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
| //===-- 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 "MCTargetDesc/BPFMCAsmInfo.h"
#include "TargetInfo/BPFTargetInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
static cl::
opt<bool> DisableMIPeephole("disable-bpf-peephole", cl::Hidden,
cl::desc("Disable machine peepholes for BPF"));
extern "C" void LLVMInitializeBPFTarget() {
// Register the target.
RegisterTargetMachine<BPFTargetMachine> X(getTheBPFleTarget());
RegisterTargetMachine<BPFTargetMachine> Y(getTheBPFbeTarget());
RegisterTargetMachine<BPFTargetMachine> Z(getTheBPFTarget());
PassRegistry &PR = *PassRegistry::getPassRegistry();
initializeBPFAbstractMemberAccessPass(PR);
initializeBPFMIPeepholePass(PR);
initializeBPFMIPeepholeTruncElimPass(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-n32:64-S128";
else
return "e-m:e-p:64:64-i64:64-n32:64-S128";
}
static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
if (!RM.hasValue())
return Reloc::PIC_;
return *RM;
}
BPFTargetMachine::BPFTargetMachine(const Target &T, const Triple &TT,
StringRef CPU, StringRef FS,
const TargetOptions &Options,
Optional<Reloc::Model> RM,
Optional<CodeModel::Model> CM,
CodeGenOpt::Level 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, CPU, 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;
};
}
TargetPassConfig *BPFTargetMachine::createPassConfig(PassManagerBase &PM) {
return new BPFPassConfig(*this, PM);
}
void BPFPassConfig::addIRPasses() {
addPass(createBPFAbstractMemberAccess(&getBPFTargetMachine()));
TargetPassConfig::addIRPasses();
}
// 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());
addPass(createBPFMIPeepholeTruncElimPass());
}
}
void BPFPassConfig::addPreEmitPass() {
addPass(createBPFMIPreEmitCheckingPass());
if (getOptLevel() != CodeGenOpt::None)
if (!DisableMIPeephole)
addPass(createBPFMIPreEmitPeepholePass());
}
|