1; RUN: opt < %s -instcombine -S | FileCheck %s
2target 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"
3
4; Instcombine should be able to eliminate all of these ext casts.
5
6declare void @use(i32)
7
8define i64 @test1(i64 %a) {
9  %b = trunc i64 %a to i32
10  %c = and i32 %b, 15
11  %d = zext i32 %c to i64
12  call void @use(i32 %b)
13  ret i64 %d
14; CHECK-LABEL: @test1(
15; CHECK-NOT: ext
16; CHECK: ret
17}
18define i64 @test2(i64 %a) {
19  %b = trunc i64 %a to i32
20  %c = shl i32 %b, 4
21  %q = ashr i32 %c, 4
22  %d = sext i32 %q to i64
23  call void @use(i32 %b)
24  ret i64 %d
25; CHECK-LABEL: @test2(
26; CHECK: shl i64 %a, 36
27; CHECK: %d = ashr exact i64 {{.*}}, 36
28; CHECK: ret i64 %d
29}
30define i64 @test3(i64 %a) {
31  %b = trunc i64 %a to i32
32  %c = and i32 %b, 8
33  %d = zext i32 %c to i64
34  call void @use(i32 %b)
35  ret i64 %d
36; CHECK-LABEL: @test3(
37; CHECK-NOT: ext
38; CHECK: ret
39}
40define i64 @test4(i64 %a) {
41  %b = trunc i64 %a to i32
42  %c = and i32 %b, 8
43  %x = xor i32 %c, 8
44  %d = zext i32 %x to i64
45  call void @use(i32 %b)
46  ret i64 %d
47; CHECK-LABEL: @test4(
48; CHECK: = and i64 %a, 8
49; CHECK: = xor i64 {{.*}}, 8
50; CHECK-NOT: ext
51; CHECK: ret
52}
53
54define i32 @test5(i32 %A) {
55  %B = zext i32 %A to i128
56  %C = lshr i128 %B, 16
57  %D = trunc i128 %C to i32
58  ret i32 %D
59; CHECK-LABEL: @test5(
60; CHECK: %C = lshr i32 %A, 16
61; CHECK: ret i32 %C
62}
63
64define i32 @test6(i64 %A) {
65  %B = zext i64 %A to i128
66  %C = lshr i128 %B, 32
67  %D = trunc i128 %C to i32
68  ret i32 %D
69; CHECK-LABEL: @test6(
70; CHECK: %C = lshr i64 %A, 32
71; CHECK: %D = trunc i64 %C to i32
72; CHECK: ret i32 %D
73}
74
75define i92 @test7(i64 %A) {
76  %B = zext i64 %A to i128
77  %C = lshr i128 %B, 32
78  %D = trunc i128 %C to i92
79  ret i92 %D
80; CHECK-LABEL: @test7(
81; CHECK: %B = zext i64 %A to i92
82; CHECK: %C = lshr i92 %B, 32
83; CHECK: ret i92 %C
84}
85
86define i64 @test8(i32 %A, i32 %B) {
87  %tmp38 = zext i32 %A to i128
88  %tmp32 = zext i32 %B to i128
89  %tmp33 = shl i128 %tmp32, 32
90  %ins35 = or i128 %tmp33, %tmp38
91  %tmp42 = trunc i128 %ins35 to i64
92  ret i64 %tmp42
93; CHECK-LABEL: @test8(
94; CHECK:   %tmp38 = zext i32 %A to i64
95; CHECK:   %tmp32 = zext i32 %B to i64
96; CHECK:   %tmp33 = shl nuw i64 %tmp32, 32
97; CHECK:   %ins35 = or i64 %tmp33, %tmp38
98; CHECK:   ret i64 %ins35
99}
100
101define i8 @test9(i32 %X) {
102  %Y = and i32 %X, 42
103  %Z = trunc i32 %Y to i8
104  ret i8 %Z
105; CHECK-LABEL: @test9(
106; CHECK: trunc
107; CHECK: and
108; CHECK: ret
109}
110
111; rdar://8808586
112define i8 @test10(i32 %X) {
113  %Y = trunc i32 %X to i8
114  %Z = and i8 %Y, 42
115  ret i8 %Z
116; CHECK-LABEL: @test10(
117; CHECK: trunc
118; CHECK: and
119; CHECK: ret
120}
121
122; PR25543
123; https://llvm.org/bugs/show_bug.cgi?id=25543
124; This is an extractelement.
125
126define i32 @trunc_bitcast1(<4 x i32> %v) {
127  %bc = bitcast <4 x i32> %v to i128
128  %shr = lshr i128 %bc, 32
129  %ext = trunc i128 %shr to i32
130  ret i32 %ext
131
132; CHECK-LABEL: @trunc_bitcast1(
133; CHECK-NEXT:  %ext = extractelement <4 x i32> %v, i32 1
134; CHECK-NEXT:  ret i32 %ext
135}
136
137; A bitcast may still be required.
138
139define i32 @trunc_bitcast2(<2 x i64> %v) {
140  %bc = bitcast <2 x i64> %v to i128
141  %shr = lshr i128 %bc, 64
142  %ext = trunc i128 %shr to i32
143  ret i32 %ext
144
145; CHECK-LABEL: @trunc_bitcast2(
146; CHECK-NEXT:  %bc1 = bitcast <2 x i64> %v to <4 x i32>
147; CHECK-NEXT:  %ext = extractelement <4 x i32> %bc1, i32 2
148; CHECK-NEXT:  ret i32 %ext
149}
150
151; The right shift is optional.
152
153define i32 @trunc_bitcast3(<4 x i32> %v) {
154  %bc = bitcast <4 x i32> %v to i128
155  %ext = trunc i128 %bc to i32
156  ret i32 %ext
157
158; CHECK-LABEL: @trunc_bitcast3(
159; CHECK-NEXT:  %ext = extractelement <4 x i32> %v, i32 0
160; CHECK-NEXT:  ret i32 %ext
161}
162
163; CHECK-LABEL: @trunc_shl_infloop(
164; CHECK: %tmp = lshr i64 %arg, 1
165; CHECK: %tmp21 = shl i64 %tmp, 2
166; CHECK: %tmp2 = trunc i64 %tmp21 to i32
167; CHECK: icmp sgt i32 %tmp2, 0
168define void @trunc_shl_infloop(i64 %arg) {
169bb:
170  %tmp = lshr i64 %arg, 1
171  %tmp1 = trunc i64 %tmp to i32
172  %tmp2 = shl i32 %tmp1, 2
173  %tmp3 = icmp sgt i32 %tmp2, 0
174  br i1 %tmp3, label %bb2, label %bb1
175
176bb1:
177  %tmp5 = sub i32 0, %tmp1
178  %tmp6 = sub i32 %tmp5, 1
179  unreachable
180
181bb2:
182  unreachable
183}
184