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 "X86TargetMachine.h"
  15 #include "X86.h"
  16 #include "llvm/PassManager.h"
  17 #include "llvm/CodeGen/MachineFunction.h"
  18 #include "llvm/CodeGen/Passes.h"
  19 #include "llvm/MC/MCCodeEmitter.h"
  20 #include "llvm/MC/MCStreamer.h"
  21 #include "llvm/Support/FormattedStream.h"
  22 #include "llvm/Target/TargetOptions.h"
  23 #include "llvm/Target/TargetRegistry.h"
  24 using namespace llvm;
  25
  26 static MCStreamer *createMCStreamer(const Target &T, const std::string &TT,
  27                                     MCContext &Ctx, TargetAsmBackend &TAB,
  28                                     raw_ostream &_OS,
  29                                     MCCodeEmitter *_Emitter,
  30                                     bool RelaxAll,
  31                                     bool NoExecStack) {
  32   Triple TheTriple(TT);
  33
  34   if (TheTriple.isOSDarwin() || TheTriple.getEnvironment() == Triple::MachO)
  35     return createMachOStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll);
  36
  37   if (TheTriple.isOSWindows())
  38     return createWinCOFFStreamer(Ctx, TAB, *_Emitter, _OS, RelaxAll);
  39
  40   return createELFStreamer(Ctx, TAB, _OS, _Emitter, RelaxAll, NoExecStack);
  41 }
  42
  43 extern "C" void LLVMInitializeX86Target() {
  44   // Register the target.
  45   RegisterTargetMachine<X86_32TargetMachine> X(TheX86_32Target);
  46   RegisterTargetMachine<X86_64TargetMachine> Y(TheX86_64Target);
  47
  48   // Register the code emitter.
  49   TargetRegistry::RegisterCodeEmitter(TheX86_32Target,
  50                                       createX86MCCodeEmitter);
  51   TargetRegistry::RegisterCodeEmitter(TheX86_64Target,
  52                                       createX86MCCodeEmitter);
  53
  54   // Register the asm backend.
  55   TargetRegistry::RegisterAsmBackend(TheX86_32Target,
  56                                      createX86_32AsmBackend);
  57   TargetRegistry::RegisterAsmBackend(TheX86_64Target,
  58                                      createX86_64AsmBackend);
  59
  60   // Register the object streamer.
  61   TargetRegistry::RegisterObjectStreamer(TheX86_32Target,
  62                                          createMCStreamer);
  63   TargetRegistry::RegisterObjectStreamer(TheX86_64Target,
  64                                          createMCStreamer);
  65 }
  66
  67
  68 X86_32TargetMachine::X86_32TargetMachine(const Target &T, const std::string &TT,
  69                                          const std::string &CPU,
  70                                          const std::string &FS)
  71   : X86TargetMachine(T, TT, CPU, FS, false),
  72     DataLayout(getSubtargetImpl()->isTargetDarwin() ?
  73                "e-p:32:32-f64:32:64-i64:32:64-f80:128:128-f128:128:128-n8:16:32" :
  74                (getSubtargetImpl()->isTargetCygMing() ||
  75                 getSubtargetImpl()->isTargetWindows()) ?
  76                "e-p:32:32-f64:64:64-i64:64:64-f80:32:32-f128:128:128-n8:16:32" :
  77                "e-p:32:32-f64:32:64-i64:32:64-f80:32:32-f128:128:128-n8:16:32"),
  78     InstrInfo(*this),
  79     TSInfo(*this),
  80     TLInfo(*this),
  81     JITInfo(*this) {
  82 }
  83
  84
  85 X86_64TargetMachine::X86_64TargetMachine(const Target &T, const std::string &TT,
  86                                          const std::string &CPU,
  87                                          const std::string &FS)
  88   : X86TargetMachine(T, TT, CPU, FS, true),
  89     DataLayout("e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128-f128:128:128-n8:16:32:64"),
  90     InstrInfo(*this),
  91     TSInfo(*this),
  92     TLInfo(*this),
  93     JITInfo(*this) {
  94 }
  95
  96 /// X86TargetMachine ctor - Create an X86 target.
  97 ///
  98 X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
  99                                    const std::string &CPU,
 100                                    const std::string &FS, bool is64Bit)
 101   : LLVMTargetMachine(T, TT, CPU, FS),
 102     Subtarget(TT, CPU, FS, StackAlignmentOverride, is64Bit),
 103     FrameLowering(*this, Subtarget),
 104     ELFWriterInfo(is64Bit, true) {
 105   DefRelocModel = getRelocationModel();
 106
 107   // If no relocation model was picked, default as appropriate for the target.
 108   if (getRelocationModel() == Reloc::Default) {
 109     // Darwin defaults to PIC in 64 bit mode and dynamic-no-pic in 32 bit mode.
 110     // Win64 requires rip-rel addressing, thus we force it to PIC. Otherwise we
 111     // use static relocation model by default.
 112     if (Subtarget.isTargetDarwin()) {
 113       if (Subtarget.is64Bit())
 114         setRelocationModel(Reloc::PIC_);
 115       else
 116         setRelocationModel(Reloc::DynamicNoPIC);
 117     } else if (Subtarget.isTargetWin64())
 118       setRelocationModel(Reloc::PIC_);
 119     else
 120       setRelocationModel(Reloc::Static);
 121   }
 122
 123   assert(getRelocationModel() != Reloc::Default &&
 124          "Relocation mode not picked");
 125
 126   // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
 127   // is defined as a model for code which may be used in static or dynamic
 128   // executables but not necessarily a shared library. On X86-32 we just
 129   // compile in -static mode, in x86-64 we use PIC.
 130   if (getRelocationModel() == Reloc::DynamicNoPIC) {
 131     if (is64Bit)
 132       setRelocationModel(Reloc::PIC_);
 133     else if (!Subtarget.isTargetDarwin())
 134       setRelocationModel(Reloc::Static);
 135   }
 136
 137   // If we are on Darwin, disallow static relocation model in X86-64 mode, since
 138   // the Mach-O file format doesn't support it.
 139   if (getRelocationModel() == Reloc::Static &&
 140       Subtarget.isTargetDarwin() &&
 141       is64Bit)
 142     setRelocationModel(Reloc::PIC_);
 143
 144   // Determine the PICStyle based on the target selected.
 145   if (getRelocationModel() == Reloc::Static) {
 146     // Unless we're in PIC or DynamicNoPIC mode, set the PIC style to None.
 147     Subtarget.setPICStyle(PICStyles::None);
 148   } else if (Subtarget.is64Bit()) {
 149     // PIC in 64 bit mode is always rip-rel.
 150     Subtarget.setPICStyle(PICStyles::RIPRel);
 151   } else if (Subtarget.isTargetCygMing()) {
 152     Subtarget.setPICStyle(PICStyles::None);
 153   } else if (Subtarget.isTargetDarwin()) {
 154     if (getRelocationModel() == Reloc::PIC_)
 155       Subtarget.setPICStyle(PICStyles::StubPIC);
 156     else {
 157       assert(getRelocationModel() == Reloc::DynamicNoPIC);
 158       Subtarget.setPICStyle(PICStyles::StubDynamicNoPIC);
 159     }
 160   } else if (Subtarget.isTargetELF()) {
 161     Subtarget.setPICStyle(PICStyles::GOT);
 162   }
 163
 164   // Finally, if we have "none" as our PIC style, force to static mode.
 165   if (Subtarget.getPICStyle() == PICStyles::None)
 166     setRelocationModel(Reloc::Static);
 167
 168   // default to hard float ABI
 169   if (FloatABIType == FloatABI::Default)
 170     FloatABIType = FloatABI::Hard;
 171 }
 172
 173 //===----------------------------------------------------------------------===//
 174 // Pass Pipeline Configuration
 175 //===----------------------------------------------------------------------===//
 176
 177 bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
 178                                        CodeGenOpt::Level OptLevel) {
 179   // Install an instruction selector.
 180   PM.add(createX86ISelDag(*this, OptLevel));
 181
 182   // For 32-bit, prepend instructions to set the "global base reg" for PIC.
 183   if (!Subtarget.is64Bit())
 184     PM.add(createGlobalBaseRegPass());
 185
 186   return false;
 187 }
 188
 189 bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
 190                                       CodeGenOpt::Level OptLevel) {
 191   PM.add(createX86MaxStackAlignmentHeuristicPass());
 192   return false;  // -print-machineinstr shouldn't print after this.
 193 }
 194
 195 bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
 196                                        CodeGenOpt::Level OptLevel) {
 197   PM.add(createX86FloatingPointStackifierPass());
 198   return true;  // -print-machineinstr should print after this.
 199 }
 200
 201 bool X86TargetMachine::addPreEmitPass(PassManagerBase &PM,
 202                                       CodeGenOpt::Level OptLevel) {
 203   if (OptLevel != CodeGenOpt::None && Subtarget.hasSSE2()) {
 204     PM.add(createSSEDomainFixPass());
 205     return true;
 206   }
 207   return false;
 208 }
 209
 210 bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
 211                                       CodeGenOpt::Level OptLevel,
 212                                       JITCodeEmitter &JCE) {
 213   // FIXME: Move this to TargetJITInfo!
 214   // On Darwin, do not override 64-bit setting made in X86TargetMachine().
 215   if (DefRelocModel == Reloc::Default &&
 216       (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
 217     setRelocationModel(Reloc::Static);
 218     Subtarget.setPICStyle(PICStyles::None);
 219   }
 220
 221
 222   PM.add(createX86JITCodeEmitterPass(*this, JCE));
 223
 224   return false;
 225 }
 226
 227 void X86TargetMachine::setCodeModelForStatic() {
 228
 229     if (getCodeModel() != CodeModel::Default) return;
 230
 231     // For static codegen, if we're not already set, use Small codegen.
 232     setCodeModel(CodeModel::Small);
 233 }
 234
 235
 236 void X86TargetMachine::setCodeModelForJIT() {
 237
 238   if (getCodeModel() != CodeModel::Default) return;
 239
 240   // 64-bit JIT places everything in the same buffer except external functions.
 241   if (Subtarget.is64Bit())
 242     setCodeModel(CodeModel::Large);
 243   else
 244     setCodeModel(CodeModel::Small);
 245 }