combiner-load-store-indexing.ll
5.51 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
; RUN: llc -mtriple=arm64-apple-ios -global-isel -global-isel-abort=1 -verify-machineinstrs -stop-after=aarch64-prelegalizer-combiner -force-legal-indexing %s -o - | FileCheck %s
; RUN: llc -debugify-and-strip-all-safe -mtriple=arm64-apple-ios -global-isel -global-isel-abort=1 -verify-machineinstrs -stop-after=aarch64-prelegalizer-combiner -force-legal-indexing %s -o - | FileCheck %s
define i8* @test_simple_load_pre(i8* %ptr) {
; CHECK-LABEL: name: test_simple_load_pre
; CHECK: [[BASE:%.*]]:_(p0) = COPY $x0
; CHECK: [[OFFSET:%.*]]:_(s64) = G_CONSTANT i64 42
; CHECK-NOT: G_PTR_ADD
; CHECK: {{%.*}}:_(s8), [[NEXT:%.*]]:_(p0) = G_INDEXED_LOAD [[BASE]], [[OFFSET]](s64), 1
; CHECK: $x0 = COPY [[NEXT]](p0)
%next = getelementptr i8, i8* %ptr, i32 42
load volatile i8, i8* %next
ret i8* %next
}
define i8* @test_unused_load_pre(i8* %ptr) {
; CHECK-LABEL: name: test_unused_load_pre
; CHECK-NOT: G_INDEXED_LOAD
%next = getelementptr i8, i8* %ptr, i32 42
load volatile i8, i8* %next
ret i8* null
}
define void @test_load_multiple_dominated(i8* %ptr, i1 %tst, i1 %tst2) {
; CHECK-LABEL: name: test_load_multiple_dominated
; CHECK: [[BASE:%.*]]:_(p0) = COPY $x0
; CHECK: [[OFFSET:%.*]]:_(s64) = G_CONSTANT i64 42
; CHECK-NOT: G_PTR_ADD
; CHECK: {{%.*}}:_(s8), [[NEXT:%.*]]:_(p0) = G_INDEXED_LOAD [[BASE]], [[OFFSET]](s64), 1
; CHECK: $x0 = COPY [[NEXT]](p0)
%next = getelementptr i8, i8* %ptr, i32 42
br i1 %tst, label %do_load, label %end
do_load:
load volatile i8, i8* %next
br i1 %tst2, label %bb1, label %bb2
bb1:
store volatile i8* %next, i8** undef
ret void
bb2:
call void @bar(i8* %next)
ret void
end:
ret void
}
define i8* @test_simple_store_pre(i8* %ptr) {
; CHECK-LABEL: name: test_simple_store_pre
; CHECK: [[BASE:%.*]]:_(p0) = COPY $x0
; CHECK: [[VAL:%.*]]:_(s8) = G_CONSTANT i8 0
; CHECK: [[OFFSET:%.*]]:_(s64) = G_CONSTANT i64 42
; CHECK-NOT: G_PTR_ADD
; CHECK: [[NEXT:%.*]]:_(p0) = G_INDEXED_STORE [[VAL]](s8), [[BASE]], [[OFFSET]](s64), 1
; CHECK: $x0 = COPY [[NEXT]](p0)
%next = getelementptr i8, i8* %ptr, i32 42
store volatile i8 0, i8* %next
ret i8* %next
}
; The potentially pre-indexed address is used as the value stored. Converting
; would produce the value too late but only by one instruction.
define i64** @test_store_pre_val_loop(i64** %ptr) {
; CHECK-LABEL: name: test_store_pre_val_loop
; CHECK: G_PTR_ADD
; CHECK: G_STORE %
%next = getelementptr i64*, i64** %ptr, i32 42
%next.p0 = bitcast i64** %next to i64*
store volatile i64* %next.p0, i64** %next
ret i64** %next
}
; Potentially pre-indexed address is used between GEP computing it and load.
define i8* @test_load_pre_before(i8* %ptr) {
; CHECK-LABEL: name: test_load_pre_before
; CHECK: G_PTR_ADD
; CHECK: BL @bar
; CHECK: G_LOAD %
%next = getelementptr i8, i8* %ptr, i32 42
call void @bar(i8* %next)
load volatile i8, i8* %next
ret i8* %next
}
; Materializing the base into a writable register (from sp/fp) would be just as
; bad as the original GEP.
define i8* @test_alloca_load_pre() {
; CHECK-LABEL: name: test_alloca_load_pre
; CHECK: G_PTR_ADD
; CHECK: G_LOAD %
%ptr = alloca i8, i32 128
%next = getelementptr i8, i8* %ptr, i32 42
load volatile i8, i8* %next
ret i8* %next
}
; Load does not dominate use of its address. No indexing.
define i8* @test_pre_nodom(i8* %in, i1 %tst) {
; CHECK-LABEL: name: test_pre_nodom
; CHECK: G_PTR_ADD
; CHECK: G_LOAD %
%next = getelementptr i8, i8* %in, i32 16
br i1 %tst, label %do_indexed, label %use_addr
do_indexed:
%val = load i8, i8* %next
store i8 %val, i8* @var
store i8* %next, i8** @varp8
br label %use_addr
use_addr:
ret i8* %next
}
define i8* @test_simple_load_post(i8* %ptr) {
; CHECK-LABEL: name: test_simple_load_post
; CHECK: [[BASE:%.*]]:_(p0) = COPY $x0
; CHECK: [[OFFSET:%.*]]:_(s64) = G_CONSTANT i64 42
; CHECK-NOT: G_PTR_ADD
; CHECK: {{%.*}}:_(s8), [[NEXT:%.*]]:_(p0) = G_INDEXED_LOAD [[BASE]], [[OFFSET]](s64), 0
; CHECK: $x0 = COPY [[NEXT]](p0)
%next = getelementptr i8, i8* %ptr, i32 42
load volatile i8, i8* %ptr
ret i8* %next
}
define i8* @test_simple_load_post_gep_after(i8* %ptr) {
; CHECK-LABEL: name: test_simple_load_post_gep_after
; CHECK: [[BASE:%.*]]:_(p0) = COPY $x0
; CHECK: BL @get_offset
; CHECK: [[OFFSET:%.*]]:_(s64) = COPY $x0
; CHECK: {{%.*}}:_(s8), [[ADDR:%.*]]:_(p0) = G_INDEXED_LOAD [[BASE]], [[OFFSET]](s64), 0
; CHECK: $x0 = COPY [[ADDR]](p0)
%offset = call i64 @get_offset()
load volatile i8, i8* %ptr
%next = getelementptr i8, i8* %ptr, i64 %offset
ret i8* %next
}
define i8* @test_load_post_keep_looking(i8* %ptr) {
; CHECK: name: test_load_post_keep_looking
; CHECK: G_INDEXED_LOAD
%offset = call i64 @get_offset()
load volatile i8, i8* %ptr
%intval = ptrtoint i8* %ptr to i8
store i8 %intval, i8* @var
%next = getelementptr i8, i8* %ptr, i64 %offset
ret i8* %next
}
; Base is frame index. Using indexing would need copy anyway.
define i8* @test_load_post_alloca() {
; CHECK-LABEL: name: test_load_post_alloca
; CHECK: G_PTR_ADD
; CHECK: G_LOAD %
%ptr = alloca i8, i32 128
%next = getelementptr i8, i8* %ptr, i32 42
load volatile i8, i8* %ptr
ret i8* %next
}
; Offset computation does not dominate the load we might be indexing.
define i8* @test_load_post_gep_offset_after(i8* %ptr) {
; CHECK-LABEL: name: test_load_post_gep_offset_after
; CHECK: G_LOAD %
; CHECK: BL @get_offset
; CHECK: G_PTR_ADD
load volatile i8, i8* %ptr
%offset = call i64 @get_offset()
%next = getelementptr i8, i8* %ptr, i64 %offset
ret i8* %next
}
declare void @bar(i8*)
declare i64 @get_offset()
@var = global i8 0
@varp8 = global i8* null