MachineFunction.cpp revision b87d1b277c48489cae4fb53cdbb331e9d8f3fd81 
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/DerivedTypes.h"
17#include "llvm/Function.h"
18#include "llvm/Instructions.h"
19#include "llvm/Config/config.h"
20#include "llvm/CodeGen/MachineConstantPool.h"
21#include "llvm/CodeGen/MachineFunction.h"
22#include "llvm/CodeGen/MachineFunctionPass.h"
23#include "llvm/CodeGen/MachineFrameInfo.h"
24#include "llvm/CodeGen/MachineInstr.h"
25#include "llvm/CodeGen/MachineJumpTableInfo.h"
26#include "llvm/CodeGen/MachineModuleInfo.h"
27#include "llvm/CodeGen/MachineRegisterInfo.h"
28#include "llvm/CodeGen/Passes.h"
29#include "llvm/MC/MCAsmInfo.h"
30#include "llvm/MC/MCContext.h"
31#include "llvm/Analysis/DebugInfo.h"
32#include "llvm/Support/Debug.h"
33#include "llvm/Target/TargetData.h"
34#include "llvm/Target/TargetLowering.h"
35#include "llvm/Target/TargetMachine.h"
36#include "llvm/Target/TargetFrameInfo.h"
37#include "llvm/ADT/SmallString.h"
38#include "llvm/ADT/STLExtras.h"
39#include "llvm/Support/GraphWriter.h"
40#include "llvm/Support/raw_ostream.h"
41using namespace llvm;
42
43//===----------------------------------------------------------------------===//
44// MachineFunction implementation
45//===----------------------------------------------------------------------===//
46
47// Out of line virtual method.
48MachineFunctionInfo::~MachineFunctionInfo() {}
49
50void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) {
51  MBB->getParent()->DeleteMachineBasicBlock(MBB);
52}
53
54MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM,
55                                 unsigned FunctionNum, MachineModuleInfo &mmi)
56  : Fn(F), Target(TM), Ctx(mmi.getContext()), MMI(mmi) {
57  if (TM.getRegisterInfo())
58    RegInfo = new (Allocator) MachineRegisterInfo(*TM.getRegisterInfo());
59  else
60    RegInfo = 0;
61  MFInfo = 0;
62  FrameInfo = new (Allocator) MachineFrameInfo(*TM.getFrameInfo());
63  if (Fn->hasFnAttr(Attribute::StackAlignment))
64    FrameInfo->setMaxAlignment(Attribute::getStackAlignmentFromAttrs(
65        Fn->getAttributes().getFnAttributes()));
66  ConstantPool = new (Allocator) MachineConstantPool(TM.getTargetData());
67  Alignment = TM.getTargetLowering()->getFunctionAlignment(F);
68  FunctionNumber = FunctionNum;
69  JumpTableInfo = 0;
70}
71
72MachineFunction::~MachineFunction() {
73  BasicBlocks.clear();
74  InstructionRecycler.clear(Allocator);
75  BasicBlockRecycler.clear(Allocator);
76  if (RegInfo) {
77    RegInfo->~MachineRegisterInfo();
78    Allocator.Deallocate(RegInfo);
79  }
80  if (MFInfo) {
81    MFInfo->~MachineFunctionInfo();
82    Allocator.Deallocate(MFInfo);
83  }
84  FrameInfo->~MachineFrameInfo();         Allocator.Deallocate(FrameInfo);
85  ConstantPool->~MachineConstantPool();   Allocator.Deallocate(ConstantPool);
86
87  if (JumpTableInfo) {
88    JumpTableInfo->~MachineJumpTableInfo();
89    Allocator.Deallocate(JumpTableInfo);
90  }
91}
92
93/// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it
94/// does already exist, allocate one.
95MachineJumpTableInfo *MachineFunction::
96getOrCreateJumpTableInfo(unsigned EntryKind) {
97  if (JumpTableInfo) return JumpTableInfo;
98
99  JumpTableInfo = new (Allocator)
100    MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind);
101  return JumpTableInfo;
102}
103
104/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and
105/// recomputes them.  This guarantees that the MBB numbers are sequential,
106/// dense, and match the ordering of the blocks within the function.  If a
107/// specific MachineBasicBlock is specified, only that block and those after
108/// it are renumbered.
109void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
110  if (empty()) { MBBNumbering.clear(); return; }
111  MachineFunction::iterator MBBI, E = end();
112  if (MBB == 0)
113    MBBI = begin();
114  else
115    MBBI = MBB;
116
117  // Figure out the block number this should have.
118  unsigned BlockNo = 0;
119  if (MBBI != begin())
120    BlockNo = prior(MBBI)->getNumber()+1;
121
122  for (; MBBI != E; ++MBBI, ++BlockNo) {
123    if (MBBI->getNumber() != (int)BlockNo) {
124      // Remove use of the old number.
125      if (MBBI->getNumber() != -1) {
126        assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
127               "MBB number mismatch!");
128        MBBNumbering[MBBI->getNumber()] = 0;
129      }
130
131      // If BlockNo is already taken, set that block's number to -1.
132      if (MBBNumbering[BlockNo])
133        MBBNumbering[BlockNo]->setNumber(-1);
134
135      MBBNumbering[BlockNo] = MBBI;
136      MBBI->setNumber(BlockNo);
137    }
138  }
139
140  // Okay, all the blocks are renumbered.  If we have compactified the block
141  // numbering, shrink MBBNumbering now.
142  assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
143  MBBNumbering.resize(BlockNo);
144}
145
146/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead
147/// of `new MachineInstr'.
148///
149MachineInstr *
150MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID,
151                                    DebugLoc DL, bool NoImp) {
152  return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
153    MachineInstr(TID, DL, NoImp);
154}
155
156/// CloneMachineInstr - Create a new MachineInstr which is a copy of the
157/// 'Orig' instruction, identical in all ways except the instruction
158/// has no parent, prev, or next.
159///
160MachineInstr *
161MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
162  return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
163             MachineInstr(*this, *Orig);
164}
165
166/// DeleteMachineInstr - Delete the given MachineInstr.
167///
168void
169MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
170  MI->~MachineInstr();
171  InstructionRecycler.Deallocate(Allocator, MI);
172}
173
174/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this
175/// instead of `new MachineBasicBlock'.
176///
177MachineBasicBlock *
178MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) {
179  return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
180             MachineBasicBlock(*this, bb);
181}
182
183/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock.
184///
185void
186MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
187  assert(MBB->getParent() == this && "MBB parent mismatch!");
188  MBB->~MachineBasicBlock();
189  BasicBlockRecycler.Deallocate(Allocator, MBB);
190}
191
192MachineMemOperand *
193MachineFunction::getMachineMemOperand(MachinePointerInfo PtrInfo, unsigned f,
194                                      uint64_t s, unsigned base_alignment,
195                                      const MDNode *TBAAInfo) {
196  return new (Allocator) MachineMemOperand(PtrInfo, f, s, base_alignment,
197                                           TBAAInfo);
198}
199
200MachineMemOperand *
201MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
202                                      int64_t Offset, uint64_t Size) {
203  return new (Allocator)
204             MachineMemOperand(MachinePointerInfo(MMO->getValue(),
205                                                  MMO->getOffset()+Offset),
206                               MMO->getFlags(), Size,
207                               MMO->getBaseAlignment(), 0);
208}
209
210MachineInstr::mmo_iterator
211MachineFunction::allocateMemRefsArray(unsigned long Num) {
212  return Allocator.Allocate<MachineMemOperand *>(Num);
213}
214
215std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
216MachineFunction::extractLoadMemRefs(MachineInstr::mmo_iterator Begin,
217                                    MachineInstr::mmo_iterator End) {
218  // Count the number of load mem refs.
219  unsigned Num = 0;
220  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
221    if ((*I)->isLoad())
222      ++Num;
223
224  // Allocate a new array and populate it with the load information.
225  MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
226  unsigned Index = 0;
227  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
228    if ((*I)->isLoad()) {
229      if (!(*I)->isStore())
230        // Reuse the MMO.
231        Result[Index] = *I;
232      else {
233        // Clone the MMO and unset the store flag.
234        MachineMemOperand *JustLoad =
235          getMachineMemOperand((*I)->getPointerInfo(),
236                               (*I)->getFlags() & ~MachineMemOperand::MOStore,
237                               (*I)->getSize(), (*I)->getBaseAlignment(),
238                               (*I)->getTBAAInfo());
239        Result[Index] = JustLoad;
240      }
241      ++Index;
242    }
243  }
244  return std::make_pair(Result, Result + Num);
245}
246
247std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
248MachineFunction::extractStoreMemRefs(MachineInstr::mmo_iterator Begin,
249                                     MachineInstr::mmo_iterator End) {
250  // Count the number of load mem refs.
251  unsigned Num = 0;
252  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
253    if ((*I)->isStore())
254      ++Num;
255
256  // Allocate a new array and populate it with the store information.
257  MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
258  unsigned Index = 0;
259  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
260    if ((*I)->isStore()) {
261      if (!(*I)->isLoad())
262        // Reuse the MMO.
263        Result[Index] = *I;
264      else {
265        // Clone the MMO and unset the load flag.
266        MachineMemOperand *JustStore =
267          getMachineMemOperand((*I)->getPointerInfo(),
268                               (*I)->getFlags() & ~MachineMemOperand::MOLoad,
269                               (*I)->getSize(), (*I)->getBaseAlignment(),
270                               (*I)->getTBAAInfo());
271        Result[Index] = JustStore;
272      }
273      ++Index;
274    }
275  }
276  return std::make_pair(Result, Result + Num);
277}
278
279void MachineFunction::dump() const {
280  print(dbgs());
281}
282
283void MachineFunction::print(raw_ostream &OS, SlotIndexes *Indexes) const {
284  OS << "# Machine code for function " << Fn->getName() << ":\n";
285
286  // Print Frame Information
287  FrameInfo->print(*this, OS);
288
289  // Print JumpTable Information
290  if (JumpTableInfo)
291    JumpTableInfo->print(OS);
292
293  // Print Constant Pool
294  ConstantPool->print(OS);
295
296  const TargetRegisterInfo *TRI = getTarget().getRegisterInfo();
297
298  if (RegInfo && !RegInfo->livein_empty()) {
299    OS << "Function Live Ins: ";
300    for (MachineRegisterInfo::livein_iterator
301         I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
302      if (TRI)
303        OS << "%" << TRI->getName(I->first);
304      else
305        OS << " %physreg" << I->first;
306
307      if (I->second)
308        OS << " in reg%" << I->second;
309
310      if (llvm::next(I) != E)
311        OS << ", ";
312    }
313    OS << '\n';
314  }
315  if (RegInfo && !RegInfo->liveout_empty()) {
316    OS << "Function Live Outs: ";
317    for (MachineRegisterInfo::liveout_iterator
318         I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I){
319      if (TRI)
320        OS << '%' << TRI->getName(*I);
321      else
322        OS << "%physreg" << *I;
323
324      if (llvm::next(I) != E)
325        OS << " ";
326    }
327    OS << '\n';
328  }
329
330  for (const_iterator BB = begin(), E = end(); BB != E; ++BB) {
331    OS << '\n';
332    BB->print(OS, Indexes);
333  }
334
335  OS << "\n# End machine code for function " << Fn->getName() << ".\n\n";
336}
337
338namespace llvm {
339  template<>
340  struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
341
342  DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
343
344    static std::string getGraphName(const MachineFunction *F) {
345      return "CFG for '" + F->getFunction()->getNameStr() + "' function";
346    }
347
348    std::string getNodeLabel(const MachineBasicBlock *Node,
349                             const MachineFunction *Graph) {
350      if (isSimple () && Node->getBasicBlock() &&
351          !Node->getBasicBlock()->getName().empty())
352        return Node->getBasicBlock()->getNameStr() + ":";
353
354      std::string OutStr;
355      {
356        raw_string_ostream OSS(OutStr);
357
358        if (isSimple())
359          OSS << Node->getNumber() << ':';
360        else
361          Node->print(OSS);
362      }
363
364      if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
365
366      // Process string output to make it nicer...
367      for (unsigned i = 0; i != OutStr.length(); ++i)
368        if (OutStr[i] == '\n') {                            // Left justify
369          OutStr[i] = '\\';
370          OutStr.insert(OutStr.begin()+i+1, 'l');
371        }
372      return OutStr;
373    }
374  };
375}
376
377void MachineFunction::viewCFG() const
378{
379#ifndef NDEBUG
380  ViewGraph(this, "mf" + getFunction()->getNameStr());
381#else
382  errs() << "MachineFunction::viewCFG is only available in debug builds on "
383         << "systems with Graphviz or gv!\n";
384#endif // NDEBUG
385}
386
387void MachineFunction::viewCFGOnly() const
388{
389#ifndef NDEBUG
390  ViewGraph(this, "mf" + getFunction()->getNameStr(), true);
391#else
392  errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
393         << "systems with Graphviz or gv!\n";
394#endif // NDEBUG
395}
396
397/// addLiveIn - Add the specified physical register as a live-in value and
398/// create a corresponding virtual register for it.
399unsigned MachineFunction::addLiveIn(unsigned PReg,
400                                    const TargetRegisterClass *RC) {
401  MachineRegisterInfo &MRI = getRegInfo();
402  unsigned VReg = MRI.getLiveInVirtReg(PReg);
403  if (VReg) {
404    assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!");
405    return VReg;
406  }
407  VReg = MRI.createVirtualRegister(RC);
408  MRI.addLiveIn(PReg, VReg);
409  return VReg;
410}
411
412/// getJTISymbol - Return the MCSymbol for the specified non-empty jump table.
413/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
414/// normal 'L' label is returned.
415MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
416                                        bool isLinkerPrivate) const {
417  assert(JumpTableInfo && "No jump tables");
418
419  assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
420  const MCAsmInfo &MAI = *getTarget().getMCAsmInfo();
421
422  const char *Prefix = isLinkerPrivate ? MAI.getLinkerPrivateGlobalPrefix() :
423                                         MAI.getPrivateGlobalPrefix();
424  SmallString<60> Name;
425  raw_svector_ostream(Name)
426    << Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
427  return Ctx.GetOrCreateSymbol(Name.str());
428}
429
430
431//===----------------------------------------------------------------------===//
432//  MachineFrameInfo implementation
433//===----------------------------------------------------------------------===//
434
435/// CreateFixedObject - Create a new object at a fixed location on the stack.
436/// All fixed objects should be created before other objects are created for
437/// efficiency. By default, fixed objects are immutable. This returns an
438/// index with a negative value.
439///
440int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset,
441                                        bool Immutable) {
442  assert(Size != 0 && "Cannot allocate zero size fixed stack objects!");
443  // The alignment of the frame index can be determined from its offset from
444  // the incoming frame position.  If the frame object is at offset 32 and
445  // the stack is guaranteed to be 16-byte aligned, then we know that the
446  // object is 16-byte aligned.
447  unsigned StackAlign = TFI.getStackAlignment();
448  unsigned Align = MinAlign(SPOffset, StackAlign);
449  Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable,
450                                              /*isSS*/false, false));
451  return -++NumFixedObjects;
452}
453
454
455BitVector
456MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const {
457  assert(MBB && "MBB must be valid");
458  const MachineFunction *MF = MBB->getParent();
459  assert(MF && "MBB must be part of a MachineFunction");
460  const TargetMachine &TM = MF->getTarget();
461  const TargetRegisterInfo *TRI = TM.getRegisterInfo();
462  BitVector BV(TRI->getNumRegs());
463
464  // Before CSI is calculated, no registers are considered pristine. They can be
465  // freely used and PEI will make sure they are saved.
466  if (!isCalleeSavedInfoValid())
467    return BV;
468
469  for (const unsigned *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR)
470    BV.set(*CSR);
471
472  // The entry MBB always has all CSRs pristine.
473  if (MBB == &MF->front())
474    return BV;
475
476  // On other MBBs the saved CSRs are not pristine.
477  const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo();
478  for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
479         E = CSI.end(); I != E; ++I)
480    BV.reset(I->getReg());
481
482  return BV;
483}
484
485
486void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{
487  if (Objects.empty()) return;
488
489  const TargetFrameInfo *FI = MF.getTarget().getFrameInfo();
490  int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
491
492  OS << "Frame Objects:\n";
493
494  for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
495    const StackObject &SO = Objects[i];
496    OS << "  fi#" << (int)(i-NumFixedObjects) << ": ";
497    if (SO.Size == ~0ULL) {
498      OS << "dead\n";
499      continue;
500    }
501    if (SO.Size == 0)
502      OS << "variable sized";
503    else
504      OS << "size=" << SO.Size;
505    OS << ", align=" << SO.Alignment;
506
507    if (i < NumFixedObjects)
508      OS << ", fixed";
509    if (i < NumFixedObjects || SO.SPOffset != -1) {
510      int64_t Off = SO.SPOffset - ValOffset;
511      OS << ", at location [SP";
512      if (Off > 0)
513        OS << "+" << Off;
514      else if (Off < 0)
515        OS << Off;
516      OS << "]";
517    }
518    OS << "\n";
519  }
520}
521
522void MachineFrameInfo::dump(const MachineFunction &MF) const {
523  print(MF, dbgs());
524}
525
526//===----------------------------------------------------------------------===//
527//  MachineJumpTableInfo implementation
528//===----------------------------------------------------------------------===//
529
530/// getEntrySize - Return the size of each entry in the jump table.
531unsigned MachineJumpTableInfo::getEntrySize(const TargetData &TD) const {
532  // The size of a jump table entry is 4 bytes unless the entry is just the
533  // address of a block, in which case it is the pointer size.
534  switch (getEntryKind()) {
535  case MachineJumpTableInfo::EK_BlockAddress:
536    return TD.getPointerSize();
537  case MachineJumpTableInfo::EK_GPRel32BlockAddress:
538  case MachineJumpTableInfo::EK_LabelDifference32:
539  case MachineJumpTableInfo::EK_Custom32:
540    return 4;
541  case MachineJumpTableInfo::EK_Inline:
542    return 0;
543  }
544  assert(0 && "Unknown jump table encoding!");
545  return ~0;
546}
547
548/// getEntryAlignment - Return the alignment of each entry in the jump table.
549unsigned MachineJumpTableInfo::getEntryAlignment(const TargetData &TD) const {
550  // The alignment of a jump table entry is the alignment of int32 unless the
551  // entry is just the address of a block, in which case it is the pointer
552  // alignment.
553  switch (getEntryKind()) {
554  case MachineJumpTableInfo::EK_BlockAddress:
555    return TD.getPointerABIAlignment();
556  case MachineJumpTableInfo::EK_GPRel32BlockAddress:
557  case MachineJumpTableInfo::EK_LabelDifference32:
558  case MachineJumpTableInfo::EK_Custom32:
559    return TD.getABIIntegerTypeAlignment(32);
560  case MachineJumpTableInfo::EK_Inline:
561    return 1;
562  }
563  assert(0 && "Unknown jump table encoding!");
564  return ~0;
565}
566
567/// createJumpTableIndex - Create a new jump table entry in the jump table info.
568///
569unsigned MachineJumpTableInfo::createJumpTableIndex(
570                               const std::vector<MachineBasicBlock*> &DestBBs) {
571  assert(!DestBBs.empty() && "Cannot create an empty jump table!");
572  JumpTables.push_back(MachineJumpTableEntry(DestBBs));
573  return JumpTables.size()-1;
574}
575
576/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update
577/// the jump tables to branch to New instead.
578bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
579                                                  MachineBasicBlock *New) {
580  assert(Old != New && "Not making a change?");
581  bool MadeChange = false;
582  for (size_t i = 0, e = JumpTables.size(); i != e; ++i)
583    ReplaceMBBInJumpTable(i, Old, New);
584  return MadeChange;
585}
586
587/// ReplaceMBBInJumpTable - If Old is a target of the jump tables, update
588/// the jump table to branch to New instead.
589bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
590                                                 MachineBasicBlock *Old,
591                                                 MachineBasicBlock *New) {
592  assert(Old != New && "Not making a change?");
593  bool MadeChange = false;
594  MachineJumpTableEntry &JTE = JumpTables[Idx];
595  for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j)
596    if (JTE.MBBs[j] == Old) {
597      JTE.MBBs[j] = New;
598      MadeChange = true;
599    }
600  return MadeChange;
601}
602
603void MachineJumpTableInfo::print(raw_ostream &OS) const {
604  if (JumpTables.empty()) return;
605
606  OS << "Jump Tables:\n";
607
608  for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
609    OS << "  jt#" << i << ": ";
610    for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j)
611      OS << " BB#" << JumpTables[i].MBBs[j]->getNumber();
612  }
613
614  OS << '\n';
615}
616
617void MachineJumpTableInfo::dump() const { print(dbgs()); }
618
619
620//===----------------------------------------------------------------------===//
621//  MachineConstantPool implementation
622//===----------------------------------------------------------------------===//
623
624const Type *MachineConstantPoolEntry::getType() const {
625  if (isMachineConstantPoolEntry())
626    return Val.MachineCPVal->getType();
627  return Val.ConstVal->getType();
628}
629
630
631unsigned MachineConstantPoolEntry::getRelocationInfo() const {
632  if (isMachineConstantPoolEntry())
633    return Val.MachineCPVal->getRelocationInfo();
634  return Val.ConstVal->getRelocationInfo();
635}
636
637MachineConstantPool::~MachineConstantPool() {
638  for (unsigned i = 0, e = Constants.size(); i != e; ++i)
639    if (Constants[i].isMachineConstantPoolEntry())
640      delete Constants[i].Val.MachineCPVal;
641}
642
643/// CanShareConstantPoolEntry - Test whether the given two constants
644/// can be allocated the same constant pool entry.
645static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
646                                      const TargetData *TD) {
647  // Handle the trivial case quickly.
648  if (A == B) return true;
649
650  // If they have the same type but weren't the same constant, quickly
651  // reject them.
652  if (A->getType() == B->getType()) return false;
653
654  // For now, only support constants with the same size.
655  if (TD->getTypeStoreSize(A->getType()) != TD->getTypeStoreSize(B->getType()))
656    return false;
657
658  // If a floating-point value and an integer value have the same encoding,
659  // they can share a constant-pool entry.
660  if (const ConstantFP *AFP = dyn_cast<ConstantFP>(A))
661    if (const ConstantInt *BI = dyn_cast<ConstantInt>(B))
662      return AFP->getValueAPF().bitcastToAPInt() == BI->getValue();
663  if (const ConstantFP *BFP = dyn_cast<ConstantFP>(B))
664    if (const ConstantInt *AI = dyn_cast<ConstantInt>(A))
665      return BFP->getValueAPF().bitcastToAPInt() == AI->getValue();
666
667  // Two vectors can share an entry if each pair of corresponding
668  // elements could.
669  if (const ConstantVector *AV = dyn_cast<ConstantVector>(A))
670    if (const ConstantVector *BV = dyn_cast<ConstantVector>(B)) {
671      if (AV->getType()->getNumElements() != BV->getType()->getNumElements())
672        return false;
673      for (unsigned i = 0, e = AV->getType()->getNumElements(); i != e; ++i)
674        if (!CanShareConstantPoolEntry(AV->getOperand(i),
675                                       BV->getOperand(i), TD))
676          return false;
677      return true;
678    }
679
680  // TODO: Handle other cases.
681
682  return false;
683}
684
685/// getConstantPoolIndex - Create a new entry in the constant pool or return
686/// an existing one.  User must specify the log2 of the minimum required
687/// alignment for the object.
688///
689unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
690                                                   unsigned Alignment) {
691  assert(Alignment && "Alignment must be specified!");
692  if (Alignment > PoolAlignment) PoolAlignment = Alignment;
693
694  // Check to see if we already have this constant.
695  //
696  // FIXME, this could be made much more efficient for large constant pools.
697  for (unsigned i = 0, e = Constants.size(); i != e; ++i)
698    if (!Constants[i].isMachineConstantPoolEntry() &&
699        CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, TD)) {
700      if ((unsigned)Constants[i].getAlignment() < Alignment)
701        Constants[i].Alignment = Alignment;
702      return i;
703    }
704
705  Constants.push_back(MachineConstantPoolEntry(C, Alignment));
706  return Constants.size()-1;
707}
708
709unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
710                                                   unsigned Alignment) {
711  assert(Alignment && "Alignment must be specified!");
712  if (Alignment > PoolAlignment) PoolAlignment = Alignment;
713
714  // Check to see if we already have this constant.
715  //
716  // FIXME, this could be made much more efficient for large constant pools.
717  int Idx = V->getExistingMachineCPValue(this, Alignment);
718  if (Idx != -1)
719    return (unsigned)Idx;
720
721  Constants.push_back(MachineConstantPoolEntry(V, Alignment));
722  return Constants.size()-1;
723}
724
725void MachineConstantPool::print(raw_ostream &OS) const {
726  if (Constants.empty()) return;
727
728  OS << "Constant Pool:\n";
729  for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
730    OS << "  cp#" << i << ": ";
731    if (Constants[i].isMachineConstantPoolEntry())
732      Constants[i].Val.MachineCPVal->print(OS);
733    else
734      OS << *(Value*)Constants[i].Val.ConstVal;
735    OS << ", align=" << Constants[i].getAlignment();
736    OS << "\n";
737  }
738}
739
740void MachineConstantPool::dump() const { print(dbgs()); }
741