X86TargetMachine.cpp revision 200581 
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/Support/FormattedStream.h"
21#include "llvm/Target/TargetOptions.h"
22#include "llvm/Target/TargetRegistry.h"
23using namespace llvm;
24
25static const MCAsmInfo *createMCAsmInfo(const Target &T, StringRef TT) {
26  Triple TheTriple(TT);
27  switch (TheTriple.getOS()) {
28  case Triple::Darwin:
29    return new X86MCAsmInfoDarwin(TheTriple);
30  case Triple::MinGW32:
31  case Triple::MinGW64:
32  case Triple::Cygwin:
33    return new X86MCAsmInfoCOFF(TheTriple);
34  case Triple::Win32:
35    return new X86WinMCAsmInfo(TheTriple);
36  default:
37    return new X86ELFMCAsmInfo(TheTriple);
38  }
39}
40
41extern "C" void LLVMInitializeX86Target() {
42  // Register the target.
43  RegisterTargetMachine<X86_32TargetMachine> X(TheX86_32Target);
44  RegisterTargetMachine<X86_64TargetMachine> Y(TheX86_64Target);
45
46  // Register the target asm info.
47  RegisterAsmInfoFn A(TheX86_32Target, createMCAsmInfo);
48  RegisterAsmInfoFn B(TheX86_64Target, createMCAsmInfo);
49
50  // Register the code emitter.
51  TargetRegistry::RegisterCodeEmitter(TheX86_32Target, createX86MCCodeEmitter);
52  TargetRegistry::RegisterCodeEmitter(TheX86_64Target, createX86MCCodeEmitter);
53}
54
55
56X86_32TargetMachine::X86_32TargetMachine(const Target &T, const std::string &TT,
57                                         const std::string &FS)
58  : X86TargetMachine(T, TT, FS, false) {
59}
60
61
62X86_64TargetMachine::X86_64TargetMachine(const Target &T, const std::string &TT,
63                                         const std::string &FS)
64  : X86TargetMachine(T, TT, FS, true) {
65}
66
67/// X86TargetMachine ctor - Create an X86 target.
68///
69X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
70                                   const std::string &FS, bool is64Bit)
71  : LLVMTargetMachine(T, TT),
72    Subtarget(TT, FS, is64Bit),
73    DataLayout(Subtarget.getDataLayout()),
74    FrameInfo(TargetFrameInfo::StackGrowsDown,
75              Subtarget.getStackAlignment(),
76              (Subtarget.isTargetWin64() ? -40 :
77               (Subtarget.is64Bit() ? -8 : -4))),
78    InstrInfo(*this), JITInfo(*this), TLInfo(*this), ELFWriterInfo(*this) {
79  DefRelocModel = getRelocationModel();
80
81  // If no relocation model was picked, default as appropriate for the target.
82  if (getRelocationModel() == Reloc::Default) {
83    if (!Subtarget.isTargetDarwin())
84      setRelocationModel(Reloc::Static);
85    else if (Subtarget.is64Bit())
86      setRelocationModel(Reloc::PIC_);
87    else
88      setRelocationModel(Reloc::DynamicNoPIC);
89  }
90
91  assert(getRelocationModel() != Reloc::Default &&
92         "Relocation mode not picked");
93
94  // If no code model is picked, default to small.
95  if (getCodeModel() == CodeModel::Default)
96    setCodeModel(CodeModel::Small);
97
98  // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
99  // is defined as a model for code which may be used in static or dynamic
100  // executables but not necessarily a shared library. On X86-32 we just
101  // compile in -static mode, in x86-64 we use PIC.
102  if (getRelocationModel() == Reloc::DynamicNoPIC) {
103    if (is64Bit)
104      setRelocationModel(Reloc::PIC_);
105    else if (!Subtarget.isTargetDarwin())
106      setRelocationModel(Reloc::Static);
107  }
108
109  // If we are on Darwin, disallow static relocation model in X86-64 mode, since
110  // the Mach-O file format doesn't support it.
111  if (getRelocationModel() == Reloc::Static &&
112      Subtarget.isTargetDarwin() &&
113      is64Bit)
114    setRelocationModel(Reloc::PIC_);
115
116  // Determine the PICStyle based on the target selected.
117  if (getRelocationModel() == Reloc::Static) {
118    // Unless we're in PIC or DynamicNoPIC mode, set the PIC style to None.
119    Subtarget.setPICStyle(PICStyles::None);
120  } else if (Subtarget.isTargetCygMing()) {
121    Subtarget.setPICStyle(PICStyles::None);
122  } else if (Subtarget.isTargetDarwin()) {
123    if (Subtarget.is64Bit())
124      Subtarget.setPICStyle(PICStyles::RIPRel);
125    else if (getRelocationModel() == Reloc::PIC_)
126      Subtarget.setPICStyle(PICStyles::StubPIC);
127    else {
128      assert(getRelocationModel() == Reloc::DynamicNoPIC);
129      Subtarget.setPICStyle(PICStyles::StubDynamicNoPIC);
130    }
131  } else if (Subtarget.isTargetELF()) {
132    if (Subtarget.is64Bit())
133      Subtarget.setPICStyle(PICStyles::RIPRel);
134    else
135      Subtarget.setPICStyle(PICStyles::GOT);
136  }
137
138  // Finally, if we have "none" as our PIC style, force to static mode.
139  if (Subtarget.getPICStyle() == PICStyles::None)
140    setRelocationModel(Reloc::Static);
141}
142
143//===----------------------------------------------------------------------===//
144// Pass Pipeline Configuration
145//===----------------------------------------------------------------------===//
146
147bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
148                                       CodeGenOpt::Level OptLevel) {
149  // Install an instruction selector.
150  PM.add(createX86ISelDag(*this, OptLevel));
151
152  // If we're using Fast-ISel, clean up the mess.
153  if (EnableFastISel)
154    PM.add(createDeadMachineInstructionElimPass());
155
156  // Install a pass to insert x87 FP_REG_KILL instructions, as needed.
157  PM.add(createX87FPRegKillInserterPass());
158
159  return false;
160}
161
162bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
163                                      CodeGenOpt::Level OptLevel) {
164  // Calculate and set max stack object alignment early, so we can decide
165  // whether we will need stack realignment (and thus FP).
166  PM.add(createMaxStackAlignmentCalculatorPass());
167  return false;  // -print-machineinstr shouldn't print after this.
168}
169
170bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
171                                       CodeGenOpt::Level OptLevel) {
172  PM.add(createX86FloatingPointStackifierPass());
173  return true;  // -print-machineinstr should print after this.
174}
175
176bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
177                                      CodeGenOpt::Level OptLevel,
178                                      MachineCodeEmitter &MCE) {
179  // FIXME: Move this to TargetJITInfo!
180  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
181  if (DefRelocModel == Reloc::Default &&
182      (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
183    setRelocationModel(Reloc::Static);
184    Subtarget.setPICStyle(PICStyles::None);
185  }
186
187  // 64-bit JIT places everything in the same buffer except external functions.
188  if (Subtarget.is64Bit())
189      setCodeModel(CodeModel::Large);
190
191  PM.add(createX86CodeEmitterPass(*this, MCE));
192
193  return false;
194}
195
196bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
197                                      CodeGenOpt::Level OptLevel,
198                                      JITCodeEmitter &JCE) {
199  // FIXME: Move this to TargetJITInfo!
200  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
201  if (DefRelocModel == Reloc::Default &&
202      (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
203    setRelocationModel(Reloc::Static);
204    Subtarget.setPICStyle(PICStyles::None);
205  }
206
207  // 64-bit JIT places everything in the same buffer except external functions.
208  if (Subtarget.is64Bit())
209      setCodeModel(CodeModel::Large);
210
211  PM.add(createX86JITCodeEmitterPass(*this, JCE));
212
213  return false;
214}
215
216bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
217                                      CodeGenOpt::Level OptLevel,
218                                      ObjectCodeEmitter &OCE) {
219  PM.add(createX86ObjectCodeEmitterPass(*this, OCE));
220  return false;
221}
222
223bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
224                                            CodeGenOpt::Level OptLevel,
225                                            MachineCodeEmitter &MCE) {
226  PM.add(createX86CodeEmitterPass(*this, MCE));
227  return false;
228}
229
230bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
231                                            CodeGenOpt::Level OptLevel,
232                                            JITCodeEmitter &JCE) {
233  PM.add(createX86JITCodeEmitterPass(*this, JCE));
234  return false;
235}
236
237bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
238                                            CodeGenOpt::Level OptLevel,
239                                            ObjectCodeEmitter &OCE) {
240  PM.add(createX86ObjectCodeEmitterPass(*this, OCE));
241  return false;
242}
243