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
  30   if (TheTriple.isOSDarwin() || TheTriple.getEnvironment() == Triple::MachO)
  31     return new X86MCAsmInfoDarwin(TheTriple);
  32
  33   if (TheTriple.isOSWindows())
  34     return new X86MCAsmInfoCOFF(TheTriple);
  35
  36   return new X86ELFMCAsmInfo(TheTriple);
  37 }
  38
  39 static MCStreamer *createMCStreamer(const Target &T, const std::string &TT,
  40                                     MCContext &Ctx, TargetAsmBackend &TAB,
  41                                     raw_ostream &_OS,
  42                                     MCCodeEmitter *_Emitter,
  43                                     bool RelaxAll,
  44                                     bool NoExecStack) {
  45   Triple TheTriple(TT);
  46
  47   if (TheTriple.isOSDarwin() || TheTriple.getEnvironment() == Triple::MachO)
  48     return createMachOStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll);
  49
  50   if (TheTriple.isOSWindows())
  51     return createWinCOFFStreamer(Ctx, TAB, *_Emitter, _OS, RelaxAll);
  52
  53   return createELFStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll, NoExecStack);
  54 }
  55
  56 extern "C" void LLVMInitializeX86Target() {
  57   // Register the target.
  58   RegisterTargetMachine<X86_32TargetMachine> X(TheX86_32Target);
  59   RegisterTargetMachine<X86_64TargetMachine> Y(TheX86_64Target);
  60
  61   // Register the target asm info.
  62   RegisterAsmInfoFn A(TheX86_32Target, createMCAsmInfo);
  63   RegisterAsmInfoFn B(TheX86_64Target, createMCAsmInfo);
  64
  65   // Register the code emitter.
  66   TargetRegistry::RegisterCodeEmitter(TheX86_32Target,
  67                                       createX86_32MCCodeEmitter);
  68   TargetRegistry::RegisterCodeEmitter(TheX86_64Target,
  69                                       createX86_64MCCodeEmitter);
  70
  71   // Register the asm backend.
  72   TargetRegistry::RegisterAsmBackend(TheX86_32Target,
  73                                      createX86_32AsmBackend);
  74   TargetRegistry::RegisterAsmBackend(TheX86_64Target,
  75                                      createX86_64AsmBackend);
  76
  77   // Register the object streamer.
  78   TargetRegistry::RegisterObjectStreamer(TheX86_32Target,
  79                                          createMCStreamer);
  80   TargetRegistry::RegisterObjectStreamer(TheX86_64Target,
  81                                          createMCStreamer);
  82 }
  83
  84
  85 X86_32TargetMachine::X86_32TargetMachine(const Target &T, const std::string &TT,
  86                                          const std::string &FS)
  87   : X86TargetMachine(T, TT, FS, false),
  88     DataLayout(getSubtargetImpl()->isTargetDarwin() ?
  89                "e-p:32:32-f64:32:64-i64:32:64-f80:128:128-f128:128:128-n8:16:32" :
  90                (getSubtargetImpl()->isTargetCygMing() ||
  91                 getSubtargetImpl()->isTargetWindows()) ?
  92                "e-p:32:32-f64:64:64-i64:64:64-f80:32:32-f128:128:128-n8:16:32" :
  93                "e-p:32:32-f64:32:64-i64:32:64-f80:32:32-f128:128:128-n8:16:32"),
  94     InstrInfo(*this),
  95     TSInfo(*this),
  96     TLInfo(*this),
  97     JITInfo(*this) {
  98 }
  99
 100
 101 X86_64TargetMachine::X86_64TargetMachine(const Target &T, const std::string &TT,
 102                                          const std::string &FS)
 103   : X86TargetMachine(T, TT, FS, true),
 104     DataLayout("e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128-f128:128:128-n8:16:32:64"),
 105     InstrInfo(*this),
 106     TSInfo(*this),
 107     TLInfo(*this),
 108     JITInfo(*this) {
 109 }
 110
 111 /// X86TargetMachine ctor - Create an X86 target.
 112 ///
 113 X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
 114                                    const std::string &FS, bool is64Bit)
 115   : LLVMTargetMachine(T, TT),
 116     Subtarget(TT, FS, is64Bit),
 117     FrameLowering(*this, Subtarget),
 118     ELFWriterInfo(is64Bit, true) {
 119   DefRelocModel = getRelocationModel();
 120
 121   // If no relocation model was picked, default as appropriate for the target.
 122   if (getRelocationModel() == Reloc::Default) {
 123     // Darwin defaults to PIC in 64 bit mode and dynamic-no-pic in 32 bit mode.
 124     // Win64 requires rip-rel addressing, thus we force it to PIC. Otherwise we
 125     // use static relocation model by default.
 126     if (Subtarget.isTargetDarwin()) {
 127       if (Subtarget.is64Bit())
 128         setRelocationModel(Reloc::PIC_);
 129       else
 130         setRelocationModel(Reloc::DynamicNoPIC);
 131     } else if (Subtarget.isTargetWin64())
 132       setRelocationModel(Reloc::PIC_);
 133     else
 134       setRelocationModel(Reloc::Static);
 135   }
 136
 137   assert(getRelocationModel() != Reloc::Default &&
 138          "Relocation mode not picked");
 139
 140   // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
 141   // is defined as a model for code which may be used in static or dynamic
 142   // executables but not necessarily a shared library. On X86-32 we just
 143   // compile in -static mode, in x86-64 we use PIC.
 144   if (getRelocationModel() == Reloc::DynamicNoPIC) {
 145     if (is64Bit)
 146       setRelocationModel(Reloc::PIC_);
 147     else if (!Subtarget.isTargetDarwin())
 148       setRelocationModel(Reloc::Static);
 149   }
 150
 151   // If we are on Darwin, disallow static relocation model in X86-64 mode, since
 152   // the Mach-O file format doesn't support it.
 153   if (getRelocationModel() == Reloc::Static &&
 154       Subtarget.isTargetDarwin() &&
 155       is64Bit)
 156     setRelocationModel(Reloc::PIC_);
 157
 158   // Determine the PICStyle based on the target selected.
 159   if (getRelocationModel() == Reloc::Static) {
 160     // Unless we're in PIC or DynamicNoPIC mode, set the PIC style to None.
 161     Subtarget.setPICStyle(PICStyles::None);
 162   } else if (Subtarget.is64Bit()) {
 163     // PIC in 64 bit mode is always rip-rel.
 164     Subtarget.setPICStyle(PICStyles::RIPRel);
 165   } else if (Subtarget.isTargetCygMing()) {
 166     Subtarget.setPICStyle(PICStyles::None);
 167   } else if (Subtarget.isTargetDarwin()) {
 168     if (getRelocationModel() == Reloc::PIC_)
 169       Subtarget.setPICStyle(PICStyles::StubPIC);
 170     else {
 171       assert(getRelocationModel() == Reloc::DynamicNoPIC);
 172       Subtarget.setPICStyle(PICStyles::StubDynamicNoPIC);
 173     }
 174   } else if (Subtarget.isTargetELF()) {
 175     Subtarget.setPICStyle(PICStyles::GOT);
 176   }
 177
 178   // Finally, if we have "none" as our PIC style, force to static mode.
 179   if (Subtarget.getPICStyle() == PICStyles::None)
 180     setRelocationModel(Reloc::Static);
 181 }
 182
 183 //===----------------------------------------------------------------------===//
 184 // Pass Pipeline Configuration
 185 //===----------------------------------------------------------------------===//
 186
 187 bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
 188                                        CodeGenOpt::Level OptLevel) {
 189   // Install an instruction selector.
 190   PM.add(createX86ISelDag(*this, OptLevel));
 191
 192   // For 32-bit, prepend instructions to set the "global base reg" for PIC.
 193   if (!Subtarget.is64Bit())
 194     PM.add(createGlobalBaseRegPass());
 195
 196   return false;
 197 }
 198
 199 bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
 200                                       CodeGenOpt::Level OptLevel) {
 201   PM.add(createX86MaxStackAlignmentHeuristicPass());
 202   return false;  // -print-machineinstr shouldn't print after this.
 203 }
 204
 205 bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
 206                                        CodeGenOpt::Level OptLevel) {
 207   PM.add(createX86FloatingPointStackifierPass());
 208   return true;  // -print-machineinstr should print after this.
 209 }
 210
 211 bool X86TargetMachine::addPreEmitPass(PassManagerBase &PM,
 212                                       CodeGenOpt::Level OptLevel) {
 213   if (OptLevel != CodeGenOpt::None && Subtarget.hasSSE2()) {
 214     PM.add(createSSEDomainFixPass());
 215     return true;
 216   }
 217   return false;
 218 }
 219
 220 bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
 221                                       CodeGenOpt::Level OptLevel,
 222                                       JITCodeEmitter &JCE) {
 223   // FIXME: Move this to TargetJITInfo!
 224   // On Darwin, do not override 64-bit setting made in X86TargetMachine().
 225   if (DefRelocModel == Reloc::Default &&
 226       (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
 227     setRelocationModel(Reloc::Static);
 228     Subtarget.setPICStyle(PICStyles::None);
 229   }
 230
 231
 232   PM.add(createX86JITCodeEmitterPass(*this, JCE));
 233
 234   return false;
 235 }
 236
 237 void X86TargetMachine::setCodeModelForStatic() {
 238
 239     if (getCodeModel() != CodeModel::Default) return;
 240
 241     // For static codegen, if we're not already set, use Small codegen.
 242     setCodeModel(CodeModel::Small);
 243 }
 244
 245
 246 void X86TargetMachine::setCodeModelForJIT() {
 247
 248   if (getCodeModel() != CodeModel::Default) return;
 249
 250   // 64-bit JIT places everything in the same buffer except external functions.
 251   if (Subtarget.is64Bit())
 252     setCodeModel(CodeModel::Large);
 253   else
 254     setCodeModel(CodeModel::Small);
 255 }