1 //===--- AArch64.cpp - AArch64 (not ARM) Helpers for Tools ------*- 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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "AArch64.h" 10 #include "clang/Driver/Driver.h" 11 #include "clang/Driver/DriverDiagnostic.h" 12 #include "clang/Driver/Options.h" 13 #include "llvm/Option/ArgList.h" 14 #include "llvm/Support/TargetParser.h" 15 #include "llvm/Support/Host.h" 16 17 using namespace clang::driver; 18 using namespace clang::driver::tools; 19 using namespace clang; 20 using namespace llvm::opt; 21 22 /// \returns true if the given triple can determine the default CPU type even 23 /// if -arch is not specified. 24 static bool isCPUDeterminedByTriple(const llvm::Triple &Triple) { 25 return Triple.isOSDarwin(); 26 } 27 28 /// getAArch64TargetCPU - Get the (LLVM) name of the AArch64 cpu we are 29 /// targeting. Set \p A to the Arg corresponding to the -mcpu argument if it is 30 /// provided, or to nullptr otherwise. 31 std::string aarch64::getAArch64TargetCPU(const ArgList &Args, 32 const llvm::Triple &Triple, Arg *&A) { 33 std::string CPU; 34 // If we have -mcpu, use that. 35 if ((A = Args.getLastArg(options::OPT_mcpu_EQ))) { 36 StringRef Mcpu = A->getValue(); 37 CPU = Mcpu.split("+").first.lower(); 38 } 39 40 // Handle CPU name is 'native'. 41 if (CPU == "native") 42 return std::string(llvm::sys::getHostCPUName()); 43 44 if (CPU.size()) 45 return CPU; 46 47 if (Triple.isTargetMachineMac() && 48 Triple.getArch() == llvm::Triple::aarch64) { 49 // Apple Silicon macs default to M1 CPUs. 50 return "apple-m1"; 51 } 52 53 // arm64e requires v8.3a and only runs on apple-a12 and later CPUs. 54 if (Triple.isArm64e()) 55 return "apple-a12"; 56 57 // Make sure we pick the appropriate Apple CPU if -arch is used or when 58 // targetting a Darwin OS. 59 if (Args.getLastArg(options::OPT_arch) || Triple.isOSDarwin()) 60 return Triple.getArch() == llvm::Triple::aarch64_32 ? "apple-s4" 61 : "apple-a7"; 62 63 return "generic"; 64 } 65 66 // Decode AArch64 features from string like +[no]featureA+[no]featureB+... 67 static bool DecodeAArch64Features(const Driver &D, StringRef text, 68 std::vector<StringRef> &Features, 69 llvm::AArch64::ArchKind ArchKind) { 70 SmallVector<StringRef, 8> Split; 71 text.split(Split, StringRef("+"), -1, false); 72 73 for (StringRef Feature : Split) { 74 StringRef FeatureName = llvm::AArch64::getArchExtFeature(Feature); 75 if (!FeatureName.empty()) 76 Features.push_back(FeatureName); 77 else if (Feature == "neon" || Feature == "noneon") 78 D.Diag(clang::diag::err_drv_no_neon_modifier); 79 else 80 return false; 81 82 // +sve implies +f32mm if the base architecture is v8.6A or v8.7A 83 // it isn't the case in general that sve implies both f64mm and f32mm 84 if ((ArchKind == llvm::AArch64::ArchKind::ARMV8_6A || 85 ArchKind == llvm::AArch64::ArchKind::ARMV8_7A) && Feature == "sve") 86 Features.push_back("+f32mm"); 87 } 88 return true; 89 } 90 91 // Check if the CPU name and feature modifiers in -mcpu are legal. If yes, 92 // decode CPU and feature. 93 static bool DecodeAArch64Mcpu(const Driver &D, StringRef Mcpu, StringRef &CPU, 94 std::vector<StringRef> &Features) { 95 std::pair<StringRef, StringRef> Split = Mcpu.split("+"); 96 CPU = Split.first; 97 llvm::AArch64::ArchKind ArchKind = llvm::AArch64::ArchKind::ARMV8A; 98 99 if (CPU == "native") 100 CPU = llvm::sys::getHostCPUName(); 101 102 if (CPU == "generic") { 103 Features.push_back("+neon"); 104 } else { 105 ArchKind = llvm::AArch64::parseCPUArch(CPU); 106 if (!llvm::AArch64::getArchFeatures(ArchKind, Features)) 107 return false; 108 109 uint64_t Extension = llvm::AArch64::getDefaultExtensions(CPU, ArchKind); 110 if (!llvm::AArch64::getExtensionFeatures(Extension, Features)) 111 return false; 112 } 113 114 if (Split.second.size() && 115 !DecodeAArch64Features(D, Split.second, Features, ArchKind)) 116 return false; 117 118 return true; 119 } 120 121 static bool 122 getAArch64ArchFeaturesFromMarch(const Driver &D, StringRef March, 123 const ArgList &Args, 124 std::vector<StringRef> &Features) { 125 std::string MarchLowerCase = March.lower(); 126 std::pair<StringRef, StringRef> Split = StringRef(MarchLowerCase).split("+"); 127 128 llvm::AArch64::ArchKind ArchKind = llvm::AArch64::parseArch(Split.first); 129 if (ArchKind == llvm::AArch64::ArchKind::INVALID || 130 !llvm::AArch64::getArchFeatures(ArchKind, Features) || 131 (Split.second.size() && 132 !DecodeAArch64Features(D, Split.second, Features, ArchKind))) 133 return false; 134 135 return true; 136 } 137 138 static bool 139 getAArch64ArchFeaturesFromMcpu(const Driver &D, StringRef Mcpu, 140 const ArgList &Args, 141 std::vector<StringRef> &Features) { 142 StringRef CPU; 143 std::string McpuLowerCase = Mcpu.lower(); 144 if (!DecodeAArch64Mcpu(D, McpuLowerCase, CPU, Features)) 145 return false; 146 147 return true; 148 } 149 150 static bool 151 getAArch64MicroArchFeaturesFromMtune(const Driver &D, StringRef Mtune, 152 const ArgList &Args, 153 std::vector<StringRef> &Features) { 154 std::string MtuneLowerCase = Mtune.lower(); 155 // Check CPU name is valid 156 std::vector<StringRef> MtuneFeatures; 157 StringRef Tune; 158 if (!DecodeAArch64Mcpu(D, MtuneLowerCase, Tune, MtuneFeatures)) 159 return false; 160 161 // Handle CPU name is 'native'. 162 if (MtuneLowerCase == "native") 163 MtuneLowerCase = std::string(llvm::sys::getHostCPUName()); 164 if (MtuneLowerCase == "cyclone" || 165 StringRef(MtuneLowerCase).startswith("apple")) { 166 Features.push_back("+zcm"); 167 Features.push_back("+zcz"); 168 } 169 return true; 170 } 171 172 static bool 173 getAArch64MicroArchFeaturesFromMcpu(const Driver &D, StringRef Mcpu, 174 const ArgList &Args, 175 std::vector<StringRef> &Features) { 176 StringRef CPU; 177 std::vector<StringRef> DecodedFeature; 178 std::string McpuLowerCase = Mcpu.lower(); 179 if (!DecodeAArch64Mcpu(D, McpuLowerCase, CPU, DecodedFeature)) 180 return false; 181 182 return getAArch64MicroArchFeaturesFromMtune(D, CPU, Args, Features); 183 } 184 185 void aarch64::getAArch64TargetFeatures(const Driver &D, 186 const llvm::Triple &Triple, 187 const ArgList &Args, 188 std::vector<StringRef> &Features, 189 bool ForAS) { 190 Arg *A; 191 bool success = true; 192 // Enable NEON by default. 193 Features.push_back("+neon"); 194 llvm::StringRef WaMArch; 195 if (ForAS) 196 for (const auto *A : 197 Args.filtered(options::OPT_Wa_COMMA, options::OPT_Xassembler)) 198 for (StringRef Value : A->getValues()) 199 if (Value.startswith("-march=")) 200 WaMArch = Value.substr(7); 201 // Call getAArch64ArchFeaturesFromMarch only if "-Wa,-march=" or 202 // "-Xassembler -march" is detected. Otherwise it may return false 203 // and causes Clang to error out. 204 if (!WaMArch.empty()) 205 success = getAArch64ArchFeaturesFromMarch(D, WaMArch, Args, Features); 206 else if ((A = Args.getLastArg(options::OPT_march_EQ))) 207 success = getAArch64ArchFeaturesFromMarch(D, A->getValue(), Args, Features); 208 else if ((A = Args.getLastArg(options::OPT_mcpu_EQ))) 209 success = getAArch64ArchFeaturesFromMcpu(D, A->getValue(), Args, Features); 210 else if (Args.hasArg(options::OPT_arch) || isCPUDeterminedByTriple(Triple)) 211 success = getAArch64ArchFeaturesFromMcpu( 212 D, getAArch64TargetCPU(Args, Triple, A), Args, Features); 213 214 if (success && (A = Args.getLastArg(clang::driver::options::OPT_mtune_EQ))) 215 success = 216 getAArch64MicroArchFeaturesFromMtune(D, A->getValue(), Args, Features); 217 else if (success && (A = Args.getLastArg(options::OPT_mcpu_EQ))) 218 success = 219 getAArch64MicroArchFeaturesFromMcpu(D, A->getValue(), Args, Features); 220 else if (success && 221 (Args.hasArg(options::OPT_arch) || isCPUDeterminedByTriple(Triple))) 222 success = getAArch64MicroArchFeaturesFromMcpu( 223 D, getAArch64TargetCPU(Args, Triple, A), Args, Features); 224 225 if (!success) { 226 auto Diag = D.Diag(diag::err_drv_clang_unsupported); 227 // If "-Wa,-march=" is used, 'WaMArch' will contain the argument's value, 228 // while 'A' is uninitialized. Only dereference 'A' in the other case. 229 if (!WaMArch.empty()) 230 Diag << "-march=" + WaMArch.str(); 231 else 232 Diag << A->getAsString(Args); 233 } 234 235 if (Args.getLastArg(options::OPT_mgeneral_regs_only)) { 236 Features.push_back("-fp-armv8"); 237 Features.push_back("-crypto"); 238 Features.push_back("-neon"); 239 } 240 241 if (Arg *A = Args.getLastArg(options::OPT_mtp_mode_EQ)) { 242 StringRef Mtp = A->getValue(); 243 if (Mtp == "el3") 244 Features.push_back("+tpidr-el3"); 245 else if (Mtp == "el2") 246 Features.push_back("+tpidr-el2"); 247 else if (Mtp == "el1") 248 Features.push_back("+tpidr-el1"); 249 else if (Mtp != "el0") 250 D.Diag(diag::err_drv_invalid_mtp) << A->getAsString(Args); 251 } 252 253 // Enable/disable straight line speculation hardening. 254 if (Arg *A = Args.getLastArg(options::OPT_mharden_sls_EQ)) { 255 StringRef Scope = A->getValue(); 256 bool EnableRetBr = false; 257 bool EnableBlr = false; 258 bool DisableComdat = false; 259 if (Scope != "none") { 260 SmallVector<StringRef, 4> Opts; 261 Scope.split(Opts, ","); 262 for (auto Opt : Opts) { 263 Opt = Opt.trim(); 264 if (Opt == "all") { 265 EnableBlr = true; 266 EnableRetBr = true; 267 continue; 268 } 269 if (Opt == "retbr") { 270 EnableRetBr = true; 271 continue; 272 } 273 if (Opt == "blr") { 274 EnableBlr = true; 275 continue; 276 } 277 if (Opt == "comdat") { 278 DisableComdat = false; 279 continue; 280 } 281 if (Opt == "nocomdat") { 282 DisableComdat = true; 283 continue; 284 } 285 D.Diag(diag::err_invalid_sls_hardening) 286 << Scope << A->getAsString(Args); 287 break; 288 } 289 } 290 291 if (EnableRetBr) 292 Features.push_back("+harden-sls-retbr"); 293 if (EnableBlr) 294 Features.push_back("+harden-sls-blr"); 295 if (DisableComdat) { 296 Features.push_back("+harden-sls-nocomdat"); 297 } 298 } 299 300 // En/disable crc 301 if (Arg *A = Args.getLastArg(options::OPT_mcrc, options::OPT_mnocrc)) { 302 if (A->getOption().matches(options::OPT_mcrc)) 303 Features.push_back("+crc"); 304 else 305 Features.push_back("-crc"); 306 } 307 308 // Handle (arch-dependent) fp16fml/fullfp16 relationship. 309 // FIXME: this fp16fml option handling will be reimplemented after the 310 // TargetParser rewrite. 311 const auto ItRNoFullFP16 = std::find(Features.rbegin(), Features.rend(), "-fullfp16"); 312 const auto ItRFP16FML = std::find(Features.rbegin(), Features.rend(), "+fp16fml"); 313 if (llvm::is_contained(Features, "+v8.4a")) { 314 const auto ItRFullFP16 = std::find(Features.rbegin(), Features.rend(), "+fullfp16"); 315 if (ItRFullFP16 < ItRNoFullFP16 && ItRFullFP16 < ItRFP16FML) { 316 // Only entangled feature that can be to the right of this +fullfp16 is -fp16fml. 317 // Only append the +fp16fml if there is no -fp16fml after the +fullfp16. 318 if (std::find(Features.rbegin(), ItRFullFP16, "-fp16fml") == ItRFullFP16) 319 Features.push_back("+fp16fml"); 320 } 321 else 322 goto fp16_fml_fallthrough; 323 } else { 324 fp16_fml_fallthrough: 325 // In both of these cases, putting the 'other' feature on the end of the vector will 326 // result in the same effect as placing it immediately after the current feature. 327 if (ItRNoFullFP16 < ItRFP16FML) 328 Features.push_back("-fp16fml"); 329 else if (ItRNoFullFP16 > ItRFP16FML) 330 Features.push_back("+fullfp16"); 331 } 332 333 // FIXME: this needs reimplementation too after the TargetParser rewrite 334 // 335 // Context sensitive meaning of Crypto: 336 // 1) For Arch >= ARMv8.4a: crypto = sm4 + sha3 + sha2 + aes 337 // 2) For Arch <= ARMv8.3a: crypto = sha2 + aes 338 const auto ItBegin = Features.begin(); 339 const auto ItEnd = Features.end(); 340 const auto ItRBegin = Features.rbegin(); 341 const auto ItREnd = Features.rend(); 342 const auto ItRCrypto = std::find(ItRBegin, ItREnd, "+crypto"); 343 const auto ItRNoCrypto = std::find(ItRBegin, ItREnd, "-crypto"); 344 const auto HasCrypto = ItRCrypto != ItREnd; 345 const auto HasNoCrypto = ItRNoCrypto != ItREnd; 346 const ptrdiff_t PosCrypto = ItRCrypto - ItRBegin; 347 const ptrdiff_t PosNoCrypto = ItRNoCrypto - ItRBegin; 348 349 bool NoCrypto = false; 350 if (HasCrypto && HasNoCrypto) { 351 if (PosNoCrypto < PosCrypto) 352 NoCrypto = true; 353 } 354 355 if (std::find(ItBegin, ItEnd, "+v8.4a") != ItEnd) { 356 if (HasCrypto && !NoCrypto) { 357 // Check if we have NOT disabled an algorithm with something like: 358 // +crypto, -algorithm 359 // And if "-algorithm" does not occur, we enable that crypto algorithm. 360 const bool HasSM4 = (std::find(ItBegin, ItEnd, "-sm4") == ItEnd); 361 const bool HasSHA3 = (std::find(ItBegin, ItEnd, "-sha3") == ItEnd); 362 const bool HasSHA2 = (std::find(ItBegin, ItEnd, "-sha2") == ItEnd); 363 const bool HasAES = (std::find(ItBegin, ItEnd, "-aes") == ItEnd); 364 if (HasSM4) 365 Features.push_back("+sm4"); 366 if (HasSHA3) 367 Features.push_back("+sha3"); 368 if (HasSHA2) 369 Features.push_back("+sha2"); 370 if (HasAES) 371 Features.push_back("+aes"); 372 } else if (HasNoCrypto) { 373 // Check if we have NOT enabled a crypto algorithm with something like: 374 // -crypto, +algorithm 375 // And if "+algorithm" does not occur, we disable that crypto algorithm. 376 const bool HasSM4 = (std::find(ItBegin, ItEnd, "+sm4") != ItEnd); 377 const bool HasSHA3 = (std::find(ItBegin, ItEnd, "+sha3") != ItEnd); 378 const bool HasSHA2 = (std::find(ItBegin, ItEnd, "+sha2") != ItEnd); 379 const bool HasAES = (std::find(ItBegin, ItEnd, "+aes") != ItEnd); 380 if (!HasSM4) 381 Features.push_back("-sm4"); 382 if (!HasSHA3) 383 Features.push_back("-sha3"); 384 if (!HasSHA2) 385 Features.push_back("-sha2"); 386 if (!HasAES) 387 Features.push_back("-aes"); 388 } 389 } else { 390 if (HasCrypto && !NoCrypto) { 391 const bool HasSHA2 = (std::find(ItBegin, ItEnd, "-sha2") == ItEnd); 392 const bool HasAES = (std::find(ItBegin, ItEnd, "-aes") == ItEnd); 393 if (HasSHA2) 394 Features.push_back("+sha2"); 395 if (HasAES) 396 Features.push_back("+aes"); 397 } else if (HasNoCrypto) { 398 const bool HasSHA2 = (std::find(ItBegin, ItEnd, "+sha2") != ItEnd); 399 const bool HasAES = (std::find(ItBegin, ItEnd, "+aes") != ItEnd); 400 const bool HasV82a = (std::find(ItBegin, ItEnd, "+v8.2a") != ItEnd); 401 const bool HasV83a = (std::find(ItBegin, ItEnd, "+v8.3a") != ItEnd); 402 const bool HasV84a = (std::find(ItBegin, ItEnd, "+v8.4a") != ItEnd); 403 if (!HasSHA2) 404 Features.push_back("-sha2"); 405 if (!HasAES) 406 Features.push_back("-aes"); 407 if (HasV82a || HasV83a || HasV84a) { 408 Features.push_back("-sm4"); 409 Features.push_back("-sha3"); 410 } 411 } 412 } 413 414 auto V8_6Pos = llvm::find(Features, "+v8.6a"); 415 if (V8_6Pos != std::end(Features)) 416 V8_6Pos = Features.insert(std::next(V8_6Pos), {"+i8mm", "+bf16"}); 417 418 if (Arg *A = Args.getLastArg(options::OPT_mno_unaligned_access, 419 options::OPT_munaligned_access)) { 420 if (A->getOption().matches(options::OPT_mno_unaligned_access)) 421 Features.push_back("+strict-align"); 422 } else if (Triple.isOSOpenBSD()) 423 Features.push_back("+strict-align"); 424 425 if (Args.hasArg(options::OPT_ffixed_x1)) 426 Features.push_back("+reserve-x1"); 427 428 if (Args.hasArg(options::OPT_ffixed_x2)) 429 Features.push_back("+reserve-x2"); 430 431 if (Args.hasArg(options::OPT_ffixed_x3)) 432 Features.push_back("+reserve-x3"); 433 434 if (Args.hasArg(options::OPT_ffixed_x4)) 435 Features.push_back("+reserve-x4"); 436 437 if (Args.hasArg(options::OPT_ffixed_x5)) 438 Features.push_back("+reserve-x5"); 439 440 if (Args.hasArg(options::OPT_ffixed_x6)) 441 Features.push_back("+reserve-x6"); 442 443 if (Args.hasArg(options::OPT_ffixed_x7)) 444 Features.push_back("+reserve-x7"); 445 446 if (Args.hasArg(options::OPT_ffixed_x9)) 447 Features.push_back("+reserve-x9"); 448 449 if (Args.hasArg(options::OPT_ffixed_x10)) 450 Features.push_back("+reserve-x10"); 451 452 if (Args.hasArg(options::OPT_ffixed_x11)) 453 Features.push_back("+reserve-x11"); 454 455 if (Args.hasArg(options::OPT_ffixed_x12)) 456 Features.push_back("+reserve-x12"); 457 458 if (Args.hasArg(options::OPT_ffixed_x13)) 459 Features.push_back("+reserve-x13"); 460 461 if (Args.hasArg(options::OPT_ffixed_x14)) 462 Features.push_back("+reserve-x14"); 463 464 if (Args.hasArg(options::OPT_ffixed_x15)) 465 Features.push_back("+reserve-x15"); 466 467 if (Args.hasArg(options::OPT_ffixed_x18)) 468 Features.push_back("+reserve-x18"); 469 470 if (Args.hasArg(options::OPT_ffixed_x20)) 471 Features.push_back("+reserve-x20"); 472 473 if (Args.hasArg(options::OPT_ffixed_x21)) 474 Features.push_back("+reserve-x21"); 475 476 if (Args.hasArg(options::OPT_ffixed_x22)) 477 Features.push_back("+reserve-x22"); 478 479 if (Args.hasArg(options::OPT_ffixed_x23)) 480 Features.push_back("+reserve-x23"); 481 482 if (Args.hasArg(options::OPT_ffixed_x24)) 483 Features.push_back("+reserve-x24"); 484 485 if (Args.hasArg(options::OPT_ffixed_x25)) 486 Features.push_back("+reserve-x25"); 487 488 if (Args.hasArg(options::OPT_ffixed_x26)) 489 Features.push_back("+reserve-x26"); 490 491 if (Args.hasArg(options::OPT_ffixed_x27)) 492 Features.push_back("+reserve-x27"); 493 494 if (Args.hasArg(options::OPT_ffixed_x28)) 495 Features.push_back("+reserve-x28"); 496 497 if (Args.hasArg(options::OPT_ffixed_x30)) 498 Features.push_back("+reserve-x30"); 499 500 if (Args.hasArg(options::OPT_fcall_saved_x8)) 501 Features.push_back("+call-saved-x8"); 502 503 if (Args.hasArg(options::OPT_fcall_saved_x9)) 504 Features.push_back("+call-saved-x9"); 505 506 if (Args.hasArg(options::OPT_fcall_saved_x10)) 507 Features.push_back("+call-saved-x10"); 508 509 if (Args.hasArg(options::OPT_fcall_saved_x11)) 510 Features.push_back("+call-saved-x11"); 511 512 if (Args.hasArg(options::OPT_fcall_saved_x12)) 513 Features.push_back("+call-saved-x12"); 514 515 if (Args.hasArg(options::OPT_fcall_saved_x13)) 516 Features.push_back("+call-saved-x13"); 517 518 if (Args.hasArg(options::OPT_fcall_saved_x14)) 519 Features.push_back("+call-saved-x14"); 520 521 if (Args.hasArg(options::OPT_fcall_saved_x15)) 522 Features.push_back("+call-saved-x15"); 523 524 if (Args.hasArg(options::OPT_fcall_saved_x18)) 525 Features.push_back("+call-saved-x18"); 526 527 if (Args.hasArg(options::OPT_mno_neg_immediates)) 528 Features.push_back("+no-neg-immediates"); 529 } 530