X86TargetMachine.cpp revision 193574 
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// No assembler printer by default
40X86TargetMachine::AsmPrinterCtorFn X86TargetMachine::AsmPrinterCtor = 0;
41
42const TargetAsmInfo *X86TargetMachine::createTargetAsmInfo() const {
43  if (Subtarget.isFlavorIntel())
44    return new X86WinTargetAsmInfo(*this);
45  else
46    switch (Subtarget.TargetType) {
47     case X86Subtarget::isDarwin:
48      return new X86DarwinTargetAsmInfo(*this);
49     case X86Subtarget::isELF:
50      return new X86ELFTargetAsmInfo(*this);
51     case X86Subtarget::isMingw:
52     case X86Subtarget::isCygwin:
53      return new X86COFFTargetAsmInfo(*this);
54     case X86Subtarget::isWindows:
55      return new X86WinTargetAsmInfo(*this);
56     default:
57      return new X86GenericTargetAsmInfo(*this);
58    }
59}
60
61unsigned X86_32TargetMachine::getJITMatchQuality() {
62#if defined(i386) || defined(__i386__) || defined(__x86__) || defined(_M_IX86)
63  return 10;
64#endif
65  return 0;
66}
67
68unsigned X86_64TargetMachine::getJITMatchQuality() {
69#if defined(__x86_64__) || defined(_M_AMD64)
70  return 10;
71#endif
72  return 0;
73}
74
75unsigned X86_32TargetMachine::getModuleMatchQuality(const Module &M) {
76  // We strongly match "i[3-9]86-*".
77  std::string TT = M.getTargetTriple();
78  if (TT.size() >= 5 && TT[0] == 'i' && TT[2] == '8' && TT[3] == '6' &&
79      TT[4] == '-' && TT[1] - '3' < 6)
80    return 20;
81  // If the target triple is something non-X86, we don't match.
82  if (!TT.empty()) return 0;
83
84  if (M.getEndianness()  == Module::LittleEndian &&
85      M.getPointerSize() == Module::Pointer32)
86    return 10;                                   // Weak match
87  else if (M.getEndianness() != Module::AnyEndianness ||
88           M.getPointerSize() != Module::AnyPointerSize)
89    return 0;                                    // Match for some other target
90
91  return getJITMatchQuality()/2;
92}
93
94unsigned X86_64TargetMachine::getModuleMatchQuality(const Module &M) {
95  // We strongly match "x86_64-*".
96  std::string TT = M.getTargetTriple();
97  if (TT.size() >= 7 && TT[0] == 'x' && TT[1] == '8' && TT[2] == '6' &&
98      TT[3] == '_' && TT[4] == '6' && TT[5] == '4' && TT[6] == '-')
99    return 20;
100
101  // We strongly match "amd64-*".
102  if (TT.size() >= 6 && TT[0] == 'a' && TT[1] == 'm' && TT[2] == 'd' &&
103      TT[3] == '6' && TT[4] == '4' && TT[5] == '-')
104    return 20;
105
106  // If the target triple is something non-X86-64, we don't match.
107  if (!TT.empty()) return 0;
108
109  if (M.getEndianness()  == Module::LittleEndian &&
110      M.getPointerSize() == Module::Pointer64)
111    return 10;                                   // Weak match
112  else if (M.getEndianness() != Module::AnyEndianness ||
113           M.getPointerSize() != Module::AnyPointerSize)
114    return 0;                                    // Match for some other target
115
116  return getJITMatchQuality()/2;
117}
118
119X86_32TargetMachine::X86_32TargetMachine(const Module &M, const std::string &FS)
120  : X86TargetMachine(M, FS, false) {
121}
122
123
124X86_64TargetMachine::X86_64TargetMachine(const Module &M, const std::string &FS)
125  : X86TargetMachine(M, FS, true) {
126}
127
128/// X86TargetMachine ctor - Create an ILP32 architecture model
129///
130X86TargetMachine::X86TargetMachine(const Module &M, const std::string &FS,
131                                   bool is64Bit)
132  : Subtarget(M, FS, is64Bit),
133    DataLayout(Subtarget.getDataLayout()),
134    FrameInfo(TargetFrameInfo::StackGrowsDown,
135              Subtarget.getStackAlignment(), Subtarget.is64Bit() ? -8 : -4),
136    InstrInfo(*this), JITInfo(*this), TLInfo(*this),
137    ELFWriterInfo(Subtarget.is64Bit()) {
138  DefRelocModel = getRelocationModel();
139  // FIXME: Correctly select PIC model for Win64 stuff
140  if (getRelocationModel() == Reloc::Default) {
141    if (Subtarget.isTargetDarwin() ||
142        (Subtarget.isTargetCygMing() && !Subtarget.isTargetWin64()))
143      setRelocationModel(Reloc::DynamicNoPIC);
144    else
145      setRelocationModel(Reloc::Static);
146  }
147
148  // ELF doesn't have a distinct dynamic-no-PIC model. Dynamic-no-PIC
149  // is defined as a model for code which may be used in static or
150  // dynamic executables but not necessarily a shared library. On ELF
151  // implement this by using the Static model.
152  if (Subtarget.isTargetELF() &&
153      getRelocationModel() == Reloc::DynamicNoPIC)
154    setRelocationModel(Reloc::Static);
155
156  if (Subtarget.is64Bit()) {
157    // No DynamicNoPIC support under X86-64.
158    if (getRelocationModel() == Reloc::DynamicNoPIC)
159      setRelocationModel(Reloc::PIC_);
160    // Default X86-64 code model is small.
161    if (getCodeModel() == CodeModel::Default)
162      setCodeModel(CodeModel::Small);
163  }
164
165  if (Subtarget.isTargetCygMing())
166    Subtarget.setPICStyle(PICStyles::WinPIC);
167  else if (Subtarget.isTargetDarwin()) {
168    if (Subtarget.is64Bit())
169      Subtarget.setPICStyle(PICStyles::RIPRel);
170    else
171      Subtarget.setPICStyle(PICStyles::Stub);
172  } else if (Subtarget.isTargetELF()) {
173    if (Subtarget.is64Bit())
174      Subtarget.setPICStyle(PICStyles::RIPRel);
175    else
176      Subtarget.setPICStyle(PICStyles::GOT);
177  }
178}
179
180//===----------------------------------------------------------------------===//
181// Pass Pipeline Configuration
182//===----------------------------------------------------------------------===//
183
184bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
185                                       CodeGenOpt::Level OptLevel) {
186  // Install an instruction selector.
187  PM.add(createX86ISelDag(*this, OptLevel));
188
189  // If we're using Fast-ISel, clean up the mess.
190  if (EnableFastISel)
191    PM.add(createDeadMachineInstructionElimPass());
192
193  // Install a pass to insert x87 FP_REG_KILL instructions, as needed.
194  PM.add(createX87FPRegKillInserterPass());
195
196  return false;
197}
198
199bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
200                                      CodeGenOpt::Level OptLevel) {
201  // Calculate and set max stack object alignment early, so we can decide
202  // whether we will need stack realignment (and thus FP).
203  PM.add(createX86MaxStackAlignmentCalculatorPass());
204  return false;  // -print-machineinstr shouldn't print after this.
205}
206
207bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
208                                       CodeGenOpt::Level OptLevel) {
209  PM.add(createX86FloatingPointStackifierPass());
210  return true;  // -print-machineinstr should print after this.
211}
212
213bool X86TargetMachine::addAssemblyEmitter(PassManagerBase &PM,
214                                          CodeGenOpt::Level OptLevel,
215                                          bool Verbose,
216                                          raw_ostream &Out) {
217  // FIXME: Move this somewhere else!
218  // On Darwin, override 64-bit static relocation to pic_ since the
219  // assembler doesn't support it.
220  if (DefRelocModel == Reloc::Static &&
221      Subtarget.isTargetDarwin() && Subtarget.is64Bit())
222    setRelocationModel(Reloc::PIC_);
223
224  assert(AsmPrinterCtor && "AsmPrinter was not linked in");
225  if (AsmPrinterCtor)
226    PM.add(AsmPrinterCtor(Out, *this, OptLevel, Verbose));
227  return false;
228}
229
230bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
231                                      CodeGenOpt::Level OptLevel,
232                                      bool DumpAsm,
233                                      MachineCodeEmitter &MCE) {
234  // FIXME: Move this to TargetJITInfo!
235  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
236  if (DefRelocModel == Reloc::Default &&
237        (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit()))
238    setRelocationModel(Reloc::Static);
239
240  // 64-bit JIT places everything in the same buffer except external functions.
241  // On Darwin, use small code model but hack the call instruction for
242  // externals.  Elsewhere, do not assume globals are in the lower 4G.
243  if (Subtarget.is64Bit()) {
244    if (Subtarget.isTargetDarwin())
245      setCodeModel(CodeModel::Small);
246    else
247      setCodeModel(CodeModel::Large);
248  }
249
250  PM.add(createX86CodeEmitterPass(*this, MCE));
251  if (DumpAsm) {
252    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
253    if (AsmPrinterCtor)
254      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
255  }
256
257  return false;
258}
259
260bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
261                                      CodeGenOpt::Level OptLevel,
262                                      bool DumpAsm,
263                                      JITCodeEmitter &JCE) {
264  // FIXME: Move this to TargetJITInfo!
265  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
266  if (DefRelocModel == Reloc::Default &&
267        (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit()))
268    setRelocationModel(Reloc::Static);
269
270  // 64-bit JIT places everything in the same buffer except external functions.
271  // On Darwin, use small code model but hack the call instruction for
272  // externals.  Elsewhere, do not assume globals are in the lower 4G.
273  if (Subtarget.is64Bit()) {
274    if (Subtarget.isTargetDarwin())
275      setCodeModel(CodeModel::Small);
276    else
277      setCodeModel(CodeModel::Large);
278  }
279
280  PM.add(createX86JITCodeEmitterPass(*this, JCE));
281  if (DumpAsm) {
282    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
283    if (AsmPrinterCtor)
284      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
285  }
286
287  return false;
288}
289
290bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
291                                            CodeGenOpt::Level OptLevel,
292                                            bool DumpAsm,
293                                            MachineCodeEmitter &MCE) {
294  PM.add(createX86CodeEmitterPass(*this, MCE));
295  if (DumpAsm) {
296    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
297    if (AsmPrinterCtor)
298      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
299  }
300
301  return false;
302}
303
304bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
305                                            CodeGenOpt::Level OptLevel,
306                                            bool DumpAsm,
307                                            JITCodeEmitter &JCE) {
308  PM.add(createX86JITCodeEmitterPass(*this, JCE));
309  if (DumpAsm) {
310    assert(AsmPrinterCtor && "AsmPrinter was not linked in");
311    if (AsmPrinterCtor)
312      PM.add(AsmPrinterCtor(errs(), *this, OptLevel, true));
313  }
314
315  return false;
316}
317
318/// symbolicAddressesAreRIPRel - Return true if symbolic addresses are
319/// RIP-relative on this machine, taking into consideration the relocation
320/// model and subtarget. RIP-relative addresses cannot have a separate
321/// base or index register.
322bool X86TargetMachine::symbolicAddressesAreRIPRel() const {
323  return getRelocationModel() != Reloc::Static &&
324         Subtarget.isPICStyleRIPRel();
325}
326