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 StubsNeeded.insert(I); 86 MCP = MF.getConstantPool(); 87 88 // In NaCl, all indirect jump targets must be aligned to bundle size. 89 if (Subtarget->isTargetNaCl()) 90 NaClAlignIndirectJumpTargets(MF); 91 92 AsmPrinter::runOnMachineFunction(MF); 93 94 emitXRayTable(); 95 96 return true; 97 } 98 99 bool MipsAsmPrinter::lowerOperand(const MachineOperand &MO, MCOperand &MCOp) { 100 MCOp = MCInstLowering.LowerOperand(MO); 101 return MCOp.isValid(); 102 } 103 104 #include "MipsGenMCPseudoLowering.inc" 105 106 // Lower PseudoReturn/PseudoIndirectBranch/PseudoIndirectBranch64 to JR, JR_MM, 107 // JALR, or JALR64 as appropriate for the target. 108 void MipsAsmPrinter::emitPseudoIndirectBranch(MCStreamer &OutStreamer, 109 const MachineInstr *MI) { 110 bool HasLinkReg = false; 111 bool InMicroMipsMode = Subtarget->inMicroMipsMode(); 112 MCInst TmpInst0; 113 114 if (Subtarget->hasMips64r6()) { 115 // MIPS64r6 should use (JALR64 ZERO_64, $rs) 116 TmpInst0.setOpcode(Mips::JALR64); 117 HasLinkReg = true; 118 } else if (Subtarget->hasMips32r6()) { 119 // MIPS32r6 should use (JALR ZERO, $rs) 120 if (InMicroMipsMode) 121 TmpInst0.setOpcode(Mips::JRC16_MMR6); 122 else { 123 TmpInst0.setOpcode(Mips::JALR); 124 HasLinkReg = true; 125 } 126 } else if (Subtarget->inMicroMipsMode()) 127 // microMIPS should use (JR_MM $rs) 128 TmpInst0.setOpcode(Mips::JR_MM); 129 else { 130 // Everything else should use (JR $rs) 131 TmpInst0.setOpcode(Mips::JR); 132 } 133 134 MCOperand MCOp; 135 136 if (HasLinkReg) { 137 unsigned ZeroReg = Subtarget->isGP64bit() ? Mips::ZERO_64 : Mips::ZERO; 138 TmpInst0.addOperand(MCOperand::createReg(ZeroReg)); 139 } 140 141 lowerOperand(MI->getOperand(0), MCOp); 142 TmpInst0.addOperand(MCOp); 143 144 EmitToStreamer(OutStreamer, TmpInst0); 145 } 146 147 // If there is an MO_JALR operand, insert: 148 // 149 // .reloc tmplabel, R_{MICRO}MIPS_JALR, symbol 150 // tmplabel: 151 // 152 // This is an optimization hint for the linker which may then replace 153 // an indirect call with a direct branch. 154 static void emitDirectiveRelocJalr(const MachineInstr &MI, 155 MCContext &OutContext, 156 TargetMachine &TM, 157 MCStreamer &OutStreamer, 158 const MipsSubtarget &Subtarget) { 159 for (const MachineOperand &MO : 160 llvm::drop_begin(MI.operands(), MI.getDesc().getNumOperands())) { 161 if (MO.isMCSymbol() && (MO.getTargetFlags() & MipsII::MO_JALR)) { 162 MCSymbol *Callee = MO.getMCSymbol(); 163 if (Callee && !Callee->getName().empty()) { 164 MCSymbol *OffsetLabel = OutContext.createTempSymbol(); 165 const MCExpr *OffsetExpr = 166 MCSymbolRefExpr::create(OffsetLabel, OutContext); 167 const MCExpr *CaleeExpr = 168 MCSymbolRefExpr::create(Callee, OutContext); 169 OutStreamer.emitRelocDirective( 170 *OffsetExpr, 171 Subtarget.inMicroMipsMode() ? "R_MICROMIPS_JALR" : "R_MIPS_JALR", 172 CaleeExpr, SMLoc(), *TM.getMCSubtargetInfo()); 173 OutStreamer.emitLabel(OffsetLabel); 174 return; 175 } 176 } 177 } 178 } 179 180 void MipsAsmPrinter::emitInstruction(const MachineInstr *MI) { 181 // FIXME: Enable feature predicate checks once all the test pass. 182 // Mips_MC::verifyInstructionPredicates(MI->getOpcode(), 183 // getSubtargetInfo().getFeatureBits()); 184 185 MipsTargetStreamer &TS = getTargetStreamer(); 186 unsigned Opc = MI->getOpcode(); 187 TS.forbidModuleDirective(); 188 189 if (MI->isDebugValue()) { 190 SmallString<128> Str; 191 raw_svector_ostream OS(Str); 192 193 PrintDebugValueComment(MI, OS); 194 return; 195 } 196 if (MI->isDebugLabel()) 197 return; 198 199 // If we just ended a constant pool, mark it as such. 200 if (InConstantPool && Opc != Mips::CONSTPOOL_ENTRY) { 201 OutStreamer->emitDataRegion(MCDR_DataRegionEnd); 202 InConstantPool = false; 203 } 204 if (Opc == Mips::CONSTPOOL_ENTRY) { 205 // CONSTPOOL_ENTRY - This instruction represents a floating 206 // constant pool in the function. The first operand is the ID# 207 // for this instruction, the second is the index into the 208 // MachineConstantPool that this is, the third is the size in 209 // bytes of this constant pool entry. 210 // The required alignment is specified on the basic block holding this MI. 211 // 212 unsigned LabelId = (unsigned)MI->getOperand(0).getImm(); 213 unsigned CPIdx = (unsigned)MI->getOperand(1).getIndex(); 214 215 // If this is the first entry of the pool, mark it. 216 if (!InConstantPool) { 217 OutStreamer->emitDataRegion(MCDR_DataRegion); 218 InConstantPool = true; 219 } 220 221 OutStreamer->emitLabel(GetCPISymbol(LabelId)); 222 223 const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPIdx]; 224 if (MCPE.isMachineConstantPoolEntry()) 225 emitMachineConstantPoolValue(MCPE.Val.MachineCPVal); 226 else 227 emitGlobalConstant(MF->getDataLayout(), MCPE.Val.ConstVal); 228 return; 229 } 230 231 switch (Opc) { 232 case Mips::PATCHABLE_FUNCTION_ENTER: 233 LowerPATCHABLE_FUNCTION_ENTER(*MI); 234 return; 235 case Mips::PATCHABLE_FUNCTION_EXIT: 236 LowerPATCHABLE_FUNCTION_EXIT(*MI); 237 return; 238 case Mips::PATCHABLE_TAIL_CALL: 239 LowerPATCHABLE_TAIL_CALL(*MI); 240 return; 241 } 242 243 if (EmitJalrReloc && 244 (MI->isReturn() || MI->isCall() || MI->isIndirectBranch())) { 245 emitDirectiveRelocJalr(*MI, OutContext, TM, *OutStreamer, *Subtarget); 246 } 247 248 MachineBasicBlock::const_instr_iterator I = MI->getIterator(); 249 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 250 251 do { 252 // Do any auto-generated pseudo lowerings. 253 if (MCInst OutInst; lowerPseudoInstExpansion(&*I, OutInst)) { 254 EmitToStreamer(*OutStreamer, OutInst); 255 continue; 256 } 257 258 // Skip the BUNDLE pseudo instruction and lower the contents 259 if (I->isBundle()) 260 continue; 261 262 if (I->getOpcode() == Mips::PseudoReturn || 263 I->getOpcode() == Mips::PseudoReturn64 || 264 I->getOpcode() == Mips::PseudoIndirectBranch || 265 I->getOpcode() == Mips::PseudoIndirectBranch64 || 266 I->getOpcode() == Mips::TAILCALLREG || 267 I->getOpcode() == Mips::TAILCALLREG64) { 268 emitPseudoIndirectBranch(*OutStreamer, &*I); 269 continue; 270 } 271 272 // The inMips16Mode() test is not permanent. 273 // Some instructions are marked as pseudo right now which 274 // would make the test fail for the wrong reason but 275 // that will be fixed soon. We need this here because we are 276 // removing another test for this situation downstream in the 277 // callchain. 278 // 279 if (I->isPseudo() && !Subtarget->inMips16Mode() 280 && !isLongBranchPseudo(I->getOpcode())) 281 llvm_unreachable("Pseudo opcode found in emitInstruction()"); 282 283 MCInst TmpInst0; 284 MCInstLowering.Lower(&*I, TmpInst0); 285 EmitToStreamer(*OutStreamer, TmpInst0); 286 } while ((++I != E) && I->isInsideBundle()); // Delay slot check 287 } 288 289 //===----------------------------------------------------------------------===// 290 // 291 // Mips Asm Directives 292 // 293 // -- Frame directive "frame Stackpointer, Stacksize, RARegister" 294 // Describe the stack frame. 295 // 296 // -- Mask directives "(f)mask bitmask, offset" 297 // Tells the assembler which registers are saved and where. 298 // bitmask - contain a little endian bitset indicating which registers are 299 // saved on function prologue (e.g. with a 0x80000000 mask, the 300 // assembler knows the register 31 (RA) is saved at prologue. 301 // offset - the position before stack pointer subtraction indicating where 302 // the first saved register on prologue is located. (e.g. with a 303 // 304 // Consider the following function prologue: 305 // 306 // .frame $fp,48,$ra 307 // .mask 0xc0000000,-8 308 // addiu $sp, $sp, -48 309 // sw $ra, 40($sp) 310 // sw $fp, 36($sp) 311 // 312 // With a 0xc0000000 mask, the assembler knows the register 31 (RA) and 313 // 30 (FP) are saved at prologue. As the save order on prologue is from 314 // left to right, RA is saved first. A -8 offset means that after the 315 // stack pointer subtration, the first register in the mask (RA) will be 316 // saved at address 48-8=40. 317 // 318 //===----------------------------------------------------------------------===// 319 320 //===----------------------------------------------------------------------===// 321 // Mask directives 322 //===----------------------------------------------------------------------===// 323 324 // Create a bitmask with all callee saved registers for CPU or Floating Point 325 // registers. For CPU registers consider RA, GP and FP for saving if necessary. 326 void MipsAsmPrinter::printSavedRegsBitmask() { 327 // CPU and FPU Saved Registers Bitmasks 328 unsigned CPUBitmask = 0, FPUBitmask = 0; 329 int CPUTopSavedRegOff, FPUTopSavedRegOff; 330 331 // Set the CPU and FPU Bitmasks 332 const MachineFrameInfo &MFI = MF->getFrameInfo(); 333 const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); 334 const std::vector<CalleeSavedInfo> &CSI = MFI.getCalleeSavedInfo(); 335 // size of stack area to which FP callee-saved regs are saved. 336 unsigned CPURegSize = TRI->getRegSizeInBits(Mips::GPR32RegClass) / 8; 337 unsigned FGR32RegSize = TRI->getRegSizeInBits(Mips::FGR32RegClass) / 8; 338 unsigned AFGR64RegSize = TRI->getRegSizeInBits(Mips::AFGR64RegClass) / 8; 339 bool HasAFGR64Reg = false; 340 unsigned CSFPRegsSize = 0; 341 342 for (const auto &I : CSI) { 343 Register Reg = I.getReg(); 344 unsigned RegNum = TRI->getEncodingValue(Reg); 345 346 // If it's a floating point register, set the FPU Bitmask. 347 // If it's a general purpose register, set the CPU Bitmask. 348 if (Mips::FGR32RegClass.contains(Reg)) { 349 FPUBitmask |= (1 << RegNum); 350 CSFPRegsSize += FGR32RegSize; 351 } else if (Mips::AFGR64RegClass.contains(Reg)) { 352 FPUBitmask |= (3 << RegNum); 353 CSFPRegsSize += AFGR64RegSize; 354 HasAFGR64Reg = true; 355 } else if (Mips::GPR32RegClass.contains(Reg)) 356 CPUBitmask |= (1 << RegNum); 357 } 358 359 // FP Regs are saved right below where the virtual frame pointer points to. 360 FPUTopSavedRegOff = FPUBitmask ? 361 (HasAFGR64Reg ? -AFGR64RegSize : -FGR32RegSize) : 0; 362 363 // CPU Regs are saved below FP Regs. 364 CPUTopSavedRegOff = CPUBitmask ? -CSFPRegsSize - CPURegSize : 0; 365 366 MipsTargetStreamer &TS = getTargetStreamer(); 367 // Print CPUBitmask 368 TS.emitMask(CPUBitmask, CPUTopSavedRegOff); 369 370 // Print FPUBitmask 371 TS.emitFMask(FPUBitmask, FPUTopSavedRegOff); 372 } 373 374 //===----------------------------------------------------------------------===// 375 // Frame and Set directives 376 //===----------------------------------------------------------------------===// 377 378 /// Frame Directive 379 void MipsAsmPrinter::emitFrameDirective() { 380 const TargetRegisterInfo &RI = *MF->getSubtarget().getRegisterInfo(); 381 382 Register stackReg = RI.getFrameRegister(*MF); 383 unsigned returnReg = RI.getRARegister(); 384 unsigned stackSize = MF->getFrameInfo().getStackSize(); 385 386 getTargetStreamer().emitFrame(stackReg, stackSize, returnReg); 387 } 388 389 /// Emit Set directives. 390 const char *MipsAsmPrinter::getCurrentABIString() const { 391 switch (static_cast<MipsTargetMachine &>(TM).getABI().GetEnumValue()) { 392 case MipsABIInfo::ABI::O32: return "abi32"; 393 case MipsABIInfo::ABI::N32: return "abiN32"; 394 case MipsABIInfo::ABI::N64: return "abi64"; 395 default: llvm_unreachable("Unknown Mips ABI"); 396 } 397 } 398 399 void MipsAsmPrinter::emitFunctionEntryLabel() { 400 MipsTargetStreamer &TS = getTargetStreamer(); 401 402 // NaCl sandboxing requires that indirect call instructions are masked. 403 // This means that function entry points should be bundle-aligned. 404 if (Subtarget->isTargetNaCl()) 405 emitAlignment(std::max(MF->getAlignment(), MIPS_NACL_BUNDLE_ALIGN)); 406 407 if (Subtarget->inMicroMipsMode()) { 408 TS.emitDirectiveSetMicroMips(); 409 TS.setUsesMicroMips(); 410 TS.updateABIInfo(*Subtarget); 411 } else 412 TS.emitDirectiveSetNoMicroMips(); 413 414 if (Subtarget->inMips16Mode()) 415 TS.emitDirectiveSetMips16(); 416 else 417 TS.emitDirectiveSetNoMips16(); 418 419 TS.emitDirectiveEnt(*CurrentFnSym); 420 OutStreamer->emitLabel(CurrentFnSym); 421 } 422 423 /// EmitFunctionBodyStart - Targets can override this to emit stuff before 424 /// the first basic block in the function. 425 void MipsAsmPrinter::emitFunctionBodyStart() { 426 MipsTargetStreamer &TS = getTargetStreamer(); 427 428 MCInstLowering.Initialize(&MF->getContext()); 429 430 bool IsNakedFunction = MF->getFunction().hasFnAttribute(Attribute::Naked); 431 if (!IsNakedFunction) 432 emitFrameDirective(); 433 434 if (!IsNakedFunction) 435 printSavedRegsBitmask(); 436 437 if (!Subtarget->inMips16Mode()) { 438 TS.emitDirectiveSetNoReorder(); 439 TS.emitDirectiveSetNoMacro(); 440 TS.emitDirectiveSetNoAt(); 441 } 442 } 443 444 /// EmitFunctionBodyEnd - Targets can override this to emit stuff after 445 /// the last basic block in the function. 446 void MipsAsmPrinter::emitFunctionBodyEnd() { 447 MipsTargetStreamer &TS = getTargetStreamer(); 448 449 // There are instruction for this macros, but they must 450 // always be at the function end, and we can't emit and 451 // break with BB logic. 452 if (!Subtarget->inMips16Mode()) { 453 TS.emitDirectiveSetAt(); 454 TS.emitDirectiveSetMacro(); 455 TS.emitDirectiveSetReorder(); 456 } 457 TS.emitDirectiveEnd(CurrentFnSym->getName()); 458 // Make sure to terminate any constant pools that were at the end 459 // of the function. 460 if (!InConstantPool) 461 return; 462 InConstantPool = false; 463 OutStreamer->emitDataRegion(MCDR_DataRegionEnd); 464 } 465 466 void MipsAsmPrinter::emitBasicBlockEnd(const MachineBasicBlock &MBB) { 467 AsmPrinter::emitBasicBlockEnd(MBB); 468 MipsTargetStreamer &TS = getTargetStreamer(); 469 if (MBB.empty()) 470 TS.emitDirectiveInsn(); 471 } 472 473 // Print out an operand for an inline asm expression. 474 bool MipsAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum, 475 const char *ExtraCode, raw_ostream &O) { 476 // Does this asm operand have a single letter operand modifier? 477 if (ExtraCode && ExtraCode[0]) { 478 if (ExtraCode[1] != 0) return true; // Unknown modifier. 479 480 const MachineOperand &MO = MI->getOperand(OpNum); 481 switch (ExtraCode[0]) { 482 default: 483 // See if this is a generic print operand 484 return AsmPrinter::PrintAsmOperand(MI, OpNum, ExtraCode, O); 485 case 'X': // hex const int 486 if (!MO.isImm()) 487 return true; 488 O << "0x" << Twine::utohexstr(MO.getImm()); 489 return false; 490 case 'x': // hex const int (low 16 bits) 491 if (!MO.isImm()) 492 return true; 493 O << "0x" << Twine::utohexstr(MO.getImm() & 0xffff); 494 return false; 495 case 'd': // decimal const int 496 if (!MO.isImm()) 497 return true; 498 O << MO.getImm(); 499 return false; 500 case 'm': // decimal const int minus 1 501 if (!MO.isImm()) 502 return true; 503 O << MO.getImm() - 1; 504 return false; 505 case 'y': // exact log2 506 if (!MO.isImm()) 507 return true; 508 if (!isPowerOf2_64(MO.getImm())) 509 return true; 510 O << Log2_64(MO.getImm()); 511 return false; 512 case 'z': 513 // $0 if zero, regular printing otherwise 514 if (MO.isImm() && MO.getImm() == 0) { 515 O << "$0"; 516 return false; 517 } 518 // If not, call printOperand as normal. 519 break; 520 case 'D': // Second part of a double word register operand 521 case 'L': // Low order register of a double word register operand 522 case 'M': // High order register of a double word register operand 523 { 524 if (OpNum == 0) 525 return true; 526 const MachineOperand &FlagsOP = MI->getOperand(OpNum - 1); 527 if (!FlagsOP.isImm()) 528 return true; 529 const InlineAsm::Flag Flags(FlagsOP.getImm()); 530 const unsigned NumVals = Flags.getNumOperandRegisters(); 531 // Number of registers represented by this operand. We are looking 532 // for 2 for 32 bit mode and 1 for 64 bit mode. 533 if (NumVals != 2) { 534 if (Subtarget->isGP64bit() && NumVals == 1 && MO.isReg()) { 535 Register Reg = MO.getReg(); 536 O << '$' << MipsInstPrinter::getRegisterName(Reg); 537 return false; 538 } 539 return true; 540 } 541 542 unsigned RegOp = OpNum; 543 if (!Subtarget->isGP64bit()){ 544 // Endianness reverses which register holds the high or low value 545 // between M and L. 546 switch(ExtraCode[0]) { 547 case 'M': 548 RegOp = (Subtarget->isLittle()) ? OpNum + 1 : OpNum; 549 break; 550 case 'L': 551 RegOp = (Subtarget->isLittle()) ? OpNum : OpNum + 1; 552 break; 553 case 'D': // Always the second part 554 RegOp = OpNum + 1; 555 } 556 if (RegOp >= MI->getNumOperands()) 557 return true; 558 const MachineOperand &MO = MI->getOperand(RegOp); 559 if (!MO.isReg()) 560 return true; 561 Register Reg = MO.getReg(); 562 O << '$' << MipsInstPrinter::getRegisterName(Reg); 563 return false; 564 } 565 break; 566 } 567 case 'w': { 568 MCRegister w = getMSARegFromFReg(MO.getReg()); 569 if (w != Mips::NoRegister) { 570 O << '$' << MipsInstPrinter::getRegisterName(w); 571 return false; 572 } 573 break; 574 } 575 } 576 } 577 578 printOperand(MI, OpNum, O); 579 return false; 580 } 581 582 bool MipsAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, 583 unsigned OpNum, 584 const char *ExtraCode, 585 raw_ostream &O) { 586 assert(OpNum + 1 < MI->getNumOperands() && "Insufficient operands"); 587 const MachineOperand &BaseMO = MI->getOperand(OpNum); 588 const MachineOperand &OffsetMO = MI->getOperand(OpNum + 1); 589 assert(BaseMO.isReg() && 590 "Unexpected base pointer for inline asm memory operand."); 591 assert(OffsetMO.isImm() && 592 "Unexpected offset for inline asm memory operand."); 593 int Offset = OffsetMO.getImm(); 594 595 // Currently we are expecting either no ExtraCode or 'D','M','L'. 596 if (ExtraCode) { 597 switch (ExtraCode[0]) { 598 case 'D': 599 Offset += 4; 600 break; 601 case 'M': 602 if (Subtarget->isLittle()) 603 Offset += 4; 604 break; 605 case 'L': 606 if (!Subtarget->isLittle()) 607 Offset += 4; 608 break; 609 default: 610 return true; // Unknown modifier. 611 } 612 } 613 614 O << Offset << "($" << MipsInstPrinter::getRegisterName(BaseMO.getReg()) 615 << ")"; 616 617 return false; 618 } 619 620 void MipsAsmPrinter::printOperand(const MachineInstr *MI, int opNum, 621 raw_ostream &O) { 622 const MachineOperand &MO = MI->getOperand(opNum); 623 bool closeP = false; 624 625 if (MO.getTargetFlags()) 626 closeP = true; 627 628 switch(MO.getTargetFlags()) { 629 case MipsII::MO_GPREL: O << "%gp_rel("; break; 630 case MipsII::MO_GOT_CALL: O << "%call16("; break; 631 case MipsII::MO_GOT: O << "%got("; break; 632 case MipsII::MO_ABS_HI: O << "%hi("; break; 633 case MipsII::MO_ABS_LO: O << "%lo("; break; 634 case MipsII::MO_HIGHER: O << "%higher("; break; 635 case MipsII::MO_HIGHEST: O << "%highest(("; break; 636 case MipsII::MO_TLSGD: O << "%tlsgd("; break; 637 case MipsII::MO_GOTTPREL: O << "%gottprel("; break; 638 case MipsII::MO_TPREL_HI: O << "%tprel_hi("; break; 639 case MipsII::MO_TPREL_LO: O << "%tprel_lo("; break; 640 case MipsII::MO_GPOFF_HI: O << "%hi(%neg(%gp_rel("; break; 641 case MipsII::MO_GPOFF_LO: O << "%lo(%neg(%gp_rel("; break; 642 case MipsII::MO_GOT_DISP: O << "%got_disp("; break; 643 case MipsII::MO_GOT_PAGE: O << "%got_page("; break; 644 case MipsII::MO_GOT_OFST: O << "%got_ofst("; break; 645 } 646 647 switch (MO.getType()) { 648 case MachineOperand::MO_Register: 649 O << '$' 650 << StringRef(MipsInstPrinter::getRegisterName(MO.getReg())).lower(); 651 break; 652 653 case MachineOperand::MO_Immediate: 654 O << MO.getImm(); 655 break; 656 657 case MachineOperand::MO_MachineBasicBlock: 658 MO.getMBB()->getSymbol()->print(O, MAI); 659 return; 660 661 case MachineOperand::MO_GlobalAddress: 662 PrintSymbolOperand(MO, O); 663 break; 664 665 case MachineOperand::MO_BlockAddress: { 666 MCSymbol *BA = GetBlockAddressSymbol(MO.getBlockAddress()); 667 O << BA->getName(); 668 break; 669 } 670 671 case MachineOperand::MO_ConstantPoolIndex: 672 O << getDataLayout().getPrivateGlobalPrefix() << "CPI" 673 << getFunctionNumber() << "_" << MO.getIndex(); 674 if (MO.getOffset()) 675 O << "+" << MO.getOffset(); 676 break; 677 678 default: 679 llvm_unreachable("<unknown operand type>"); 680 } 681 682 if (closeP) O << ")"; 683 } 684 685 void MipsAsmPrinter:: 686 printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O) { 687 // Load/Store memory operands -- imm($reg) 688 // If PIC target the target is loaded as the 689 // pattern lw $25,%call16($28) 690 691 // opNum can be invalid if instruction has reglist as operand. 692 // MemOperand is always last operand of instruction (base + offset). 693 switch (MI->getOpcode()) { 694 default: 695 break; 696 case Mips::SWM32_MM: 697 case Mips::LWM32_MM: 698 opNum = MI->getNumOperands() - 2; 699 break; 700 } 701 702 printOperand(MI, opNum+1, O); 703 O << "("; 704 printOperand(MI, opNum, O); 705 O << ")"; 706 } 707 708 void MipsAsmPrinter:: 709 printMemOperandEA(const MachineInstr *MI, int opNum, raw_ostream &O) { 710 // when using stack locations for not load/store instructions 711 // print the same way as all normal 3 operand instructions. 712 printOperand(MI, opNum, O); 713 O << ", "; 714 printOperand(MI, opNum+1, O); 715 } 716 717 void MipsAsmPrinter:: 718 printFCCOperand(const MachineInstr *MI, int opNum, raw_ostream &O, 719 const char *Modifier) { 720 const MachineOperand &MO = MI->getOperand(opNum); 721 O << Mips::MipsFCCToString((Mips::CondCode)MO.getImm()); 722 } 723 724 void MipsAsmPrinter:: 725 printRegisterList(const MachineInstr *MI, int opNum, raw_ostream &O) { 726 for (int i = opNum, e = MI->getNumOperands(); i != e; ++i) { 727 if (i != opNum) O << ", "; 728 printOperand(MI, i, O); 729 } 730 } 731 732 void MipsAsmPrinter::emitStartOfAsmFile(Module &M) { 733 const Triple &TT = TM.getTargetTriple(); 734 735 if (TT.isOSBinFormatELF()) { 736 MipsTargetStreamer &TS = getTargetStreamer(); 737 738 // MipsTargetStreamer has an initialization order problem when emitting an 739 // object file directly (see MipsTargetELFStreamer for full details). Work 740 // around it by re-initializing the PIC state here. 741 TS.setPic(OutContext.getObjectFileInfo()->isPositionIndependent()); 742 743 // Try to get target-features from the first function. 744 StringRef FS = TM.getTargetFeatureString(); 745 Module::iterator F = M.begin(); 746 if (FS.empty() && M.size() && F->hasFnAttribute("target-features")) 747 FS = F->getFnAttribute("target-features").getValueAsString(); 748 749 // Compute MIPS architecture attributes based on the default subtarget 750 // that we'd have constructed. 751 // FIXME: For ifunc related functions we could iterate over and look 752 // for a feature string that doesn't match the default one. 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, 756 std::nullopt); 757 758 bool IsABICalls = STI.isABICalls(); 759 const MipsABIInfo &ABI = MTM.getABI(); 760 if (IsABICalls) { 761 TS.emitDirectiveAbiCalls(); 762 // FIXME: This condition should be a lot more complicated that it is here. 763 // Ideally it should test for properties of the ABI and not the ABI 764 // itself. 765 // For the moment, I'm only correcting enough to make MIPS-IV work. 766 if (!isPositionIndependent() && STI.hasSym32()) 767 TS.emitDirectiveOptionPic0(); 768 } 769 770 // Tell the assembler which ABI we are using 771 std::string SectionName = std::string(".mdebug.") + getCurrentABIString(); 772 OutStreamer->switchSection( 773 OutContext.getELFSection(SectionName, ELF::SHT_PROGBITS, 0)); 774 775 // NaN: At the moment we only support: 776 // 1. .nan legacy (default) 777 // 2. .nan 2008 778 STI.isNaN2008() ? TS.emitDirectiveNaN2008() : 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 785 // accept it. We therefore emit it when it contradicts the ABI defaults 786 // (-mfpxx or -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 } 801 802 void MipsAsmPrinter::emitInlineAsmStart() const { 803 MipsTargetStreamer &TS = getTargetStreamer(); 804 805 // GCC's choice of assembler options for inline assembly code ('at', 'macro' 806 // and 'reorder') is different from LLVM's choice for generated code ('noat', 807 // 'nomacro' and 'noreorder'). 808 // In order to maintain compatibility with inline assembly code which depends 809 // on GCC's assembler options being used, we have to switch to those options 810 // for the duration of the inline assembly block and then switch back. 811 TS.emitDirectiveSetPush(); 812 TS.emitDirectiveSetAt(); 813 TS.emitDirectiveSetMacro(); 814 TS.emitDirectiveSetReorder(); 815 OutStreamer->addBlankLine(); 816 } 817 818 void MipsAsmPrinter::emitInlineAsmEnd(const MCSubtargetInfo &StartInfo, 819 const MCSubtargetInfo *EndInfo) const { 820 OutStreamer->addBlankLine(); 821 getTargetStreamer().emitDirectiveSetPop(); 822 } 823 824 void MipsAsmPrinter::EmitJal(const MCSubtargetInfo &STI, MCSymbol *Symbol) { 825 MCInst I; 826 I.setOpcode(Mips::JAL); 827 I.addOperand( 828 MCOperand::createExpr(MCSymbolRefExpr::create(Symbol, OutContext))); 829 OutStreamer->emitInstruction(I, STI); 830 } 831 832 void MipsAsmPrinter::EmitInstrReg(const MCSubtargetInfo &STI, unsigned Opcode, 833 unsigned Reg) { 834 MCInst I; 835 I.setOpcode(Opcode); 836 I.addOperand(MCOperand::createReg(Reg)); 837 OutStreamer->emitInstruction(I, STI); 838 } 839 840 void MipsAsmPrinter::EmitInstrRegReg(const MCSubtargetInfo &STI, 841 unsigned Opcode, unsigned Reg1, 842 unsigned Reg2) { 843 MCInst I; 844 // 845 // Because of the current td files for Mips32, the operands for MTC1 846 // appear backwards from their normal assembly order. It's not a trivial 847 // change to fix this in the td file so we adjust for it here. 848 // 849 if (Opcode == Mips::MTC1) { 850 unsigned Temp = Reg1; 851 Reg1 = Reg2; 852 Reg2 = Temp; 853 } 854 I.setOpcode(Opcode); 855 I.addOperand(MCOperand::createReg(Reg1)); 856 I.addOperand(MCOperand::createReg(Reg2)); 857 OutStreamer->emitInstruction(I, STI); 858 } 859 860 void MipsAsmPrinter::EmitInstrRegRegReg(const MCSubtargetInfo &STI, 861 unsigned Opcode, unsigned Reg1, 862 unsigned Reg2, unsigned Reg3) { 863 MCInst I; 864 I.setOpcode(Opcode); 865 I.addOperand(MCOperand::createReg(Reg1)); 866 I.addOperand(MCOperand::createReg(Reg2)); 867 I.addOperand(MCOperand::createReg(Reg3)); 868 OutStreamer->emitInstruction(I, STI); 869 } 870 871 void MipsAsmPrinter::EmitMovFPIntPair(const MCSubtargetInfo &STI, 872 unsigned MovOpc, unsigned Reg1, 873 unsigned Reg2, unsigned FPReg1, 874 unsigned FPReg2, bool LE) { 875 if (!LE) { 876 unsigned temp = Reg1; 877 Reg1 = Reg2; 878 Reg2 = temp; 879 } 880 EmitInstrRegReg(STI, MovOpc, Reg1, FPReg1); 881 EmitInstrRegReg(STI, MovOpc, Reg2, FPReg2); 882 } 883 884 void MipsAsmPrinter::EmitSwapFPIntParams(const MCSubtargetInfo &STI, 885 Mips16HardFloatInfo::FPParamVariant PV, 886 bool LE, bool ToFP) { 887 using namespace Mips16HardFloatInfo; 888 889 unsigned MovOpc = ToFP ? Mips::MTC1 : Mips::MFC1; 890 switch (PV) { 891 case FSig: 892 EmitInstrRegReg(STI, MovOpc, Mips::A0, Mips::F12); 893 break; 894 case FFSig: 895 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F14, LE); 896 break; 897 case FDSig: 898 EmitInstrRegReg(STI, MovOpc, Mips::A0, Mips::F12); 899 EmitMovFPIntPair(STI, MovOpc, Mips::A2, Mips::A3, Mips::F14, Mips::F15, LE); 900 break; 901 case DSig: 902 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE); 903 break; 904 case DDSig: 905 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE); 906 EmitMovFPIntPair(STI, MovOpc, Mips::A2, Mips::A3, Mips::F14, Mips::F15, LE); 907 break; 908 case DFSig: 909 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE); 910 EmitInstrRegReg(STI, MovOpc, Mips::A2, Mips::F14); 911 break; 912 case NoSig: 913 return; 914 } 915 } 916 917 void MipsAsmPrinter::EmitSwapFPIntRetval( 918 const MCSubtargetInfo &STI, Mips16HardFloatInfo::FPReturnVariant RV, 919 bool LE) { 920 using namespace Mips16HardFloatInfo; 921 922 unsigned MovOpc = Mips::MFC1; 923 switch (RV) { 924 case FRet: 925 EmitInstrRegReg(STI, MovOpc, Mips::V0, Mips::F0); 926 break; 927 case DRet: 928 EmitMovFPIntPair(STI, MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE); 929 break; 930 case CFRet: 931 EmitMovFPIntPair(STI, MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE); 932 break; 933 case CDRet: 934 EmitMovFPIntPair(STI, MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE); 935 EmitMovFPIntPair(STI, MovOpc, Mips::A0, Mips::A1, Mips::F2, Mips::F3, LE); 936 break; 937 case NoFPRet: 938 break; 939 } 940 } 941 942 void MipsAsmPrinter::EmitFPCallStub( 943 const char *Symbol, const Mips16HardFloatInfo::FuncSignature *Signature) { 944 using namespace Mips16HardFloatInfo; 945 946 MCSymbol *MSymbol = OutContext.getOrCreateSymbol(StringRef(Symbol)); 947 bool LE = getDataLayout().isLittleEndian(); 948 // Construct a local MCSubtargetInfo here. 949 // This is because the MachineFunction won't exist (but have not yet been 950 // freed) and since we're at the global level we can use the default 951 // constructed subtarget. 952 std::unique_ptr<MCSubtargetInfo> STI(TM.getTarget().createMCSubtargetInfo( 953 TM.getTargetTriple().str(), TM.getTargetCPU(), 954 TM.getTargetFeatureString())); 955 956 // 957 // .global xxxx 958 // 959 OutStreamer->emitSymbolAttribute(MSymbol, MCSA_Global); 960 const char *RetType; 961 // 962 // make the comment field identifying the return and parameter 963 // types of the floating point stub 964 // # Stub function to call rettype xxxx (params) 965 // 966 switch (Signature->RetSig) { 967 case FRet: 968 RetType = "float"; 969 break; 970 case DRet: 971 RetType = "double"; 972 break; 973 case CFRet: 974 RetType = "complex"; 975 break; 976 case CDRet: 977 RetType = "double complex"; 978 break; 979 case NoFPRet: 980 RetType = ""; 981 break; 982 } 983 const char *Parms; 984 switch (Signature->ParamSig) { 985 case FSig: 986 Parms = "float"; 987 break; 988 case FFSig: 989 Parms = "float, float"; 990 break; 991 case FDSig: 992 Parms = "float, double"; 993 break; 994 case DSig: 995 Parms = "double"; 996 break; 997 case DDSig: 998 Parms = "double, double"; 999 break; 1000 case DFSig: 1001 Parms = "double, float"; 1002 break; 1003 case NoSig: 1004 Parms = ""; 1005 break; 1006 } 1007 OutStreamer->AddComment("\t# Stub function to call " + Twine(RetType) + " " + 1008 Twine(Symbol) + " (" + Twine(Parms) + ")"); 1009 // 1010 // probably not necessary but we save and restore the current section state 1011 // 1012 OutStreamer->pushSection(); 1013 // 1014 // .section mips16.call.fpxxxx,"ax",@progbits 1015 // 1016 MCSectionELF *M = OutContext.getELFSection( 1017 ".mips16.call.fp." + std::string(Symbol), ELF::SHT_PROGBITS, 1018 ELF::SHF_ALLOC | ELF::SHF_EXECINSTR); 1019 OutStreamer->switchSection(M); 1020 // 1021 // .align 2 1022 // 1023 OutStreamer->emitValueToAlignment(Align(4)); 1024 MipsTargetStreamer &TS = getTargetStreamer(); 1025 // 1026 // .set nomips16 1027 // .set nomicromips 1028 // 1029 TS.emitDirectiveSetNoMips16(); 1030 TS.emitDirectiveSetNoMicroMips(); 1031 // 1032 // .ent __call_stub_fp_xxxx 1033 // .type __call_stub_fp_xxxx,@function 1034 // __call_stub_fp_xxxx: 1035 // 1036 std::string x = "__call_stub_fp_" + std::string(Symbol); 1037 MCSymbolELF *Stub = 1038 cast<MCSymbolELF>(OutContext.getOrCreateSymbol(StringRef(x))); 1039 TS.emitDirectiveEnt(*Stub); 1040 MCSymbol *MType = 1041 OutContext.getOrCreateSymbol("__call_stub_fp_" + Twine(Symbol)); 1042 OutStreamer->emitSymbolAttribute(MType, MCSA_ELF_TypeFunction); 1043 OutStreamer->emitLabel(Stub); 1044 1045 // Only handle non-pic for now. 1046 assert(!isPositionIndependent() && 1047 "should not be here if we are compiling pic"); 1048 TS.emitDirectiveSetReorder(); 1049 // 1050 // We need to add a MipsMCExpr class to MCTargetDesc to fully implement 1051 // stubs without raw text but this current patch is for compiler generated 1052 // functions and they all return some value. 1053 // The calling sequence for non pic is different in that case and we need 1054 // to implement %lo and %hi in order to handle the case of no return value 1055 // See the corresponding method in Mips16HardFloat for details. 1056 // 1057 // mov the return address to S2. 1058 // we have no stack space to store it and we are about to make another call. 1059 // We need to make sure that the enclosing function knows to save S2 1060 // This should have already been handled. 1061 // 1062 // Mov $18, $31 1063 1064 EmitInstrRegRegReg(*STI, Mips::OR, Mips::S2, Mips::RA, Mips::ZERO); 1065 1066 EmitSwapFPIntParams(*STI, Signature->ParamSig, LE, true); 1067 1068 // Jal xxxx 1069 // 1070 EmitJal(*STI, MSymbol); 1071 1072 // fix return values 1073 EmitSwapFPIntRetval(*STI, Signature->RetSig, LE); 1074 // 1075 // do the return 1076 // if (Signature->RetSig == NoFPRet) 1077 // llvm_unreachable("should not be any stubs here with no return value"); 1078 // else 1079 EmitInstrReg(*STI, Mips::JR, Mips::S2); 1080 1081 MCSymbol *Tmp = OutContext.createTempSymbol(); 1082 OutStreamer->emitLabel(Tmp); 1083 const MCSymbolRefExpr *E = MCSymbolRefExpr::create(Stub, OutContext); 1084 const MCSymbolRefExpr *T = MCSymbolRefExpr::create(Tmp, OutContext); 1085 const MCExpr *T_min_E = MCBinaryExpr::createSub(T, E, OutContext); 1086 OutStreamer->emitELFSize(Stub, T_min_E); 1087 TS.emitDirectiveEnd(x); 1088 OutStreamer->popSection(); 1089 } 1090 1091 void MipsAsmPrinter::emitEndOfAsmFile(Module &M) { 1092 // Emit needed stubs 1093 // 1094 for (std::map< 1095 const char *, 1096 const Mips16HardFloatInfo::FuncSignature *>::const_iterator 1097 it = StubsNeeded.begin(); 1098 it != StubsNeeded.end(); ++it) { 1099 const char *Symbol = it->first; 1100 const Mips16HardFloatInfo::FuncSignature *Signature = it->second; 1101 EmitFPCallStub(Symbol, Signature); 1102 } 1103 // return to the text section 1104 OutStreamer->switchSection(OutContext.getObjectFileInfo()->getTextSection()); 1105 } 1106 1107 void MipsAsmPrinter::EmitSled(const MachineInstr &MI, SledKind Kind) { 1108 const uint8_t NoopsInSledCount = Subtarget->isGP64bit() ? 15 : 11; 1109 // For mips32 we want to emit the following pattern: 1110 // 1111 // .Lxray_sled_N: 1112 // ALIGN 1113 // B .tmpN 1114 // 11 NOP instructions (44 bytes) 1115 // ADDIU T9, T9, 52 1116 // .tmpN 1117 // 1118 // We need the 44 bytes (11 instructions) because at runtime, we'd 1119 // be patching over the full 48 bytes (12 instructions) with the following 1120 // pattern: 1121 // 1122 // ADDIU SP, SP, -8 1123 // NOP 1124 // SW RA, 4(SP) 1125 // SW T9, 0(SP) 1126 // LUI T9, %hi(__xray_FunctionEntry/Exit) 1127 // ORI T9, T9, %lo(__xray_FunctionEntry/Exit) 1128 // LUI T0, %hi(function_id) 1129 // JALR T9 1130 // ORI T0, T0, %lo(function_id) 1131 // LW T9, 0(SP) 1132 // LW RA, 4(SP) 1133 // ADDIU SP, SP, 8 1134 // 1135 // We add 52 bytes to t9 because we want to adjust the function pointer to 1136 // the actual start of function i.e. the address just after the noop sled. 1137 // We do this because gp displacement relocation is emitted at the start of 1138 // of the function i.e after the nop sled and to correctly calculate the 1139 // global offset table address, t9 must hold the address of the instruction 1140 // containing the gp displacement relocation. 1141 // FIXME: Is this correct for the static relocation model? 1142 // 1143 // For mips64 we want to emit the following pattern: 1144 // 1145 // .Lxray_sled_N: 1146 // ALIGN 1147 // B .tmpN 1148 // 15 NOP instructions (60 bytes) 1149 // .tmpN 1150 // 1151 // We need the 60 bytes (15 instructions) because at runtime, we'd 1152 // be patching over the full 64 bytes (16 instructions) with the following 1153 // pattern: 1154 // 1155 // DADDIU SP, SP, -16 1156 // NOP 1157 // SD RA, 8(SP) 1158 // SD T9, 0(SP) 1159 // LUI T9, %highest(__xray_FunctionEntry/Exit) 1160 // ORI T9, T9, %higher(__xray_FunctionEntry/Exit) 1161 // DSLL T9, T9, 16 1162 // ORI T9, T9, %hi(__xray_FunctionEntry/Exit) 1163 // DSLL T9, T9, 16 1164 // ORI T9, T9, %lo(__xray_FunctionEntry/Exit) 1165 // LUI T0, %hi(function_id) 1166 // JALR T9 1167 // ADDIU T0, T0, %lo(function_id) 1168 // LD T9, 0(SP) 1169 // LD RA, 8(SP) 1170 // DADDIU SP, SP, 16 1171 // 1172 OutStreamer->emitCodeAlignment(Align(4), &getSubtargetInfo()); 1173 auto CurSled = OutContext.createTempSymbol("xray_sled_", true); 1174 OutStreamer->emitLabel(CurSled); 1175 auto Target = OutContext.createTempSymbol(); 1176 1177 // Emit "B .tmpN" instruction, which jumps over the nop sled to the actual 1178 // start of function 1179 const MCExpr *TargetExpr = MCSymbolRefExpr::create( 1180 Target, MCSymbolRefExpr::VariantKind::VK_None, OutContext); 1181 EmitToStreamer(*OutStreamer, MCInstBuilder(Mips::BEQ) 1182 .addReg(Mips::ZERO) 1183 .addReg(Mips::ZERO) 1184 .addExpr(TargetExpr)); 1185 1186 for (int8_t I = 0; I < NoopsInSledCount; I++) 1187 EmitToStreamer(*OutStreamer, MCInstBuilder(Mips::SLL) 1188 .addReg(Mips::ZERO) 1189 .addReg(Mips::ZERO) 1190 .addImm(0)); 1191 1192 OutStreamer->emitLabel(Target); 1193 1194 if (!Subtarget->isGP64bit()) { 1195 EmitToStreamer(*OutStreamer, 1196 MCInstBuilder(Mips::ADDiu) 1197 .addReg(Mips::T9) 1198 .addReg(Mips::T9) 1199 .addImm(0x34)); 1200 } 1201 1202 recordSled(CurSled, MI, Kind, 2); 1203 } 1204 1205 void MipsAsmPrinter::LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI) { 1206 EmitSled(MI, SledKind::FUNCTION_ENTER); 1207 } 1208 1209 void MipsAsmPrinter::LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI) { 1210 EmitSled(MI, SledKind::FUNCTION_EXIT); 1211 } 1212 1213 void MipsAsmPrinter::LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI) { 1214 EmitSled(MI, SledKind::TAIL_CALL); 1215 } 1216 1217 void MipsAsmPrinter::PrintDebugValueComment(const MachineInstr *MI, 1218 raw_ostream &OS) { 1219 // TODO: implement 1220 } 1221 1222 // Emit .dtprelword or .dtpreldword directive 1223 // and value for debug thread local expression. 1224 void MipsAsmPrinter::emitDebugValue(const MCExpr *Value, unsigned Size) const { 1225 if (auto *MipsExpr = dyn_cast<MipsMCExpr>(Value)) { 1226 if (MipsExpr && MipsExpr->getKind() == MipsMCExpr::MEK_DTPREL) { 1227 switch (Size) { 1228 case 4: 1229 OutStreamer->emitDTPRel32Value(MipsExpr->getSubExpr()); 1230 break; 1231 case 8: 1232 OutStreamer->emitDTPRel64Value(MipsExpr->getSubExpr()); 1233 break; 1234 default: 1235 llvm_unreachable("Unexpected size of expression value."); 1236 } 1237 return; 1238 } 1239 } 1240 AsmPrinter::emitDebugValue(Value, Size); 1241 } 1242 1243 // Align all targets of indirect branches on bundle size. Used only if target 1244 // is NaCl. 1245 void MipsAsmPrinter::NaClAlignIndirectJumpTargets(MachineFunction &MF) { 1246 // Align all blocks that are jumped to through jump table. 1247 if (MachineJumpTableInfo *JtInfo = MF.getJumpTableInfo()) { 1248 const std::vector<MachineJumpTableEntry> &JT = JtInfo->getJumpTables(); 1249 for (const auto &I : JT) { 1250 const std::vector<MachineBasicBlock *> &MBBs = I.MBBs; 1251 1252 for (MachineBasicBlock *MBB : MBBs) 1253 MBB->setAlignment(MIPS_NACL_BUNDLE_ALIGN); 1254 } 1255 } 1256 1257 // If basic block address is taken, block can be target of indirect branch. 1258 for (auto &MBB : MF) { 1259 if (MBB.hasAddressTaken()) 1260 MBB.setAlignment(MIPS_NACL_BUNDLE_ALIGN); 1261 } 1262 } 1263 1264 bool MipsAsmPrinter::isLongBranchPseudo(int Opcode) const { 1265 return (Opcode == Mips::LONG_BRANCH_LUi 1266 || Opcode == Mips::LONG_BRANCH_LUi2Op 1267 || Opcode == Mips::LONG_BRANCH_LUi2Op_64 1268 || Opcode == Mips::LONG_BRANCH_ADDiu 1269 || Opcode == Mips::LONG_BRANCH_ADDiu2Op 1270 || Opcode == Mips::LONG_BRANCH_DADDiu 1271 || Opcode == Mips::LONG_BRANCH_DADDiu2Op); 1272 } 1273 1274 // Force static initialization. 1275 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsAsmPrinter() { 1276 RegisterAsmPrinter<MipsAsmPrinter> X(getTheMipsTarget()); 1277 RegisterAsmPrinter<MipsAsmPrinter> Y(getTheMipselTarget()); 1278 RegisterAsmPrinter<MipsAsmPrinter> A(getTheMips64Target()); 1279 RegisterAsmPrinter<MipsAsmPrinter> B(getTheMips64elTarget()); 1280 } 1281