1 //===-- BPFMCTargetDesc.cpp - BPF Target Descriptions ---------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file provides BPF specific target descriptions.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "MCTargetDesc/BPFMCTargetDesc.h"
14 #include "MCTargetDesc/BPFInstPrinter.h"
15 #include "MCTargetDesc/BPFMCAsmInfo.h"
16 #include "TargetInfo/BPFTargetInfo.h"
17 #include "llvm/MC/MCInstrAnalysis.h"
18 #include "llvm/MC/MCInstrInfo.h"
19 #include "llvm/MC/MCRegisterInfo.h"
20 #include "llvm/MC/MCSubtargetInfo.h"
21 #include "llvm/Support/Host.h"
22 #include "llvm/Support/TargetRegistry.h"
23
24 #define GET_INSTRINFO_MC_DESC
25 #include "BPFGenInstrInfo.inc"
26
27 #define GET_SUBTARGETINFO_MC_DESC
28 #include "BPFGenSubtargetInfo.inc"
29
30 #define GET_REGINFO_MC_DESC
31 #include "BPFGenRegisterInfo.inc"
32
33 using namespace llvm;
34
createBPFMCInstrInfo()35 static MCInstrInfo *createBPFMCInstrInfo() {
36 MCInstrInfo *X = new MCInstrInfo();
37 InitBPFMCInstrInfo(X);
38 return X;
39 }
40
createBPFMCRegisterInfo(const Triple & TT)41 static MCRegisterInfo *createBPFMCRegisterInfo(const Triple &TT) {
42 MCRegisterInfo *X = new MCRegisterInfo();
43 InitBPFMCRegisterInfo(X, BPF::R11 /* RAReg doesn't exist */);
44 return X;
45 }
46
createBPFMCSubtargetInfo(const Triple & TT,StringRef CPU,StringRef FS)47 static MCSubtargetInfo *createBPFMCSubtargetInfo(const Triple &TT,
48 StringRef CPU, StringRef FS) {
49 return createBPFMCSubtargetInfoImpl(TT, CPU, /*TuneCPU*/ CPU, FS);
50 }
51
createBPFMCStreamer(const Triple & T,MCContext & Ctx,std::unique_ptr<MCAsmBackend> && MAB,std::unique_ptr<MCObjectWriter> && OW,std::unique_ptr<MCCodeEmitter> && Emitter,bool RelaxAll)52 static MCStreamer *createBPFMCStreamer(const Triple &T, MCContext &Ctx,
53 std::unique_ptr<MCAsmBackend> &&MAB,
54 std::unique_ptr<MCObjectWriter> &&OW,
55 std::unique_ptr<MCCodeEmitter> &&Emitter,
56 bool RelaxAll) {
57 return createELFStreamer(Ctx, std::move(MAB), std::move(OW), std::move(Emitter),
58 RelaxAll);
59 }
60
createBPFMCInstPrinter(const Triple & T,unsigned SyntaxVariant,const MCAsmInfo & MAI,const MCInstrInfo & MII,const MCRegisterInfo & MRI)61 static MCInstPrinter *createBPFMCInstPrinter(const Triple &T,
62 unsigned SyntaxVariant,
63 const MCAsmInfo &MAI,
64 const MCInstrInfo &MII,
65 const MCRegisterInfo &MRI) {
66 if (SyntaxVariant == 0)
67 return new BPFInstPrinter(MAI, MII, MRI);
68 return nullptr;
69 }
70
71 namespace {
72
73 class BPFMCInstrAnalysis : public MCInstrAnalysis {
74 public:
BPFMCInstrAnalysis(const MCInstrInfo * Info)75 explicit BPFMCInstrAnalysis(const MCInstrInfo *Info)
76 : MCInstrAnalysis(Info) {}
77
evaluateBranch(const MCInst & Inst,uint64_t Addr,uint64_t Size,uint64_t & Target) const78 bool evaluateBranch(const MCInst &Inst, uint64_t Addr, uint64_t Size,
79 uint64_t &Target) const override {
80 // The target is the 3rd operand of cond inst and the 1st of uncond inst.
81 int16_t Imm;
82 if (isConditionalBranch(Inst)) {
83 Imm = Inst.getOperand(2).getImm();
84 } else if (isUnconditionalBranch(Inst))
85 Imm = Inst.getOperand(0).getImm();
86 else
87 return false;
88
89 Target = Addr + Size + Imm * Size;
90 return true;
91 }
92 };
93
94 } // end anonymous namespace
95
createBPFInstrAnalysis(const MCInstrInfo * Info)96 static MCInstrAnalysis *createBPFInstrAnalysis(const MCInstrInfo *Info) {
97 return new BPFMCInstrAnalysis(Info);
98 }
99
LLVMInitializeBPFTargetMC()100 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFTargetMC() {
101 for (Target *T :
102 {&getTheBPFleTarget(), &getTheBPFbeTarget(), &getTheBPFTarget()}) {
103 // Register the MC asm info.
104 RegisterMCAsmInfo<BPFMCAsmInfo> X(*T);
105
106 // Register the MC instruction info.
107 TargetRegistry::RegisterMCInstrInfo(*T, createBPFMCInstrInfo);
108
109 // Register the MC register info.
110 TargetRegistry::RegisterMCRegInfo(*T, createBPFMCRegisterInfo);
111
112 // Register the MC subtarget info.
113 TargetRegistry::RegisterMCSubtargetInfo(*T,
114 createBPFMCSubtargetInfo);
115
116 // Register the object streamer
117 TargetRegistry::RegisterELFStreamer(*T, createBPFMCStreamer);
118
119 // Register the MCInstPrinter.
120 TargetRegistry::RegisterMCInstPrinter(*T, createBPFMCInstPrinter);
121
122 // Register the MC instruction analyzer.
123 TargetRegistry::RegisterMCInstrAnalysis(*T, createBPFInstrAnalysis);
124 }
125
126 // Register the MC code emitter
127 TargetRegistry::RegisterMCCodeEmitter(getTheBPFleTarget(),
128 createBPFMCCodeEmitter);
129 TargetRegistry::RegisterMCCodeEmitter(getTheBPFbeTarget(),
130 createBPFbeMCCodeEmitter);
131
132 // Register the ASM Backend
133 TargetRegistry::RegisterMCAsmBackend(getTheBPFleTarget(),
134 createBPFAsmBackend);
135 TargetRegistry::RegisterMCAsmBackend(getTheBPFbeTarget(),
136 createBPFbeAsmBackend);
137
138 if (sys::IsLittleEndianHost) {
139 TargetRegistry::RegisterMCCodeEmitter(getTheBPFTarget(),
140 createBPFMCCodeEmitter);
141 TargetRegistry::RegisterMCAsmBackend(getTheBPFTarget(),
142 createBPFAsmBackend);
143 } else {
144 TargetRegistry::RegisterMCCodeEmitter(getTheBPFTarget(),
145 createBPFbeMCCodeEmitter);
146 TargetRegistry::RegisterMCAsmBackend(getTheBPFTarget(),
147 createBPFbeAsmBackend);
148 }
149
150 }
151