MachineFunction.cpp revision 015f228861ef9b337366f92f637d4e8d624bb006
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/Function.h" 18#include "llvm/CodeGen/MachineConstantPool.h" 19#include "llvm/CodeGen/MachineFunctionPass.h" 20#include "llvm/CodeGen/MachineFrameInfo.h" 21#include "llvm/CodeGen/MachineInstr.h" 22#include "llvm/CodeGen/MachineJumpTableInfo.h" 23#include "llvm/CodeGen/MachineModuleInfo.h" 24#include "llvm/CodeGen/MachineRegisterInfo.h" 25#include "llvm/CodeGen/Passes.h" 26#include "llvm/MC/MCAsmInfo.h" 27#include "llvm/MC/MCContext.h" 28#include "llvm/Analysis/ConstantFolding.h" 29#include "llvm/Analysis/DebugInfo.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->setMaxAlignment(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 FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo); 88 ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool); 89 90 if (JumpTableInfo) { 91 JumpTableInfo->~MachineJumpTableInfo(); 92 Allocator.Deallocate(JumpTableInfo); 93 } 94} 95 96/// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it 97/// does already exist, allocate one. 98MachineJumpTableInfo *MachineFunction:: 99getOrCreateJumpTableInfo(unsigned EntryKind) { 100 if (JumpTableInfo) return JumpTableInfo; 101 102 JumpTableInfo = new (Allocator) 103 MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind); 104 return JumpTableInfo; 105} 106 107/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 108/// recomputes them. This guarantees that the MBB numbers are sequential, 109/// dense, and match the ordering of the blocks within the function. If a 110/// specific MachineBasicBlock is specified, only that block and those after 111/// it are renumbered. 112void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 113 if (empty()) { MBBNumbering.clear(); return; } 114 MachineFunction::iterator MBBI, E = end(); 115 if (MBB == 0) 116 MBBI = begin(); 117 else 118 MBBI = MBB; 119 120 // Figure out the block number this should have. 121 unsigned BlockNo = 0; 122 if (MBBI != begin()) 123 BlockNo = prior(MBBI)->getNumber()+1; 124 125 for (; MBBI != E; ++MBBI, ++BlockNo) { 126 if (MBBI->getNumber() != (int)BlockNo) { 127 // Remove use of the old number. 128 if (MBBI->getNumber() != -1) { 129 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 130 "MBB number mismatch!"); 131 MBBNumbering[MBBI->getNumber()] = 0; 132 } 133 134 // If BlockNo is already taken, set that block's number to -1. 135 if (MBBNumbering[BlockNo]) 136 MBBNumbering[BlockNo]->setNumber(-1); 137 138 MBBNumbering[BlockNo] = MBBI; 139 MBBI->setNumber(BlockNo); 140 } 141 } 142 143 // Okay, all the blocks are renumbered. If we have compactified the block 144 // numbering, shrink MBBNumbering now. 145 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 146 MBBNumbering.resize(BlockNo); 147} 148 149/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 150/// of `new MachineInstr'. 151/// 152MachineInstr * 153MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID, 154 DebugLoc DL, bool NoImp) { 155 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 156 MachineInstr(MCID, DL, NoImp); 157} 158 159/// CloneMachineInstr - Create a new MachineInstr which is a copy of the 160/// 'Orig' instruction, identical in all ways except the instruction 161/// has no parent, prev, or next. 162/// 163MachineInstr * 164MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 165 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 166 MachineInstr(*this, *Orig); 167} 168 169/// DeleteMachineInstr - Delete the given MachineInstr. 170/// 171void 172MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 173 MI->~MachineInstr(); 174 InstructionRecycler.Deallocate(Allocator, MI); 175} 176 177/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 178/// instead of `new MachineBasicBlock'. 179/// 180MachineBasicBlock * 181MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 182 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 183 MachineBasicBlock(*this, bb); 184} 185 186/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 187/// 188void 189MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 190 assert(MBB->getParent() == this && "MBB parent mismatch!"); 191 MBB->~MachineBasicBlock(); 192 BasicBlockRecycler.Deallocate(Allocator, MBB); 193} 194 195MachineMemOperand * 196MachineFunction::getMachineMemOperand(MachinePointerInfo PtrInfo, unsigned f, 197 uint64_t s, unsigned base_alignment, 198 const MDNode *TBAAInfo) { 199 return new (Allocator) MachineMemOperand(PtrInfo, f, s, base_alignment, 200 TBAAInfo); 201} 202 203MachineMemOperand * 204MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO, 205 int64_t Offset, uint64_t Size) { 206 return new (Allocator) 207 MachineMemOperand(MachinePointerInfo(MMO->getValue(), 208 MMO->getOffset()+Offset), 209 MMO->getFlags(), Size, 210 MMO->getBaseAlignment(), 0); 211} 212 213MachineInstr::mmo_iterator 214MachineFunction::allocateMemRefsArray(unsigned long Num) { 215 return Allocator.Allocate<MachineMemOperand *>(Num); 216} 217 218std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator> 219MachineFunction::extractLoadMemRefs(MachineInstr::mmo_iterator Begin, 220 MachineInstr::mmo_iterator End) { 221 // Count the number of load mem refs. 222 unsigned Num = 0; 223 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) 224 if ((*I)->isLoad()) 225 ++Num; 226 227 // Allocate a new array and populate it with the load information. 228 MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num); 229 unsigned Index = 0; 230 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) { 231 if ((*I)->isLoad()) { 232 if (!(*I)->isStore()) 233 // Reuse the MMO. 234 Result[Index] = *I; 235 else { 236 // Clone the MMO and unset the store flag. 237 MachineMemOperand *JustLoad = 238 getMachineMemOperand((*I)->getPointerInfo(), 239 (*I)->getFlags() & ~MachineMemOperand::MOStore, 240 (*I)->getSize(), (*I)->getBaseAlignment(), 241 (*I)->getTBAAInfo()); 242 Result[Index] = JustLoad; 243 } 244 ++Index; 245 } 246 } 247 return std::make_pair(Result, Result + Num); 248} 249 250std::pair<MachineInstr::mmo_iterator, MachineInstr::mmo_iterator> 251MachineFunction::extractStoreMemRefs(MachineInstr::mmo_iterator Begin, 252 MachineInstr::mmo_iterator End) { 253 // Count the number of load mem refs. 254 unsigned Num = 0; 255 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) 256 if ((*I)->isStore()) 257 ++Num; 258 259 // Allocate a new array and populate it with the store information. 260 MachineInstr::mmo_iterator Result = allocateMemRefsArray(Num); 261 unsigned Index = 0; 262 for (MachineInstr::mmo_iterator I = Begin; I != End; ++I) { 263 if ((*I)->isStore()) { 264 if (!(*I)->isLoad()) 265 // Reuse the MMO. 266 Result[Index] = *I; 267 else { 268 // Clone the MMO and unset the load flag. 269 MachineMemOperand *JustStore = 270 getMachineMemOperand((*I)->getPointerInfo(), 271 (*I)->getFlags() & ~MachineMemOperand::MOLoad, 272 (*I)->getSize(), (*I)->getBaseAlignment(), 273 (*I)->getTBAAInfo()); 274 Result[Index] = JustStore; 275 } 276 ++Index; 277 } 278 } 279 return std::make_pair(Result, Result + Num); 280} 281 282void MachineFunction::dump() const { 283 print(dbgs()); 284} 285 286void MachineFunction::print(raw_ostream &OS, SlotIndexes *Indexes) const { 287 OS << "# Machine code for function " << Fn->getName() << ":\n"; 288 289 // Print Frame Information 290 FrameInfo->print(*this, OS); 291 292 // Print JumpTable Information 293 if (JumpTableInfo) 294 JumpTableInfo->print(OS); 295 296 // Print Constant Pool 297 ConstantPool->print(OS); 298 299 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 300 301 if (RegInfo && !RegInfo->livein_empty()) { 302 OS << "Function Live Ins: "; 303 for (MachineRegisterInfo::livein_iterator 304 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 305 OS << PrintReg(I->first, TRI); 306 if (I->second) 307 OS << " in " << PrintReg(I->second, TRI); 308 if (llvm::next(I) != E) 309 OS << ", "; 310 } 311 OS << '\n'; 312 } 313 if (RegInfo && !RegInfo->liveout_empty()) { 314 OS << "Function Live Outs:"; 315 for (MachineRegisterInfo::liveout_iterator 316 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 317 OS << ' ' << PrintReg(*I, TRI); 318 OS << '\n'; 319 } 320 321 for (const_iterator BB = begin(), E = end(); BB != E; ++BB) { 322 OS << '\n'; 323 BB->print(OS, Indexes); 324 } 325 326 OS << "\n# End machine code for function " << Fn->getName() << ".\n\n"; 327} 328 329namespace llvm { 330 template<> 331 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 332 333 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {} 334 335 static std::string getGraphName(const MachineFunction *F) { 336 return "CFG for '" + F->getFunction()->getName().str() + "' function"; 337 } 338 339 std::string getNodeLabel(const MachineBasicBlock *Node, 340 const MachineFunction *Graph) { 341 std::string OutStr; 342 { 343 raw_string_ostream OSS(OutStr); 344 345 if (isSimple()) { 346 OSS << "BB#" << Node->getNumber(); 347 if (const BasicBlock *BB = Node->getBasicBlock()) 348 OSS << ": " << BB->getName(); 349 } else 350 Node->print(OSS); 351 } 352 353 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 354 355 // Process string output to make it nicer... 356 for (unsigned i = 0; i != OutStr.length(); ++i) 357 if (OutStr[i] == '\n') { // Left justify 358 OutStr[i] = '\\'; 359 OutStr.insert(OutStr.begin()+i+1, 'l'); 360 } 361 return OutStr; 362 } 363 }; 364} 365 366void MachineFunction::viewCFG() const 367{ 368#ifndef NDEBUG 369 ViewGraph(this, "mf" + getFunction()->getName()); 370#else 371 errs() << "MachineFunction::viewCFG is only available in debug builds on " 372 << "systems with Graphviz or gv!\n"; 373#endif // NDEBUG 374} 375 376void MachineFunction::viewCFGOnly() const 377{ 378#ifndef NDEBUG 379 ViewGraph(this, "mf" + getFunction()->getName(), true); 380#else 381 errs() << "MachineFunction::viewCFGOnly is only available in debug builds on " 382 << "systems with Graphviz or gv!\n"; 383#endif // NDEBUG 384} 385 386/// addLiveIn - Add the specified physical register as a live-in value and 387/// create a corresponding virtual register for it. 388unsigned MachineFunction::addLiveIn(unsigned PReg, 389 const TargetRegisterClass *RC) { 390 MachineRegisterInfo &MRI = getRegInfo(); 391 unsigned VReg = MRI.getLiveInVirtReg(PReg); 392 if (VReg) { 393 assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!"); 394 return VReg; 395 } 396 VReg = MRI.createVirtualRegister(RC); 397 MRI.addLiveIn(PReg, VReg); 398 return VReg; 399} 400 401/// getJTISymbol - Return the MCSymbol for the specified non-empty jump table. 402/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a 403/// normal 'L' label is returned. 404MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx, 405 bool isLinkerPrivate) const { 406 assert(JumpTableInfo && "No jump tables"); 407 408 assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!"); 409 const MCAsmInfo &MAI = *getTarget().getMCAsmInfo(); 410 411 const char *Prefix = isLinkerPrivate ? MAI.getLinkerPrivateGlobalPrefix() : 412 MAI.getPrivateGlobalPrefix(); 413 SmallString<60> Name; 414 raw_svector_ostream(Name) 415 << Prefix << "JTI" << getFunctionNumber() << '_' << JTI; 416 return Ctx.GetOrCreateSymbol(Name.str()); 417} 418 419/// getPICBaseSymbol - Return a function-local symbol to represent the PIC 420/// base. 421MCSymbol *MachineFunction::getPICBaseSymbol() const { 422 const MCAsmInfo &MAI = *Target.getMCAsmInfo(); 423 return Ctx.GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix())+ 424 Twine(getFunctionNumber())+"$pb"); 425} 426 427//===----------------------------------------------------------------------===// 428// MachineFrameInfo implementation 429//===----------------------------------------------------------------------===// 430 431/// CreateFixedObject - Create a new object at a fixed location on the stack. 432/// All fixed objects should be created before other objects are created for 433/// efficiency. By default, fixed objects are immutable. This returns an 434/// index with a negative value. 435/// 436int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 437 bool Immutable) { 438 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 439 // The alignment of the frame index can be determined from its offset from 440 // the incoming frame position. If the frame object is at offset 32 and 441 // the stack is guaranteed to be 16-byte aligned, then we know that the 442 // object is 16-byte aligned. 443 unsigned StackAlign = TFI.getStackAlignment(); 444 unsigned Align = MinAlign(SPOffset, StackAlign); 445 Objects.insert(Objects.begin(), StackObject(Size, Align, SPOffset, Immutable, 446 /*isSS*/false, false)); 447 return -++NumFixedObjects; 448} 449 450 451BitVector 452MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const { 453 assert(MBB && "MBB must be valid"); 454 const MachineFunction *MF = MBB->getParent(); 455 assert(MF && "MBB must be part of a MachineFunction"); 456 const TargetMachine &TM = MF->getTarget(); 457 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 458 BitVector BV(TRI->getNumRegs()); 459 460 // Before CSI is calculated, no registers are considered pristine. They can be 461 // freely used and PEI will make sure they are saved. 462 if (!isCalleeSavedInfoValid()) 463 return BV; 464 465 for (const uint16_t *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR) 466 BV.set(*CSR); 467 468 // The entry MBB always has all CSRs pristine. 469 if (MBB == &MF->front()) 470 return BV; 471 472 // On other MBBs the saved CSRs are not pristine. 473 const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo(); 474 for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(), 475 E = CSI.end(); I != E; ++I) 476 BV.reset(I->getReg()); 477 478 return BV; 479} 480 481 482void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{ 483 if (Objects.empty()) return; 484 485 const TargetFrameLowering *FI = MF.getTarget().getFrameLowering(); 486 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 487 488 OS << "Frame Objects:\n"; 489 490 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 491 const StackObject &SO = Objects[i]; 492 OS << " fi#" << (int)(i-NumFixedObjects) << ": "; 493 if (SO.Size == ~0ULL) { 494 OS << "dead\n"; 495 continue; 496 } 497 if (SO.Size == 0) 498 OS << "variable sized"; 499 else 500 OS << "size=" << SO.Size; 501 OS << ", align=" << SO.Alignment; 502 503 if (i < NumFixedObjects) 504 OS << ", fixed"; 505 if (i < NumFixedObjects || SO.SPOffset != -1) { 506 int64_t Off = SO.SPOffset - ValOffset; 507 OS << ", at location [SP"; 508 if (Off > 0) 509 OS << "+" << Off; 510 else if (Off < 0) 511 OS << Off; 512 OS << "]"; 513 } 514 OS << "\n"; 515 } 516} 517 518void MachineFrameInfo::dump(const MachineFunction &MF) const { 519 print(MF, dbgs()); 520} 521 522//===----------------------------------------------------------------------===// 523// MachineJumpTableInfo implementation 524//===----------------------------------------------------------------------===// 525 526/// getEntrySize - Return the size of each entry in the jump table. 527unsigned MachineJumpTableInfo::getEntrySize(const TargetData &TD) const { 528 // The size of a jump table entry is 4 bytes unless the entry is just the 529 // address of a block, in which case it is the pointer size. 530 switch (getEntryKind()) { 531 case MachineJumpTableInfo::EK_BlockAddress: 532 return TD.getPointerSize(); 533 case MachineJumpTableInfo::EK_GPRel64BlockAddress: 534 return 8; 535 case MachineJumpTableInfo::EK_GPRel32BlockAddress: 536 case MachineJumpTableInfo::EK_LabelDifference32: 537 case MachineJumpTableInfo::EK_Custom32: 538 return 4; 539 case MachineJumpTableInfo::EK_Inline: 540 return 0; 541 } 542 llvm_unreachable("Unknown jump table encoding!"); 543} 544 545/// getEntryAlignment - Return the alignment of each entry in the jump table. 546unsigned MachineJumpTableInfo::getEntryAlignment(const TargetData &TD) const { 547 // The alignment of a jump table entry is the alignment of int32 unless the 548 // entry is just the address of a block, in which case it is the pointer 549 // alignment. 550 switch (getEntryKind()) { 551 case MachineJumpTableInfo::EK_BlockAddress: 552 return TD.getPointerABIAlignment(); 553 case MachineJumpTableInfo::EK_GPRel64BlockAddress: 554 return TD.getABIIntegerTypeAlignment(64); 555 case MachineJumpTableInfo::EK_GPRel32BlockAddress: 556 case MachineJumpTableInfo::EK_LabelDifference32: 557 case MachineJumpTableInfo::EK_Custom32: 558 return TD.getABIIntegerTypeAlignment(32); 559 case MachineJumpTableInfo::EK_Inline: 560 return 1; 561 } 562 llvm_unreachable("Unknown jump table encoding!"); 563} 564 565/// createJumpTableIndex - Create a new jump table entry in the jump table info. 566/// 567unsigned MachineJumpTableInfo::createJumpTableIndex( 568 const std::vector<MachineBasicBlock*> &DestBBs) { 569 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 570 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 571 return JumpTables.size()-1; 572} 573 574/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update 575/// the jump tables to branch to New instead. 576bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old, 577 MachineBasicBlock *New) { 578 assert(Old != New && "Not making a change?"); 579 bool MadeChange = false; 580 for (size_t i = 0, e = JumpTables.size(); i != e; ++i) 581 ReplaceMBBInJumpTable(i, Old, New); 582 return MadeChange; 583} 584 585/// ReplaceMBBInJumpTable - If Old is a target of the jump tables, update 586/// the jump table to branch to New instead. 587bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx, 588 MachineBasicBlock *Old, 589 MachineBasicBlock *New) { 590 assert(Old != New && "Not making a change?"); 591 bool MadeChange = false; 592 MachineJumpTableEntry &JTE = JumpTables[Idx]; 593 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j) 594 if (JTE.MBBs[j] == Old) { 595 JTE.MBBs[j] = New; 596 MadeChange = true; 597 } 598 return MadeChange; 599} 600 601void MachineJumpTableInfo::print(raw_ostream &OS) const { 602 if (JumpTables.empty()) return; 603 604 OS << "Jump Tables:\n"; 605 606 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 607 OS << " jt#" << i << ": "; 608 for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j) 609 OS << " BB#" << JumpTables[i].MBBs[j]->getNumber(); 610 } 611 612 OS << '\n'; 613} 614 615void MachineJumpTableInfo::dump() const { print(dbgs()); } 616 617 618//===----------------------------------------------------------------------===// 619// MachineConstantPool implementation 620//===----------------------------------------------------------------------===// 621 622void MachineConstantPoolValue::anchor() { } 623 624Type *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 for (DenseSet<MachineConstantPoolValue*>::iterator I = 642 MachineCPVsSharingEntries.begin(), E = MachineCPVsSharingEntries.end(); 643 I != E; ++I) 644 delete *I; 645} 646 647/// CanShareConstantPoolEntry - Test whether the given two constants 648/// can be allocated the same constant pool entry. 649static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B, 650 const TargetData *TD) { 651 // Handle the trivial case quickly. 652 if (A == B) return true; 653 654 // If they have the same type but weren't the same constant, quickly 655 // reject them. 656 if (A->getType() == B->getType()) return false; 657 658 // We can't handle structs or arrays. 659 if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) || 660 isa<StructType>(B->getType()) || isa<ArrayType>(B->getType())) 661 return false; 662 663 // For now, only support constants with the same size. 664 uint64_t StoreSize = TD->getTypeStoreSize(A->getType()); 665 if (StoreSize != TD->getTypeStoreSize(B->getType()) || 666 StoreSize > 128) 667 return false; 668 669 Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8); 670 671 // Try constant folding a bitcast of both instructions to an integer. If we 672 // get two identical ConstantInt's, then we are good to share them. We use 673 // the constant folding APIs to do this so that we get the benefit of 674 // TargetData. 675 if (isa<PointerType>(A->getType())) 676 A = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy, 677 const_cast<Constant*>(A), TD); 678 else if (A->getType() != IntTy) 679 A = ConstantFoldInstOperands(Instruction::BitCast, IntTy, 680 const_cast<Constant*>(A), TD); 681 if (isa<PointerType>(B->getType())) 682 B = ConstantFoldInstOperands(Instruction::PtrToInt, IntTy, 683 const_cast<Constant*>(B), TD); 684 else if (B->getType() != IntTy) 685 B = ConstantFoldInstOperands(Instruction::BitCast, IntTy, 686 const_cast<Constant*>(B), TD); 687 688 return A == B; 689} 690 691/// getConstantPoolIndex - Create a new entry in the constant pool or return 692/// an existing one. User must specify the log2 of the minimum required 693/// alignment for the object. 694/// 695unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C, 696 unsigned Alignment) { 697 assert(Alignment && "Alignment must be specified!"); 698 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 699 700 // Check to see if we already have this constant. 701 // 702 // FIXME, this could be made much more efficient for large constant pools. 703 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 704 if (!Constants[i].isMachineConstantPoolEntry() && 705 CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, TD)) { 706 if ((unsigned)Constants[i].getAlignment() < Alignment) 707 Constants[i].Alignment = Alignment; 708 return i; 709 } 710 711 Constants.push_back(MachineConstantPoolEntry(C, Alignment)); 712 return Constants.size()-1; 713} 714 715unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 716 unsigned Alignment) { 717 assert(Alignment && "Alignment must be specified!"); 718 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 719 720 // Check to see if we already have this constant. 721 // 722 // FIXME, this could be made much more efficient for large constant pools. 723 int Idx = V->getExistingMachineCPValue(this, Alignment); 724 if (Idx != -1) { 725 MachineCPVsSharingEntries.insert(V); 726 return (unsigned)Idx; 727 } 728 729 Constants.push_back(MachineConstantPoolEntry(V, Alignment)); 730 return Constants.size()-1; 731} 732 733void MachineConstantPool::print(raw_ostream &OS) const { 734 if (Constants.empty()) return; 735 736 OS << "Constant Pool:\n"; 737 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 738 OS << " cp#" << i << ": "; 739 if (Constants[i].isMachineConstantPoolEntry()) 740 Constants[i].Val.MachineCPVal->print(OS); 741 else 742 OS << *(Value*)Constants[i].Val.ConstVal; 743 OS << ", align=" << Constants[i].getAlignment(); 744 OS << "\n"; 745 } 746} 747 748void MachineConstantPool::dump() const { print(dbgs()); } 749