MachineFunction.cpp revision f1d015f3429f611c423f943c75f86e6823810dc3 
1//===-- MachineFunction.cpp -----------------------------------------------===//
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// Collect native machine code information for a function.  This allows
11// target-specific information about the generated code to be stored with each
12// function.
13//
14//===----------------------------------------------------------------------===//
15
16#include "llvm/CodeGen/MachineFunction.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/SmallString.h"
19#include "llvm/Analysis/ConstantFolding.h"
20#include "llvm/CodeGen/MachineConstantPool.h"
21#include "llvm/CodeGen/MachineFrameInfo.h"
22#include "llvm/CodeGen/MachineFunctionPass.h"
23#include "llvm/CodeGen/MachineInstr.h"
24#include "llvm/CodeGen/MachineJumpTableInfo.h"
25#include "llvm/CodeGen/MachineModuleInfo.h"
26#include "llvm/CodeGen/MachineRegisterInfo.h"
27#include "llvm/CodeGen/Passes.h"
28#include "llvm/DebugInfo.h"
29#include "llvm/IR/DataLayout.h"
30#include "llvm/IR/Function.h"
31#include "llvm/MC/MCAsmInfo.h"
32#include "llvm/MC/MCContext.h"
33#include "llvm/Support/Debug.h"
34#include "llvm/Support/GraphWriter.h"
35#include "llvm/Support/raw_ostream.h"
36#include "llvm/Target/TargetFrameLowering.h"
37#include "llvm/Target/TargetLowering.h"
38#include "llvm/Target/TargetMachine.h"
39using namespace llvm;
40
41//===----------------------------------------------------------------------===//
42// MachineFunction implementation
43//===----------------------------------------------------------------------===//
44
45// Out of line virtual method.
46MachineFunctionInfo::~MachineFunctionInfo() {}
47
48void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) {
49  MBB->getParent()->DeleteMachineBasicBlock(MBB);
50}
51
52MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM,
53                                 unsigned FunctionNum, MachineModuleInfo &mmi,
54                                 GCModuleInfo* gmi)
55  : Fn(F), Target(TM), Ctx(mmi.getContext()), MMI(mmi), GMI(gmi) {
56  if (TM.getRegisterInfo())
57    RegInfo = new (Allocator) MachineRegisterInfo(*TM.getRegisterInfo());
58  else
59    RegInfo = 0;
60  MFInfo = 0;
61  FrameInfo = new (Allocator) MachineFrameInfo(*TM.getFrameLowering(),
62                                               TM.Options.RealignStack);
63  if (Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
64                                       Attribute::StackAlignment))
65    FrameInfo->ensureMaxAlignment(Fn->getAttributes().
66                                getStackAlignment(AttributeSet::FunctionIndex));
67  ConstantPool = new (Allocator) MachineConstantPool(TM.getDataLayout());
68  Alignment = TM.getTargetLowering()->getMinFunctionAlignment();
69  // FIXME: Shouldn't use pref alignment if explicit alignment is set on Fn.
70  if (!Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
71                                        Attribute::OptimizeForSize))
72    Alignment = std::max(Alignment,
73                         TM.getTargetLowering()->getPrefFunctionAlignment());
74  FunctionNumber = FunctionNum;
75  JumpTableInfo = 0;
76}
77
78MachineFunction::~MachineFunction() {
79  BasicBlocks.clear();
80  InstructionRecycler.clear(Allocator);
81  OperandRecycler.clear(Allocator);
82  BasicBlockRecycler.clear(Allocator);
83  if (RegInfo) {
84    RegInfo->~MachineRegisterInfo();
85    Allocator.Deallocate(RegInfo);
86  }
87  if (MFInfo) {
88    MFInfo->~MachineFunctionInfo();
89    Allocator.Deallocate(MFInfo);
90  }
91
92  FrameInfo->~MachineFrameInfo();
93  Allocator.Deallocate(FrameInfo);
94
95  ConstantPool->~MachineConstantPool();
96  Allocator.Deallocate(ConstantPool);
97
98  if (JumpTableInfo) {
99    JumpTableInfo->~MachineJumpTableInfo();
100    Allocator.Deallocate(JumpTableInfo);
101  }
102}
103
104/// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it
105/// does already exist, allocate one.
106MachineJumpTableInfo *MachineFunction::
107getOrCreateJumpTableInfo(unsigned EntryKind) {
108  if (JumpTableInfo) return JumpTableInfo;
109
110  JumpTableInfo = new (Allocator)
111    MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind);
112  return JumpTableInfo;
113}
114
115/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and
116/// recomputes them.  This guarantees that the MBB numbers are sequential,
117/// dense, and match the ordering of the blocks within the function.  If a
118/// specific MachineBasicBlock is specified, only that block and those after
119/// it are renumbered.
120void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
121  if (empty()) { MBBNumbering.clear(); return; }
122  MachineFunction::iterator MBBI, E = end();
123  if (MBB == 0)
124    MBBI = begin();
125  else
126    MBBI = MBB;
127
128  // Figure out the block number this should have.
129  unsigned BlockNo = 0;
130  if (MBBI != begin())
131    BlockNo = prior(MBBI)->getNumber()+1;
132
133  for (; MBBI != E; ++MBBI, ++BlockNo) {
134    if (MBBI->getNumber() != (int)BlockNo) {
135      // Remove use of the old number.
136      if (MBBI->getNumber() != -1) {
137        assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
138               "MBB number mismatch!");
139        MBBNumbering[MBBI->getNumber()] = 0;
140      }
141
142      // If BlockNo is already taken, set that block's number to -1.
143      if (MBBNumbering[BlockNo])
144        MBBNumbering[BlockNo]->setNumber(-1);
145
146      MBBNumbering[BlockNo] = MBBI;
147      MBBI->setNumber(BlockNo);
148    }
149  }
150
151  // Okay, all the blocks are renumbered.  If we have compactified the block
152  // numbering, shrink MBBNumbering now.
153  assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
154  MBBNumbering.resize(BlockNo);
155}
156
157/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead
158/// of `new MachineInstr'.
159///
160MachineInstr *
161MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
162                                    DebugLoc DL, bool NoImp) {
163  return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
164    MachineInstr(*this, MCID, DL, NoImp);
165}
166
167/// CloneMachineInstr - Create a new MachineInstr which is a copy of the
168/// 'Orig' instruction, identical in all ways except the instruction
169/// has no parent, prev, or next.
170///
171MachineInstr *
172MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
173  return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
174             MachineInstr(*this, *Orig);
175}
176
177/// DeleteMachineInstr - Delete the given MachineInstr.
178///
179void
180MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
181  // Strip it for parts. The operand array and the MI object itself are
182  // independently recyclable.
183  if (MI->Operands)
184    deallocateOperandArray(MI->CapOperands, MI->Operands);
185  MI->Operands = 0;
186  MI->NumOperands = 0;
187  MI->~MachineInstr();
188  InstructionRecycler.Deallocate(Allocator, MI);
189}
190
191/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this
192/// instead of `new MachineBasicBlock'.
193///
194MachineBasicBlock *
195MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) {
196  return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
197             MachineBasicBlock(*this, bb);
198}
199
200/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock.
201///
202void
203MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
204  assert(MBB->getParent() == this && "MBB parent mismatch!");
205  MBB->~MachineBasicBlock();
206  BasicBlockRecycler.Deallocate(Allocator, MBB);
207}
208
209MachineMemOperand *
210MachineFunction::getMachineMemOperand(MachinePointerInfo PtrInfo, unsigned f,
211                                      uint64_t s, unsigned base_alignment,
212                                      const MDNode *TBAAInfo,
213                                      const MDNode *Ranges) {
214  return new (Allocator) MachineMemOperand(PtrInfo, f, s, base_alignment,
215                                           TBAAInfo, Ranges);
216}
217
218MachineMemOperand *
219MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
220                                      int64_t Offset, uint64_t Size) {
221  return new (Allocator)
222             MachineMemOperand(MachinePointerInfo(MMO->getValue(),
223                                                  MMO->getOffset()+Offset),
224                               MMO->getFlags(), Size,
225                               MMO->getBaseAlignment(), 0);
226}
227
228MachineInstr::mmo_iterator
229MachineFunction::allocateMemRefsArray(unsigned long Num) {
230  return Allocator.Allocate<MachineMemOperand *>(Num);
231}
232
233std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
234MachineFunction::extractLoadMemRefs(MachineInstr::mmo_iterator Begin,
235                                    MachineInstr::mmo_iterator End) {
236  // Count the number of load mem refs.
237  unsigned Num = 0;
238  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
239    if ((*I)->isLoad())
240      ++Num;
241
242  // Allocate a new array and populate it with the load information.
243  MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
244  unsigned Index = 0;
245  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
246    if ((*I)->isLoad()) {
247      if (!(*I)->isStore())
248        // Reuse the MMO.
249        Result[Index] = *I;
250      else {
251        // Clone the MMO and unset the store flag.
252        MachineMemOperand *JustLoad =
253          getMachineMemOperand((*I)->getPointerInfo(),
254                               (*I)->getFlags() & ~MachineMemOperand::MOStore,
255                               (*I)->getSize(), (*I)->getBaseAlignment(),
256                               (*I)->getTBAAInfo());
257        Result[Index] = JustLoad;
258      }
259      ++Index;
260    }
261  }
262  return std::make_pair(Result, Result + Num);
263}
264
265std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
266MachineFunction::extractStoreMemRefs(MachineInstr::mmo_iterator Begin,
267                                     MachineInstr::mmo_iterator End) {
268  // Count the number of load mem refs.
269  unsigned Num = 0;
270  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
271    if ((*I)->isStore())
272      ++Num;
273
274  // Allocate a new array and populate it with the store information.
275  MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
276  unsigned Index = 0;
277  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
278    if ((*I)->isStore()) {
279      if (!(*I)->isLoad())
280        // Reuse the MMO.
281        Result[Index] = *I;
282      else {
283        // Clone the MMO and unset the load flag.
284        MachineMemOperand *JustStore =
285          getMachineMemOperand((*I)->getPointerInfo(),
286                               (*I)->getFlags() & ~MachineMemOperand::MOLoad,
287                               (*I)->getSize(), (*I)->getBaseAlignment(),
288                               (*I)->getTBAAInfo());
289        Result[Index] = JustStore;
290      }
291      ++Index;
292    }
293  }
294  return std::make_pair(Result, Result + Num);
295}
296
297#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
298void MachineFunction::dump() const {
299  print(dbgs());
300}
301#endif
302
303StringRef MachineFunction::getName() const {
304  assert(getFunction() && "No function!");
305  return getFunction()->getName();
306}
307
308void MachineFunction::print(raw_ostream &OS, SlotIndexes *Indexes) const {
309  OS << "# Machine code for function " << getName() << ": ";
310  if (RegInfo) {
311    OS << (RegInfo->isSSA() ? "SSA" : "Post SSA");
312    if (!RegInfo->tracksLiveness())
313      OS << ", not tracking liveness";
314  }
315  OS << '\n';
316
317  // Print Frame Information
318  FrameInfo->print(*this, OS);
319
320  // Print JumpTable Information
321  if (JumpTableInfo)
322    JumpTableInfo->print(OS);
323
324  // Print Constant Pool
325  ConstantPool->print(OS);
326
327  const TargetRegisterInfo *TRI = getTarget().getRegisterInfo();
328
329  if (RegInfo && !RegInfo->livein_empty()) {
330    OS << "Function Live Ins: ";
331    for (MachineRegisterInfo::livein_iterator
332         I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
333      OS << PrintReg(I->first, TRI);
334      if (I->second)
335        OS << " in " << PrintReg(I->second, TRI);
336      if (llvm::next(I) != E)
337        OS << ", ";
338    }
339    OS << '\n';
340  }
341  if (RegInfo && !RegInfo->liveout_empty()) {
342    OS << "Function Live Outs:";
343    for (MachineRegisterInfo::liveout_iterator
344         I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I)
345      OS << ' ' << PrintReg(*I, TRI);
346    OS << '\n';
347  }
348
349  for (const_iterator BB = begin(), E = end(); BB != E; ++BB) {
350    OS << '\n';
351    BB->print(OS, Indexes);
352  }
353
354  OS << "\n# End machine code for function " << getName() << ".\n\n";
355}
356
357namespace llvm {
358  template<>
359  struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
360
361  DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
362
363    static std::string getGraphName(const MachineFunction *F) {
364      return "CFG for '" + F->getName().str() + "' function";
365    }
366
367    std::string getNodeLabel(const MachineBasicBlock *Node,
368                             const MachineFunction *Graph) {
369      std::string OutStr;
370      {
371        raw_string_ostream OSS(OutStr);
372
373        if (isSimple()) {
374          OSS << "BB#" << Node->getNumber();
375          if (const BasicBlock *BB = Node->getBasicBlock())
376            OSS << ": " << BB->getName();
377        } else
378          Node->print(OSS);
379      }
380
381      if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
382
383      // Process string output to make it nicer...
384      for (unsigned i = 0; i != OutStr.length(); ++i)
385        if (OutStr[i] == '\n') {                            // Left justify
386          OutStr[i] = '\\';
387          OutStr.insert(OutStr.begin()+i+1, 'l');
388        }
389      return OutStr;
390    }
391  };
392}
393
394void MachineFunction::viewCFG() const
395{
396#ifndef NDEBUG
397  ViewGraph(this, "mf" + getName());
398#else
399  errs() << "MachineFunction::viewCFG is only available in debug builds on "
400         << "systems with Graphviz or gv!\n";
401#endif // NDEBUG
402}
403
404void MachineFunction::viewCFGOnly() const
405{
406#ifndef NDEBUG
407  ViewGraph(this, "mf" + getName(), true);
408#else
409  errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
410         << "systems with Graphviz or gv!\n";
411#endif // NDEBUG
412}
413
414/// addLiveIn - Add the specified physical register as a live-in value and
415/// create a corresponding virtual register for it.
416unsigned MachineFunction::addLiveIn(unsigned PReg,
417                                    const TargetRegisterClass *RC) {
418  MachineRegisterInfo &MRI = getRegInfo();
419  unsigned VReg = MRI.getLiveInVirtReg(PReg);
420  if (VReg) {
421    assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!");
422    return VReg;
423  }
424  VReg = MRI.createVirtualRegister(RC);
425  MRI.addLiveIn(PReg, VReg);
426  return VReg;
427}
428
429/// getJTISymbol - Return the MCSymbol for the specified non-empty jump table.
430/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
431/// normal 'L' label is returned.
432MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
433                                        bool isLinkerPrivate) const {
434  assert(JumpTableInfo && "No jump tables");
435  assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
436  const MCAsmInfo &MAI = *getTarget().getMCAsmInfo();
437
438  const char *Prefix = isLinkerPrivate ? MAI.getLinkerPrivateGlobalPrefix() :
439                                         MAI.getPrivateGlobalPrefix();
440  SmallString<60> Name;
441  raw_svector_ostream(Name)
442    << Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
443  return Ctx.GetOrCreateSymbol(Name.str());
444}
445
446/// getPICBaseSymbol - Return a function-local symbol to represent the PIC
447/// base.
448MCSymbol *MachineFunction::getPICBaseSymbol() const {
449  const MCAsmInfo &MAI = *Target.getMCAsmInfo();
450  return Ctx.GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix())+
451                               Twine(getFunctionNumber())+"$pb");
452}
453
454//===----------------------------------------------------------------------===//
455//  MachineFrameInfo implementation
456//===----------------------------------------------------------------------===//
457
458/// ensureMaxAlignment - Make sure the function is at least Align bytes
459/// aligned.
460void MachineFrameInfo::ensureMaxAlignment(unsigned Align) {
461  if (!TFI.isStackRealignable() || !RealignOption)
462    assert(Align <= TFI.getStackAlignment() &&
463           "For targets without stack realignment, Align is out of limit!");
464  if (MaxAlignment < Align) MaxAlignment = Align;
465}
466
467/// clampStackAlignment - Clamp the alignment if requested and emit a warning.
468static inline unsigned clampStackAlignment(bool ShouldClamp, unsigned Align,
469                                           unsigned StackAlign) {
470  if (!ShouldClamp || Align <= StackAlign)
471    return Align;
472  DEBUG(dbgs() << "Warning: requested alignment " << Align
473               << " exceeds the stack alignment " << StackAlign
474               << " when stack realignment is off" << '\n');
475  return StackAlign;
476}
477
478/// CreateStackObject - Create a new statically sized stack object, returning
479/// a nonnegative identifier to represent it.
480///
481int MachineFrameInfo::CreateStackObject(uint64_t Size, unsigned Alignment,
482                      bool isSS, bool MayNeedSP, const AllocaInst *Alloca) {
483  assert(Size != 0 && "Cannot allocate zero size stack objects!");
484  Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
485                                  Alignment, TFI.getStackAlignment());
486  Objects.push_back(StackObject(Size, Alignment, 0, false, isSS, MayNeedSP,
487                                Alloca));
488  int Index = (int)Objects.size() - NumFixedObjects - 1;
489  assert(Index >= 0 && "Bad frame index!");
490  ensureMaxAlignment(Alignment);
491  return Index;
492}
493
494/// CreateSpillStackObject - Create a new statically sized stack object that
495/// represents a spill slot, returning a nonnegative identifier to represent
496/// it.
497///
498int MachineFrameInfo::CreateSpillStackObject(uint64_t Size,
499                                             unsigned Alignment) {
500  Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
501                                  Alignment, TFI.getStackAlignment());
502  CreateStackObject(Size, Alignment, true, false);
503  int Index = (int)Objects.size() - NumFixedObjects - 1;
504  ensureMaxAlignment(Alignment);
505  return Index;
506}
507
508/// CreateVariableSizedObject - Notify the MachineFrameInfo object that a
509/// variable sized object has been created.  This must be created whenever a
510/// variable sized object is created, whether or not the index returned is
511/// actually used.
512///
513int MachineFrameInfo::CreateVariableSizedObject(unsigned Alignment) {
514  HasVarSizedObjects = true;
515  Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
516                                  Alignment, TFI.getStackAlignment());
517  Objects.push_back(StackObject(0, Alignment, 0, false, false, true, 0));
518  ensureMaxAlignment(Alignment);
519  return (int)Objects.size()-NumFixedObjects-1;
520}
521
522/// CreateFixedObject - Create a new object at a fixed location on the stack.
523/// All fixed objects should be created before other objects are created for
524/// efficiency. By default, fixed objects are immutable. This returns an
525/// index with a negative value.
526///
527int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset,
528                                        bool Immutable) {
529  assert(Size != 0 && "Cannot allocate zero size fixed stack objects!");
530  // The alignment of the frame index can be determined from its offset from
531  // the incoming frame position.  If the frame object is at offset 32 and
532  // the stack is guaranteed to be 16-byte aligned, then we know that the
533  // object is 16-byte aligned.
534  unsigned StackAlign = TFI.getStackAlignment();
535  unsigned Align = MinAlign(SPOffset, StackAlign);
536  Align = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
537                              Align, TFI.getStackAlignment());
538  Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable,
539                                              /*isSS*/   false,
540                                              /*NeedSP*/ false,
541                                              /*Alloca*/ 0));
542  return -++NumFixedObjects;
543}
544
545
546BitVector
547MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const {
548  assert(MBB && "MBB must be valid");
549  const MachineFunction *MF = MBB->getParent();
550  assert(MF && "MBB must be part of a MachineFunction");
551  const TargetMachine &TM = MF->getTarget();
552  const TargetRegisterInfo *TRI = TM.getRegisterInfo();
553  BitVector BV(TRI->getNumRegs());
554
555  // Before CSI is calculated, no registers are considered pristine. They can be
556  // freely used and PEI will make sure they are saved.
557  if (!isCalleeSavedInfoValid())
558    return BV;
559
560  for (const uint16_t *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR)
561    BV.set(*CSR);
562
563  // The entry MBB always has all CSRs pristine.
564  if (MBB == &MF->front())
565    return BV;
566
567  // On other MBBs the saved CSRs are not pristine.
568  const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo();
569  for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
570         E = CSI.end(); I != E; ++I)
571    BV.reset(I->getReg());
572
573  return BV;
574}
575
576
577void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{
578  if (Objects.empty()) return;
579
580  const TargetFrameLowering *FI = MF.getTarget().getFrameLowering();
581  int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
582
583  OS << "Frame Objects:\n";
584
585  for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
586    const StackObject &SO = Objects[i];
587    OS << "  fi#" << (int)(i-NumFixedObjects) << ": ";
588    if (SO.Size == ~0ULL) {
589      OS << "dead\n";
590      continue;
591    }
592    if (SO.Size == 0)
593      OS << "variable sized";
594    else
595      OS << "size=" << SO.Size;
596    OS << ", align=" << SO.Alignment;
597
598    if (i < NumFixedObjects)
599      OS << ", fixed";
600    if (i < NumFixedObjects || SO.SPOffset != -1) {
601      int64_t Off = SO.SPOffset - ValOffset;
602      OS << ", at location [SP";
603      if (Off > 0)
604        OS << "+" << Off;
605      else if (Off < 0)
606        OS << Off;
607      OS << "]";
608    }
609    OS << "\n";
610  }
611}
612
613#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
614void MachineFrameInfo::dump(const MachineFunction &MF) const {
615  print(MF, dbgs());
616}
617#endif
618
619//===----------------------------------------------------------------------===//
620//  MachineJumpTableInfo implementation
621//===----------------------------------------------------------------------===//
622
623/// getEntrySize - Return the size of each entry in the jump table.
624unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
625  // The size of a jump table entry is 4 bytes unless the entry is just the
626  // address of a block, in which case it is the pointer size.
627  switch (getEntryKind()) {
628  case MachineJumpTableInfo::EK_BlockAddress:
629    return TD.getPointerSize();
630  case MachineJumpTableInfo::EK_GPRel64BlockAddress:
631    return 8;
632  case MachineJumpTableInfo::EK_GPRel32BlockAddress:
633  case MachineJumpTableInfo::EK_LabelDifference32:
634  case MachineJumpTableInfo::EK_Custom32:
635    return 4;
636  case MachineJumpTableInfo::EK_Inline:
637    return 0;
638  }
639  llvm_unreachable("Unknown jump table encoding!");
640}
641
642/// getEntryAlignment - Return the alignment of each entry in the jump table.
643unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
644  // The alignment of a jump table entry is the alignment of int32 unless the
645  // entry is just the address of a block, in which case it is the pointer
646  // alignment.
647  switch (getEntryKind()) {
648  case MachineJumpTableInfo::EK_BlockAddress:
649    return TD.getPointerABIAlignment();
650  case MachineJumpTableInfo::EK_GPRel64BlockAddress:
651    return TD.getABIIntegerTypeAlignment(64);
652  case MachineJumpTableInfo::EK_GPRel32BlockAddress:
653  case MachineJumpTableInfo::EK_LabelDifference32:
654  case MachineJumpTableInfo::EK_Custom32:
655    return TD.getABIIntegerTypeAlignment(32);
656  case MachineJumpTableInfo::EK_Inline:
657    return 1;
658  }
659  llvm_unreachable("Unknown jump table encoding!");
660}
661
662/// createJumpTableIndex - Create a new jump table entry in the jump table info.
663///
664unsigned MachineJumpTableInfo::createJumpTableIndex(
665                               const std::vector<MachineBasicBlock*> &DestBBs) {
666  assert(!DestBBs.empty() && "Cannot create an empty jump table!");
667  JumpTables.push_back(MachineJumpTableEntry(DestBBs));
668  return JumpTables.size()-1;
669}
670
671/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update
672/// the jump tables to branch to New instead.
673bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
674                                                  MachineBasicBlock *New) {
675  assert(Old != New && "Not making a change?");
676  bool MadeChange = false;
677  for (size_t i = 0, e = JumpTables.size(); i != e; ++i)
678    ReplaceMBBInJumpTable(i, Old, New);
679  return MadeChange;
680}
681
682/// ReplaceMBBInJumpTable - If Old is a target of the jump tables, update
683/// the jump table to branch to New instead.
684bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
685                                                 MachineBasicBlock *Old,
686                                                 MachineBasicBlock *New) {
687  assert(Old != New && "Not making a change?");
688  bool MadeChange = false;
689  MachineJumpTableEntry &JTE = JumpTables[Idx];
690  for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j)
691    if (JTE.MBBs[j] == Old) {
692      JTE.MBBs[j] = New;
693      MadeChange = true;
694    }
695  return MadeChange;
696}
697
698void MachineJumpTableInfo::print(raw_ostream &OS) const {
699  if (JumpTables.empty()) return;
700
701  OS << "Jump Tables:\n";
702
703  for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
704    OS << "  jt#" << i << ": ";
705    for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j)
706      OS << " BB#" << JumpTables[i].MBBs[j]->getNumber();
707  }
708
709  OS << '\n';
710}
711
712#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
713void MachineJumpTableInfo::dump() const { print(dbgs()); }
714#endif
715
716
717//===----------------------------------------------------------------------===//
718//  MachineConstantPool implementation
719//===----------------------------------------------------------------------===//
720
721void MachineConstantPoolValue::anchor() { }
722
723Type *MachineConstantPoolEntry::getType() const {
724  if (isMachineConstantPoolEntry())
725    return Val.MachineCPVal->getType();
726  return Val.ConstVal->getType();
727}
728
729
730unsigned MachineConstantPoolEntry::getRelocationInfo() const {
731  if (isMachineConstantPoolEntry())
732    return Val.MachineCPVal->getRelocationInfo();
733  return Val.ConstVal->getRelocationInfo();
734}
735
736MachineConstantPool::~MachineConstantPool() {
737  for (unsigned i = 0, e = Constants.size(); i != e; ++i)
738    if (Constants[i].isMachineConstantPoolEntry())
739      delete Constants[i].Val.MachineCPVal;
740  for (DenseSet<MachineConstantPoolValue*>::iterator I =
741       MachineCPVsSharingEntries.begin(), E = MachineCPVsSharingEntries.end();
742       I != E; ++I)
743    delete *I;
744}
745
746/// CanShareConstantPoolEntry - Test whether the given two constants
747/// can be allocated the same constant pool entry.
748static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
749                                      const DataLayout *TD) {
750  // Handle the trivial case quickly.
751  if (A == B) return true;
752
753  // If they have the same type but weren't the same constant, quickly
754  // reject them.
755  if (A->getType() == B->getType()) return false;
756
757  // We can't handle structs or arrays.
758  if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) ||
759      isa<StructType>(B->getType()) || isa<ArrayType>(B->getType()))
760    return false;
761
762  // For now, only support constants with the same size.
763  uint64_t StoreSize = TD->getTypeStoreSize(A->getType());
764  if (StoreSize != TD->getTypeStoreSize(B->getType()) ||
765      StoreSize > 128)
766    return false;
767
768  Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8);
769
770  // Try constant folding a bitcast of both instructions to an integer.  If we
771  // get two identical ConstantInt's, then we are good to share them.  We use
772  // the constant folding APIs to do this so that we get the benefit of
773  // DataLayout.
774  if (isa<PointerType>(A->getType()))
775    A = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy,
776                                 const_cast<Constant*>(A), TD);
777  else if (A->getType() != IntTy)
778    A = ConstantFoldInstOperands(Instruction::BitCast, IntTy,
779                                 const_cast<Constant*>(A), TD);
780  if (isa<PointerType>(B->getType()))
781    B = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy,
782                                 const_cast<Constant*>(B), TD);
783  else if (B->getType() != IntTy)
784    B = ConstantFoldInstOperands(Instruction::BitCast, IntTy,
785                                 const_cast<Constant*>(B), TD);
786
787  return A == B;
788}
789
790/// getConstantPoolIndex - Create a new entry in the constant pool or return
791/// an existing one.  User must specify the log2 of the minimum required
792/// alignment for the object.
793///
794unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
795                                                   unsigned Alignment) {
796  assert(Alignment && "Alignment must be specified!");
797  if (Alignment > PoolAlignment) PoolAlignment = Alignment;
798
799  // Check to see if we already have this constant.
800  //
801  // FIXME, this could be made much more efficient for large constant pools.
802  for (unsigned i = 0, e = Constants.size(); i != e; ++i)
803    if (!Constants[i].isMachineConstantPoolEntry() &&
804        CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, TD)) {
805      if ((unsigned)Constants[i].getAlignment() < Alignment)
806        Constants[i].Alignment = Alignment;
807      return i;
808    }
809
810  Constants.push_back(MachineConstantPoolEntry(C, Alignment));
811  return Constants.size()-1;
812}
813
814unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
815                                                   unsigned Alignment) {
816  assert(Alignment && "Alignment must be specified!");
817  if (Alignment > PoolAlignment) PoolAlignment = Alignment;
818
819  // Check to see if we already have this constant.
820  //
821  // FIXME, this could be made much more efficient for large constant pools.
822  int Idx = V->getExistingMachineCPValue(this, Alignment);
823  if (Idx != -1) {
824    MachineCPVsSharingEntries.insert(V);
825    return (unsigned)Idx;
826  }
827
828  Constants.push_back(MachineConstantPoolEntry(V, Alignment));
829  return Constants.size()-1;
830}
831
832void MachineConstantPool::print(raw_ostream &OS) const {
833  if (Constants.empty()) return;
834
835  OS << "Constant Pool:\n";
836  for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
837    OS << "  cp#" << i << ": ";
838    if (Constants[i].isMachineConstantPoolEntry())
839      Constants[i].Val.MachineCPVal->print(OS);
840    else
841      OS << *(const Value*)Constants[i].Val.ConstVal;
842    OS << ", align=" << Constants[i].getAlignment();
843    OS << "\n";
844  }
845}
846
847#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
848void MachineConstantPool::dump() const { print(dbgs()); }
849#endif
850