1 //===-- ARMAsmPrinter.cpp - Print machine code to an ARM .s file ----------===// 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 // This file contains a printer that converts from our internal representation 11 // of machine-dependent LLVM code to GAS-format ARM assembly language. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "ARMAsmPrinter.h" 16 #include "ARM.h" 17 #include "ARMConstantPoolValue.h" 18 #include "ARMFPUName.h" 19 #include "ARMMachineFunctionInfo.h" 20 #include "ARMTargetMachine.h" 21 #include "ARMTargetObjectFile.h" 22 #include "InstPrinter/ARMInstPrinter.h" 23 #include "MCTargetDesc/ARMAddressingModes.h" 24 #include "MCTargetDesc/ARMMCExpr.h" 25 #include "llvm/ADT/SetVector.h" 26 #include "llvm/ADT/SmallString.h" 27 #include "llvm/CodeGen/MachineFunctionPass.h" 28 #include "llvm/CodeGen/MachineJumpTableInfo.h" 29 #include "llvm/CodeGen/MachineModuleInfoImpls.h" 30 #include "llvm/IR/Constants.h" 31 #include "llvm/IR/DataLayout.h" 32 #include "llvm/IR/DebugInfo.h" 33 #include "llvm/IR/Mangler.h" 34 #include "llvm/IR/Module.h" 35 #include "llvm/IR/Type.h" 36 #include "llvm/MC/MCAsmInfo.h" 37 #include "llvm/MC/MCAssembler.h" 38 #include "llvm/MC/MCContext.h" 39 #include "llvm/MC/MCELFStreamer.h" 40 #include "llvm/MC/MCInst.h" 41 #include "llvm/MC/MCInstBuilder.h" 42 #include "llvm/MC/MCObjectStreamer.h" 43 #include "llvm/MC/MCSectionMachO.h" 44 #include "llvm/MC/MCStreamer.h" 45 #include "llvm/MC/MCSymbol.h" 46 #include "llvm/Support/ARMBuildAttributes.h" 47 #include "llvm/Support/COFF.h" 48 #include "llvm/Support/CommandLine.h" 49 #include "llvm/Support/Debug.h" 50 #include "llvm/Support/ELF.h" 51 #include "llvm/Support/ErrorHandling.h" 52 #include "llvm/Support/TargetRegistry.h" 53 #include "llvm/Support/raw_ostream.h" 54 #include "llvm/Target/TargetMachine.h" 55 #include <cctype> 56 using namespace llvm; 57 58 #define DEBUG_TYPE "asm-printer" 59 60 void ARMAsmPrinter::EmitFunctionBodyEnd() { 61 // Make sure to terminate any constant pools that were at the end 62 // of the function. 63 if (!InConstantPool) 64 return; 65 InConstantPool = false; 66 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd); 67 } 68 69 void ARMAsmPrinter::EmitFunctionEntryLabel() { 70 if (AFI->isThumbFunction()) { 71 OutStreamer.EmitAssemblerFlag(MCAF_Code16); 72 OutStreamer.EmitThumbFunc(CurrentFnSym); 73 } 74 75 OutStreamer.EmitLabel(CurrentFnSym); 76 } 77 78 void ARMAsmPrinter::EmitXXStructor(const Constant *CV) { 79 uint64_t Size = 80 TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(CV->getType()); 81 assert(Size && "C++ constructor pointer had zero size!"); 82 83 const GlobalValue *GV = dyn_cast<GlobalValue>(CV->stripPointerCasts()); 84 assert(GV && "C++ constructor pointer was not a GlobalValue!"); 85 86 const MCExpr *E = MCSymbolRefExpr::Create(GetARMGVSymbol(GV, 87 ARMII::MO_NO_FLAG), 88 (Subtarget->isTargetELF() 89 ? MCSymbolRefExpr::VK_ARM_TARGET1 90 : MCSymbolRefExpr::VK_None), 91 OutContext); 92 93 OutStreamer.EmitValue(E, Size); 94 } 95 96 /// runOnMachineFunction - This uses the EmitInstruction() 97 /// method to print assembly for each instruction. 98 /// 99 bool ARMAsmPrinter::runOnMachineFunction(MachineFunction &MF) { 100 AFI = MF.getInfo<ARMFunctionInfo>(); 101 MCP = MF.getConstantPool(); 102 103 SetupMachineFunction(MF); 104 105 if (Subtarget->isTargetCOFF()) { 106 bool Internal = MF.getFunction()->hasInternalLinkage(); 107 COFF::SymbolStorageClass Scl = Internal ? COFF::IMAGE_SYM_CLASS_STATIC 108 : COFF::IMAGE_SYM_CLASS_EXTERNAL; 109 int Type = COFF::IMAGE_SYM_DTYPE_FUNCTION << COFF::SCT_COMPLEX_TYPE_SHIFT; 110 111 OutStreamer.BeginCOFFSymbolDef(CurrentFnSym); 112 OutStreamer.EmitCOFFSymbolStorageClass(Scl); 113 OutStreamer.EmitCOFFSymbolType(Type); 114 OutStreamer.EndCOFFSymbolDef(); 115 } 116 117 // Have common code print out the function header with linkage info etc. 118 EmitFunctionHeader(); 119 120 // Emit the rest of the function body. 121 EmitFunctionBody(); 122 123 // We didn't modify anything. 124 return false; 125 } 126 127 void ARMAsmPrinter::printOperand(const MachineInstr *MI, int OpNum, 128 raw_ostream &O, const char *Modifier) { 129 const MachineOperand &MO = MI->getOperand(OpNum); 130 unsigned TF = MO.getTargetFlags(); 131 132 switch (MO.getType()) { 133 default: llvm_unreachable("<unknown operand type>"); 134 case MachineOperand::MO_Register: { 135 unsigned Reg = MO.getReg(); 136 assert(TargetRegisterInfo::isPhysicalRegister(Reg)); 137 assert(!MO.getSubReg() && "Subregs should be eliminated!"); 138 if(ARM::GPRPairRegClass.contains(Reg)) { 139 const MachineFunction &MF = *MI->getParent()->getParent(); 140 const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo(); 141 Reg = TRI->getSubReg(Reg, ARM::gsub_0); 142 } 143 O << ARMInstPrinter::getRegisterName(Reg); 144 break; 145 } 146 case MachineOperand::MO_Immediate: { 147 int64_t Imm = MO.getImm(); 148 O << '#'; 149 if ((Modifier && strcmp(Modifier, "lo16") == 0) || 150 (TF == ARMII::MO_LO16)) 151 O << ":lower16:"; 152 else if ((Modifier && strcmp(Modifier, "hi16") == 0) || 153 (TF == ARMII::MO_HI16)) 154 O << ":upper16:"; 155 O << Imm; 156 break; 157 } 158 case MachineOperand::MO_MachineBasicBlock: 159 O << *MO.getMBB()->getSymbol(); 160 return; 161 case MachineOperand::MO_GlobalAddress: { 162 const GlobalValue *GV = MO.getGlobal(); 163 if ((Modifier && strcmp(Modifier, "lo16") == 0) || 164 (TF & ARMII::MO_LO16)) 165 O << ":lower16:"; 166 else if ((Modifier && strcmp(Modifier, "hi16") == 0) || 167 (TF & ARMII::MO_HI16)) 168 O << ":upper16:"; 169 O << *GetARMGVSymbol(GV, TF); 170 171 printOffset(MO.getOffset(), O); 172 if (TF == ARMII::MO_PLT) 173 O << "(PLT)"; 174 break; 175 } 176 case MachineOperand::MO_ConstantPoolIndex: 177 O << *GetCPISymbol(MO.getIndex()); 178 break; 179 } 180 } 181 182 //===--------------------------------------------------------------------===// 183 184 MCSymbol *ARMAsmPrinter:: 185 GetARMJTIPICJumpTableLabel2(unsigned uid, unsigned uid2) const { 186 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout(); 187 SmallString<60> Name; 188 raw_svector_ostream(Name) << DL->getPrivateGlobalPrefix() << "JTI" 189 << getFunctionNumber() << '_' << uid << '_' << uid2; 190 return OutContext.GetOrCreateSymbol(Name.str()); 191 } 192 193 194 MCSymbol *ARMAsmPrinter::GetARMSJLJEHLabel() const { 195 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout(); 196 SmallString<60> Name; 197 raw_svector_ostream(Name) << DL->getPrivateGlobalPrefix() << "SJLJEH" 198 << getFunctionNumber(); 199 return OutContext.GetOrCreateSymbol(Name.str()); 200 } 201 202 bool ARMAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum, 203 unsigned AsmVariant, const char *ExtraCode, 204 raw_ostream &O) { 205 // Does this asm operand have a single letter operand modifier? 206 if (ExtraCode && ExtraCode[0]) { 207 if (ExtraCode[1] != 0) return true; // Unknown modifier. 208 209 switch (ExtraCode[0]) { 210 default: 211 // See if this is a generic print operand 212 return AsmPrinter::PrintAsmOperand(MI, OpNum, AsmVariant, ExtraCode, O); 213 case 'a': // Print as a memory address. 214 if (MI->getOperand(OpNum).isReg()) { 215 O << "[" 216 << ARMInstPrinter::getRegisterName(MI->getOperand(OpNum).getReg()) 217 << "]"; 218 return false; 219 } 220 // Fallthrough 221 case 'c': // Don't print "#" before an immediate operand. 222 if (!MI->getOperand(OpNum).isImm()) 223 return true; 224 O << MI->getOperand(OpNum).getImm(); 225 return false; 226 case 'P': // Print a VFP double precision register. 227 case 'q': // Print a NEON quad precision register. 228 printOperand(MI, OpNum, O); 229 return false; 230 case 'y': // Print a VFP single precision register as indexed double. 231 if (MI->getOperand(OpNum).isReg()) { 232 unsigned Reg = MI->getOperand(OpNum).getReg(); 233 const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); 234 // Find the 'd' register that has this 's' register as a sub-register, 235 // and determine the lane number. 236 for (MCSuperRegIterator SR(Reg, TRI); SR.isValid(); ++SR) { 237 if (!ARM::DPRRegClass.contains(*SR)) 238 continue; 239 bool Lane0 = TRI->getSubReg(*SR, ARM::ssub_0) == Reg; 240 O << ARMInstPrinter::getRegisterName(*SR) << (Lane0 ? "[0]" : "[1]"); 241 return false; 242 } 243 } 244 return true; 245 case 'B': // Bitwise inverse of integer or symbol without a preceding #. 246 if (!MI->getOperand(OpNum).isImm()) 247 return true; 248 O << ~(MI->getOperand(OpNum).getImm()); 249 return false; 250 case 'L': // The low 16 bits of an immediate constant. 251 if (!MI->getOperand(OpNum).isImm()) 252 return true; 253 O << (MI->getOperand(OpNum).getImm() & 0xffff); 254 return false; 255 case 'M': { // A register range suitable for LDM/STM. 256 if (!MI->getOperand(OpNum).isReg()) 257 return true; 258 const MachineOperand &MO = MI->getOperand(OpNum); 259 unsigned RegBegin = MO.getReg(); 260 // This takes advantage of the 2 operand-ness of ldm/stm and that we've 261 // already got the operands in registers that are operands to the 262 // inline asm statement. 263 O << "{"; 264 if (ARM::GPRPairRegClass.contains(RegBegin)) { 265 const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); 266 unsigned Reg0 = TRI->getSubReg(RegBegin, ARM::gsub_0); 267 O << ARMInstPrinter::getRegisterName(Reg0) << ", "; 268 RegBegin = TRI->getSubReg(RegBegin, ARM::gsub_1); 269 } 270 O << ARMInstPrinter::getRegisterName(RegBegin); 271 272 // FIXME: The register allocator not only may not have given us the 273 // registers in sequence, but may not be in ascending registers. This 274 // will require changes in the register allocator that'll need to be 275 // propagated down here if the operands change. 276 unsigned RegOps = OpNum + 1; 277 while (MI->getOperand(RegOps).isReg()) { 278 O << ", " 279 << ARMInstPrinter::getRegisterName(MI->getOperand(RegOps).getReg()); 280 RegOps++; 281 } 282 283 O << "}"; 284 285 return false; 286 } 287 case 'R': // The most significant register of a pair. 288 case 'Q': { // The least significant register of a pair. 289 if (OpNum == 0) 290 return true; 291 const MachineOperand &FlagsOP = MI->getOperand(OpNum - 1); 292 if (!FlagsOP.isImm()) 293 return true; 294 unsigned Flags = FlagsOP.getImm(); 295 296 // This operand may not be the one that actually provides the register. If 297 // it's tied to a previous one then we should refer instead to that one 298 // for registers and their classes. 299 unsigned TiedIdx; 300 if (InlineAsm::isUseOperandTiedToDef(Flags, TiedIdx)) { 301 for (OpNum = InlineAsm::MIOp_FirstOperand; TiedIdx; --TiedIdx) { 302 unsigned OpFlags = MI->getOperand(OpNum).getImm(); 303 OpNum += InlineAsm::getNumOperandRegisters(OpFlags) + 1; 304 } 305 Flags = MI->getOperand(OpNum).getImm(); 306 307 // Later code expects OpNum to be pointing at the register rather than 308 // the flags. 309 OpNum += 1; 310 } 311 312 unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags); 313 unsigned RC; 314 InlineAsm::hasRegClassConstraint(Flags, RC); 315 if (RC == ARM::GPRPairRegClassID) { 316 if (NumVals != 1) 317 return true; 318 const MachineOperand &MO = MI->getOperand(OpNum); 319 if (!MO.isReg()) 320 return true; 321 const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); 322 unsigned Reg = TRI->getSubReg(MO.getReg(), ExtraCode[0] == 'Q' ? 323 ARM::gsub_0 : ARM::gsub_1); 324 O << ARMInstPrinter::getRegisterName(Reg); 325 return false; 326 } 327 if (NumVals != 2) 328 return true; 329 unsigned RegOp = ExtraCode[0] == 'Q' ? OpNum : OpNum + 1; 330 if (RegOp >= MI->getNumOperands()) 331 return true; 332 const MachineOperand &MO = MI->getOperand(RegOp); 333 if (!MO.isReg()) 334 return true; 335 unsigned Reg = MO.getReg(); 336 O << ARMInstPrinter::getRegisterName(Reg); 337 return false; 338 } 339 340 case 'e': // The low doubleword register of a NEON quad register. 341 case 'f': { // The high doubleword register of a NEON quad register. 342 if (!MI->getOperand(OpNum).isReg()) 343 return true; 344 unsigned Reg = MI->getOperand(OpNum).getReg(); 345 if (!ARM::QPRRegClass.contains(Reg)) 346 return true; 347 const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); 348 unsigned SubReg = TRI->getSubReg(Reg, ExtraCode[0] == 'e' ? 349 ARM::dsub_0 : ARM::dsub_1); 350 O << ARMInstPrinter::getRegisterName(SubReg); 351 return false; 352 } 353 354 // This modifier is not yet supported. 355 case 'h': // A range of VFP/NEON registers suitable for VLD1/VST1. 356 return true; 357 case 'H': { // The highest-numbered register of a pair. 358 const MachineOperand &MO = MI->getOperand(OpNum); 359 if (!MO.isReg()) 360 return true; 361 const MachineFunction &MF = *MI->getParent()->getParent(); 362 const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo(); 363 unsigned Reg = MO.getReg(); 364 if(!ARM::GPRPairRegClass.contains(Reg)) 365 return false; 366 Reg = TRI->getSubReg(Reg, ARM::gsub_1); 367 O << ARMInstPrinter::getRegisterName(Reg); 368 return false; 369 } 370 } 371 } 372 373 printOperand(MI, OpNum, O); 374 return false; 375 } 376 377 bool ARMAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, 378 unsigned OpNum, unsigned AsmVariant, 379 const char *ExtraCode, 380 raw_ostream &O) { 381 // Does this asm operand have a single letter operand modifier? 382 if (ExtraCode && ExtraCode[0]) { 383 if (ExtraCode[1] != 0) return true; // Unknown modifier. 384 385 switch (ExtraCode[0]) { 386 case 'A': // A memory operand for a VLD1/VST1 instruction. 387 default: return true; // Unknown modifier. 388 case 'm': // The base register of a memory operand. 389 if (!MI->getOperand(OpNum).isReg()) 390 return true; 391 O << ARMInstPrinter::getRegisterName(MI->getOperand(OpNum).getReg()); 392 return false; 393 } 394 } 395 396 const MachineOperand &MO = MI->getOperand(OpNum); 397 assert(MO.isReg() && "unexpected inline asm memory operand"); 398 O << "[" << ARMInstPrinter::getRegisterName(MO.getReg()) << "]"; 399 return false; 400 } 401 402 static bool isThumb(const MCSubtargetInfo& STI) { 403 return (STI.getFeatureBits() & ARM::ModeThumb) != 0; 404 } 405 406 void ARMAsmPrinter::emitInlineAsmEnd(const MCSubtargetInfo &StartInfo, 407 const MCSubtargetInfo *EndInfo) const { 408 // If either end mode is unknown (EndInfo == NULL) or different than 409 // the start mode, then restore the start mode. 410 const bool WasThumb = isThumb(StartInfo); 411 if (!EndInfo || WasThumb != isThumb(*EndInfo)) { 412 OutStreamer.EmitAssemblerFlag(WasThumb ? MCAF_Code16 : MCAF_Code32); 413 } 414 } 415 416 void ARMAsmPrinter::EmitStartOfAsmFile(Module &M) { 417 if (Subtarget->isTargetMachO()) { 418 Reloc::Model RelocM = TM.getRelocationModel(); 419 if (RelocM == Reloc::PIC_ || RelocM == Reloc::DynamicNoPIC) { 420 // Declare all the text sections up front (before the DWARF sections 421 // emitted by AsmPrinter::doInitialization) so the assembler will keep 422 // them together at the beginning of the object file. This helps 423 // avoid out-of-range branches that are due a fundamental limitation of 424 // the way symbol offsets are encoded with the current Darwin ARM 425 // relocations. 426 const TargetLoweringObjectFileMachO &TLOFMacho = 427 static_cast<const TargetLoweringObjectFileMachO &>( 428 getObjFileLowering()); 429 430 // Collect the set of sections our functions will go into. 431 SetVector<const MCSection *, SmallVector<const MCSection *, 8>, 432 SmallPtrSet<const MCSection *, 8> > TextSections; 433 // Default text section comes first. 434 TextSections.insert(TLOFMacho.getTextSection()); 435 // Now any user defined text sections from function attributes. 436 for (Module::iterator F = M.begin(), e = M.end(); F != e; ++F) 437 if (!F->isDeclaration() && !F->hasAvailableExternallyLinkage()) 438 TextSections.insert(TLOFMacho.SectionForGlobal(F, *Mang, TM)); 439 // Now the coalescable sections. 440 TextSections.insert(TLOFMacho.getTextCoalSection()); 441 TextSections.insert(TLOFMacho.getConstTextCoalSection()); 442 443 // Emit the sections in the .s file header to fix the order. 444 for (unsigned i = 0, e = TextSections.size(); i != e; ++i) 445 OutStreamer.SwitchSection(TextSections[i]); 446 447 if (RelocM == Reloc::DynamicNoPIC) { 448 const MCSection *sect = 449 OutContext.getMachOSection("__TEXT", "__symbol_stub4", 450 MachO::S_SYMBOL_STUBS, 451 12, SectionKind::getText()); 452 OutStreamer.SwitchSection(sect); 453 } else { 454 const MCSection *sect = 455 OutContext.getMachOSection("__TEXT", "__picsymbolstub4", 456 MachO::S_SYMBOL_STUBS, 457 16, SectionKind::getText()); 458 OutStreamer.SwitchSection(sect); 459 } 460 const MCSection *StaticInitSect = 461 OutContext.getMachOSection("__TEXT", "__StaticInit", 462 MachO::S_REGULAR | 463 MachO::S_ATTR_PURE_INSTRUCTIONS, 464 SectionKind::getText()); 465 OutStreamer.SwitchSection(StaticInitSect); 466 } 467 468 // Compiling with debug info should not affect the code 469 // generation. Ensure the cstring section comes before the 470 // optional __DWARF secion. Otherwise, PC-relative loads would 471 // have to use different instruction sequences at "-g" in order to 472 // reach global data in the same object file. 473 OutStreamer.SwitchSection(getObjFileLowering().getCStringSection()); 474 } 475 476 // Use unified assembler syntax. 477 OutStreamer.EmitAssemblerFlag(MCAF_SyntaxUnified); 478 479 // Emit ARM Build Attributes 480 if (Subtarget->isTargetELF()) 481 emitAttributes(); 482 483 if (!M.getModuleInlineAsm().empty() && Subtarget->isThumb()) 484 OutStreamer.EmitAssemblerFlag(MCAF_Code16); 485 } 486 487 static void 488 emitNonLazySymbolPointer(MCStreamer &OutStreamer, MCSymbol *StubLabel, 489 MachineModuleInfoImpl::StubValueTy &MCSym) { 490 // L_foo$stub: 491 OutStreamer.EmitLabel(StubLabel); 492 // .indirect_symbol _foo 493 OutStreamer.EmitSymbolAttribute(MCSym.getPointer(), MCSA_IndirectSymbol); 494 495 if (MCSym.getInt()) 496 // External to current translation unit. 497 OutStreamer.EmitIntValue(0, 4/*size*/); 498 else 499 // Internal to current translation unit. 500 // 501 // When we place the LSDA into the TEXT section, the type info 502 // pointers need to be indirect and pc-rel. We accomplish this by 503 // using NLPs; however, sometimes the types are local to the file. 504 // We need to fill in the value for the NLP in those cases. 505 OutStreamer.EmitValue( 506 MCSymbolRefExpr::Create(MCSym.getPointer(), OutStreamer.getContext()), 507 4 /*size*/); 508 } 509 510 511 void ARMAsmPrinter::EmitEndOfAsmFile(Module &M) { 512 if (Subtarget->isTargetMachO()) { 513 // All darwin targets use mach-o. 514 const TargetLoweringObjectFileMachO &TLOFMacho = 515 static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering()); 516 MachineModuleInfoMachO &MMIMacho = 517 MMI->getObjFileInfo<MachineModuleInfoMachO>(); 518 519 // Output non-lazy-pointers for external and common global variables. 520 MachineModuleInfoMachO::SymbolListTy Stubs = MMIMacho.GetGVStubList(); 521 522 if (!Stubs.empty()) { 523 // Switch with ".non_lazy_symbol_pointer" directive. 524 OutStreamer.SwitchSection(TLOFMacho.getNonLazySymbolPointerSection()); 525 EmitAlignment(2); 526 527 for (auto &Stub : Stubs) 528 emitNonLazySymbolPointer(OutStreamer, Stub.first, Stub.second); 529 530 Stubs.clear(); 531 OutStreamer.AddBlankLine(); 532 } 533 534 Stubs = MMIMacho.GetHiddenGVStubList(); 535 if (!Stubs.empty()) { 536 OutStreamer.SwitchSection(TLOFMacho.getNonLazySymbolPointerSection()); 537 EmitAlignment(2); 538 539 for (auto &Stub : Stubs) 540 emitNonLazySymbolPointer(OutStreamer, Stub.first, Stub.second); 541 542 Stubs.clear(); 543 OutStreamer.AddBlankLine(); 544 } 545 546 // Funny Darwin hack: This flag tells the linker that no global symbols 547 // contain code that falls through to other global symbols (e.g. the obvious 548 // implementation of multiple entry points). If this doesn't occur, the 549 // linker can safely perform dead code stripping. Since LLVM never 550 // generates code that does this, it is always safe to set. 551 OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols); 552 } 553 554 // Emit a .data.rel section containing any stubs that were created. 555 if (Subtarget->isTargetELF()) { 556 const TargetLoweringObjectFileELF &TLOFELF = 557 static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering()); 558 559 MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>(); 560 561 // Output stubs for external and common global variables. 562 MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList(); 563 if (!Stubs.empty()) { 564 OutStreamer.SwitchSection(TLOFELF.getDataRelSection()); 565 const DataLayout *TD = TM.getSubtargetImpl()->getDataLayout(); 566 567 for (auto &stub: Stubs) { 568 OutStreamer.EmitLabel(stub.first); 569 OutStreamer.EmitSymbolValue(stub.second.getPointer(), 570 TD->getPointerSize(0)); 571 } 572 Stubs.clear(); 573 } 574 } 575 } 576 577 //===----------------------------------------------------------------------===// 578 // Helper routines for EmitStartOfAsmFile() and EmitEndOfAsmFile() 579 // FIXME: 580 // The following seem like one-off assembler flags, but they actually need 581 // to appear in the .ARM.attributes section in ELF. 582 // Instead of subclassing the MCELFStreamer, we do the work here. 583 584 static ARMBuildAttrs::CPUArch getArchForCPU(StringRef CPU, 585 const ARMSubtarget *Subtarget) { 586 if (CPU == "xscale") 587 return ARMBuildAttrs::v5TEJ; 588 589 if (Subtarget->hasV8Ops()) 590 return ARMBuildAttrs::v8; 591 else if (Subtarget->hasV7Ops()) { 592 if (Subtarget->isMClass() && Subtarget->hasThumb2DSP()) 593 return ARMBuildAttrs::v7E_M; 594 return ARMBuildAttrs::v7; 595 } else if (Subtarget->hasV6T2Ops()) 596 return ARMBuildAttrs::v6T2; 597 else if (Subtarget->hasV6MOps()) 598 return ARMBuildAttrs::v6S_M; 599 else if (Subtarget->hasV6Ops()) 600 return ARMBuildAttrs::v6; 601 else if (Subtarget->hasV5TEOps()) 602 return ARMBuildAttrs::v5TE; 603 else if (Subtarget->hasV5TOps()) 604 return ARMBuildAttrs::v5T; 605 else if (Subtarget->hasV4TOps()) 606 return ARMBuildAttrs::v4T; 607 else 608 return ARMBuildAttrs::v4; 609 } 610 611 void ARMAsmPrinter::emitAttributes() { 612 MCTargetStreamer &TS = *OutStreamer.getTargetStreamer(); 613 ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS); 614 615 ATS.switchVendor("aeabi"); 616 617 std::string CPUString = Subtarget->getCPUString(); 618 619 // FIXME: remove krait check when GNU tools support krait cpu 620 if (CPUString != "generic" && CPUString != "krait") 621 ATS.emitTextAttribute(ARMBuildAttrs::CPU_name, CPUString); 622 623 ATS.emitAttribute(ARMBuildAttrs::CPU_arch, 624 getArchForCPU(CPUString, Subtarget)); 625 626 // Tag_CPU_arch_profile must have the default value of 0 when "Architecture 627 // profile is not applicable (e.g. pre v7, or cross-profile code)". 628 if (Subtarget->hasV7Ops()) { 629 if (Subtarget->isAClass()) { 630 ATS.emitAttribute(ARMBuildAttrs::CPU_arch_profile, 631 ARMBuildAttrs::ApplicationProfile); 632 } else if (Subtarget->isRClass()) { 633 ATS.emitAttribute(ARMBuildAttrs::CPU_arch_profile, 634 ARMBuildAttrs::RealTimeProfile); 635 } else if (Subtarget->isMClass()) { 636 ATS.emitAttribute(ARMBuildAttrs::CPU_arch_profile, 637 ARMBuildAttrs::MicroControllerProfile); 638 } 639 } 640 641 ATS.emitAttribute(ARMBuildAttrs::ARM_ISA_use, Subtarget->hasARMOps() ? 642 ARMBuildAttrs::Allowed : ARMBuildAttrs::Not_Allowed); 643 if (Subtarget->isThumb1Only()) { 644 ATS.emitAttribute(ARMBuildAttrs::THUMB_ISA_use, 645 ARMBuildAttrs::Allowed); 646 } else if (Subtarget->hasThumb2()) { 647 ATS.emitAttribute(ARMBuildAttrs::THUMB_ISA_use, 648 ARMBuildAttrs::AllowThumb32); 649 } 650 651 if (Subtarget->hasNEON()) { 652 /* NEON is not exactly a VFP architecture, but GAS emit one of 653 * neon/neon-fp-armv8/neon-vfpv4/vfpv3/vfpv2 for .fpu parameters */ 654 if (Subtarget->hasFPARMv8()) { 655 if (Subtarget->hasCrypto()) 656 ATS.emitFPU(ARM::CRYPTO_NEON_FP_ARMV8); 657 else 658 ATS.emitFPU(ARM::NEON_FP_ARMV8); 659 } 660 else if (Subtarget->hasVFP4()) 661 ATS.emitFPU(ARM::NEON_VFPV4); 662 else 663 ATS.emitFPU(ARM::NEON); 664 // Emit Tag_Advanced_SIMD_arch for ARMv8 architecture 665 if (Subtarget->hasV8Ops()) 666 ATS.emitAttribute(ARMBuildAttrs::Advanced_SIMD_arch, 667 ARMBuildAttrs::AllowNeonARMv8); 668 } else { 669 if (Subtarget->hasFPARMv8()) 670 ATS.emitFPU(ARM::FP_ARMV8); 671 else if (Subtarget->hasVFP4()) 672 ATS.emitFPU(Subtarget->hasD16() ? ARM::VFPV4_D16 : ARM::VFPV4); 673 else if (Subtarget->hasVFP3()) 674 ATS.emitFPU(Subtarget->hasD16() ? ARM::VFPV3_D16 : ARM::VFPV3); 675 else if (Subtarget->hasVFP2()) 676 ATS.emitFPU(ARM::VFPV2); 677 } 678 679 if (TM.getRelocationModel() == Reloc::PIC_) { 680 // PIC specific attributes. 681 ATS.emitAttribute(ARMBuildAttrs::ABI_PCS_RW_data, 682 ARMBuildAttrs::AddressRWPCRel); 683 ATS.emitAttribute(ARMBuildAttrs::ABI_PCS_RO_data, 684 ARMBuildAttrs::AddressROPCRel); 685 ATS.emitAttribute(ARMBuildAttrs::ABI_PCS_GOT_use, 686 ARMBuildAttrs::AddressGOT); 687 } else { 688 // Allow direct addressing of imported data for all other relocation models. 689 ATS.emitAttribute(ARMBuildAttrs::ABI_PCS_GOT_use, 690 ARMBuildAttrs::AddressDirect); 691 } 692 693 // Signal various FP modes. 694 if (!TM.Options.UnsafeFPMath) { 695 ATS.emitAttribute(ARMBuildAttrs::ABI_FP_denormal, ARMBuildAttrs::Allowed); 696 ATS.emitAttribute(ARMBuildAttrs::ABI_FP_exceptions, 697 ARMBuildAttrs::Allowed); 698 } 699 700 if (TM.Options.NoInfsFPMath && TM.Options.NoNaNsFPMath) 701 ATS.emitAttribute(ARMBuildAttrs::ABI_FP_number_model, 702 ARMBuildAttrs::Allowed); 703 else 704 ATS.emitAttribute(ARMBuildAttrs::ABI_FP_number_model, 705 ARMBuildAttrs::AllowIEE754); 706 707 // FIXME: add more flags to ARMBuildAttributes.h 708 // 8-bytes alignment stuff. 709 ATS.emitAttribute(ARMBuildAttrs::ABI_align_needed, 1); 710 ATS.emitAttribute(ARMBuildAttrs::ABI_align_preserved, 1); 711 712 // ABI_HardFP_use attribute to indicate single precision FP. 713 if (Subtarget->isFPOnlySP()) 714 ATS.emitAttribute(ARMBuildAttrs::ABI_HardFP_use, 715 ARMBuildAttrs::HardFPSinglePrecision); 716 717 // Hard float. Use both S and D registers and conform to AAPCS-VFP. 718 if (Subtarget->isAAPCS_ABI() && TM.Options.FloatABIType == FloatABI::Hard) 719 ATS.emitAttribute(ARMBuildAttrs::ABI_VFP_args, ARMBuildAttrs::HardFPAAPCS); 720 721 // FIXME: Should we signal R9 usage? 722 723 if (Subtarget->hasFP16()) 724 ATS.emitAttribute(ARMBuildAttrs::FP_HP_extension, ARMBuildAttrs::AllowHPFP); 725 726 if (Subtarget->hasMPExtension()) 727 ATS.emitAttribute(ARMBuildAttrs::MPextension_use, ARMBuildAttrs::AllowMP); 728 729 // Hardware divide in ARM mode is part of base arch, starting from ARMv8. 730 // If only Thumb hwdiv is present, it must also be in base arch (ARMv7-R/M). 731 // It is not possible to produce DisallowDIV: if hwdiv is present in the base 732 // arch, supplying -hwdiv downgrades the effective arch, via ClearImpliedBits. 733 // AllowDIVExt is only emitted if hwdiv isn't available in the base arch; 734 // otherwise, the default value (AllowDIVIfExists) applies. 735 if (Subtarget->hasDivideInARMMode() && !Subtarget->hasV8Ops()) 736 ATS.emitAttribute(ARMBuildAttrs::DIV_use, ARMBuildAttrs::AllowDIVExt); 737 738 if (MMI) { 739 if (const Module *SourceModule = MMI->getModule()) { 740 // ABI_PCS_wchar_t to indicate wchar_t width 741 // FIXME: There is no way to emit value 0 (wchar_t prohibited). 742 if (auto WCharWidthValue = cast_or_null<ConstantInt>( 743 SourceModule->getModuleFlag("wchar_size"))) { 744 int WCharWidth = WCharWidthValue->getZExtValue(); 745 assert((WCharWidth == 2 || WCharWidth == 4) && 746 "wchar_t width must be 2 or 4 bytes"); 747 ATS.emitAttribute(ARMBuildAttrs::ABI_PCS_wchar_t, WCharWidth); 748 } 749 750 // ABI_enum_size to indicate enum width 751 // FIXME: There is no way to emit value 0 (enums prohibited) or value 3 752 // (all enums contain a value needing 32 bits to encode). 753 if (auto EnumWidthValue = cast_or_null<ConstantInt>( 754 SourceModule->getModuleFlag("min_enum_size"))) { 755 int EnumWidth = EnumWidthValue->getZExtValue(); 756 assert((EnumWidth == 1 || EnumWidth == 4) && 757 "Minimum enum width must be 1 or 4 bytes"); 758 int EnumBuildAttr = EnumWidth == 1 ? 1 : 2; 759 ATS.emitAttribute(ARMBuildAttrs::ABI_enum_size, EnumBuildAttr); 760 } 761 } 762 } 763 764 // TODO: We currently only support either reserving the register, or treating 765 // it as another callee-saved register, but not as SB or a TLS pointer; It 766 // would instead be nicer to push this from the frontend as metadata, as we do 767 // for the wchar and enum size tags 768 if (Subtarget->isR9Reserved()) 769 ATS.emitAttribute(ARMBuildAttrs::ABI_PCS_R9_use, 770 ARMBuildAttrs::R9Reserved); 771 else 772 ATS.emitAttribute(ARMBuildAttrs::ABI_PCS_R9_use, 773 ARMBuildAttrs::R9IsGPR); 774 775 if (Subtarget->hasTrustZone() && Subtarget->hasVirtualization()) 776 ATS.emitAttribute(ARMBuildAttrs::Virtualization_use, 777 ARMBuildAttrs::AllowTZVirtualization); 778 else if (Subtarget->hasTrustZone()) 779 ATS.emitAttribute(ARMBuildAttrs::Virtualization_use, 780 ARMBuildAttrs::AllowTZ); 781 else if (Subtarget->hasVirtualization()) 782 ATS.emitAttribute(ARMBuildAttrs::Virtualization_use, 783 ARMBuildAttrs::AllowVirtualization); 784 785 ATS.finishAttributeSection(); 786 } 787 788 //===----------------------------------------------------------------------===// 789 790 static MCSymbol *getPICLabel(const char *Prefix, unsigned FunctionNumber, 791 unsigned LabelId, MCContext &Ctx) { 792 793 MCSymbol *Label = Ctx.GetOrCreateSymbol(Twine(Prefix) 794 + "PC" + Twine(FunctionNumber) + "_" + Twine(LabelId)); 795 return Label; 796 } 797 798 static MCSymbolRefExpr::VariantKind 799 getModifierVariantKind(ARMCP::ARMCPModifier Modifier) { 800 switch (Modifier) { 801 case ARMCP::no_modifier: return MCSymbolRefExpr::VK_None; 802 case ARMCP::TLSGD: return MCSymbolRefExpr::VK_TLSGD; 803 case ARMCP::TPOFF: return MCSymbolRefExpr::VK_TPOFF; 804 case ARMCP::GOTTPOFF: return MCSymbolRefExpr::VK_GOTTPOFF; 805 case ARMCP::GOT: return MCSymbolRefExpr::VK_GOT; 806 case ARMCP::GOTOFF: return MCSymbolRefExpr::VK_GOTOFF; 807 } 808 llvm_unreachable("Invalid ARMCPModifier!"); 809 } 810 811 MCSymbol *ARMAsmPrinter::GetARMGVSymbol(const GlobalValue *GV, 812 unsigned char TargetFlags) { 813 if (Subtarget->isTargetMachO()) { 814 bool IsIndirect = (TargetFlags & ARMII::MO_NONLAZY) && 815 Subtarget->GVIsIndirectSymbol(GV, TM.getRelocationModel()); 816 817 if (!IsIndirect) 818 return getSymbol(GV); 819 820 // FIXME: Remove this when Darwin transition to @GOT like syntax. 821 MCSymbol *MCSym = getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr"); 822 MachineModuleInfoMachO &MMIMachO = 823 MMI->getObjFileInfo<MachineModuleInfoMachO>(); 824 MachineModuleInfoImpl::StubValueTy &StubSym = 825 GV->hasHiddenVisibility() ? MMIMachO.getHiddenGVStubEntry(MCSym) 826 : MMIMachO.getGVStubEntry(MCSym); 827 if (!StubSym.getPointer()) 828 StubSym = MachineModuleInfoImpl::StubValueTy(getSymbol(GV), 829 !GV->hasInternalLinkage()); 830 return MCSym; 831 } else if (Subtarget->isTargetCOFF()) { 832 assert(Subtarget->isTargetWindows() && 833 "Windows is the only supported COFF target"); 834 835 bool IsIndirect = (TargetFlags & ARMII::MO_DLLIMPORT); 836 if (!IsIndirect) 837 return getSymbol(GV); 838 839 SmallString<128> Name; 840 Name = "__imp_"; 841 getNameWithPrefix(Name, GV); 842 843 return OutContext.GetOrCreateSymbol(Name); 844 } else if (Subtarget->isTargetELF()) { 845 return getSymbol(GV); 846 } 847 llvm_unreachable("unexpected target"); 848 } 849 850 void ARMAsmPrinter:: 851 EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) { 852 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout(); 853 int Size = 854 TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(MCPV->getType()); 855 856 ARMConstantPoolValue *ACPV = static_cast<ARMConstantPoolValue*>(MCPV); 857 858 MCSymbol *MCSym; 859 if (ACPV->isLSDA()) { 860 SmallString<128> Str; 861 raw_svector_ostream OS(Str); 862 OS << DL->getPrivateGlobalPrefix() << "_LSDA_" << getFunctionNumber(); 863 MCSym = OutContext.GetOrCreateSymbol(OS.str()); 864 } else if (ACPV->isBlockAddress()) { 865 const BlockAddress *BA = 866 cast<ARMConstantPoolConstant>(ACPV)->getBlockAddress(); 867 MCSym = GetBlockAddressSymbol(BA); 868 } else if (ACPV->isGlobalValue()) { 869 const GlobalValue *GV = cast<ARMConstantPoolConstant>(ACPV)->getGV(); 870 871 // On Darwin, const-pool entries may get the "FOO$non_lazy_ptr" mangling, so 872 // flag the global as MO_NONLAZY. 873 unsigned char TF = Subtarget->isTargetMachO() ? ARMII::MO_NONLAZY : 0; 874 MCSym = GetARMGVSymbol(GV, TF); 875 } else if (ACPV->isMachineBasicBlock()) { 876 const MachineBasicBlock *MBB = cast<ARMConstantPoolMBB>(ACPV)->getMBB(); 877 MCSym = MBB->getSymbol(); 878 } else { 879 assert(ACPV->isExtSymbol() && "unrecognized constant pool value"); 880 const char *Sym = cast<ARMConstantPoolSymbol>(ACPV)->getSymbol(); 881 MCSym = GetExternalSymbolSymbol(Sym); 882 } 883 884 // Create an MCSymbol for the reference. 885 const MCExpr *Expr = 886 MCSymbolRefExpr::Create(MCSym, getModifierVariantKind(ACPV->getModifier()), 887 OutContext); 888 889 if (ACPV->getPCAdjustment()) { 890 MCSymbol *PCLabel = getPICLabel(DL->getPrivateGlobalPrefix(), 891 getFunctionNumber(), 892 ACPV->getLabelId(), 893 OutContext); 894 const MCExpr *PCRelExpr = MCSymbolRefExpr::Create(PCLabel, OutContext); 895 PCRelExpr = 896 MCBinaryExpr::CreateAdd(PCRelExpr, 897 MCConstantExpr::Create(ACPV->getPCAdjustment(), 898 OutContext), 899 OutContext); 900 if (ACPV->mustAddCurrentAddress()) { 901 // We want "(<expr> - .)", but MC doesn't have a concept of the '.' 902 // label, so just emit a local label end reference that instead. 903 MCSymbol *DotSym = OutContext.CreateTempSymbol(); 904 OutStreamer.EmitLabel(DotSym); 905 const MCExpr *DotExpr = MCSymbolRefExpr::Create(DotSym, OutContext); 906 PCRelExpr = MCBinaryExpr::CreateSub(PCRelExpr, DotExpr, OutContext); 907 } 908 Expr = MCBinaryExpr::CreateSub(Expr, PCRelExpr, OutContext); 909 } 910 OutStreamer.EmitValue(Expr, Size); 911 } 912 913 void ARMAsmPrinter::EmitJumpTable(const MachineInstr *MI) { 914 unsigned Opcode = MI->getOpcode(); 915 int OpNum = 1; 916 if (Opcode == ARM::BR_JTadd) 917 OpNum = 2; 918 else if (Opcode == ARM::BR_JTm) 919 OpNum = 3; 920 921 const MachineOperand &MO1 = MI->getOperand(OpNum); 922 const MachineOperand &MO2 = MI->getOperand(OpNum+1); // Unique Id 923 unsigned JTI = MO1.getIndex(); 924 925 // Emit a label for the jump table. 926 MCSymbol *JTISymbol = GetARMJTIPICJumpTableLabel2(JTI, MO2.getImm()); 927 OutStreamer.EmitLabel(JTISymbol); 928 929 // Mark the jump table as data-in-code. 930 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32); 931 932 // Emit each entry of the table. 933 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 934 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 935 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 936 937 for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) { 938 MachineBasicBlock *MBB = JTBBs[i]; 939 // Construct an MCExpr for the entry. We want a value of the form: 940 // (BasicBlockAddr - TableBeginAddr) 941 // 942 // For example, a table with entries jumping to basic blocks BB0 and BB1 943 // would look like: 944 // LJTI_0_0: 945 // .word (LBB0 - LJTI_0_0) 946 // .word (LBB1 - LJTI_0_0) 947 const MCExpr *Expr = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 948 949 if (TM.getRelocationModel() == Reloc::PIC_) 950 Expr = MCBinaryExpr::CreateSub(Expr, MCSymbolRefExpr::Create(JTISymbol, 951 OutContext), 952 OutContext); 953 // If we're generating a table of Thumb addresses in static relocation 954 // model, we need to add one to keep interworking correctly. 955 else if (AFI->isThumbFunction()) 956 Expr = MCBinaryExpr::CreateAdd(Expr, MCConstantExpr::Create(1,OutContext), 957 OutContext); 958 OutStreamer.EmitValue(Expr, 4); 959 } 960 // Mark the end of jump table data-in-code region. 961 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd); 962 } 963 964 void ARMAsmPrinter::EmitJump2Table(const MachineInstr *MI) { 965 unsigned Opcode = MI->getOpcode(); 966 int OpNum = (Opcode == ARM::t2BR_JT) ? 2 : 1; 967 const MachineOperand &MO1 = MI->getOperand(OpNum); 968 const MachineOperand &MO2 = MI->getOperand(OpNum+1); // Unique Id 969 unsigned JTI = MO1.getIndex(); 970 971 MCSymbol *JTISymbol = GetARMJTIPICJumpTableLabel2(JTI, MO2.getImm()); 972 OutStreamer.EmitLabel(JTISymbol); 973 974 // Emit each entry of the table. 975 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 976 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 977 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 978 unsigned OffsetWidth = 4; 979 if (MI->getOpcode() == ARM::t2TBB_JT) { 980 OffsetWidth = 1; 981 // Mark the jump table as data-in-code. 982 OutStreamer.EmitDataRegion(MCDR_DataRegionJT8); 983 } else if (MI->getOpcode() == ARM::t2TBH_JT) { 984 OffsetWidth = 2; 985 // Mark the jump table as data-in-code. 986 OutStreamer.EmitDataRegion(MCDR_DataRegionJT16); 987 } 988 989 for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) { 990 MachineBasicBlock *MBB = JTBBs[i]; 991 const MCExpr *MBBSymbolExpr = MCSymbolRefExpr::Create(MBB->getSymbol(), 992 OutContext); 993 // If this isn't a TBB or TBH, the entries are direct branch instructions. 994 if (OffsetWidth == 4) { 995 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::t2B) 996 .addExpr(MBBSymbolExpr) 997 .addImm(ARMCC::AL) 998 .addReg(0)); 999 continue; 1000 } 1001 // Otherwise it's an offset from the dispatch instruction. Construct an 1002 // MCExpr for the entry. We want a value of the form: 1003 // (BasicBlockAddr - TableBeginAddr) / 2 1004 // 1005 // For example, a TBB table with entries jumping to basic blocks BB0 and BB1 1006 // would look like: 1007 // LJTI_0_0: 1008 // .byte (LBB0 - LJTI_0_0) / 2 1009 // .byte (LBB1 - LJTI_0_0) / 2 1010 const MCExpr *Expr = 1011 MCBinaryExpr::CreateSub(MBBSymbolExpr, 1012 MCSymbolRefExpr::Create(JTISymbol, OutContext), 1013 OutContext); 1014 Expr = MCBinaryExpr::CreateDiv(Expr, MCConstantExpr::Create(2, OutContext), 1015 OutContext); 1016 OutStreamer.EmitValue(Expr, OffsetWidth); 1017 } 1018 // Mark the end of jump table data-in-code region. 32-bit offsets use 1019 // actual branch instructions here, so we don't mark those as a data-region 1020 // at all. 1021 if (OffsetWidth != 4) 1022 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd); 1023 } 1024 1025 void ARMAsmPrinter::EmitUnwindingInstruction(const MachineInstr *MI) { 1026 assert(MI->getFlag(MachineInstr::FrameSetup) && 1027 "Only instruction which are involved into frame setup code are allowed"); 1028 1029 MCTargetStreamer &TS = *OutStreamer.getTargetStreamer(); 1030 ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS); 1031 const MachineFunction &MF = *MI->getParent()->getParent(); 1032 const TargetRegisterInfo *RegInfo = MF.getSubtarget().getRegisterInfo(); 1033 const ARMFunctionInfo &AFI = *MF.getInfo<ARMFunctionInfo>(); 1034 1035 unsigned FramePtr = RegInfo->getFrameRegister(MF); 1036 unsigned Opc = MI->getOpcode(); 1037 unsigned SrcReg, DstReg; 1038 1039 if (Opc == ARM::tPUSH || Opc == ARM::tLDRpci) { 1040 // Two special cases: 1041 // 1) tPUSH does not have src/dst regs. 1042 // 2) for Thumb1 code we sometimes materialize the constant via constpool 1043 // load. Yes, this is pretty fragile, but for now I don't see better 1044 // way... :( 1045 SrcReg = DstReg = ARM::SP; 1046 } else { 1047 SrcReg = MI->getOperand(1).getReg(); 1048 DstReg = MI->getOperand(0).getReg(); 1049 } 1050 1051 // Try to figure out the unwinding opcode out of src / dst regs. 1052 if (MI->mayStore()) { 1053 // Register saves. 1054 assert(DstReg == ARM::SP && 1055 "Only stack pointer as a destination reg is supported"); 1056 1057 SmallVector<unsigned, 4> RegList; 1058 // Skip src & dst reg, and pred ops. 1059 unsigned StartOp = 2 + 2; 1060 // Use all the operands. 1061 unsigned NumOffset = 0; 1062 1063 switch (Opc) { 1064 default: 1065 MI->dump(); 1066 llvm_unreachable("Unsupported opcode for unwinding information"); 1067 case ARM::tPUSH: 1068 // Special case here: no src & dst reg, but two extra imp ops. 1069 StartOp = 2; NumOffset = 2; 1070 case ARM::STMDB_UPD: 1071 case ARM::t2STMDB_UPD: 1072 case ARM::VSTMDDB_UPD: 1073 assert(SrcReg == ARM::SP && 1074 "Only stack pointer as a source reg is supported"); 1075 for (unsigned i = StartOp, NumOps = MI->getNumOperands() - NumOffset; 1076 i != NumOps; ++i) { 1077 const MachineOperand &MO = MI->getOperand(i); 1078 // Actually, there should never be any impdef stuff here. Skip it 1079 // temporary to workaround PR11902. 1080 if (MO.isImplicit()) 1081 continue; 1082 RegList.push_back(MO.getReg()); 1083 } 1084 break; 1085 case ARM::STR_PRE_IMM: 1086 case ARM::STR_PRE_REG: 1087 case ARM::t2STR_PRE: 1088 assert(MI->getOperand(2).getReg() == ARM::SP && 1089 "Only stack pointer as a source reg is supported"); 1090 RegList.push_back(SrcReg); 1091 break; 1092 } 1093 if (MAI->getExceptionHandlingType() == ExceptionHandling::ARM) 1094 ATS.emitRegSave(RegList, Opc == ARM::VSTMDDB_UPD); 1095 } else { 1096 // Changes of stack / frame pointer. 1097 if (SrcReg == ARM::SP) { 1098 int64_t Offset = 0; 1099 switch (Opc) { 1100 default: 1101 MI->dump(); 1102 llvm_unreachable("Unsupported opcode for unwinding information"); 1103 case ARM::MOVr: 1104 case ARM::tMOVr: 1105 Offset = 0; 1106 break; 1107 case ARM::ADDri: 1108 Offset = -MI->getOperand(2).getImm(); 1109 break; 1110 case ARM::SUBri: 1111 case ARM::t2SUBri: 1112 Offset = MI->getOperand(2).getImm(); 1113 break; 1114 case ARM::tSUBspi: 1115 Offset = MI->getOperand(2).getImm()*4; 1116 break; 1117 case ARM::tADDspi: 1118 case ARM::tADDrSPi: 1119 Offset = -MI->getOperand(2).getImm()*4; 1120 break; 1121 case ARM::tLDRpci: { 1122 // Grab the constpool index and check, whether it corresponds to 1123 // original or cloned constpool entry. 1124 unsigned CPI = MI->getOperand(1).getIndex(); 1125 const MachineConstantPool *MCP = MF.getConstantPool(); 1126 if (CPI >= MCP->getConstants().size()) 1127 CPI = AFI.getOriginalCPIdx(CPI); 1128 assert(CPI != -1U && "Invalid constpool index"); 1129 1130 // Derive the actual offset. 1131 const MachineConstantPoolEntry &CPE = MCP->getConstants()[CPI]; 1132 assert(!CPE.isMachineConstantPoolEntry() && "Invalid constpool entry"); 1133 // FIXME: Check for user, it should be "add" instruction! 1134 Offset = -cast<ConstantInt>(CPE.Val.ConstVal)->getSExtValue(); 1135 break; 1136 } 1137 } 1138 1139 if (MAI->getExceptionHandlingType() == ExceptionHandling::ARM) { 1140 if (DstReg == FramePtr && FramePtr != ARM::SP) 1141 // Set-up of the frame pointer. Positive values correspond to "add" 1142 // instruction. 1143 ATS.emitSetFP(FramePtr, ARM::SP, -Offset); 1144 else if (DstReg == ARM::SP) { 1145 // Change of SP by an offset. Positive values correspond to "sub" 1146 // instruction. 1147 ATS.emitPad(Offset); 1148 } else { 1149 // Move of SP to a register. Positive values correspond to an "add" 1150 // instruction. 1151 ATS.emitMovSP(DstReg, -Offset); 1152 } 1153 } 1154 } else if (DstReg == ARM::SP) { 1155 MI->dump(); 1156 llvm_unreachable("Unsupported opcode for unwinding information"); 1157 } 1158 else { 1159 MI->dump(); 1160 llvm_unreachable("Unsupported opcode for unwinding information"); 1161 } 1162 } 1163 } 1164 1165 // Simple pseudo-instructions have their lowering (with expansion to real 1166 // instructions) auto-generated. 1167 #include "ARMGenMCPseudoLowering.inc" 1168 1169 void ARMAsmPrinter::EmitInstruction(const MachineInstr *MI) { 1170 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout(); 1171 1172 // If we just ended a constant pool, mark it as such. 1173 if (InConstantPool && MI->getOpcode() != ARM::CONSTPOOL_ENTRY) { 1174 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd); 1175 InConstantPool = false; 1176 } 1177 1178 // Emit unwinding stuff for frame-related instructions 1179 if (Subtarget->isTargetEHABICompatible() && 1180 MI->getFlag(MachineInstr::FrameSetup)) 1181 EmitUnwindingInstruction(MI); 1182 1183 // Do any auto-generated pseudo lowerings. 1184 if (emitPseudoExpansionLowering(OutStreamer, MI)) 1185 return; 1186 1187 assert(!convertAddSubFlagsOpcode(MI->getOpcode()) && 1188 "Pseudo flag setting opcode should be expanded early"); 1189 1190 // Check for manual lowerings. 1191 unsigned Opc = MI->getOpcode(); 1192 switch (Opc) { 1193 case ARM::t2MOVi32imm: llvm_unreachable("Should be lowered by thumb2it pass"); 1194 case ARM::DBG_VALUE: llvm_unreachable("Should be handled by generic printing"); 1195 case ARM::LEApcrel: 1196 case ARM::tLEApcrel: 1197 case ARM::t2LEApcrel: { 1198 // FIXME: Need to also handle globals and externals 1199 MCSymbol *CPISymbol = GetCPISymbol(MI->getOperand(1).getIndex()); 1200 EmitToStreamer(OutStreamer, MCInstBuilder(MI->getOpcode() == 1201 ARM::t2LEApcrel ? ARM::t2ADR 1202 : (MI->getOpcode() == ARM::tLEApcrel ? ARM::tADR 1203 : ARM::ADR)) 1204 .addReg(MI->getOperand(0).getReg()) 1205 .addExpr(MCSymbolRefExpr::Create(CPISymbol, OutContext)) 1206 // Add predicate operands. 1207 .addImm(MI->getOperand(2).getImm()) 1208 .addReg(MI->getOperand(3).getReg())); 1209 return; 1210 } 1211 case ARM::LEApcrelJT: 1212 case ARM::tLEApcrelJT: 1213 case ARM::t2LEApcrelJT: { 1214 MCSymbol *JTIPICSymbol = 1215 GetARMJTIPICJumpTableLabel2(MI->getOperand(1).getIndex(), 1216 MI->getOperand(2).getImm()); 1217 EmitToStreamer(OutStreamer, MCInstBuilder(MI->getOpcode() == 1218 ARM::t2LEApcrelJT ? ARM::t2ADR 1219 : (MI->getOpcode() == ARM::tLEApcrelJT ? ARM::tADR 1220 : ARM::ADR)) 1221 .addReg(MI->getOperand(0).getReg()) 1222 .addExpr(MCSymbolRefExpr::Create(JTIPICSymbol, OutContext)) 1223 // Add predicate operands. 1224 .addImm(MI->getOperand(3).getImm()) 1225 .addReg(MI->getOperand(4).getReg())); 1226 return; 1227 } 1228 // Darwin call instructions are just normal call instructions with different 1229 // clobber semantics (they clobber R9). 1230 case ARM::BX_CALL: { 1231 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::MOVr) 1232 .addReg(ARM::LR) 1233 .addReg(ARM::PC) 1234 // Add predicate operands. 1235 .addImm(ARMCC::AL) 1236 .addReg(0) 1237 // Add 's' bit operand (always reg0 for this) 1238 .addReg(0)); 1239 1240 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::BX) 1241 .addReg(MI->getOperand(0).getReg())); 1242 return; 1243 } 1244 case ARM::tBX_CALL: { 1245 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tMOVr) 1246 .addReg(ARM::LR) 1247 .addReg(ARM::PC) 1248 // Add predicate operands. 1249 .addImm(ARMCC::AL) 1250 .addReg(0)); 1251 1252 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tBX) 1253 .addReg(MI->getOperand(0).getReg()) 1254 // Add predicate operands. 1255 .addImm(ARMCC::AL) 1256 .addReg(0)); 1257 return; 1258 } 1259 case ARM::BMOVPCRX_CALL: { 1260 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::MOVr) 1261 .addReg(ARM::LR) 1262 .addReg(ARM::PC) 1263 // Add predicate operands. 1264 .addImm(ARMCC::AL) 1265 .addReg(0) 1266 // Add 's' bit operand (always reg0 for this) 1267 .addReg(0)); 1268 1269 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::MOVr) 1270 .addReg(ARM::PC) 1271 .addReg(MI->getOperand(0).getReg()) 1272 // Add predicate operands. 1273 .addImm(ARMCC::AL) 1274 .addReg(0) 1275 // Add 's' bit operand (always reg0 for this) 1276 .addReg(0)); 1277 return; 1278 } 1279 case ARM::BMOVPCB_CALL: { 1280 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::MOVr) 1281 .addReg(ARM::LR) 1282 .addReg(ARM::PC) 1283 // Add predicate operands. 1284 .addImm(ARMCC::AL) 1285 .addReg(0) 1286 // Add 's' bit operand (always reg0 for this) 1287 .addReg(0)); 1288 1289 const MachineOperand &Op = MI->getOperand(0); 1290 const GlobalValue *GV = Op.getGlobal(); 1291 const unsigned TF = Op.getTargetFlags(); 1292 MCSymbol *GVSym = GetARMGVSymbol(GV, TF); 1293 const MCExpr *GVSymExpr = MCSymbolRefExpr::Create(GVSym, OutContext); 1294 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::Bcc) 1295 .addExpr(GVSymExpr) 1296 // Add predicate operands. 1297 .addImm(ARMCC::AL) 1298 .addReg(0)); 1299 return; 1300 } 1301 case ARM::MOVi16_ga_pcrel: 1302 case ARM::t2MOVi16_ga_pcrel: { 1303 MCInst TmpInst; 1304 TmpInst.setOpcode(Opc == ARM::MOVi16_ga_pcrel? ARM::MOVi16 : ARM::t2MOVi16); 1305 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg())); 1306 1307 unsigned TF = MI->getOperand(1).getTargetFlags(); 1308 const GlobalValue *GV = MI->getOperand(1).getGlobal(); 1309 MCSymbol *GVSym = GetARMGVSymbol(GV, TF); 1310 const MCExpr *GVSymExpr = MCSymbolRefExpr::Create(GVSym, OutContext); 1311 1312 MCSymbol *LabelSym = getPICLabel(DL->getPrivateGlobalPrefix(), 1313 getFunctionNumber(), 1314 MI->getOperand(2).getImm(), OutContext); 1315 const MCExpr *LabelSymExpr= MCSymbolRefExpr::Create(LabelSym, OutContext); 1316 unsigned PCAdj = (Opc == ARM::MOVi16_ga_pcrel) ? 8 : 4; 1317 const MCExpr *PCRelExpr = 1318 ARMMCExpr::CreateLower16(MCBinaryExpr::CreateSub(GVSymExpr, 1319 MCBinaryExpr::CreateAdd(LabelSymExpr, 1320 MCConstantExpr::Create(PCAdj, OutContext), 1321 OutContext), OutContext), OutContext); 1322 TmpInst.addOperand(MCOperand::CreateExpr(PCRelExpr)); 1323 1324 // Add predicate operands. 1325 TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL)); 1326 TmpInst.addOperand(MCOperand::CreateReg(0)); 1327 // Add 's' bit operand (always reg0 for this) 1328 TmpInst.addOperand(MCOperand::CreateReg(0)); 1329 EmitToStreamer(OutStreamer, TmpInst); 1330 return; 1331 } 1332 case ARM::MOVTi16_ga_pcrel: 1333 case ARM::t2MOVTi16_ga_pcrel: { 1334 MCInst TmpInst; 1335 TmpInst.setOpcode(Opc == ARM::MOVTi16_ga_pcrel 1336 ? ARM::MOVTi16 : ARM::t2MOVTi16); 1337 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg())); 1338 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg())); 1339 1340 unsigned TF = MI->getOperand(2).getTargetFlags(); 1341 const GlobalValue *GV = MI->getOperand(2).getGlobal(); 1342 MCSymbol *GVSym = GetARMGVSymbol(GV, TF); 1343 const MCExpr *GVSymExpr = MCSymbolRefExpr::Create(GVSym, OutContext); 1344 1345 MCSymbol *LabelSym = getPICLabel(DL->getPrivateGlobalPrefix(), 1346 getFunctionNumber(), 1347 MI->getOperand(3).getImm(), OutContext); 1348 const MCExpr *LabelSymExpr= MCSymbolRefExpr::Create(LabelSym, OutContext); 1349 unsigned PCAdj = (Opc == ARM::MOVTi16_ga_pcrel) ? 8 : 4; 1350 const MCExpr *PCRelExpr = 1351 ARMMCExpr::CreateUpper16(MCBinaryExpr::CreateSub(GVSymExpr, 1352 MCBinaryExpr::CreateAdd(LabelSymExpr, 1353 MCConstantExpr::Create(PCAdj, OutContext), 1354 OutContext), OutContext), OutContext); 1355 TmpInst.addOperand(MCOperand::CreateExpr(PCRelExpr)); 1356 // Add predicate operands. 1357 TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL)); 1358 TmpInst.addOperand(MCOperand::CreateReg(0)); 1359 // Add 's' bit operand (always reg0 for this) 1360 TmpInst.addOperand(MCOperand::CreateReg(0)); 1361 EmitToStreamer(OutStreamer, TmpInst); 1362 return; 1363 } 1364 case ARM::tPICADD: { 1365 // This is a pseudo op for a label + instruction sequence, which looks like: 1366 // LPC0: 1367 // add r0, pc 1368 // This adds the address of LPC0 to r0. 1369 1370 // Emit the label. 1371 OutStreamer.EmitLabel(getPICLabel(DL->getPrivateGlobalPrefix(), 1372 getFunctionNumber(), MI->getOperand(2).getImm(), 1373 OutContext)); 1374 1375 // Form and emit the add. 1376 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tADDhirr) 1377 .addReg(MI->getOperand(0).getReg()) 1378 .addReg(MI->getOperand(0).getReg()) 1379 .addReg(ARM::PC) 1380 // Add predicate operands. 1381 .addImm(ARMCC::AL) 1382 .addReg(0)); 1383 return; 1384 } 1385 case ARM::PICADD: { 1386 // This is a pseudo op for a label + instruction sequence, which looks like: 1387 // LPC0: 1388 // add r0, pc, r0 1389 // This adds the address of LPC0 to r0. 1390 1391 // Emit the label. 1392 OutStreamer.EmitLabel(getPICLabel(DL->getPrivateGlobalPrefix(), 1393 getFunctionNumber(), MI->getOperand(2).getImm(), 1394 OutContext)); 1395 1396 // Form and emit the add. 1397 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::ADDrr) 1398 .addReg(MI->getOperand(0).getReg()) 1399 .addReg(ARM::PC) 1400 .addReg(MI->getOperand(1).getReg()) 1401 // Add predicate operands. 1402 .addImm(MI->getOperand(3).getImm()) 1403 .addReg(MI->getOperand(4).getReg()) 1404 // Add 's' bit operand (always reg0 for this) 1405 .addReg(0)); 1406 return; 1407 } 1408 case ARM::PICSTR: 1409 case ARM::PICSTRB: 1410 case ARM::PICSTRH: 1411 case ARM::PICLDR: 1412 case ARM::PICLDRB: 1413 case ARM::PICLDRH: 1414 case ARM::PICLDRSB: 1415 case ARM::PICLDRSH: { 1416 // This is a pseudo op for a label + instruction sequence, which looks like: 1417 // LPC0: 1418 // OP r0, [pc, r0] 1419 // The LCP0 label is referenced by a constant pool entry in order to get 1420 // a PC-relative address at the ldr instruction. 1421 1422 // Emit the label. 1423 OutStreamer.EmitLabel(getPICLabel(DL->getPrivateGlobalPrefix(), 1424 getFunctionNumber(), MI->getOperand(2).getImm(), 1425 OutContext)); 1426 1427 // Form and emit the load 1428 unsigned Opcode; 1429 switch (MI->getOpcode()) { 1430 default: 1431 llvm_unreachable("Unexpected opcode!"); 1432 case ARM::PICSTR: Opcode = ARM::STRrs; break; 1433 case ARM::PICSTRB: Opcode = ARM::STRBrs; break; 1434 case ARM::PICSTRH: Opcode = ARM::STRH; break; 1435 case ARM::PICLDR: Opcode = ARM::LDRrs; break; 1436 case ARM::PICLDRB: Opcode = ARM::LDRBrs; break; 1437 case ARM::PICLDRH: Opcode = ARM::LDRH; break; 1438 case ARM::PICLDRSB: Opcode = ARM::LDRSB; break; 1439 case ARM::PICLDRSH: Opcode = ARM::LDRSH; break; 1440 } 1441 EmitToStreamer(OutStreamer, MCInstBuilder(Opcode) 1442 .addReg(MI->getOperand(0).getReg()) 1443 .addReg(ARM::PC) 1444 .addReg(MI->getOperand(1).getReg()) 1445 .addImm(0) 1446 // Add predicate operands. 1447 .addImm(MI->getOperand(3).getImm()) 1448 .addReg(MI->getOperand(4).getReg())); 1449 1450 return; 1451 } 1452 case ARM::CONSTPOOL_ENTRY: { 1453 /// CONSTPOOL_ENTRY - This instruction represents a floating constant pool 1454 /// in the function. The first operand is the ID# for this instruction, the 1455 /// second is the index into the MachineConstantPool that this is, the third 1456 /// is the size in bytes of this constant pool entry. 1457 /// The required alignment is specified on the basic block holding this MI. 1458 unsigned LabelId = (unsigned)MI->getOperand(0).getImm(); 1459 unsigned CPIdx = (unsigned)MI->getOperand(1).getIndex(); 1460 1461 // If this is the first entry of the pool, mark it. 1462 if (!InConstantPool) { 1463 OutStreamer.EmitDataRegion(MCDR_DataRegion); 1464 InConstantPool = true; 1465 } 1466 1467 OutStreamer.EmitLabel(GetCPISymbol(LabelId)); 1468 1469 const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPIdx]; 1470 if (MCPE.isMachineConstantPoolEntry()) 1471 EmitMachineConstantPoolValue(MCPE.Val.MachineCPVal); 1472 else 1473 EmitGlobalConstant(MCPE.Val.ConstVal); 1474 return; 1475 } 1476 case ARM::t2BR_JT: { 1477 // Lower and emit the instruction itself, then the jump table following it. 1478 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tMOVr) 1479 .addReg(ARM::PC) 1480 .addReg(MI->getOperand(0).getReg()) 1481 // Add predicate operands. 1482 .addImm(ARMCC::AL) 1483 .addReg(0)); 1484 1485 // Output the data for the jump table itself 1486 EmitJump2Table(MI); 1487 return; 1488 } 1489 case ARM::t2TBB_JT: { 1490 // Lower and emit the instruction itself, then the jump table following it. 1491 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::t2TBB) 1492 .addReg(ARM::PC) 1493 .addReg(MI->getOperand(0).getReg()) 1494 // Add predicate operands. 1495 .addImm(ARMCC::AL) 1496 .addReg(0)); 1497 1498 // Output the data for the jump table itself 1499 EmitJump2Table(MI); 1500 // Make sure the next instruction is 2-byte aligned. 1501 EmitAlignment(1); 1502 return; 1503 } 1504 case ARM::t2TBH_JT: { 1505 // Lower and emit the instruction itself, then the jump table following it. 1506 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::t2TBH) 1507 .addReg(ARM::PC) 1508 .addReg(MI->getOperand(0).getReg()) 1509 // Add predicate operands. 1510 .addImm(ARMCC::AL) 1511 .addReg(0)); 1512 1513 // Output the data for the jump table itself 1514 EmitJump2Table(MI); 1515 return; 1516 } 1517 case ARM::tBR_JTr: 1518 case ARM::BR_JTr: { 1519 // Lower and emit the instruction itself, then the jump table following it. 1520 // mov pc, target 1521 MCInst TmpInst; 1522 unsigned Opc = MI->getOpcode() == ARM::BR_JTr ? 1523 ARM::MOVr : ARM::tMOVr; 1524 TmpInst.setOpcode(Opc); 1525 TmpInst.addOperand(MCOperand::CreateReg(ARM::PC)); 1526 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg())); 1527 // Add predicate operands. 1528 TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL)); 1529 TmpInst.addOperand(MCOperand::CreateReg(0)); 1530 // Add 's' bit operand (always reg0 for this) 1531 if (Opc == ARM::MOVr) 1532 TmpInst.addOperand(MCOperand::CreateReg(0)); 1533 EmitToStreamer(OutStreamer, TmpInst); 1534 1535 // Make sure the Thumb jump table is 4-byte aligned. 1536 if (Opc == ARM::tMOVr) 1537 EmitAlignment(2); 1538 1539 // Output the data for the jump table itself 1540 EmitJumpTable(MI); 1541 return; 1542 } 1543 case ARM::BR_JTm: { 1544 // Lower and emit the instruction itself, then the jump table following it. 1545 // ldr pc, target 1546 MCInst TmpInst; 1547 if (MI->getOperand(1).getReg() == 0) { 1548 // literal offset 1549 TmpInst.setOpcode(ARM::LDRi12); 1550 TmpInst.addOperand(MCOperand::CreateReg(ARM::PC)); 1551 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg())); 1552 TmpInst.addOperand(MCOperand::CreateImm(MI->getOperand(2).getImm())); 1553 } else { 1554 TmpInst.setOpcode(ARM::LDRrs); 1555 TmpInst.addOperand(MCOperand::CreateReg(ARM::PC)); 1556 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg())); 1557 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg())); 1558 TmpInst.addOperand(MCOperand::CreateImm(0)); 1559 } 1560 // Add predicate operands. 1561 TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL)); 1562 TmpInst.addOperand(MCOperand::CreateReg(0)); 1563 EmitToStreamer(OutStreamer, TmpInst); 1564 1565 // Output the data for the jump table itself 1566 EmitJumpTable(MI); 1567 return; 1568 } 1569 case ARM::BR_JTadd: { 1570 // Lower and emit the instruction itself, then the jump table following it. 1571 // add pc, target, idx 1572 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::ADDrr) 1573 .addReg(ARM::PC) 1574 .addReg(MI->getOperand(0).getReg()) 1575 .addReg(MI->getOperand(1).getReg()) 1576 // Add predicate operands. 1577 .addImm(ARMCC::AL) 1578 .addReg(0) 1579 // Add 's' bit operand (always reg0 for this) 1580 .addReg(0)); 1581 1582 // Output the data for the jump table itself 1583 EmitJumpTable(MI); 1584 return; 1585 } 1586 case ARM::TRAP: { 1587 // Non-Darwin binutils don't yet support the "trap" mnemonic. 1588 // FIXME: Remove this special case when they do. 1589 if (!Subtarget->isTargetMachO()) { 1590 //.long 0xe7ffdefe @ trap 1591 uint32_t Val = 0xe7ffdefeUL; 1592 OutStreamer.AddComment("trap"); 1593 OutStreamer.EmitIntValue(Val, 4); 1594 return; 1595 } 1596 break; 1597 } 1598 case ARM::TRAPNaCl: { 1599 //.long 0xe7fedef0 @ trap 1600 uint32_t Val = 0xe7fedef0UL; 1601 OutStreamer.AddComment("trap"); 1602 OutStreamer.EmitIntValue(Val, 4); 1603 return; 1604 } 1605 case ARM::tTRAP: { 1606 // Non-Darwin binutils don't yet support the "trap" mnemonic. 1607 // FIXME: Remove this special case when they do. 1608 if (!Subtarget->isTargetMachO()) { 1609 //.short 57086 @ trap 1610 uint16_t Val = 0xdefe; 1611 OutStreamer.AddComment("trap"); 1612 OutStreamer.EmitIntValue(Val, 2); 1613 return; 1614 } 1615 break; 1616 } 1617 case ARM::t2Int_eh_sjlj_setjmp: 1618 case ARM::t2Int_eh_sjlj_setjmp_nofp: 1619 case ARM::tInt_eh_sjlj_setjmp: { 1620 // Two incoming args: GPR:$src, GPR:$val 1621 // mov $val, pc 1622 // adds $val, #7 1623 // str $val, [$src, #4] 1624 // movs r0, #0 1625 // b 1f 1626 // movs r0, #1 1627 // 1: 1628 unsigned SrcReg = MI->getOperand(0).getReg(); 1629 unsigned ValReg = MI->getOperand(1).getReg(); 1630 MCSymbol *Label = GetARMSJLJEHLabel(); 1631 OutStreamer.AddComment("eh_setjmp begin"); 1632 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tMOVr) 1633 .addReg(ValReg) 1634 .addReg(ARM::PC) 1635 // Predicate. 1636 .addImm(ARMCC::AL) 1637 .addReg(0)); 1638 1639 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tADDi3) 1640 .addReg(ValReg) 1641 // 's' bit operand 1642 .addReg(ARM::CPSR) 1643 .addReg(ValReg) 1644 .addImm(7) 1645 // Predicate. 1646 .addImm(ARMCC::AL) 1647 .addReg(0)); 1648 1649 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tSTRi) 1650 .addReg(ValReg) 1651 .addReg(SrcReg) 1652 // The offset immediate is #4. The operand value is scaled by 4 for the 1653 // tSTR instruction. 1654 .addImm(1) 1655 // Predicate. 1656 .addImm(ARMCC::AL) 1657 .addReg(0)); 1658 1659 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tMOVi8) 1660 .addReg(ARM::R0) 1661 .addReg(ARM::CPSR) 1662 .addImm(0) 1663 // Predicate. 1664 .addImm(ARMCC::AL) 1665 .addReg(0)); 1666 1667 const MCExpr *SymbolExpr = MCSymbolRefExpr::Create(Label, OutContext); 1668 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tB) 1669 .addExpr(SymbolExpr) 1670 .addImm(ARMCC::AL) 1671 .addReg(0)); 1672 1673 OutStreamer.AddComment("eh_setjmp end"); 1674 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tMOVi8) 1675 .addReg(ARM::R0) 1676 .addReg(ARM::CPSR) 1677 .addImm(1) 1678 // Predicate. 1679 .addImm(ARMCC::AL) 1680 .addReg(0)); 1681 1682 OutStreamer.EmitLabel(Label); 1683 return; 1684 } 1685 1686 case ARM::Int_eh_sjlj_setjmp_nofp: 1687 case ARM::Int_eh_sjlj_setjmp: { 1688 // Two incoming args: GPR:$src, GPR:$val 1689 // add $val, pc, #8 1690 // str $val, [$src, #+4] 1691 // mov r0, #0 1692 // add pc, pc, #0 1693 // mov r0, #1 1694 unsigned SrcReg = MI->getOperand(0).getReg(); 1695 unsigned ValReg = MI->getOperand(1).getReg(); 1696 1697 OutStreamer.AddComment("eh_setjmp begin"); 1698 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::ADDri) 1699 .addReg(ValReg) 1700 .addReg(ARM::PC) 1701 .addImm(8) 1702 // Predicate. 1703 .addImm(ARMCC::AL) 1704 .addReg(0) 1705 // 's' bit operand (always reg0 for this). 1706 .addReg(0)); 1707 1708 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::STRi12) 1709 .addReg(ValReg) 1710 .addReg(SrcReg) 1711 .addImm(4) 1712 // Predicate. 1713 .addImm(ARMCC::AL) 1714 .addReg(0)); 1715 1716 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::MOVi) 1717 .addReg(ARM::R0) 1718 .addImm(0) 1719 // Predicate. 1720 .addImm(ARMCC::AL) 1721 .addReg(0) 1722 // 's' bit operand (always reg0 for this). 1723 .addReg(0)); 1724 1725 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::ADDri) 1726 .addReg(ARM::PC) 1727 .addReg(ARM::PC) 1728 .addImm(0) 1729 // Predicate. 1730 .addImm(ARMCC::AL) 1731 .addReg(0) 1732 // 's' bit operand (always reg0 for this). 1733 .addReg(0)); 1734 1735 OutStreamer.AddComment("eh_setjmp end"); 1736 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::MOVi) 1737 .addReg(ARM::R0) 1738 .addImm(1) 1739 // Predicate. 1740 .addImm(ARMCC::AL) 1741 .addReg(0) 1742 // 's' bit operand (always reg0 for this). 1743 .addReg(0)); 1744 return; 1745 } 1746 case ARM::Int_eh_sjlj_longjmp: { 1747 // ldr sp, [$src, #8] 1748 // ldr $scratch, [$src, #4] 1749 // ldr r7, [$src] 1750 // bx $scratch 1751 unsigned SrcReg = MI->getOperand(0).getReg(); 1752 unsigned ScratchReg = MI->getOperand(1).getReg(); 1753 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::LDRi12) 1754 .addReg(ARM::SP) 1755 .addReg(SrcReg) 1756 .addImm(8) 1757 // Predicate. 1758 .addImm(ARMCC::AL) 1759 .addReg(0)); 1760 1761 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::LDRi12) 1762 .addReg(ScratchReg) 1763 .addReg(SrcReg) 1764 .addImm(4) 1765 // Predicate. 1766 .addImm(ARMCC::AL) 1767 .addReg(0)); 1768 1769 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::LDRi12) 1770 .addReg(ARM::R7) 1771 .addReg(SrcReg) 1772 .addImm(0) 1773 // Predicate. 1774 .addImm(ARMCC::AL) 1775 .addReg(0)); 1776 1777 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::BX) 1778 .addReg(ScratchReg) 1779 // Predicate. 1780 .addImm(ARMCC::AL) 1781 .addReg(0)); 1782 return; 1783 } 1784 case ARM::tInt_eh_sjlj_longjmp: { 1785 // ldr $scratch, [$src, #8] 1786 // mov sp, $scratch 1787 // ldr $scratch, [$src, #4] 1788 // ldr r7, [$src] 1789 // bx $scratch 1790 unsigned SrcReg = MI->getOperand(0).getReg(); 1791 unsigned ScratchReg = MI->getOperand(1).getReg(); 1792 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tLDRi) 1793 .addReg(ScratchReg) 1794 .addReg(SrcReg) 1795 // The offset immediate is #8. The operand value is scaled by 4 for the 1796 // tLDR instruction. 1797 .addImm(2) 1798 // Predicate. 1799 .addImm(ARMCC::AL) 1800 .addReg(0)); 1801 1802 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tMOVr) 1803 .addReg(ARM::SP) 1804 .addReg(ScratchReg) 1805 // Predicate. 1806 .addImm(ARMCC::AL) 1807 .addReg(0)); 1808 1809 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tLDRi) 1810 .addReg(ScratchReg) 1811 .addReg(SrcReg) 1812 .addImm(1) 1813 // Predicate. 1814 .addImm(ARMCC::AL) 1815 .addReg(0)); 1816 1817 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tLDRi) 1818 .addReg(ARM::R7) 1819 .addReg(SrcReg) 1820 .addImm(0) 1821 // Predicate. 1822 .addImm(ARMCC::AL) 1823 .addReg(0)); 1824 1825 EmitToStreamer(OutStreamer, MCInstBuilder(ARM::tBX) 1826 .addReg(ScratchReg) 1827 // Predicate. 1828 .addImm(ARMCC::AL) 1829 .addReg(0)); 1830 return; 1831 } 1832 } 1833 1834 MCInst TmpInst; 1835 LowerARMMachineInstrToMCInst(MI, TmpInst, *this); 1836 1837 EmitToStreamer(OutStreamer, TmpInst); 1838 } 1839 1840 //===----------------------------------------------------------------------===// 1841 // Target Registry Stuff 1842 //===----------------------------------------------------------------------===// 1843 1844 // Force static initialization. 1845 extern "C" void LLVMInitializeARMAsmPrinter() { 1846 RegisterAsmPrinter<ARMAsmPrinter> X(TheARMLETarget); 1847 RegisterAsmPrinter<ARMAsmPrinter> Y(TheARMBETarget); 1848 RegisterAsmPrinter<ARMAsmPrinter> A(TheThumbLETarget); 1849 RegisterAsmPrinter<ARMAsmPrinter> B(TheThumbBETarget); 1850 } 1851