1 //===-- MachineFunction.cpp -----------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Collect native machine code information for a function. This allows
11 // target-specific information about the generated code to be stored with each
14 //===----------------------------------------------------------------------===//
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/Assembly/Writer.h"
21 #include "llvm/CodeGen/MachineConstantPool.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineFunctionPass.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/DebugInfo.h"
30 #include "llvm/IR/DataLayout.h"
31 #include "llvm/IR/Function.h"
32 #include "llvm/MC/MCAsmInfo.h"
33 #include "llvm/MC/MCContext.h"
34 #include "llvm/Support/Debug.h"
35 #include "llvm/Support/GraphWriter.h"
36 #include "llvm/Support/raw_ostream.h"
37 #include "llvm/Target/TargetFrameLowering.h"
38 #include "llvm/Target/TargetLowering.h"
39 #include "llvm/Target/TargetMachine.h"
42 //===----------------------------------------------------------------------===//
43 // MachineFunction implementation
44 //===----------------------------------------------------------------------===//
46 // Out of line virtual method.
47 MachineFunctionInfo::~MachineFunctionInfo() {}
49 void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) {
50 MBB->getParent()->DeleteMachineBasicBlock(MBB);
53 MachineFunction::MachineFunction(const Function *F, const TargetMachine &TM,
54 unsigned FunctionNum, MachineModuleInfo &mmi,
56 : Fn(F), Target(TM), Ctx(mmi.getContext()), MMI(mmi), GMI(gmi) {
57 if (TM.getRegisterInfo())
58 RegInfo = new (Allocator) MachineRegisterInfo(*TM.getRegisterInfo());
62 FrameInfo = new (Allocator) MachineFrameInfo(*TM.getFrameLowering(),
63 TM.Options.RealignStack);
64 if (Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
65 Attribute::StackAlignment))
66 FrameInfo->ensureMaxAlignment(Fn->getAttributes().
67 getStackAlignment(AttributeSet::FunctionIndex));
68 ConstantPool = new (Allocator) MachineConstantPool(TM.getDataLayout());
69 Alignment = TM.getTargetLowering()->getMinFunctionAlignment();
70 // FIXME: Shouldn't use pref alignment if explicit alignment is set on Fn.
71 if (!Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
72 Attribute::OptimizeForSize))
73 Alignment = std::max(Alignment,
74 TM.getTargetLowering()->getPrefFunctionAlignment());
75 FunctionNumber = FunctionNum;
79 MachineFunction::~MachineFunction() {
80 // Don't call destructors on MachineInstr and MachineOperand. All of their
81 // memory comes from the BumpPtrAllocator which is about to be purged.
83 // Do call MachineBasicBlock destructors, it contains std::vectors.
84 for (iterator I = begin(), E = end(); I != E; I = BasicBlocks.erase(I))
85 I->Insts.clearAndLeakNodesUnsafely();
87 InstructionRecycler.clear(Allocator);
88 OperandRecycler.clear(Allocator);
89 BasicBlockRecycler.clear(Allocator);
91 RegInfo->~MachineRegisterInfo();
92 Allocator.Deallocate(RegInfo);
95 MFInfo->~MachineFunctionInfo();
96 Allocator.Deallocate(MFInfo);
99 FrameInfo->~MachineFrameInfo();
100 Allocator.Deallocate(FrameInfo);
102 ConstantPool->~MachineConstantPool();
103 Allocator.Deallocate(ConstantPool);
106 JumpTableInfo->~MachineJumpTableInfo();
107 Allocator.Deallocate(JumpTableInfo);
111 /// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it
112 /// does already exist, allocate one.
113 MachineJumpTableInfo *MachineFunction::
114 getOrCreateJumpTableInfo(unsigned EntryKind) {
115 if (JumpTableInfo) return JumpTableInfo;
117 JumpTableInfo = new (Allocator)
118 MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind);
119 return JumpTableInfo;
122 /// RenumberBlocks - This discards all of the MachineBasicBlock numbers and
123 /// recomputes them. This guarantees that the MBB numbers are sequential,
124 /// dense, and match the ordering of the blocks within the function. If a
125 /// specific MachineBasicBlock is specified, only that block and those after
126 /// it are renumbered.
127 void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
128 if (empty()) { MBBNumbering.clear(); return; }
129 MachineFunction::iterator MBBI, E = end();
135 // Figure out the block number this should have.
136 unsigned BlockNo = 0;
138 BlockNo = prior(MBBI)->getNumber()+1;
140 for (; MBBI != E; ++MBBI, ++BlockNo) {
141 if (MBBI->getNumber() != (int)BlockNo) {
142 // Remove use of the old number.
143 if (MBBI->getNumber() != -1) {
144 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
145 "MBB number mismatch!");
146 MBBNumbering[MBBI->getNumber()] = 0;
149 // If BlockNo is already taken, set that block's number to -1.
150 if (MBBNumbering[BlockNo])
151 MBBNumbering[BlockNo]->setNumber(-1);
153 MBBNumbering[BlockNo] = MBBI;
154 MBBI->setNumber(BlockNo);
158 // Okay, all the blocks are renumbered. If we have compactified the block
159 // numbering, shrink MBBNumbering now.
160 assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
161 MBBNumbering.resize(BlockNo);
164 /// CreateMachineInstr - Allocate a new MachineInstr. Use this instead
165 /// of `new MachineInstr'.
168 MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
169 DebugLoc DL, bool NoImp) {
170 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
171 MachineInstr(*this, MCID, DL, NoImp);
174 /// CloneMachineInstr - Create a new MachineInstr which is a copy of the
175 /// 'Orig' instruction, identical in all ways except the instruction
176 /// has no parent, prev, or next.
179 MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
180 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
181 MachineInstr(*this, *Orig);
184 /// DeleteMachineInstr - Delete the given MachineInstr.
186 /// This function also serves as the MachineInstr destructor - the real
187 /// ~MachineInstr() destructor must be empty.
189 MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
190 // Strip it for parts. The operand array and the MI object itself are
191 // independently recyclable.
193 deallocateOperandArray(MI->CapOperands, MI->Operands);
194 // Don't call ~MachineInstr() which must be trivial anyway because
195 // ~MachineFunction drops whole lists of MachineInstrs wihout calling their
197 InstructionRecycler.Deallocate(Allocator, MI);
200 /// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this
201 /// instead of `new MachineBasicBlock'.
204 MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) {
205 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
206 MachineBasicBlock(*this, bb);
209 /// DeleteMachineBasicBlock - Delete the given MachineBasicBlock.
212 MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
213 assert(MBB->getParent() == this && "MBB parent mismatch!");
214 MBB->~MachineBasicBlock();
215 BasicBlockRecycler.Deallocate(Allocator, MBB);
219 MachineFunction::getMachineMemOperand(MachinePointerInfo PtrInfo, unsigned f,
220 uint64_t s, unsigned base_alignment,
221 const MDNode *TBAAInfo,
222 const MDNode *Ranges) {
223 return new (Allocator) MachineMemOperand(PtrInfo, f, s, base_alignment,
228 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
229 int64_t Offset, uint64_t Size) {
230 return new (Allocator)
231 MachineMemOperand(MachinePointerInfo(MMO->getValue(),
232 MMO->getOffset()+Offset),
233 MMO->getFlags(), Size,
234 MMO->getBaseAlignment(), 0);
237 MachineInstr::mmo_iterator
238 MachineFunction::allocateMemRefsArray(unsigned long Num) {
239 return Allocator.Allocate<MachineMemOperand *>(Num);
242 std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
243 MachineFunction::extractLoadMemRefs(MachineInstr::mmo_iterator Begin,
244 MachineInstr::mmo_iterator End) {
245 // Count the number of load mem refs.
247 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
251 // Allocate a new array and populate it with the load information.
252 MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
254 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
255 if ((*I)->isLoad()) {
256 if (!(*I)->isStore())
260 // Clone the MMO and unset the store flag.
261 MachineMemOperand *JustLoad =
262 getMachineMemOperand((*I)->getPointerInfo(),
263 (*I)->getFlags() & ~MachineMemOperand::MOStore,
264 (*I)->getSize(), (*I)->getBaseAlignment(),
265 (*I)->getTBAAInfo());
266 Result[Index] = JustLoad;
271 return std::make_pair(Result, Result + Num);
274 std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator>
275 MachineFunction::extractStoreMemRefs(MachineInstr::mmo_iterator Begin,
276 MachineInstr::mmo_iterator End) {
277 // Count the number of load mem refs.
279 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I)
283 // Allocate a new array and populate it with the store information.
284 MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num);
286 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) {
287 if ((*I)->isStore()) {
292 // Clone the MMO and unset the load flag.
293 MachineMemOperand *JustStore =
294 getMachineMemOperand((*I)->getPointerInfo(),
295 (*I)->getFlags() & ~MachineMemOperand::MOLoad,
296 (*I)->getSize(), (*I)->getBaseAlignment(),
297 (*I)->getTBAAInfo());
298 Result[Index] = JustStore;
303 return std::make_pair(Result, Result + Num);
306 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
307 void MachineFunction::dump() const {
312 StringRef MachineFunction::getName() const {
313 assert(getFunction() && "No function!");
314 return getFunction()->getName();
317 void MachineFunction::print(raw_ostream &OS, SlotIndexes *Indexes) const {
318 OS << "# Machine code for function " << getName() << ": ";
320 OS << (RegInfo->isSSA() ? "SSA" : "Post SSA");
321 if (!RegInfo->tracksLiveness())
322 OS << ", not tracking liveness";
326 // Print Frame Information
327 FrameInfo->print(*this, OS);
329 // Print JumpTable Information
331 JumpTableInfo->print(OS);
333 // Print Constant Pool
334 ConstantPool->print(OS);
336 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo();
338 if (RegInfo && !RegInfo->livein_empty()) {
339 OS << "Function Live Ins: ";
340 for (MachineRegisterInfo::livein_iterator
341 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
342 OS << PrintReg(I->first, TRI);
344 OS << " in " << PrintReg(I->second, TRI);
345 if (llvm::next(I) != E)
351 for (const_iterator BB = begin(), E = end(); BB != E; ++BB) {
353 BB->print(OS, Indexes);
356 OS << "\n# End machine code for function " << getName() << ".\n\n";
361 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
363 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
365 static std::string getGraphName(const MachineFunction *F) {
366 return "CFG for '" + F->getName().str() + "' function";
369 std::string getNodeLabel(const MachineBasicBlock *Node,
370 const MachineFunction *Graph) {
373 raw_string_ostream OSS(OutStr);
376 OSS << "BB#" << Node->getNumber();
377 if (const BasicBlock *BB = Node->getBasicBlock())
378 OSS << ": " << BB->getName();
383 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
385 // Process string output to make it nicer...
386 for (unsigned i = 0; i != OutStr.length(); ++i)
387 if (OutStr[i] == '\n') { // Left justify
389 OutStr.insert(OutStr.begin()+i+1, 'l');
396 void MachineFunction::viewCFG() const
399 ViewGraph(this, "mf" + getName());
401 errs() << "MachineFunction::viewCFG is only available in debug builds on "
402 << "systems with Graphviz or gv!\n";
406 void MachineFunction::viewCFGOnly() const
409 ViewGraph(this, "mf" + getName(), true);
411 errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
412 << "systems with Graphviz or gv!\n";
416 /// addLiveIn - Add the specified physical register as a live-in value and
417 /// create a corresponding virtual register for it.
418 unsigned MachineFunction::addLiveIn(unsigned PReg,
419 const TargetRegisterClass *RC) {
420 MachineRegisterInfo &MRI = getRegInfo();
421 unsigned VReg = MRI.getLiveInVirtReg(PReg);
423 assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!");
426 VReg = MRI.createVirtualRegister(RC);
427 MRI.addLiveIn(PReg, VReg);
431 /// getJTISymbol - Return the MCSymbol for the specified non-empty jump table.
432 /// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
433 /// normal 'L' label is returned.
434 MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
435 bool isLinkerPrivate) const {
436 assert(JumpTableInfo && "No jump tables");
437 assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
438 const MCAsmInfo &MAI = *getTarget().getMCAsmInfo();
440 const char *Prefix = isLinkerPrivate ? MAI.getLinkerPrivateGlobalPrefix() :
441 MAI.getPrivateGlobalPrefix();
442 SmallString<60> Name;
443 raw_svector_ostream(Name)
444 << Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
445 return Ctx.GetOrCreateSymbol(Name.str());
448 /// getPICBaseSymbol - Return a function-local symbol to represent the PIC
450 MCSymbol *MachineFunction::getPICBaseSymbol() const {
451 const MCAsmInfo &MAI = *Target.getMCAsmInfo();
452 return Ctx.GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix())+
453 Twine(getFunctionNumber())+"$pb");
456 //===----------------------------------------------------------------------===//
457 // MachineFrameInfo implementation
458 //===----------------------------------------------------------------------===//
460 /// ensureMaxAlignment - Make sure the function is at least Align bytes
462 void MachineFrameInfo::ensureMaxAlignment(unsigned Align) {
463 if (!TFI.isStackRealignable() || !RealignOption)
464 assert(Align <= TFI.getStackAlignment() &&
465 "For targets without stack realignment, Align is out of limit!");
466 if (MaxAlignment < Align) MaxAlignment = Align;
469 /// clampStackAlignment - Clamp the alignment if requested and emit a warning.
470 static inline unsigned clampStackAlignment(bool ShouldClamp, unsigned Align,
471 unsigned StackAlign) {
472 if (!ShouldClamp || Align <= StackAlign)
474 DEBUG(dbgs() << "Warning: requested alignment " << Align
475 << " exceeds the stack alignment " << StackAlign
476 << " when stack realignment is off" << '\n');
480 /// CreateStackObject - Create a new statically sized stack object, returning
481 /// a nonnegative identifier to represent it.
483 int MachineFrameInfo::CreateStackObject(uint64_t Size, unsigned Alignment,
484 bool isSS, bool MayNeedSP, const AllocaInst *Alloca) {
485 assert(Size != 0 && "Cannot allocate zero size stack objects!");
486 Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
487 Alignment, TFI.getStackAlignment());
488 Objects.push_back(StackObject(Size, Alignment, 0, false, isSS, MayNeedSP,
490 int Index = (int)Objects.size() - NumFixedObjects - 1;
491 assert(Index >= 0 && "Bad frame index!");
492 ensureMaxAlignment(Alignment);
496 /// CreateSpillStackObject - Create a new statically sized stack object that
497 /// represents a spill slot, returning a nonnegative identifier to represent
500 int MachineFrameInfo::CreateSpillStackObject(uint64_t Size,
501 unsigned Alignment) {
502 Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
503 Alignment, TFI.getStackAlignment());
504 CreateStackObject(Size, Alignment, true, false);
505 int Index = (int)Objects.size() - NumFixedObjects - 1;
506 ensureMaxAlignment(Alignment);
510 /// CreateVariableSizedObject - Notify the MachineFrameInfo object that a
511 /// variable sized object has been created. This must be created whenever a
512 /// variable sized object is created, whether or not the index returned is
515 int MachineFrameInfo::CreateVariableSizedObject(unsigned Alignment) {
516 HasVarSizedObjects = true;
517 Alignment = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
518 Alignment, TFI.getStackAlignment());
519 Objects.push_back(StackObject(0, Alignment, 0, false, false, true, 0));
520 ensureMaxAlignment(Alignment);
521 return (int)Objects.size()-NumFixedObjects-1;
524 /// CreateFixedObject - Create a new object at a fixed location on the stack.
525 /// All fixed objects should be created before other objects are created for
526 /// efficiency. By default, fixed objects are immutable. This returns an
527 /// index with a negative value.
529 int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset,
531 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!");
532 // The alignment of the frame index can be determined from its offset from
533 // the incoming frame position. If the frame object is at offset 32 and
534 // the stack is guaranteed to be 16-byte aligned, then we know that the
535 // object is 16-byte aligned.
536 unsigned StackAlign = TFI.getStackAlignment();
537 unsigned Align = MinAlign(SPOffset, StackAlign);
538 Align = clampStackAlignment(!TFI.isStackRealignable() || !RealignOption,
539 Align, TFI.getStackAlignment());
540 Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable,
544 return -++NumFixedObjects;
549 MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const {
550 assert(MBB && "MBB must be valid");
551 const MachineFunction *MF = MBB->getParent();
552 assert(MF && "MBB must be part of a MachineFunction");
553 const TargetMachine &TM = MF->getTarget();
554 const TargetRegisterInfo *TRI = TM.getRegisterInfo();
555 BitVector BV(TRI->getNumRegs());
557 // Before CSI is calculated, no registers are considered pristine. They can be
558 // freely used and PEI will make sure they are saved.
559 if (!isCalleeSavedInfoValid())
562 for (const uint16_t *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR)
565 // The entry MBB always has all CSRs pristine.
566 if (MBB == &MF->front())
569 // On other MBBs the saved CSRs are not pristine.
570 const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo();
571 for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
572 E = CSI.end(); I != E; ++I)
573 BV.reset(I->getReg());
578 unsigned MachineFrameInfo::estimateStackSize(const MachineFunction &MF) const {
579 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
580 const TargetRegisterInfo *RegInfo = MF.getTarget().getRegisterInfo();
581 unsigned MaxAlign = getMaxAlignment();
584 // This code is very, very similar to PEI::calculateFrameObjectOffsets().
585 // It really should be refactored to share code. Until then, changes
586 // should keep in mind that there's tight coupling between the two.
588 for (int i = getObjectIndexBegin(); i != 0; ++i) {
589 int FixedOff = -getObjectOffset(i);
590 if (FixedOff > Offset) Offset = FixedOff;
592 for (unsigned i = 0, e = getObjectIndexEnd(); i != e; ++i) {
593 if (isDeadObjectIndex(i))
595 Offset += getObjectSize(i);
596 unsigned Align = getObjectAlignment(i);
597 // Adjust to alignment boundary
598 Offset = (Offset+Align-1)/Align*Align;
600 MaxAlign = std::max(Align, MaxAlign);
603 if (adjustsStack() && TFI->hasReservedCallFrame(MF))
604 Offset += getMaxCallFrameSize();
606 // Round up the size to a multiple of the alignment. If the function has
607 // any calls or alloca's, align to the target's StackAlignment value to
608 // ensure that the callee's frame or the alloca data is suitably aligned;
609 // otherwise, for leaf functions, align to the TransientStackAlignment
612 if (adjustsStack() || hasVarSizedObjects() ||
613 (RegInfo->needsStackRealignment(MF) && getObjectIndexEnd() != 0))
614 StackAlign = TFI->getStackAlignment();
616 StackAlign = TFI->getTransientStackAlignment();
618 // If the frame pointer is eliminated, all frame offsets will be relative to
619 // SP not FP. Align to MaxAlign so this works.
620 StackAlign = std::max(StackAlign, MaxAlign);
621 unsigned AlignMask = StackAlign - 1;
622 Offset = (Offset + AlignMask) & ~uint64_t(AlignMask);
624 return (unsigned)Offset;
627 void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{
628 if (Objects.empty()) return;
630 const TargetFrameLowering *FI = MF.getTarget().getFrameLowering();
631 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
633 OS << "Frame Objects:\n";
635 for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
636 const StackObject &SO = Objects[i];
637 OS << " fi#" << (int)(i-NumFixedObjects) << ": ";
638 if (SO.Size == ~0ULL) {
643 OS << "variable sized";
645 OS << "size=" << SO.Size;
646 OS << ", align=" << SO.Alignment;
648 if (i < NumFixedObjects)
650 if (i < NumFixedObjects || SO.SPOffset != -1) {
651 int64_t Off = SO.SPOffset - ValOffset;
652 OS << ", at location [SP";
663 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
664 void MachineFrameInfo::dump(const MachineFunction &MF) const {
669 //===----------------------------------------------------------------------===//
670 // MachineJumpTableInfo implementation
671 //===----------------------------------------------------------------------===//
673 /// getEntrySize - Return the size of each entry in the jump table.
674 unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
675 // The size of a jump table entry is 4 bytes unless the entry is just the
676 // address of a block, in which case it is the pointer size.
677 switch (getEntryKind()) {
678 case MachineJumpTableInfo::EK_BlockAddress:
679 return TD.getPointerSize();
680 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
682 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
683 case MachineJumpTableInfo::EK_LabelDifference32:
684 case MachineJumpTableInfo::EK_Custom32:
686 case MachineJumpTableInfo::EK_Inline:
689 llvm_unreachable("Unknown jump table encoding!");
692 /// getEntryAlignment - Return the alignment of each entry in the jump table.
693 unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
694 // The alignment of a jump table entry is the alignment of int32 unless the
695 // entry is just the address of a block, in which case it is the pointer
697 switch (getEntryKind()) {
698 case MachineJumpTableInfo::EK_BlockAddress:
699 return TD.getPointerABIAlignment();
700 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
701 return TD.getABIIntegerTypeAlignment(64);
702 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
703 case MachineJumpTableInfo::EK_LabelDifference32:
704 case MachineJumpTableInfo::EK_Custom32:
705 return TD.getABIIntegerTypeAlignment(32);
706 case MachineJumpTableInfo::EK_Inline:
709 llvm_unreachable("Unknown jump table encoding!");
712 /// createJumpTableIndex - Create a new jump table entry in the jump table info.
714 unsigned MachineJumpTableInfo::createJumpTableIndex(
715 const std::vector<MachineBasicBlock*> &DestBBs) {
716 assert(!DestBBs.empty() && "Cannot create an empty jump table!");
717 JumpTables.push_back(MachineJumpTableEntry(DestBBs));
718 return JumpTables.size()-1;
721 /// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update
722 /// the jump tables to branch to New instead.
723 bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
724 MachineBasicBlock *New) {
725 assert(Old != New && "Not making a change?");
726 bool MadeChange = false;
727 for (size_t i = 0, e = JumpTables.size(); i != e; ++i)
728 ReplaceMBBInJumpTable(i, Old, New);
732 /// ReplaceMBBInJumpTable - If Old is a target of the jump tables, update
733 /// the jump table to branch to New instead.
734 bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
735 MachineBasicBlock *Old,
736 MachineBasicBlock *New) {
737 assert(Old != New && "Not making a change?");
738 bool MadeChange = false;
739 MachineJumpTableEntry &JTE = JumpTables[Idx];
740 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j)
741 if (JTE.MBBs[j] == Old) {
748 void MachineJumpTableInfo::print(raw_ostream &OS) const {
749 if (JumpTables.empty()) return;
751 OS << "Jump Tables:\n";
753 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
754 OS << " jt#" << i << ": ";
755 for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j)
756 OS << " BB#" << JumpTables[i].MBBs[j]->getNumber();
762 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
763 void MachineJumpTableInfo::dump() const { print(dbgs()); }
767 //===----------------------------------------------------------------------===//
768 // MachineConstantPool implementation
769 //===----------------------------------------------------------------------===//
771 void MachineConstantPoolValue::anchor() { }
773 Type *MachineConstantPoolEntry::getType() const {
774 if (isMachineConstantPoolEntry())
775 return Val.MachineCPVal->getType();
776 return Val.ConstVal->getType();
780 unsigned MachineConstantPoolEntry::getRelocationInfo() const {
781 if (isMachineConstantPoolEntry())
782 return Val.MachineCPVal->getRelocationInfo();
783 return Val.ConstVal->getRelocationInfo();
786 MachineConstantPool::~MachineConstantPool() {
787 for (unsigned i = 0, e = Constants.size(); i != e; ++i)
788 if (Constants[i].isMachineConstantPoolEntry())
789 delete Constants[i].Val.MachineCPVal;
790 for (DenseSet<MachineConstantPoolValue*>::iterator I =
791 MachineCPVsSharingEntries.begin(), E = MachineCPVsSharingEntries.end();
796 /// CanShareConstantPoolEntry - Test whether the given two constants
797 /// can be allocated the same constant pool entry.
798 static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
799 const DataLayout *TD) {
800 // Handle the trivial case quickly.
801 if (A == B) return true;
803 // If they have the same type but weren't the same constant, quickly
805 if (A->getType() == B->getType()) return false;
807 // We can't handle structs or arrays.
808 if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) ||
809 isa<StructType>(B->getType()) || isa<ArrayType>(B->getType()))
812 // For now, only support constants with the same size.
813 uint64_t StoreSize = TD->getTypeStoreSize(A->getType());
814 if (StoreSize != TD->getTypeStoreSize(B->getType()) ||
818 Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8);
820 // Try constant folding a bitcast of both instructions to an integer. If we
821 // get two identical ConstantInt's, then we are good to share them. We use
822 // the constant folding APIs to do this so that we get the benefit of
824 if (isa<PointerType>(A->getType()))
825 A = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy,
826 const_cast<Constant*>(A), TD);
827 else if (A->getType() != IntTy)
828 A = ConstantFoldInstOperands(Instruction::BitCast, IntTy,
829 const_cast<Constant*>(A), TD);
830 if (isa<PointerType>(B->getType()))
831 B = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy,
832 const_cast<Constant*>(B), TD);
833 else if (B->getType() != IntTy)
834 B = ConstantFoldInstOperands(Instruction::BitCast, IntTy,
835 const_cast<Constant*>(B), TD);
840 /// getConstantPoolIndex - Create a new entry in the constant pool or return
841 /// an existing one. User must specify the log2 of the minimum required
842 /// alignment for the object.
844 unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
845 unsigned Alignment) {
846 assert(Alignment && "Alignment must be specified!");
847 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
849 // Check to see if we already have this constant.
851 // FIXME, this could be made much more efficient for large constant pools.
852 for (unsigned i = 0, e = Constants.size(); i != e; ++i)
853 if (!Constants[i].isMachineConstantPoolEntry() &&
854 CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, TD)) {
855 if ((unsigned)Constants[i].getAlignment() < Alignment)
856 Constants[i].Alignment = Alignment;
860 Constants.push_back(MachineConstantPoolEntry(C, Alignment));
861 return Constants.size()-1;
864 unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
865 unsigned Alignment) {
866 assert(Alignment && "Alignment must be specified!");
867 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
869 // Check to see if we already have this constant.
871 // FIXME, this could be made much more efficient for large constant pools.
872 int Idx = V->getExistingMachineCPValue(this, Alignment);
874 MachineCPVsSharingEntries.insert(V);
875 return (unsigned)Idx;
878 Constants.push_back(MachineConstantPoolEntry(V, Alignment));
879 return Constants.size()-1;
882 void MachineConstantPool::print(raw_ostream &OS) const {
883 if (Constants.empty()) return;
885 OS << "Constant Pool:\n";
886 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
887 OS << " cp#" << i << ": ";
888 if (Constants[i].isMachineConstantPoolEntry())
889 Constants[i].Val.MachineCPVal->print(OS);
891 WriteAsOperand(OS, Constants[i].Val.ConstVal, /*PrintType=*/false);
892 OS << ", align=" << Constants[i].getAlignment();
897 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
898 void MachineConstantPool::dump() const { print(dbgs()); }