32* %arrayidx2.phi.trans.insert, align 4
89  br label %scalar.body
90
91for.cond.cleanup.loopexit:
92  %minmax.0.cond.lcssa = phi i32 [ %minmax.0.cond, %scalar.body ]
93  br label %for.cond.cleanup
94
95for.cond.cleanup:
96  %minmax.0.lcssa = phi i32 [ undef, %entry ], [ %minmax.0.cond.lcssa, %for.cond.cleanup.loopexit ]
97  ret i32 %minmax.0.lcssa
98
99scalar.body:
100  %0 = phi i32 [ %.pre, %for.preheader ], [ %1, %scalar.body ]
101  %indvars.iv = phi i64 [ 0, %for.preheader ], [ %indvars.iv.next, %scalar.body ]
102  %minmax.028 = phi i32 [ undef, %for.preheader ], [ %minmax.0.cond, %scalar.body ]
103  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
104  %1 = load i32, i32* %arrayidx, align 4
105  %sub3 = sub nsw i32 %1, %0
106  %cmp4 = icmp sgt i32 %sub3, 0
107  %cond = select i1 %cmp4, i32 %sub3, i32 0
108  %cmp5 = icmp slt i32 %minmax.028, %cond
109  %minmax.0.cond = select i1 %cmp5, i32 %minmax.028, i32 %cond
110  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
111  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
112  %exitcond = icmp eq i32 %lftr.wideiv, %n
113  br i1 %exitcond, label %for.cond.cleanup.loopexit, label %scalar.body, !llvm.loop !0
114}
115
116define void @recurrence_3(i16* nocapture readonly %a, double* nocapture %b, i32 %n, float %f, i16 %p) {
117; CHECK-VF4UF1: vector.ph:
118; CHECK-VF4UF1: %[[VSCALE1:.*]] = call i32 @llvm.vscale.i32()
119; CHECK-VF4UF1: %[[MUL1:.*]] = mul i32 %[[VSCALE1]], 4
120; CHECK-VF4UF1: %[[SUB1:.*]] = sub i32 %[[MUL1]], 1
121; CHECK-VF4UF1: %vector.recur.init = insertelement <vscale x 4 x i16> poison, i16 %0, i32 %[[SUB1]]
122; CHECK-VF4UF1: vector.body:
123; CHECK-VF4UF1: %vector.recur = phi <vscale x 4 x i16> [ %vector.recur.init, %vector.ph ], [ %[[L1:.*]], %vector.body ]
124; CHECK-VF4UF1: %[[L1]] = load <vscale x 4 x i16>, <vscale x 4 x i16>*
125; CHECK-VF4UF1: %[[SPLICE:.*]] = call <vscale x 4 x i16> @llvm.experimental.vector.splice.nxv4i16(<vscale x 4 x i16> %vector.recur, <vscale x 4 x i16> %[[L1]], i32 -1)
126; Check also that the casts were not moved needlessly.
127; CHECK-VF4UF1: sitofp <vscale x 4 x i16> %[[L1]] to <vscale x 4 x double>
128; CHECK-VF4UF1: sitofp <vscale x 4 x i16> %[[SPLICE]] to <vscale x 4 x double>
129; CHECK-VF4UF1: middle.block:
130; CHECK-VF4UF1: %[[VSCALE2:.*]] = call i32 @llvm.vscale.i32()
131; CHECK-VF4UF1: %[[MUL2:.*]] = mul i32 %[[VSCALE2]], 4
132; CHECK-VF4UF1: %[[SUB2:.*]] = sub i32 %[[MUL2]], 1
133; CHECK-VF4UF1: %vector.recur.extract = extractelement <vscale x 4 x i16> %[[L1]], i32 %[[SUB2]]
134entry:
135  %0 = load i16, i16* %a, align 2
136  %conv = sitofp i16 %0 to double
137  %conv1 = fpext float %f to double
138  %conv2 = sitofp i16 %p to double
139  %mul = fmul fast double %conv2, %conv1
140  %sub = fsub fast double %conv, %mul
141  store double %sub, double* %b, align 8
142  %cmp25 = icmp sgt i32 %n, 1
143  br i1 %cmp25, label %for.preheader, label %for.end
144
145for.preheader:
146  br label %scalar.body
147
148scalar.body:
149  %1 = phi i16 [ %0, %for.preheader ], [ %2, %scalar.body ]
150  %iv = phi i64 [ %iv.next, %scalar.body ], [ 1, %for.preheader ]
151  %arrayidx5 = getelementptr inbounds i16, i16* %a, i64 %iv
152  %2 = load i16, i16* %arrayidx5, align 2
153  %conv6 = sitofp i16 %2 to double
154  %conv11 = sitofp i16 %1 to double
155  %mul12 = fmul fast double %conv11, %conv1
156  %sub13 = fsub fast double %conv6, %mul12
157  %arrayidx15 = getelementptr inbounds double, double* %b, i64 %iv
158  store double %sub13, double* %arrayidx15, align 8
159  %iv.next = add nuw nsw i64 %iv, 1
160  %lftr.wideiv = trunc i64 %iv.next to i32
161  %exitcond = icmp eq i32 %lftr.wideiv, %n
162  br i1 %exitcond, label %for.end.loopexit, label %scalar.body, !llvm.loop !0
163
164for.end.loopexit:
165  br label %for.end
166
167for.end:
168  ret void
169}
170
171define void @constant_folded_previous_value() {
172; CHECK-VF4UF2-LABEL: @constant_folded_previous_value
173; CHECK-VF4UF2: vector.body
174; CHECK-VF4UF2: %[[VECTOR_RECUR:.*]] = phi <vscale x 4 x i64> [ %vector.recur.init, %vector.ph ], [ shufflevector (<vscale x 4 x i64> insertelement (<vscale x 4 x i64> poison, i64 1, i32 0), <vscale x 4 x i64> poison, <vscale x 4 x i32> zeroinitializer), %vector.body ]
175; CHECK-VF4UF2: %[[SPLICE1:.*]] = call <vscale x 4 x i64> @llvm.experimental.vector.splice.nxv4i64(<vscale x 4 x i64> %vector.recur, <vscale x 4 x i64> shufflevector (<vscale x 4 x i64> insertelement (<vscale x 4 x i64> poison, i64 1, i32 0), <vscale x 4 x i64> poison, <vscale x 4 x i32> zeroinitializer), i32 -1)
176; CHECK-VF4UF2: %[[SPLICE2:.*]] = call <vscale x 4 x i64> @llvm.experimental.vector.splice.nxv4i64(<vscale x 4 x i64> shufflevector (<vscale x 4 x i64> insertelement (<vscale x 4 x i64> poison, i64 1, i32 0), <vscale x 4 x i64> poison, <vscale x 4 x i32> zeroinitializer), <vscale x 4 x i64> shufflevector (<vscale x 4 x i64> insertelement (<vscale x 4 x i64> poison, i64 1, i32 0), <vscale x 4 x i64> poison, <vscale x 4 x i32> zeroinitializer), i32 -1)
177; CHECK-VF4UF2: br i1 {{.*}}, label %middle.block, label %vector.body
178entry:
179  br label %scalar.body
180
181scalar.body:
182  %i = phi i64 [ 0, %entry ], [ %i.next, %scalar.body ]
183  %tmp2 = phi i64 [ 0, %entry ], [ %tmp3, %scalar.body ]
184  %tmp3 = add i64 0, 1
185  %i.next = add nuw nsw i64 %i, 1
186  %cond = icmp eq i64 %i.next, undef
187  br i1 %cond, label %for.end, label %scalar.body, !llvm.loop !0
188
189for.end:
190  ret void
191}
192
193; We vectorize this first order recurrence, by generating two
194; extracts for the phi `val.phi` - one at the last index and
195; another at the second last index. We need these 2 extracts because
196; the first order recurrence phi is used outside the loop, so we require the phi
197; itself and not its update (addx).
198define i32 @extract_second_last_iteration(i32* %cval, i32 %x)  {
199; CHECK-VF4UF2-LABEL: @extract_second_last_iteration
200; CHECK-VF4UF2: vector.ph
201; CHECK-VF4UF2: call i32 @llvm.vscale.i32()
202; CHECK-VF4UF2: call i32 @llvm.vscale.i32()
203; CHECK-VF4UF2: %[[VSCALE1:.*]] = call i32 @llvm.vscale.i32()
204; CHECK-VF4UF2: %[[MUL1:.*]] = mul i32 %[[VSCALE1]], 4
205; CHECK-VF4UF2: %[[SUB1:.*]] = sub i32 %[[MUL1]], 1
206; CHECK-VF4UF2: %[[VEC_RECUR_INIT:.*]] = insertelement <vscale x 4 x i32> poison, i32 0, i32 %[[SUB1]]
207; CHECK-VF4UF2: %[[SPLAT_INS1:.*]] = insertelement <vscale x 4 x i32> poison, i32 %x, i32 0
208; CHECK-VF4UF2: %[[SPLAT1:.*]] = shufflevector <vscale x 4 x i32> %[[SPLAT_INS1]], <vscale x 4 x i32> poison, <vscale x 4 x i32> zeroinitializer
209; CHECK-VF4UF2: %[[SPLAT_INS2:.*]] = insertelement <vscale x 4 x i32> poison, i32 %x, i32 0
210; CHECK-VF4UF2: %[[SPLAT2:.*]] = shufflevector <vscale x 4 x i32> %[[SPLAT_INS2]], <vscale x 4 x i32> poison, <vscale x 4 x i32> zeroinitializer
211; ; CHECK-VF4UF2: vector.body
212; CHECK-VF4UF2: %[[VEC_RECUR:.*]] = phi <vscale x 4 x i32> [ %[[VEC_RECUR_INIT]], %vector.ph ], [ %[[ADD2:.*]], %vector.body ]
213; CHECK-VF4UF2: %[[ADD1:.*]] = add <vscale x 4 x i32> %{{.*}}, %[[SPLAT1]]
214; CHECK-VF4UF2: %[[ADD2]] = add <vscale x 4 x i32> %{{.*}}, %[[SPLAT2]]
215; CHECK-VF4UF2: middle.block
216; CHECK-VF4UF2: %[[VSCALE2:.*]] = call i32 @llvm.vscale.i32()
217; CHECK-VF4UF2: %[[MUL2:.*]] = mul i32 %[[VSCALE2]], 4
218; CHECK-VF4UF2: %[[SUB2:.*]] = sub i32 %[[MUL2]], 1
219; CHECK-VF4UF2: %vector.recur.extract = extractelement <vscale x 4 x i32> %[[ADD2]], i32 %[[SUB2]]
220; CHECK-VF4UF2: %[[VSCALE3:.*]] = call i32 @llvm.vscale.i32()
221; CHECK-VF4UF2: %[[MUL3:.*]] = mul i32 %[[VSCALE3]], 4
222; CHECK-VF4UF2: %[[SUB3:.*]] = sub i32 %[[MUL3]], 2
223; CHECK-VF4UF2: %vector.recur.extract.for.phi = extractelement <vscale x 4 x i32> %[[ADD2]], i32 %[[SUB3]]
224entry:
225  br label %for.body
226
227for.body:
228  %inc.phi = phi i32 [ 0, %entry ], [ %inc, %for.body ]
229  %val.phi = phi i32 [ 0, %entry ], [ %addx, %for.body ]
230  %inc = add i32 %inc.phi, 1
231  %bc = zext i32 %inc.phi to i64
232  %addx = add i32 %inc.phi, %x
233  %cmp = icmp eq i32 %inc.phi, 95
234  br i1 %cmp, label %for.end, label %for.body, !llvm.loop !0
235
236for.end:
237  ret i32 %val.phi
238}
239
240; void sink_after(short *a, int n, int *b) {
241;   for(int i = 0; i < n; i++)
242;     b[i] = (a[i] * a[i + 1]);
243; }
244
245; Check that the sext sank after the load in the vector loop.
246define void @sink_after(i16* %a, i32* %b, i64 %n) {
247; CHECK-VF4UF1-LABEL: @sink_after
248; CHECK-VF4UF1: vector.body
249; CHECK-VF4UF1: %[[VEC_RECUR:.*]] = phi <vscale x 4 x i16> [ %vector.recur.init, %vector.ph ], [ %[[LOAD:.*]], %vector.body ]
250; CHECK-VF4UF1: %[[LOAD]] = load <vscale x 4 x i16>, <vscale x 4 x i16>*
251; CHECK-VF4UF1-NEXT: %[[SPLICE:.*]] = call <vscale x 4 x i16> @llvm.experimental.vector.splice.nxv4i16(<vscale x 4 x i16> %[[VEC_RECUR]], <vscale x 4 x i16> %[[LOAD]], i32 -1)
252; CHECK-VF4UF1-NEXT: sext <vscale x 4 x i16> %[[SPLICE]] to <vscale x 4 x i32>
253; CHECK-VF4UF1-NEXT: sext <vscale x 4 x i16> %[[LOAD]] to <vscale x 4 x i32>
254entry:
255  %.pre = load i16, i16* %a
256  br label %for.body
257
258for.body:
259  %0 = phi i16 [ %.pre, %entry ], [ %1, %for.body ]
260  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
261  %conv = sext i16 %0 to i32
262  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
263  %arrayidx2 = getelementptr inbounds i16, i16* %a, i64 %indvars.iv.next
264  %1 = load i16, i16* %arrayidx2
265  %conv3 = sext i16 %1 to i32
266  %mul = mul nsw i32 %conv3, %conv
267  %arrayidx5 = getelementptr inbounds i32, i32* %b, i64 %indvars.iv
268  store i32 %mul, i32* %arrayidx5
269  %exitcond = icmp eq i64 %indvars.iv.next, %n
270  br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !0
271
272for.end:
273  ret void
274}
275
276!0 = distinct !{!0, !1}
277!1 = !{!"llvm.loop.vectorize.scalable.enable", i1 true}
278