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
|
; RUN: opt < %s -rewrite-statepoints-for-gc -S 2>&1 | FileCheck %s
; RUN: opt < %s -passes=rewrite-statepoints-for-gc -S 2>&1 | FileCheck %s
; The rewriting needs to make %obj loop variant by inserting a phi
; of the original value and it's relocation.
declare i64 addrspace(1)* @generate_obj() "gc-leaf-function"
declare void @use_obj(i64 addrspace(1)*) "gc-leaf-function"
define void @def_use_safepoint() gc "statepoint-example" {
; CHECK-LABEL: def_use_safepoint
; CHECK: phi i64 addrspace(1)*
; CHECK-DAG: [ %obj.relocated.casted, %loop ]
; CHECK-DAG: [ %obj, %entry ]
entry:
%obj = call i64 addrspace(1)* @generate_obj()
br label %loop
loop: ; preds = %loop, %entry
call void @use_obj(i64 addrspace(1)* %obj)
call void @do_safepoint() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ]
br label %loop
}
declare void @do_safepoint()
declare void @parse_point(i64 addrspace(1)*)
define i64 addrspace(1)* @test1(i32 %caller, i8 addrspace(1)* %a, i8 addrspace(1)* %b, i32 %unknown) gc "statepoint-example" {
; CHECK-LABEL: test1
entry:
br i1 undef, label %left, label %right
left: ; preds = %entry
; CHECK: left:
; CHECK-NEXT: %a.cast = bitcast i8 addrspace(1)* %a to i64 addrspace(1)*
; CHECK-NEXT: [[CAST_L:%.*]] = bitcast i8 addrspace(1)* %a to i64 addrspace(1)*
; Our safepoint placement pass calls removeUnreachableBlocks, which does a bunch
; of simplifications to branch instructions. This bug is visible only when
; there are multiple branches into the same block from the same predecessor, and
; the following ceremony is to make that artefact survive a call to
; removeUnreachableBlocks. As an example, "br i1 undef, label %merge, label %merge"
; will get simplified to "br label %merge" by removeUnreachableBlocks.
%a.cast = bitcast i8 addrspace(1)* %a to i64 addrspace(1)*
switch i32 %unknown, label %right [
i32 0, label %merge
i32 1, label %merge
i32 5, label %merge
i32 3, label %right
]
right: ; preds = %left, %left, %entry
; CHECK: right:
; CHECK-NEXT: %b.cast = bitcast i8 addrspace(1)* %b to i64 addrspace(1)*
; CHECK-NEXT: [[CAST_R:%.*]] = bitcast i8 addrspace(1)* %b to i64 addrspace(1)*
%b.cast = bitcast i8 addrspace(1)* %b to i64 addrspace(1)*
br label %merge
merge: ; preds = %right, %left, %left, %left
; CHECK: merge:
; CHECK-NEXT: %value.base = phi i64 addrspace(1)* [ [[CAST_L]], %left ], [ [[CAST_L]], %left ], [ [[CAST_L]], %left ], [ [[CAST_R]], %right ], !is_base_value !0
%value = phi i64 addrspace(1)* [ %a.cast, %left ], [ %a.cast, %left ], [ %a.cast, %left ], [ %b.cast, %right ]
call void @parse_point(i64 addrspace(1)* %value) [ "deopt"(i32 0, i32 0, i32 0, i32 0, i32 0) ]
ret i64 addrspace(1)* %value
}
;; The purpose of this test is to ensure that when two live values share a
;; base defining value with inherent conflicts, we end up with a *single*
;; base phi/select per such node. This is testing an optimization, not a
;; fundemental correctness criteria
define void @test2(i1 %cnd, i64 addrspace(1)* %base_obj, i64 addrspace(1)* %base_arg2) gc "statepoint-example" {
; CHECK-LABEL: @test2
entry:
%obj = getelementptr i64, i64 addrspace(1)* %base_obj, i32 1
br label %loop
; CHECK-LABEL: loop
; CHECK: %current.base = phi i64 addrspace(1)*
; CHECK-DAG: [ %base_obj, %entry ]
; Given the two selects are equivelent, so are their base phis - ideally,
; we'd have commoned these, but that's a missed optimization, not correctness.
; CHECK-DAG: [ [[DISCARD:%.*.base.relocated.casted]], %loop ]
; CHECK-NOT: extra.base
; CHECK: next.base = select
; CHECK: next = select
; CHECK: extra2.base = select
; CHECK: extra2 = select
; CHECK: statepoint
;; Both 'next' and 'extra2' are live across the backedge safepoint...
loop: ; preds = %loop, %entry
%current = phi i64 addrspace(1)* [ %obj, %entry ], [ %next, %loop ]
%extra = phi i64 addrspace(1)* [ %obj, %entry ], [ %extra2, %loop ]
%nexta = getelementptr i64, i64 addrspace(1)* %current, i32 1
%next = select i1 %cnd, i64 addrspace(1)* %nexta, i64 addrspace(1)* %base_arg2
%extra2 = select i1 %cnd, i64 addrspace(1)* %nexta, i64 addrspace(1)* %base_arg2
call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ]
br label %loop
}
define i64 addrspace(1)* @test3(i1 %cnd, i64 addrspace(1)* %obj, i64 addrspace(1)* %obj2) gc "statepoint-example" {
; CHECK-LABEL: @test3
entry:
br i1 %cnd, label %merge, label %taken
taken: ; preds = %entry
br label %merge
merge: ; preds = %taken, %entry
; CHECK-LABEL: merge:
; CHECK-NEXT: phi
; CHECK-NEXT: phi
; CHECK-NEXT: gc.statepoint
%bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj2, %taken ]
call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ]
ret i64 addrspace(1)* %bdv
}
define i64 addrspace(1)* @test4(i1 %cnd, i64 addrspace(1)* %obj, i64 addrspace(1)* %obj2) gc "statepoint-example" {
; CHECK-LABEL: @test4
entry:
br i1 %cnd, label %merge, label %taken
taken: ; preds = %entry
br label %merge
merge: ; preds = %taken, %entry
; CHECK-LABEL: merge:
; CHECK-NEXT: phi
; CHECK-NEXT: gc.statepoint
%bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj, %taken ]
call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ]
ret i64 addrspace(1)* %bdv
}
define i64 addrspace(1)* @test5(i1 %cnd, i64 addrspace(1)* %obj, i64 addrspace(1)* %obj2) gc "statepoint-example" {
; CHECK-LABEL: @test5
entry:
br label %merge
merge: ; preds = %merge, %entry
; CHECK-LABEL: merge:
; CHECK-NEXT: phi
; CHECK-NEXT: phi
; CHECK-NEXT: br i1
%bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj2, %merge ]
br i1 %cnd, label %merge, label %next
next: ; preds = %merge
call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ]
ret i64 addrspace(1)* %bdv
}
declare void @foo()
|
