lib/Target/X86/X86TargetMachine.cpp

   1 //===-- X86TargetMachine.cpp - Define TargetMachine for the X86 -----------===//
   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 defines the X86 specific subclass of TargetMachine.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "X86MCAsmInfo.h"
  15 #include "X86TargetMachine.h"
  16 #include "X86.h"
  17 #include "llvm/PassManager.h"
  18 #include "llvm/CodeGen/MachineFunction.h"
  19 #include "llvm/CodeGen/Passes.h"
  20 #include "llvm/MC/MCCodeEmitter.h"
  21 #include "llvm/MC/MCStreamer.h"
  22 #include "llvm/Support/FormattedStream.h"
  23 #include "llvm/Target/TargetOptions.h"
  24 #include "llvm/Target/TargetRegistry.h"
  25 using namespace llvm;
  26
  27 static MCAsmInfo *createMCAsmInfo(const Target &T, StringRef TT) {
  28   Triple TheTriple(TT);
  29   switch (TheTriple.getOS()) {
  30   case Triple::Darwin:
  31     return new X86MCAsmInfoDarwin(TheTriple);
  32   case Triple::MinGW32:
  33   case Triple::MinGW64:
  34   case Triple::Cygwin:
  35   case Triple::Win32:
  36     return new X86MCAsmInfoCOFF(TheTriple);
  37   default:
  38     return new X86ELFMCAsmInfo(TheTriple);
  39   }
  40 }
  41
  42 static MCStreamer *createMCStreamer(const Target &T, const std::string &TT,
  43                                     MCContext &Ctx, TargetAsmBackend &TAB,
  44                                     raw_ostream &_OS,
  45                                     MCCodeEmitter *_Emitter,
  46                                     bool RelaxAll,
  47                                     bool NoExecStack) {
  48   Triple TheTriple(TT);
  49   switch (TheTriple.getOS()) {
  50   case Triple::Darwin:
  51     return createMachOStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll);
  52   case Triple::MinGW32:
  53   case Triple::MinGW64:
  54   case Triple::Cygwin:
  55   case Triple::Win32:
  56     return createWinCOFFStreamer(Ctx, TAB, *_Emitter, _OS, RelaxAll);
  57   default:
  58     return createELFStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll, NoExecStack);
  59   }
  60 }
  61
  62 extern "C" void LLVMInitializeX86Target() {
  63   // Register the target.
  64   RegisterTargetMachine<X86_32TargetMachine> X(TheX86_32Target);
  65   RegisterTargetMachine<X86_64TargetMachine> Y(TheX86_64Target);
  66
  67   // Register the target asm info.
  68   RegisterAsmInfoFn A(TheX86_32Target, createMCAsmInfo);
  69   RegisterAsmInfoFn B(TheX86_64Target, createMCAsmInfo);
  70
  71   // Register the code emitter.
  72   TargetRegistry::RegisterCodeEmitter(TheX86_32Target,
  73                                       createX86_32MCCodeEmitter);
  74   TargetRegistry::RegisterCodeEmitter(TheX86_64Target,
  75                                       createX86_64MCCodeEmitter);
  76
  77   // Register the asm backend.
  78   TargetRegistry::RegisterAsmBackend(TheX86_32Target,
  79                                      createX86_32AsmBackend);
  80   TargetRegistry::RegisterAsmBackend(TheX86_64Target,
  81                                      createX86_64AsmBackend);
  82
  83   // Register the object streamer.
  84   TargetRegistry::RegisterObjectStreamer(TheX86_32Target,
  85                                          createMCStreamer);
  86   TargetRegistry::RegisterObjectStreamer(TheX86_64Target,
  87                                          createMCStreamer);
  88 }
  89
  90
  91 X86_32TargetMachine::X86_32TargetMachine(const Target &T, const std::string &TT,
  92                                          const std::string &FS)
  93   : X86TargetMachine(T, TT, FS, false),
  94     DataLayout(getSubtargetImpl()->isTargetDarwin() ?
  95                "e-p:32:32-f64:32:64-i64:32:64-f80:128:128-n8:16:32" :
  96                (getSubtargetImpl()->isTargetCygMing() ||
  97                 getSubtargetImpl()->isTargetWindows()) ?
  98                "e-p:32:32-f64:64:64-i64:64:64-f80:32:32-n8:16:32" :
  99                "e-p:32:32-f64:32:64-i64:32:64-f80:32:32-n8:16:32"),
 100     InstrInfo(*this),
 101     TSInfo(*this),
 102     TLInfo(*this),
 103     JITInfo(*this) {
 104 }
 105
 106
 107 X86_64TargetMachine::X86_64TargetMachine(const Target &T, const std::string &TT,
 108                                          const std::string &FS)
 109   : X86TargetMachine(T, TT, FS, true),
 110     DataLayout("e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128-n8:16:32:64"),
 111     InstrInfo(*this),
 112     TSInfo(*this),
 113     TLInfo(*this),
 114     JITInfo(*this) {
 115 }
 116
 117 /// X86TargetMachine ctor - Create an X86 target.
 118 ///
 119 X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
 120                                    const std::string &FS, bool is64Bit)
 121   : LLVMTargetMachine(T, TT),
 122     Subtarget(TT, FS, is64Bit),
 123     FrameLowering(*this, Subtarget),
 124     ELFWriterInfo(is64Bit, true) {
 125   DefRelocModel = getRelocationModel();
 126
 127   // If no relocation model was picked, default as appropriate for the target.
 128   if (getRelocationModel() == Reloc::Default) {
 129     // Darwin defaults to PIC in 64 bit mode and dynamic-no-pic in 32 bit mode.
 130     // Win64 requires rip-rel addressing, thus we force it to PIC. Otherwise we
 131     // use static relocation model by default.
 132     if (Subtarget.isTargetDarwin()) {
 133       if (Subtarget.is64Bit())
 134         setRelocationModel(Reloc::PIC_);
 135       else
 136         setRelocationModel(Reloc::DynamicNoPIC);
 137     } else if (Subtarget.isTargetWin64())
 138       setRelocationModel(Reloc::PIC_);
 139     else
 140       setRelocationModel(Reloc::Static);
 141   }
 142
 143   assert(getRelocationModel() != Reloc::Default &&
 144          "Relocation mode not picked");
 145
 146   // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
 147   // is defined as a model for code which may be used in static or dynamic
 148   // executables but not necessarily a shared library. On X86-32 we just
 149   // compile in -static mode, in x86-64 we use PIC.
 150   if (getRelocationModel() == Reloc::DynamicNoPIC) {
 151     if (is64Bit)
 152       setRelocationModel(Reloc::PIC_);
 153     else if (!Subtarget.isTargetDarwin())
 154       setRelocationModel(Reloc::Static);
 155   }
 156
 157   // If we are on Darwin, disallow static relocation model in X86-64 mode, since
 158   // the Mach-O file format doesn't support it.
 159   if (getRelocationModel() == Reloc::Static &&
 160       Subtarget.isTargetDarwin() &&
 161       is64Bit)
 162     setRelocationModel(Reloc::PIC_);
 163
 164   // Determine the PICStyle based on the target selected.
 165   if (getRelocationModel() == Reloc::Static) {
 166     // Unless we're in PIC or DynamicNoPIC mode, set the PIC style to None.
 167     Subtarget.setPICStyle(PICStyles::None);
 168   } else if (Subtarget.is64Bit()) {
 169     // PIC in 64 bit mode is always rip-rel.
 170     Subtarget.setPICStyle(PICStyles::RIPRel);
 171   } else if (Subtarget.isTargetCygMing()) {
 172     Subtarget.setPICStyle(PICStyles::None);
 173   } else if (Subtarget.isTargetDarwin()) {
 174     if (getRelocationModel() == Reloc::PIC_)
 175       Subtarget.setPICStyle(PICStyles::StubPIC);
 176     else {
 177       assert(getRelocationModel() == Reloc::DynamicNoPIC);
 178       Subtarget.setPICStyle(PICStyles::StubDynamicNoPIC);
 179     }
 180   } else if (Subtarget.isTargetELF()) {
 181     Subtarget.setPICStyle(PICStyles::GOT);
 182   }
 183
 184   // Finally, if we have "none" as our PIC style, force to static mode.
 185   if (Subtarget.getPICStyle() == PICStyles::None)
 186     setRelocationModel(Reloc::Static);
 187 }
 188
 189 //===----------------------------------------------------------------------===//
 190 // Pass Pipeline Configuration
 191 //===----------------------------------------------------------------------===//
 192
 193 bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
 194                                        CodeGenOpt::Level OptLevel) {
 195   // Install an instruction selector.
 196   PM.add(createX86ISelDag(*this, OptLevel));
 197
 198   // For 32-bit, prepend instructions to set the "global base reg" for PIC.
 199   if (!Subtarget.is64Bit())
 200     PM.add(createGlobalBaseRegPass());
 201
 202   return false;
 203 }
 204
 205 bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
 206                                       CodeGenOpt::Level OptLevel) {
 207   PM.add(createX86MaxStackAlignmentHeuristicPass());
 208   return false;  // -print-machineinstr shouldn't print after this.
 209 }
 210
 211 bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
 212                                        CodeGenOpt::Level OptLevel) {
 213   PM.add(createX86FloatingPointStackifierPass());
 214   return true;  // -print-machineinstr should print after this.
 215 }
 216
 217 bool X86TargetMachine::addPreEmitPass(PassManagerBase &PM,
 218                                       CodeGenOpt::Level OptLevel) {
 219   if (OptLevel != CodeGenOpt::None && Subtarget.hasSSE2()) {
 220     PM.add(createSSEDomainFixPass());
 221     return true;
 222   }
 223   return false;
 224 }
 225
 226 bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
 227                                       CodeGenOpt::Level OptLevel,
 228                                       JITCodeEmitter &JCE) {
 229   // FIXME: Move this to TargetJITInfo!
 230   // On Darwin, do not override 64-bit setting made in X86TargetMachine().
 231   if (DefRelocModel == Reloc::Default &&
 232       (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
 233     setRelocationModel(Reloc::Static);
 234     Subtarget.setPICStyle(PICStyles::None);
 235   }
 236
 237
 238   PM.add(createX86JITCodeEmitterPass(*this, JCE));
 239
 240   return false;
 241 }
 242
 243 void X86TargetMachine::setCodeModelForStatic() {
 244
 245     if (getCodeModel() != CodeModel::Default) return;
 246
 247     // For static codegen, if we're not already set, use Small codegen.
 248     setCodeModel(CodeModel::Small);
 249 }
 250
 251
 252 void X86TargetMachine::setCodeModelForJIT() {
 253
 254   if (getCodeModel() != CodeModel::Default) return;
 255
 256   // 64-bit JIT places everything in the same buffer except external functions.
 257   if (Subtarget.is64Bit())
 258     setCodeModel(CodeModel::Large);
 259   else
 260     setCodeModel(CodeModel::Small);
 261 }