-
Notifications
You must be signed in to change notification settings - Fork 10.7k
/
BPFTargetMachine.cpp
207 lines (181 loc) · 6.95 KB
/
BPFTargetMachine.cpp
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
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
//===-- BPFTargetMachine.cpp - Define TargetMachine for BPF ---------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Implements the info about BPF target spec.
//
//===----------------------------------------------------------------------===//
#include "BPFTargetMachine.h"
#include "BPF.h"
#include "BPFTargetTransformInfo.h"
#include "MCTargetDesc/BPFMCAsmInfo.h"
#include "TargetInfo/BPFTargetInfo.h"
#include "llvm/CodeGen/GlobalISel/IRTranslator.h"
#include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
#include "llvm/CodeGen/GlobalISel/Legalizer.h"
#include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/IR/PassManager.h"
#include "llvm/InitializePasses.h"
#include "llvm/MC/TargetRegistry.h"
#include "llvm/Passes/PassBuilder.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Scalar/SimplifyCFG.h"
#include "llvm/Transforms/Utils/SimplifyCFGOptions.h"
#include <optional>
using namespace llvm;
static cl::
opt<bool> DisableMIPeephole("disable-bpf-peephole", cl::Hidden,
cl::desc("Disable machine peepholes for BPF"));
extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFTarget() {
// Register the target.
RegisterTargetMachine<BPFTargetMachine> X(getTheBPFleTarget());
RegisterTargetMachine<BPFTargetMachine> Y(getTheBPFbeTarget());
RegisterTargetMachine<BPFTargetMachine> Z(getTheBPFTarget());
PassRegistry &PR = *PassRegistry::getPassRegistry();
initializeGlobalISel(PR);
initializeBPFCheckAndAdjustIRPass(PR);
initializeBPFMIPeepholePass(PR);
initializeBPFDAGToDAGISelPass(PR);
}
// DataLayout: little or big endian
static std::string computeDataLayout(const Triple &TT) {
if (TT.getArch() == Triple::bpfeb)
return "E-m:e-p:64:64-i64:64-i128:128-n32:64-S128";
else
return "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128";
}
static Reloc::Model getEffectiveRelocModel(std::optional<Reloc::Model> RM) {
return RM.value_or(Reloc::PIC_);
}
BPFTargetMachine::BPFTargetMachine(const Target &T, const Triple &TT,
StringRef CPU, StringRef FS,
const TargetOptions &Options,
std::optional<Reloc::Model> RM,
std::optional<CodeModel::Model> CM,
CodeGenOptLevel OL, bool JIT)
: LLVMTargetMachine(T, computeDataLayout(TT), TT, CPU, FS, Options,
getEffectiveRelocModel(RM),
getEffectiveCodeModel(CM, CodeModel::Small), OL),
TLOF(std::make_unique<TargetLoweringObjectFileELF>()),
Subtarget(TT, std::string(CPU), std::string(FS), *this) {
initAsmInfo();
BPFMCAsmInfo *MAI =
static_cast<BPFMCAsmInfo *>(const_cast<MCAsmInfo *>(AsmInfo.get()));
MAI->setDwarfUsesRelocationsAcrossSections(!Subtarget.getUseDwarfRIS());
}
namespace {
// BPF Code Generator Pass Configuration Options.
class BPFPassConfig : public TargetPassConfig {
public:
BPFPassConfig(BPFTargetMachine &TM, PassManagerBase &PM)
: TargetPassConfig(TM, PM) {}
BPFTargetMachine &getBPFTargetMachine() const {
return getTM<BPFTargetMachine>();
}
void addIRPasses() override;
bool addInstSelector() override;
void addMachineSSAOptimization() override;
void addPreEmitPass() override;
bool addIRTranslator() override;
bool addLegalizeMachineIR() override;
bool addRegBankSelect() override;
bool addGlobalInstructionSelect() override;
};
}
TargetPassConfig *BPFTargetMachine::createPassConfig(PassManagerBase &PM) {
return new BPFPassConfig(*this, PM);
}
void BPFTargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
PB.registerPipelineParsingCallback(
[](StringRef PassName, FunctionPassManager &FPM,
ArrayRef<PassBuilder::PipelineElement>) {
if (PassName == "bpf-ir-peephole") {
FPM.addPass(BPFIRPeepholePass());
return true;
}
if (PassName == "bpf-preserve-static-offset") {
FPM.addPass(BPFPreserveStaticOffsetPass(false));
return true;
}
return false;
});
PB.registerPipelineStartEPCallback(
[=](ModulePassManager &MPM, OptimizationLevel) {
FunctionPassManager FPM;
FPM.addPass(BPFPreserveStaticOffsetPass(true));
FPM.addPass(BPFAbstractMemberAccessPass(this));
FPM.addPass(BPFPreserveDITypePass());
FPM.addPass(BPFIRPeepholePass());
MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
});
PB.registerPeepholeEPCallback([=](FunctionPassManager &FPM,
OptimizationLevel Level) {
FPM.addPass(SimplifyCFGPass(SimplifyCFGOptions().hoistCommonInsts(true)));
});
PB.registerScalarOptimizerLateEPCallback(
[=](FunctionPassManager &FPM, OptimizationLevel Level) {
// Run this after loop unrolling but before
// SimplifyCFGPass(... .sinkCommonInsts(true))
FPM.addPass(BPFPreserveStaticOffsetPass(false));
});
PB.registerPipelineEarlySimplificationEPCallback(
[=](ModulePassManager &MPM, OptimizationLevel) {
MPM.addPass(BPFAdjustOptPass());
});
}
void BPFPassConfig::addIRPasses() {
addPass(createBPFCheckAndAdjustIR());
TargetPassConfig::addIRPasses();
}
TargetTransformInfo
BPFTargetMachine::getTargetTransformInfo(const Function &F) const {
return TargetTransformInfo(BPFTTIImpl(this, F));
}
// Install an instruction selector pass using
// the ISelDag to gen BPF code.
bool BPFPassConfig::addInstSelector() {
addPass(createBPFISelDag(getBPFTargetMachine()));
return false;
}
void BPFPassConfig::addMachineSSAOptimization() {
addPass(createBPFMISimplifyPatchablePass());
// The default implementation must be called first as we want eBPF
// Peephole ran at last.
TargetPassConfig::addMachineSSAOptimization();
const BPFSubtarget *Subtarget = getBPFTargetMachine().getSubtargetImpl();
if (!DisableMIPeephole) {
if (Subtarget->getHasAlu32())
addPass(createBPFMIPeepholePass());
}
}
void BPFPassConfig::addPreEmitPass() {
addPass(createBPFMIPreEmitCheckingPass());
if (getOptLevel() != CodeGenOptLevel::None)
if (!DisableMIPeephole)
addPass(createBPFMIPreEmitPeepholePass());
}
bool BPFPassConfig::addIRTranslator() {
addPass(new IRTranslator());
return false;
}
bool BPFPassConfig::addLegalizeMachineIR() {
addPass(new Legalizer());
return false;
}
bool BPFPassConfig::addRegBankSelect() {
addPass(new RegBankSelect());
return false;
}
bool BPFPassConfig::addGlobalInstructionSelect() {
addPass(new InstructionSelect(getOptLevel()));
return false;
}