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1//===-- X86IntelInstPrinter.cpp - Intel assembly instruction printing -----===//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-exception6//7//===----------------------------------------------------------------------===//8//9// This file includes code for rendering MCInst instances as Intel-style10// assembly.11//12//===----------------------------------------------------------------------===//13 14#include "X86IntelInstPrinter.h"15#include "X86BaseInfo.h"16#include "X86InstComments.h"17#include "llvm/MC/MCAsmInfo.h"18#include "llvm/MC/MCExpr.h"19#include "llvm/MC/MCInst.h"20#include "llvm/MC/MCInstrAnalysis.h"21#include "llvm/MC/MCInstrDesc.h"22#include "llvm/MC/MCInstrInfo.h"23#include "llvm/MC/MCSubtargetInfo.h"24#include "llvm/Support/ErrorHandling.h"25#include <cassert>26#include <cstdint>27 28using namespace llvm;29 30#define DEBUG_TYPE "asm-printer"31 32// Include the auto-generated portion of the assembly writer.33#define PRINT_ALIAS_INSTR34#include "X86GenAsmWriter1.inc"35 36void X86IntelInstPrinter::printRegName(raw_ostream &OS, MCRegister Reg) {37  markup(OS, Markup::Register) << getRegisterName(Reg);38}39 40void X86IntelInstPrinter::printInst(const MCInst *MI, uint64_t Address,41                                    StringRef Annot, const MCSubtargetInfo &STI,42                                    raw_ostream &OS) {43  printInstFlags(MI, OS, STI);44 45  // In 16-bit mode, print data16 as data32.46  if (MI->getOpcode() == X86::DATA16_PREFIX &&47      STI.hasFeature(X86::Is16Bit)) {48    OS << "\tdata32";49  } else if (!printAliasInstr(MI, Address, OS) && !printVecCompareInstr(MI, OS))50    printInstruction(MI, Address, OS);51 52  // Next always print the annotation.53  printAnnotation(OS, Annot);54 55  // If verbose assembly is enabled, we can print some informative comments.56  if (CommentStream)57    EmitAnyX86InstComments(MI, *CommentStream, MII);58}59 60bool X86IntelInstPrinter::printVecCompareInstr(const MCInst *MI, raw_ostream &OS) {61  if (MI->getNumOperands() == 0 ||62      !MI->getOperand(MI->getNumOperands() - 1).isImm())63    return false;64 65  int64_t Imm = MI->getOperand(MI->getNumOperands() - 1).getImm();66 67  const MCInstrDesc &Desc = MII.get(MI->getOpcode());68 69  // Custom print the vector compare instructions to get the immediate70  // translated into the mnemonic.71  switch (MI->getOpcode()) {72  case X86::CMPPDrmi:     case X86::CMPPDrri:73  case X86::CMPPSrmi:     case X86::CMPPSrri:74  case X86::CMPSDrmi:     case X86::CMPSDrri:75  case X86::CMPSDrmi_Int: case X86::CMPSDrri_Int:76  case X86::CMPSSrmi:     case X86::CMPSSrri:77  case X86::CMPSSrmi_Int: case X86::CMPSSrri_Int:78    if (Imm >= 0 && Imm <= 7) {79      OS << '\t';80      printCMPMnemonic(MI, /*IsVCMP*/false, OS);81      printOperand(MI, 0, OS);82      OS << ", ";83      // Skip operand 1 as its tied to the dest.84 85      if ((Desc.TSFlags & X86II::FormMask) == X86II::MRMSrcMem) {86        if ((Desc.TSFlags & X86II::OpPrefixMask) == X86II::XS)87          printdwordmem(MI, 2, OS);88        else if ((Desc.TSFlags & X86II::OpPrefixMask) == X86II::XD)89          printqwordmem(MI, 2, OS);90        else91          printxmmwordmem(MI, 2, OS);92      } else93        printOperand(MI, 2, OS);94 95      return true;96    }97    break;98 99  case X86::VCMPPDrmi:       case X86::VCMPPDrri:100  case X86::VCMPPDYrmi:      case X86::VCMPPDYrri:101  case X86::VCMPPDZ128rmi:   case X86::VCMPPDZ128rri:102  case X86::VCMPPDZ256rmi:   case X86::VCMPPDZ256rri:103  case X86::VCMPPDZrmi:      case X86::VCMPPDZrri:104  case X86::VCMPPSrmi:       case X86::VCMPPSrri:105  case X86::VCMPPSYrmi:      case X86::VCMPPSYrri:106  case X86::VCMPPSZ128rmi:   case X86::VCMPPSZ128rri:107  case X86::VCMPPSZ256rmi:   case X86::VCMPPSZ256rri:108  case X86::VCMPPSZrmi:      case X86::VCMPPSZrri:109  case X86::VCMPSDrmi:       case X86::VCMPSDrri:110  case X86::VCMPSDZrmi:      case X86::VCMPSDZrri:111  case X86::VCMPSDrmi_Int:   case X86::VCMPSDrri_Int:112  case X86::VCMPSDZrmi_Int:  case X86::VCMPSDZrri_Int:113  case X86::VCMPSSrmi:       case X86::VCMPSSrri:114  case X86::VCMPSSZrmi:      case X86::VCMPSSZrri:115  case X86::VCMPSSrmi_Int:   case X86::VCMPSSrri_Int:116  case X86::VCMPSSZrmi_Int:  case X86::VCMPSSZrri_Int:117  case X86::VCMPPDZ128rmik:  case X86::VCMPPDZ128rrik:118  case X86::VCMPPDZ256rmik:  case X86::VCMPPDZ256rrik:119  case X86::VCMPPDZrmik:     case X86::VCMPPDZrrik:120  case X86::VCMPPSZ128rmik:  case X86::VCMPPSZ128rrik:121  case X86::VCMPPSZ256rmik:  case X86::VCMPPSZ256rrik:122  case X86::VCMPPSZrmik:     case X86::VCMPPSZrrik:123  case X86::VCMPSDZrmik_Int: case X86::VCMPSDZrrik_Int:124  case X86::VCMPSSZrmik_Int: case X86::VCMPSSZrrik_Int:125  case X86::VCMPPDZ128rmbi:  case X86::VCMPPDZ128rmbik:126  case X86::VCMPPDZ256rmbi:  case X86::VCMPPDZ256rmbik:127  case X86::VCMPPDZrmbi:     case X86::VCMPPDZrmbik:128  case X86::VCMPPSZ128rmbi:  case X86::VCMPPSZ128rmbik:129  case X86::VCMPPSZ256rmbi:  case X86::VCMPPSZ256rmbik:130  case X86::VCMPPSZrmbi:     case X86::VCMPPSZrmbik:131  case X86::VCMPPDZrrib:     case X86::VCMPPDZrribk:132  case X86::VCMPPSZrrib:     case X86::VCMPPSZrribk:133  case X86::VCMPSDZrrib_Int: case X86::VCMPSDZrribk_Int:134  case X86::VCMPSSZrrib_Int: case X86::VCMPSSZrribk_Int:135  case X86::VCMPPHZ128rmi:   case X86::VCMPPHZ128rri:136  case X86::VCMPPHZ256rmi:   case X86::VCMPPHZ256rri:137  case X86::VCMPPHZrmi:      case X86::VCMPPHZrri:138  case X86::VCMPSHZrmi:      case X86::VCMPSHZrri:139  case X86::VCMPSHZrmi_Int:  case X86::VCMPSHZrri_Int:140  case X86::VCMPPHZ128rmik:  case X86::VCMPPHZ128rrik:141  case X86::VCMPPHZ256rmik:  case X86::VCMPPHZ256rrik:142  case X86::VCMPPHZrmik:     case X86::VCMPPHZrrik:143  case X86::VCMPSHZrmik_Int: case X86::VCMPSHZrrik_Int:144  case X86::VCMPPHZ128rmbi:  case X86::VCMPPHZ128rmbik:145  case X86::VCMPPHZ256rmbi:  case X86::VCMPPHZ256rmbik:146  case X86::VCMPPHZrmbi:     case X86::VCMPPHZrmbik:147  case X86::VCMPPHZrrib:     case X86::VCMPPHZrribk:148  case X86::VCMPSHZrrib_Int: case X86::VCMPSHZrribk_Int:149  case X86::VCMPBF16Z128rmi:  case X86::VCMPBF16Z128rri:150  case X86::VCMPBF16Z256rmi:  case X86::VCMPBF16Z256rri:151  case X86::VCMPBF16Zrmi:     case X86::VCMPBF16Zrri:152  case X86::VCMPBF16Z128rmik: case X86::VCMPBF16Z128rrik:153  case X86::VCMPBF16Z256rmik: case X86::VCMPBF16Z256rrik:154  case X86::VCMPBF16Zrmik:    case X86::VCMPBF16Zrrik:155  case X86::VCMPBF16Z128rmbi: case X86::VCMPBF16Z128rmbik:156  case X86::VCMPBF16Z256rmbi: case X86::VCMPBF16Z256rmbik:157  case X86::VCMPBF16Zrmbi:    case X86::VCMPBF16Zrmbik:158    if (Imm >= 0 && Imm <= 31) {159      OS << '\t';160      printCMPMnemonic(MI, /*IsVCMP*/true, OS);161 162      unsigned CurOp = 0;163      printOperand(MI, CurOp++, OS);164 165      if (Desc.TSFlags & X86II::EVEX_K) {166        // Print mask operand.167        OS << " {";168        printOperand(MI, CurOp++, OS);169        OS << "}";170      }171      OS << ", ";172      printOperand(MI, CurOp++, OS);173      OS << ", ";174 175      if ((Desc.TSFlags & X86II::FormMask) == X86II::MRMSrcMem) {176        if (Desc.TSFlags & X86II::EVEX_B) {177          // Broadcast form.178          // Load size is word for TA map. Otherwise it is based on W-bit.179          if ((Desc.TSFlags & X86II::OpMapMask) == X86II::TA) {180            assert(!(Desc.TSFlags & X86II::REX_W) && "Unknown W-bit value!");181            printwordmem(MI, CurOp++, OS);182          } else if (Desc.TSFlags & X86II::REX_W) {183            printqwordmem(MI, CurOp++, OS);184          } else {185            printdwordmem(MI, CurOp++, OS);186          }187 188          // Print the number of elements broadcasted.189          unsigned NumElts;190          if (Desc.TSFlags & X86II::EVEX_L2)191            NumElts = (Desc.TSFlags & X86II::REX_W) ? 8 : 16;192          else if (Desc.TSFlags & X86II::VEX_L)193            NumElts = (Desc.TSFlags & X86II::REX_W) ? 4 : 8;194          else195            NumElts = (Desc.TSFlags & X86II::REX_W) ? 2 : 4;196          if ((Desc.TSFlags & X86II::OpMapMask) == X86II::TA) {197            assert(!(Desc.TSFlags & X86II::REX_W) && "Unknown W-bit value!");198            NumElts *= 2;199          }200          OS << "{1to" << NumElts << "}";201        } else {202          if ((Desc.TSFlags & X86II::OpPrefixMask) == X86II::XS) {203            if ((Desc.TSFlags & X86II::OpMapMask) == X86II::TA)204              printwordmem(MI, CurOp++, OS);205            else206              printdwordmem(MI, CurOp++, OS);207          } else if ((Desc.TSFlags & X86II::OpPrefixMask) == X86II::XD &&208                     (Desc.TSFlags & X86II::OpMapMask) != X86II::TA) {209            printqwordmem(MI, CurOp++, OS);210          } else if (Desc.TSFlags & X86II::EVEX_L2) {211            printzmmwordmem(MI, CurOp++, OS);212          } else if (Desc.TSFlags & X86II::VEX_L) {213            printymmwordmem(MI, CurOp++, OS);214          } else {215            printxmmwordmem(MI, CurOp++, OS);216          }217        }218      } else {219        printOperand(MI, CurOp++, OS);220        if (Desc.TSFlags & X86II::EVEX_B)221          OS << ", {sae}";222      }223 224      return true;225    }226    break;227 228  case X86::VPCOMBmi:  case X86::VPCOMBri:229  case X86::VPCOMDmi:  case X86::VPCOMDri:230  case X86::VPCOMQmi:  case X86::VPCOMQri:231  case X86::VPCOMUBmi: case X86::VPCOMUBri:232  case X86::VPCOMUDmi: case X86::VPCOMUDri:233  case X86::VPCOMUQmi: case X86::VPCOMUQri:234  case X86::VPCOMUWmi: case X86::VPCOMUWri:235  case X86::VPCOMWmi:  case X86::VPCOMWri:236    if (Imm >= 0 && Imm <= 7) {237      OS << '\t';238      printVPCOMMnemonic(MI, OS);239      printOperand(MI, 0, OS);240      OS << ", ";241      printOperand(MI, 1, OS);242      OS << ", ";243      if ((Desc.TSFlags & X86II::FormMask) == X86II::MRMSrcMem)244        printxmmwordmem(MI, 2, OS);245      else246        printOperand(MI, 2, OS);247      return true;248    }249    break;250 251  case X86::VPCMPBZ128rmi:   case X86::VPCMPBZ128rri:252  case X86::VPCMPBZ256rmi:   case X86::VPCMPBZ256rri:253  case X86::VPCMPBZrmi:      case X86::VPCMPBZrri:254  case X86::VPCMPDZ128rmi:   case X86::VPCMPDZ128rri:255  case X86::VPCMPDZ256rmi:   case X86::VPCMPDZ256rri:256  case X86::VPCMPDZrmi:      case X86::VPCMPDZrri:257  case X86::VPCMPQZ128rmi:   case X86::VPCMPQZ128rri:258  case X86::VPCMPQZ256rmi:   case X86::VPCMPQZ256rri:259  case X86::VPCMPQZrmi:      case X86::VPCMPQZrri:260  case X86::VPCMPUBZ128rmi:  case X86::VPCMPUBZ128rri:261  case X86::VPCMPUBZ256rmi:  case X86::VPCMPUBZ256rri:262  case X86::VPCMPUBZrmi:     case X86::VPCMPUBZrri:263  case X86::VPCMPUDZ128rmi:  case X86::VPCMPUDZ128rri:264  case X86::VPCMPUDZ256rmi:  case X86::VPCMPUDZ256rri:265  case X86::VPCMPUDZrmi:     case X86::VPCMPUDZrri:266  case X86::VPCMPUQZ128rmi:  case X86::VPCMPUQZ128rri:267  case X86::VPCMPUQZ256rmi:  case X86::VPCMPUQZ256rri:268  case X86::VPCMPUQZrmi:     case X86::VPCMPUQZrri:269  case X86::VPCMPUWZ128rmi:  case X86::VPCMPUWZ128rri:270  case X86::VPCMPUWZ256rmi:  case X86::VPCMPUWZ256rri:271  case X86::VPCMPUWZrmi:     case X86::VPCMPUWZrri:272  case X86::VPCMPWZ128rmi:   case X86::VPCMPWZ128rri:273  case X86::VPCMPWZ256rmi:   case X86::VPCMPWZ256rri:274  case X86::VPCMPWZrmi:      case X86::VPCMPWZrri:275  case X86::VPCMPBZ128rmik:  case X86::VPCMPBZ128rrik:276  case X86::VPCMPBZ256rmik:  case X86::VPCMPBZ256rrik:277  case X86::VPCMPBZrmik:     case X86::VPCMPBZrrik:278  case X86::VPCMPDZ128rmik:  case X86::VPCMPDZ128rrik:279  case X86::VPCMPDZ256rmik:  case X86::VPCMPDZ256rrik:280  case X86::VPCMPDZrmik:     case X86::VPCMPDZrrik:281  case X86::VPCMPQZ128rmik:  case X86::VPCMPQZ128rrik:282  case X86::VPCMPQZ256rmik:  case X86::VPCMPQZ256rrik:283  case X86::VPCMPQZrmik:     case X86::VPCMPQZrrik:284  case X86::VPCMPUBZ128rmik: case X86::VPCMPUBZ128rrik:285  case X86::VPCMPUBZ256rmik: case X86::VPCMPUBZ256rrik:286  case X86::VPCMPUBZrmik:    case X86::VPCMPUBZrrik:287  case X86::VPCMPUDZ128rmik: case X86::VPCMPUDZ128rrik:288  case X86::VPCMPUDZ256rmik: case X86::VPCMPUDZ256rrik:289  case X86::VPCMPUDZrmik:    case X86::VPCMPUDZrrik:290  case X86::VPCMPUQZ128rmik: case X86::VPCMPUQZ128rrik:291  case X86::VPCMPUQZ256rmik: case X86::VPCMPUQZ256rrik:292  case X86::VPCMPUQZrmik:    case X86::VPCMPUQZrrik:293  case X86::VPCMPUWZ128rmik: case X86::VPCMPUWZ128rrik:294  case X86::VPCMPUWZ256rmik: case X86::VPCMPUWZ256rrik:295  case X86::VPCMPUWZrmik:    case X86::VPCMPUWZrrik:296  case X86::VPCMPWZ128rmik:  case X86::VPCMPWZ128rrik:297  case X86::VPCMPWZ256rmik:  case X86::VPCMPWZ256rrik:298  case X86::VPCMPWZrmik:     case X86::VPCMPWZrrik:299  case X86::VPCMPDZ128rmbi:  case X86::VPCMPDZ128rmbik:300  case X86::VPCMPDZ256rmbi:  case X86::VPCMPDZ256rmbik:301  case X86::VPCMPDZrmbi:     case X86::VPCMPDZrmbik:302  case X86::VPCMPQZ128rmbi:  case X86::VPCMPQZ128rmbik:303  case X86::VPCMPQZ256rmbi:  case X86::VPCMPQZ256rmbik:304  case X86::VPCMPQZrmbi:     case X86::VPCMPQZrmbik:305  case X86::VPCMPUDZ128rmbi: case X86::VPCMPUDZ128rmbik:306  case X86::VPCMPUDZ256rmbi: case X86::VPCMPUDZ256rmbik:307  case X86::VPCMPUDZrmbi:    case X86::VPCMPUDZrmbik:308  case X86::VPCMPUQZ128rmbi: case X86::VPCMPUQZ128rmbik:309  case X86::VPCMPUQZ256rmbi: case X86::VPCMPUQZ256rmbik:310  case X86::VPCMPUQZrmbi:    case X86::VPCMPUQZrmbik:311    if ((Imm >= 0 && Imm <= 2) || (Imm >= 4 && Imm <= 6)) {312      OS << '\t';313      printVPCMPMnemonic(MI, OS);314 315      unsigned CurOp = 0;316      printOperand(MI, CurOp++, OS);317 318      if (Desc.TSFlags & X86II::EVEX_K) {319        // Print mask operand.320        OS << " {";321        printOperand(MI, CurOp++, OS);322        OS << "}";323      }324      OS << ", ";325      printOperand(MI, CurOp++, OS);326      OS << ", ";327 328      if ((Desc.TSFlags & X86II::FormMask) == X86II::MRMSrcMem) {329        if (Desc.TSFlags & X86II::EVEX_B) {330          // Broadcast form.331          // Load size is based on W-bit as only D and Q are supported.332          if (Desc.TSFlags & X86II::REX_W)333            printqwordmem(MI, CurOp++, OS);334          else335            printdwordmem(MI, CurOp++, OS);336 337          // Print the number of elements broadcasted.338          unsigned NumElts;339          if (Desc.TSFlags & X86II::EVEX_L2)340            NumElts = (Desc.TSFlags & X86II::REX_W) ? 8 : 16;341          else if (Desc.TSFlags & X86II::VEX_L)342            NumElts = (Desc.TSFlags & X86II::REX_W) ? 4 : 8;343          else344            NumElts = (Desc.TSFlags & X86II::REX_W) ? 2 : 4;345          OS << "{1to" << NumElts << "}";346        } else {347          if (Desc.TSFlags & X86II::EVEX_L2)348            printzmmwordmem(MI, CurOp++, OS);349          else if (Desc.TSFlags & X86II::VEX_L)350            printymmwordmem(MI, CurOp++, OS);351          else352            printxmmwordmem(MI, CurOp++, OS);353        }354      } else {355        printOperand(MI, CurOp++, OS);356      }357 358      return true;359    }360    break;361  }362 363  return false;364}365 366void X86IntelInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,367                                       raw_ostream &O) {368  const MCOperand &Op = MI->getOperand(OpNo);369  if (Op.isReg()) {370    printRegName(O, Op.getReg());371  } else if (Op.isImm()) {372    markup(O, Markup::Immediate) << formatImm(Op.getImm());373  } else {374    assert(Op.isExpr() && "unknown operand kind in printOperand");375    O << "offset ";376    MAI.printExpr(O, *Op.getExpr());377  }378}379 380void X86IntelInstPrinter::printMemReference(const MCInst *MI, unsigned Op,381                                            raw_ostream &O) {382  // Do not print the exact form of the memory operand if it references a known383  // binary object.384  if (SymbolizeOperands && MIA) {385    uint64_t Target;386    if (MIA->evaluateBranch(*MI, 0, 0, Target))387      return;388    if (MIA->evaluateMemoryOperandAddress(*MI, /*STI=*/nullptr, 0, 0))389      return;390  }391  const MCOperand &BaseReg  = MI->getOperand(Op+X86::AddrBaseReg);392  unsigned ScaleVal         = MI->getOperand(Op+X86::AddrScaleAmt).getImm();393  const MCOperand &IndexReg = MI->getOperand(Op+X86::AddrIndexReg);394  const MCOperand &DispSpec = MI->getOperand(Op+X86::AddrDisp);395 396  // If this has a segment register, print it.397  printOptionalSegReg(MI, Op + X86::AddrSegmentReg, O);398 399  WithMarkup M = markup(O, Markup::Memory);400  O << '[';401 402  bool NeedPlus = false;403  if (BaseReg.getReg()) {404    printOperand(MI, Op+X86::AddrBaseReg, O);405    NeedPlus = true;406  }407 408  if (IndexReg.getReg()) {409    if (NeedPlus) O << " + ";410    if (ScaleVal != 1 || !BaseReg.getReg())411      O << ScaleVal << '*';412    printOperand(MI, Op+X86::AddrIndexReg, O);413    NeedPlus = true;414  }415 416  if (!DispSpec.isImm()) {417    if (NeedPlus) O << " + ";418    assert(DispSpec.isExpr() && "non-immediate displacement for LEA?");419    MAI.printExpr(O, *DispSpec.getExpr());420  } else {421    int64_t DispVal = DispSpec.getImm();422    if (DispVal || (!IndexReg.getReg() && !BaseReg.getReg())) {423      if (NeedPlus) {424        if (DispVal > 0)425          O << " + ";426        else {427          O << " - ";428          DispVal = -DispVal;429        }430      }431      markup(O, Markup::Immediate) << formatImm(DispVal);432    }433  }434 435  O << ']';436}437 438void X86IntelInstPrinter::printSrcIdx(const MCInst *MI, unsigned Op,439                                      raw_ostream &O) {440  // If this has a segment register, print it.441  printOptionalSegReg(MI, Op + 1, O);442 443  WithMarkup M = markup(O, Markup::Memory);444  O << '[';445  printOperand(MI, Op, O);446  O << ']';447}448 449void X86IntelInstPrinter::printDstIdx(const MCInst *MI, unsigned Op,450                                      raw_ostream &O) {451  // DI accesses are always ES-based.452  O << "es:";453 454  WithMarkup M = markup(O, Markup::Memory);455  O << '[';456  printOperand(MI, Op, O);457  O << ']';458}459 460void X86IntelInstPrinter::printMemOffset(const MCInst *MI, unsigned Op,461                                         raw_ostream &O) {462  const MCOperand &DispSpec = MI->getOperand(Op);463 464  // If this has a segment register, print it.465  printOptionalSegReg(MI, Op + 1, O);466 467  WithMarkup M = markup(O, Markup::Memory);468  O << '[';469 470  if (DispSpec.isImm()) {471    markup(O, Markup::Immediate) << formatImm(DispSpec.getImm());472  } else {473    assert(DispSpec.isExpr() && "non-immediate displacement?");474    MAI.printExpr(O, *DispSpec.getExpr());475  }476 477  O << ']';478}479 480void X86IntelInstPrinter::printU8Imm(const MCInst *MI, unsigned Op,481                                     raw_ostream &O) {482  if (MI->getOperand(Op).isExpr())483    return MAI.printExpr(O, *MI->getOperand(Op).getExpr());484 485  markup(O, Markup::Immediate) << formatImm(MI->getOperand(Op).getImm() & 0xff);486}487 488void X86IntelInstPrinter::printSTiRegOperand(const MCInst *MI, unsigned OpNo,489                                            raw_ostream &OS) {490  MCRegister Reg = MI->getOperand(OpNo).getReg();491  // Override the default printing to print st(0) instead st.492  if (Reg == X86::ST0)493    OS << "st(0)";494  else495    printRegName(OS, Reg);496}497