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1; This test makes sure that div instructions are properly eliminated.
2
3; RUN: opt < %s -instcombine -S | FileCheck %s
4
5define i32 @test1(i32 %A) {
6        %B = sdiv i32 %A, 1             ; <i32> [#uses=1]
7        ret i32 %B
8; CHECK-LABEL: @test1(
9; CHECK-NEXT: ret i32 %A
10}
11
12define i32 @test2(i32 %A) {
13        ; => Shift
14        %B = udiv i32 %A, 8             ; <i32> [#uses=1]
15        ret i32 %B
16; CHECK-LABEL: @test2(
17; CHECK-NEXT: lshr i32 %A, 3
18}
19
20define i32 @test3(i32 %A) {
21        ; => 0, don't need to keep traps
22        %B = sdiv i32 0, %A             ; <i32> [#uses=1]
23        ret i32 %B
24; CHECK-LABEL: @test3(
25; CHECK-NEXT: ret i32 0
26}
27
28define i32 @test4(i32 %A) {
29        ; 0-A
30        %B = sdiv i32 %A, -1            ; <i32> [#uses=1]
31        ret i32 %B
32; CHECK-LABEL: @test4(
33; CHECK-NEXT: sub i32 0, %A
34}
35
36define i32 @test5(i32 %A) {
37        %B = udiv i32 %A, -16           ; <i32> [#uses=1]
38        %C = udiv i32 %B, -4            ; <i32> [#uses=1]
39        ret i32 %C
40; CHECK-LABEL: @test5(
41; CHECK-NEXT: ret i32 0
42}
43
44define i1 @test6(i32 %A) {
45        %B = udiv i32 %A, 123           ; <i32> [#uses=1]
46        ; A < 123
47        %C = icmp eq i32 %B, 0          ; <i1> [#uses=1]
48        ret i1 %C
49; CHECK-LABEL: @test6(
50; CHECK-NEXT: icmp ult i32 %A, 123
51}
52
53define i1 @test7(i32 %A) {
54        %B = udiv i32 %A, 10            ; <i32> [#uses=1]
55        ; A >= 20 && A < 30
56        %C = icmp eq i32 %B, 2          ; <i1> [#uses=1]
57        ret i1 %C
58; CHECK-LABEL: @test7(
59; CHECK-NEXT: add i32 %A, -20
60; CHECK-NEXT: icmp ult i32
61}
62
63define i1 @test8(i8 %A) {
64        %B = udiv i8 %A, 123            ; <i8> [#uses=1]
65        ; A >= 246
66        %C = icmp eq i8 %B, 2           ; <i1> [#uses=1]
67        ret i1 %C
68; CHECK-LABEL: @test8(
69; CHECK-NEXT: icmp ugt i8 %A, -11
70}
71
72define i1 @test9(i8 %A) {
73        %B = udiv i8 %A, 123            ; <i8> [#uses=1]
74        ; A < 246
75        %C = icmp ne i8 %B, 2           ; <i1> [#uses=1]
76        ret i1 %C
77; CHECK-LABEL: @test9(
78; CHECK-NEXT: icmp ult i8 %A, -10
79}
80
81define i32 @test10(i32 %X, i1 %C) {
82        %V = select i1 %C, i32 64, i32 8                ; <i32> [#uses=1]
83        %R = udiv i32 %X, %V            ; <i32> [#uses=1]
84        ret i32 %R
85; CHECK-LABEL: @test10(
86; CHECK-NEXT: select i1 %C, i32 6, i32 3
87; CHECK-NEXT: lshr i32 %X
88}
89
90define i32 @test11(i32 %X, i1 %C) {
91        %A = select i1 %C, i32 1024, i32 32             ; <i32> [#uses=1]
92        %B = udiv i32 %X, %A            ; <i32> [#uses=1]
93        ret i32 %B
94; CHECK-LABEL: @test11(
95; CHECK-NEXT: select i1 %C, i32 10, i32 5
96; CHECK-NEXT: lshr i32 %X
97}
98
99; PR2328
100define i32 @test12(i32 %x) nounwind  {
101	%tmp3 = udiv i32 %x, %x		; 1
102	ret i32 %tmp3
103; CHECK-LABEL: @test12(
104; CHECK-NEXT: ret i32 1
105}
106
107define i32 @test13(i32 %x) nounwind  {
108	%tmp3 = sdiv i32 %x, %x		; 1
109	ret i32 %tmp3
110; CHECK-LABEL: @test13(
111; CHECK-NEXT: ret i32 1
112}
113
114define i32 @test14(i8 %x) nounwind {
115	%zext = zext i8 %x to i32
116	%div = udiv i32 %zext, 257	; 0
117	ret i32 %div
118; CHECK-LABEL: @test14(
119; CHECK-NEXT: ret i32 0
120}
121
122; PR9814
123define i32 @test15(i32 %a, i32 %b) nounwind {
124  %shl = shl i32 1, %b
125  %div = lshr i32 %shl, 2
126  %div2 = udiv i32 %a, %div
127  ret i32 %div2
128; CHECK-LABEL: @test15(
129; CHECK-NEXT: add i32 %b, -2
130; CHECK-NEXT: lshr i32 %a,
131; CHECK-NEXT: ret i32
132}
133
134define <2 x i64> @test16(<2 x i64> %x) nounwind {
135  %shr = lshr <2 x i64> %x, <i64 5, i64 5>
136  %div = udiv <2 x i64> %shr, <i64 6, i64 6>
137  ret <2 x i64> %div
138; CHECK-LABEL: @test16(
139; CHECK-NEXT: udiv <2 x i64> %x, <i64 192, i64 192>
140; CHECK-NEXT: ret <2 x i64>
141}
142
143define <2 x i64> @test17(<2 x i64> %x) nounwind {
144  %neg = sub nsw <2 x i64> zeroinitializer, %x
145  %div = sdiv <2 x i64> %neg, <i64 3, i64 4>
146  ret <2 x i64> %div
147; CHECK-LABEL: @test17(
148; CHECK-NEXT: sdiv <2 x i64> %x, <i64 -3, i64 -4>
149; CHECK-NEXT: ret <2 x i64>
150}
151
152define <2 x i64> @test18(<2 x i64> %x) nounwind {
153  %div = sdiv <2 x i64> %x, <i64 -1, i64 -1>
154  ret <2 x i64> %div
155; CHECK-LABEL: @test18(
156; CHECK-NEXT: sub <2 x i64> zeroinitializer, %x
157; CHECK-NEXT: ret <2 x i64>
158}
159
160define i32 @test19(i32 %x) {
161  %A = udiv i32 1, %x
162  ret i32 %A
163; CHECK-LABEL: @test19(
164; CHECK-NEXT: icmp eq i32 %x, 1
165; CHECK-NEXT: zext i1 %{{.*}} to i32
166; CHECK-NEXT: ret i32
167}
168
169define i32 @test20(i32 %x) {
170  %A = sdiv i32 1, %x
171  ret i32 %A
172; CHECK-LABEL: @test20(
173; CHECK-NEXT: add i32 %x, 1
174; CHECK-NEXT: icmp ult i32 %{{.*}}, 3
175; CHECK-NEXT: select i1 %{{.*}}, i32 %x, i32 {{.*}}
176; CHECK-NEXT: ret i32
177}
178
179define i32 @test21(i32 %a) {
180  %shl = shl nsw i32 %a, 2
181  %div = sdiv i32 %shl, 12
182  ret i32 %div
183; CHECK-LABEL: @test21(
184; CHECK-NEXT: %div = sdiv i32 %a, 3
185; CHECK-NEXT: ret i32 %div
186}
187
188define i32 @test22(i32 %a) {
189  %mul = mul nsw i32 %a, 3
190  %div = sdiv i32 %mul, 12
191  ret i32 %div
192; CHECK-LABEL: @test22(
193; CHECK-NEXT: %div = sdiv i32 %a, 4
194; CHECK-NEXT: ret i32 %div
195}
196
197define i32 @test23(i32 %a) {
198  %shl = shl nuw i32 %a, 2
199  %div = udiv i32 %shl, 12
200  ret i32 %div
201; CHECK-LABEL: @test23(
202; CHECK-NEXT: %div = udiv i32 %a, 3
203; CHECK-NEXT: ret i32 %div
204}
205
206define i32 @test24(i32 %a) {
207  %mul = mul nuw i32 %a, 3
208  %div = udiv i32 %mul, 12
209  ret i32 %div
210; CHECK-LABEL: @test24(
211; CHECK-NEXT: %div = lshr i32 %a, 2
212; CHECK-NEXT: ret i32 %div
213}
214
215define i32 @test25(i32 %a) {
216  %shl = shl nsw i32 %a, 2
217  %div = sdiv i32 %shl, 2
218  ret i32 %div
219; CHECK-LABEL: @test25(
220; CHECK-NEXT: %div = shl nsw i32 %a, 1
221; CHECK-NEXT: ret i32 %div
222}
223
224define i32 @test26(i32 %a) {
225  %mul = mul nsw i32 %a, 12
226  %div = sdiv i32 %mul, 3
227  ret i32 %div
228; CHECK-LABEL: @test26(
229; CHECK-NEXT: %div = shl nsw i32 %a, 2
230; CHECK-NEXT: ret i32 %div
231}
232
233define i32 @test27(i32 %a) {
234  %shl = shl nuw i32 %a, 2
235  %div = udiv i32 %shl, 2
236  ret i32 %div
237; CHECK-LABEL: @test27(
238; CHECK-NEXT: %div = shl nuw i32 %a, 1
239; CHECK-NEXT: ret i32 %div
240}
241
242define i32 @test28(i32 %a) {
243  %mul = mul nuw i32 %a, 36
244  %div = udiv i32 %mul, 3
245  ret i32 %div
246; CHECK-LABEL: @test28(
247; CHECK-NEXT: %div = mul nuw i32 %a, 12
248; CHECK-NEXT: ret i32 %div
249}
250
251define i32 @test29(i32 %a) {
252  %mul = shl nsw i32 %a, 31
253  %div = sdiv i32 %mul, -2147483648
254  ret i32 %div
255; CHECK-LABEL: @test29(
256; CHECK-NEXT: %[[and:.*]] = and i32 %a, 1
257; CHECK-NEXT: ret i32 %[[and]]
258}
259
260define i32 @test30(i32 %a) {
261  %mul = shl nuw i32 %a, 31
262  %div = udiv i32 %mul, -2147483648
263  ret i32 %div
264; CHECK-LABEL: @test30(
265; CHECK-NEXT: ret i32 %a
266}
267
268define <2 x i32> @test31(<2 x i32> %x) {
269  %shr = lshr <2 x i32> %x, <i32 31, i32 31>
270  %div = udiv <2 x i32> %shr, <i32 2147483647, i32 2147483647>
271  ret <2 x i32> %div
272; CHECK-LABEL: @test31(
273; CHECK-NEXT: ret <2 x i32> zeroinitializer
274}
275
276define i32 @test32(i32 %a, i32 %b) {
277  %shl = shl i32 2, %b
278  %div = lshr i32 %shl, 2
279  %div2 = udiv i32 %a, %div
280  ret i32 %div2
281; CHECK-LABEL: @test32(
282; CHECK-NEXT: %[[shl:.*]] = shl i32 2, %b
283; CHECK-NEXT: %[[shr:.*]] = lshr i32 %[[shl]], 2
284; CHECK-NEXT: %[[div:.*]] = udiv i32 %a, %[[shr]]
285; CHECK-NEXT: ret i32
286}
287
288define <2 x i64> @test33(<2 x i64> %x) nounwind {
289  %shr = lshr exact <2 x i64> %x, <i64 5, i64 5>
290  %div = udiv exact <2 x i64> %shr, <i64 6, i64 6>
291  ret <2 x i64> %div
292; CHECK-LABEL: @test33(
293; CHECK-NEXT: udiv exact <2 x i64> %x, <i64 192, i64 192>
294; CHECK-NEXT: ret <2 x i64>
295}
296
297define <2 x i64> @test34(<2 x i64> %x) nounwind {
298  %neg = sub nsw <2 x i64> zeroinitializer, %x
299  %div = sdiv exact <2 x i64> %neg, <i64 3, i64 4>
300  ret <2 x i64> %div
301; CHECK-LABEL: @test34(
302; CHECK-NEXT: sdiv exact <2 x i64> %x, <i64 -3, i64 -4>
303; CHECK-NEXT: ret <2 x i64>
304}
305
306define i32 @test35(i32 %A) {
307  %and = and i32 %A, 2147483647
308  %mul = sdiv exact i32 %and, 2147483647
309  ret i32 %mul
310; CHECK-LABEL: @test35(
311; CHECK-NEXT: %[[and:.*]]  = and i32 %A, 2147483647
312; CHECK-NEXT: %[[udiv:.*]] = udiv exact i32 %[[and]], 2147483647
313; CHECK-NEXT: ret i32 %[[udiv]]
314}
315
316define i32 @test36(i32 %A) {
317  %and = and i32 %A, 2147483647
318  %shl = shl nsw i32 1, %A
319  %mul = sdiv exact i32 %and, %shl
320  ret i32 %mul
321; CHECK-LABEL: @test36(
322; CHECK-NEXT: %[[and:.*]] = and i32 %A, 2147483647
323; CHECK-NEXT: %[[shr:.*]] = lshr exact i32 %[[and]], %A
324; CHECK-NEXT: ret i32 %[[shr]]
325}
326
327define i32 @test37(i32* %b) {
328entry:
329  store i32 0, i32* %b, align 4
330  %0 = load i32, i32* %b, align 4
331  br i1 undef, label %lor.rhs, label %lor.end
332
333lor.rhs:                                          ; preds = %entry
334  %mul = mul nsw i32 undef, %0
335  br label %lor.end
336
337lor.end:                                          ; preds = %lor.rhs, %entry
338  %t.0 = phi i32 [ %0, %entry ], [ %mul, %lor.rhs ]
339  %div = sdiv i32 %t.0, 2
340  ret i32 %div
341; CHECK-LABEL: @test37(
342; CHECK: ret i32 0
343}
344