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/MCELF.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/MCSymbol.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 
33 using 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.
~PPCTargetStreamer()45 PPCTargetStreamer::~PPCTargetStreamer() {}
PPCTargetStreamer(MCStreamer & S)46 PPCTargetStreamer::PPCTargetStreamer(MCStreamer &S) : MCTargetStreamer(S) {}
47 
createPPCMCInstrInfo()48 static MCInstrInfo *createPPCMCInstrInfo() {
49   MCInstrInfo *X = new MCInstrInfo();
50   InitPPCMCInstrInfo(X);
51   return X;
52 }
53 
createPPCMCRegisterInfo(StringRef TT)54 static MCRegisterInfo *createPPCMCRegisterInfo(StringRef TT) {
55   Triple TheTriple(TT);
56   bool isPPC64 = (TheTriple.getArch() == Triple::ppc64 ||
57                   TheTriple.getArch() == Triple::ppc64le);
58   unsigned Flavour = isPPC64 ? 0 : 1;
59   unsigned RA = isPPC64 ? PPC::LR8 : PPC::LR;
60 
61   MCRegisterInfo *X = new MCRegisterInfo();
62   InitPPCMCRegisterInfo(X, RA, Flavour, Flavour);
63   return X;
64 }
65 
createPPCMCSubtargetInfo(StringRef TT,StringRef CPU,StringRef FS)66 static MCSubtargetInfo *createPPCMCSubtargetInfo(StringRef TT, StringRef CPU,
67                                                  StringRef FS) {
68   MCSubtargetInfo *X = new MCSubtargetInfo();
69   InitPPCMCSubtargetInfo(X, TT, CPU, FS);
70   return X;
71 }
72 
createPPCMCAsmInfo(const MCRegisterInfo & MRI,StringRef TT)73 static MCAsmInfo *createPPCMCAsmInfo(const MCRegisterInfo &MRI, StringRef TT) {
74   Triple TheTriple(TT);
75   bool isPPC64 = (TheTriple.getArch() == Triple::ppc64 ||
76                   TheTriple.getArch() == Triple::ppc64le);
77 
78   MCAsmInfo *MAI;
79   if (TheTriple.isOSDarwin())
80     MAI = new PPCMCAsmInfoDarwin(isPPC64, TheTriple);
81   else
82     MAI = new PPCELFMCAsmInfo(isPPC64, TheTriple);
83 
84   // Initial state of the frame pointer is R1.
85   unsigned Reg = isPPC64 ? PPC::X1 : PPC::R1;
86   MCCFIInstruction Inst =
87       MCCFIInstruction::createDefCfa(nullptr, MRI.getDwarfRegNum(Reg, true), 0);
88   MAI->addInitialFrameState(Inst);
89 
90   return MAI;
91 }
92 
createPPCMCCodeGenInfo(StringRef TT,Reloc::Model RM,CodeModel::Model CM,CodeGenOpt::Level OL)93 static MCCodeGenInfo *createPPCMCCodeGenInfo(StringRef TT, Reloc::Model RM,
94                                              CodeModel::Model CM,
95                                              CodeGenOpt::Level OL) {
96   MCCodeGenInfo *X = new MCCodeGenInfo();
97 
98   if (RM == Reloc::Default) {
99     Triple T(TT);
100     if (T.isOSDarwin())
101       RM = Reloc::DynamicNoPIC;
102     else
103       RM = Reloc::Static;
104   }
105   if (CM == CodeModel::Default) {
106     Triple T(TT);
107     if (!T.isOSDarwin() &&
108         (T.getArch() == Triple::ppc64 || T.getArch() == Triple::ppc64le))
109       CM = CodeModel::Medium;
110   }
111   X->InitMCCodeGenInfo(RM, CM, OL);
112   return X;
113 }
114 
115 namespace {
116 class PPCTargetAsmStreamer : public PPCTargetStreamer {
117   formatted_raw_ostream &OS;
118 
119 public:
PPCTargetAsmStreamer(MCStreamer & S,formatted_raw_ostream & OS)120   PPCTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS)
121       : PPCTargetStreamer(S), OS(OS) {}
emitTCEntry(const MCSymbol & S)122   void emitTCEntry(const MCSymbol &S) override {
123     OS << "\t.tc ";
124     OS << S.getName();
125     OS << "[TC],";
126     OS << S.getName();
127     OS << '\n';
128   }
emitMachine(StringRef CPU)129   void emitMachine(StringRef CPU) override {
130     OS << "\t.machine " << CPU << '\n';
131   }
emitAbiVersion(int AbiVersion)132   void emitAbiVersion(int AbiVersion) override {
133     OS << "\t.abiversion " << AbiVersion << '\n';
134   }
emitLocalEntry(MCSymbol * S,const MCExpr * LocalOffset)135   void emitLocalEntry(MCSymbol *S, const MCExpr *LocalOffset) override {
136     OS << "\t.localentry\t" << *S << ", " << *LocalOffset << '\n';
137   }
138 };
139 
140 class PPCTargetELFStreamer : public PPCTargetStreamer {
141 public:
PPCTargetELFStreamer(MCStreamer & S)142   PPCTargetELFStreamer(MCStreamer &S) : PPCTargetStreamer(S) {}
getStreamer()143   MCELFStreamer &getStreamer() {
144     return static_cast<MCELFStreamer &>(Streamer);
145   }
emitTCEntry(const MCSymbol & S)146   void emitTCEntry(const MCSymbol &S) override {
147     // Creates a R_PPC64_TOC relocation
148     Streamer.EmitValueToAlignment(8);
149     Streamer.EmitSymbolValue(&S, 8);
150   }
emitMachine(StringRef CPU)151   void emitMachine(StringRef CPU) override {
152     // FIXME: Is there anything to do in here or does this directive only
153     // limit the parser?
154   }
emitAbiVersion(int AbiVersion)155   void emitAbiVersion(int AbiVersion) override {
156     MCAssembler &MCA = getStreamer().getAssembler();
157     unsigned Flags = MCA.getELFHeaderEFlags();
158     Flags &= ~ELF::EF_PPC64_ABI;
159     Flags |= (AbiVersion & ELF::EF_PPC64_ABI);
160     MCA.setELFHeaderEFlags(Flags);
161   }
emitLocalEntry(MCSymbol * S,const MCExpr * LocalOffset)162   void emitLocalEntry(MCSymbol *S, const MCExpr *LocalOffset) override {
163     MCAssembler &MCA = getStreamer().getAssembler();
164     MCSymbolData &Data = getStreamer().getOrCreateSymbolData(S);
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     // The "other" values are stored in the last 6 bits of the second byte.
175     // The traditional defines for STO values assume the full byte and thus
176     // the shift to pack it.
177     unsigned Other = MCELF::getOther(Data) << 2;
178     Other &= ~ELF::STO_PPC64_LOCAL_MASK;
179     Other |= Encoded;
180     MCELF::setOther(Data, Other >> 2);
181 
182     // For GAS compatibility, unless we already saw a .abiversion directive,
183     // set e_flags to indicate ELFv2 ABI.
184     unsigned Flags = MCA.getELFHeaderEFlags();
185     if ((Flags & ELF::EF_PPC64_ABI) == 0)
186       MCA.setELFHeaderEFlags(Flags | 2);
187   }
emitAssignment(MCSymbol * Symbol,const MCExpr * Value)188   void emitAssignment(MCSymbol *Symbol, const MCExpr *Value) override {
189     // When encoding an assignment to set symbol A to symbol B, also copy
190     // the st_other bits encoding the local entry point offset.
191     if (Value->getKind() != MCExpr::SymbolRef)
192       return;
193     const MCSymbol &RhsSym =
194         static_cast<const MCSymbolRefExpr *>(Value)->getSymbol();
195     MCSymbolData &Data = getStreamer().getOrCreateSymbolData(&RhsSym);
196     MCSymbolData &SymbolData = getStreamer().getOrCreateSymbolData(Symbol);
197     // The "other" values are stored in the last 6 bits of the second byte.
198     // The traditional defines for STO values assume the full byte and thus
199     // the shift to pack it.
200     unsigned Other = MCELF::getOther(SymbolData) << 2;
201     Other &= ~ELF::STO_PPC64_LOCAL_MASK;
202     Other |= (MCELF::getOther(Data) << 2) & ELF::STO_PPC64_LOCAL_MASK;
203     MCELF::setOther(SymbolData, Other >> 2);
204   }
205 };
206 
207 class PPCTargetMachOStreamer : public PPCTargetStreamer {
208 public:
PPCTargetMachOStreamer(MCStreamer & S)209   PPCTargetMachOStreamer(MCStreamer &S) : PPCTargetStreamer(S) {}
emitTCEntry(const MCSymbol & S)210   void emitTCEntry(const MCSymbol &S) override {
211     llvm_unreachable("Unknown pseudo-op: .tc");
212   }
emitMachine(StringRef CPU)213   void emitMachine(StringRef CPU) override {
214     // FIXME: We should update the CPUType, CPUSubType in the Object file if
215     // the new values are different from the defaults.
216   }
emitAbiVersion(int AbiVersion)217   void emitAbiVersion(int AbiVersion) override {
218     llvm_unreachable("Unknown pseudo-op: .abiversion");
219   }
emitLocalEntry(MCSymbol * S,const MCExpr * LocalOffset)220   void emitLocalEntry(MCSymbol *S, const MCExpr *LocalOffset) override {
221     llvm_unreachable("Unknown pseudo-op: .localentry");
222   }
223 };
224 }
225 
createAsmTargetStreamer(MCStreamer & S,formatted_raw_ostream & OS,MCInstPrinter * InstPrint,bool isVerboseAsm)226 static MCTargetStreamer *createAsmTargetStreamer(MCStreamer &S,
227                                                  formatted_raw_ostream &OS,
228                                                  MCInstPrinter *InstPrint,
229                                                  bool isVerboseAsm) {
230   return new PPCTargetAsmStreamer(S, OS);
231 }
232 
233 static MCTargetStreamer *
createObjectTargetStreamer(MCStreamer & S,const MCSubtargetInfo & STI)234 createObjectTargetStreamer(MCStreamer &S, const MCSubtargetInfo &STI) {
235   Triple TT(STI.getTargetTriple());
236   if (TT.getObjectFormat() == Triple::ELF)
237     return new PPCTargetELFStreamer(S);
238   return new PPCTargetMachOStreamer(S);
239 }
240 
createPPCMCInstPrinter(const Triple & T,unsigned SyntaxVariant,const MCAsmInfo & MAI,const MCInstrInfo & MII,const MCRegisterInfo & MRI)241 static MCInstPrinter *createPPCMCInstPrinter(const Triple &T,
242                                              unsigned SyntaxVariant,
243                                              const MCAsmInfo &MAI,
244                                              const MCInstrInfo &MII,
245                                              const MCRegisterInfo &MRI) {
246   return new PPCInstPrinter(MAI, MII, MRI, T.isOSDarwin());
247 }
248 
LLVMInitializePowerPCTargetMC()249 extern "C" void LLVMInitializePowerPCTargetMC() {
250   for (Target *T : {&ThePPC32Target, &ThePPC64Target, &ThePPC64LETarget}) {
251     // Register the MC asm info.
252     RegisterMCAsmInfoFn C(*T, createPPCMCAsmInfo);
253 
254     // Register the MC codegen info.
255     TargetRegistry::RegisterMCCodeGenInfo(*T, createPPCMCCodeGenInfo);
256 
257     // Register the MC instruction info.
258     TargetRegistry::RegisterMCInstrInfo(*T, createPPCMCInstrInfo);
259 
260     // Register the MC register info.
261     TargetRegistry::RegisterMCRegInfo(*T, createPPCMCRegisterInfo);
262 
263     // Register the MC subtarget info.
264     TargetRegistry::RegisterMCSubtargetInfo(*T, createPPCMCSubtargetInfo);
265 
266     // Register the MC Code Emitter
267     TargetRegistry::RegisterMCCodeEmitter(*T, createPPCMCCodeEmitter);
268 
269     // Register the asm backend.
270     TargetRegistry::RegisterMCAsmBackend(*T, createPPCAsmBackend);
271 
272     // Register the object target streamer.
273     TargetRegistry::RegisterObjectTargetStreamer(*T,
274                                                  createObjectTargetStreamer);
275 
276     // Register the asm target streamer.
277     TargetRegistry::RegisterAsmTargetStreamer(*T, createAsmTargetStreamer);
278 
279     // Register the MCInstPrinter.
280     TargetRegistry::RegisterMCInstPrinter(*T, createPPCMCInstPrinter);
281   }
282 }
283