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1//===-- ARMTargetParser - Parser for ARM target features --------*- C++ -*-===//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 implements a target parser to recognise ARM hardware features10// such as FPU/CPU/ARCH/extensions and specific support such as HWDIV.11//12//===----------------------------------------------------------------------===//13 14#include "llvm/TargetParser/ARMTargetParser.h"15#include "llvm/ADT/StringSwitch.h"16#include "llvm/Support/Format.h"17#include "llvm/Support/raw_ostream.h"18#include "llvm/TargetParser/ARMTargetParserCommon.h"19#include "llvm/TargetParser/Triple.h"20#include <cctype>21 22using namespace llvm;23 24static StringRef getHWDivSynonym(StringRef HWDiv) {25  return StringSwitch<StringRef>(HWDiv)26      .Case("thumb,arm", "arm,thumb")27      .Default(HWDiv);28}29 30// Allows partial match, ex. "v7a" matches "armv7a".31ARM::ArchKind ARM::parseArch(StringRef Arch) {32  Arch = getCanonicalArchName(Arch);33  StringRef Syn = getArchSynonym(Arch);34  for (const auto &A : ARMArchNames) {35    if (A.Name.ends_with(Syn))36      return A.ID;37  }38  return ArchKind::INVALID;39}40 41// Version number (ex. v7 = 7).42unsigned ARM::parseArchVersion(StringRef Arch) {43  Arch = getCanonicalArchName(Arch);44  switch (parseArch(Arch)) {45  case ArchKind::ARMV4:46  case ArchKind::ARMV4T:47    return 4;48  case ArchKind::ARMV5T:49  case ArchKind::ARMV5TE:50  case ArchKind::IWMMXT:51  case ArchKind::IWMMXT2:52  case ArchKind::XSCALE:53  case ArchKind::ARMV5TEJ:54    return 5;55  case ArchKind::ARMV6:56  case ArchKind::ARMV6K:57  case ArchKind::ARMV6T2:58  case ArchKind::ARMV6KZ:59  case ArchKind::ARMV6M:60    return 6;61  case ArchKind::ARMV7A:62  case ArchKind::ARMV7VE:63  case ArchKind::ARMV7R:64  case ArchKind::ARMV7M:65  case ArchKind::ARMV7S:66  case ArchKind::ARMV7EM:67  case ArchKind::ARMV7K:68    return 7;69  case ArchKind::ARMV8A:70  case ArchKind::ARMV8_1A:71  case ArchKind::ARMV8_2A:72  case ArchKind::ARMV8_3A:73  case ArchKind::ARMV8_4A:74  case ArchKind::ARMV8_5A:75  case ArchKind::ARMV8_6A:76  case ArchKind::ARMV8_7A:77  case ArchKind::ARMV8_8A:78  case ArchKind::ARMV8_9A:79  case ArchKind::ARMV8R:80  case ArchKind::ARMV8MBaseline:81  case ArchKind::ARMV8MMainline:82  case ArchKind::ARMV8_1MMainline:83    return 8;84  case ArchKind::ARMV9A:85  case ArchKind::ARMV9_1A:86  case ArchKind::ARMV9_2A:87  case ArchKind::ARMV9_3A:88  case ArchKind::ARMV9_4A:89  case ArchKind::ARMV9_5A:90  case ArchKind::ARMV9_6A:91  case ArchKind::ARMV9_7A:92    return 9;93  case ArchKind::INVALID:94    return 0;95  }96  llvm_unreachable("Unhandled architecture");97}98 99static ARM::ProfileKind getProfileKind(ARM::ArchKind AK) {100  switch (AK) {101  case ARM::ArchKind::ARMV6M:102  case ARM::ArchKind::ARMV7M:103  case ARM::ArchKind::ARMV7EM:104  case ARM::ArchKind::ARMV8MMainline:105  case ARM::ArchKind::ARMV8MBaseline:106  case ARM::ArchKind::ARMV8_1MMainline:107    return ARM::ProfileKind::M;108  case ARM::ArchKind::ARMV7R:109  case ARM::ArchKind::ARMV8R:110    return ARM::ProfileKind::R;111  case ARM::ArchKind::ARMV7A:112  case ARM::ArchKind::ARMV7VE:113  case ARM::ArchKind::ARMV7K:114  case ARM::ArchKind::ARMV8A:115  case ARM::ArchKind::ARMV8_1A:116  case ARM::ArchKind::ARMV8_2A:117  case ARM::ArchKind::ARMV8_3A:118  case ARM::ArchKind::ARMV8_4A:119  case ARM::ArchKind::ARMV8_5A:120  case ARM::ArchKind::ARMV8_6A:121  case ARM::ArchKind::ARMV8_7A:122  case ARM::ArchKind::ARMV8_8A:123  case ARM::ArchKind::ARMV8_9A:124  case ARM::ArchKind::ARMV9A:125  case ARM::ArchKind::ARMV9_1A:126  case ARM::ArchKind::ARMV9_2A:127  case ARM::ArchKind::ARMV9_3A:128  case ARM::ArchKind::ARMV9_4A:129  case ARM::ArchKind::ARMV9_5A:130  case ARM::ArchKind::ARMV9_6A:131  case ARM::ArchKind::ARMV9_7A:132    return ARM::ProfileKind::A;133  case ARM::ArchKind::ARMV4:134  case ARM::ArchKind::ARMV4T:135  case ARM::ArchKind::ARMV5T:136  case ARM::ArchKind::ARMV5TE:137  case ARM::ArchKind::ARMV5TEJ:138  case ARM::ArchKind::ARMV6:139  case ARM::ArchKind::ARMV6K:140  case ARM::ArchKind::ARMV6T2:141  case ARM::ArchKind::ARMV6KZ:142  case ARM::ArchKind::ARMV7S:143  case ARM::ArchKind::IWMMXT:144  case ARM::ArchKind::IWMMXT2:145  case ARM::ArchKind::XSCALE:146  case ARM::ArchKind::INVALID:147    return ARM::ProfileKind::INVALID;148  }149  llvm_unreachable("Unhandled architecture");150}151 152// Profile A/R/M153ARM::ProfileKind ARM::parseArchProfile(StringRef Arch) {154  Arch = getCanonicalArchName(Arch);155  return getProfileKind(parseArch(Arch));156}157 158bool ARM::getFPUFeatures(ARM::FPUKind FPUKind,159                         std::vector<StringRef> &Features) {160 161  if (FPUKind >= FK_LAST || FPUKind == FK_INVALID)162    return false;163 164  static const struct FPUFeatureNameInfo {165    const char *PlusName, *MinusName;166    FPUVersion MinVersion;167    FPURestriction MaxRestriction;168  } FPUFeatureInfoList[] = {169    // We have to specify the + and - versions of the name in full so170    // that we can return them as static StringRefs.171    //172    // Also, the SubtargetFeatures ending in just "sp" are listed here173    // under FPURestriction::None, which is the only FPURestriction in174    // which they would be valid (since FPURestriction::SP doesn't175    // exist).176    {"+vfp2", "-vfp2", FPUVersion::VFPV2, FPURestriction::D16},177    {"+vfp2sp", "-vfp2sp", FPUVersion::VFPV2, FPURestriction::SP_D16},178    {"+vfp3", "-vfp3", FPUVersion::VFPV3, FPURestriction::None},179    {"+vfp3d16", "-vfp3d16", FPUVersion::VFPV3, FPURestriction::D16},180    {"+vfp3d16sp", "-vfp3d16sp", FPUVersion::VFPV3, FPURestriction::SP_D16},181    {"+vfp3sp", "-vfp3sp", FPUVersion::VFPV3, FPURestriction::None},182    {"+fp16", "-fp16", FPUVersion::VFPV3_FP16, FPURestriction::SP_D16},183    {"+vfp4", "-vfp4", FPUVersion::VFPV4, FPURestriction::None},184    {"+vfp4d16", "-vfp4d16", FPUVersion::VFPV4, FPURestriction::D16},185    {"+vfp4d16sp", "-vfp4d16sp", FPUVersion::VFPV4, FPURestriction::SP_D16},186    {"+vfp4sp", "-vfp4sp", FPUVersion::VFPV4, FPURestriction::None},187    {"+fp-armv8", "-fp-armv8", FPUVersion::VFPV5, FPURestriction::None},188    {"+fp-armv8d16", "-fp-armv8d16", FPUVersion::VFPV5, FPURestriction::D16},189    {"+fp-armv8d16sp", "-fp-armv8d16sp", FPUVersion::VFPV5, FPURestriction::SP_D16},190    {"+fp-armv8sp", "-fp-armv8sp", FPUVersion::VFPV5, FPURestriction::None},191    {"+fullfp16", "-fullfp16", FPUVersion::VFPV5_FULLFP16, FPURestriction::SP_D16},192    {"+fp64", "-fp64", FPUVersion::VFPV2, FPURestriction::D16},193    {"+d32", "-d32", FPUVersion::VFPV3, FPURestriction::None},194  };195 196  for (const auto &Info: FPUFeatureInfoList) {197    if (FPUNames[FPUKind].FPUVer >= Info.MinVersion &&198        FPUNames[FPUKind].Restriction <= Info.MaxRestriction)199      Features.push_back(Info.PlusName);200    else201      Features.push_back(Info.MinusName);202  }203 204  static const struct NeonFeatureNameInfo {205    const char *PlusName, *MinusName;206    NeonSupportLevel MinSupportLevel;207  } NeonFeatureInfoList[] = {208      {"+neon", "-neon", NeonSupportLevel::Neon},209      {"+sha2", "-sha2", NeonSupportLevel::Crypto},210      {"+aes", "-aes", NeonSupportLevel::Crypto},211  };212 213  for (const auto &Info: NeonFeatureInfoList) {214    if (FPUNames[FPUKind].NeonSupport >= Info.MinSupportLevel)215      Features.push_back(Info.PlusName);216    else217      Features.push_back(Info.MinusName);218  }219 220  return true;221}222 223ARM::FPUKind ARM::parseFPU(StringRef FPU) {224  StringRef Syn = getFPUSynonym(FPU);225  for (const auto &F : FPUNames) {226    if (Syn == F.Name)227      return F.ID;228  }229  return FK_INVALID;230}231 232ARM::NeonSupportLevel ARM::getFPUNeonSupportLevel(ARM::FPUKind FPUKind) {233  if (FPUKind >= FK_LAST)234    return NeonSupportLevel::None;235  return FPUNames[FPUKind].NeonSupport;236}237 238StringRef ARM::getFPUSynonym(StringRef FPU) {239  return StringSwitch<StringRef>(FPU)240      .Cases({"fpa", "fpe2", "fpe3", "maverick"}, "invalid") // Unsupported241      .Case("vfp2", "vfpv2")242      .Case("vfp3", "vfpv3")243      .Case("vfp4", "vfpv4")244      .Case("vfp3-d16", "vfpv3-d16")245      .Case("vfp4-d16", "vfpv4-d16")246      .Cases({"fp4-sp-d16", "vfpv4-sp-d16"}, "fpv4-sp-d16")247      .Cases({"fp4-dp-d16", "fpv4-dp-d16"}, "vfpv4-d16")248      .Case("fp5-sp-d16", "fpv5-sp-d16")249      .Cases({"fp5-dp-d16", "fpv5-dp-d16"}, "fpv5-d16")250      // FIXME: Clang uses it, but it's bogus, since neon defaults to vfpv3.251      .Case("neon-vfpv3", "neon")252      .Default(FPU);253}254 255StringRef ARM::getFPUName(ARM::FPUKind FPUKind) {256  if (FPUKind >= FK_LAST)257    return StringRef();258  return FPUNames[FPUKind].Name;259}260 261ARM::FPUVersion ARM::getFPUVersion(ARM::FPUKind FPUKind) {262  if (FPUKind >= FK_LAST)263    return FPUVersion::NONE;264  return FPUNames[FPUKind].FPUVer;265}266 267ARM::FPURestriction ARM::getFPURestriction(ARM::FPUKind FPUKind) {268  if (FPUKind >= FK_LAST)269    return FPURestriction::None;270  return FPUNames[FPUKind].Restriction;271}272 273ARM::FPUKind ARM::getDefaultFPU(StringRef CPU, ARM::ArchKind AK) {274  if (CPU == "generic")275    return ARM::ARMArchNames[static_cast<unsigned>(AK)].DefaultFPU;276 277  return StringSwitch<ARM::FPUKind>(CPU)278#define ARM_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT)           \279  .Case(NAME, DEFAULT_FPU)280#include "llvm/TargetParser/ARMTargetParser.def"281      .Default(ARM::FK_INVALID);282}283 284uint64_t ARM::getDefaultExtensions(StringRef CPU, ARM::ArchKind AK) {285  if (CPU == "generic")286    return ARM::ARMArchNames[static_cast<unsigned>(AK)].ArchBaseExtensions;287 288  return StringSwitch<uint64_t>(CPU)289#define ARM_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT)           \290  .Case(NAME,                                                                  \291        ARMArchNames[static_cast<unsigned>(ArchKind::ID)].ArchBaseExtensions | \292            DEFAULT_EXT)293#include "llvm/TargetParser/ARMTargetParser.def"294  .Default(ARM::AEK_INVALID);295}296 297bool ARM::getHWDivFeatures(uint64_t HWDivKind,298                           std::vector<StringRef> &Features) {299 300  if (HWDivKind == AEK_INVALID)301    return false;302 303  if (HWDivKind & AEK_HWDIVARM)304    Features.push_back("+hwdiv-arm");305  else306    Features.push_back("-hwdiv-arm");307 308  if (HWDivKind & AEK_HWDIVTHUMB)309    Features.push_back("+hwdiv");310  else311    Features.push_back("-hwdiv");312 313  return true;314}315 316bool ARM::getExtensionFeatures(uint64_t Extensions,317                               std::vector<StringRef> &Features) {318 319  if (Extensions == AEK_INVALID)320    return false;321 322  for (const auto &AE : ARCHExtNames) {323    if ((Extensions & AE.ID) == AE.ID && !AE.Feature.empty())324      Features.push_back(AE.Feature);325    else if (!AE.NegFeature.empty())326      Features.push_back(AE.NegFeature);327  }328 329  return getHWDivFeatures(Extensions, Features);330}331 332StringRef ARM::getArchName(ARM::ArchKind AK) {333  return ARMArchNames[static_cast<unsigned>(AK)].Name;334}335 336StringRef ARM::getCPUAttr(ARM::ArchKind AK) {337  return ARMArchNames[static_cast<unsigned>(AK)].CPUAttr;338}339 340StringRef ARM::getSubArch(ARM::ArchKind AK) {341  return ARMArchNames[static_cast<unsigned>(AK)].getSubArch();342}343 344unsigned ARM::getArchAttr(ARM::ArchKind AK) {345  return ARMArchNames[static_cast<unsigned>(AK)].ArchAttr;346}347 348StringRef ARM::getArchExtName(uint64_t ArchExtKind) {349  for (const auto &AE : ARCHExtNames) {350    if (ArchExtKind == AE.ID)351      return AE.Name;352  }353  return StringRef();354}355 356static bool stripNegationPrefix(StringRef &Name) {357  return Name.consume_front("no");358}359 360StringRef ARM::getArchExtFeature(StringRef ArchExt) {361  bool Negated = stripNegationPrefix(ArchExt);362  for (const auto &AE : ARCHExtNames) {363    if (!AE.Feature.empty() && ArchExt == AE.Name)364      return StringRef(Negated ? AE.NegFeature : AE.Feature);365  }366 367  return StringRef();368}369 370static ARM::FPUKind findDoublePrecisionFPU(ARM::FPUKind InputFPUKind) {371  if (InputFPUKind == ARM::FK_INVALID || InputFPUKind == ARM::FK_NONE)372    return ARM::FK_INVALID;373 374  const ARM::FPUName &InputFPU = ARM::FPUNames[InputFPUKind];375 376  // If the input FPU already supports double-precision, then there377  // isn't any different FPU we can return here.378  if (ARM::isDoublePrecision(InputFPU.Restriction))379    return InputFPUKind;380 381  // Otherwise, look for an FPU entry with all the same fields, except382  // that it supports double precision.383  for (const ARM::FPUName &CandidateFPU : ARM::FPUNames) {384    if (CandidateFPU.FPUVer == InputFPU.FPUVer &&385        CandidateFPU.NeonSupport == InputFPU.NeonSupport &&386        ARM::has32Regs(CandidateFPU.Restriction) ==387            ARM::has32Regs(InputFPU.Restriction) &&388        ARM::isDoublePrecision(CandidateFPU.Restriction)) {389      return CandidateFPU.ID;390    }391  }392 393  // nothing found394  return ARM::FK_INVALID;395}396 397static ARM::FPUKind findSinglePrecisionFPU(ARM::FPUKind InputFPUKind) {398  if (InputFPUKind == ARM::FK_INVALID || InputFPUKind == ARM::FK_NONE)399    return ARM::FK_INVALID;400 401  const ARM::FPUName &InputFPU = ARM::FPUNames[InputFPUKind];402 403  // If the input FPU already is single-precision only, then there404  // isn't any different FPU we can return here.405  if (!ARM::isDoublePrecision(InputFPU.Restriction))406    return InputFPUKind;407 408  // Otherwise, look for an FPU entry that has the same FPUVer409  // and is not Double Precision. We want to allow for changing of410  // NEON Support and Restrictions so CPU's such as Cortex-R52 can411  // select between SP Only and Full DP modes.412  for (const ARM::FPUName &CandidateFPU : ARM::FPUNames) {413    if (CandidateFPU.FPUVer == InputFPU.FPUVer &&414        !ARM::isDoublePrecision(CandidateFPU.Restriction)) {415      return CandidateFPU.ID;416    }417  }418 419  // nothing found420  return ARM::FK_INVALID;421}422 423bool ARM::appendArchExtFeatures(StringRef CPU, ARM::ArchKind AK,424                                StringRef ArchExt,425                                std::vector<StringRef> &Features,426                                ARM::FPUKind &ArgFPUKind) {427 428  size_t StartingNumFeatures = Features.size();429  const bool Negated = stripNegationPrefix(ArchExt);430  uint64_t ID = parseArchExt(ArchExt);431 432  if (ID == AEK_INVALID)433    return false;434 435  for (const auto &AE : ARCHExtNames) {436    if (Negated) {437      if ((AE.ID & ID) == ID && !AE.NegFeature.empty())438        Features.push_back(AE.NegFeature);439    } else {440      if ((AE.ID & ID) == AE.ID && !AE.Feature.empty())441        Features.push_back(AE.Feature);442    }443  }444 445  if (CPU == "")446    CPU = "generic";447 448  if (ArchExt == "fp" || ArchExt == "fp.dp") {449    const ARM::FPUKind DefaultFPU = getDefaultFPU(CPU, AK);450    ARM::FPUKind FPUKind;451    if (ArchExt == "fp.dp") {452      const bool IsDP = ArgFPUKind != ARM::FK_INVALID &&453                        ArgFPUKind != ARM::FK_NONE &&454                        isDoublePrecision(getFPURestriction(ArgFPUKind));455      if (Negated) {456        /* If there is no FPU selected yet, we still need to set ArgFPUKind, as457         * leaving it as FK_INVALID, would cause default FPU to be selected458         * later and that could be double precision one. */459        if (ArgFPUKind != ARM::FK_INVALID && !IsDP)460          return true;461        FPUKind = findSinglePrecisionFPU(DefaultFPU);462        if (FPUKind == ARM::FK_INVALID)463          FPUKind = ARM::FK_NONE;464      } else {465        if (IsDP)466          return true;467        FPUKind = findDoublePrecisionFPU(DefaultFPU);468        if (FPUKind == ARM::FK_INVALID)469          return false;470      }471    } else if (Negated) {472      FPUKind = ARM::FK_NONE;473    } else {474      FPUKind = DefaultFPU;475    }476    ArgFPUKind = FPUKind;477    return true;478  }479  return StartingNumFeatures != Features.size();480}481 482ARM::ArchKind ARM::convertV9toV8(ARM::ArchKind AK) {483  if (getProfileKind(AK) != ProfileKind::A)484    return ARM::ArchKind::INVALID;485  if (AK < ARM::ArchKind::ARMV9A || AK > ARM::ArchKind::ARMV9_3A)486    return ARM::ArchKind::INVALID;487  unsigned AK_v8 = static_cast<unsigned>(ARM::ArchKind::ARMV8_5A);488  AK_v8 += static_cast<unsigned>(AK) -489           static_cast<unsigned>(ARM::ArchKind::ARMV9A);490  return static_cast<ARM::ArchKind>(AK_v8);491}492 493StringRef ARM::getDefaultCPU(StringRef Arch) {494  ArchKind AK = parseArch(Arch);495  if (AK == ArchKind::INVALID)496    return StringRef();497 498  // Look for multiple AKs to find the default for pair AK+Name.499  for (const auto &CPU : CPUNames) {500    if (CPU.ArchID == AK && CPU.Default)501      return CPU.Name;502  }503 504  // If we can't find a default then target the architecture instead505  return "generic";506}507 508uint64_t ARM::parseHWDiv(StringRef HWDiv) {509  StringRef Syn = getHWDivSynonym(HWDiv);510  for (const auto &D : HWDivNames) {511    if (Syn == D.Name)512      return D.ID;513  }514  return AEK_INVALID;515}516 517uint64_t ARM::parseArchExt(StringRef ArchExt) {518  for (const auto &A : ARCHExtNames) {519    if (ArchExt == A.Name)520      return A.ID;521  }522  return AEK_INVALID;523}524 525ARM::ArchKind ARM::parseCPUArch(StringRef CPU) {526  for (const auto &C : CPUNames) {527    if (CPU == C.Name)528      return C.ArchID;529  }530  return ArchKind::INVALID;531}532 533void ARM::fillValidCPUArchList(SmallVectorImpl<StringRef> &Values) {534  for (const auto &Arch : CPUNames) {535    if (Arch.ArchID != ArchKind::INVALID)536      Values.push_back(Arch.Name);537  }538}539 540StringRef ARM::computeDefaultTargetABI(const Triple &TT) {541  StringRef ArchName = TT.getArchName();542 543  if (TT.isOSBinFormatMachO()) {544    if (TT.getEnvironment() == Triple::EABI ||545        TT.getOS() == Triple::UnknownOS ||546        parseArchProfile(ArchName) == ProfileKind::M)547      return "aapcs";548    if (TT.isWatchABI())549      return "aapcs16";550    return "apcs-gnu";551  } else if (TT.isOSWindows())552    // FIXME: this is invalid for WindowsCE.553    return "aapcs";554 555  // Select the default based on the platform.556  switch (TT.getEnvironment()) {557  case Triple::Android:558  case Triple::GNUEABI:559  case Triple::GNUEABIT64:560  case Triple::GNUEABIHF:561  case Triple::GNUEABIHFT64:562  case Triple::MuslEABI:563  case Triple::MuslEABIHF:564  case Triple::OpenHOS:565    return "aapcs-linux";566  case Triple::EABIHF:567  case Triple::EABI:568    return "aapcs";569  default:570    if (TT.isOSNetBSD())571      return "apcs-gnu";572    if (TT.isOSFreeBSD() || TT.isOSFuchsia() || TT.isOSOpenBSD() ||573        TT.isOSHaiku() || TT.isOHOSFamily())574      return "aapcs-linux";575    return "aapcs";576  }577}578 579ARM::ARMABI ARM::computeTargetABI(const Triple &TT, StringRef ABIName) {580  if (ABIName.empty())581    ABIName = ARM::computeDefaultTargetABI(TT);582 583  if (ABIName == "aapcs16")584    return ARM_ABI_AAPCS16;585 586  if (ABIName.starts_with("aapcs"))587    return ARM_ABI_AAPCS;588 589  if (ABIName.starts_with("apcs"))590    return ARM_ABI_APCS;591 592  return ARM_ABI_UNKNOWN;593}594 595StringRef ARM::getARMCPUForArch(const llvm::Triple &Triple, StringRef MArch) {596  if (MArch.empty())597    MArch = Triple.getArchName();598  MArch = llvm::ARM::getCanonicalArchName(MArch);599 600  // Some defaults are forced.601  switch (Triple.getOS()) {602  case llvm::Triple::FreeBSD:603  case llvm::Triple::NetBSD:604  case llvm::Triple::OpenBSD:605  case llvm::Triple::Haiku:606    if (!MArch.empty() && MArch == "v6")607      return "arm1176jzf-s";608    if (!MArch.empty() && MArch == "v7")609      return "cortex-a8";610    break;611  case llvm::Triple::Win32:612    // FIXME: this is invalid for WindowsCE613    if (llvm::ARM::parseArchVersion(MArch) <= 7)614      return "cortex-a9";615    break;616  case llvm::Triple::IOS:617  case llvm::Triple::MacOSX:618  case llvm::Triple::TvOS:619  case llvm::Triple::WatchOS:620  case llvm::Triple::DriverKit:621  case llvm::Triple::XROS:622    if (MArch == "v7k")623      return "cortex-a7";624    break;625  default:626    break;627  }628 629  if (MArch.empty())630    return StringRef();631 632  StringRef CPU = llvm::ARM::getDefaultCPU(MArch);633  if (!CPU.empty() && CPU != "invalid")634    return CPU;635 636  // If no specific architecture version is requested, return the minimum CPU637  // required by the OS and environment.638  switch (Triple.getOS()) {639  case llvm::Triple::Haiku:640    return "arm1176jzf-s";641  case llvm::Triple::NetBSD:642    switch (Triple.getEnvironment()) {643    case llvm::Triple::EABI:644    case llvm::Triple::EABIHF:645    case llvm::Triple::GNUEABI:646    case llvm::Triple::GNUEABIHF:647      return "arm926ej-s";648    default:649      return "strongarm";650    }651  case llvm::Triple::OpenBSD:652    return "cortex-a8";653  case llvm::Triple::Fuchsia:654    return "cortex-a53";655  default:656    switch (Triple.getEnvironment()) {657    case llvm::Triple::EABIHF:658    case llvm::Triple::GNUEABIHF:659    case llvm::Triple::GNUEABIHFT64:660    case llvm::Triple::MuslEABIHF:661      return "arm1176jzf-s";662    default:663      return "arm7tdmi";664    }665  }666 667  llvm_unreachable("invalid arch name");668}669 670void ARM::PrintSupportedExtensions(StringMap<StringRef> DescMap) {671  outs() << "All available -march extensions for ARM\n\n"672         << "    " << left_justify("Name", 20)673         << (DescMap.empty() ? "\n" : "Description\n");674  for (const auto &Ext : ARCHExtNames) {675    // Extensions without a feature cannot be used with -march.676    if (!Ext.Feature.empty()) {677      std::string Description = DescMap[Ext.Name].str();678      // With SIMD, this links to the NEON feature, so the description should be679      // taken from here, as SIMD does not exist in TableGen.680      if (Ext.Name == "simd")681        Description = DescMap["neon"].str();682      outs() << "    "683             << format(Description.empty() ? "%s\n" : "%-20s%s\n",684                       Ext.Name.str().c_str(), Description.c_str());685    }686  }687}688