PPCAsmPrinter.cpp revision dadceedbdb9ef642c49283b632dcfefe48ee4cf4
1//===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly --------=// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file contains a printer that converts from our internal representation 11// of machine-dependent LLVM code to PowerPC assembly language. This printer is 12// the output mechanism used by `llc'. 13// 14// Documentation at http://developer.apple.com/documentation/DeveloperTools/ 15// Reference/Assembler/ASMIntroduction/chapter_1_section_1.html 16// 17//===----------------------------------------------------------------------===// 18 19#define DEBUG_TYPE "asmprinter" 20#include "PPC.h" 21#include "PPCTargetMachine.h" 22#include "PPCSubtarget.h" 23#include "llvm/Constants.h" 24#include "llvm/DerivedTypes.h" 25#include "llvm/Module.h" 26#include "llvm/Assembly/Writer.h" 27#include "llvm/CodeGen/AsmPrinter.h" 28#include "llvm/CodeGen/DwarfWriter.h" 29#include "llvm/CodeGen/MachineDebugInfo.h" 30#include "llvm/CodeGen/MachineFunctionPass.h" 31#include "llvm/CodeGen/MachineInstr.h" 32#include "llvm/Support/Mangler.h" 33#include "llvm/Support/MathExtras.h" 34#include "llvm/Support/CommandLine.h" 35#include "llvm/Support/Debug.h" 36#include "llvm/Support/Compiler.h" 37#include "llvm/Target/TargetAsmInfo.h" 38#include "llvm/Target/MRegisterInfo.h" 39#include "llvm/Target/TargetInstrInfo.h" 40#include "llvm/Target/TargetOptions.h" 41#include "llvm/ADT/Statistic.h" 42#include "llvm/ADT/StringExtras.h" 43#include <iostream> 44#include <set> 45using namespace llvm; 46 47namespace { 48 Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed"); 49 50 struct VISIBILITY_HIDDEN PPCAsmPrinter : public AsmPrinter { 51 std::set<std::string> FnStubs, GVStubs; 52 const PPCSubtarget &Subtarget; 53 54 PPCAsmPrinter(std::ostream &O, TargetMachine &TM, const TargetAsmInfo *T) 55 : AsmPrinter(O, TM, T), Subtarget(TM.getSubtarget<PPCSubtarget>()) { 56 } 57 58 virtual const char *getPassName() const { 59 return "PowerPC Assembly Printer"; 60 } 61 62 PPCTargetMachine &getTM() { 63 return static_cast<PPCTargetMachine&>(TM); 64 } 65 66 unsigned enumRegToMachineReg(unsigned enumReg) { 67 switch (enumReg) { 68 default: assert(0 && "Unhandled register!"); break; 69 case PPC::CR0: return 0; 70 case PPC::CR1: return 1; 71 case PPC::CR2: return 2; 72 case PPC::CR3: return 3; 73 case PPC::CR4: return 4; 74 case PPC::CR5: return 5; 75 case PPC::CR6: return 6; 76 case PPC::CR7: return 7; 77 } 78 abort(); 79 } 80 81 /// printInstruction - This method is automatically generated by tablegen 82 /// from the instruction set description. This method returns true if the 83 /// machine instruction was sufficiently described to print it, otherwise it 84 /// returns false. 85 bool printInstruction(const MachineInstr *MI); 86 87 void printMachineInstruction(const MachineInstr *MI); 88 void printOp(const MachineOperand &MO); 89 90 void printOperand(const MachineInstr *MI, unsigned OpNo) { 91 const MachineOperand &MO = MI->getOperand(OpNo); 92 if (MO.isRegister()) { 93 assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??"); 94 O << TM.getRegisterInfo()->get(MO.getReg()).Name; 95 } else if (MO.isImmediate()) { 96 O << MO.getImmedValue(); 97 } else { 98 printOp(MO); 99 } 100 } 101 102 bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, 103 unsigned AsmVariant, const char *ExtraCode); 104 bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, 105 unsigned AsmVariant, const char *ExtraCode); 106 107 108 void printS5ImmOperand(const MachineInstr *MI, unsigned OpNo) { 109 char value = MI->getOperand(OpNo).getImmedValue(); 110 value = (value << (32-5)) >> (32-5); 111 O << (int)value; 112 } 113 void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo) { 114 unsigned char value = MI->getOperand(OpNo).getImmedValue(); 115 assert(value <= 31 && "Invalid u5imm argument!"); 116 O << (unsigned int)value; 117 } 118 void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo) { 119 unsigned char value = MI->getOperand(OpNo).getImmedValue(); 120 assert(value <= 63 && "Invalid u6imm argument!"); 121 O << (unsigned int)value; 122 } 123 void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo) { 124 O << (short)MI->getOperand(OpNo).getImmedValue(); 125 } 126 void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo) { 127 O << (unsigned short)MI->getOperand(OpNo).getImmedValue(); 128 } 129 void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo) { 130 O << (short)(MI->getOperand(OpNo).getImmedValue()*4); 131 } 132 void printBranchOperand(const MachineInstr *MI, unsigned OpNo) { 133 // Branches can take an immediate operand. This is used by the branch 134 // selection pass to print $+8, an eight byte displacement from the PC. 135 if (MI->getOperand(OpNo).isImmediate()) { 136 O << "$+" << MI->getOperand(OpNo).getImmedValue()*4; 137 } else { 138 printOp(MI->getOperand(OpNo)); 139 } 140 } 141 void printCallOperand(const MachineInstr *MI, unsigned OpNo) { 142 const MachineOperand &MO = MI->getOperand(OpNo); 143 if (TM.getRelocationModel() != Reloc::Static) { 144 if (MO.getType() == MachineOperand::MO_GlobalAddress) { 145 GlobalValue *GV = MO.getGlobal(); 146 if (((GV->isExternal() || GV->hasWeakLinkage() || 147 GV->hasLinkOnceLinkage()))) { 148 // Dynamically-resolved functions need a stub for the function. 149 std::string Name = Mang->getValueName(GV); 150 FnStubs.insert(Name); 151 O << "L" << Name << "$stub"; 152 return; 153 } 154 } 155 if (MO.getType() == MachineOperand::MO_ExternalSymbol) { 156 std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName(); 157 FnStubs.insert(Name); 158 O << "L" << Name << "$stub"; 159 return; 160 } 161 } 162 163 printOp(MI->getOperand(OpNo)); 164 } 165 void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo) { 166 O << (int)MI->getOperand(OpNo).getImmedValue()*4; 167 } 168 void printPICLabel(const MachineInstr *MI, unsigned OpNo) { 169 O << "\"L" << getFunctionNumber() << "$pb\"\n"; 170 O << "\"L" << getFunctionNumber() << "$pb\":"; 171 } 172 void printSymbolHi(const MachineInstr *MI, unsigned OpNo) { 173 if (MI->getOperand(OpNo).isImmediate()) { 174 printS16ImmOperand(MI, OpNo); 175 } else { 176 O << "ha16("; 177 printOp(MI->getOperand(OpNo)); 178 if (TM.getRelocationModel() == Reloc::PIC_) 179 O << "-\"L" << getFunctionNumber() << "$pb\")"; 180 else 181 O << ')'; 182 } 183 } 184 void printSymbolLo(const MachineInstr *MI, unsigned OpNo) { 185 if (MI->getOperand(OpNo).isImmediate()) { 186 printS16ImmOperand(MI, OpNo); 187 } else { 188 O << "lo16("; 189 printOp(MI->getOperand(OpNo)); 190 if (TM.getRelocationModel() == Reloc::PIC_) 191 O << "-\"L" << getFunctionNumber() << "$pb\")"; 192 else 193 O << ')'; 194 } 195 } 196 void printcrbitm(const MachineInstr *MI, unsigned OpNo) { 197 unsigned CCReg = MI->getOperand(OpNo).getReg(); 198 unsigned RegNo = enumRegToMachineReg(CCReg); 199 O << (0x80 >> RegNo); 200 } 201 // The new addressing mode printers. 202 void printMemRegImm(const MachineInstr *MI, unsigned OpNo) { 203 printSymbolLo(MI, OpNo); 204 O << '('; 205 if (MI->getOperand(OpNo+1).isRegister() && 206 MI->getOperand(OpNo+1).getReg() == PPC::R0) 207 O << "0"; 208 else 209 printOperand(MI, OpNo+1); 210 O << ')'; 211 } 212 void printMemRegImmShifted(const MachineInstr *MI, unsigned OpNo) { 213 if (MI->getOperand(OpNo).isImmediate()) 214 printS16X4ImmOperand(MI, OpNo); 215 else 216 printSymbolLo(MI, OpNo); 217 O << '('; 218 if (MI->getOperand(OpNo+1).isRegister() && 219 MI->getOperand(OpNo+1).getReg() == PPC::R0) 220 O << "0"; 221 else 222 printOperand(MI, OpNo+1); 223 O << ')'; 224 } 225 226 void printMemRegReg(const MachineInstr *MI, unsigned OpNo) { 227 // When used as the base register, r0 reads constant zero rather than 228 // the value contained in the register. For this reason, the darwin 229 // assembler requires that we print r0 as 0 (no r) when used as the base. 230 const MachineOperand &MO = MI->getOperand(OpNo); 231 if (MO.getReg() == PPC::R0) 232 O << '0'; 233 else 234 O << TM.getRegisterInfo()->get(MO.getReg()).Name; 235 O << ", "; 236 printOperand(MI, OpNo+1); 237 } 238 239 virtual bool runOnMachineFunction(MachineFunction &F) = 0; 240 virtual bool doFinalization(Module &M) = 0; 241 242 }; 243 244 /// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS 245 /// X 246 struct VISIBILITY_HIDDEN DarwinAsmPrinter : public PPCAsmPrinter { 247 248 DwarfWriter DW; 249 250 DarwinAsmPrinter(std::ostream &O, PPCTargetMachine &TM, 251 const TargetAsmInfo *T) 252 : PPCAsmPrinter(O, TM, T), DW(O, this, T) { 253 bool isPPC64 = Subtarget.isPPC64(); 254 } 255 256 virtual const char *getPassName() const { 257 return "Darwin PPC Assembly Printer"; 258 } 259 260 bool runOnMachineFunction(MachineFunction &F); 261 bool doInitialization(Module &M); 262 bool doFinalization(Module &M); 263 264 void getAnalysisUsage(AnalysisUsage &AU) const { 265 AU.setPreservesAll(); 266 AU.addRequired<MachineDebugInfo>(); 267 PPCAsmPrinter::getAnalysisUsage(AU); 268 } 269 270 }; 271} // end of anonymous namespace 272 273/// createDarwinCodePrinterPass - Returns a pass that prints the PPC assembly 274/// code for a MachineFunction to the given output stream, in a format that the 275/// Darwin assembler can deal with. 276/// 277FunctionPass *llvm::createDarwinCodePrinterPass(std::ostream &o, 278 PPCTargetMachine &tm) { 279 return new DarwinAsmPrinter(o, tm, tm.getTargetAsmInfo()); 280} 281 282// Include the auto-generated portion of the assembly writer 283#include "PPCGenAsmWriter.inc" 284 285void PPCAsmPrinter::printOp(const MachineOperand &MO) { 286 switch (MO.getType()) { 287 case MachineOperand::MO_Immediate: 288 std::cerr << "printOp() does not handle immediate values\n"; 289 abort(); 290 return; 291 292 case MachineOperand::MO_MachineBasicBlock: 293 printBasicBlockLabel(MO.getMachineBasicBlock()); 294 return; 295 case MachineOperand::MO_JumpTableIndex: 296 O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() 297 << '_' << MO.getJumpTableIndex(); 298 // FIXME: PIC relocation model 299 return; 300 case MachineOperand::MO_ConstantPoolIndex: 301 O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() 302 << '_' << MO.getConstantPoolIndex(); 303 return; 304 case MachineOperand::MO_ExternalSymbol: 305 // Computing the address of an external symbol, not calling it. 306 if (TM.getRelocationModel() != Reloc::Static) { 307 std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName(); 308 GVStubs.insert(Name); 309 O << "L" << Name << "$non_lazy_ptr"; 310 return; 311 } 312 O << TAI->getGlobalPrefix() << MO.getSymbolName(); 313 return; 314 case MachineOperand::MO_GlobalAddress: { 315 // Computing the address of a global symbol, not calling it. 316 GlobalValue *GV = MO.getGlobal(); 317 std::string Name = Mang->getValueName(GV); 318 int offset = MO.getOffset(); 319 320 // External or weakly linked global variables need non-lazily-resolved stubs 321 if (TM.getRelocationModel() != Reloc::Static) { 322 if (((GV->isExternal() || GV->hasWeakLinkage() || 323 GV->hasLinkOnceLinkage()))) { 324 GVStubs.insert(Name); 325 O << "L" << Name << "$non_lazy_ptr"; 326 return; 327 } 328 } 329 330 O << Name; 331 return; 332 } 333 334 default: 335 O << "<unknown operand type: " << MO.getType() << ">"; 336 return; 337 } 338} 339 340/// PrintAsmOperand - Print out an operand for an inline asm expression. 341/// 342bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, 343 unsigned AsmVariant, 344 const char *ExtraCode) { 345 // Does this asm operand have a single letter operand modifier? 346 if (ExtraCode && ExtraCode[0]) { 347 if (ExtraCode[1] != 0) return true; // Unknown modifier. 348 349 switch (ExtraCode[0]) { 350 default: return true; // Unknown modifier. 351 case 'L': // Write second word of DImode reference. 352 // Verify that this operand has two consecutive registers. 353 if (!MI->getOperand(OpNo).isRegister() || 354 OpNo+1 == MI->getNumOperands() || 355 !MI->getOperand(OpNo+1).isRegister()) 356 return true; 357 ++OpNo; // Return the high-part. 358 break; 359 } 360 } 361 362 printOperand(MI, OpNo); 363 return false; 364} 365 366bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, 367 unsigned AsmVariant, 368 const char *ExtraCode) { 369 if (ExtraCode && ExtraCode[0]) 370 return true; // Unknown modifier. 371 printMemRegReg(MI, OpNo); 372 return false; 373} 374 375/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to 376/// the current output stream. 377/// 378void PPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) { 379 ++EmittedInsts; 380 381 // Check for slwi/srwi mnemonics. 382 if (MI->getOpcode() == PPC::RLWINM) { 383 bool FoundMnemonic = false; 384 unsigned char SH = MI->getOperand(2).getImmedValue(); 385 unsigned char MB = MI->getOperand(3).getImmedValue(); 386 unsigned char ME = MI->getOperand(4).getImmedValue(); 387 if (SH <= 31 && MB == 0 && ME == (31-SH)) { 388 O << "slwi "; FoundMnemonic = true; 389 } 390 if (SH <= 31 && MB == (32-SH) && ME == 31) { 391 O << "srwi "; FoundMnemonic = true; 392 SH = 32-SH; 393 } 394 if (FoundMnemonic) { 395 printOperand(MI, 0); 396 O << ", "; 397 printOperand(MI, 1); 398 O << ", " << (unsigned int)SH << "\n"; 399 return; 400 } 401 } else if (MI->getOpcode() == PPC::OR || MI->getOpcode() == PPC::OR8) { 402 if (MI->getOperand(1).getReg() == MI->getOperand(2).getReg()) { 403 O << "mr "; 404 printOperand(MI, 0); 405 O << ", "; 406 printOperand(MI, 1); 407 O << "\n"; 408 return; 409 } 410 } 411 412 if (printInstruction(MI)) 413 return; // Printer was automatically generated 414 415 assert(0 && "Unhandled instruction in asm writer!"); 416 abort(); 417 return; 418} 419 420/// runOnMachineFunction - This uses the printMachineInstruction() 421/// method to print assembly for each instruction. 422/// 423bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) { 424 DW.SetDebugInfo(&getAnalysis<MachineDebugInfo>()); 425 426 SetupMachineFunction(MF); 427 O << "\n\n"; 428 429 // Print out constants referenced by the function 430 EmitConstantPool(MF.getConstantPool()); 431 432 // Print out jump tables referenced by the function 433 EmitJumpTableInfo(MF.getJumpTableInfo()); 434 435 // Print out labels for the function. 436 const Function *F = MF.getFunction(); 437 switch (F->getLinkage()) { 438 default: assert(0 && "Unknown linkage type!"); 439 case Function::InternalLinkage: // Symbols default to internal. 440 SwitchToTextSection("\t.text", F); 441 break; 442 case Function::ExternalLinkage: 443 SwitchToTextSection("\t.text", F); 444 O << "\t.globl\t" << CurrentFnName << "\n"; 445 break; 446 case Function::WeakLinkage: 447 case Function::LinkOnceLinkage: 448 SwitchToTextSection( 449 ".section __TEXT,__textcoal_nt,coalesced,pure_instructions", F); 450 O << "\t.globl\t" << CurrentFnName << "\n"; 451 O << "\t.weak_definition\t" << CurrentFnName << "\n"; 452 break; 453 } 454 EmitAlignment(4, F); 455 O << CurrentFnName << ":\n"; 456 457 // Emit pre-function debug information. 458 DW.BeginFunction(&MF); 459 460 // Print out code for the function. 461 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end(); 462 I != E; ++I) { 463 // Print a label for the basic block. 464 if (I != MF.begin()) { 465 printBasicBlockLabel(I, true); 466 O << '\n'; 467 } 468 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end(); 469 II != E; ++II) { 470 // Print the assembly for the instruction. 471 O << "\t"; 472 printMachineInstruction(II); 473 } 474 } 475 476 // Emit post-function debug information. 477 DW.EndFunction(); 478 479 // We didn't modify anything. 480 return false; 481} 482 483 484bool DarwinAsmPrinter::doInitialization(Module &M) { 485 if (Subtarget.isGigaProcessor()) 486 O << "\t.machine ppc970\n"; 487 AsmPrinter::doInitialization(M); 488 489 // Darwin wants symbols to be quoted if they have complex names. 490 Mang->setUseQuotes(true); 491 492 // Emit initial debug information. 493 DW.BeginModule(&M); 494 return false; 495} 496 497bool DarwinAsmPrinter::doFinalization(Module &M) { 498 const TargetData *TD = TM.getTargetData(); 499 500 // Print out module-level global variables here. 501 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 502 I != E; ++I) { 503 if (!I->hasInitializer()) continue; // External global require no code 504 505 // Check to see if this is a special global used by LLVM, if so, emit it. 506 if (EmitSpecialLLVMGlobal(I)) 507 continue; 508 509 std::string name = Mang->getValueName(I); 510 Constant *C = I->getInitializer(); 511 unsigned Size = TD->getTypeSize(C->getType()); 512 unsigned Align = getPreferredAlignmentLog(I); 513 514 if (C->isNullValue() && /* FIXME: Verify correct */ 515 (I->hasInternalLinkage() || I->hasWeakLinkage() || 516 I->hasLinkOnceLinkage() || 517 (I->hasExternalLinkage() && !I->hasSection()))) { 518 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it. 519 if (I->hasExternalLinkage()) { 520 O << "\t.globl " << name << '\n'; 521 O << "\t.zerofill __DATA, __common, " << name << ", " 522 << Size << ", " << Align; 523 } else if (I->hasInternalLinkage()) { 524 SwitchToDataSection("\t.data", I); 525 O << TAI->getLCOMMDirective() << name << "," << Size << "," << Align; 526 } else { 527 SwitchToDataSection("\t.data", I); 528 O << ".comm " << name << "," << Size; 529 } 530 O << "\t\t; '" << I->getName() << "'\n"; 531 } else { 532 switch (I->getLinkage()) { 533 case GlobalValue::LinkOnceLinkage: 534 case GlobalValue::WeakLinkage: 535 O << "\t.globl " << name << '\n' 536 << "\t.weak_definition " << name << '\n'; 537 SwitchToDataSection(".section __DATA,__datacoal_nt,coalesced", I); 538 break; 539 case GlobalValue::AppendingLinkage: 540 // FIXME: appending linkage variables should go into a section of 541 // their name or something. For now, just emit them as external. 542 case GlobalValue::ExternalLinkage: 543 // If external or appending, declare as a global symbol 544 O << "\t.globl " << name << "\n"; 545 // FALL THROUGH 546 case GlobalValue::InternalLinkage: 547 SwitchToDataSection("\t.data", I); 548 break; 549 default: 550 std::cerr << "Unknown linkage type!"; 551 abort(); 552 } 553 554 EmitAlignment(Align, I); 555 O << name << ":\t\t\t\t; '" << I->getName() << "'\n"; 556 EmitGlobalConstant(C); 557 O << '\n'; 558 } 559 } 560 561 bool isPPC64 = TD->getPointerSizeInBits() == 64; 562 563 // Output stubs for dynamically-linked functions 564 if (TM.getRelocationModel() == Reloc::PIC_) { 565 for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end(); 566 i != e; ++i) { 567 SwitchToTextSection(".section __TEXT,__picsymbolstub1,symbol_stubs," 568 "pure_instructions,32", 0); 569 EmitAlignment(4); 570 O << "L" << *i << "$stub:\n"; 571 O << "\t.indirect_symbol " << *i << "\n"; 572 O << "\tmflr r0\n"; 573 O << "\tbcl 20,31,L0$" << *i << "\n"; 574 O << "L0$" << *i << ":\n"; 575 O << "\tmflr r11\n"; 576 O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n"; 577 O << "\tmtlr r0\n"; 578 if (isPPC64) 579 O << "\tldu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n"; 580 else 581 O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n"; 582 O << "\tmtctr r12\n"; 583 O << "\tbctr\n"; 584 SwitchToDataSection(".lazy_symbol_pointer", 0); 585 O << "L" << *i << "$lazy_ptr:\n"; 586 O << "\t.indirect_symbol " << *i << "\n"; 587 if (isPPC64) 588 O << "\t.quad dyld_stub_binding_helper\n"; 589 else 590 O << "\t.long dyld_stub_binding_helper\n"; 591 } 592 } else { 593 for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end(); 594 i != e; ++i) { 595 SwitchToTextSection(".section __TEXT,__symbol_stub1,symbol_stubs," 596 "pure_instructions,16", 0); 597 EmitAlignment(4); 598 O << "L" << *i << "$stub:\n"; 599 O << "\t.indirect_symbol " << *i << "\n"; 600 O << "\tlis r11,ha16(L" << *i << "$lazy_ptr)\n"; 601 if (isPPC64) 602 O << "\tldu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n"; 603 else 604 O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n"; 605 O << "\tmtctr r12\n"; 606 O << "\tbctr\n"; 607 SwitchToDataSection(".lazy_symbol_pointer", 0); 608 O << "L" << *i << "$lazy_ptr:\n"; 609 O << "\t.indirect_symbol " << *i << "\n"; 610 if (isPPC64) 611 O << "\t.quad dyld_stub_binding_helper\n"; 612 else 613 O << "\t.long dyld_stub_binding_helper\n"; 614 } 615 } 616 617 O << "\n"; 618 619 // Output stubs for external and common global variables. 620 if (GVStubs.begin() != GVStubs.end()) { 621 SwitchToDataSection(".non_lazy_symbol_pointer", 0); 622 for (std::set<std::string>::iterator I = GVStubs.begin(), 623 E = GVStubs.end(); I != E; ++I) { 624 O << "L" << *I << "$non_lazy_ptr:\n"; 625 O << "\t.indirect_symbol " << *I << "\n"; 626 if (isPPC64) 627 O << "\t.quad\t0\n"; 628 else 629 O << "\t.long\t0\n"; 630 631 } 632 } 633 634 // Emit initial debug information. 635 DW.EndModule(); 636 637 // Funny Darwin hack: This flag tells the linker that no global symbols 638 // contain code that falls through to other global symbols (e.g. the obvious 639 // implementation of multiple entry points). If this doesn't occur, the 640 // linker can safely perform dead code stripping. Since LLVM never generates 641 // code that does this, it is always safe to set. 642 if (Subtarget.isDarwin()) 643 O << "\t.subsections_via_symbols\n"; 644 645 AsmPrinter::doFinalization(M); 646 return false; // success 647} 648 649