xref: /llvm-project/llvm/test/Transforms/InstCombine/overflow-mul.ll (revision 38fffa630ee80163dc65e759392ad29798905679)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -S -passes=instcombine < %s | FileCheck %s
3
4; The last test needs this weird datalayout.
5target datalayout = "i32:8:8"
6; Without it, InstCombine will align the pointed on 4 Bytes
7; The KnownBitsZero that result from the alignment allows to
8; turn:
9;    and i32 %mul, 255
10; to:
11;    and i32 %mul, 252
12; The mask is no longer in the form 2^n-1  and this prevents the transformation.
13
14declare void @use.i64(i64)
15
16; return mul(zext x, zext y) > MAX
17define i32 @pr4917_1(i32 %x, i32 %y) nounwind {
18; CHECK-LABEL: @pr4917_1(
19; CHECK-NEXT:  entry:
20; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
21; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
22; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
23; CHECK-NEXT:    ret i32 [[RETVAL]]
24;
25entry:
26  %l = zext i32 %x to i64
27  %r = zext i32 %y to i64
28  %mul64 = mul i64 %l, %r
29  %overflow = icmp ugt i64 %mul64, 4294967295
30  %retval = zext i1 %overflow to i32
31  ret i32 %retval
32}
33
34; return mul(zext x, zext y) >= MAX+1
35define i32 @pr4917_1a(i32 %x, i32 %y) nounwind {
36; CHECK-LABEL: @pr4917_1a(
37; CHECK-NEXT:  entry:
38; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
39; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
40; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
41; CHECK-NEXT:    ret i32 [[RETVAL]]
42;
43entry:
44  %l = zext i32 %x to i64
45  %r = zext i32 %y to i64
46  %mul64 = mul i64 %l, %r
47  %overflow = icmp uge i64 %mul64, 4294967296
48  %retval = zext i1 %overflow to i32
49  ret i32 %retval
50}
51
52; mul(zext x, zext y) > MAX
53; mul(x, y) is used
54define i32 @pr4917_2(i32 %x, i32 %y) nounwind {
55; CHECK-LABEL: @pr4917_2(
56; CHECK-NEXT:  entry:
57; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
58; CHECK-NEXT:    [[UMUL_VALUE:%.*]] = extractvalue { i32, i1 } [[UMUL]], 0
59; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
60; CHECK-NEXT:    [[RETVAL:%.*]] = select i1 [[OVERFLOW]], i32 [[UMUL_VALUE]], i32 111
61; CHECK-NEXT:    ret i32 [[RETVAL]]
62;
63entry:
64  %l = zext i32 %x to i64
65  %r = zext i32 %y to i64
66  %mul64 = mul i64 %l, %r
67  %overflow = icmp ugt i64 %mul64, 4294967295
68  %mul32 = trunc i64 %mul64 to i32
69  %retval = select i1 %overflow, i32 %mul32, i32 111
70  ret i32 %retval
71}
72
73; return mul(zext x, zext y) > MAX
74; mul is used in non-truncate
75define i64 @pr4917_3(i32 %x, i32 %y) nounwind {
76; CHECK-LABEL: @pr4917_3(
77; CHECK-NEXT:  entry:
78; CHECK-NEXT:    [[L:%.*]] = zext i32 [[X:%.*]] to i64
79; CHECK-NEXT:    [[R:%.*]] = zext i32 [[Y:%.*]] to i64
80; CHECK-NEXT:    [[MUL64:%.*]] = mul nuw i64 [[L]], [[R]]
81; CHECK-NEXT:    [[OVERFLOW:%.*]] = icmp ugt i64 [[MUL64]], 4294967295
82; CHECK-NEXT:    [[RETVAL:%.*]] = select i1 [[OVERFLOW]], i64 [[MUL64]], i64 111
83; CHECK-NEXT:    ret i64 [[RETVAL]]
84;
85entry:
86  %l = zext i32 %x to i64
87  %r = zext i32 %y to i64
88  %mul64 = mul i64 %l, %r
89  %overflow = icmp ugt i64 %mul64, 4294967295
90  %retval = select i1 %overflow, i64 %mul64, i64 111
91  ret i64 %retval
92}
93
94; return mul(zext x, zext y) <= MAX
95define i32 @pr4917_4(i32 %x, i32 %y) nounwind {
96; CHECK-LABEL: @pr4917_4(
97; CHECK-NEXT:  entry:
98; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
99; CHECK-NEXT:    [[TMP0:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
100; CHECK-NEXT:    [[OVERFLOW:%.*]] = xor i1 [[TMP0]], true
101; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
102; CHECK-NEXT:    ret i32 [[RETVAL]]
103;
104entry:
105  %l = zext i32 %x to i64
106  %r = zext i32 %y to i64
107  %mul64 = mul i64 %l, %r
108  %overflow = icmp ule i64 %mul64, 4294967295
109  %retval = zext i1 %overflow to i32
110  ret i32 %retval
111}
112
113; return mul(zext x, zext y) < MAX+1
114define i32 @pr4917_4a(i32 %x, i32 %y) nounwind {
115; CHECK-LABEL: @pr4917_4a(
116; CHECK-NEXT:  entry:
117; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
118; CHECK-NEXT:    [[TMP0:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
119; CHECK-NEXT:    [[OVERFLOW:%.*]] = xor i1 [[TMP0]], true
120; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
121; CHECK-NEXT:    ret i32 [[RETVAL]]
122;
123entry:
124  %l = zext i32 %x to i64
125  %r = zext i32 %y to i64
126  %mul64 = mul i64 %l, %r
127  %overflow = icmp ult i64 %mul64, 4294967296
128  %retval = zext i1 %overflow to i32
129  ret i32 %retval
130}
131
132; operands of mul are of different size
133define i32 @pr4917_5(i32 %x, i8 %y) nounwind {
134; CHECK-LABEL: @pr4917_5(
135; CHECK-NEXT:  entry:
136; CHECK-NEXT:    [[TMP0:%.*]] = zext i8 [[Y:%.*]] to i32
137; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[TMP0]])
138; CHECK-NEXT:    [[UMUL_VALUE:%.*]] = extractvalue { i32, i1 } [[UMUL]], 0
139; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
140; CHECK-NEXT:    [[RETVAL:%.*]] = select i1 [[OVERFLOW]], i32 [[UMUL_VALUE]], i32 111
141; CHECK-NEXT:    ret i32 [[RETVAL]]
142;
143entry:
144  %l = zext i32 %x to i64
145  %r = zext i8 %y to i64
146  %mul64 = mul i64 %l, %r
147  %overflow = icmp ugt i64 %mul64, 4294967295
148  %mul32 = trunc i64 %mul64 to i32
149  %retval = select i1 %overflow, i32 %mul32, i32 111
150  ret i32 %retval
151}
152
153; mul(zext x, zext y) != zext trunc mul
154define i32 @pr4918_1(i32 %x, i32 %y) nounwind {
155; CHECK-LABEL: @pr4918_1(
156; CHECK-NEXT:  entry:
157; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
158; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
159; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
160; CHECK-NEXT:    ret i32 [[RETVAL]]
161;
162entry:
163  %l = zext i32 %x to i64
164  %r = zext i32 %y to i64
165  %mul64 = mul i64 %l, %r
166  %part32 = trunc i64 %mul64 to i32
167  %part64 = zext i32 %part32 to i64
168  %overflow = icmp ne i64 %mul64, %part64
169  %retval = zext i1 %overflow to i32
170  ret i32 %retval
171}
172
173; mul(zext x, zext y) == zext trunc mul
174define i32 @pr4918_2(i32 %x, i32 %y) nounwind {
175; CHECK-LABEL: @pr4918_2(
176; CHECK-NEXT:  entry:
177; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
178; CHECK-NEXT:    [[TMP0:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
179; CHECK-NEXT:    [[OVERFLOW:%.*]] = xor i1 [[TMP0]], true
180; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
181; CHECK-NEXT:    ret i32 [[RETVAL]]
182;
183entry:
184  %l = zext i32 %x to i64
185  %r = zext i32 %y to i64
186  %mul64 = mul i64 %l, %r
187  %part32 = trunc i64 %mul64 to i32
188  %part64 = zext i32 %part32 to i64
189  %overflow = icmp eq i64 %mul64, %part64
190  %retval = zext i1 %overflow to i32
191  ret i32 %retval
192}
193
194; zext trunc mul != mul(zext x, zext y)
195define i32 @pr4918_3(i32 %x, i32 %y) nounwind {
196; CHECK-LABEL: @pr4918_3(
197; CHECK-NEXT:  entry:
198; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
199; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
200; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
201; CHECK-NEXT:    ret i32 [[RETVAL]]
202;
203entry:
204  %l = zext i32 %x to i64
205  %r = zext i32 %y to i64
206  %mul64 = mul i64 %l, %r
207  %part32 = trunc i64 %mul64 to i32
208  %part64 = zext i32 %part32 to i64
209  %overflow = icmp ne i64 %part64, %mul64
210  %retval = zext i1 %overflow to i32
211  ret i32 %retval
212}
213
214define <4 x i32> @pr20113(<4 x i16> %a, <4 x i16> %b) {
215; CHECK-LABEL: @pr20113(
216; CHECK-NEXT:    [[VMOVL_I_I726:%.*]] = zext <4 x i16> [[A:%.*]] to <4 x i32>
217; CHECK-NEXT:    [[VMOVL_I_I712:%.*]] = zext <4 x i16> [[B:%.*]] to <4 x i32>
218; CHECK-NEXT:    [[MUL_I703:%.*]] = mul nuw <4 x i32> [[VMOVL_I_I712]], [[VMOVL_I_I726]]
219; CHECK-NEXT:    [[TMP:%.*]] = icmp sgt <4 x i32> [[MUL_I703]], splat (i32 -1)
220; CHECK-NEXT:    [[VCGEZ_I:%.*]] = sext <4 x i1> [[TMP]] to <4 x i32>
221; CHECK-NEXT:    ret <4 x i32> [[VCGEZ_I]]
222;
223  %vmovl.i.i726 = zext <4 x i16> %a to <4 x i32>
224  %vmovl.i.i712 = zext <4 x i16> %b to <4 x i32>
225  %mul.i703 = mul <4 x i32> %vmovl.i.i712, %vmovl.i.i726
226  %tmp = icmp sge <4 x i32> %mul.i703, zeroinitializer
227  %vcgez.i = sext <4 x i1> %tmp to <4 x i32>
228  ret <4 x i32> %vcgez.i
229}
230
231
232@pr21445_data = external global i32
233define i1 @pr21445(i8 %a) {
234; CHECK-LABEL: @pr21445(
235; CHECK-NEXT:    [[UMUL:%.*]] = call { i8, i1 } @llvm.umul.with.overflow.i8(i8 [[A:%.*]], i8 ptrtoint (ptr @pr21445_data to i8))
236; CHECK-NEXT:    [[CMP:%.*]] = extractvalue { i8, i1 } [[UMUL]], 1
237; CHECK-NEXT:    ret i1 [[CMP]]
238;
239  %ext = zext i8 %a to i32
240  %ext2 = zext i8 ptrtoint (ptr @pr21445_data to i8) to i32
241  %mul = mul i32 %ext, %ext2
242  %and = and i32 %mul, 255
243  %cmp = icmp ne i32 %mul, %and
244  ret i1 %cmp
245}
246
247; Negative test: mul(zext x, zext y) may overflow.
248define i32 @mul_may_overflow(i32 %x, i32 %y) {
249; CHECK-LABEL: @mul_may_overflow(
250; CHECK-NEXT:  entry:
251; CHECK-NEXT:    [[L:%.*]] = zext i32 [[X:%.*]] to i34
252; CHECK-NEXT:    [[R:%.*]] = zext i32 [[Y:%.*]] to i34
253; CHECK-NEXT:    [[MUL34:%.*]] = mul i34 [[L]], [[R]]
254; CHECK-NEXT:    [[OVERFLOW:%.*]] = icmp ult i34 [[MUL34]], 4294967296
255; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
256; CHECK-NEXT:    ret i32 [[RETVAL]]
257;
258entry:
259  %l = zext i32 %x to i34
260  %r = zext i32 %y to i34
261  %mul34 = mul i34 %l, %r
262  %overflow = icmp ule i34 %mul34, 4294967295
263  %retval = zext i1 %overflow to i32
264  ret i32 %retval
265}
266
267define i32 @mul_known_nuw(i32 %x, i32 %y) {
268; CHECK-LABEL: @mul_known_nuw(
269; CHECK-NEXT:  entry:
270; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
271; CHECK-NEXT:    [[TMP0:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
272; CHECK-NEXT:    [[OVERFLOW:%.*]] = xor i1 [[TMP0]], true
273; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
274; CHECK-NEXT:    ret i32 [[RETVAL]]
275;
276entry:
277  %l = zext i32 %x to i34
278  %r = zext i32 %y to i34
279  %mul34 = mul nuw i34 %l, %r
280  %overflow = icmp ule i34 %mul34, 4294967295
281  %retval = zext i1 %overflow to i32
282  ret i32 %retval
283}
284
285define i32 @extra_and_use(i32 %x, i32 %y) {
286; CHECK-LABEL: @extra_and_use(
287; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
288; CHECK-NEXT:    [[UMUL_VALUE:%.*]] = extractvalue { i32, i1 } [[UMUL]], 0
289; CHECK-NEXT:    [[AND:%.*]] = zext i32 [[UMUL_VALUE]] to i64
290; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
291; CHECK-NEXT:    call void @use.i64(i64 [[AND]])
292; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
293; CHECK-NEXT:    ret i32 [[RETVAL]]
294;
295  %l = zext i32 %x to i64
296  %r = zext i32 %y to i64
297  %mul64 = mul i64 %l, %r
298  %overflow = icmp ugt i64 %mul64, 4294967295
299  %and = and i64 %mul64, u0xffffffff
300  call void @use.i64(i64 %and)
301  %retval = zext i1 %overflow to i32
302  ret i32 %retval
303}
304
305define i32 @extra_and_use_small_mask(i32 %x, i32 %y) {
306; CHECK-LABEL: @extra_and_use_small_mask(
307; CHECK-NEXT:    [[UMUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
308; CHECK-NEXT:    [[UMUL_VALUE:%.*]] = extractvalue { i32, i1 } [[UMUL]], 0
309; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[UMUL_VALUE]], 268435455
310; CHECK-NEXT:    [[AND:%.*]] = zext nneg i32 [[TMP1]] to i64
311; CHECK-NEXT:    [[OVERFLOW:%.*]] = extractvalue { i32, i1 } [[UMUL]], 1
312; CHECK-NEXT:    call void @use.i64(i64 [[AND]])
313; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
314; CHECK-NEXT:    ret i32 [[RETVAL]]
315;
316  %l = zext i32 %x to i64
317  %r = zext i32 %y to i64
318  %mul64 = mul i64 %l, %r
319  %overflow = icmp ugt i64 %mul64, 4294967295
320  %and = and i64 %mul64, u0xfffffff
321  call void @use.i64(i64 %and)
322  %retval = zext i1 %overflow to i32
323  ret i32 %retval
324}
325
326define i32 @extra_and_use_mask_too_large(i32 %x, i32 %y) {
327; CHECK-LABEL: @extra_and_use_mask_too_large(
328; CHECK-NEXT:    [[L:%.*]] = zext i32 [[X:%.*]] to i64
329; CHECK-NEXT:    [[R:%.*]] = zext i32 [[Y:%.*]] to i64
330; CHECK-NEXT:    [[MUL64:%.*]] = mul nuw i64 [[L]], [[R]]
331; CHECK-NEXT:    [[OVERFLOW:%.*]] = icmp ugt i64 [[MUL64]], 4294967295
332; CHECK-NEXT:    [[AND:%.*]] = and i64 [[MUL64]], 68719476735
333; CHECK-NEXT:    call void @use.i64(i64 [[AND]])
334; CHECK-NEXT:    [[RETVAL:%.*]] = zext i1 [[OVERFLOW]] to i32
335; CHECK-NEXT:    ret i32 [[RETVAL]]
336;
337  %l = zext i32 %x to i64
338  %r = zext i32 %y to i64
339  %mul64 = mul i64 %l, %r
340  %overflow = icmp ugt i64 %mul64, 4294967295
341  %and = and i64 %mul64, u0xfffffffff
342  call void @use.i64(i64 %and)
343  %retval = zext i1 %overflow to i32
344  ret i32 %retval
345}
346