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