1//===-- PPCMCTargetDesc.cpp - PowerPC Target Descriptions -----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file provides PowerPC specific target descriptions.
11//
12//===----------------------------------------------------------------------===//
13
14#include "PPCMCTargetDesc.h"
15#include "InstPrinter/PPCInstPrinter.h"
16#include "PPCMCAsmInfo.h"
17#include "PPCTargetStreamer.h"
18#include "llvm/MC/MCCodeGenInfo.h"
19#include "llvm/MC/MCContext.h"
20#include "llvm/MC/MCELFStreamer.h"
21#include "llvm/MC/MCExpr.h"
22#include "llvm/MC/MCInstrInfo.h"
23#include "llvm/MC/MCRegisterInfo.h"
24#include "llvm/MC/MCStreamer.h"
25#include "llvm/MC/MCSubtargetInfo.h"
26#include "llvm/MC/MCSymbolELF.h"
27#include "llvm/MC/MachineLocation.h"
28#include "llvm/Support/ELF.h"
29#include "llvm/Support/ErrorHandling.h"
30#include "llvm/Support/FormattedStream.h"
31#include "llvm/Support/TargetRegistry.h"
32
33using namespace llvm;
34
35#define GET_INSTRINFO_MC_DESC
36#include "PPCGenInstrInfo.inc"
37
38#define GET_SUBTARGETINFO_MC_DESC
39#include "PPCGenSubtargetInfo.inc"
40
41#define GET_REGINFO_MC_DESC
42#include "PPCGenRegisterInfo.inc"
43
44// Pin the vtable to this file.
45PPCTargetStreamer::~PPCTargetStreamer() {}
46PPCTargetStreamer::PPCTargetStreamer(MCStreamer &S) : MCTargetStreamer(S) {}
47
48static MCInstrInfo *createPPCMCInstrInfo() {
49  MCInstrInfo *X = new MCInstrInfo();
50  InitPPCMCInstrInfo(X);
51  return X;
52}
53
54static MCRegisterInfo *createPPCMCRegisterInfo(const Triple &TT) {
55  bool isPPC64 =
56      (TT.getArch() == Triple::ppc64 || TT.getArch() == Triple::ppc64le);
57  unsigned Flavour = isPPC64 ? 0 : 1;
58  unsigned RA = isPPC64 ? PPC::LR8 : PPC::LR;
59
60  MCRegisterInfo *X = new MCRegisterInfo();
61  InitPPCMCRegisterInfo(X, RA, Flavour, Flavour);
62  return X;
63}
64
65static MCSubtargetInfo *createPPCMCSubtargetInfo(const Triple &TT,
66                                                 StringRef CPU, StringRef FS) {
67  return createPPCMCSubtargetInfoImpl(TT, CPU, FS);
68}
69
70static MCAsmInfo *createPPCMCAsmInfo(const MCRegisterInfo &MRI,
71                                     const Triple &TheTriple) {
72  bool isPPC64 = (TheTriple.getArch() == Triple::ppc64 ||
73                  TheTriple.getArch() == Triple::ppc64le);
74
75  MCAsmInfo *MAI;
76  if (TheTriple.isOSDarwin())
77    MAI = new PPCMCAsmInfoDarwin(isPPC64, TheTriple);
78  else
79    MAI = new PPCELFMCAsmInfo(isPPC64, TheTriple);
80
81  // Initial state of the frame pointer is R1.
82  unsigned Reg = isPPC64 ? PPC::X1 : PPC::R1;
83  MCCFIInstruction Inst =
84      MCCFIInstruction::createDefCfa(nullptr, MRI.getDwarfRegNum(Reg, true), 0);
85  MAI->addInitialFrameState(Inst);
86
87  return MAI;
88}
89
90static MCCodeGenInfo *createPPCMCCodeGenInfo(const Triple &TT, Reloc::Model RM,
91                                             CodeModel::Model CM,
92                                             CodeGenOpt::Level OL) {
93  MCCodeGenInfo *X = new MCCodeGenInfo();
94
95  if (RM == Reloc::Default) {
96    if (TT.isOSDarwin())
97      RM = Reloc::DynamicNoPIC;
98    else
99      RM = Reloc::Static;
100  }
101  if (CM == CodeModel::Default) {
102    if (!TT.isOSDarwin() &&
103        (TT.getArch() == Triple::ppc64 || TT.getArch() == Triple::ppc64le))
104      CM = CodeModel::Medium;
105  }
106  X->initMCCodeGenInfo(RM, CM, OL);
107  return X;
108}
109
110namespace {
111class PPCTargetAsmStreamer : public PPCTargetStreamer {
112  formatted_raw_ostream &OS;
113
114public:
115  PPCTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS)
116      : PPCTargetStreamer(S), OS(OS) {}
117  void emitTCEntry(const MCSymbol &S) override {
118    OS << "\t.tc ";
119    OS << S.getName();
120    OS << "[TC],";
121    OS << S.getName();
122    OS << '\n';
123  }
124  void emitMachine(StringRef CPU) override {
125    OS << "\t.machine " << CPU << '\n';
126  }
127  void emitAbiVersion(int AbiVersion) override {
128    OS << "\t.abiversion " << AbiVersion << '\n';
129  }
130  void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override {
131    const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo();
132
133    OS << "\t.localentry\t";
134    S->print(OS, MAI);
135    OS << ", ";
136    LocalOffset->print(OS, MAI);
137    OS << '\n';
138  }
139};
140
141class PPCTargetELFStreamer : public PPCTargetStreamer {
142public:
143  PPCTargetELFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {}
144  MCELFStreamer &getStreamer() {
145    return static_cast<MCELFStreamer &>(Streamer);
146  }
147  void emitTCEntry(const MCSymbol &S) override {
148    // Creates a R_PPC64_TOC relocation
149    Streamer.EmitValueToAlignment(8);
150    Streamer.EmitSymbolValue(&S, 8);
151  }
152  void emitMachine(StringRef CPU) override {
153    // FIXME: Is there anything to do in here or does this directive only
154    // limit the parser?
155  }
156  void emitAbiVersion(int AbiVersion) override {
157    MCAssembler &MCA = getStreamer().getAssembler();
158    unsigned Flags = MCA.getELFHeaderEFlags();
159    Flags &= ~ELF::EF_PPC64_ABI;
160    Flags |= (AbiVersion & ELF::EF_PPC64_ABI);
161    MCA.setELFHeaderEFlags(Flags);
162  }
163  void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override {
164    MCAssembler &MCA = getStreamer().getAssembler();
165
166    int64_t Res;
167    if (!LocalOffset->evaluateAsAbsolute(Res, MCA))
168      report_fatal_error(".localentry expression must be absolute.");
169
170    unsigned Encoded = ELF::encodePPC64LocalEntryOffset(Res);
171    if (Res != ELF::decodePPC64LocalEntryOffset(Encoded))
172      report_fatal_error(".localentry expression cannot be encoded.");
173
174    unsigned Other = S->getOther();
175    Other &= ~ELF::STO_PPC64_LOCAL_MASK;
176    Other |= Encoded;
177    S->setOther(Other);
178
179    // For GAS compatibility, unless we already saw a .abiversion directive,
180    // set e_flags to indicate ELFv2 ABI.
181    unsigned Flags = MCA.getELFHeaderEFlags();
182    if ((Flags & ELF::EF_PPC64_ABI) == 0)
183      MCA.setELFHeaderEFlags(Flags | 2);
184  }
185  void emitAssignment(MCSymbol *S, const MCExpr *Value) override {
186    auto *Symbol = cast<MCSymbolELF>(S);
187    // When encoding an assignment to set symbol A to symbol B, also copy
188    // the st_other bits encoding the local entry point offset.
189    if (Value->getKind() != MCExpr::SymbolRef)
190      return;
191    const auto &RhsSym = cast<MCSymbolELF>(
192        static_cast<const MCSymbolRefExpr *>(Value)->getSymbol());
193    unsigned Other = Symbol->getOther();
194    Other &= ~ELF::STO_PPC64_LOCAL_MASK;
195    Other |= RhsSym.getOther() & ELF::STO_PPC64_LOCAL_MASK;
196    Symbol->setOther(Other);
197  }
198};
199
200class PPCTargetMachOStreamer : public PPCTargetStreamer {
201public:
202  PPCTargetMachOStreamer(MCStreamer &S) : PPCTargetStreamer(S) {}
203  void emitTCEntry(const MCSymbol &S) override {
204    llvm_unreachable("Unknown pseudo-op: .tc");
205  }
206  void emitMachine(StringRef CPU) override {
207    // FIXME: We should update the CPUType, CPUSubType in the Object file if
208    // the new values are different from the defaults.
209  }
210  void emitAbiVersion(int AbiVersion) override {
211    llvm_unreachable("Unknown pseudo-op: .abiversion");
212  }
213  void emitLocalEntry(MCSymbolELF *S, const MCExpr *LocalOffset) override {
214    llvm_unreachable("Unknown pseudo-op: .localentry");
215  }
216};
217}
218
219static MCTargetStreamer *createAsmTargetStreamer(MCStreamer &S,
220                                                 formatted_raw_ostream &OS,
221                                                 MCInstPrinter *InstPrint,
222                                                 bool isVerboseAsm) {
223  return new PPCTargetAsmStreamer(S, OS);
224}
225
226static MCTargetStreamer *
227createObjectTargetStreamer(MCStreamer &S, const MCSubtargetInfo &STI) {
228  const Triple &TT = STI.getTargetTriple();
229  if (TT.isOSBinFormatELF())
230    return new PPCTargetELFStreamer(S);
231  return new PPCTargetMachOStreamer(S);
232}
233
234static MCInstPrinter *createPPCMCInstPrinter(const Triple &T,
235                                             unsigned SyntaxVariant,
236                                             const MCAsmInfo &MAI,
237                                             const MCInstrInfo &MII,
238                                             const MCRegisterInfo &MRI) {
239  return new PPCInstPrinter(MAI, MII, MRI, T.isOSDarwin());
240}
241
242extern "C" void LLVMInitializePowerPCTargetMC() {
243  for (Target *T : {&ThePPC32Target, &ThePPC64Target, &ThePPC64LETarget}) {
244    // Register the MC asm info.
245    RegisterMCAsmInfoFn C(*T, createPPCMCAsmInfo);
246
247    // Register the MC codegen info.
248    TargetRegistry::RegisterMCCodeGenInfo(*T, createPPCMCCodeGenInfo);
249
250    // Register the MC instruction info.
251    TargetRegistry::RegisterMCInstrInfo(*T, createPPCMCInstrInfo);
252
253    // Register the MC register info.
254    TargetRegistry::RegisterMCRegInfo(*T, createPPCMCRegisterInfo);
255
256    // Register the MC subtarget info.
257    TargetRegistry::RegisterMCSubtargetInfo(*T, createPPCMCSubtargetInfo);
258
259    // Register the MC Code Emitter
260    TargetRegistry::RegisterMCCodeEmitter(*T, createPPCMCCodeEmitter);
261
262    // Register the asm backend.
263    TargetRegistry::RegisterMCAsmBackend(*T, createPPCAsmBackend);
264
265    // Register the object target streamer.
266    TargetRegistry::RegisterObjectTargetStreamer(*T,
267                                                 createObjectTargetStreamer);
268
269    // Register the asm target streamer.
270    TargetRegistry::RegisterAsmTargetStreamer(*T, createAsmTargetStreamer);
271
272    // Register the MCInstPrinter.
273    TargetRegistry::RegisterMCInstPrinter(*T, createPPCMCInstPrinter);
274  }
275}
276