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
|
/*
* Copyright (C) 2024 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 "instruction_simplifier_riscv64.h"
namespace art HIDDEN {
namespace riscv64 {
class InstructionSimplifierRiscv64Visitor final : public HGraphVisitor {
public:
InstructionSimplifierRiscv64Visitor(HGraph* graph, OptimizingCompilerStats* stats)
: HGraphVisitor(graph), stats_(stats) {}
private:
void RecordSimplification() {
MaybeRecordStat(stats_, MethodCompilationStat::kInstructionSimplificationsArch);
}
void VisitBasicBlock(HBasicBlock* block) override {
for (HInstructionIterator it(block->GetInstructions()); !it.Done(); it.Advance()) {
HInstruction* instruction = it.Current();
if (instruction->IsInBlock()) {
instruction->Accept(this);
}
}
}
bool TryReplaceShiftAddWithOneInstruction(HShl* shl, HAdd* add) {
// There is no reason to replace Int32 Shl+Add with ShiftAdd because of
// additional sign-extension required.
if (shl->GetType() != DataType::Type::kInt64) {
return false;
}
if (!shl->GetRight()->IsIntConstant()) {
return false;
}
const int32_t distance = shl->GetRight()->AsIntConstant()->GetValue();
if (distance != 1 && distance != 2 && distance != 3) {
return false;
}
if (!shl->HasOnlyOneNonEnvironmentUse()) {
return false;
}
auto* const add_other_input = add->GetLeft() == shl ? add->GetRight() : add->GetLeft();
auto* const shift_add = new (GetGraph()->GetAllocator())
HRiscv64ShiftAdd(shl->GetLeft(), add_other_input, distance);
DCHECK_EQ(add->GetType(), DataType::Type::kInt64)
<< "Riscv64ShiftAdd replacement should have the same 64 bit type";
add->GetBlock()->ReplaceAndRemoveInstructionWith(add, shift_add);
shl->GetBlock()->RemoveInstruction(shl);
return true;
}
// Replace code looking like
// SHL tmp, a, 1 or 2 or 3
// ADD dst, tmp, b
// with
// Riscv64ShiftAdd dst, a, b
void VisitAdd(HAdd* add) override {
auto* const left = add->GetLeft();
auto* const right = add->GetRight();
if (left->IsShl() && TryReplaceShiftAddWithOneInstruction(left->AsShl(), add)) {
return;
} else if (right->IsShl() && TryReplaceShiftAddWithOneInstruction(right->AsShl(), add)) {
return;
}
}
OptimizingCompilerStats* stats_ = nullptr;
};
bool InstructionSimplifierRiscv64::Run() {
auto visitor = InstructionSimplifierRiscv64Visitor(graph_, stats_);
visitor.VisitReversePostOrder();
return true;
}
} // namespace riscv64
} // namespace art
|