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   Triple TheTriple(TT);
  48   switch (TheTriple.getOS()) {
  49   case Triple::Darwin:
  50     return createMachOStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll);
  51   case Triple::MinGW32:
  52   case Triple::MinGW64:
  53   case Triple::Cygwin:
  54   case Triple::Win32:
  55     return createWinCOFFStreamer(Ctx, TAB, *_Emitter, _OS, RelaxAll);
  56   default:
  57     return createELFStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll);
  58   }
  59 }
  60
  61 extern "C" void LLVMInitializeX86Target() {
  62   // Register the target.
  63   RegisterTargetMachine<X86_32TargetMachine> X(TheX86_32Target);
  64   RegisterTargetMachine<X86_64TargetMachine> Y(TheX86_64Target);
  65
  66   // Register the target asm info.
  67   RegisterAsmInfoFn A(TheX86_32Target, createMCAsmInfo);
  68   RegisterAsmInfoFn B(TheX86_64Target, createMCAsmInfo);
  69
  70   // Register the code emitter.
  71   TargetRegistry::RegisterCodeEmitter(TheX86_32Target,
  72                                       createX86_32MCCodeEmitter);
  73   TargetRegistry::RegisterCodeEmitter(TheX86_64Target,
  74                                       createX86_64MCCodeEmitter);
  75
  76   // Register the asm backend.
  77   TargetRegistry::RegisterAsmBackend(TheX86_32Target,
  78                                      createX86_32AsmBackend);
  79   TargetRegistry::RegisterAsmBackend(TheX86_64Target,
  80                                      createX86_64AsmBackend);
  81
  82   // Register the object streamer.
  83   TargetRegistry::RegisterObjectStreamer(TheX86_32Target,
  84                                          createMCStreamer);
  85   TargetRegistry::RegisterObjectStreamer(TheX86_64Target,
  86                                          createMCStreamer);
  87 }
  88
  89
  90 X86_32TargetMachine::X86_32TargetMachine(const Target &T, const std::string &TT,
  91                                          const std::string &FS)
  92   : X86TargetMachine(T, TT, FS, false),
  93     DataLayout(getSubtargetImpl()->isTargetDarwin() ?
  94                "e-p:32:32-f64:32:64-i64:32:64-f80:128:128-n8:16:32" :
  95                (getSubtargetImpl()->isTargetCygMing() ||
  96                 getSubtargetImpl()->isTargetWindows()) ?
  97                "e-p:32:32-f64:64:64-i64:64:64-f80:32:32-n8:16:32" :
  98                "e-p:32:32-f64:32:64-i64:32:64-f80:32:32-n8:16:32"),
  99     InstrInfo(*this),
 100     TSInfo(*this),
 101     TLInfo(*this),
 102     JITInfo(*this) {
 103 }
 104
 105
 106 X86_64TargetMachine::X86_64TargetMachine(const Target &T, const std::string &TT,
 107                                          const std::string &FS)
 108   : X86TargetMachine(T, TT, FS, true),
 109     DataLayout("e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128-n8:16:32:64"),
 110     InstrInfo(*this),
 111     TSInfo(*this),
 112     TLInfo(*this),
 113     JITInfo(*this) {
 114 }
 115
 116 /// X86TargetMachine ctor - Create an X86 target.
 117 ///
 118 X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
 119                                    const std::string &FS, bool is64Bit)
 120   : LLVMTargetMachine(T, TT),
 121     Subtarget(TT, FS, is64Bit),
 122     FrameInfo(TargetFrameInfo::StackGrowsDown,
 123               Subtarget.getStackAlignment(),
 124               (Subtarget.isTargetWin64() ? -40 :
 125                (Subtarget.is64Bit() ? -8 : -4))),
 126     ELFWriterInfo(is64Bit, true) {
 127   DefRelocModel = getRelocationModel();
 128
 129   // If no relocation model was picked, default as appropriate for the target.
 130   if (getRelocationModel() == Reloc::Default) {
 131     // Darwin defaults to PIC in 64 bit mode and dynamic-no-pic in 32 bit mode.
 132     // Win64 requires rip-rel addressing, thus we force it to PIC. Otherwise we
 133     // use static relocation model by default.
 134     if (Subtarget.isTargetDarwin()) {
 135       if (Subtarget.is64Bit())
 136         setRelocationModel(Reloc::PIC_);
 137       else
 138         setRelocationModel(Reloc::DynamicNoPIC);
 139     } else if (Subtarget.isTargetWin64())
 140       setRelocationModel(Reloc::PIC_);
 141     else
 142       setRelocationModel(Reloc::Static);
 143   }
 144
 145   assert(getRelocationModel() != Reloc::Default &&
 146          "Relocation mode not picked");
 147
 148   // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
 149   // is defined as a model for code which may be used in static or dynamic
 150   // executables but not necessarily a shared library. On X86-32 we just
 151   // compile in -static mode, in x86-64 we use PIC.
 152   if (getRelocationModel() == Reloc::DynamicNoPIC) {
 153     if (is64Bit)
 154       setRelocationModel(Reloc::PIC_);
 155     else if (!Subtarget.isTargetDarwin())
 156       setRelocationModel(Reloc::Static);
 157   }
 158
 159   // If we are on Darwin, disallow static relocation model in X86-64 mode, since
 160   // the Mach-O file format doesn't support it.
 161   if (getRelocationModel() == Reloc::Static &&
 162       Subtarget.isTargetDarwin() &&
 163       is64Bit)
 164     setRelocationModel(Reloc::PIC_);
 165
 166   // Determine the PICStyle based on the target selected.
 167   if (getRelocationModel() == Reloc::Static) {
 168     // Unless we're in PIC or DynamicNoPIC mode, set the PIC style to None.
 169     Subtarget.setPICStyle(PICStyles::None);
 170   } else if (Subtarget.is64Bit()) {
 171     // PIC in 64 bit mode is always rip-rel.
 172     Subtarget.setPICStyle(PICStyles::RIPRel);
 173   } else if (Subtarget.isTargetCygMing()) {
 174     Subtarget.setPICStyle(PICStyles::None);
 175   } else if (Subtarget.isTargetDarwin()) {
 176     if (getRelocationModel() == Reloc::PIC_)
 177       Subtarget.setPICStyle(PICStyles::StubPIC);
 178     else {
 179       assert(getRelocationModel() == Reloc::DynamicNoPIC);
 180       Subtarget.setPICStyle(PICStyles::StubDynamicNoPIC);
 181     }
 182   } else if (Subtarget.isTargetELF()) {
 183     Subtarget.setPICStyle(PICStyles::GOT);
 184   }
 185
 186   // Finally, if we have "none" as our PIC style, force to static mode.
 187   if (Subtarget.getPICStyle() == PICStyles::None)
 188     setRelocationModel(Reloc::Static);
 189 }
 190
 191 //===----------------------------------------------------------------------===//
 192 // Pass Pipeline Configuration
 193 //===----------------------------------------------------------------------===//
 194
 195 bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
 196                                        CodeGenOpt::Level OptLevel) {
 197   // Install an instruction selector.
 198   PM.add(createX86ISelDag(*this, OptLevel));
 199
 200   // For 32-bit, prepend instructions to set the "global base reg" for PIC.
 201   if (!Subtarget.is64Bit())
 202     PM.add(createGlobalBaseRegPass());
 203
 204   return false;
 205 }
 206
 207 bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
 208                                       CodeGenOpt::Level OptLevel) {
 209   PM.add(createX86MaxStackAlignmentHeuristicPass());
 210   return false;  // -print-machineinstr shouldn't print after this.
 211 }
 212
 213 bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
 214                                        CodeGenOpt::Level OptLevel) {
 215   PM.add(createX86FloatingPointStackifierPass());
 216   return true;  // -print-machineinstr should print after this.
 217 }
 218
 219 bool X86TargetMachine::addPreEmitPass(PassManagerBase &PM,
 220                                       CodeGenOpt::Level OptLevel) {
 221   if (OptLevel != CodeGenOpt::None && Subtarget.hasSSE2()) {
 222     PM.add(createSSEDomainFixPass());
 223     return true;
 224   }
 225   return false;
 226 }
 227
 228 bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
 229                                       CodeGenOpt::Level OptLevel,
 230                                       JITCodeEmitter &JCE) {
 231   // FIXME: Move this to TargetJITInfo!
 232   // On Darwin, do not override 64-bit setting made in X86TargetMachine().
 233   if (DefRelocModel == Reloc::Default &&
 234       (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
 235     setRelocationModel(Reloc::Static);
 236     Subtarget.setPICStyle(PICStyles::None);
 237   }
 238
 239
 240   PM.add(createX86JITCodeEmitterPass(*this, JCE));
 241
 242   return false;
 243 }
 244
 245 void X86TargetMachine::setCodeModelForStatic() {
 246
 247     if (getCodeModel() != CodeModel::Default) return;
 248
 249     // For static codegen, if we're not already set, use Small codegen.
 250     setCodeModel(CodeModel::Small);
 251 }
 252
 253
 254 void X86TargetMachine::setCodeModelForJIT() {
 255
 256   if (getCodeModel() != CodeModel::Default) return;
 257
 258   // 64-bit JIT places everything in the same buffer except external functions.
 259   if (Subtarget.is64Bit())
 260     setCodeModel(CodeModel::Large);
 261   else
 262     setCodeModel(CodeModel::Small);
 263 }