MachineFunction.cpp revision 86441169da23959c81d8648c3dfdc7a0bb8d2225 
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  // Don't call destructors on MachineInstr and MachineOperand. All of their
80  // memory comes from the BumpPtrAllocator which is about to be purged.
81  //
82  // Do call MachineBasicBlock destructors, it contains std::vectors.
83  for (iterator I = begin(), E = end(); I != E; I = BasicBlocks.erase(I))
84    I->Insts.clearAndLeakNodesUnsafely();
85
86  InstructionRecycler.clear(Allocator);
87  OperandRecycler.clear(Allocator);
88  BasicBlockRecycler.clear(Allocator);
89  if (RegInfo) {
90    RegInfo->~MachineRegisterInfo();
91    Allocator.Deallocate(RegInfo);
92  }
93  if (MFInfo) {
94    MFInfo->~MachineFunctionInfo();
95    Allocator.Deallocate(MFInfo);
96  }
97
98  FrameInfo->~MachineFrameInfo();
99  Allocator.Deallocate(FrameInfo);
100
101  ConstantPool->~MachineConstantPool();
102  Allocator.Deallocate(ConstantPool);
103
104  if (JumpTableInfo) {
105    JumpTableInfo->~MachineJumpTableInfo();
106    Allocator.Deallocate(JumpTableInfo);
107  }
108}
109
110/// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it
111/// does already exist, allocate one.
112MachineJumpTableInfo *MachineFunction::
113getOrCreateJumpTableInfo(unsigned EntryKind) {
114  if (JumpTableInfo) return JumpTableInfo;
115
116  JumpTableInfo = new (Allocator)
117    MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind);
118  return JumpTableInfo;
119}
120
121/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and
122/// recomputes them.  This guarantees that the MBB numbers are sequential,
123/// dense, and match the ordering of the blocks within the function.  If a
124/// specific MachineBasicBlock is specified, only that block and those after
125/// it are renumbered.
126void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
127  if (empty()) { MBBNumbering.clear(); return; }
128  MachineFunction::iterator MBBI, E = end();
129  if (MBB == 0)
130    MBBI = begin();
131  else
132    MBBI = MBB;
133
134  // Figure out the block number this should have.
135  unsigned BlockNo = 0;
136  if (MBBI != begin())
137    BlockNo = prior(MBBI)->getNumber()+1;
138
139  for (; MBBI != E; ++MBBI, ++BlockNo) {
140    if (MBBI->getNumber() != (int)BlockNo) {
141      // Remove use of the old number.
142      if (MBBI->getNumber() != -1) {
143        assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
144               "MBB number mismatch!");
145        MBBNumbering[MBBI->getNumber()] = 0;
146      }
147
148      // If BlockNo is already taken, set that block's number to -1.
149      if (MBBNumbering[BlockNo])
150        MBBNumbering[BlockNo]->setNumber(-1);
151
152      MBBNumbering[BlockNo] = MBBI;
153      MBBI->setNumber(BlockNo);
154    }
155  }
156
157  // Okay, all the blocks are renumbered.  If we have compactified the block
158  // numbering, shrink MBBNumbering now.
159  assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
160  MBBNumbering.resize(BlockNo);
161}
162
163/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead
164/// of `new MachineInstr'.
165///
166MachineInstr *
167MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
168                                    DebugLoc DL, bool NoImp) {
169  return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
170    MachineInstr(*this, MCID, DL, NoImp);
171}
172
173/// CloneMachineInstr - Create a new MachineInstr which is a copy of the
174/// 'Orig' instruction, identical in all ways except the instruction
175/// has no parent, prev, or next.
176///
177MachineInstr *
178MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
179  return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
180             MachineInstr(*this, *Orig);
181}
182
183/// DeleteMachineInstr - Delete the given MachineInstr.
184///
185/// This function also serves as the MachineInstr destructor - the real
186/// ~MachineInstr() destructor must be empty.
187void
188MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
189  // Strip it for parts. The operand array and the MI object itself are
190  // independently recyclable.
191  if (MI->Operands)
192    deallocateOperandArray(MI->CapOperands, MI->Operands);
193  // Don't call ~MachineInstr() which must be trivial anyway because
194  // ~MachineFunction drops whole lists of MachineInstrs wihout calling their
195  // destructors.
196  InstructionRecycler.Deallocate(Allocator, MI);
197}
198
199/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this
200/// instead of `new MachineBasicBlock'.
201///
202MachineBasicBlock *
203MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) {
204  return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
205             MachineBasicBlock(*this, bb);
206}
207
208/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock.
209///
210void
211MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
212  assert(MBB->getParent() == this && "MBB parent mismatch!");
213  MBB->~MachineBasicBlock();
214  BasicBlockRecycler.Deallocate(Allocator, MBB);
215}
216
217MachineMemOperand *
218MachineFunction::getMachineMemOperand(MachinePointerInfo PtrInfo, unsigned f,
219                                      uint64_t s, unsigned base_alignment,
220                                      const MDNode *TBAAInfo,
221                                      const MDNode *Ranges) {
222  return new (Allocator) MachineMemOperand(PtrInfo, f, s, base_alignment,
223                                           TBAAInfo, Ranges);
224}
225
226MachineMemOperand *
227MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
228                                      int64_t Offset, uint64_t Size) {
229  return new (Allocator)
230             MachineMemOperand(MachinePointerInfo(MMO->getValue(),
231                                                  MMO->getOffset()+Offset),
232                               MMO->getFlags(), Size,
233                               MMO->getBaseAlignment(), 0);
234}
235
236MachineInstr::mmo_iterator
237MachineFunction::allocateMemRefsArray(unsigned long Num) {
238  return Allocator.Allocate<MachineMemOperand *>(Num);
239}
240
241std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
242MachineFunction::extractLoadMemRefs(MachineInstr::mmo_iterator Begin,
243                                    MachineInstr::mmo_iterator End) {
244  // Count the number of load mem refs.
245  unsigned Num = 0;
246  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
247    if ((*I)->isLoad())
248      ++Num;
249
250  // Allocate a new array and populate it with the load information.
251  MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
252  unsigned Index = 0;
253  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
254    if ((*I)->isLoad()) {
255      if (!(*I)->isStore())
256        // Reuse the MMO.
257        Result[Index] = *I;
258      else {
259        // Clone the MMO and unset the store flag.
260        MachineMemOperand *JustLoad =
261          getMachineMemOperand((*I)->getPointerInfo(),
262                               (*I)->getFlags() & ~MachineMemOperand::MOStore,
263                               (*I)->getSize(), (*I)->getBaseAlignment(),
264                               (*I)->getTBAAInfo());
265        Result[Index] = JustLoad;
266      }
267      ++Index;
268    }
269  }
270  return std::make_pair(Result, Result + Num);
271}
272
273std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
274MachineFunction::extractStoreMemRefs(MachineInstr::mmo_iterator Begin,
275                                     MachineInstr::mmo_iterator End) {
276  // Count the number of load mem refs.
277  unsigned Num = 0;
278  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
279    if ((*I)->isStore())
280      ++Num;
281
282  // Allocate a new array and populate it with the store information.
283  MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
284  unsigned Index = 0;
285  for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
286    if ((*I)->isStore()) {
287      if (!(*I)->isLoad())
288        // Reuse the MMO.
289        Result[Index] = *I;
290      else {
291        // Clone the MMO and unset the load flag.
292        MachineMemOperand *JustStore =
293          getMachineMemOperand((*I)->getPointerInfo(),
294                               (*I)->getFlags() & ~MachineMemOperand::MOLoad,
295                               (*I)->getSize(), (*I)->getBaseAlignment(),
296                               (*I)->getTBAAInfo());
297        Result[Index] = JustStore;
298      }
299      ++Index;
300    }
301  }
302  return std::make_pair(Result, Result + Num);
303}
304
305#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
306void MachineFunction::dump() const {
307  print(dbgs());
308}
309#endif
310
311StringRef MachineFunction::getName() const {
312  assert(getFunction() && "No function!");
313  return getFunction()->getName();
314}
315
316void MachineFunction::print(raw_ostream &OS, SlotIndexes *Indexes) const {
317  OS << "# Machine code for function " << getName() << ": ";
318  if (RegInfo) {
319    OS << (RegInfo->isSSA() ? "SSA" : "Post SSA");
320    if (!RegInfo->tracksLiveness())
321      OS << ", not tracking liveness";
322  }
323  OS << '\n';
324
325  // Print Frame Information
326  FrameInfo->print(*this, OS);
327
328  // Print JumpTable Information
329  if (JumpTableInfo)
330    JumpTableInfo->print(OS);
331
332  // Print Constant Pool
333  ConstantPool->print(OS);
334
335  const TargetRegisterInfo *TRI = getTarget().getRegisterInfo();
336
337  if (RegInfo && !RegInfo->livein_empty()) {
338    OS << "Function Live Ins: ";
339    for (MachineRegisterInfo::livein_iterator
340         I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
341      OS << PrintReg(I->first, TRI);
342      if (I->second)
343        OS << " in " << PrintReg(I->second, TRI);
344      if (llvm::next(I) != E)
345        OS << ", ";
346    }
347    OS << '\n';
348  }
349  if (RegInfo && !RegInfo->liveout_empty()) {
350    OS << "Function Live Outs:";
351    for (MachineRegisterInfo::liveout_iterator
352         I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I)
353      OS << ' ' << PrintReg(*I, TRI);
354    OS << '\n';
355  }
356
357  for (const_iterator BB = begin(), E = end(); BB != E; ++BB) {
358    OS << '\n';
359    BB->print(OS, Indexes);
360  }
361
362  OS << "\n# End machine code for function " << getName() << ".\n\n";
363}
364
365namespace llvm {
366  template<>
367  struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
368
369  DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
370
371    static std::string getGraphName(const MachineFunction *F) {
372      return "CFG for '" + F->getName().str() + "' function";
373    }
374
375    std::string getNodeLabel(const MachineBasicBlock *Node,
376                             const MachineFunction *Graph) {
377      std::string OutStr;
378      {
379        raw_string_ostream OSS(OutStr);
380
381        if (isSimple()) {
382          OSS << "BB#" << Node->getNumber();
383          if (const BasicBlock *BB = Node->getBasicBlock())
384            OSS << ": " << BB->getName();
385        } else
386          Node->print(OSS);
387      }
388
389      if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
390
391      // Process string output to make it nicer...
392      for (unsigned i = 0; i != OutStr.length(); ++i)
393        if (OutStr[i] == '\n') {                            // Left justify
394          OutStr[i] = '\\';
395          OutStr.insert(OutStr.begin()+i+1, 'l');
396        }
397      return OutStr;
398    }
399  };
400}
401
402void MachineFunction::viewCFG() const
403{
404#ifndef NDEBUG
405  ViewGraph(this, "mf" + getName());
406#else
407  errs() << "MachineFunction::viewCFG is only available in debug builds on "
408         << "systems with Graphviz or gv!\n";
409#endif // NDEBUG
410}
411
412void MachineFunction::viewCFGOnly() const
413{
414#ifndef NDEBUG
415  ViewGraph(this, "mf" + getName(), true);
416#else
417  errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
418         << "systems with Graphviz or gv!\n";
419#endif // NDEBUG
420}
421
422/// addLiveIn - Add the specified physical register as a live-in value and
423/// create a corresponding virtual register for it.
424unsigned MachineFunction::addLiveIn(unsigned PReg,
425                                    const TargetRegisterClass *RC) {
426  MachineRegisterInfo &MRI = getRegInfo();
427  unsigned VReg = MRI.getLiveInVirtReg(PReg);
428  if (VReg) {
429    assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!");
430    return VReg;
431  }
432  VReg = MRI.createVirtualRegister(RC);
433  MRI.addLiveIn(PReg, VReg);
434  return VReg;
435}
436
437/// getJTISymbol - Return the MCSymbol for the specified non-empty jump table.
438/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
439/// normal 'L' label is returned.
440MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
441                                        bool isLinkerPrivate) const {
442  assert(JumpTableInfo && "No jump tables");
443  assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
444  const MCAsmInfo &MAI = *getTarget().getMCAsmInfo();
445
446  const char *Prefix = isLinkerPrivate ? MAI.getLinkerPrivateGlobalPrefix() :
447                                         MAI.getPrivateGlobalPrefix();
448  SmallString<60> Name;
449  raw_svector_ostream(Name)
450    << Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
451  return Ctx.GetOrCreateSymbol(Name.str());
452}
453
454/// getPICBaseSymbol - Return a function-local symbol to represent the PIC
455/// base.
456MCSymbol *MachineFunction::getPICBaseSymbol() const {
457  const MCAsmInfo &MAI = *Target.getMCAsmInfo();
458  return Ctx.GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix())+
459                               Twine(getFunctionNumber())+"$pb");
460}
461
462//===----------------------------------------------------------------------===//
463//  MachineFrameInfo implementation
464//===----------------------------------------------------------------------===//
465
466/// ensureMaxAlignment - Make sure the function is at least Align bytes
467/// aligned.
468void MachineFrameInfo::ensureMaxAlignment(unsigned Align) {
469  if (!TFI.isStackRealignable() || !RealignOption)
470    assert(Align <= TFI.getStackAlignment() &&
471           "For targets without stack realignment, Align is out of limit!");
472  if (MaxAlignment < Align) MaxAlignment = Align;
473}
474
475/// clampStackAlignment - Clamp the alignment if requested and emit a warning.
476static inline unsigned clampStackAlignment(bool ShouldClamp, unsigned PrefAlign,
477                         unsigned MinAlign, unsigned StackAlign,
478                         const AllocaInst *Alloca = 0) {
479  if (!ShouldClamp || PrefAlign <= StackAlign)
480    return PrefAlign;
481  if (Alloca && MinAlign > StackAlign)
482    Alloca->getParent()->getContext().emitError(Alloca,
483        "Requested Minimal Alignment exceeds the Stack Alignment!");
484  else
485    assert(MinAlign <= StackAlign &&
486           "Requested Minimal Alignment exceeds the Stack Alignment!");
487  return StackAlign;
488}
489
490/// CreateStackObjectWithMinAlign - Create a new statically sized stack
491/// object, returning a nonnegative identifier to represent it. This function
492/// takes a preferred alignment and a minimal alignment.
493///
494int MachineFrameInfo::CreateStackObjectWithMinAlign(uint64_t Size,
495                          unsigned PrefAlignment, unsigned MinAlignment,
496                          bool isSS, bool MayNeedSP, const AllocaInst *Alloca) {
497  assert(Size != 0 && "Cannot allocate zero size stack objects!");
498  unsigned Alignment = clampStackAlignment(
499                           !TFI.isStackRealignable() || !RealignOption,
500                           PrefAlignment, MinAlignment,
501                           TFI.getStackAlignment(), Alloca);
502  Objects.push_back(StackObject(Size, Alignment, 0, false, isSS, MayNeedSP,
503                                Alloca));
504  int Index = (int)Objects.size() - NumFixedObjects - 1;
505  assert(Index >= 0 && "Bad frame index!");
506  ensureMaxAlignment(Alignment);
507  return Index;
508}
509
510/// CreateSpillStackObject - Create a new statically sized stack object that
511/// represents a spill slot, returning a nonnegative identifier to represent
512/// it.
513///
514int MachineFrameInfo::CreateSpillStackObject(uint64_t Size,
515                                             unsigned Alignment) {
516  Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
517                                  Alignment, 0,
518                                  TFI.getStackAlignment());
519  CreateStackObject(Size, Alignment, true, false);
520  int Index = (int)Objects.size() - NumFixedObjects - 1;
521  ensureMaxAlignment(Alignment);
522  return Index;
523}
524
525/// CreateVariableSizedObject - Notify the MachineFrameInfo object that a
526/// variable sized object has been created.  This must be created whenever a
527/// variable sized object is created, whether or not the index returned is
528/// actually used.
529///
530int MachineFrameInfo::CreateVariableSizedObject(unsigned PrefAlignment,
531                        unsigned MinAlignment, const AllocaInst *Alloca) {
532  HasVarSizedObjects = true;
533  unsigned Alignment = clampStackAlignment(
534                           !TFI.isStackRealignable() || !RealignOption,
535                           PrefAlignment, MinAlignment,
536                           TFI.getStackAlignment(), Alloca);
537  Objects.push_back(StackObject(0, Alignment, 0, false, false, true, 0));
538  ensureMaxAlignment(Alignment);
539  return (int)Objects.size()-NumFixedObjects-1;
540}
541
542/// CreateFixedObject - Create a new object at a fixed location on the stack.
543/// All fixed objects should be created before other objects are created for
544/// efficiency. By default, fixed objects are immutable. This returns an
545/// index with a negative value.
546///
547int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset,
548                                        bool Immutable) {
549  assert(Size != 0 && "Cannot allocate zero size fixed stack objects!");
550  // The alignment of the frame index can be determined from its offset from
551  // the incoming frame position.  If the frame object is at offset 32 and
552  // the stack is guaranteed to be 16-byte aligned, then we know that the
553  // object is 16-byte aligned.
554  unsigned StackAlign = TFI.getStackAlignment();
555  unsigned Align = MinAlign(SPOffset, StackAlign);
556  Align = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
557                              Align, 0, TFI.getStackAlignment());
558  Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable,
559                                              /*isSS*/   false,
560                                              /*NeedSP*/ false,
561                                              /*Alloca*/ 0));
562  return -++NumFixedObjects;
563}
564
565
566BitVector
567MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const {
568  assert(MBB && "MBB must be valid");
569  const MachineFunction *MF = MBB->getParent();
570  assert(MF && "MBB must be part of a MachineFunction");
571  const TargetMachine &TM = MF->getTarget();
572  const TargetRegisterInfo *TRI = TM.getRegisterInfo();
573  BitVector BV(TRI->getNumRegs());
574
575  // Before CSI is calculated, no registers are considered pristine. They can be
576  // freely used and PEI will make sure they are saved.
577  if (!isCalleeSavedInfoValid())
578    return BV;
579
580  for (const uint16_t *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR)
581    BV.set(*CSR);
582
583  // The entry MBB always has all CSRs pristine.
584  if (MBB == &MF->front())
585    return BV;
586
587  // On other MBBs the saved CSRs are not pristine.
588  const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo();
589  for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
590         E = CSI.end(); I != E; ++I)
591    BV.reset(I->getReg());
592
593  return BV;
594}
595
596
597void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{
598  if (Objects.empty()) return;
599
600  const TargetFrameLowering *FI = MF.getTarget().getFrameLowering();
601  int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
602
603  OS << "Frame Objects:\n";
604
605  for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
606    const StackObject &SO = Objects[i];
607    OS << "  fi#" << (int)(i-NumFixedObjects) << ": ";
608    if (SO.Size == ~0ULL) {
609      OS << "dead\n";
610      continue;
611    }
612    if (SO.Size == 0)
613      OS << "variable sized";
614    else
615      OS << "size=" << SO.Size;
616    OS << ", align=" << SO.Alignment;
617
618    if (i < NumFixedObjects)
619      OS << ", fixed";
620    if (i < NumFixedObjects || SO.SPOffset != -1) {
621      int64_t Off = SO.SPOffset - ValOffset;
622      OS << ", at location [SP";
623      if (Off > 0)
624        OS << "+" << Off;
625      else if (Off < 0)
626        OS << Off;
627      OS << "]";
628    }
629    OS << "\n";
630  }
631}
632
633#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
634void MachineFrameInfo::dump(const MachineFunction &MF) const {
635  print(MF, dbgs());
636}
637#endif
638
639//===----------------------------------------------------------------------===//
640//  MachineJumpTableInfo implementation
641//===----------------------------------------------------------------------===//
642
643/// getEntrySize - Return the size of each entry in the jump table.
644unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
645  // The size of a jump table entry is 4 bytes unless the entry is just the
646  // address of a block, in which case it is the pointer size.
647  switch (getEntryKind()) {
648  case MachineJumpTableInfo::EK_BlockAddress:
649    return TD.getPointerSize();
650  case MachineJumpTableInfo::EK_GPRel64BlockAddress:
651    return 8;
652  case MachineJumpTableInfo::EK_GPRel32BlockAddress:
653  case MachineJumpTableInfo::EK_LabelDifference32:
654  case MachineJumpTableInfo::EK_Custom32:
655    return 4;
656  case MachineJumpTableInfo::EK_Inline:
657    return 0;
658  }
659  llvm_unreachable("Unknown jump table encoding!");
660}
661
662/// getEntryAlignment - Return the alignment of each entry in the jump table.
663unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
664  // The alignment of a jump table entry is the alignment of int32 unless the
665  // entry is just the address of a block, in which case it is the pointer
666  // alignment.
667  switch (getEntryKind()) {
668  case MachineJumpTableInfo::EK_BlockAddress:
669    return TD.getPointerABIAlignment();
670  case MachineJumpTableInfo::EK_GPRel64BlockAddress:
671    return TD.getABIIntegerTypeAlignment(64);
672  case MachineJumpTableInfo::EK_GPRel32BlockAddress:
673  case MachineJumpTableInfo::EK_LabelDifference32:
674  case MachineJumpTableInfo::EK_Custom32:
675    return TD.getABIIntegerTypeAlignment(32);
676  case MachineJumpTableInfo::EK_Inline:
677    return 1;
678  }
679  llvm_unreachable("Unknown jump table encoding!");
680}
681
682/// createJumpTableIndex - Create a new jump table entry in the jump table info.
683///
684unsigned MachineJumpTableInfo::createJumpTableIndex(
685                               const std::vector<MachineBasicBlock*> &DestBBs) {
686  assert(!DestBBs.empty() && "Cannot create an empty jump table!");
687  JumpTables.push_back(MachineJumpTableEntry(DestBBs));
688  return JumpTables.size()-1;
689}
690
691/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update
692/// the jump tables to branch to New instead.
693bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
694                                                  MachineBasicBlock *New) {
695  assert(Old != New && "Not making a change?");
696  bool MadeChange = false;
697  for (size_t i = 0, e = JumpTables.size(); i != e; ++i)
698    ReplaceMBBInJumpTable(i, Old, New);
699  return MadeChange;
700}
701
702/// ReplaceMBBInJumpTable - If Old is a target of the jump tables, update
703/// the jump table to branch to New instead.
704bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
705                                                 MachineBasicBlock *Old,
706                                                 MachineBasicBlock *New) {
707  assert(Old != New && "Not making a change?");
708  bool MadeChange = false;
709  MachineJumpTableEntry &JTE = JumpTables[Idx];
710  for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j)
711    if (JTE.MBBs[j] == Old) {
712      JTE.MBBs[j] = New;
713      MadeChange = true;
714    }
715  return MadeChange;
716}
717
718void MachineJumpTableInfo::print(raw_ostream &OS) const {
719  if (JumpTables.empty()) return;
720
721  OS << "Jump Tables:\n";
722
723  for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
724    OS << "  jt#" << i << ": ";
725    for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j)
726      OS << " BB#" << JumpTables[i].MBBs[j]->getNumber();
727  }
728
729  OS << '\n';
730}
731
732#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
733void MachineJumpTableInfo::dump() const { print(dbgs()); }
734#endif
735
736
737//===----------------------------------------------------------------------===//
738//  MachineConstantPool implementation
739//===----------------------------------------------------------------------===//
740
741void MachineConstantPoolValue::anchor() { }
742
743Type *MachineConstantPoolEntry::getType() const {
744  if (isMachineConstantPoolEntry())
745    return Val.MachineCPVal->getType();
746  return Val.ConstVal->getType();
747}
748
749
750unsigned MachineConstantPoolEntry::getRelocationInfo() const {
751  if (isMachineConstantPoolEntry())
752    return Val.MachineCPVal->getRelocationInfo();
753  return Val.ConstVal->getRelocationInfo();
754}
755
756MachineConstantPool::~MachineConstantPool() {
757  for (unsigned i = 0, e = Constants.size(); i != e; ++i)
758    if (Constants[i].isMachineConstantPoolEntry())
759      delete Constants[i].Val.MachineCPVal;
760  for (DenseSet<MachineConstantPoolValue*>::iterator I =
761       MachineCPVsSharingEntries.begin(), E = MachineCPVsSharingEntries.end();
762       I != E; ++I)
763    delete *I;
764}
765
766/// CanShareConstantPoolEntry - Test whether the given two constants
767/// can be allocated the same constant pool entry.
768static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
769                                      const DataLayout *TD) {
770  // Handle the trivial case quickly.
771  if (A == B) return true;
772
773  // If they have the same type but weren't the same constant, quickly
774  // reject them.
775  if (A->getType() == B->getType()) return false;
776
777  // We can't handle structs or arrays.
778  if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) ||
779      isa<StructType>(B->getType()) || isa<ArrayType>(B->getType()))
780    return false;
781
782  // For now, only support constants with the same size.
783  uint64_t StoreSize = TD->getTypeStoreSize(A->getType());
784  if (StoreSize != TD->getTypeStoreSize(B->getType()) ||
785      StoreSize > 128)
786    return false;
787
788  Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8);
789
790  // Try constant folding a bitcast of both instructions to an integer.  If we
791  // get two identical ConstantInt's, then we are good to share them.  We use
792  // the constant folding APIs to do this so that we get the benefit of
793  // DataLayout.
794  if (isa<PointerType>(A->getType()))
795    A = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy,
796                                 const_cast<Constant*>(A), TD);
797  else if (A->getType() != IntTy)
798    A = ConstantFoldInstOperands(Instruction::BitCast, IntTy,
799                                 const_cast<Constant*>(A), TD);
800  if (isa<PointerType>(B->getType()))
801    B = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy,
802                                 const_cast<Constant*>(B), TD);
803  else if (B->getType() != IntTy)
804    B = ConstantFoldInstOperands(Instruction::BitCast, IntTy,
805                                 const_cast<Constant*>(B), TD);
806
807  return A == B;
808}
809
810/// getConstantPoolIndex - Create a new entry in the constant pool or return
811/// an existing one.  User must specify the log2 of the minimum required
812/// alignment for the object.
813///
814unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
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  for (unsigned i = 0, e = Constants.size(); i != e; ++i)
823    if (!Constants[i].isMachineConstantPoolEntry() &&
824        CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, TD)) {
825      if ((unsigned)Constants[i].getAlignment() < Alignment)
826        Constants[i].Alignment = Alignment;
827      return i;
828    }
829
830  Constants.push_back(MachineConstantPoolEntry(C, Alignment));
831  return Constants.size()-1;
832}
833
834unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
835                                                   unsigned Alignment) {
836  assert(Alignment && "Alignment must be specified!");
837  if (Alignment > PoolAlignment) PoolAlignment = Alignment;
838
839  // Check to see if we already have this constant.
840  //
841  // FIXME, this could be made much more efficient for large constant pools.
842  int Idx = V->getExistingMachineCPValue(this, Alignment);
843  if (Idx != -1) {
844    MachineCPVsSharingEntries.insert(V);
845    return (unsigned)Idx;
846  }
847
848  Constants.push_back(MachineConstantPoolEntry(V, Alignment));
849  return Constants.size()-1;
850}
851
852void MachineConstantPool::print(raw_ostream &OS) const {
853  if (Constants.empty()) return;
854
855  OS << "Constant Pool:\n";
856  for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
857    OS << "  cp#" << i << ": ";
858    if (Constants[i].isMachineConstantPoolEntry())
859      Constants[i].Val.MachineCPVal->print(OS);
860    else
861      OS << *(const Value*)Constants[i].Val.ConstVal;
862    OS << ", align=" << Constants[i].getAlignment();
863    OS << "\n";
864  }
865}
866
867#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
868void MachineConstantPool::dump() const { print(dbgs()); }
869#endif
870