clang 8.0.0

ARM.cpp
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1 //===--- ARM.cpp - ARM (not AArch64) Helpers for Tools ----------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "ARM.h"
11 #include "clang/Driver/Driver.h"
12 #include "clang/Driver/DriverDiagnostic.h"
13 #include "clang/Driver/Options.h"
14 #include "llvm/ADT/StringSwitch.h"
15 #include "llvm/Option/ArgList.h"
16 #include "llvm/Support/TargetParser.h"
17
18 using namespace clang::driver;
19 using namespace clang::driver::tools;
20 using namespace clang;
21 using namespace llvm::opt;
22
23 // Get SubArch (vN).
24 int arm::getARMSubArchVersionNumber(const llvm::Triple &Triple) {
25 llvm::StringRef Arch = Triple.getArchName();
26 return llvm::ARM::parseArchVersion(Arch);
27 }
28
29 // True if M-profile.
30 bool arm::isARMMProfile(const llvm::Triple &Triple) {
31 llvm::StringRef Arch = Triple.getArchName();
32 return llvm::ARM::parseArchProfile(Arch) == llvm::ARM::ProfileKind::M;
33 }
34
35 // Get Arch/CPU from args.
36 void arm::getARMArchCPUFromArgs(const ArgList &Args, llvm::StringRef &Arch,
37 llvm::StringRef &CPU, bool FromAs) {
38 if (const Arg *A = Args.getLastArg(clang::driver::options::OPT_mcpu_EQ))
39 CPU = A->getValue();
40 if (const Arg *A = Args.getLastArg(options::OPT_march_EQ))
41 Arch = A->getValue();
42 if (!FromAs)
43 return;
44
45 for (const Arg *A :
46 Args.filtered(options::OPT_Wa_COMMA, options::OPT_Xassembler)) {
47 StringRef Value = A->getValue();
48 if (Value.startswith("-mcpu="))
49 CPU = Value.substr(6);
50 if (Value.startswith("-march="))
51 Arch = Value.substr(7);
52 }
53 }
54
55 // Handle -mhwdiv=.
56 // FIXME: Use ARMTargetParser.
57 static void getARMHWDivFeatures(const Driver &D, const Arg *A,
58 const ArgList &Args, StringRef HWDiv,
59 std::vector<StringRef> &Features) {
60 unsigned HWDivID = llvm::ARM::parseHWDiv(HWDiv);
61 if (!llvm::ARM::getHWDivFeatures(HWDivID, Features))
62 D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args);
63 }
64
65 // Handle -mfpu=.
66 static void getARMFPUFeatures(const Driver &D, const Arg *A,
67 const ArgList &Args, StringRef FPU,
68 std::vector<StringRef> &Features) {
69 unsigned FPUID = llvm::ARM::parseFPU(FPU);
70 if (!llvm::ARM::getFPUFeatures(FPUID, Features))
71 D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args);
72 }
73
74 // Decode ARM features from string like +[no]featureA+[no]featureB+...
75 static bool DecodeARMFeatures(const Driver &D, StringRef text,
76 std::vector<StringRef> &Features) {
77 SmallVector<StringRef, 8> Split;
78 text.split(Split, StringRef("+"), -1, false);
79
80 for (StringRef Feature : Split) {
81 StringRef FeatureName = llvm::ARM::getArchExtFeature(Feature);
82 if (!FeatureName.empty())
83 Features.push_back(FeatureName);
84 else
85 return false;
86 }
87 return true;
88 }
89
90 static void DecodeARMFeaturesFromCPU(const Driver &D, StringRef CPU,
91 std::vector<StringRef> &Features) {
92 if (CPU != "generic") {
93 llvm::ARM::ArchKind ArchKind = llvm::ARM::parseCPUArch(CPU);
94 unsigned Extension = llvm::ARM::getDefaultExtensions(CPU, ArchKind);
95 llvm::ARM::getExtensionFeatures(Extension, Features);
96 }
97 }
98
99 // Check if -march is valid by checking if it can be canonicalised and parsed.
100 // getARMArch is used here instead of just checking the -march value in order
101 // to handle -march=native correctly.
102 static void checkARMArchName(const Driver &D, const Arg *A, const ArgList &Args,
103 llvm::StringRef ArchName,
104 std::vector<StringRef> &Features,
105 const llvm::Triple &Triple) {
106 std::pair<StringRef, StringRef> Split = ArchName.split("+");
107
108 std::string MArch = arm::getARMArch(ArchName, Triple);
109 if (llvm::ARM::parseArch(MArch) == llvm::ARM::ArchKind::INVALID ||
110 (Split.second.size() && !DecodeARMFeatures(D, Split.second, Features)))
111 D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args);
112 }
113
114 // Check -mcpu=. Needs ArchName to handle -mcpu=generic.
115 static void checkARMCPUName(const Driver &D, const Arg *A, const ArgList &Args,
116 llvm::StringRef CPUName, llvm::StringRef ArchName,
117 std::vector<StringRef> &Features,
118 const llvm::Triple &Triple) {
119 std::pair<StringRef, StringRef> Split = CPUName.split("+");
120
121 std::string CPU = arm::getARMTargetCPU(CPUName, ArchName, Triple);
122 if (arm::getLLVMArchSuffixForARM(CPU, ArchName, Triple).empty() ||
123 (Split.second.size() && !DecodeARMFeatures(D, Split.second, Features)))
124 D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args);
125 }
126
127 bool arm::useAAPCSForMachO(const llvm::Triple &T) {
128 // The backend is hardwired to assume AAPCS for M-class processors, ensure
129 // the frontend matches that.
130 return T.getEnvironment() == llvm::Triple::EABI ||
131 T.getOS() == llvm::Triple::UnknownOS || isARMMProfile(T);
132 }
133
134 // Select mode for reading thread pointer (-mtp=soft/cp15).
135 arm::ReadTPMode arm::getReadTPMode(const ToolChain &TC, const ArgList &Args) {
136 if (Arg *A = Args.getLastArg(options::OPT_mtp_mode_EQ)) {
137 const Driver &D = TC.getDriver();
138 arm::ReadTPMode ThreadPointer =
139 llvm::StringSwitch<arm::ReadTPMode>(A->getValue())
140 .Case("cp15", ReadTPMode::Cp15)
141 .Case("soft", ReadTPMode::Soft)
142 .Default(ReadTPMode::Invalid);
143 if (ThreadPointer != ReadTPMode::Invalid)
144 return ThreadPointer;
145 if (StringRef(A->getValue()).empty())
146 D.Diag(diag::err_drv_missing_arg_mtp) << A->getAsString(Args);
147 else
148 D.Diag(diag::err_drv_invalid_mtp) << A->getAsString(Args);
149 return ReadTPMode::Invalid;
150 }
151 return ReadTPMode::Soft;
152 }
153
154 // Select the float ABI as determined by -msoft-float, -mhard-float, and
155 // -mfloat-abi=.
156 arm::FloatABI arm::getARMFloatABI(const ToolChain &TC, const ArgList &Args) {
157 const Driver &D = TC.getDriver();
158 const llvm::Triple &Triple = TC.getEffectiveTriple();
159 auto SubArch = getARMSubArchVersionNumber(Triple);
160 arm::FloatABI ABI = FloatABI::Invalid;
161 if (Arg *A =
162 Args.getLastArg(options::OPT_msoft_float, options::OPT_mhard_float,
163 options::OPT_mfloat_abi_EQ)) {
164 if (A->getOption().matches(options::OPT_msoft_float)) {
165 ABI = FloatABI::Soft;
166 } else if (A->getOption().matches(options::OPT_mhard_float)) {
167 ABI = FloatABI::Hard;
168 } else {
169 ABI = llvm::StringSwitch<arm::FloatABI>(A->getValue())
170 .Case("soft", FloatABI::Soft)
171 .Case("softfp", FloatABI::SoftFP)
172 .Case("hard", FloatABI::Hard)
173 .Default(FloatABI::Invalid);
174 if (ABI == FloatABI::Invalid && !StringRef(A->getValue()).empty()) {
175 D.Diag(diag::err_drv_invalid_mfloat_abi) << A->getAsString(Args);
176 ABI = FloatABI::Soft;
177 }
178 }
179
180 // It is incorrect to select hard float ABI on MachO platforms if the ABI is
181 // "apcs-gnu".
182 if (Triple.isOSBinFormatMachO() && !useAAPCSForMachO(Triple) &&
183 ABI == FloatABI::Hard) {
184 D.Diag(diag::err_drv_unsupported_opt_for_target) << A->getAsString(Args)
185 << Triple.getArchName();
186 }
187 }
188
189 // If unspecified, choose the default based on the platform.
190 if (ABI == FloatABI::Invalid) {
191 switch (Triple.getOS()) {
192 case llvm::Triple::Darwin:
193 case llvm::Triple::MacOSX:
194 case llvm::Triple::IOS:
195 case llvm::Triple::TvOS: {
196 // Darwin defaults to "softfp" for v6 and v7.
197 ABI = (SubArch == 6 || SubArch == 7) ? FloatABI::SoftFP : FloatABI::Soft;
198 ABI = Triple.isWatchABI() ? FloatABI::Hard : ABI;
199 break;
200 }
201 case llvm::Triple::WatchOS:
202 ABI = FloatABI::Hard;
203 break;
204
205 // FIXME: this is invalid for WindowsCE
206 case llvm::Triple::Win32:
207 ABI = FloatABI::Hard;
208 break;
209
210 case llvm::Triple::NetBSD:
211 switch (Triple.getEnvironment()) {
212 case llvm::Triple::EABIHF:
213 case llvm::Triple::GNUEABIHF:
214 ABI = FloatABI::Hard;
215 break;
216 default:
217 ABI = FloatABI::Soft;
218 break;
219 }
220 break;
221
222 case llvm::Triple::FreeBSD:
223 switch (Triple.getEnvironment()) {
224 case llvm::Triple::GNUEABIHF:
225 ABI = FloatABI::Hard;
226 break;
227 default:
228 // FreeBSD defaults to soft float
229 ABI = FloatABI::Soft;
230 break;
231 }
232 break;
233
234 case llvm::Triple::OpenBSD:
235 ABI = FloatABI::SoftFP;
236 break;
237
238 default:
239 switch (Triple.getEnvironment()) {
240 case llvm::Triple::GNUEABIHF:
241 case llvm::Triple::MuslEABIHF:
242 case llvm::Triple::EABIHF:
243 ABI = FloatABI::Hard;
244 break;
245 case llvm::Triple::GNUEABI:
246 case llvm::Triple::MuslEABI:
247 case llvm::Triple::EABI:
248 // EABI is always AAPCS, and if it was not marked 'hard', it's softfp
249 ABI = FloatABI::SoftFP;
250 break;
251 case llvm::Triple::Android:
252 ABI = (SubArch == 7) ? FloatABI::SoftFP : FloatABI::Soft;
253 break;
254 default:
255 // Assume "soft", but warn the user we are guessing.
256 if (Triple.isOSBinFormatMachO() &&
257 Triple.getSubArch() == llvm::Triple::ARMSubArch_v7em)
258 ABI = FloatABI::Hard;
259 else
260 ABI = FloatABI::Soft;
261
262 if (Triple.getOS() != llvm::Triple::UnknownOS ||
263 !Triple.isOSBinFormatMachO())
264 D.Diag(diag::warn_drv_assuming_mfloat_abi_is) << "soft";
265 break;
266 }
267 }
268 }
269
270 assert(ABI != FloatABI::Invalid && "must select an ABI");
271 return ABI;
272 }
273
274 void arm::getARMTargetFeatures(const ToolChain &TC,
275 const llvm::Triple &Triple,
276 const ArgList &Args,
277 ArgStringList &CmdArgs,
278 std::vector<StringRef> &Features,
279 bool ForAS) {
280 const Driver &D = TC.getDriver();
281
282 bool KernelOrKext =
283 Args.hasArg(options::OPT_mkernel, options::OPT_fapple_kext);
284 arm::FloatABI ABI = arm::getARMFloatABI(TC, Args);
285 arm::ReadTPMode ThreadPointer = arm::getReadTPMode(TC, Args);
286 const Arg *WaCPU = nullptr, *WaFPU = nullptr;
287 const Arg *WaHDiv = nullptr, *WaArch = nullptr;
288
289 if (!ForAS) {
290 // FIXME: Note, this is a hack, the LLVM backend doesn't actually use these
291 // yet (it uses the -mfloat-abi and -msoft-float options), and it is
292 // stripped out by the ARM target. We should probably pass this a new
293 // -target-option, which is handled by the -cc1/-cc1as invocation.
294 //
295 // FIXME2: For consistency, it would be ideal if we set up the target
296 // machine state the same when using the frontend or the assembler. We don't
297 // currently do that for the assembler, we pass the options directly to the
298 // backend and never even instantiate the frontend TargetInfo. If we did,
299 // and used its handleTargetFeatures hook, then we could ensure the
300 // assembler and the frontend behave the same.
301
302 // Use software floating point operations?
303 if (ABI == arm::FloatABI::Soft)
304 Features.push_back("+soft-float");
305
306 // Use software floating point argument passing?
307 if (ABI != arm::FloatABI::Hard)
308 Features.push_back("+soft-float-abi");
309 } else {
310 // Here, we make sure that -Wa,-mfpu/cpu/arch/hwdiv will be passed down
311 // to the assembler correctly.
312 for (const Arg *A :
313 Args.filtered(options::OPT_Wa_COMMA, options::OPT_Xassembler)) {
314 StringRef Value = A->getValue();
315 if (Value.startswith("-mfpu=")) {
316 WaFPU = A;
317 } else if (Value.startswith("-mcpu=")) {
318 WaCPU = A;
319 } else if (Value.startswith("-mhwdiv=")) {
320 WaHDiv = A;
321 } else if (Value.startswith("-march=")) {
322 WaArch = A;
323 }
324 }
325 }
326
327 if (ThreadPointer == arm::ReadTPMode::Cp15)
328 Features.push_back("+read-tp-hard");
329
330 // Check -march. ClangAs gives preference to -Wa,-march=.
331 const Arg *ArchArg = Args.getLastArg(options::OPT_march_EQ);
332 StringRef ArchName;
333 if (WaArch) {
334 if (ArchArg)
335 D.Diag(clang::diag::warn_drv_unused_argument)
336 << ArchArg->getAsString(Args);
337 ArchName = StringRef(WaArch->getValue()).substr(7);
338 checkARMArchName(D, WaArch, Args, ArchName, Features, Triple);
339 // FIXME: Set Arch.
340 D.Diag(clang::diag::warn_drv_unused_argument) << WaArch->getAsString(Args);
341 } else if (ArchArg) {
342 ArchName = ArchArg->getValue();
343 checkARMArchName(D, ArchArg, Args, ArchName, Features, Triple);
344 }
345
346 // Check -mcpu. ClangAs gives preference to -Wa,-mcpu=.
347 const Arg *CPUArg = Args.getLastArg(options::OPT_mcpu_EQ);
348 StringRef CPUName;
349 if (WaCPU) {
350 if (CPUArg)
351 D.Diag(clang::diag::warn_drv_unused_argument)
352 << CPUArg->getAsString(Args);
353 CPUName = StringRef(WaCPU->getValue()).substr(6);
354 checkARMCPUName(D, WaCPU, Args, CPUName, ArchName, Features, Triple);
355 } else if (CPUArg) {
356 CPUName = CPUArg->getValue();
357 checkARMCPUName(D, CPUArg, Args, CPUName, ArchName, Features, Triple);
358 }
359
360 // Add CPU features for generic CPUs
361 if (CPUName == "native") {
362 llvm::StringMap<bool> HostFeatures;
363 if (llvm::sys::getHostCPUFeatures(HostFeatures))
364 for (auto &F : HostFeatures)
365 Features.push_back(
366 Args.MakeArgString((F.second ? "+" : "-") + F.first()));
367 } else if (!CPUName.empty()) {
368 DecodeARMFeaturesFromCPU(D, CPUName, Features);
369 }
370
371 // Honor -mfpu=. ClangAs gives preference to -Wa,-mfpu=.
372 const Arg *FPUArg = Args.getLastArg(options::OPT_mfpu_EQ);
373 if (WaFPU) {
374 if (FPUArg)
375 D.Diag(clang::diag::warn_drv_unused_argument)
376 << FPUArg->getAsString(Args);
377 getARMFPUFeatures(D, WaFPU, Args, StringRef(WaFPU->getValue()).substr(6),
378 Features);
379 } else if (FPUArg) {
380 getARMFPUFeatures(D, FPUArg, Args, FPUArg->getValue(), Features);
381 } else if (Triple.isAndroid() && getARMSubArchVersionNumber(Triple) >= 7) {
382 // Android mandates minimum FPU requirements based on OS version.
383 const char *AndroidFPU =
384 Triple.isAndroidVersionLT(23) ? "vfpv3-d16" : "neon";
385 if (!llvm::ARM::getFPUFeatures(llvm::ARM::parseFPU(AndroidFPU), Features))
386 D.Diag(clang::diag::err_drv_clang_unsupported)
387 << std::string("-mfpu=") + AndroidFPU;
388 }
389
390 // Honor -mhwdiv=. ClangAs gives preference to -Wa,-mhwdiv=.
391 const Arg *HDivArg = Args.getLastArg(options::OPT_mhwdiv_EQ);
392 if (WaHDiv) {
393 if (HDivArg)
394 D.Diag(clang::diag::warn_drv_unused_argument)
395 << HDivArg->getAsString(Args);
396 getARMHWDivFeatures(D, WaHDiv, Args,
397 StringRef(WaHDiv->getValue()).substr(8), Features);
398 } else if (HDivArg)
399 getARMHWDivFeatures(D, HDivArg, Args, HDivArg->getValue(), Features);
400
401 // Handle (arch-dependent) fp16fml/fullfp16 relationship.
402 // Must happen before any features are disabled due to soft-float.
403 // FIXME: this fp16fml option handling will be reimplemented after the
404 // TargetParser rewrite.
405 const auto ItRNoFullFP16 = std::find(Features.rbegin(), Features.rend(), "-fullfp16");
406 const auto ItRFP16FML = std::find(Features.rbegin(), Features.rend(), "+fp16fml");
407 if (Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v8_4a) {
408 const auto ItRFullFP16 = std::find(Features.rbegin(), Features.rend(), "+fullfp16");
409 if (ItRFullFP16 < ItRNoFullFP16 && ItRFullFP16 < ItRFP16FML) {
410 // Only entangled feature that can be to the right of this +fullfp16 is -fp16fml.
411 // Only append the +fp16fml if there is no -fp16fml after the +fullfp16.
412 if (std::find(Features.rbegin(), ItRFullFP16, "-fp16fml") == ItRFullFP16)
413 Features.push_back("+fp16fml");
414 }
415 else
416 goto fp16_fml_fallthrough;
417 }
418 else {
419 fp16_fml_fallthrough:
420 // In both of these cases, putting the 'other' feature on the end of the vector will
421 // result in the same effect as placing it immediately after the current feature.
422 if (ItRNoFullFP16 < ItRFP16FML)
423 Features.push_back("-fp16fml");
424 else if (ItRNoFullFP16 > ItRFP16FML)
425 Features.push_back("+fullfp16");
426 }
427
428 // Setting -msoft-float/-mfloat-abi=soft effectively disables the FPU (GCC
429 // ignores the -mfpu options in this case).
430 // Note that the ABI can also be set implicitly by the target selected.
431 if (ABI == arm::FloatABI::Soft) {
432 llvm::ARM::getFPUFeatures(llvm::ARM::FK_NONE, Features);
433
434 // Disable hardware FP features which have been enabled.
435 // FIXME: Disabling vfp2 and neon should be enough as all the other
436 // features are dependent on these 2 features in LLVM. However
437 // there is currently no easy way to test this in clang, so for
438 // now just be explicit and disable all known dependent features
439 // as well.
440 for (std::string Feature : {"vfp2", "vfp3", "vfp4", "fp-armv8", "fullfp16",
441 "neon", "crypto", "dotprod", "fp16fml"})
442 if (std::find(std::begin(Features), std::end(Features), "+" + Feature) != std::end(Features))
443 Features.push_back(Args.MakeArgString("-" + Feature));
444 }
445
446 // En/disable crc code generation.
447 if (Arg *A = Args.getLastArg(options::OPT_mcrc, options::OPT_mnocrc)) {
448 if (A->getOption().matches(options::OPT_mcrc))
449 Features.push_back("+crc");
450 else
451 Features.push_back("-crc");
452 }
453
454 // For Arch >= ARMv8.0: crypto = sha2 + aes
455 // FIXME: this needs reimplementation after the TargetParser rewrite
456 if (ArchName.find_lower("armv8a") != StringRef::npos ||
457 ArchName.find_lower("armv8.1a") != StringRef::npos ||
458 ArchName.find_lower("armv8.2a") != StringRef::npos ||
459 ArchName.find_lower("armv8.3a") != StringRef::npos ||
460 ArchName.find_lower("armv8.4a") != StringRef::npos) {
461 if (ArchName.find_lower("+crypto") != StringRef::npos) {
462 if (ArchName.find_lower("+nosha2") == StringRef::npos)
463 Features.push_back("+sha2");
464 if (ArchName.find_lower("+noaes") == StringRef::npos)
465 Features.push_back("+aes");
466 } else if (ArchName.find_lower("-crypto") != StringRef::npos) {
467 if (ArchName.find_lower("+sha2") == StringRef::npos)
468 Features.push_back("-sha2");
469 if (ArchName.find_lower("+aes") == StringRef::npos)
470 Features.push_back("-aes");
471 }
472 }
473
474 // Look for the last occurrence of -mlong-calls or -mno-long-calls. If
475 // neither options are specified, see if we are compiling for kernel/kext and
476 // decide whether to pass "+long-calls" based on the OS and its version.
477 if (Arg *A = Args.getLastArg(options::OPT_mlong_calls,
478 options::OPT_mno_long_calls)) {
479 if (A->getOption().matches(options::OPT_mlong_calls))
480 Features.push_back("+long-calls");
481 } else if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6)) &&
482 !Triple.isWatchOS()) {
483 Features.push_back("+long-calls");
484 }
485
486 // Generate execute-only output (no data access to code sections).
487 // This only makes sense for the compiler, not for the assembler.
488 if (!ForAS) {
489 // Supported only on ARMv6T2 and ARMv7 and above.
490 // Cannot be combined with -mno-movt or -mlong-calls
491 if (Arg *A = Args.getLastArg(options::OPT_mexecute_only, options::OPT_mno_execute_only)) {
492 if (A->getOption().matches(options::OPT_mexecute_only)) {
493 if (getARMSubArchVersionNumber(Triple) < 7 &&
494 llvm::ARM::parseArch(Triple.getArchName()) != llvm::ARM::ArchKind::ARMV6T2)
495 D.Diag(diag::err_target_unsupported_execute_only) << Triple.getArchName();
496 else if (Arg *B = Args.getLastArg(options::OPT_mno_movt))
497 D.Diag(diag::err_opt_not_valid_with_opt) << A->getAsString(Args) << B->getAsString(Args);
498 // Long calls create constant pool entries and have not yet been fixed up
499 // to play nicely with execute-only. Hence, they cannot be used in
500 // execute-only code for now
501 else if (Arg *B = Args.getLastArg(options::OPT_mlong_calls, options::OPT_mno_long_calls)) {
502 if (B->getOption().matches(options::OPT_mlong_calls))
503 D.Diag(diag::err_opt_not_valid_with_opt) << A->getAsString(Args) << B->getAsString(Args);
504 }
505 Features.push_back("+execute-only");
506 }
507 }
508 }
509
510 // Kernel code has more strict alignment requirements.
511 if (KernelOrKext)
512 Features.push_back("+strict-align");
513 else if (Arg *A = Args.getLastArg(options::OPT_mno_unaligned_access,
514 options::OPT_munaligned_access)) {
515 if (A->getOption().matches(options::OPT_munaligned_access)) {
516 // No v6M core supports unaligned memory access (v6M ARM ARM A3.2).
517 if (Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v6m)
518 D.Diag(diag::err_target_unsupported_unaligned) << "v6m";
519 // v8M Baseline follows on from v6M, so doesn't support unaligned memory
520 // access either.
521 else if (Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v8m_baseline)
522 D.Diag(diag::err_target_unsupported_unaligned) << "v8m.base";
523 } else
524 Features.push_back("+strict-align");
525 } else {
526 // Assume pre-ARMv6 doesn't support unaligned accesses.
527 //
528 // ARMv6 may or may not support unaligned accesses depending on the
529 // SCTLR.U bit, which is architecture-specific. We assume ARMv6
530 // Darwin and NetBSD targets support unaligned accesses, and others don't.
531 //
532 // ARMv7 always has SCTLR.U set to 1, but it has a new SCTLR.A bit
533 // which raises an alignment fault on unaligned accesses. Linux
534 // defaults this bit to 0 and handles it as a system-wide (not
535 // per-process) setting. It is therefore safe to assume that ARMv7+
536 // Linux targets support unaligned accesses. The same goes for NaCl.
537 //
538 // The above behavior is consistent with GCC.
539 int VersionNum = getARMSubArchVersionNumber(Triple);
540 if (Triple.isOSDarwin() || Triple.isOSNetBSD()) {
541 if (VersionNum < 6 ||
542 Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v6m)
543 Features.push_back("+strict-align");
544 } else if (Triple.isOSLinux() || Triple.isOSNaCl()) {
545 if (VersionNum < 7)
546 Features.push_back("+strict-align");
547 } else
548 Features.push_back("+strict-align");
549 }
550
551 // llvm does not support reserving registers in general. There is support
552 // for reserving r9 on ARM though (defined as a platform-specific register
553 // in ARM EABI).
554 if (Args.hasArg(options::OPT_ffixed_r9))
555 Features.push_back("+reserve-r9");
556
557 // The kext linker doesn't know how to deal with movw/movt.
558 if (KernelOrKext || Args.hasArg(options::OPT_mno_movt))
559 Features.push_back("+no-movt");
560
561 if (Args.hasArg(options::OPT_mno_neg_immediates))
562 Features.push_back("+no-neg-immediates");
563 }
564
565 const std::string arm::getARMArch(StringRef Arch, const llvm::Triple &Triple) {
566 std::string MArch;
567 if (!Arch.empty())
568 MArch = Arch;
569 else
570 MArch = Triple.getArchName();
571 MArch = StringRef(MArch).split("+").first.lower();
572
573 // Handle -march=native.
574 if (MArch == "native") {
575 std::string CPU = llvm::sys::getHostCPUName();
576 if (CPU != "generic") {
577 // Translate the native cpu into the architecture suffix for that CPU.
578 StringRef Suffix = arm::getLLVMArchSuffixForARM(CPU, MArch, Triple);
579 // If there is no valid architecture suffix for this CPU we don't know how
580 // to handle it, so return no architecture.
581 if (Suffix.empty())
582 MArch = "";
583 else
584 MArch = std::string("arm") + Suffix.str();
585 }
586 }
587
588 return MArch;
589 }
590
591 /// Get the (LLVM) name of the minimum ARM CPU for the arch we are targeting.
592 StringRef arm::getARMCPUForMArch(StringRef Arch, const llvm::Triple &Triple) {
593 std::string MArch = getARMArch(Arch, Triple);
594 // getARMCPUForArch defaults to the triple if MArch is empty, but empty MArch
595 // here means an -march=native that we can't handle, so instead return no CPU.
596 if (MArch.empty())
597 return StringRef();
598
599 // We need to return an empty string here on invalid MArch values as the
600 // various places that call this function can't cope with a null result.
601 return Triple.getARMCPUForArch(MArch);
602 }
603
604 /// getARMTargetCPU - Get the (LLVM) name of the ARM cpu we are targeting.
605 std::string arm::getARMTargetCPU(StringRef CPU, StringRef Arch,
606 const llvm::Triple &Triple) {
607 // FIXME: Warn on inconsistent use of -mcpu and -march.
608 // If we have -mcpu=, use that.
609 if (!CPU.empty()) {
610 std::string MCPU = StringRef(CPU).split("+").first.lower();
611 // Handle -mcpu=native.
612 if (MCPU == "native")
613 return llvm::sys::getHostCPUName();
614 else
615 return MCPU;
616 }
617
618 return getARMCPUForMArch(Arch, Triple);
619 }
620
621 /// getLLVMArchSuffixForARM - Get the LLVM arch name to use for a particular
622 /// CPU (or Arch, if CPU is generic).
623 // FIXME: This is redundant with -mcpu, why does LLVM use this.
624 StringRef arm::getLLVMArchSuffixForARM(StringRef CPU, StringRef Arch,
625 const llvm::Triple &Triple) {
626 llvm::ARM::ArchKind ArchKind;
627 if (CPU == "generic") {
628 std::string ARMArch = tools::arm::getARMArch(Arch, Triple);
629 ArchKind = llvm::ARM::parseArch(ARMArch);
630 if (ArchKind == llvm::ARM::ArchKind::INVALID)
631 // In case of generic Arch, i.e. "arm",
632 // extract arch from default cpu of the Triple
633 ArchKind = llvm::ARM::parseCPUArch(Triple.getARMCPUForArch(ARMArch));
634 } else {
635 // FIXME: horrible hack to get around the fact that Cortex-A7 is only an
636 // armv7k triple if it's actually been specified via "-arch armv7k".
637 ArchKind = (Arch == "armv7k" || Arch == "thumbv7k")
638 ? llvm::ARM::ArchKind::ARMV7K
639 : llvm::ARM::parseCPUArch(CPU);
640 }
641 if (ArchKind == llvm::ARM::ArchKind::INVALID)
642 return "";
643 return llvm::ARM::getSubArch(ArchKind);
644 }
645
646 void arm::appendBE8LinkFlag(const ArgList &Args, ArgStringList &CmdArgs,
647 const llvm::Triple &Triple) {
648 if (Args.hasArg(options::OPT_r))
649 return;
650
651 // ARMv7 (and later) and ARMv6-M do not support BE-32, so instruct the linker
652 // to generate BE-8 executables.
653 if (arm::getARMSubArchVersionNumber(Triple) >= 7 || arm::isARMMProfile(Triple))
654 CmdArgs.push_back("--be8");
655 }
clang::driver::tools::arm::useAAPCSForMachO
bool useAAPCSForMachO(const llvm::Triple &T)
Definition: ARM.cpp:127
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DiagnosticBuilder Diag(unsigned DiagID) const
Definition: Driver.h:109
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Value
Definition: UninitializedValues.cpp:102
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static void getExtensionFeatures(const Driver &D, const ArgList &Args, std::vector< StringRef > &Features, StringRef &MArch, StringRef &Exts)
Definition: RISCV.cpp:102
clang::driver::tools::arm::getARMFloatABI
FloatABI getARMFloatABI(const ToolChain &TC, const llvm::opt::ArgList &Args)
checkARMArchName
static void checkARMArchName(const Driver &D, const Arg *A, const ArgList &Args, llvm::StringRef ArchName, std::vector< StringRef > &Features, const llvm::Triple &Triple)
Definition: ARM.cpp:102
clang::driver::tools::arm::getARMArch
const std::string getARMArch(llvm::StringRef Arch, const llvm::Triple &Triple)
DecodeARMFeaturesFromCPU
static void DecodeARMFeaturesFromCPU(const Driver &D, StringRef CPU, std::vector< StringRef > &Features)
Definition: ARM.cpp:90
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bool isARMMProfile(const llvm::Triple &Triple)
Definition: ARM.cpp:30
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Definition: AMDGPU.h:21
clang::driver::tools::arm::getARMCPUForMArch
StringRef getARMCPUForMArch(llvm::StringRef Arch, const llvm::Triple &Triple)
clang::driver::Driver
Driver - Encapsulate logic for constructing compilation processes from a set of gcc-driver-like comma...
Definition: Driver.h:58
ARM.h
clang::driver::tools::arm::FloatABI
FloatABI
Definition: ARM.h:41
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static bool DecodeARMFeatures(const Driver &D, StringRef text, std::vector< StringRef > &Features)
Definition: ARM.cpp:75
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clang::driver::tools::arm::FloatABI::Hard
llvm::opt
Definition: Action.h:24
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const llvm::Triple & getEffectiveTriple() const
Get the toolchain&#39;s effective clang triple.
Definition: ToolChain.h:216
clang::driver::tools::arm::getARMSubArchVersionNumber
int getARMSubArchVersionNumber(const llvm::Triple &Triple)
Definition: ARM.cpp:24
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static void getARMFPUFeatures(const Driver &D, const Arg *A, const ArgList &Args, StringRef FPU, std::vector< StringRef > &Features)
Definition: ARM.cpp:66
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const Driver & getDriver() const
Definition: ToolChain.h:186
llvm::SmallVector
Definition: LLVM.h:36
Options.h
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clang::driver::tools::arm::getARMTargetCPU
std::string getARMTargetCPU(StringRef CPU, llvm::StringRef Arch, const llvm::Triple &Triple)
clang
Dataflow Directional Tag Classes.
Definition: CFGReachabilityAnalysis.h:22
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Definition: CommentLexer.h:36
clang::driver::tools::arm::ReadTPMode::Cp15
clang::driver::tools::arm::getARMArchCPUFromArgs
void getARMArchCPUFromArgs(const llvm::opt::ArgList &Args, llvm::StringRef &Arch, llvm::StringRef &CPU, bool FromAs=false)
getARMHWDivFeatures
static void getARMHWDivFeatures(const Driver &D, const Arg *A, const ArgList &Args, StringRef HWDiv, std::vector< StringRef > &Features)
Definition: ARM.cpp:57
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Definition: Action.h:32
DriverDiagnostic.h
clang::driver::tools::arm::appendBE8LinkFlag
void appendBE8LinkFlag(const llvm::opt::ArgList &Args, llvm::opt::ArgStringList &CmdArgs, const llvm::Triple &Triple)
clang::driver::tools::arm::getReadTPMode
ReadTPMode getReadTPMode(const ToolChain &TC, const llvm::opt::ArgList &Args)
checkARMCPUName
static void checkARMCPUName(const Driver &D, const Arg *A, const ArgList &Args, llvm::StringRef CPUName, llvm::StringRef ArchName, std::vector< StringRef > &Features, const llvm::Triple &Triple)
Definition: ARM.cpp:115
clang::driver::tools::arm::getARMTargetFeatures
void getARMTargetFeatures(const ToolChain &TC, const llvm::Triple &Triple, const llvm::opt::ArgList &Args, llvm::opt::ArgStringList &CmdArgs, std::vector< llvm::StringRef > &Features, bool ForAS)
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StringRef getLLVMArchSuffixForARM(llvm::StringRef CPU, llvm::StringRef Arch, const llvm::Triple &Triple)
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Definition: ARM.h:35
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ToolChain - Access to tools for a single platform.
Definition: ToolChain.h:89