1 //===- MipsAsmPrinter.cpp - Mips LLVM Assembly Printer --------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file contains a printer that converts from our internal representation 10 // of machine-dependent LLVM code to GAS-format MIPS assembly language. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "MipsAsmPrinter.h" 15 #include "MCTargetDesc/MipsABIInfo.h" 16 #include "MCTargetDesc/MipsBaseInfo.h" 17 #include "MCTargetDesc/MipsInstPrinter.h" 18 #include "MCTargetDesc/MipsMCNaCl.h" 19 #include "MCTargetDesc/MipsMCTargetDesc.h" 20 #include "Mips.h" 21 #include "MipsMCInstLower.h" 22 #include "MipsMachineFunction.h" 23 #include "MipsSubtarget.h" 24 #include "MipsTargetMachine.h" 25 #include "MipsTargetStreamer.h" 26 #include "TargetInfo/MipsTargetInfo.h" 27 #include "llvm/ADT/SmallString.h" 28 #include "llvm/ADT/StringRef.h" 29 #include "llvm/ADT/Twine.h" 30 #include "llvm/BinaryFormat/ELF.h" 31 #include "llvm/CodeGen/MachineBasicBlock.h" 32 #include "llvm/CodeGen/MachineConstantPool.h" 33 #include "llvm/CodeGen/MachineFrameInfo.h" 34 #include "llvm/CodeGen/MachineFunction.h" 35 #include "llvm/CodeGen/MachineInstr.h" 36 #include "llvm/CodeGen/MachineJumpTableInfo.h" 37 #include "llvm/CodeGen/MachineOperand.h" 38 #include "llvm/CodeGen/TargetRegisterInfo.h" 39 #include "llvm/CodeGen/TargetSubtargetInfo.h" 40 #include "llvm/IR/Attributes.h" 41 #include "llvm/IR/BasicBlock.h" 42 #include "llvm/IR/DataLayout.h" 43 #include "llvm/IR/Function.h" 44 #include "llvm/IR/InlineAsm.h" 45 #include "llvm/IR/Instructions.h" 46 #include "llvm/IR/Module.h" 47 #include "llvm/MC/MCContext.h" 48 #include "llvm/MC/MCExpr.h" 49 #include "llvm/MC/MCInst.h" 50 #include "llvm/MC/MCInstBuilder.h" 51 #include "llvm/MC/MCObjectFileInfo.h" 52 #include "llvm/MC/MCSectionELF.h" 53 #include "llvm/MC/MCSymbol.h" 54 #include "llvm/MC/MCSymbolELF.h" 55 #include "llvm/MC/TargetRegistry.h" 56 #include "llvm/Support/Casting.h" 57 #include "llvm/Support/ErrorHandling.h" 58 #include "llvm/Support/raw_ostream.h" 59 #include "llvm/Target/TargetLoweringObjectFile.h" 60 #include "llvm/Target/TargetMachine.h" 61 #include "llvm/TargetParser/Triple.h" 62 #include <cassert> 63 #include <cstdint> 64 #include <map> 65 #include <memory> 66 #include <string> 67 #include <vector> 68 69 using namespace llvm; 70 71 #define DEBUG_TYPE "mips-asm-printer" 72 73 extern cl::opt<bool> EmitJalrReloc; 74 75 MipsTargetStreamer &MipsAsmPrinter::getTargetStreamer() const { 76 return static_cast<MipsTargetStreamer &>(*OutStreamer->getTargetStreamer()); 77 } 78 79 bool MipsAsmPrinter::runOnMachineFunction(MachineFunction &MF) { 80 Subtarget = &MF.getSubtarget<MipsSubtarget>(); 81 82 MipsFI = MF.getInfo<MipsFunctionInfo>(); 83 if (Subtarget->inMips16Mode()) 84 for (const auto &I : MipsFI->StubsNeeded) { 85 const char *Symbol = I.first; 86 const Mips16HardFloatInfo::FuncSignature *Signature = I.second; 87 if (StubsNeeded.find(Symbol) == StubsNeeded.end()) 88 StubsNeeded[Symbol] = Signature; 89 } 90 MCP = MF.getConstantPool(); 91 92 // In NaCl, all indirect jump targets must be aligned to bundle size. 93 if (Subtarget->isTargetNaCl()) 94 NaClAlignIndirectJumpTargets(MF); 95 96 AsmPrinter::runOnMachineFunction(MF); 97 98 emitXRayTable(); 99 100 return true; 101 } 102 103 bool MipsAsmPrinter::lowerOperand(const MachineOperand &MO, MCOperand &MCOp) { 104 MCOp = MCInstLowering.LowerOperand(MO); 105 return MCOp.isValid(); 106 } 107 108 #include "MipsGenMCPseudoLowering.inc" 109 110 // Lower PseudoReturn/PseudoIndirectBranch/PseudoIndirectBranch64 to JR, JR_MM, 111 // JALR, or JALR64 as appropriate for the target. 112 void MipsAsmPrinter::emitPseudoIndirectBranch(MCStreamer &OutStreamer, 113 const MachineInstr *MI) { 114 bool HasLinkReg = false; 115 bool InMicroMipsMode = Subtarget->inMicroMipsMode(); 116 MCInst TmpInst0; 117 118 if (Subtarget->hasMips64r6()) { 119 // MIPS64r6 should use (JALR64 ZERO_64, $rs) 120 TmpInst0.setOpcode(Mips::JALR64); 121 HasLinkReg = true; 122 } else if (Subtarget->hasMips32r6()) { 123 // MIPS32r6 should use (JALR ZERO, $rs) 124 if (InMicroMipsMode) 125 TmpInst0.setOpcode(Mips::JRC16_MMR6); 126 else { 127 TmpInst0.setOpcode(Mips::JALR); 128 HasLinkReg = true; 129 } 130 } else if (Subtarget->inMicroMipsMode()) 131 // microMIPS should use (JR_MM $rs) 132 TmpInst0.setOpcode(Mips::JR_MM); 133 else { 134 // Everything else should use (JR $rs) 135 TmpInst0.setOpcode(Mips::JR); 136 } 137 138 MCOperand MCOp; 139 140 if (HasLinkReg) { 141 unsigned ZeroReg = Subtarget->isGP64bit() ? Mips::ZERO_64 : Mips::ZERO; 142 TmpInst0.addOperand(MCOperand::createReg(ZeroReg)); 143 } 144 145 lowerOperand(MI->getOperand(0), MCOp); 146 TmpInst0.addOperand(MCOp); 147 148 EmitToStreamer(OutStreamer, TmpInst0); 149 } 150 151 // If there is an MO_JALR operand, insert: 152 // 153 // .reloc tmplabel, R_{MICRO}MIPS_JALR, symbol 154 // tmplabel: 155 // 156 // This is an optimization hint for the linker which may then replace 157 // an indirect call with a direct branch. 158 static void emitDirectiveRelocJalr(const MachineInstr &MI, 159 MCContext &OutContext, 160 TargetMachine &TM, 161 MCStreamer &OutStreamer, 162 const MipsSubtarget &Subtarget) { 163 for (const MachineOperand &MO : 164 llvm::drop_begin(MI.operands(), MI.getDesc().getNumOperands())) { 165 if (MO.isMCSymbol() && (MO.getTargetFlags() & MipsII::MO_JALR)) { 166 MCSymbol *Callee = MO.getMCSymbol(); 167 if (Callee && !Callee->getName().empty()) { 168 MCSymbol *OffsetLabel = OutContext.createTempSymbol(); 169 const MCExpr *OffsetExpr = 170 MCSymbolRefExpr::create(OffsetLabel, OutContext); 171 const MCExpr *CaleeExpr = 172 MCSymbolRefExpr::create(Callee, OutContext); 173 OutStreamer.emitRelocDirective( 174 *OffsetExpr, 175 Subtarget.inMicroMipsMode() ? "R_MICROMIPS_JALR" : "R_MIPS_JALR", 176 CaleeExpr, SMLoc(), *TM.getMCSubtargetInfo()); 177 OutStreamer.emitLabel(OffsetLabel); 178 return; 179 } 180 } 181 } 182 } 183 184 void MipsAsmPrinter::emitInstruction(const MachineInstr *MI) { 185 // FIXME: Enable feature predicate checks once all the test pass. 186 // Mips_MC::verifyInstructionPredicates(MI->getOpcode(), 187 // getSubtargetInfo().getFeatureBits()); 188 189 MipsTargetStreamer &TS = getTargetStreamer(); 190 unsigned Opc = MI->getOpcode(); 191 TS.forbidModuleDirective(); 192 193 if (MI->isDebugValue()) { 194 SmallString<128> Str; 195 raw_svector_ostream OS(Str); 196 197 PrintDebugValueComment(MI, OS); 198 return; 199 } 200 if (MI->isDebugLabel()) 201 return; 202 203 // If we just ended a constant pool, mark it as such. 204 if (InConstantPool && Opc != Mips::CONSTPOOL_ENTRY) { 205 OutStreamer->emitDataRegion(MCDR_DataRegionEnd); 206 InConstantPool = false; 207 } 208 if (Opc == Mips::CONSTPOOL_ENTRY) { 209 // CONSTPOOL_ENTRY - This instruction represents a floating 210 // constant pool in the function. The first operand is the ID# 211 // for this instruction, the second is the index into the 212 // MachineConstantPool that this is, the third is the size in 213 // bytes of this constant pool entry. 214 // The required alignment is specified on the basic block holding this MI. 215 // 216 unsigned LabelId = (unsigned)MI->getOperand(0).getImm(); 217 unsigned CPIdx = (unsigned)MI->getOperand(1).getIndex(); 218 219 // If this is the first entry of the pool, mark it. 220 if (!InConstantPool) { 221 OutStreamer->emitDataRegion(MCDR_DataRegion); 222 InConstantPool = true; 223 } 224 225 OutStreamer->emitLabel(GetCPISymbol(LabelId)); 226 227 const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPIdx]; 228 if (MCPE.isMachineConstantPoolEntry()) 229 emitMachineConstantPoolValue(MCPE.Val.MachineCPVal); 230 else 231 emitGlobalConstant(MF->getDataLayout(), MCPE.Val.ConstVal); 232 return; 233 } 234 235 switch (Opc) { 236 case Mips::PATCHABLE_FUNCTION_ENTER: 237 LowerPATCHABLE_FUNCTION_ENTER(*MI); 238 return; 239 case Mips::PATCHABLE_FUNCTION_EXIT: 240 LowerPATCHABLE_FUNCTION_EXIT(*MI); 241 return; 242 case Mips::PATCHABLE_TAIL_CALL: 243 LowerPATCHABLE_TAIL_CALL(*MI); 244 return; 245 } 246 247 if (EmitJalrReloc && 248 (MI->isReturn() || MI->isCall() || MI->isIndirectBranch())) { 249 emitDirectiveRelocJalr(*MI, OutContext, TM, *OutStreamer, *Subtarget); 250 } 251 252 MachineBasicBlock::const_instr_iterator I = MI->getIterator(); 253 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 254 255 do { 256 // Do any auto-generated pseudo lowerings. 257 if (emitPseudoExpansionLowering(*OutStreamer, &*I)) 258 continue; 259 260 // Skip the BUNDLE pseudo instruction and lower the contents 261 if (I->isBundle()) 262 continue; 263 264 if (I->getOpcode() == Mips::PseudoReturn || 265 I->getOpcode() == Mips::PseudoReturn64 || 266 I->getOpcode() == Mips::PseudoIndirectBranch || 267 I->getOpcode() == Mips::PseudoIndirectBranch64 || 268 I->getOpcode() == Mips::TAILCALLREG || 269 I->getOpcode() == Mips::TAILCALLREG64) { 270 emitPseudoIndirectBranch(*OutStreamer, &*I); 271 continue; 272 } 273 274 // The inMips16Mode() test is not permanent. 275 // Some instructions are marked as pseudo right now which 276 // would make the test fail for the wrong reason but 277 // that will be fixed soon. We need this here because we are 278 // removing another test for this situation downstream in the 279 // callchain. 280 // 281 if (I->isPseudo() && !Subtarget->inMips16Mode() 282 && !isLongBranchPseudo(I->getOpcode())) 283 llvm_unreachable("Pseudo opcode found in emitInstruction()"); 284 285 MCInst TmpInst0; 286 MCInstLowering.Lower(&*I, TmpInst0); 287 EmitToStreamer(*OutStreamer, TmpInst0); 288 } while ((++I != E) && I->isInsideBundle()); // Delay slot check 289 } 290 291 //===----------------------------------------------------------------------===// 292 // 293 // Mips Asm Directives 294 // 295 // -- Frame directive "frame Stackpointer, Stacksize, RARegister" 296 // Describe the stack frame. 297 // 298 // -- Mask directives "(f)mask bitmask, offset" 299 // Tells the assembler which registers are saved and where. 300 // bitmask - contain a little endian bitset indicating which registers are 301 // saved on function prologue (e.g. with a 0x80000000 mask, the 302 // assembler knows the register 31 (RA) is saved at prologue. 303 // offset - the position before stack pointer subtraction indicating where 304 // the first saved register on prologue is located. (e.g. with a 305 // 306 // Consider the following function prologue: 307 // 308 // .frame $fp,48,$ra 309 // .mask 0xc0000000,-8 310 // addiu $sp, $sp, -48 311 // sw $ra, 40($sp) 312 // sw $fp, 36($sp) 313 // 314 // With a 0xc0000000 mask, the assembler knows the register 31 (RA) and 315 // 30 (FP) are saved at prologue. As the save order on prologue is from 316 // left to right, RA is saved first. A -8 offset means that after the 317 // stack pointer subtration, the first register in the mask (RA) will be 318 // saved at address 48-8=40. 319 // 320 //===----------------------------------------------------------------------===// 321 322 //===----------------------------------------------------------------------===// 323 // Mask directives 324 //===----------------------------------------------------------------------===// 325 326 // Create a bitmask with all callee saved registers for CPU or Floating Point 327 // registers. For CPU registers consider RA, GP and FP for saving if necessary. 328 void MipsAsmPrinter::printSavedRegsBitmask() { 329 // CPU and FPU Saved Registers Bitmasks 330 unsigned CPUBitmask = 0, FPUBitmask = 0; 331 int CPUTopSavedRegOff, FPUTopSavedRegOff; 332 333 // Set the CPU and FPU Bitmasks 334 const MachineFrameInfo &MFI = MF->getFrameInfo(); 335 const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); 336 const std::vector<CalleeSavedInfo> &CSI = MFI.getCalleeSavedInfo(); 337 // size of stack area to which FP callee-saved regs are saved. 338 unsigned CPURegSize = TRI->getRegSizeInBits(Mips::GPR32RegClass) / 8; 339 unsigned FGR32RegSize = TRI->getRegSizeInBits(Mips::FGR32RegClass) / 8; 340 unsigned AFGR64RegSize = TRI->getRegSizeInBits(Mips::AFGR64RegClass) / 8; 341 bool HasAFGR64Reg = false; 342 unsigned CSFPRegsSize = 0; 343 344 for (const auto &I : CSI) { 345 Register Reg = I.getReg(); 346 unsigned RegNum = TRI->getEncodingValue(Reg); 347 348 // If it's a floating point register, set the FPU Bitmask. 349 // If it's a general purpose register, set the CPU Bitmask. 350 if (Mips::FGR32RegClass.contains(Reg)) { 351 FPUBitmask |= (1 << RegNum); 352 CSFPRegsSize += FGR32RegSize; 353 } else if (Mips::AFGR64RegClass.contains(Reg)) { 354 FPUBitmask |= (3 << RegNum); 355 CSFPRegsSize += AFGR64RegSize; 356 HasAFGR64Reg = true; 357 } else if (Mips::GPR32RegClass.contains(Reg)) 358 CPUBitmask |= (1 << RegNum); 359 } 360 361 // FP Regs are saved right below where the virtual frame pointer points to. 362 FPUTopSavedRegOff = FPUBitmask ? 363 (HasAFGR64Reg ? -AFGR64RegSize : -FGR32RegSize) : 0; 364 365 // CPU Regs are saved below FP Regs. 366 CPUTopSavedRegOff = CPUBitmask ? -CSFPRegsSize - CPURegSize : 0; 367 368 MipsTargetStreamer &TS = getTargetStreamer(); 369 // Print CPUBitmask 370 TS.emitMask(CPUBitmask, CPUTopSavedRegOff); 371 372 // Print FPUBitmask 373 TS.emitFMask(FPUBitmask, FPUTopSavedRegOff); 374 } 375 376 //===----------------------------------------------------------------------===// 377 // Frame and Set directives 378 //===----------------------------------------------------------------------===// 379 380 /// Frame Directive 381 void MipsAsmPrinter::emitFrameDirective() { 382 const TargetRegisterInfo &RI = *MF->getSubtarget().getRegisterInfo(); 383 384 Register stackReg = RI.getFrameRegister(*MF); 385 unsigned returnReg = RI.getRARegister(); 386 unsigned stackSize = MF->getFrameInfo().getStackSize(); 387 388 getTargetStreamer().emitFrame(stackReg, stackSize, returnReg); 389 } 390 391 /// Emit Set directives. 392 const char *MipsAsmPrinter::getCurrentABIString() const { 393 switch (static_cast<MipsTargetMachine &>(TM).getABI().GetEnumValue()) { 394 case MipsABIInfo::ABI::O32: return "abi32"; 395 case MipsABIInfo::ABI::N32: return "abiN32"; 396 case MipsABIInfo::ABI::N64: return "abi64"; 397 default: llvm_unreachable("Unknown Mips ABI"); 398 } 399 } 400 401 void MipsAsmPrinter::emitFunctionEntryLabel() { 402 MipsTargetStreamer &TS = getTargetStreamer(); 403 404 // NaCl sandboxing requires that indirect call instructions are masked. 405 // This means that function entry points should be bundle-aligned. 406 if (Subtarget->isTargetNaCl()) 407 emitAlignment(std::max(MF->getAlignment(), MIPS_NACL_BUNDLE_ALIGN)); 408 409 if (Subtarget->inMicroMipsMode()) { 410 TS.emitDirectiveSetMicroMips(); 411 TS.setUsesMicroMips(); 412 TS.updateABIInfo(*Subtarget); 413 } else 414 TS.emitDirectiveSetNoMicroMips(); 415 416 if (Subtarget->inMips16Mode()) 417 TS.emitDirectiveSetMips16(); 418 else 419 TS.emitDirectiveSetNoMips16(); 420 421 TS.emitDirectiveEnt(*CurrentFnSym); 422 OutStreamer->emitLabel(CurrentFnSym); 423 } 424 425 /// EmitFunctionBodyStart - Targets can override this to emit stuff before 426 /// the first basic block in the function. 427 void MipsAsmPrinter::emitFunctionBodyStart() { 428 MipsTargetStreamer &TS = getTargetStreamer(); 429 430 MCInstLowering.Initialize(&MF->getContext()); 431 432 bool IsNakedFunction = MF->getFunction().hasFnAttribute(Attribute::Naked); 433 if (!IsNakedFunction) 434 emitFrameDirective(); 435 436 if (!IsNakedFunction) 437 printSavedRegsBitmask(); 438 439 if (!Subtarget->inMips16Mode()) { 440 TS.emitDirectiveSetNoReorder(); 441 TS.emitDirectiveSetNoMacro(); 442 TS.emitDirectiveSetNoAt(); 443 } 444 } 445 446 /// EmitFunctionBodyEnd - Targets can override this to emit stuff after 447 /// the last basic block in the function. 448 void MipsAsmPrinter::emitFunctionBodyEnd() { 449 MipsTargetStreamer &TS = getTargetStreamer(); 450 451 // There are instruction for this macros, but they must 452 // always be at the function end, and we can't emit and 453 // break with BB logic. 454 if (!Subtarget->inMips16Mode()) { 455 TS.emitDirectiveSetAt(); 456 TS.emitDirectiveSetMacro(); 457 TS.emitDirectiveSetReorder(); 458 } 459 TS.emitDirectiveEnd(CurrentFnSym->getName()); 460 // Make sure to terminate any constant pools that were at the end 461 // of the function. 462 if (!InConstantPool) 463 return; 464 InConstantPool = false; 465 OutStreamer->emitDataRegion(MCDR_DataRegionEnd); 466 } 467 468 void MipsAsmPrinter::emitBasicBlockEnd(const MachineBasicBlock &MBB) { 469 AsmPrinter::emitBasicBlockEnd(MBB); 470 MipsTargetStreamer &TS = getTargetStreamer(); 471 if (MBB.empty()) 472 TS.emitDirectiveInsn(); 473 } 474 475 // Print out an operand for an inline asm expression. 476 bool MipsAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum, 477 const char *ExtraCode, raw_ostream &O) { 478 // Does this asm operand have a single letter operand modifier? 479 if (ExtraCode && ExtraCode[0]) { 480 if (ExtraCode[1] != 0) return true; // Unknown modifier. 481 482 const MachineOperand &MO = MI->getOperand(OpNum); 483 switch (ExtraCode[0]) { 484 default: 485 // See if this is a generic print operand 486 return AsmPrinter::PrintAsmOperand(MI, OpNum, ExtraCode, O); 487 case 'X': // hex const int 488 if (!MO.isImm()) 489 return true; 490 O << "0x" << Twine::utohexstr(MO.getImm()); 491 return false; 492 case 'x': // hex const int (low 16 bits) 493 if (!MO.isImm()) 494 return true; 495 O << "0x" << Twine::utohexstr(MO.getImm() & 0xffff); 496 return false; 497 case 'd': // decimal const int 498 if (!MO.isImm()) 499 return true; 500 O << MO.getImm(); 501 return false; 502 case 'm': // decimal const int minus 1 503 if (!MO.isImm()) 504 return true; 505 O << MO.getImm() - 1; 506 return false; 507 case 'y': // exact log2 508 if (!MO.isImm()) 509 return true; 510 if (!isPowerOf2_64(MO.getImm())) 511 return true; 512 O << Log2_64(MO.getImm()); 513 return false; 514 case 'z': 515 // $0 if zero, regular printing otherwise 516 if (MO.isImm() && MO.getImm() == 0) { 517 O << "$0"; 518 return false; 519 } 520 // If not, call printOperand as normal. 521 break; 522 case 'D': // Second part of a double word register operand 523 case 'L': // Low order register of a double word register operand 524 case 'M': // High order register of a double word register operand 525 { 526 if (OpNum == 0) 527 return true; 528 const MachineOperand &FlagsOP = MI->getOperand(OpNum - 1); 529 if (!FlagsOP.isImm()) 530 return true; 531 const InlineAsm::Flag Flags(FlagsOP.getImm()); 532 const unsigned NumVals = Flags.getNumOperandRegisters(); 533 // Number of registers represented by this operand. We are looking 534 // for 2 for 32 bit mode and 1 for 64 bit mode. 535 if (NumVals != 2) { 536 if (Subtarget->isGP64bit() && NumVals == 1 && MO.isReg()) { 537 Register Reg = MO.getReg(); 538 O << '$' << MipsInstPrinter::getRegisterName(Reg); 539 return false; 540 } 541 return true; 542 } 543 544 unsigned RegOp = OpNum; 545 if (!Subtarget->isGP64bit()){ 546 // Endianness reverses which register holds the high or low value 547 // between M and L. 548 switch(ExtraCode[0]) { 549 case 'M': 550 RegOp = (Subtarget->isLittle()) ? OpNum + 1 : OpNum; 551 break; 552 case 'L': 553 RegOp = (Subtarget->isLittle()) ? OpNum : OpNum + 1; 554 break; 555 case 'D': // Always the second part 556 RegOp = OpNum + 1; 557 } 558 if (RegOp >= MI->getNumOperands()) 559 return true; 560 const MachineOperand &MO = MI->getOperand(RegOp); 561 if (!MO.isReg()) 562 return true; 563 Register Reg = MO.getReg(); 564 O << '$' << MipsInstPrinter::getRegisterName(Reg); 565 return false; 566 } 567 break; 568 } 569 case 'w': { 570 MCRegister w = getMSARegFromFReg(MO.getReg()); 571 if (w != Mips::NoRegister) { 572 O << '$' << MipsInstPrinter::getRegisterName(w); 573 return false; 574 } 575 break; 576 } 577 } 578 } 579 580 printOperand(MI, OpNum, O); 581 return false; 582 } 583 584 bool MipsAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, 585 unsigned OpNum, 586 const char *ExtraCode, 587 raw_ostream &O) { 588 assert(OpNum + 1 < MI->getNumOperands() && "Insufficient operands"); 589 const MachineOperand &BaseMO = MI->getOperand(OpNum); 590 const MachineOperand &OffsetMO = MI->getOperand(OpNum + 1); 591 assert(BaseMO.isReg() && 592 "Unexpected base pointer for inline asm memory operand."); 593 assert(OffsetMO.isImm() && 594 "Unexpected offset for inline asm memory operand."); 595 int Offset = OffsetMO.getImm(); 596 597 // Currently we are expecting either no ExtraCode or 'D','M','L'. 598 if (ExtraCode) { 599 switch (ExtraCode[0]) { 600 case 'D': 601 Offset += 4; 602 break; 603 case 'M': 604 if (Subtarget->isLittle()) 605 Offset += 4; 606 break; 607 case 'L': 608 if (!Subtarget->isLittle()) 609 Offset += 4; 610 break; 611 default: 612 return true; // Unknown modifier. 613 } 614 } 615 616 O << Offset << "($" << MipsInstPrinter::getRegisterName(BaseMO.getReg()) 617 << ")"; 618 619 return false; 620 } 621 622 void MipsAsmPrinter::printOperand(const MachineInstr *MI, int opNum, 623 raw_ostream &O) { 624 const MachineOperand &MO = MI->getOperand(opNum); 625 bool closeP = false; 626 627 if (MO.getTargetFlags()) 628 closeP = true; 629 630 switch(MO.getTargetFlags()) { 631 case MipsII::MO_GPREL: O << "%gp_rel("; break; 632 case MipsII::MO_GOT_CALL: O << "%call16("; break; 633 case MipsII::MO_GOT: O << "%got("; break; 634 case MipsII::MO_ABS_HI: O << "%hi("; break; 635 case MipsII::MO_ABS_LO: O << "%lo("; break; 636 case MipsII::MO_HIGHER: O << "%higher("; break; 637 case MipsII::MO_HIGHEST: O << "%highest(("; break; 638 case MipsII::MO_TLSGD: O << "%tlsgd("; break; 639 case MipsII::MO_GOTTPREL: O << "%gottprel("; break; 640 case MipsII::MO_TPREL_HI: O << "%tprel_hi("; break; 641 case MipsII::MO_TPREL_LO: O << "%tprel_lo("; break; 642 case MipsII::MO_GPOFF_HI: O << "%hi(%neg(%gp_rel("; break; 643 case MipsII::MO_GPOFF_LO: O << "%lo(%neg(%gp_rel("; break; 644 case MipsII::MO_GOT_DISP: O << "%got_disp("; break; 645 case MipsII::MO_GOT_PAGE: O << "%got_page("; break; 646 case MipsII::MO_GOT_OFST: O << "%got_ofst("; break; 647 } 648 649 switch (MO.getType()) { 650 case MachineOperand::MO_Register: 651 O << '$' 652 << StringRef(MipsInstPrinter::getRegisterName(MO.getReg())).lower(); 653 break; 654 655 case MachineOperand::MO_Immediate: 656 O << MO.getImm(); 657 break; 658 659 case MachineOperand::MO_MachineBasicBlock: 660 MO.getMBB()->getSymbol()->print(O, MAI); 661 return; 662 663 case MachineOperand::MO_GlobalAddress: 664 PrintSymbolOperand(MO, O); 665 break; 666 667 case MachineOperand::MO_BlockAddress: { 668 MCSymbol *BA = GetBlockAddressSymbol(MO.getBlockAddress()); 669 O << BA->getName(); 670 break; 671 } 672 673 case MachineOperand::MO_ConstantPoolIndex: 674 O << getDataLayout().getPrivateGlobalPrefix() << "CPI" 675 << getFunctionNumber() << "_" << MO.getIndex(); 676 if (MO.getOffset()) 677 O << "+" << MO.getOffset(); 678 break; 679 680 default: 681 llvm_unreachable("<unknown operand type>"); 682 } 683 684 if (closeP) O << ")"; 685 } 686 687 void MipsAsmPrinter:: 688 printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O) { 689 // Load/Store memory operands -- imm($reg) 690 // If PIC target the target is loaded as the 691 // pattern lw $25,%call16($28) 692 693 // opNum can be invalid if instruction has reglist as operand. 694 // MemOperand is always last operand of instruction (base + offset). 695 switch (MI->getOpcode()) { 696 default: 697 break; 698 case Mips::SWM32_MM: 699 case Mips::LWM32_MM: 700 opNum = MI->getNumOperands() - 2; 701 break; 702 } 703 704 printOperand(MI, opNum+1, O); 705 O << "("; 706 printOperand(MI, opNum, O); 707 O << ")"; 708 } 709 710 void MipsAsmPrinter:: 711 printMemOperandEA(const MachineInstr *MI, int opNum, raw_ostream &O) { 712 // when using stack locations for not load/store instructions 713 // print the same way as all normal 3 operand instructions. 714 printOperand(MI, opNum, O); 715 O << ", "; 716 printOperand(MI, opNum+1, O); 717 } 718 719 void MipsAsmPrinter:: 720 printFCCOperand(const MachineInstr *MI, int opNum, raw_ostream &O, 721 const char *Modifier) { 722 const MachineOperand &MO = MI->getOperand(opNum); 723 O << Mips::MipsFCCToString((Mips::CondCode)MO.getImm()); 724 } 725 726 void MipsAsmPrinter:: 727 printRegisterList(const MachineInstr *MI, int opNum, raw_ostream &O) { 728 for (int i = opNum, e = MI->getNumOperands(); i != e; ++i) { 729 if (i != opNum) O << ", "; 730 printOperand(MI, i, O); 731 } 732 } 733 734 void MipsAsmPrinter::emitStartOfAsmFile(Module &M) { 735 MipsTargetStreamer &TS = getTargetStreamer(); 736 737 // MipsTargetStreamer has an initialization order problem when emitting an 738 // object file directly (see MipsTargetELFStreamer for full details). Work 739 // around it by re-initializing the PIC state here. 740 TS.setPic(OutContext.getObjectFileInfo()->isPositionIndependent()); 741 742 // Try to get target-features from the first function. 743 StringRef FS = TM.getTargetFeatureString(); 744 Module::iterator F = M.begin(); 745 if (FS.empty() && M.size() && F->hasFnAttribute("target-features")) 746 FS = F->getFnAttribute("target-features").getValueAsString(); 747 748 // Compute MIPS architecture attributes based on the default subtarget 749 // that we'd have constructed. 750 // FIXME: For ifunc related functions we could iterate over and look 751 // for a feature string that doesn't match the default one. 752 const Triple &TT = TM.getTargetTriple(); 753 StringRef CPU = MIPS_MC::selectMipsCPU(TT, TM.getTargetCPU()); 754 const MipsTargetMachine &MTM = static_cast<const MipsTargetMachine &>(TM); 755 const MipsSubtarget STI(TT, CPU, FS, MTM.isLittleEndian(), MTM, std::nullopt); 756 757 bool IsABICalls = STI.isABICalls(); 758 const MipsABIInfo &ABI = MTM.getABI(); 759 if (IsABICalls) { 760 TS.emitDirectiveAbiCalls(); 761 // FIXME: This condition should be a lot more complicated that it is here. 762 // Ideally it should test for properties of the ABI and not the ABI 763 // itself. 764 // For the moment, I'm only correcting enough to make MIPS-IV work. 765 if (!isPositionIndependent() && STI.hasSym32()) 766 TS.emitDirectiveOptionPic0(); 767 } 768 769 // Tell the assembler which ABI we are using 770 std::string SectionName = std::string(".mdebug.") + getCurrentABIString(); 771 OutStreamer->switchSection( 772 OutContext.getELFSection(SectionName, ELF::SHT_PROGBITS, 0)); 773 774 // NaN: At the moment we only support: 775 // 1. .nan legacy (default) 776 // 2. .nan 2008 777 STI.isNaN2008() ? TS.emitDirectiveNaN2008() 778 : TS.emitDirectiveNaNLegacy(); 779 780 // TODO: handle O64 ABI 781 782 TS.updateABIInfo(STI); 783 784 // We should always emit a '.module fp=...' but binutils 2.24 does not accept 785 // it. We therefore emit it when it contradicts the ABI defaults (-mfpxx or 786 // -mfp64) and omit it otherwise. 787 if ((ABI.IsO32() && (STI.isABI_FPXX() || STI.isFP64bit())) || 788 STI.useSoftFloat()) 789 TS.emitDirectiveModuleFP(); 790 791 // We should always emit a '.module [no]oddspreg' but binutils 2.24 does not 792 // accept it. We therefore emit it when it contradicts the default or an 793 // option has changed the default (i.e. FPXX) and omit it otherwise. 794 if (ABI.IsO32() && (!STI.useOddSPReg() || STI.isABI_FPXX())) 795 TS.emitDirectiveModuleOddSPReg(); 796 797 // Switch to the .text section. 798 OutStreamer->switchSection(getObjFileLowering().getTextSection()); 799 } 800 801 void MipsAsmPrinter::emitInlineAsmStart() const { 802 MipsTargetStreamer &TS = getTargetStreamer(); 803 804 // GCC's choice of assembler options for inline assembly code ('at', 'macro' 805 // and 'reorder') is different from LLVM's choice for generated code ('noat', 806 // 'nomacro' and 'noreorder'). 807 // In order to maintain compatibility with inline assembly code which depends 808 // on GCC's assembler options being used, we have to switch to those options 809 // for the duration of the inline assembly block and then switch back. 810 TS.emitDirectiveSetPush(); 811 TS.emitDirectiveSetAt(); 812 TS.emitDirectiveSetMacro(); 813 TS.emitDirectiveSetReorder(); 814 OutStreamer->addBlankLine(); 815 } 816 817 void MipsAsmPrinter::emitInlineAsmEnd(const MCSubtargetInfo &StartInfo, 818 const MCSubtargetInfo *EndInfo) const { 819 OutStreamer->addBlankLine(); 820 getTargetStreamer().emitDirectiveSetPop(); 821 } 822 823 void MipsAsmPrinter::EmitJal(const MCSubtargetInfo &STI, MCSymbol *Symbol) { 824 MCInst I; 825 I.setOpcode(Mips::JAL); 826 I.addOperand( 827 MCOperand::createExpr(MCSymbolRefExpr::create(Symbol, OutContext))); 828 OutStreamer->emitInstruction(I, STI); 829 } 830 831 void MipsAsmPrinter::EmitInstrReg(const MCSubtargetInfo &STI, unsigned Opcode, 832 unsigned Reg) { 833 MCInst I; 834 I.setOpcode(Opcode); 835 I.addOperand(MCOperand::createReg(Reg)); 836 OutStreamer->emitInstruction(I, STI); 837 } 838 839 void MipsAsmPrinter::EmitInstrRegReg(const MCSubtargetInfo &STI, 840 unsigned Opcode, unsigned Reg1, 841 unsigned Reg2) { 842 MCInst I; 843 // 844 // Because of the current td files for Mips32, the operands for MTC1 845 // appear backwards from their normal assembly order. It's not a trivial 846 // change to fix this in the td file so we adjust for it here. 847 // 848 if (Opcode == Mips::MTC1) { 849 unsigned Temp = Reg1; 850 Reg1 = Reg2; 851 Reg2 = Temp; 852 } 853 I.setOpcode(Opcode); 854 I.addOperand(MCOperand::createReg(Reg1)); 855 I.addOperand(MCOperand::createReg(Reg2)); 856 OutStreamer->emitInstruction(I, STI); 857 } 858 859 void MipsAsmPrinter::EmitInstrRegRegReg(const MCSubtargetInfo &STI, 860 unsigned Opcode, unsigned Reg1, 861 unsigned Reg2, unsigned Reg3) { 862 MCInst I; 863 I.setOpcode(Opcode); 864 I.addOperand(MCOperand::createReg(Reg1)); 865 I.addOperand(MCOperand::createReg(Reg2)); 866 I.addOperand(MCOperand::createReg(Reg3)); 867 OutStreamer->emitInstruction(I, STI); 868 } 869 870 void MipsAsmPrinter::EmitMovFPIntPair(const MCSubtargetInfo &STI, 871 unsigned MovOpc, unsigned Reg1, 872 unsigned Reg2, unsigned FPReg1, 873 unsigned FPReg2, bool LE) { 874 if (!LE) { 875 unsigned temp = Reg1; 876 Reg1 = Reg2; 877 Reg2 = temp; 878 } 879 EmitInstrRegReg(STI, MovOpc, Reg1, FPReg1); 880 EmitInstrRegReg(STI, MovOpc, Reg2, FPReg2); 881 } 882 883 void MipsAsmPrinter::EmitSwapFPIntParams(const MCSubtargetInfo &STI, 884 Mips16HardFloatInfo::FPParamVariant PV, 885 bool LE, bool ToFP) { 886 using namespace Mips16HardFloatInfo; 887 888 unsigned MovOpc = ToFP ? Mips::MTC1 : Mips::MFC1; 889 switch (PV) { 890 case FSig: 891 EmitInstrRegReg(STI, MovOpc, Mips::A0, Mips::F12); 892 break; 893 case FFSig: 894 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F14, LE); 895 break; 896 case FDSig: 897 EmitInstrRegReg(STI, MovOpc, Mips::A0, Mips::F12); 898 EmitMovFPIntPair(STI, MovOpc, Mips::A2, Mips::A3, Mips::F14, Mips::F15, LE); 899 break; 900 case DSig: 901 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE); 902 break; 903 case DDSig: 904 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE); 905 EmitMovFPIntPair(STI, MovOpc, Mips::A2, Mips::A3, Mips::F14, Mips::F15, LE); 906 break; 907 case DFSig: 908 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE); 909 EmitInstrRegReg(STI, MovOpc, Mips::A2, Mips::F14); 910 break; 911 case NoSig: 912 return; 913 } 914 } 915 916 void MipsAsmPrinter::EmitSwapFPIntRetval( 917 const MCSubtargetInfo &STI, Mips16HardFloatInfo::FPReturnVariant RV, 918 bool LE) { 919 using namespace Mips16HardFloatInfo; 920 921 unsigned MovOpc = Mips::MFC1; 922 switch (RV) { 923 case FRet: 924 EmitInstrRegReg(STI, MovOpc, Mips::V0, Mips::F0); 925 break; 926 case DRet: 927 EmitMovFPIntPair(STI, MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE); 928 break; 929 case CFRet: 930 EmitMovFPIntPair(STI, MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE); 931 break; 932 case CDRet: 933 EmitMovFPIntPair(STI, MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE); 934 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F2, Mips::F3, LE); 935 break; 936 case NoFPRet: 937 break; 938 } 939 } 940 941 void MipsAsmPrinter::EmitFPCallStub( 942 const char *Symbol, const Mips16HardFloatInfo::FuncSignature *Signature) { 943 using namespace Mips16HardFloatInfo; 944 945 MCSymbol *MSymbol = OutContext.getOrCreateSymbol(StringRef(Symbol)); 946 bool LE = getDataLayout().isLittleEndian(); 947 // Construct a local MCSubtargetInfo here. 948 // This is because the MachineFunction won't exist (but have not yet been 949 // freed) and since we're at the global level we can use the default 950 // constructed subtarget. 951 std::unique_ptr<MCSubtargetInfo> STI(TM.getTarget().createMCSubtargetInfo( 952 TM.getTargetTriple().str(), TM.getTargetCPU(), 953 TM.getTargetFeatureString())); 954 955 // 956 // .global xxxx 957 // 958 OutStreamer->emitSymbolAttribute(MSymbol, MCSA_Global); 959 const char *RetType; 960 // 961 // make the comment field identifying the return and parameter 962 // types of the floating point stub 963 // # Stub function to call rettype xxxx (params) 964 // 965 switch (Signature->RetSig) { 966 case FRet: 967 RetType = "float"; 968 break; 969 case DRet: 970 RetType = "double"; 971 break; 972 case CFRet: 973 RetType = "complex"; 974 break; 975 case CDRet: 976 RetType = "double complex"; 977 break; 978 case NoFPRet: 979 RetType = ""; 980 break; 981 } 982 const char *Parms; 983 switch (Signature->ParamSig) { 984 case FSig: 985 Parms = "float"; 986 break; 987 case FFSig: 988 Parms = "float, float"; 989 break; 990 case FDSig: 991 Parms = "float, double"; 992 break; 993 case DSig: 994 Parms = "double"; 995 break; 996 case DDSig: 997 Parms = "double, double"; 998 break; 999 case DFSig: 1000 Parms = "double, float"; 1001 break; 1002 case NoSig: 1003 Parms = ""; 1004 break; 1005 } 1006 OutStreamer->AddComment("\t# Stub function to call " + Twine(RetType) + " " + 1007 Twine(Symbol) + " (" + Twine(Parms) + ")"); 1008 // 1009 // probably not necessary but we save and restore the current section state 1010 // 1011 OutStreamer->pushSection(); 1012 // 1013 // .section mips16.call.fpxxxx,"ax",@progbits 1014 // 1015 MCSectionELF *M = OutContext.getELFSection( 1016 ".mips16.call.fp." + std::string(Symbol), ELF::SHT_PROGBITS, 1017 ELF::SHF_ALLOC | ELF::SHF_EXECINSTR); 1018 OutStreamer->switchSection(M); 1019 // 1020 // .align 2 1021 // 1022 OutStreamer->emitValueToAlignment(Align(4)); 1023 MipsTargetStreamer &TS = getTargetStreamer(); 1024 // 1025 // .set nomips16 1026 // .set nomicromips 1027 // 1028 TS.emitDirectiveSetNoMips16(); 1029 TS.emitDirectiveSetNoMicroMips(); 1030 // 1031 // .ent __call_stub_fp_xxxx 1032 // .type __call_stub_fp_xxxx,@function 1033 // __call_stub_fp_xxxx: 1034 // 1035 std::string x = "__call_stub_fp_" + std::string(Symbol); 1036 MCSymbolELF *Stub = 1037 cast<MCSymbolELF>(OutContext.getOrCreateSymbol(StringRef(x))); 1038 TS.emitDirectiveEnt(*Stub); 1039 MCSymbol *MType = 1040 OutContext.getOrCreateSymbol("__call_stub_fp_" + Twine(Symbol)); 1041 OutStreamer->emitSymbolAttribute(MType, MCSA_ELF_TypeFunction); 1042 OutStreamer->emitLabel(Stub); 1043 1044 // Only handle non-pic for now. 1045 assert(!isPositionIndependent() && 1046 "should not be here if we are compiling pic"); 1047 TS.emitDirectiveSetReorder(); 1048 // 1049 // We need to add a MipsMCExpr class to MCTargetDesc to fully implement 1050 // stubs without raw text but this current patch is for compiler generated 1051 // functions and they all return some value. 1052 // The calling sequence for non pic is different in that case and we need 1053 // to implement %lo and %hi in order to handle the case of no return value 1054 // See the corresponding method in Mips16HardFloat for details. 1055 // 1056 // mov the return address to S2. 1057 // we have no stack space to store it and we are about to make another call. 1058 // We need to make sure that the enclosing function knows to save S2 1059 // This should have already been handled. 1060 // 1061 // Mov $18, $31 1062 1063 EmitInstrRegRegReg(*STI, Mips::OR, Mips::S2, Mips::RA, Mips::ZERO); 1064 1065 EmitSwapFPIntParams(*STI, Signature->ParamSig, LE, true); 1066 1067 // Jal xxxx 1068 // 1069 EmitJal(*STI, MSymbol); 1070 1071 // fix return values 1072 EmitSwapFPIntRetval(*STI, Signature->RetSig, LE); 1073 // 1074 // do the return 1075 // if (Signature->RetSig == NoFPRet) 1076 // llvm_unreachable("should not be any stubs here with no return value"); 1077 // else 1078 EmitInstrReg(*STI, Mips::JR, Mips::S2); 1079 1080 MCSymbol *Tmp = OutContext.createTempSymbol(); 1081 OutStreamer->emitLabel(Tmp); 1082 const MCSymbolRefExpr *E = MCSymbolRefExpr::create(Stub, OutContext); 1083 const MCSymbolRefExpr *T = MCSymbolRefExpr::create(Tmp, OutContext); 1084 const MCExpr *T_min_E = MCBinaryExpr::createSub(T, E, OutContext); 1085 OutStreamer->emitELFSize(Stub, T_min_E); 1086 TS.emitDirectiveEnd(x); 1087 OutStreamer->popSection(); 1088 } 1089 1090 void MipsAsmPrinter::emitEndOfAsmFile(Module &M) { 1091 // Emit needed stubs 1092 // 1093 for (std::map< 1094 const char *, 1095 const Mips16HardFloatInfo::FuncSignature *>::const_iterator 1096 it = StubsNeeded.begin(); 1097 it != StubsNeeded.end(); ++it) { 1098 const char *Symbol = it->first; 1099 const Mips16HardFloatInfo::FuncSignature *Signature = it->second; 1100 EmitFPCallStub(Symbol, Signature); 1101 } 1102 // return to the text section 1103 OutStreamer->switchSection(OutContext.getObjectFileInfo()->getTextSection()); 1104 } 1105 1106 void MipsAsmPrinter::EmitSled(const MachineInstr &MI, SledKind Kind) { 1107 const uint8_t NoopsInSledCount = Subtarget->isGP64bit() ? 15 : 11; 1108 // For mips32 we want to emit the following pattern: 1109 // 1110 // .Lxray_sled_N: 1111 // ALIGN 1112 // B .tmpN 1113 // 11 NOP instructions (44 bytes) 1114 // ADDIU T9, T9, 52 1115 // .tmpN 1116 // 1117 // We need the 44 bytes (11 instructions) because at runtime, we'd 1118 // be patching over the full 48 bytes (12 instructions) with the following 1119 // pattern: 1120 // 1121 // ADDIU SP, SP, -8 1122 // NOP 1123 // SW RA, 4(SP) 1124 // SW T9, 0(SP) 1125 // LUI T9, %hi(__xray_FunctionEntry/Exit) 1126 // ORI T9, T9, %lo(__xray_FunctionEntry/Exit) 1127 // LUI T0, %hi(function_id) 1128 // JALR T9 1129 // ORI T0, T0, %lo(function_id) 1130 // LW T9, 0(SP) 1131 // LW RA, 4(SP) 1132 // ADDIU SP, SP, 8 1133 // 1134 // We add 52 bytes to t9 because we want to adjust the function pointer to 1135 // the actual start of function i.e. the address just after the noop sled. 1136 // We do this because gp displacement relocation is emitted at the start of 1137 // of the function i.e after the nop sled and to correctly calculate the 1138 // global offset table address, t9 must hold the address of the instruction 1139 // containing the gp displacement relocation. 1140 // FIXME: Is this correct for the static relocation model? 1141 // 1142 // For mips64 we want to emit the following pattern: 1143 // 1144 // .Lxray_sled_N: 1145 // ALIGN 1146 // B .tmpN 1147 // 15 NOP instructions (60 bytes) 1148 // .tmpN 1149 // 1150 // We need the 60 bytes (15 instructions) because at runtime, we'd 1151 // be patching over the full 64 bytes (16 instructions) with the following 1152 // pattern: 1153 // 1154 // DADDIU SP, SP, -16 1155 // NOP 1156 // SD RA, 8(SP) 1157 // SD T9, 0(SP) 1158 // LUI T9, %highest(__xray_FunctionEntry/Exit) 1159 // ORI T9, T9, %higher(__xray_FunctionEntry/Exit) 1160 // DSLL T9, T9, 16 1161 // ORI T9, T9, %hi(__xray_FunctionEntry/Exit) 1162 // DSLL T9, T9, 16 1163 // ORI T9, T9, %lo(__xray_FunctionEntry/Exit) 1164 // LUI T0, %hi(function_id) 1165 // JALR T9 1166 // ADDIU T0, T0, %lo(function_id) 1167 // LD T9, 0(SP) 1168 // LD RA, 8(SP) 1169 // DADDIU SP, SP, 16 1170 // 1171 OutStreamer->emitCodeAlignment(Align(4), &getSubtargetInfo()); 1172 auto CurSled = OutContext.createTempSymbol("xray_sled_", true); 1173 OutStreamer->emitLabel(CurSled); 1174 auto Target = OutContext.createTempSymbol(); 1175 1176 // Emit "B .tmpN" instruction, which jumps over the nop sled to the actual 1177 // start of function 1178 const MCExpr *TargetExpr = MCSymbolRefExpr::create( 1179 Target, MCSymbolRefExpr::VariantKind::VK_None, OutContext); 1180 EmitToStreamer(*OutStreamer, MCInstBuilder(Mips::BEQ) 1181 .addReg(Mips::ZERO) 1182 .addReg(Mips::ZERO) 1183 .addExpr(TargetExpr)); 1184 1185 for (int8_t I = 0; I < NoopsInSledCount; I++) 1186 EmitToStreamer(*OutStreamer, MCInstBuilder(Mips::SLL) 1187 .addReg(Mips::ZERO) 1188 .addReg(Mips::ZERO) 1189 .addImm(0)); 1190 1191 OutStreamer->emitLabel(Target); 1192 1193 if (!Subtarget->isGP64bit()) { 1194 EmitToStreamer(*OutStreamer, 1195 MCInstBuilder(Mips::ADDiu) 1196 .addReg(Mips::T9) 1197 .addReg(Mips::T9) 1198 .addImm(0x34)); 1199 } 1200 1201 recordSled(CurSled, MI, Kind, 2); 1202 } 1203 1204 void MipsAsmPrinter::LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI) { 1205 EmitSled(MI, SledKind::FUNCTION_ENTER); 1206 } 1207 1208 void MipsAsmPrinter::LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI) { 1209 EmitSled(MI, SledKind::FUNCTION_EXIT); 1210 } 1211 1212 void MipsAsmPrinter::LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI) { 1213 EmitSled(MI, SledKind::TAIL_CALL); 1214 } 1215 1216 void MipsAsmPrinter::PrintDebugValueComment(const MachineInstr *MI, 1217 raw_ostream &OS) { 1218 // TODO: implement 1219 } 1220 1221 // Emit .dtprelword or .dtpreldword directive 1222 // and value for debug thread local expression. 1223 void MipsAsmPrinter::emitDebugValue(const MCExpr *Value, unsigned Size) const { 1224 if (auto *MipsExpr = dyn_cast<MipsMCExpr>(Value)) { 1225 if (MipsExpr && MipsExpr->getKind() == MipsMCExpr::MEK_DTPREL) { 1226 switch (Size) { 1227 case 4: 1228 OutStreamer->emitDTPRel32Value(MipsExpr->getSubExpr()); 1229 break; 1230 case 8: 1231 OutStreamer->emitDTPRel64Value(MipsExpr->getSubExpr()); 1232 break; 1233 default: 1234 llvm_unreachable("Unexpected size of expression value."); 1235 } 1236 return; 1237 } 1238 } 1239 AsmPrinter::emitDebugValue(Value, Size); 1240 } 1241 1242 // Align all targets of indirect branches on bundle size. Used only if target 1243 // is NaCl. 1244 void MipsAsmPrinter::NaClAlignIndirectJumpTargets(MachineFunction &MF) { 1245 // Align all blocks that are jumped to through jump table. 1246 if (MachineJumpTableInfo *JtInfo = MF.getJumpTableInfo()) { 1247 const std::vector<MachineJumpTableEntry> &JT = JtInfo->getJumpTables(); 1248 for (const auto &I : JT) { 1249 const std::vector<MachineBasicBlock *> &MBBs = I.MBBs; 1250 1251 for (MachineBasicBlock *MBB : MBBs) 1252 MBB->setAlignment(MIPS_NACL_BUNDLE_ALIGN); 1253 } 1254 } 1255 1256 // If basic block address is taken, block can be target of indirect branch. 1257 for (auto &MBB : MF) { 1258 if (MBB.hasAddressTaken()) 1259 MBB.setAlignment(MIPS_NACL_BUNDLE_ALIGN); 1260 } 1261 } 1262 1263 bool MipsAsmPrinter::isLongBranchPseudo(int Opcode) const { 1264 return (Opcode == Mips::LONG_BRANCH_LUi 1265 || Opcode == Mips::LONG_BRANCH_LUi2Op 1266 || Opcode == Mips::LONG_BRANCH_LUi2Op_64 1267 || Opcode == Mips::LONG_BRANCH_ADDiu 1268 || Opcode == Mips::LONG_BRANCH_ADDiu2Op 1269 || Opcode == Mips::LONG_BRANCH_DADDiu 1270 || Opcode == Mips::LONG_BRANCH_DADDiu2Op); 1271 } 1272 1273 // Force static initialization. 1274 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsAsmPrinter() { 1275 RegisterAsmPrinter<MipsAsmPrinter> X(getTheMipsTarget()); 1276 RegisterAsmPrinter<MipsAsmPrinter> Y(getTheMipselTarget()); 1277 RegisterAsmPrinter<MipsAsmPrinter> A(getTheMips64Target()); 1278 RegisterAsmPrinter<MipsAsmPrinter> B(getTheMips64elTarget()); 1279 } 1280