X86TargetMachine.cpp revision 198090 
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,
26                                                const StringRef &TT) {
27  Triple TheTriple(TT);
28  switch (TheTriple.getOS()) {
29  case Triple::Darwin:
30    return new X86MCAsmInfoDarwin(TheTriple);
31  case Triple::MinGW32:
32  case Triple::MinGW64:
33  case Triple::Cygwin:
34    return new X86MCAsmInfoCOFF(TheTriple);
35  case Triple::Win32:
36    return new X86WinMCAsmInfo(TheTriple);
37  default:
38    return new X86ELFMCAsmInfo(TheTriple);
39  }
40}
41
42extern "C" void LLVMInitializeX86Target() {
43  // Register the target.
44  RegisterTargetMachine<X86_32TargetMachine> X(TheX86_32Target);
45  RegisterTargetMachine<X86_64TargetMachine> Y(TheX86_64Target);
46
47  // Register the target asm info.
48  RegisterAsmInfoFn A(TheX86_32Target, createMCAsmInfo);
49  RegisterAsmInfoFn B(TheX86_64Target, createMCAsmInfo);
50
51  // Register the code emitter.
52  TargetRegistry::RegisterCodeEmitter(TheX86_32Target, createX86MCCodeEmitter);
53  TargetRegistry::RegisterCodeEmitter(TheX86_64Target, createX86MCCodeEmitter);
54}
55
56
57X86_32TargetMachine::X86_32TargetMachine(const Target &T, const std::string &TT,
58                                         const std::string &FS)
59  : X86TargetMachine(T, TT, FS, false) {
60}
61
62
63X86_64TargetMachine::X86_64TargetMachine(const Target &T, const std::string &TT,
64                                         const std::string &FS)
65  : X86TargetMachine(T, TT, FS, true) {
66}
67
68/// X86TargetMachine ctor - Create an X86 target.
69///
70X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
71                                   const std::string &FS, bool is64Bit)
72  : LLVMTargetMachine(T, TT),
73    Subtarget(TT, FS, is64Bit),
74    DataLayout(Subtarget.getDataLayout()),
75    FrameInfo(TargetFrameInfo::StackGrowsDown,
76              Subtarget.getStackAlignment(),
77              (Subtarget.isTargetWin64() ? -40 :
78               (Subtarget.is64Bit() ? -8 : -4))),
79    InstrInfo(*this), JITInfo(*this), TLInfo(*this), ELFWriterInfo(*this) {
80  DefRelocModel = getRelocationModel();
81
82  // If no relocation model was picked, default as appropriate for the target.
83  if (getRelocationModel() == Reloc::Default) {
84    if (!Subtarget.isTargetDarwin())
85      setRelocationModel(Reloc::Static);
86    else if (Subtarget.is64Bit())
87      setRelocationModel(Reloc::PIC_);
88    else
89      setRelocationModel(Reloc::DynamicNoPIC);
90  }
91
92  assert(getRelocationModel() != Reloc::Default &&
93         "Relocation mode not picked");
94
95  // If no code model is picked, default to small.
96  if (getCodeModel() == CodeModel::Default)
97    setCodeModel(CodeModel::Small);
98
99  // ELF and X86-64 don't have a distinct DynamicNoPIC model.  DynamicNoPIC
100  // is defined as a model for code which may be used in static or dynamic
101  // executables but not necessarily a shared library. On X86-32 we just
102  // compile in -static mode, in x86-64 we use PIC.
103  if (getRelocationModel() == Reloc::DynamicNoPIC) {
104    if (is64Bit)
105      setRelocationModel(Reloc::PIC_);
106    else if (!Subtarget.isTargetDarwin())
107      setRelocationModel(Reloc::Static);
108  }
109
110  // If we are on Darwin, disallow static relocation model in X86-64 mode, since
111  // the Mach-O file format doesn't support it.
112  if (getRelocationModel() == Reloc::Static &&
113      Subtarget.isTargetDarwin() &&
114      is64Bit)
115    setRelocationModel(Reloc::PIC_);
116
117  // Determine the PICStyle based on the target selected.
118  if (getRelocationModel() == Reloc::Static) {
119    // Unless we're in PIC or DynamicNoPIC mode, set the PIC style to None.
120    Subtarget.setPICStyle(PICStyles::None);
121  } else if (Subtarget.isTargetCygMing()) {
122    Subtarget.setPICStyle(PICStyles::None);
123  } else if (Subtarget.isTargetDarwin()) {
124    if (Subtarget.is64Bit())
125      Subtarget.setPICStyle(PICStyles::RIPRel);
126    else if (getRelocationModel() == Reloc::PIC_)
127      Subtarget.setPICStyle(PICStyles::StubPIC);
128    else {
129      assert(getRelocationModel() == Reloc::DynamicNoPIC);
130      Subtarget.setPICStyle(PICStyles::StubDynamicNoPIC);
131    }
132  } else if (Subtarget.isTargetELF()) {
133    if (Subtarget.is64Bit())
134      Subtarget.setPICStyle(PICStyles::RIPRel);
135    else
136      Subtarget.setPICStyle(PICStyles::GOT);
137  }
138
139  // Finally, if we have "none" as our PIC style, force to static mode.
140  if (Subtarget.getPICStyle() == PICStyles::None)
141    setRelocationModel(Reloc::Static);
142}
143
144//===----------------------------------------------------------------------===//
145// Pass Pipeline Configuration
146//===----------------------------------------------------------------------===//
147
148bool X86TargetMachine::addInstSelector(PassManagerBase &PM,
149                                       CodeGenOpt::Level OptLevel) {
150  // Install an instruction selector.
151  PM.add(createX86ISelDag(*this, OptLevel));
152
153  // If we're using Fast-ISel, clean up the mess.
154  if (EnableFastISel)
155    PM.add(createDeadMachineInstructionElimPass());
156
157  // Install a pass to insert x87 FP_REG_KILL instructions, as needed.
158  PM.add(createX87FPRegKillInserterPass());
159
160  return false;
161}
162
163bool X86TargetMachine::addPreRegAlloc(PassManagerBase &PM,
164                                      CodeGenOpt::Level OptLevel) {
165  // Calculate and set max stack object alignment early, so we can decide
166  // whether we will need stack realignment (and thus FP).
167  PM.add(createX86MaxStackAlignmentCalculatorPass());
168  return false;  // -print-machineinstr shouldn't print after this.
169}
170
171bool X86TargetMachine::addPostRegAlloc(PassManagerBase &PM,
172                                       CodeGenOpt::Level OptLevel) {
173  PM.add(createX86FloatingPointStackifierPass());
174  return true;  // -print-machineinstr should print after this.
175}
176
177bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
178                                      CodeGenOpt::Level OptLevel,
179                                      MachineCodeEmitter &MCE) {
180  // FIXME: Move this to TargetJITInfo!
181  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
182  if (DefRelocModel == Reloc::Default &&
183      (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
184    setRelocationModel(Reloc::Static);
185    Subtarget.setPICStyle(PICStyles::None);
186  }
187
188  // 64-bit JIT places everything in the same buffer except external functions.
189  // On Darwin, use small code model but hack the call instruction for
190  // externals.  Elsewhere, do not assume globals are in the lower 4G.
191  if (Subtarget.is64Bit()) {
192    if (Subtarget.isTargetDarwin())
193      setCodeModel(CodeModel::Small);
194    else
195      setCodeModel(CodeModel::Large);
196  }
197
198  PM.add(createX86CodeEmitterPass(*this, MCE));
199
200  return false;
201}
202
203bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
204                                      CodeGenOpt::Level OptLevel,
205                                      JITCodeEmitter &JCE) {
206  // FIXME: Move this to TargetJITInfo!
207  // On Darwin, do not override 64-bit setting made in X86TargetMachine().
208  if (DefRelocModel == Reloc::Default &&
209      (!Subtarget.isTargetDarwin() || !Subtarget.is64Bit())) {
210    setRelocationModel(Reloc::Static);
211    Subtarget.setPICStyle(PICStyles::None);
212  }
213
214  // 64-bit JIT places everything in the same buffer except external functions.
215  // On Darwin, use small code model but hack the call instruction for
216  // externals.  Elsewhere, do not assume globals are in the lower 4G.
217  if (Subtarget.is64Bit()) {
218    if (Subtarget.isTargetDarwin())
219      setCodeModel(CodeModel::Small);
220    else
221      setCodeModel(CodeModel::Large);
222  }
223
224  PM.add(createX86JITCodeEmitterPass(*this, JCE));
225
226  return false;
227}
228
229bool X86TargetMachine::addCodeEmitter(PassManagerBase &PM,
230                                      CodeGenOpt::Level OptLevel,
231                                      ObjectCodeEmitter &OCE) {
232  PM.add(createX86ObjectCodeEmitterPass(*this, OCE));
233  return false;
234}
235
236bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
237                                            CodeGenOpt::Level OptLevel,
238                                            MachineCodeEmitter &MCE) {
239  PM.add(createX86CodeEmitterPass(*this, MCE));
240  return false;
241}
242
243bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
244                                            CodeGenOpt::Level OptLevel,
245                                            JITCodeEmitter &JCE) {
246  PM.add(createX86JITCodeEmitterPass(*this, JCE));
247  return false;
248}
249
250bool X86TargetMachine::addSimpleCodeEmitter(PassManagerBase &PM,
251                                            CodeGenOpt::Level OptLevel,
252                                            ObjectCodeEmitter &OCE) {
253  PM.add(createX86ObjectCodeEmitterPass(*this, OCE));
254  return false;
255}
256