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 "X86TargetAsmInfo.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/Support/FormattedStream.h"
  21 #include "llvm/Target/TargetOptions.h"
  22 #include "llvm/Target/TargetRegistry.h"
  23 using namespace llvm;
  24
  25 extern "C" void LLVMInitializeX86Target() {
  26   // Register the target.
  27   RegisterTargetMachine<X86_32TargetMachine> X(TheX86_32Target);
  28   RegisterTargetMachine<X86_64TargetMachine> Y(TheX86_64Target);
  29 }
  30
  31 const TargetAsmInfo *X86TargetMachine::createTargetAsmInfo() const {
  32   switch (Subtarget.TargetType) {
  33   default: llvm_unreachable("unknown subtarget type");
  34   case X86Subtarget::isDarwin:
  35     return new X86DarwinTargetAsmInfo(*this);
  36   case X86Subtarget::isELF:
  37     return new X86ELFTargetAsmInfo(*this);
  38   case X86Subtarget::isMingw:
  39   case X86Subtarget::isCygwin:
  40     return new X86COFFTargetAsmInfo(*this);
  41   case X86Subtarget::isWindows:
  42     return new X86WinTargetAsmInfo(*this);
  43   }
  44 }
  45
  46 X86_32TargetMachine::X86_32TargetMachine(const Target &T, const std::string &TT,
  47                                          const std::string &FS)
  48   : X86TargetMachine(T, TT, FS, false) {
  49 }
  50
  51
  52 X86_64TargetMachine::X86_64TargetMachine(const Target &T, const std::string &TT,
  53                                          const std::string &FS)
  54   : X86TargetMachine(T, TT, FS, true) {
  55 }
  56
  57 /// X86TargetMachine ctor - Create an X86 target.
  58 ///
  59 X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
  60                                    const std::string &FS, bool is64Bit)
  61   : LLVMTargetMachine(T),
  62     Subtarget(TT, FS, is64Bit),
  63     DataLayout(Subtarget.getDataLayout()),
  64     FrameInfo(TargetFrameInfo::StackGrowsDown,
  65               Subtarget.getStackAlignment(),
  66               (Subtarget.isTargetWin64() ? -40 :
  67                (Subtarget.is64Bit() ? -8 : -4))),
  68     InstrInfo(*this), JITInfo(*this), TLInfo(*this), ELFWriterInfo(*this) {
  69   DefRelocModel = getRelocationModel();
  70
  71   // If no relocation model was picked, default as appropriate for the target.
  72   if (getRelocationModel() == Reloc::Default) {
  73     if (!Subtarget.isTargetDarwin())
  74       setRelocationModel(Reloc::Static);
  75     else if (Subtarget.is64Bit())
  76       setRelocationModel(Reloc::PIC_);
  77     else
  78       setRelocationModel(Reloc::DynamicNoPIC);
  79   }
  80
  81   assert(getRelocationModel() != Reloc::Default &&
  82          "Relocation mode not picked");
  83
  84   // If no code model is picked, default to small.
  85   if (getCodeModel() == CodeModel::Default)
  86     setCodeModel(CodeModel::Small);
  87
  88   // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
  89   // is defined as a model for code which may be used in static or dynamic
  90   // executables but not necessarily a shared library. On X86-32 we just
  91   // compile in -static mode, in x86-64 we use PIC.
  92   if (getRelocationModel() == Reloc::DynamicNoPIC) {
  93     if (is64Bit)
  94       setRelocationModel(Reloc::PIC_);
  95     else if (!Subtarget.isTargetDarwin())
  96       setRelocationModel(Reloc::Static);
  97   }
  98
  99   // If we are on Darwin, disallow static relocation model in X86-64 mode, since
 100   // the Mach-O file format doesn't support it.
 101   if (getRelocationModel() == Reloc::Static &&
 102       Subtarget.isTargetDarwin() &&
 103       is64Bit)
 104     setRelocationModel(Reloc::PIC_);
 105
 106   // Determine the PICStyle based on the target selected.
 107   if (getRelocationModel() == Reloc::Static) {
 108     // Unless we're in PIC or DynamicNoPIC mode, set the PIC style to None.
 109     Subtarget.setPICStyle(PICStyles::None);
 110   } else if (Subtarget.isTargetCygMing()) {
 111     Subtarget.setPICStyle(PICStyles::None);
 112   } else if (Subtarget.isTargetDarwin()) {
 113     if (Subtarget.is64Bit())
 114       Subtarget.setPICStyle(PICStyles::RIPRel);
 115     else if (getRelocationModel() == Reloc::PIC_)
 116       Subtarget.setPICStyle(PICStyles::StubPIC);
 117     else {
 118       assert(getRelocationModel() == Reloc::DynamicNoPIC);
 119       Subtarget.setPICStyle(PICStyles::StubDynamicNoPIC);
 120     }
 121   } else if (Subtarget.isTargetELF()) {
 122     if (Subtarget.is64Bit())
 123       Subtarget.setPICStyle(PICStyles::RIPRel);
 124     else
 125       Subtarget.setPICStyle(PICStyles::GOT);
 126   }
 127
 128   // Finally, if we have "none" as our PIC style, force to static mode.
 129   if (Subtarget.getPICStyle() == PICStyles::None)
 130     setRelocationModel(Reloc::Static);
 131 }
 132
 133 //===----------------------------------------------------------------------===//
 134 // Pass Pipeline Configuration
 135 //===----------------------------------------------------------------------===//
 136
 137 bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
 138                                        CodeGenOpt::Level OptLevel) {
 139   // Install an instruction selector.
 140   PM.add(createX86ISelDag(*this, OptLevel));
 141
 142   // If we're using Fast-ISel, clean up the mess.
 143   if (EnableFastISel)
 144     PM.add(createDeadMachineInstructionElimPass());
 145
 146   // Install a pass to insert x87 FP_REG_KILL instructions, as needed.
 147   PM.add(createX87FPRegKillInserterPass());
 148
 149   return false;
 150 }
 151
 152 bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
 153                                       CodeGenOpt::Level OptLevel) {
 154   // Calculate and set max stack object alignment early, so we can decide
 155   // whether we will need stack realignment (and thus FP).
 156   PM.add(createX86MaxStackAlignmentCalculatorPass());
 157   return false;  // -print-machineinstr shouldn't print after this.
 158 }
 159
 160 bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
 161                                        CodeGenOpt::Level OptLevel) {
 162   PM.add(createX86FloatingPointStackifierPass());
 163   return true;  // -print-machineinstr should print after this.
 164 }
 165
 166 bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
 167                                       CodeGenOpt::Level OptLevel,
 168                                       MachineCodeEmitter &MCE) {
 169   // FIXME: Move this to TargetJITInfo!
 170   // On Darwin, do not override 64-bit setting made in X86TargetMachine().
 171   if (DefRelocModel == Reloc::Default &&
 172       (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
 173     setRelocationModel(Reloc::Static);
 174     Subtarget.setPICStyle(PICStyles::None);
 175   }
 176
 177   // 64-bit JIT places everything in the same buffer except external functions.
 178   // On Darwin, use small code model but hack the call instruction for
 179   // externals.  Elsewhere, do not assume globals are in the lower 4G.
 180   if (Subtarget.is64Bit()) {
 181     if (Subtarget.isTargetDarwin())
 182       setCodeModel(CodeModel::Small);
 183     else
 184       setCodeModel(CodeModel::Large);
 185   }
 186
 187   PM.add(createX86CodeEmitterPass(*this, MCE));
 188
 189   return false;
 190 }
 191
 192 bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
 193                                       CodeGenOpt::Level OptLevel,
 194                                       JITCodeEmitter &JCE) {
 195   // FIXME: Move this to TargetJITInfo!
 196   // On Darwin, do not override 64-bit setting made in X86TargetMachine().
 197   if (DefRelocModel == Reloc::Default &&
 198       (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
 199     setRelocationModel(Reloc::Static);
 200     Subtarget.setPICStyle(PICStyles::None);
 201   }
 202
 203   // 64-bit JIT places everything in the same buffer except external functions.
 204   // On Darwin, use small code model but hack the call instruction for
 205   // externals.  Elsewhere, do not assume globals are in the lower 4G.
 206   if (Subtarget.is64Bit()) {
 207     if (Subtarget.isTargetDarwin())
 208       setCodeModel(CodeModel::Small);
 209     else
 210       setCodeModel(CodeModel::Large);
 211   }
 212
 213   PM.add(createX86JITCodeEmitterPass(*this, JCE));
 214
 215   return false;
 216 }
 217
 218 bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
 219                                       CodeGenOpt::Level OptLevel,
 220                                       ObjectCodeEmitter &OCE) {
 221   PM.add(createX86ObjectCodeEmitterPass(*this, OCE));
 222   return false;
 223 }
 224
 225 bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
 226                                             CodeGenOpt::Level OptLevel,
 227                                             MachineCodeEmitter &MCE) {
 228   PM.add(createX86CodeEmitterPass(*this, MCE));
 229   return false;
 230 }
 231
 232 bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
 233                                             CodeGenOpt::Level OptLevel,
 234                                             JITCodeEmitter &JCE) {
 235   PM.add(createX86JITCodeEmitterPass(*this, JCE));
 236   return false;
 237 }
 238
 239 bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
 240                                             CodeGenOpt::Level OptLevel,
 241                                             ObjectCodeEmitter &OCE) {
 242   PM.add(createX86ObjectCodeEmitterPass(*this, OCE));
 243   return false;
 244 }