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1; RUN: opt < %s -sroa -S | FileCheck %s
2
3target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-n8:16:32:64"
4
5define i8 @test1() {
6; We fully promote these to the i24 load or store size, resulting in just masks
7; and other operations that instcombine will fold, but no alloca. Note this is
8; the same as test12 in basictest.ll, but here we assert big-endian byte
9; ordering.
10;
11; CHECK-LABEL: @test1(
12
13entry:
14  %a = alloca [3 x i8]
15  %b = alloca [3 x i8]
16; CHECK-NOT: alloca
17
18  %a0ptr = getelementptr [3 x i8], [3 x i8]* %a, i64 0, i32 0
19  store i8 0, i8* %a0ptr
20  %a1ptr = getelementptr [3 x i8], [3 x i8]* %a, i64 0, i32 1
21  store i8 0, i8* %a1ptr
22  %a2ptr = getelementptr [3 x i8], [3 x i8]* %a, i64 0, i32 2
23  store i8 0, i8* %a2ptr
24  %aiptr = bitcast [3 x i8]* %a to i24*
25  %ai = load i24, i24* %aiptr
26; CHECK-NOT: store
27; CHECK-NOT: load
28; CHECK:      %[[ext2:.*]] = zext i8 0 to i24
29; CHECK-NEXT: %[[mask2:.*]] = and i24 undef, -256
30; CHECK-NEXT: %[[insert2:.*]] = or i24 %[[mask2]], %[[ext2]]
31; CHECK-NEXT: %[[ext1:.*]] = zext i8 0 to i24
32; CHECK-NEXT: %[[shift1:.*]] = shl i24 %[[ext1]], 8
33; CHECK-NEXT: %[[mask1:.*]] = and i24 %[[insert2]], -65281
34; CHECK-NEXT: %[[insert1:.*]] = or i24 %[[mask1]], %[[shift1]]
35; CHECK-NEXT: %[[ext0:.*]] = zext i8 0 to i24
36; CHECK-NEXT: %[[shift0:.*]] = shl i24 %[[ext0]], 16
37; CHECK-NEXT: %[[mask0:.*]] = and i24 %[[insert1]], 65535
38; CHECK-NEXT: %[[insert0:.*]] = or i24 %[[mask0]], %[[shift0]]
39
40  %biptr = bitcast [3 x i8]* %b to i24*
41  store i24 %ai, i24* %biptr
42  %b0ptr = getelementptr [3 x i8], [3 x i8]* %b, i64 0, i32 0
43  %b0 = load i8, i8* %b0ptr
44  %b1ptr = getelementptr [3 x i8], [3 x i8]* %b, i64 0, i32 1
45  %b1 = load i8, i8* %b1ptr
46  %b2ptr = getelementptr [3 x i8], [3 x i8]* %b, i64 0, i32 2
47  %b2 = load i8, i8* %b2ptr
48; CHECK-NOT: store
49; CHECK-NOT: load
50; CHECK:      %[[shift0:.*]] = lshr i24 %[[insert0]], 16
51; CHECK-NEXT: %[[trunc0:.*]] = trunc i24 %[[shift0]] to i8
52; CHECK-NEXT: %[[shift1:.*]] = lshr i24 %[[insert0]], 8
53; CHECK-NEXT: %[[trunc1:.*]] = trunc i24 %[[shift1]] to i8
54; CHECK-NEXT: %[[trunc2:.*]] = trunc i24 %[[insert0]] to i8
55
56  %bsum0 = add i8 %b0, %b1
57  %bsum1 = add i8 %bsum0, %b2
58  ret i8 %bsum1
59; CHECK:      %[[sum0:.*]] = add i8 %[[trunc0]], %[[trunc1]]
60; CHECK-NEXT: %[[sum1:.*]] = add i8 %[[sum0]], %[[trunc2]]
61; CHECK-NEXT: ret i8 %[[sum1]]
62}
63
64define i64 @test2() {
65; Test for various mixed sizes of integer loads and stores all getting
66; promoted.
67;
68; CHECK-LABEL: @test2(
69
70entry:
71  %a = alloca [7 x i8]
72; CHECK-NOT: alloca
73
74  %a0ptr = getelementptr [7 x i8], [7 x i8]* %a, i64 0, i32 0
75  %a1ptr = getelementptr [7 x i8], [7 x i8]* %a, i64 0, i32 1
76  %a2ptr = getelementptr [7 x i8], [7 x i8]* %a, i64 0, i32 2
77  %a3ptr = getelementptr [7 x i8], [7 x i8]* %a, i64 0, i32 3
78
79; CHECK-NOT: store
80; CHECK-NOT: load
81
82  %a0i16ptr = bitcast i8* %a0ptr to i16*
83  store i16 1, i16* %a0i16ptr
84
85  store i8 1, i8* %a2ptr
86; CHECK:      %[[mask1:.*]] = and i40 undef, 4294967295
87; CHECK-NEXT: %[[insert1:.*]] = or i40 %[[mask1]], 4294967296
88
89  %a3i24ptr = bitcast i8* %a3ptr to i24*
90  store i24 1, i24* %a3i24ptr
91; CHECK-NEXT: %[[mask2:.*]] = and i40 %[[insert1]], -4294967041
92; CHECK-NEXT: %[[insert2:.*]] = or i40 %[[mask2]], 256
93
94  %a2i40ptr = bitcast i8* %a2ptr to i40*
95  store i40 1, i40* %a2i40ptr
96; CHECK-NEXT: %[[ext3:.*]] = zext i40 1 to i56
97; CHECK-NEXT: %[[mask3:.*]] = and i56 undef, -1099511627776
98; CHECK-NEXT: %[[insert3:.*]] = or i56 %[[mask3]], %[[ext3]]
99
100; CHECK-NOT: store
101; CHECK-NOT: load
102
103  %aiptr = bitcast [7 x i8]* %a to i56*
104  %ai = load i56, i56* %aiptr
105  %ret = zext i56 %ai to i64
106  ret i64 %ret
107; CHECK-NEXT: %[[ext4:.*]] = zext i16 1 to i56
108; CHECK-NEXT: %[[shift4:.*]] = shl i56 %[[ext4]], 40
109; CHECK-NEXT: %[[mask4:.*]] = and i56 %[[insert3]], 1099511627775
110; CHECK-NEXT: %[[insert4:.*]] = or i56 %[[mask4]], %[[shift4]]
111; CHECK-NEXT: %[[ret:.*]] = zext i56 %[[insert4]] to i64
112; CHECK-NEXT: ret i64 %[[ret]]
113}
114
115define i64 @PR14132(i1 %flag) {
116; CHECK-LABEL: @PR14132(
117; Here we form a PHI-node by promoting the pointer alloca first, and then in
118; order to promote the other two allocas, we speculate the load of the
119; now-phi-node-pointer. In doing so we end up loading a 64-bit value from an i8
120; alloca. While this is a bit dubious, we were asserting on trying to
121; rewrite it. The trick is that the code using the value may carefully take
122; steps to only use the not-undef bits, and so we need to at least loosely
123; support this. This test is particularly interesting because how we handle
124; a load of an i64 from an i8 alloca is dependent on endianness.
125entry:
126  %a = alloca i64, align 8
127  %b = alloca i8, align 8
128  %ptr = alloca i64*, align 8
129; CHECK-NOT: alloca
130
131  %ptr.cast = bitcast i64** %ptr to i8**
132  store i64 0, i64* %a
133  store i8 1, i8* %b
134  store i64* %a, i64** %ptr
135  br i1 %flag, label %if.then, label %if.end
136
137if.then:
138  store i8* %b, i8** %ptr.cast
139  br label %if.end
140; CHECK-NOT: store
141; CHECK: %[[ext:.*]] = zext i8 1 to i64
142; CHECK: %[[shift:.*]] = shl i64 %[[ext]], 56
143
144if.end:
145  %tmp = load i64*, i64** %ptr
146  %result = load i64, i64* %tmp
147; CHECK-NOT: load
148; CHECK: %[[result:.*]] = phi i64 [ %[[shift]], %if.then ], [ 0, %entry ]
149
150  ret i64 %result
151; CHECK-NEXT: ret i64 %[[result]]
152}
153
154declare void @f(i64 %x, i32 %y)
155
156define void @test3() {
157; CHECK-LABEL: @test3(
158;
159; This is a test that specifically exercises the big-endian lowering because it
160; ends up splitting a 64-bit integer into two smaller integers and has a number
161; of tricky aspects (the i24 type) that make that hard. Historically, SROA
162; would miscompile this by either dropping a most significant byte or least
163; significant byte due to shrinking the [4,8) slice to an i24, or by failing to
164; move the bytes around correctly.
165;
166; The magical number 34494054408 is used because it has bits set in various
167; bytes so that it is clear if those bytes fail to be propagated.
168;
169; If you're debugging this, rather than using the direct magical numbers, run
170; the IR through '-sroa -instcombine'. With '-instcombine' these will be
171; constant folded, and if the i64 doesn't round-trip correctly, you've found
172; a bug!
173;
174entry:
175  %a = alloca { i32, i24 }, align 4
176; CHECK-NOT: alloca
177
178  %tmp0 = bitcast { i32, i24 }* %a to i64*
179  store i64 34494054408, i64* %tmp0
180  %tmp1 = load i64, i64* %tmp0, align 4
181  %tmp2 = bitcast { i32, i24 }* %a to i32*
182  %tmp3 = load i32, i32* %tmp2, align 4
183; CHECK: %[[HI_EXT:.*]] = zext i32 134316040 to i64
184; CHECK: %[[HI_INPUT:.*]] = and i64 undef, -4294967296
185; CHECK: %[[HI_MERGE:.*]] = or i64 %[[HI_INPUT]], %[[HI_EXT]]
186; CHECK: %[[LO_EXT:.*]] = zext i32 8 to i64
187; CHECK: %[[LO_SHL:.*]] = shl i64 %[[LO_EXT]], 32
188; CHECK: %[[LO_INPUT:.*]] = and i64 %[[HI_MERGE]], 4294967295
189; CHECK: %[[LO_MERGE:.*]] = or i64 %[[LO_INPUT]], %[[LO_SHL]]
190
191  call void @f(i64 %tmp1, i32 %tmp3)
192; CHECK: call void @f(i64 %[[LO_MERGE]], i32 8)
193  ret void
194; CHECK: ret void
195}
196
197define void @test4() {
198; CHECK-LABEL: @test4
199;
200; Much like @test3, this is specifically testing big-endian management of data.
201; Also similarly, it uses constants with particular bits set to help track
202; whether values are corrupted, and can be easily evaluated by running through
203; -instcombine to see that the i64 round-trips.
204;
205entry:
206  %a = alloca { i32, i24 }, align 4
207  %a2 = alloca i64, align 4
208; CHECK-NOT: alloca
209
210  store i64 34494054408, i64* %a2
211  %tmp0 = bitcast { i32, i24 }* %a to i8*
212  %tmp1 = bitcast i64* %a2 to i8*
213  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %tmp0, i8* %tmp1, i64 8, i32 4, i1 false)
214; CHECK: %[[LO_SHR:.*]] = lshr i64 34494054408, 32
215; CHECK: %[[LO_START:.*]] = trunc i64 %[[LO_SHR]] to i32
216; CHECK: %[[HI_START:.*]] = trunc i64 34494054408 to i32
217
218  %tmp2 = bitcast { i32, i24 }* %a to i64*
219  %tmp3 = load i64, i64* %tmp2, align 4
220  %tmp4 = bitcast { i32, i24 }* %a to i32*
221  %tmp5 = load i32, i32* %tmp4, align 4
222; CHECK: %[[HI_EXT:.*]] = zext i32 %[[HI_START]] to i64
223; CHECK: %[[HI_INPUT:.*]] = and i64 undef, -4294967296
224; CHECK: %[[HI_MERGE:.*]] = or i64 %[[HI_INPUT]], %[[HI_EXT]]
225; CHECK: %[[LO_EXT:.*]] = zext i32 %[[LO_START]] to i64
226; CHECK: %[[LO_SHL:.*]] = shl i64 %[[LO_EXT]], 32
227; CHECK: %[[LO_INPUT:.*]] = and i64 %[[HI_MERGE]], 4294967295
228; CHECK: %[[LO_MERGE:.*]] = or i64 %[[LO_INPUT]], %[[LO_SHL]]
229
230  call void @f(i64 %tmp3, i32 %tmp5)
231; CHECK: call void @f(i64 %[[LO_MERGE]], i32 %[[LO_START]])
232  ret void
233; CHECK: ret void
234}
235
236declare void @llvm.memcpy.p0i8.p0i8.i64(i8*, i8*, i64, i32, i1)
237