1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -instcombine -S | FileCheck %s
3
4; https://bugs.llvm.org/show_bug.cgi?id=38123
5
6; Pattern:
7;   x & ((-1 << y) >> y) == x
8; Should be transformed into:
9;   x u<= ((-1 << y) >> y)
10
11; This pattern is uncanonical, but we can not canonicalize it due to extra uses.
12
13declare void @use8(i8)
14declare void @use2i8(<2 x i8>)
15declare void @use3i8(<3 x i8>)
16
17; ============================================================================ ;
18; Basic positive tests
19; ============================================================================ ;
20
21define i1 @p0(i8 %x, i8 %y) {
22; CHECK-LABEL: @p0(
23; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
24; CHECK-NEXT:    call void @use8(i8 [[T0]])
25; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
26; CHECK-NEXT:    [[TMP1:%.*]] = icmp uge i8 [[T1]], [[X:%.*]]
27; CHECK-NEXT:    ret i1 [[TMP1]]
28;
29  %t0 = shl i8 -1, %y
30  call void @use8(i8 %t0)
31  %t1 = lshr i8 %t0, %y
32  %t2 = and i8 %t1, %x
33  %ret = icmp eq i8 %t2, %x
34  ret i1 %ret
35}
36
37; ============================================================================ ;
38; Vector tests
39; ============================================================================ ;
40
41define <2 x i1> @p1_vec(<2 x i8> %x, <2 x i8> %y) {
42; CHECK-LABEL: @p1_vec(
43; CHECK-NEXT:    [[T0:%.*]] = shl <2 x i8> <i8 -1, i8 -1>, [[Y:%.*]]
44; CHECK-NEXT:    call void @use2i8(<2 x i8> [[T0]])
45; CHECK-NEXT:    [[T1:%.*]] = lshr <2 x i8> [[T0]], [[Y]]
46; CHECK-NEXT:    [[TMP1:%.*]] = icmp uge <2 x i8> [[T1]], [[X:%.*]]
47; CHECK-NEXT:    ret <2 x i1> [[TMP1]]
48;
49  %t0 = shl <2 x i8> <i8 -1, i8 -1>, %y
50  call void @use2i8(<2 x i8> %t0)
51  %t1 = lshr <2 x i8> %t0, %y
52  %t2 = and <2 x i8> %t1, %x
53  %ret = icmp eq <2 x i8> %t2, %x
54  ret <2 x i1> %ret
55}
56
57define <3 x i1> @p2_vec_undef0(<3 x i8> %x, <3 x i8> %y) {
58; CHECK-LABEL: @p2_vec_undef0(
59; CHECK-NEXT:    [[T0:%.*]] = shl <3 x i8> <i8 -1, i8 undef, i8 -1>, [[Y:%.*]]
60; CHECK-NEXT:    call void @use3i8(<3 x i8> [[T0]])
61; CHECK-NEXT:    [[T1:%.*]] = lshr <3 x i8> [[T0]], [[Y]]
62; CHECK-NEXT:    [[TMP1:%.*]] = icmp uge <3 x i8> [[T1]], [[X:%.*]]
63; CHECK-NEXT:    ret <3 x i1> [[TMP1]]
64;
65  %t0 = shl <3 x i8> <i8 -1, i8 undef, i8 -1>, %y
66  call void @use3i8(<3 x i8> %t0)
67  %t1 = lshr <3 x i8> %t0, %y
68  %t2 = and <3 x i8> %t1, %x
69  %ret = icmp eq <3 x i8> %t2, %x
70  ret <3 x i1> %ret
71}
72
73; ============================================================================ ;
74; Commutativity tests.
75; ============================================================================ ;
76
77declare i8 @gen8()
78
79define i1 @c0(i8 %y) {
80; CHECK-LABEL: @c0(
81; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
82; CHECK-NEXT:    call void @use8(i8 [[T0]])
83; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
84; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
85; CHECK-NEXT:    [[TMP1:%.*]] = icmp ule i8 [[X]], [[T1]]
86; CHECK-NEXT:    ret i1 [[TMP1]]
87;
88  %t0 = shl i8 -1, %y
89  call void @use8(i8 %t0)
90  %t1 = lshr i8 %t0, %y
91  %x = call i8 @gen8()
92  %t2 = and i8 %x, %t1 ; swapped order
93  %ret = icmp eq i8 %t2, %x
94  ret i1 %ret
95}
96
97define i1 @c1(i8 %y) {
98; CHECK-LABEL: @c1(
99; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
100; CHECK-NEXT:    call void @use8(i8 [[T0]])
101; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
102; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
103; CHECK-NEXT:    [[TMP1:%.*]] = icmp ule i8 [[X]], [[T1]]
104; CHECK-NEXT:    ret i1 [[TMP1]]
105;
106  %t0 = shl i8 -1, %y
107  call void @use8(i8 %t0)
108  %t1 = lshr i8 %t0, %y
109  %x = call i8 @gen8()
110  %t2 = and i8 %t1, %x
111  %ret = icmp eq i8 %x, %t2 ; swapped order
112  ret i1 %ret
113}
114
115define i1 @c2(i8 %y) {
116; CHECK-LABEL: @c2(
117; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
118; CHECK-NEXT:    call void @use8(i8 [[T0]])
119; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
120; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
121; CHECK-NEXT:    [[TMP1:%.*]] = icmp ule i8 [[X]], [[T1]]
122; CHECK-NEXT:    ret i1 [[TMP1]]
123;
124  %t0 = shl i8 -1, %y
125  call void @use8(i8 %t0)
126  %t1 = lshr i8 %t0, %y
127  %x = call i8 @gen8()
128  %t2 = and i8 %x, %t1 ; swapped order
129  %ret = icmp eq i8 %x, %t2 ; swapped order
130  ret i1 %ret
131}
132
133; ============================================================================ ;
134; One-use tests. We don't care about multi-uses here.
135; ============================================================================ ;
136
137define i1 @oneuse0(i8 %x, i8 %y) {
138; CHECK-LABEL: @oneuse0(
139; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
140; CHECK-NEXT:    call void @use8(i8 [[T0]])
141; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
142; CHECK-NEXT:    call void @use8(i8 [[T1]])
143; CHECK-NEXT:    [[TMP1:%.*]] = icmp uge i8 [[T1]], [[X:%.*]]
144; CHECK-NEXT:    ret i1 [[TMP1]]
145;
146  %t0 = shl i8 -1, %y
147  call void @use8(i8 %t0) ; needed anyway
148  %t1 = lshr i8 %t0, %y
149  call void @use8(i8 %t1)
150  %t2 = and i8 %t1, %x
151  %ret = icmp eq i8 %t2, %x
152  ret i1 %ret
153}
154
155define i1 @oneuse1(i8 %x, i8 %y) {
156; CHECK-LABEL: @oneuse1(
157; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
158; CHECK-NEXT:    call void @use8(i8 [[T0]])
159; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
160; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
161; CHECK-NEXT:    call void @use8(i8 [[T2]])
162; CHECK-NEXT:    [[TMP1:%.*]] = icmp uge i8 [[T1]], [[X]]
163; CHECK-NEXT:    ret i1 [[TMP1]]
164;
165  %t0 = shl i8 -1, %y
166  call void @use8(i8 %t0) ; needed anyway
167  %t1 = lshr i8 %t0, %y
168  %t2 = and i8 %t1, %x
169  call void @use8(i8 %t2)
170  %ret = icmp eq i8 %t2, %x
171  ret i1 %ret
172}
173
174define i1 @oneuse2(i8 %x, i8 %y) {
175; CHECK-LABEL: @oneuse2(
176; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
177; CHECK-NEXT:    call void @use8(i8 [[T0]])
178; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
179; CHECK-NEXT:    call void @use8(i8 [[T1]])
180; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
181; CHECK-NEXT:    call void @use8(i8 [[T2]])
182; CHECK-NEXT:    [[TMP1:%.*]] = icmp uge i8 [[T1]], [[X]]
183; CHECK-NEXT:    ret i1 [[TMP1]]
184;
185  %t0 = shl i8 -1, %y
186  call void @use8(i8 %t0)
187  %t1 = lshr i8 %t0, %y
188  call void @use8(i8 %t1)
189  %t2 = and i8 %t1, %x
190  call void @use8(i8 %t2)
191  %ret = icmp eq i8 %t2, %x
192  ret i1 %ret
193}
194
195; ============================================================================ ;
196; Negative tests
197; ============================================================================ ;
198
199define i1 @n0(i8 %x, i8 %y, i8 %notx) {
200; CHECK-LABEL: @n0(
201; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
202; CHECK-NEXT:    call void @use8(i8 [[T0]])
203; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
204; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
205; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[NOTX:%.*]]
206; CHECK-NEXT:    ret i1 [[RET]]
207;
208  %t0 = shl i8 -1, %y
209  call void @use8(i8 %t0)
210  %t1 = lshr i8 %t0, %y
211  %t2 = and i8 %t1, %x
212  %ret = icmp eq i8 %t2, %notx ; not %x
213  ret i1 %ret
214}
215
216define i1 @n1(i8 %x, i8 %y) {
217; CHECK-LABEL: @n1(
218; CHECK-NEXT:    [[T0:%.*]] = shl i8 1, [[Y:%.*]]
219; CHECK-NEXT:    call void @use8(i8 [[T0]])
220; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
221; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
222; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
223; CHECK-NEXT:    ret i1 [[RET]]
224;
225  %t0 = shl i8 1, %y ; not -1
226  call void @use8(i8 %t0)
227  %t1 = lshr i8 %t0, %y
228  %t2 = and i8 %t1, %x
229  %ret = icmp eq i8 %t2, %x
230  ret i1 %ret
231}
232
233define i1 @n2(i8 %x, i8 %y1, i8 %y2) {
234; CHECK-LABEL: @n2(
235; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y1:%.*]]
236; CHECK-NEXT:    call void @use8(i8 [[T0]])
237; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y2:%.*]]
238; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
239; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
240; CHECK-NEXT:    ret i1 [[RET]]
241;
242  %t0 = shl i8 -1, %y1 ; not %y2
243  call void @use8(i8 %t0)
244  %t1 = lshr i8 %t0, %y2 ; not %y1
245  %t2 = and i8 %t1, %x
246  %ret = icmp eq i8 %t2, %x
247  ret i1 %ret
248}
249