MachineFunction.cpp revision c05d30601ced172b55be81bb529df6be91d6ae15
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/DebugInfo.h" 18#include "llvm/Function.h" 19#include "llvm/CodeGen/MachineConstantPool.h" 20#include "llvm/CodeGen/MachineFunctionPass.h" 21#include "llvm/CodeGen/MachineFrameInfo.h" 22#include "llvm/CodeGen/MachineInstr.h" 23#include "llvm/CodeGen/MachineJumpTableInfo.h" 24#include "llvm/CodeGen/MachineModuleInfo.h" 25#include "llvm/CodeGen/MachineRegisterInfo.h" 26#include "llvm/CodeGen/Passes.h" 27#include "llvm/MC/MCAsmInfo.h" 28#include "llvm/MC/MCContext.h" 29#include "llvm/Analysis/ConstantFolding.h" 30#include "llvm/Support/Debug.h" 31#include "llvm/Target/TargetData.h" 32#include "llvm/Target/TargetLowering.h" 33#include "llvm/Target/TargetMachine.h" 34#include "llvm/Target/TargetFrameLowering.h" 35#include "llvm/ADT/SmallString.h" 36#include "llvm/ADT/STLExtras.h" 37#include "llvm/Support/GraphWriter.h" 38#include "llvm/Support/raw_ostream.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 if (Fn->hasFnAttr(Attribute::StackAlignment)) 63 FrameInfo->ensureMaxAlignment(Attribute::getStackAlignmentFromAttrs( 64 Fn->getAttributes().getFnAttributes())); 65 ConstantPool = new (Allocator) MachineConstantPool(TM.getTargetData()); 66 Alignment = TM.getTargetLowering()->getMinFunctionAlignment(); 67 // FIXME: Shouldn't use pref alignment if explicit alignment is set on Fn. 68 if (!Fn->hasFnAttr(Attribute::OptimizeForSize)) 69 Alignment = std::max(Alignment, 70 TM.getTargetLowering()->getPrefFunctionAlignment()); 71 FunctionNumber = FunctionNum; 72 JumpTableInfo = 0; 73} 74 75MachineFunction::~MachineFunction() { 76 BasicBlocks.clear(); 77 InstructionRecycler.clear(Allocator); 78 BasicBlockRecycler.clear(Allocator); 79 if (RegInfo) { 80 RegInfo->~MachineRegisterInfo(); 81 Allocator.Deallocate(RegInfo); 82 } 83 if (MFInfo) { 84 MFInfo->~MachineFunctionInfo(); 85 Allocator.Deallocate(MFInfo); 86 } 87 88 FrameInfo->~MachineFrameInfo(); 89 Allocator.Deallocate(FrameInfo); 90 91 ConstantPool->~MachineConstantPool(); 92 Allocator.Deallocate(ConstantPool); 93 94 if (JumpTableInfo) { 95 JumpTableInfo->~MachineJumpTableInfo(); 96 Allocator.Deallocate(JumpTableInfo); 97 } 98} 99 100/// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it 101/// does already exist, allocate one. 102MachineJumpTableInfo *MachineFunction:: 103getOrCreateJumpTableInfo(unsigned EntryKind) { 104 if (JumpTableInfo) return JumpTableInfo; 105 106 JumpTableInfo = new (Allocator) 107 MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind); 108 return JumpTableInfo; 109} 110 111/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 112/// recomputes them. This guarantees that the MBB numbers are sequential, 113/// dense, and match the ordering of the blocks within the function. If a 114/// specific MachineBasicBlock is specified, only that block and those after 115/// it are renumbered. 116void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 117 if (empty()) { MBBNumbering.clear(); return; } 118 MachineFunction::iterator MBBI, E = end(); 119 if (MBB == 0) 120 MBBI = begin(); 121 else 122 MBBI = MBB; 123 124 // Figure out the block number this should have. 125 unsigned BlockNo = 0; 126 if (MBBI != begin()) 127 BlockNo = prior(MBBI)->getNumber()+1; 128 129 for (; MBBI != E; ++MBBI, ++BlockNo) { 130 if (MBBI->getNumber() != (int)BlockNo) { 131 // Remove use of the old number. 132 if (MBBI->getNumber() != -1) { 133 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 134 "MBB number mismatch!"); 135 MBBNumbering[MBBI->getNumber()] = 0; 136 } 137 138 // If BlockNo is already taken, set that block's number to -1. 139 if (MBBNumbering[BlockNo]) 140 MBBNumbering[BlockNo]->setNumber(-1); 141 142 MBBNumbering[BlockNo] = MBBI; 143 MBBI->setNumber(BlockNo); 144 } 145 } 146 147 // Okay, all the blocks are renumbered. If we have compactified the block 148 // numbering, shrink MBBNumbering now. 149 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 150 MBBNumbering.resize(BlockNo); 151} 152 153/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 154/// of `new MachineInstr'. 155/// 156MachineInstr * 157MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID, 158 DebugLoc DL, bool NoImp) { 159 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 160 MachineInstr(MCID, DL, NoImp); 161} 162 163/// CloneMachineInstr - Create a new MachineInstr which is a copy of the 164/// 'Orig' instruction, identical in all ways except the instruction 165/// has no parent, prev, or next. 166/// 167MachineInstr * 168MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 169 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 170 MachineInstr(*this, *Orig); 171} 172 173/// DeleteMachineInstr - Delete the given MachineInstr. 174/// 175void 176MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 177 MI->~MachineInstr(); 178 InstructionRecycler.Deallocate(Allocator, MI); 179} 180 181/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 182/// instead of `new MachineBasicBlock'. 183/// 184MachineBasicBlock * 185MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 186 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 187 MachineBasicBlock(*this, bb); 188} 189 190/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 191/// 192void 193MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 194 assert(MBB->getParent() == this && "MBB parent mismatch!"); 195 MBB->~MachineBasicBlock(); 196 BasicBlockRecycler.Deallocate(Allocator, MBB); 197} 198 199MachineMemOperand * 200MachineFunction::getMachineMemOperand(MachinePointerInfo PtrInfo, unsigned f, 201 uint64_t s, unsigned base_alignment, 202 const MDNode *TBAAInfo, 203 const MDNode *Ranges) { 204 return new (Allocator) MachineMemOperand(PtrInfo, f, s, base_alignment, 205 TBAAInfo, Ranges); 206} 207 208MachineMemOperand * 209MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO, 210 int64_t Offset, uint64_t Size) { 211 return new (Allocator) 212 MachineMemOperand(MachinePointerInfo(MMO->getValue(), 213 MMO->getOffset()+Offset), 214 MMO->getFlags(), Size, 215 MMO->getBaseAlignment(), 0); 216} 217 218MachineInstr::mmo_iterator 219MachineFunction::allocateMemRefsArray(unsigned long Num) { 220 return Allocator.Allocate<MachineMemOperand *>(Num); 221} 222 223std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator> 224MachineFunction::extractLoadMemRefs(MachineInstr::mmo_iterator Begin, 225 MachineInstr::mmo_iterator End) { 226 // Count the number of load mem refs. 227 unsigned Num = 0; 228 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) 229 if ((*I)->isLoad()) 230 ++Num; 231 232 // Allocate a new array and populate it with the load information. 233 MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num); 234 unsigned Index = 0; 235 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) { 236 if ((*I)->isLoad()) { 237 if (!(*I)->isStore()) 238 // Reuse the MMO. 239 Result[Index] = *I; 240 else { 241 // Clone the MMO and unset the store flag. 242 MachineMemOperand *JustLoad = 243 getMachineMemOperand((*I)->getPointerInfo(), 244 (*I)->getFlags() & ~MachineMemOperand::MOStore, 245 (*I)->getSize(), (*I)->getBaseAlignment(), 246 (*I)->getTBAAInfo()); 247 Result[Index] = JustLoad; 248 } 249 ++Index; 250 } 251 } 252 return std::make_pair(Result, Result + Num); 253} 254 255std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator> 256MachineFunction::extractStoreMemRefs(MachineInstr::mmo_iterator Begin, 257 MachineInstr::mmo_iterator End) { 258 // Count the number of load mem refs. 259 unsigned Num = 0; 260 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) 261 if ((*I)->isStore()) 262 ++Num; 263 264 // Allocate a new array and populate it with the store information. 265 MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num); 266 unsigned Index = 0; 267 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) { 268 if ((*I)->isStore()) { 269 if (!(*I)->isLoad()) 270 // Reuse the MMO. 271 Result[Index] = *I; 272 else { 273 // Clone the MMO and unset the load flag. 274 MachineMemOperand *JustStore = 275 getMachineMemOperand((*I)->getPointerInfo(), 276 (*I)->getFlags() & ~MachineMemOperand::MOLoad, 277 (*I)->getSize(), (*I)->getBaseAlignment(), 278 (*I)->getTBAAInfo()); 279 Result[Index] = JustStore; 280 } 281 ++Index; 282 } 283 } 284 return std::make_pair(Result, Result + Num); 285} 286 287void MachineFunction::dump() const { 288 print(dbgs()); 289} 290 291StringRef MachineFunction::getName() const { 292 assert(getFunction() && "No function!"); 293 return getFunction()->getName(); 294} 295 296void MachineFunction::print(raw_ostream &OS, SlotIndexes *Indexes) const { 297 OS << "# Machine code for function " << getName() << ": "; 298 if (RegInfo) { 299 OS << (RegInfo->isSSA() ? "SSA" : "Post SSA"); 300 if (!RegInfo->tracksLiveness()) 301 OS << ", not tracking liveness"; 302 } 303 OS << '\n'; 304 305 // Print Frame Information 306 FrameInfo->print(*this, OS); 307 308 // Print JumpTable Information 309 if (JumpTableInfo) 310 JumpTableInfo->print(OS); 311 312 // Print Constant Pool 313 ConstantPool->print(OS); 314 315 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 316 317 if (RegInfo && !RegInfo->livein_empty()) { 318 OS << "Function Live Ins: "; 319 for (MachineRegisterInfo::livein_iterator 320 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 321 OS << PrintReg(I->first, TRI); 322 if (I->second) 323 OS << " in " << PrintReg(I->second, TRI); 324 if (llvm::next(I) != E) 325 OS << ", "; 326 } 327 OS << '\n'; 328 } 329 if (RegInfo && !RegInfo->liveout_empty()) { 330 OS << "Function Live Outs:"; 331 for (MachineRegisterInfo::liveout_iterator 332 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 333 OS << ' ' << PrintReg(*I, TRI); 334 OS << '\n'; 335 } 336 337 for (const_iterator BB = begin(), E = end(); BB != E; ++BB) { 338 OS << '\n'; 339 BB->print(OS, Indexes); 340 } 341 342 OS << "\n# End machine code for function " << getName() << ".\n\n"; 343} 344 345namespace llvm { 346 template<> 347 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 348 349 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {} 350 351 static std::string getGraphName(const MachineFunction *F) { 352 return "CFG for '" + F->getName().str() + "' function"; 353 } 354 355 std::string getNodeLabel(const MachineBasicBlock *Node, 356 const MachineFunction *Graph) { 357 std::string OutStr; 358 { 359 raw_string_ostream OSS(OutStr); 360 361 if (isSimple()) { 362 OSS << "BB#" << Node->getNumber(); 363 if (const BasicBlock *BB = Node->getBasicBlock()) 364 OSS << ": " << BB->getName(); 365 } else 366 Node->print(OSS); 367 } 368 369 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 370 371 // Process string output to make it nicer... 372 for (unsigned i = 0; i != OutStr.length(); ++i) 373 if (OutStr[i] == '\n') { // Left justify 374 OutStr[i] = '\\'; 375 OutStr.insert(OutStr.begin()+i+1, 'l'); 376 } 377 return OutStr; 378 } 379 }; 380} 381 382void MachineFunction::viewCFG() const 383{ 384#ifndef NDEBUG 385 ViewGraph(this, "mf" + getName()); 386#else 387 errs() << "MachineFunction::viewCFG is only available in debug builds on " 388 << "systems with Graphviz or gv!\n"; 389#endif // NDEBUG 390} 391 392void MachineFunction::viewCFGOnly() const 393{ 394#ifndef NDEBUG 395 ViewGraph(this, "mf" + getName(), true); 396#else 397 errs() << "MachineFunction::viewCFGOnly is only available in debug builds on " 398 << "systems with Graphviz or gv!\n"; 399#endif // NDEBUG 400} 401 402/// addLiveIn - Add the specified physical register as a live-in value and 403/// create a corresponding virtual register for it. 404unsigned MachineFunction::addLiveIn(unsigned PReg, 405 const TargetRegisterClass *RC) { 406 MachineRegisterInfo &MRI = getRegInfo(); 407 unsigned VReg = MRI.getLiveInVirtReg(PReg); 408 if (VReg) { 409 assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!"); 410 return VReg; 411 } 412 VReg = MRI.createVirtualRegister(RC); 413 MRI.addLiveIn(PReg, VReg); 414 return VReg; 415} 416 417/// getJTISymbol - Return the MCSymbol for the specified non-empty jump table. 418/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a 419/// normal 'L' label is returned. 420MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx, 421 bool isLinkerPrivate) const { 422 assert(JumpTableInfo && "No jump tables"); 423 assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!"); 424 const MCAsmInfo &MAI = *getTarget().getMCAsmInfo(); 425 426 const char *Prefix = isLinkerPrivate ? MAI.getLinkerPrivateGlobalPrefix() : 427 MAI.getPrivateGlobalPrefix(); 428 SmallString<60> Name; 429 raw_svector_ostream(Name) 430 << Prefix << "JTI" << getFunctionNumber() << '_' << JTI; 431 return Ctx.GetOrCreateSymbol(Name.str()); 432} 433 434/// getPICBaseSymbol - Return a function-local symbol to represent the PIC 435/// base. 436MCSymbol *MachineFunction::getPICBaseSymbol() const { 437 const MCAsmInfo &MAI = *Target.getMCAsmInfo(); 438 return Ctx.GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix())+ 439 Twine(getFunctionNumber())+"$pb"); 440} 441 442//===----------------------------------------------------------------------===// 443// MachineFrameInfo implementation 444//===----------------------------------------------------------------------===// 445 446/// CreateFixedObject - Create a new object at a fixed location on the stack. 447/// All fixed objects should be created before other objects are created for 448/// efficiency. By default, fixed objects are immutable. This returns an 449/// index with a negative value. 450/// 451int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 452 bool Immutable) { 453 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 454 // The alignment of the frame index can be determined from its offset from 455 // the incoming frame position. If the frame object is at offset 32 and 456 // the stack is guaranteed to be 16-byte aligned, then we know that the 457 // object is 16-byte aligned. 458 unsigned StackAlign = TFI.getStackAlignment(); 459 unsigned Align = MinAlign(SPOffset, StackAlign); 460 Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable, 461 /*isSS*/ false, 462 /*NeedSP*/ false, 463 /*Alloca*/ 0)); 464 return -++NumFixedObjects; 465} 466 467 468BitVector 469MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const { 470 assert(MBB && "MBB must be valid"); 471 const MachineFunction *MF = MBB->getParent(); 472 assert(MF && "MBB must be part of a MachineFunction"); 473 const TargetMachine &TM = MF->getTarget(); 474 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 475 BitVector BV(TRI->getNumRegs()); 476 477 // Before CSI is calculated, no registers are considered pristine. They can be 478 // freely used and PEI will make sure they are saved. 479 if (!isCalleeSavedInfoValid()) 480 return BV; 481 482 for (const uint16_t *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR) 483 BV.set(*CSR); 484 485 // The entry MBB always has all CSRs pristine. 486 if (MBB == &MF->front()) 487 return BV; 488 489 // On other MBBs the saved CSRs are not pristine. 490 const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo(); 491 for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(), 492 E = CSI.end(); I != E; ++I) 493 BV.reset(I->getReg()); 494 495 return BV; 496} 497 498 499void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{ 500 if (Objects.empty()) return; 501 502 const TargetFrameLowering *FI = MF.getTarget().getFrameLowering(); 503 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 504 505 OS << "Frame Objects:\n"; 506 507 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 508 const StackObject &SO = Objects[i]; 509 OS << " fi#" << (int)(i-NumFixedObjects) << ": "; 510 if (SO.Size == ~0ULL) { 511 OS << "dead\n"; 512 continue; 513 } 514 if (SO.Size == 0) 515 OS << "variable sized"; 516 else 517 OS << "size=" << SO.Size; 518 OS << ", align=" << SO.Alignment; 519 520 if (i < NumFixedObjects) 521 OS << ", fixed"; 522 if (i < NumFixedObjects || SO.SPOffset != -1) { 523 int64_t Off = SO.SPOffset - ValOffset; 524 OS << ", at location [SP"; 525 if (Off > 0) 526 OS << "+" << Off; 527 else if (Off < 0) 528 OS << Off; 529 OS << "]"; 530 } 531 OS << "\n"; 532 } 533} 534 535void MachineFrameInfo::dump(const MachineFunction &MF) const { 536 print(MF, dbgs()); 537} 538 539//===----------------------------------------------------------------------===// 540// MachineJumpTableInfo implementation 541//===----------------------------------------------------------------------===// 542 543/// getEntrySize - Return the size of each entry in the jump table. 544unsigned MachineJumpTableInfo::getEntrySize(const TargetData &TD) const { 545 // The size of a jump table entry is 4 bytes unless the entry is just the 546 // address of a block, in which case it is the pointer size. 547 switch (getEntryKind()) { 548 case MachineJumpTableInfo::EK_BlockAddress: 549 return TD.getPointerSize(); 550 case MachineJumpTableInfo::EK_GPRel64BlockAddress: 551 return 8; 552 case MachineJumpTableInfo::EK_GPRel32BlockAddress: 553 case MachineJumpTableInfo::EK_LabelDifference32: 554 case MachineJumpTableInfo::EK_Custom32: 555 return 4; 556 case MachineJumpTableInfo::EK_Inline: 557 return 0; 558 } 559 llvm_unreachable("Unknown jump table encoding!"); 560} 561 562/// getEntryAlignment - Return the alignment of each entry in the jump table. 563unsigned MachineJumpTableInfo::getEntryAlignment(const TargetData &TD) const { 564 // The alignment of a jump table entry is the alignment of int32 unless the 565 // entry is just the address of a block, in which case it is the pointer 566 // alignment. 567 switch (getEntryKind()) { 568 case MachineJumpTableInfo::EK_BlockAddress: 569 return TD.getPointerABIAlignment(); 570 case MachineJumpTableInfo::EK_GPRel64BlockAddress: 571 return TD.getABIIntegerTypeAlignment(64); 572 case MachineJumpTableInfo::EK_GPRel32BlockAddress: 573 case MachineJumpTableInfo::EK_LabelDifference32: 574 case MachineJumpTableInfo::EK_Custom32: 575 return TD.getABIIntegerTypeAlignment(32); 576 case MachineJumpTableInfo::EK_Inline: 577 return 1; 578 } 579 llvm_unreachable("Unknown jump table encoding!"); 580} 581 582/// createJumpTableIndex - Create a new jump table entry in the jump table info. 583/// 584unsigned MachineJumpTableInfo::createJumpTableIndex( 585 const std::vector<MachineBasicBlock*> &DestBBs) { 586 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 587 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 588 return JumpTables.size()-1; 589} 590 591/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update 592/// the jump tables to branch to New instead. 593bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old, 594 MachineBasicBlock *New) { 595 assert(Old != New && "Not making a change?"); 596 bool MadeChange = false; 597 for (size_t i = 0, e = JumpTables.size(); i != e; ++i) 598 ReplaceMBBInJumpTable(i, Old, New); 599 return MadeChange; 600} 601 602/// ReplaceMBBInJumpTable - If Old is a target of the jump tables, update 603/// the jump table to branch to New instead. 604bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx, 605 MachineBasicBlock *Old, 606 MachineBasicBlock *New) { 607 assert(Old != New && "Not making a change?"); 608 bool MadeChange = false; 609 MachineJumpTableEntry &JTE = JumpTables[Idx]; 610 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j) 611 if (JTE.MBBs[j] == Old) { 612 JTE.MBBs[j] = New; 613 MadeChange = true; 614 } 615 return MadeChange; 616} 617 618void MachineJumpTableInfo::print(raw_ostream &OS) const { 619 if (JumpTables.empty()) return; 620 621 OS << "Jump Tables:\n"; 622 623 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 624 OS << " jt#" << i << ": "; 625 for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j) 626 OS << " BB#" << JumpTables[i].MBBs[j]->getNumber(); 627 } 628 629 OS << '\n'; 630} 631 632void MachineJumpTableInfo::dump() const { print(dbgs()); } 633 634 635//===----------------------------------------------------------------------===// 636// MachineConstantPool implementation 637//===----------------------------------------------------------------------===// 638 639void MachineConstantPoolValue::anchor() { } 640 641Type *MachineConstantPoolEntry::getType() const { 642 if (isMachineConstantPoolEntry()) 643 return Val.MachineCPVal->getType(); 644 return Val.ConstVal->getType(); 645} 646 647 648unsigned MachineConstantPoolEntry::getRelocationInfo() const { 649 if (isMachineConstantPoolEntry()) 650 return Val.MachineCPVal->getRelocationInfo(); 651 return Val.ConstVal->getRelocationInfo(); 652} 653 654MachineConstantPool::~MachineConstantPool() { 655 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 656 if (Constants[i].isMachineConstantPoolEntry()) 657 delete Constants[i].Val.MachineCPVal; 658 for (DenseSet<MachineConstantPoolValue*>::iterator I = 659 MachineCPVsSharingEntries.begin(), E = MachineCPVsSharingEntries.end(); 660 I != E; ++I) 661 delete *I; 662} 663 664/// CanShareConstantPoolEntry - Test whether the given two constants 665/// can be allocated the same constant pool entry. 666static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B, 667 const TargetData *TD) { 668 // Handle the trivial case quickly. 669 if (A == B) return true; 670 671 // If they have the same type but weren't the same constant, quickly 672 // reject them. 673 if (A->getType() == B->getType()) return false; 674 675 // We can't handle structs or arrays. 676 if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) || 677 isa<StructType>(B->getType()) || isa<ArrayType>(B->getType())) 678 return false; 679 680 // For now, only support constants with the same size. 681 uint64_t StoreSize = TD->getTypeStoreSize(A->getType()); 682 if (StoreSize != TD->getTypeStoreSize(B->getType()) || 683 StoreSize > 128) 684 return false; 685 686 Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8); 687 688 // Try constant folding a bitcast of both instructions to an integer. If we 689 // get two identical ConstantInt's, then we are good to share them. We use 690 // the constant folding APIs to do this so that we get the benefit of 691 // TargetData. 692 if (isa<PointerType>(A->getType())) 693 A = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy, 694 const_cast<Constant*>(A), TD); 695 else if (A->getType() != IntTy) 696 A = ConstantFoldInstOperands(Instruction::BitCast, IntTy, 697 const_cast<Constant*>(A), TD); 698 if (isa<PointerType>(B->getType())) 699 B = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy, 700 const_cast<Constant*>(B), TD); 701 else if (B->getType() != IntTy) 702 B = ConstantFoldInstOperands(Instruction::BitCast, IntTy, 703 const_cast<Constant*>(B), TD); 704 705 return A == B; 706} 707 708/// getConstantPoolIndex - Create a new entry in the constant pool or return 709/// an existing one. User must specify the log2 of the minimum required 710/// alignment for the object. 711/// 712unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C, 713 unsigned Alignment) { 714 assert(Alignment && "Alignment must be specified!"); 715 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 716 717 // Check to see if we already have this constant. 718 // 719 // FIXME, this could be made much more efficient for large constant pools. 720 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 721 if (!Constants[i].isMachineConstantPoolEntry() && 722 CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, TD)) { 723 if ((unsigned)Constants[i].getAlignment() < Alignment) 724 Constants[i].Alignment = Alignment; 725 return i; 726 } 727 728 Constants.push_back(MachineConstantPoolEntry(C, Alignment)); 729 return Constants.size()-1; 730} 731 732unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 733 unsigned Alignment) { 734 assert(Alignment && "Alignment must be specified!"); 735 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 736 737 // Check to see if we already have this constant. 738 // 739 // FIXME, this could be made much more efficient for large constant pools. 740 int Idx = V->getExistingMachineCPValue(this, Alignment); 741 if (Idx != -1) { 742 MachineCPVsSharingEntries.insert(V); 743 return (unsigned)Idx; 744 } 745 746 Constants.push_back(MachineConstantPoolEntry(V, Alignment)); 747 return Constants.size()-1; 748} 749 750void MachineConstantPool::print(raw_ostream &OS) const { 751 if (Constants.empty()) return; 752 753 OS << "Constant Pool:\n"; 754 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 755 OS << " cp#" << i << ": "; 756 if (Constants[i].isMachineConstantPoolEntry()) 757 Constants[i].Val.MachineCPVal->print(OS); 758 else 759 OS << *(const Value*)Constants[i].Val.ConstVal; 760 OS << ", align=" << Constants[i].getAlignment(); 761 OS << "\n"; 762 } 763} 764 765void MachineConstantPool::dump() const { print(dbgs()); } 766