blob: 78d11857c3fcf9bb18cc5969069a041584c4ba26 (
plain)
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
|
/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "prepare_for_register_allocation.h"
namespace art {
void PrepareForRegisterAllocation::Run() {
// Order does not matter.
for (HReversePostOrderIterator it(*GetGraph()); !it.Done(); it.Advance()) {
HBasicBlock* block = it.Current();
// No need to visit the phis.
for (HInstructionIterator inst_it(block->GetInstructions()); !inst_it.Done();
inst_it.Advance()) {
inst_it.Current()->Accept(this);
}
}
}
void PrepareForRegisterAllocation::VisitNullCheck(HNullCheck* check) {
check->ReplaceWith(check->InputAt(0));
}
void PrepareForRegisterAllocation::VisitDivZeroCheck(HDivZeroCheck* check) {
check->ReplaceWith(check->InputAt(0));
}
void PrepareForRegisterAllocation::VisitBoundsCheck(HBoundsCheck* check) {
check->ReplaceWith(check->InputAt(0));
}
void PrepareForRegisterAllocation::VisitBoundType(HBoundType* bound_type) {
bound_type->ReplaceWith(bound_type->InputAt(0));
bound_type->GetBlock()->RemoveInstruction(bound_type);
}
void PrepareForRegisterAllocation::VisitClinitCheck(HClinitCheck* check) {
HLoadClass* cls = check->GetLoadClass();
check->ReplaceWith(cls);
if (check->GetPrevious() == cls) {
// Pass the initialization duty to the `HLoadClass` instruction,
// and remove the instruction from the graph.
cls->SetMustGenerateClinitCheck();
check->GetBlock()->RemoveInstruction(check);
}
}
void PrepareForRegisterAllocation::VisitCondition(HCondition* condition) {
bool needs_materialization = false;
if (!condition->GetUses().HasOnlyOneUse() || !condition->GetEnvUses().IsEmpty()) {
needs_materialization = true;
} else {
HInstruction* user = condition->GetUses().GetFirst()->GetUser();
if (!user->IsIf() && !user->IsDeoptimize()) {
needs_materialization = true;
} else {
// TODO: if there is no intervening instructions with side-effect between this condition
// and the If instruction, we should move the condition just before the If.
if (condition->GetNext() != user) {
needs_materialization = true;
}
}
}
if (!needs_materialization) {
condition->ClearNeedsMaterialization();
}
}
void PrepareForRegisterAllocation::VisitInvokeStaticOrDirect(HInvokeStaticOrDirect* invoke) {
if (invoke->IsStaticWithExplicitClinitCheck()) {
size_t last_input_index = invoke->InputCount() - 1;
HInstruction* last_input = invoke->InputAt(last_input_index);
DCHECK(last_input->IsLoadClass()) << last_input->DebugName();
// Remove a load class instruction as last input of a static
// invoke, which has been added (along with a clinit check,
// removed by PrepareForRegisterAllocation::VisitClinitCheck
// previously) by the graph builder during the creation of the
// static invoke instruction, but is no longer required at this
// stage (i.e., after inlining has been performed).
invoke->RemoveLoadClassAsLastInput();
// If the load class instruction is no longer used, remove it from
// the graph.
if (!last_input->HasUses()) {
last_input->GetBlock()->RemoveInstruction(last_input);
}
}
}
} // namespace art
|
