xref: /llvm-project/llvm/test/Analysis/ValueTracking/memory-dereferenceable.ll (revision b769758056793472f8638152f30d840856e75b56)
1; RUN: opt -passes=print-memderefs -S < %s -disable-output  -use-dereferenceable-at-point-semantics=false 2>&1 | FileCheck %s --check-prefixes=CHECK,GLOBAL
2; RUN: opt -passes=print-memderefs -S < %s -disable-output  -use-dereferenceable-at-point-semantics 2>&1 | FileCheck %s --check-prefixes=CHECK,POINT
3
4
5; Uses the print-deref (+ analyze to print) pass to run
6; isDereferenceablePointer() on many load instruction operands
7
8target datalayout = "e-i32:32:64"
9
10%TypeOpaque = type opaque
11
12declare zeroext i1 @return_i1()
13
14declare ptr @foo()
15@globalstr = global [6 x i8] c"hello\00"
16@globali32ptr = external global ptr
17
18%struct.A = type { [8 x i8], [5 x i8] }
19@globalstruct = external global %struct.A
20
21@globalptr.align1 = external global i8, align 1
22@globalptr.align16 = external global i8, align 16
23
24; Loads from sret arguments
25; CHECK-LABEL: 'test_sret'
26; CHECK: %sret_gep{{.*}}(aligned)
27; CHECK-NOT: %sret_gep_outside
28define void @test_sret(ptr sret(%struct.A) %result, i1 %arg) {
29  %sret_gep = getelementptr inbounds %struct.A, ptr %result, i64 0, i32 1, i64 2
30  load i8, ptr %sret_gep
31
32  %sret_gep_outside = getelementptr %struct.A, ptr %result, i64 0, i32 1, i64 7
33  load i8, ptr %sret_gep_outside
34  ret void
35}
36
37; CHECK-LABEL: 'test'
38define void @test(ptr addrspace(1) dereferenceable(8) %dparam,
39                  ptr addrspace(1) dereferenceable(32) align 1 %dparam.align1,
40                  ptr addrspace(1) dereferenceable(32) align 16 %dparam.align16)
41    gc "statepoint-example" {
42; CHECK: The following are dereferenceable:
43entry:
44  call void @mayfree()
45
46; GLOBAL: %dparam{{.*}}(unaligned)
47; POINT-NOT: %dparam{{.*}}(unaligned)
48    %load3 = load i32, ptr addrspace(1) %dparam
49
50; GLOBAL: %relocate{{.*}}(unaligned)
51; POINT-NOT: %relocate{{.*}}(unaligned)
52    %tok = tail call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(i1 ()) @return_i1, i32 0, i32 0, i32 0, i32 0) ["gc-live" (ptr addrspace(1) %dparam)]
53    %relocate = call ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %tok, i32 0, i32 0)
54    %load4 = load i32, ptr addrspace(1) %relocate
55
56; CHECK-NOT: %nparam
57    %dpa = call ptr addrspace(1) @func1(ptr addrspace(1) %dparam)
58    %nparam = getelementptr i32, ptr addrspace(1) %dpa, i32 5
59    %load5 = load i32, ptr addrspace(1) %nparam
60
61    ; Load from a non-dereferenceable load
62; CHECK-NOT: %nd_load
63    %nd_load = load ptr, ptr @globali32ptr
64    %load6 = load i32, ptr %nd_load
65
66    ; Load from a dereferenceable load
67; GLOBAL: %d4_load{{.*}}(unaligned)
68; POINT-NOT: %d4_load{{.*}}(unaligned)
69    %d4_load = load ptr, ptr @globali32ptr, !dereferenceable !0
70    %load7 = load i32, ptr %d4_load
71
72    ; Load from an offset not covered by the dereferenceable portion
73; CHECK-NOT: %d2_load
74    %d2_load = load ptr, ptr @globali32ptr, !dereferenceable !1
75    %load8 = load i32, ptr %d2_load
76
77    ; Load from a potentially null pointer with dereferenceable_or_null
78; CHECK-NOT: %d_or_null_load
79    %d_or_null_load = load ptr, ptr @globali32ptr, !dereferenceable_or_null !0
80    %load9 = load i32, ptr %d_or_null_load
81
82    ; Load from a non-null pointer with dereferenceable_or_null
83; GLOBAL: %d_or_null_non_null_load{{.*}}(unaligned)
84; POINT-NOT: %d_or_null_non_null_load{{.*}}(unaligned)
85    %d_or_null_non_null_load = load ptr, ptr @globali32ptr, !nonnull !2, !dereferenceable_or_null !0
86    %load10 = load i32, ptr %d_or_null_non_null_load
87
88    ; Loads from aligned arguments
89; GLOBAL: %dparam.align1{{.*}}(unaligned)
90; POINT-NOT: %dparam.align1{{.*}}(unaligned)
91; POINT-NOT: %dparam.align16{{.*}}(aligned)
92; GLOBAL: %dparam.align16{{.*}}(aligned)
93    %load15 = load i8, ptr addrspace(1) %dparam.align1, align 16
94    %load16 = load i8, ptr addrspace(1) %dparam.align16, align 16
95
96    ; Loads from GEPs
97; GLOBAL: %gep.align1.offset1{{.*}}(unaligned)
98; GLOBAL: %gep.align16.offset1{{.*}}(unaligned)
99; GLOBAL: %gep.align1.offset16{{.*}}(unaligned)
100; GLOBAL: %gep.align16.offset16{{.*}}(aligned)
101; POINT-NOT: %gep.align1.offset1{{.*}}(unaligned)
102; POINT-NOT: %gep.align16.offset1{{.*}}(unaligned)
103; POINT-NOT: %gep.align1.offset16{{.*}}(unaligned)
104; POINT-NOT: %gep.align16.offset16{{.*}}(aligned)
105    %gep.align1.offset1 = getelementptr inbounds i8, ptr addrspace(1) %dparam.align1, i32 1
106    %gep.align16.offset1 = getelementptr inbounds i8, ptr addrspace(1) %dparam.align16, i32 1
107    %gep.align1.offset16 = getelementptr inbounds i8, ptr addrspace(1) %dparam.align1, i32 16
108    %gep.align16.offset16 = getelementptr inbounds i8, ptr addrspace(1) %dparam.align16, i32 16
109    %load19 = load i8, ptr addrspace(1) %gep.align1.offset1, align 16
110    %load20 = load i8, ptr addrspace(1) %gep.align16.offset1, align 16
111    %load21 = load i8, ptr addrspace(1) %gep.align1.offset16, align 16
112    %load22 = load i8, ptr addrspace(1) %gep.align16.offset16, align 16
113
114; CHECK-NOT: %no_deref_return
115; GLOBAL: %deref_return{{.*}}(unaligned)
116; GLOBAL: %deref_and_aligned_return{{.*}}(aligned)
117; POINT-NOT: %deref_return{{.*}}(unaligned)
118; POINT-NOT: %deref_and_aligned_return{{.*}}(aligned)
119    %no_deref_return = call ptr @foo()
120    %deref_return = call dereferenceable(32) ptr @foo()
121    %deref_and_aligned_return = call dereferenceable(32) align 16 ptr @foo()
122    %load23 = load i32, ptr %no_deref_return
123    %load24 = load i32, ptr %deref_return, align 16
124    %load25 = load i32, ptr %deref_and_aligned_return, align 16
125
126    ; Load from a dereferenceable and aligned load
127; GLOBAL: %d4_unaligned_load{{.*}}(unaligned)
128; GLOBAL: %d4_aligned_load{{.*}}(aligned)
129; POINT-NOT: %d4_unaligned_load{{.*}}(unaligned)
130; POINT-NOT: %d4_aligned_load{{.*}}(aligned)
131    %d4_unaligned_load = load ptr, ptr @globali32ptr, !dereferenceable !0
132    %d4_aligned_load = load ptr, ptr @globali32ptr, !dereferenceable !0, !align !{i64 16}
133    %load26 = load i32, ptr %d4_unaligned_load, align 16
134    %load27 = load i32, ptr %d4_aligned_load, align 16
135    ret void
136}
137
138; Loads from aligned allocas
139; CHECK-LABEL: 'alloca_aligned'
140; CHECK: %alloca.align1{{.*}}(unaligned)
141; CHECK: %alloca.align16{{.*}}(aligned)
142define void @alloca_aligned() {
143   %alloca.align1 = alloca i1, align 1
144   %alloca.align16 = alloca i1, align 16
145   call void @mayfree()
146   %load17 = load i1, ptr %alloca.align1, align 16
147   %load18 = load i1, ptr %alloca.align16, align 16
148   ret void
149}
150
151; CHECK-LABEL: 'alloca_basic'
152; CHECK: %alloca{{.*}}(aligned)
153define void @alloca_basic() {
154  %alloca = alloca i1
155  call void @mayfree()
156  %load2 = load i1, ptr %alloca
157  ret void
158}
159
160; Load from empty array alloca
161; CHECK-LABEL: 'alloca_empty'
162; CHECK-NOT: %empty_alloca
163define void @alloca_empty() {
164  %empty_alloca = alloca i8, i64 0
165  call void @mayfree()
166  %empty_load = load i8, ptr %empty_alloca
167  ret void
168}
169
170; Alloca with no explicit alignment is aligned to preferred alignment of
171; the type (specified by datalayout string).
172; CHECK-LABEL: 'alloca_perfalign'
173; CHECK: %alloca.noalign{{.*}}(aligned)
174define void @alloca_perfalign() {
175   %alloca.noalign = alloca i32
176   call void @mayfree()
177   %load28 = load i32, ptr %alloca.noalign, align 8
178   ret void
179}
180
181; CHECK-LABEL: 'global'
182; CHECK: @globalptr.align1{{.*}}(unaligned)
183; CHECK: @globalptr.align16{{.*}}(aligned)
184; CHECK: @globalstr{{.*}}(aligned)
185define void @global() {
186  %load13 = load i8, ptr @globalptr.align1, align 16
187  %load14 = load i8, ptr @globalptr.align16, align 16
188
189  %load1 = load i8, ptr @globalstr
190  ret void
191}
192
193; It's OK to overrun static array size as long as we stay within underlying
194; object size
195; CHECK-LABEL: 'global_allocationsize'
196; CHECK: %within_allocation{{.*}}(aligned)
197; CHECK-NOT: %outside_allocation
198define void @global_allocationsize() {
199  %within_allocation = getelementptr inbounds %struct.A, ptr @globalstruct, i64 0, i32 0, i64 10
200  %load11 = load i8, ptr %within_allocation
201
202  %outside_allocation = getelementptr inbounds %struct.A, ptr @globalstruct, i64 0, i32 1, i64 10
203  %load12 = load i8, ptr %outside_allocation
204  ret void
205}
206
207; Loads from byval arguments
208; CHECK-LABEL: 'byval'
209; CHECK: %i8_byval{{.*}}(aligned)
210; CHECK-NOT: %bad_byval_cast
211; CHECK: %byval_gep{{.*}}(aligned)
212; CHECK: %A_byval{{.*}}(unaligned)
213define void @byval(ptr byval(i8) %i8_byval,
214                   ptr byval(%struct.A) %A_byval) {
215  call void @mayfree()
216  load i8, ptr %i8_byval
217
218  load i32, ptr %i8_byval
219
220  %byval_gep = getelementptr inbounds %struct.A, ptr %A_byval, i64 0, i32 1, i64 2
221  load i8, ptr %byval_gep
222  load i32, ptr %A_byval
223
224  ret void
225}
226
227; CHECK-LABEL: 'f_0'
228; GLOBAL: %ptr = inttoptr i32 %val to ptr, !dereferenceable !0
229; POINT-NOT: %ptr = inttoptr i32 %val to ptr, !dereferenceable !0
230define i32 @f_0(i32 %val) {
231  %ptr = inttoptr i32 %val to ptr, !dereferenceable !0
232  call void @mayfree()
233  %load29 = load i32, ptr %ptr, align 8
234  ret i32 %load29
235}
236
237
238; The most basic case showing the difference between legacy global deref
239; attribute semantics and the new point-in-time semantics.
240; CHECK-LABEL: 'negative'
241; GLOBAL: %p
242; POINT-NOT: %p
243define void @negative(ptr dereferenceable(8) %p) {
244  call void @mayfree()
245  %v = load i32, ptr %p
246  ret void
247}
248
249; CHECK-LABEL: 'infer_func_attrs1'
250; CHECK: %p
251define void @infer_func_attrs1(ptr dereferenceable(8) %p) nofree nosync {
252  call void @mayfree()
253  %v = load i32, ptr %p
254  ret void
255}
256
257; CHECK-LABEL: 'infer_func_attrs2'
258; GLOBAL: %p
259; POINT-NOT: %p
260; FIXME: Can be inferred from attributes
261define void @infer_func_attrs2(ptr dereferenceable(8) %p) readonly {
262  call void @mayfree()
263  %v = load i32, ptr %p
264  ret void
265}
266
267; CHECK-LABEL: 'infer_noalias1'
268; GLOBAL: %p
269; POINT-NOT: %p
270; FIXME: Can be inferred from attributes
271define void @infer_noalias1(ptr dereferenceable(8) noalias nofree %p) {
272  call void @mayfree()
273  %v = load i32, ptr %p
274  ret void
275}
276
277; CHECK-LABEL: 'infer_noalias2'
278; GLOBAL: %p
279; POINT-NOT: %p
280; FIXME: Can be inferred from attributes
281define void @infer_noalias2(ptr dereferenceable(8) noalias readonly %p) nosync {
282  call void @mayfree()
283  %v = load i32, ptr %p
284  ret void
285}
286
287
288; Just check that we don't crash.
289; CHECK-LABEL: 'opaque_type_crasher'
290define void @opaque_type_crasher(ptr dereferenceable(16) %a, i1 %arg) {
291entry:
292  %ptr8 = getelementptr inbounds i8, ptr %a, i32 8
293  br i1 %arg, label %if.then, label %if.end
294
295if.then:
296  %res = load i32, ptr %ptr8, align 4
297  br label %if.end
298
299if.end:
300  ret void
301}
302
303declare token @llvm.experimental.gc.statepoint.p0(i64, i32, ptr, i32, i32, ...)
304declare ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token, i32, i32)
305
306declare ptr addrspace(1) @func1(ptr addrspace(1) returned) nounwind argmemonly
307
308; Can free any object accessible in memory
309declare void @mayfree()
310
311!0 = !{i64 4}
312!1 = !{i64 2}
313!2 = !{}
314