X86TargetMachine.cpp revision 194612 
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/Module.h"
18#include "llvm/PassManager.h"
19#include "llvm/CodeGen/MachineFunction.h"
20#include "llvm/CodeGen/Passes.h"
21#include "llvm/Support/raw_ostream.h"
22#include "llvm/Target/TargetOptions.h"
23#include "llvm/Target/TargetMachineRegistry.h"
24using namespace llvm;
25
26/// X86TargetMachineModule - Note that this is used on hosts that cannot link
27/// in a library unless there are references into the library.  In particular,
28/// it seems that it is not possible to get things to work on Win32 without
29/// this.  Though it is unused, do not remove it.
30extern "C" int X86TargetMachineModule;
31int X86TargetMachineModule = 0;
32
33// Register the target.
34static RegisterTarget<X86_32TargetMachine>
35X("x86",    "32-bit X86: Pentium-Pro and above");
36static RegisterTarget<X86_64TargetMachine>
37Y("x86-64", "64-bit X86: EM64T and AMD64");
38
39// Force static initialization when called from llvm/InitializeAllTargets.h
40namespace llvm {
41  void InitializeX86Target() { }
42}
43
44// No assembler printer by default
45X86TargetMachine::AsmPrinterCtorFn X86TargetMachine::AsmPrinterCtor = 0;
46
47const TargetAsmInfo *X86TargetMachine::createTargetAsmInfo() const {
48  if (Subtarget.isFlavorIntel())
49    return new X86WinTargetAsmInfo(*this);
50  else
51    switch (Subtarget.TargetType) {
52     case X86Subtarget::isDarwin:
53      return new X86DarwinTargetAsmInfo(*this);
54     case X86Subtarget::isELF:
55      return new X86ELFTargetAsmInfo(*this);
56     case X86Subtarget::isMingw:
57     case X86Subtarget::isCygwin:
58      return new X86COFFTargetAsmInfo(*this);
59     case X86Subtarget::isWindows:
60      return new X86WinTargetAsmInfo(*this);
61     default:
62      return new X86GenericTargetAsmInfo(*this);
63    }
64}
65
66unsigned X86_32TargetMachine::getJITMatchQuality() {
67#if defined(i386) || defined(__i386__) || defined(__x86__) || defined(_M_IX86)
68  return 10;
69#endif
70  return 0;
71}
72
73unsigned X86_64TargetMachine::getJITMatchQuality() {
74#if defined(__x86_64__) || defined(_M_AMD64)
75  return 10;
76#endif
77  return 0;
78}
79
80unsigned X86_32TargetMachine::getModuleMatchQuality(const Module &M) {
81  // We strongly match "i[3-9]86-*".
82  std::string TT = M.getTargetTriple();
83  if (TT.size() >= 5 && TT[0] == 'i' && TT[2] == '8' && TT[3] == '6' &&
84      TT[4] == '-' && TT[1] - '3' < 6)
85    return 20;
86  // If the target triple is something non-X86, we don't match.
87  if (!TT.empty()) return 0;
88
89  if (M.getEndianness()  == Module::LittleEndian &&
90      M.getPointerSize() == Module::Pointer32)
91    return 10;                                   // Weak match
92  else if (M.getEndianness() != Module::AnyEndianness ||
93           M.getPointerSize() != Module::AnyPointerSize)
94    return 0;                                    // Match for some other target
95
96  return getJITMatchQuality()/2;
97}
98
99unsigned X86_64TargetMachine::getModuleMatchQuality(const Module &M) {
100  // We strongly match "x86_64-*".
101  std::string TT = M.getTargetTriple();
102  if (TT.size() >= 7 && TT[0] == 'x' && TT[1] == '8' && TT[2] == '6' &&
103      TT[3] == '_' && TT[4] == '6' && TT[5] == '4' && TT[6] == '-')
104    return 20;
105
106  // We strongly match "amd64-*".
107  if (TT.size() >= 6 && TT[0] == 'a' && TT[1] == 'm' && TT[2] == 'd' &&
108      TT[3] == '6' && TT[4] == '4' && TT[5] == '-')
109    return 20;
110
111  // If the target triple is something non-X86-64, we don't match.
112  if (!TT.empty()) return 0;
113
114  if (M.getEndianness()  == Module::LittleEndian &&
115      M.getPointerSize() == Module::Pointer64)
116    return 10;                                   // Weak match
117  else if (M.getEndianness() != Module::AnyEndianness ||
118           M.getPointerSize() != Module::AnyPointerSize)
119    return 0;                                    // Match for some other target
120
121  return getJITMatchQuality()/2;
122}
123
124X86_32TargetMachine::X86_32TargetMachine(const Module &M, const std::string &FS)
125  : X86TargetMachine(M, FS, false) {
126}
127
128
129X86_64TargetMachine::X86_64TargetMachine(const Module &M, const std::string &FS)
130  : X86TargetMachine(M, FS, true) {
131}
132
133/// X86TargetMachine ctor - Create an ILP32 architecture model
134///
135X86TargetMachine::X86TargetMachine(const Module &M, const std::string &FS,
136                                   bool is64Bit)
137  : Subtarget(M, FS, is64Bit),
138    DataLayout(Subtarget.getDataLayout()),
139    FrameInfo(TargetFrameInfo::StackGrowsDown,
140              Subtarget.getStackAlignment(), Subtarget.is64Bit() ? -8 : -4),
141    InstrInfo(*this), JITInfo(*this), TLInfo(*this), ELFWriterInfo(*this) {
142  DefRelocModel = getRelocationModel();
143  // FIXME: Correctly select PIC model for Win64 stuff
144  if (getRelocationModel() == Reloc::Default) {
145    if (Subtarget.isTargetDarwin() ||
146        (Subtarget.isTargetCygMing() && !Subtarget.isTargetWin64()))
147      setRelocationModel(Reloc::DynamicNoPIC);
148    else
149      setRelocationModel(Reloc::Static);
150  }
151
152  // ELF doesn't have a distinct dynamic-no-PIC model. Dynamic-no-PIC
153  // is defined as a model for code which may be used in static or
154  // dynamic executables but not necessarily a shared library. On ELF
155  // implement this by using the Static model.
156  if (Subtarget.isTargetELF() &&
157      getRelocationModel() == Reloc::DynamicNoPIC)
158    setRelocationModel(Reloc::Static);
159
160  if (Subtarget.is64Bit()) {
161    // No DynamicNoPIC support under X86-64.
162    if (getRelocationModel() == Reloc::DynamicNoPIC)
163      setRelocationModel(Reloc::PIC_);
164    // Default X86-64 code model is small.
165    if (getCodeModel() == CodeModel::Default)
166      setCodeModel(CodeModel::Small);
167  }
168
169  if (Subtarget.isTargetCygMing())
170    Subtarget.setPICStyle(PICStyles::WinPIC);
171  else if (Subtarget.isTargetDarwin()) {
172    if (Subtarget.is64Bit())
173      Subtarget.setPICStyle(PICStyles::RIPRel);
174    else
175      Subtarget.setPICStyle(PICStyles::Stub);
176  } else if (Subtarget.isTargetELF()) {
177    if (Subtarget.is64Bit())
178      Subtarget.setPICStyle(PICStyles::RIPRel);
179    else
180      Subtarget.setPICStyle(PICStyles::GOT);
181  }
182}
183
184//===----------------------------------------------------------------------===//
185// Pass Pipeline Configuration
186//===----------------------------------------------------------------------===//
187
188bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
189                                       CodeGenOpt::Level OptLevel) {
190  // Install an instruction selector.
191  PM.add(createX86ISelDag(*this, OptLevel));
192
193  // If we're using Fast-ISel, clean up the mess.
194  if (EnableFastISel)
195    PM.add(createDeadMachineInstructionElimPass());
196
197  // Install a pass to insert x87 FP_REG_KILL instructions, as needed.
198  PM.add(createX87FPRegKillInserterPass());
199
200  return false;
201}
202
203bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
204                                      CodeGenOpt::Level OptLevel) {
205  // Calculate and set max stack object alignment early, so we can decide
206  // whether we will need stack realignment (and thus FP).
207  PM.add(createX86MaxStackAlignmentCalculatorPass());
208  return false;  // -print-machineinstr shouldn't print after this.
209}
210
211bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
212                                       CodeGenOpt::Level OptLevel) {
213  PM.add(createX86FloatingPointStackifierPass());
214  return true;  // -print-machineinstr should print after this.
215}
216
217bool X86TargetMachine::addAssemblyEmitter(PassManagerBase &PM,
218                                          CodeGenOpt::Level OptLevel,
219                                          bool Verbose,
220                                          raw_ostream &Out) {
221  // FIXME: Move this somewhere else!
222  // On Darwin, override 64-bit static relocation to pic_ since the
223  // assembler doesn't support it.
224  if (DefRelocModel == Reloc::Static &&
225      Subtarget.isTargetDarwin() && Subtarget.is64Bit())
226    setRelocationModel(Reloc::PIC_);
227
228  assert(AsmPrinterCtor && "AsmPrinter was not linked in");
229  if (AsmPrinterCtor)
230    PM.add(AsmPrinterCtor(Out, *this, OptLevel, Verbose));
231  return false;
232}
233
234bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
235                                      CodeGenOpt::Level OptLevel,
236                                      bool DumpAsm,
237                                      MachineCodeEmitter &MCE) {
238  // FIXME: Move this to TargetJITInfo!
239  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
240  if (DefRelocModel == Reloc::Default &&
241        (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit()))
242    setRelocationModel(Reloc::Static);
243
244  // 64-bit JIT places everything in the same buffer except external functions.
245  // On Darwin, use small code model but hack the call instruction for
246  // externals.  Elsewhere, do not assume globals are in the lower 4G.
247  if (Subtarget.is64Bit()) {
248    if (Subtarget.isTargetDarwin())
249      setCodeModel(CodeModel::Small);
250    else
251      setCodeModel(CodeModel::Large);
252  }
253
254  PM.add(createX86CodeEmitterPass(*this, MCE));
255  if (DumpAsm) {
256    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
257    if (AsmPrinterCtor)
258      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
259  }
260
261  return false;
262}
263
264bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
265                                      CodeGenOpt::Level OptLevel,
266                                      bool DumpAsm,
267                                      JITCodeEmitter &JCE) {
268  // FIXME: Move this to TargetJITInfo!
269  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
270  if (DefRelocModel == Reloc::Default &&
271        (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit()))
272    setRelocationModel(Reloc::Static);
273
274  // 64-bit JIT places everything in the same buffer except external functions.
275  // On Darwin, use small code model but hack the call instruction for
276  // externals.  Elsewhere, do not assume globals are in the lower 4G.
277  if (Subtarget.is64Bit()) {
278    if (Subtarget.isTargetDarwin())
279      setCodeModel(CodeModel::Small);
280    else
281      setCodeModel(CodeModel::Large);
282  }
283
284  PM.add(createX86JITCodeEmitterPass(*this, JCE));
285  if (DumpAsm) {
286    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
287    if (AsmPrinterCtor)
288      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
289  }
290
291  return false;
292}
293
294bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
295                                            CodeGenOpt::Level OptLevel,
296                                            bool DumpAsm,
297                                            MachineCodeEmitter &MCE) {
298  PM.add(createX86CodeEmitterPass(*this, MCE));
299  if (DumpAsm) {
300    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
301    if (AsmPrinterCtor)
302      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
303  }
304
305  return false;
306}
307
308bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
309                                            CodeGenOpt::Level OptLevel,
310                                            bool DumpAsm,
311                                            JITCodeEmitter &JCE) {
312  PM.add(createX86JITCodeEmitterPass(*this, JCE));
313  if (DumpAsm) {
314    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
315    if (AsmPrinterCtor)
316      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
317  }
318
319  return false;
320}
321
322/// symbolicAddressesAreRIPRel - Return true if symbolic addresses are
323/// RIP-relative on this machine, taking into consideration the relocation
324/// model and subtarget. RIP-relative addresses cannot have a separate
325/// base or index register.
326bool X86TargetMachine::symbolicAddressesAreRIPRel() const {
327  return getRelocationModel() != Reloc::Static &&
328         Subtarget.isPICStyleRIPRel();
329}
330