1 //===-- TargetParser - Parser for target features ---------------*- 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 // This file implements a target parser to recognise hardware features such as
11 // FPU/CPU/ARCH names as well as specific support such as HDIV, etc.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/Support/ARMBuildAttributes.h"
16 #include "llvm/Support/TargetParser.h"
17 #include "llvm/ADT/StringExtras.h"
18 #include "llvm/ADT/StringSwitch.h"
19 #include "llvm/ADT/Twine.h"
20 #include <cctype>
21 
22 using namespace llvm;
23 using namespace ARM;
24 using namespace AArch64;
25 
26 namespace {
27 
28 // List of canonical FPU names (use getFPUSynonym) and which architectural
29 // features they correspond to (use getFPUFeatures).
30 // FIXME: TableGen this.
31 // The entries must appear in the order listed in ARM::FPUKind for correct indexing
32 static const struct {
33   const char *NameCStr;
34   size_t NameLength;
35   ARM::FPUKind ID;
36   ARM::FPUVersion FPUVersion;
37   ARM::NeonSupportLevel NeonSupport;
38   ARM::FPURestriction Restriction;
39 
40   StringRef getName() const { return StringRef(NameCStr, NameLength); }
41 } FPUNames[] = {
42 #define ARM_FPU(NAME, KIND, VERSION, NEON_SUPPORT, RESTRICTION) \
43   { NAME, sizeof(NAME) - 1, KIND, VERSION, NEON_SUPPORT, RESTRICTION },
44 #include "llvm/Support/ARMTargetParser.def"
45 };
46 
47 // List of canonical arch names (use getArchSynonym).
48 // This table also provides the build attribute fields for CPU arch
49 // and Arch ID, according to the Addenda to the ARM ABI, chapters
50 // 2.4 and 2.3.5.2 respectively.
51 // FIXME: SubArch values were simplified to fit into the expectations
52 // of the triples and are not conforming with their official names.
53 // Check to see if the expectation should be changed.
54 // FIXME: TableGen this.
55 static const struct {
56   const char *NameCStr;
57   size_t NameLength;
58   const char *CPUAttrCStr;
59   size_t CPUAttrLength;
60   const char *SubArchCStr;
61   size_t SubArchLength;
62   unsigned DefaultFPU;
63   unsigned ArchBaseExtensions;
64   ARM::ArchKind ID;
65   ARMBuildAttrs::CPUArch ArchAttr; // Arch ID in build attributes.
66 
67   StringRef getName() const { return StringRef(NameCStr, NameLength); }
68 
69   // CPU class in build attributes.
70   StringRef getCPUAttr() const { return StringRef(CPUAttrCStr, CPUAttrLength); }
71 
72   // Sub-Arch name.
73   StringRef getSubArch() const { return StringRef(SubArchCStr, SubArchLength); }
74 } ARCHNames[] = {
75 #define ARM_ARCH(NAME, ID, CPU_ATTR, SUB_ARCH, ARCH_ATTR, ARCH_FPU, ARCH_BASE_EXT)       \
76   {NAME, sizeof(NAME) - 1, CPU_ATTR, sizeof(CPU_ATTR) - 1, SUB_ARCH,       \
77    sizeof(SUB_ARCH) - 1, ARCH_FPU, ARCH_BASE_EXT, ID, ARCH_ATTR},
78 #include "llvm/Support/ARMTargetParser.def"
79 },AArch64ARCHNames[] = {
80 #define AARCH64_ARCH(NAME, ID, CPU_ATTR, SUB_ARCH, ARCH_ATTR, ARCH_FPU, ARCH_BASE_EXT)       \
81   {NAME, sizeof(NAME) - 1, CPU_ATTR, sizeof(CPU_ATTR) - 1, SUB_ARCH,       \
82    sizeof(SUB_ARCH) - 1, ARCH_FPU, ARCH_BASE_EXT, ID, ARCH_ATTR},
83 #include "llvm/Support/AArch64TargetParser.def"
84 };
85 
86 // List of Arch Extension names.
87 // FIXME: TableGen this.
88 static const struct {
89   const char *NameCStr;
90   size_t NameLength;
91   unsigned ID;
92   const char *Feature;
93   const char *NegFeature;
94 
95   StringRef getName() const { return StringRef(NameCStr, NameLength); }
96 } ARCHExtNames[] = {
97 #define ARM_ARCH_EXT_NAME(NAME, ID, FEATURE, NEGFEATURE) \
98   { NAME, sizeof(NAME) - 1, ID, FEATURE, NEGFEATURE },
99 #include "llvm/Support/ARMTargetParser.def"
100 },AArch64ARCHExtNames[] = {
101 #define AARCH64_ARCH_EXT_NAME(NAME, ID, FEATURE, NEGFEATURE) \
102   { NAME, sizeof(NAME) - 1, ID, FEATURE, NEGFEATURE },
103 #include "llvm/Support/AArch64TargetParser.def"
104 };
105 
106 // List of HWDiv names (use getHWDivSynonym) and which architectural
107 // features they correspond to (use getHWDivFeatures).
108 // FIXME: TableGen this.
109 static const struct {
110   const char *NameCStr;
111   size_t NameLength;
112   unsigned ID;
113 
114   StringRef getName() const { return StringRef(NameCStr, NameLength); }
115 } HWDivNames[] = {
116 #define ARM_HW_DIV_NAME(NAME, ID) { NAME, sizeof(NAME) - 1, ID },
117 #include "llvm/Support/ARMTargetParser.def"
118 };
119 
120 // List of CPU names and their arches.
121 // The same CPU can have multiple arches and can be default on multiple arches.
122 // When finding the Arch for a CPU, first-found prevails. Sort them accordingly.
123 // When this becomes table-generated, we'd probably need two tables.
124 // FIXME: TableGen this.
125 static const struct {
126   const char *NameCStr;
127   size_t NameLength;
128   ARM::ArchKind ArchID;
129   bool Default; // is $Name the default CPU for $ArchID ?
130   unsigned DefaultExtensions;
131 
132   StringRef getName() const { return StringRef(NameCStr, NameLength); }
133 } CPUNames[] = {
134 #define ARM_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT) \
135   { NAME, sizeof(NAME) - 1, ID, IS_DEFAULT, DEFAULT_EXT },
136 #include "llvm/Support/ARMTargetParser.def"
137 },AArch64CPUNames[] = {
138 #define AARCH64_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT) \
139   { NAME, sizeof(NAME) - 1, ID, IS_DEFAULT, DEFAULT_EXT },
140 #include "llvm/Support/AArch64TargetParser.def"
141 };
142 
143 } // namespace
144 
145 // ======================================================= //
146 // Information by ID
147 // ======================================================= //
148 
149 StringRef llvm::ARM::getFPUName(unsigned FPUKind) {
150   if (FPUKind >= ARM::FK_LAST)
151     return StringRef();
152   return FPUNames[FPUKind].getName();
153 }
154 
155 unsigned llvm::ARM::getFPUVersion(unsigned FPUKind) {
156   if (FPUKind >= ARM::FK_LAST)
157     return 0;
158   return FPUNames[FPUKind].FPUVersion;
159 }
160 
161 unsigned llvm::ARM::getFPUNeonSupportLevel(unsigned FPUKind) {
162   if (FPUKind >= ARM::FK_LAST)
163     return 0;
164   return FPUNames[FPUKind].NeonSupport;
165 }
166 
167 unsigned llvm::ARM::getFPURestriction(unsigned FPUKind) {
168   if (FPUKind >= ARM::FK_LAST)
169     return 0;
170   return FPUNames[FPUKind].Restriction;
171 }
172 
173 unsigned llvm::ARM::getDefaultFPU(StringRef CPU, unsigned ArchKind) {
174   if (CPU == "generic")
175     return ARCHNames[ArchKind].DefaultFPU;
176 
177   return StringSwitch<unsigned>(CPU)
178 #define ARM_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT) \
179     .Case(NAME, DEFAULT_FPU)
180 #include "llvm/Support/ARMTargetParser.def"
181     .Default(ARM::FK_INVALID);
182 }
183 
184 unsigned llvm::ARM::getDefaultExtensions(StringRef CPU, unsigned ArchKind) {
185   if (CPU == "generic")
186     return ARCHNames[ArchKind].ArchBaseExtensions;
187 
188   return StringSwitch<unsigned>(CPU)
189 #define ARM_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT) \
190     .Case(NAME, ARCHNames[ID].ArchBaseExtensions | DEFAULT_EXT)
191 #include "llvm/Support/ARMTargetParser.def"
192     .Default(ARM::AEK_INVALID);
193 }
194 
195 bool llvm::ARM::getHWDivFeatures(unsigned HWDivKind,
196                                  std::vector<const char *> &Features) {
197 
198   if (HWDivKind == ARM::AEK_INVALID)
199     return false;
200 
201   if (HWDivKind & ARM::AEK_HWDIVARM)
202     Features.push_back("+hwdiv-arm");
203   else
204     Features.push_back("-hwdiv-arm");
205 
206   if (HWDivKind & ARM::AEK_HWDIV)
207     Features.push_back("+hwdiv");
208   else
209     Features.push_back("-hwdiv");
210 
211   return true;
212 }
213 
214 bool llvm::ARM::getExtensionFeatures(unsigned Extensions,
215                                      std::vector<const char *> &Features) {
216 
217   if (Extensions == ARM::AEK_INVALID)
218     return false;
219 
220   if (Extensions & ARM::AEK_CRC)
221     Features.push_back("+crc");
222   else
223     Features.push_back("-crc");
224 
225   if (Extensions & ARM::AEK_DSP)
226     Features.push_back("+dsp");
227   else
228     Features.push_back("-dsp");
229 
230   return getHWDivFeatures(Extensions, Features);
231 }
232 
233 bool llvm::ARM::getFPUFeatures(unsigned FPUKind,
234                                std::vector<const char *> &Features) {
235 
236   if (FPUKind >= ARM::FK_LAST || FPUKind == ARM::FK_INVALID)
237     return false;
238 
239   // fp-only-sp and d16 subtarget features are independent of each other, so we
240   // must enable/disable both.
241   switch (FPUNames[FPUKind].Restriction) {
242   case ARM::FR_SP_D16:
243     Features.push_back("+fp-only-sp");
244     Features.push_back("+d16");
245     break;
246   case ARM::FR_D16:
247     Features.push_back("-fp-only-sp");
248     Features.push_back("+d16");
249     break;
250   case ARM::FR_None:
251     Features.push_back("-fp-only-sp");
252     Features.push_back("-d16");
253     break;
254   }
255 
256   // FPU version subtarget features are inclusive of lower-numbered ones, so
257   // enable the one corresponding to this version and disable all that are
258   // higher. We also have to make sure to disable fp16 when vfp4 is disabled,
259   // as +vfp4 implies +fp16 but -vfp4 does not imply -fp16.
260   switch (FPUNames[FPUKind].FPUVersion) {
261   case ARM::FV_VFPV5:
262     Features.push_back("+fp-armv8");
263     break;
264   case ARM::FV_VFPV4:
265     Features.push_back("+vfp4");
266     Features.push_back("-fp-armv8");
267     break;
268   case ARM::FV_VFPV3_FP16:
269     Features.push_back("+vfp3");
270     Features.push_back("+fp16");
271     Features.push_back("-vfp4");
272     Features.push_back("-fp-armv8");
273     break;
274   case ARM::FV_VFPV3:
275     Features.push_back("+vfp3");
276     Features.push_back("-fp16");
277     Features.push_back("-vfp4");
278     Features.push_back("-fp-armv8");
279     break;
280   case ARM::FV_VFPV2:
281     Features.push_back("+vfp2");
282     Features.push_back("-vfp3");
283     Features.push_back("-fp16");
284     Features.push_back("-vfp4");
285     Features.push_back("-fp-armv8");
286     break;
287   case ARM::FV_NONE:
288     Features.push_back("-vfp2");
289     Features.push_back("-vfp3");
290     Features.push_back("-fp16");
291     Features.push_back("-vfp4");
292     Features.push_back("-fp-armv8");
293     break;
294   }
295 
296   // crypto includes neon, so we handle this similarly to FPU version.
297   switch (FPUNames[FPUKind].NeonSupport) {
298   case ARM::NS_Crypto:
299     Features.push_back("+neon");
300     Features.push_back("+crypto");
301     break;
302   case ARM::NS_Neon:
303     Features.push_back("+neon");
304     Features.push_back("-crypto");
305     break;
306   case ARM::NS_None:
307     Features.push_back("-neon");
308     Features.push_back("-crypto");
309     break;
310   }
311 
312   return true;
313 }
314 
315 StringRef llvm::ARM::getArchName(unsigned ArchKind) {
316   if (ArchKind >= ARM::AK_LAST)
317     return StringRef();
318   return ARCHNames[ArchKind].getName();
319 }
320 
321 StringRef llvm::ARM::getCPUAttr(unsigned ArchKind) {
322   if (ArchKind == ARM::AK_INVALID || ArchKind >= ARM::AK_LAST)
323     return StringRef();
324   return ARCHNames[ArchKind].getCPUAttr();
325 }
326 
327 StringRef llvm::ARM::getSubArch(unsigned ArchKind) {
328   if (ArchKind == ARM::AK_INVALID || ArchKind >= ARM::AK_LAST)
329     return StringRef();
330   return ARCHNames[ArchKind].getSubArch();
331 }
332 
333 unsigned llvm::ARM::getArchAttr(unsigned ArchKind) {
334   if (ArchKind >= ARM::AK_LAST)
335     return ARMBuildAttrs::CPUArch::Pre_v4;
336   return ARCHNames[ArchKind].ArchAttr;
337 }
338 
339 StringRef llvm::ARM::getArchExtName(unsigned ArchExtKind) {
340   for (const auto AE : ARCHExtNames) {
341     if (ArchExtKind == AE.ID)
342       return AE.getName();
343   }
344   return StringRef();
345 }
346 
347 const char *llvm::ARM::getArchExtFeature(StringRef ArchExt) {
348   if (ArchExt.startswith("no")) {
349     StringRef ArchExtBase(ArchExt.substr(2));
350     for (const auto AE : ARCHExtNames) {
351       if (AE.NegFeature && ArchExtBase == AE.getName())
352         return AE.NegFeature;
353     }
354   }
355   for (const auto AE : ARCHExtNames) {
356     if (AE.Feature && ArchExt == AE.getName())
357       return AE.Feature;
358   }
359 
360   return nullptr;
361 }
362 
363 StringRef llvm::ARM::getHWDivName(unsigned HWDivKind) {
364   for (const auto D : HWDivNames) {
365     if (HWDivKind == D.ID)
366       return D.getName();
367   }
368   return StringRef();
369 }
370 
371 StringRef llvm::ARM::getDefaultCPU(StringRef Arch) {
372   unsigned AK = parseArch(Arch);
373   if (AK == ARM::AK_INVALID)
374     return StringRef();
375 
376   // Look for multiple AKs to find the default for pair AK+Name.
377   for (const auto CPU : CPUNames) {
378     if (CPU.ArchID == AK && CPU.Default)
379       return CPU.getName();
380   }
381 
382   // If we can't find a default then target the architecture instead
383   return "generic";
384 }
385 
386 StringRef llvm::AArch64::getFPUName(unsigned FPUKind) {
387   return ARM::getFPUName(FPUKind);
388 }
389 
390 unsigned llvm::AArch64::getFPUVersion(unsigned FPUKind) {
391   return ARM::getFPUVersion(FPUKind);
392 }
393 
394 unsigned llvm::AArch64::getFPUNeonSupportLevel(unsigned FPUKind) {
395   return ARM::getFPUNeonSupportLevel( FPUKind);
396 }
397 
398 unsigned llvm::AArch64::getFPURestriction(unsigned FPUKind) {
399   return ARM::getFPURestriction(FPUKind);
400 }
401 
402 unsigned llvm::AArch64::getDefaultFPU(StringRef CPU, unsigned ArchKind) {
403   if (CPU == "generic")
404     return AArch64ARCHNames[ArchKind].DefaultFPU;
405 
406   return StringSwitch<unsigned>(CPU)
407 #define AARCH64_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT) \
408     .Case(NAME, DEFAULT_FPU)
409 #include "llvm/Support/AArch64TargetParser.def"
410     .Default(ARM::FK_INVALID);
411 }
412 
413 unsigned llvm::AArch64::getDefaultExtensions(StringRef CPU, unsigned ArchKind) {
414   if (CPU == "generic")
415     return AArch64ARCHNames[ArchKind].ArchBaseExtensions;
416 
417   return StringSwitch<unsigned>(CPU)
418 #define AARCH64_CPU_NAME(NAME, ID, DEFAULT_FPU, IS_DEFAULT, DEFAULT_EXT) \
419     .Case(NAME, AArch64ARCHNames[ID].ArchBaseExtensions | DEFAULT_EXT)
420 #include "llvm/Support/AArch64TargetParser.def"
421     .Default(AArch64::AEK_INVALID);
422 }
423 
424 bool llvm::AArch64::getExtensionFeatures(unsigned Extensions,
425                                      std::vector<const char *> &Features) {
426 
427   if (Extensions == AArch64::AEK_INVALID)
428     return false;
429 
430   if (Extensions & AArch64::AEK_FP)
431     Features.push_back("+fp-armv8");
432   if (Extensions & AArch64::AEK_SIMD)
433     Features.push_back("+neon");
434   if (Extensions & AArch64::AEK_CRC)
435     Features.push_back("+crc");
436   if (Extensions & AArch64::AEK_CRYPTO)
437     Features.push_back("+crypto");
438   if (Extensions & AArch64::AEK_FP16)
439     Features.push_back("+fullfp16");
440   if (Extensions & AArch64::AEK_PROFILE)
441     Features.push_back("+spe");
442 
443   return true;
444 }
445 
446 bool llvm::AArch64::getFPUFeatures(unsigned FPUKind,
447                                std::vector<const char *> &Features) {
448   return ARM::getFPUFeatures(FPUKind, Features);
449 }
450 
451 bool llvm::AArch64::getArchFeatures(unsigned ArchKind,
452                                      std::vector<const char *> &Features) {
453   if (ArchKind == ARM::AK_INVALID || ArchKind >= ARM::AK_LAST)
454     return false;
455 
456   if (ArchKind == ARM::AK_ARMV8_1A)
457     Features.push_back("+v8.1a");
458   if (ArchKind == ARM::AK_ARMV8_2A)
459     Features.push_back("+v8.2a");
460 
461   return true;
462 }
463 
464 StringRef llvm::AArch64::getArchName(unsigned ArchKind) {
465   for (const auto &AI : AArch64ARCHNames)
466     if (AI.ID == ArchKind)
467       return AI.getName();
468   return StringRef();
469 }
470 
471 StringRef llvm::AArch64::getCPUAttr(unsigned ArchKind) {
472   for (const auto &AI : AArch64ARCHNames)
473     if (AI.ID == ArchKind)
474       return AI.getCPUAttr();
475   return StringRef();
476 }
477 
478 StringRef llvm::AArch64::getSubArch(unsigned ArchKind) {
479   for (const auto &AI : AArch64ARCHNames)
480     if (AI.ID == ArchKind)
481       return AI.getSubArch();
482   return StringRef();
483 }
484 
485 unsigned llvm::AArch64::getArchAttr(unsigned ArchKind) {
486   for (const auto &AI : AArch64ARCHNames)
487     if (AI.ID == ArchKind)
488       return AI.ArchAttr;
489   return ARMBuildAttrs::CPUArch::v8_A;
490 }
491 
492 StringRef llvm::AArch64::getArchExtName(unsigned AArchExtKind) {
493   for (const auto &AE : AArch64ARCHExtNames)
494     if (AArchExtKind == AE.ID)
495       return AE.getName();
496   return StringRef();
497 }
498 
499 const char *llvm::AArch64::getArchExtFeature(StringRef ArchExt) {
500   if (ArchExt.startswith("no")) {
501     StringRef ArchExtBase(ArchExt.substr(2));
502     for (const auto &AE : AArch64ARCHExtNames) {
503       if (AE.NegFeature && ArchExtBase == AE.getName())
504         return AE.NegFeature;
505     }
506   }
507 
508   for (const auto &AE : AArch64ARCHExtNames)
509     if (AE.Feature && ArchExt == AE.getName())
510       return AE.Feature;
511   return nullptr;
512 }
513 
514 StringRef llvm::AArch64::getDefaultCPU(StringRef Arch) {
515   unsigned AK = parseArch(Arch);
516   if (AK == ARM::AK_INVALID)
517     return StringRef();
518 
519   // Look for multiple AKs to find the default for pair AK+Name.
520   for (const auto &CPU : AArch64CPUNames)
521     if (CPU.ArchID == AK && CPU.Default)
522       return CPU.getName();
523 
524   // If we can't find a default then target the architecture instead
525   return "generic";
526 }
527 
528 unsigned llvm::AArch64::checkArchVersion(StringRef Arch) {
529   if (Arch[0] == 'v' && std::isdigit(Arch[1]))
530     return (Arch[1] - 48);
531   return 0;
532 }
533 
534 // ======================================================= //
535 // Parsers
536 // ======================================================= //
537 
538 static StringRef getHWDivSynonym(StringRef HWDiv) {
539   return StringSwitch<StringRef>(HWDiv)
540       .Case("thumb,arm", "arm,thumb")
541       .Default(HWDiv);
542 }
543 
544 static StringRef getFPUSynonym(StringRef FPU) {
545   return StringSwitch<StringRef>(FPU)
546       .Cases("fpa", "fpe2", "fpe3", "maverick", "invalid") // Unsupported
547       .Case("vfp2", "vfpv2")
548       .Case("vfp3", "vfpv3")
549       .Case("vfp4", "vfpv4")
550       .Case("vfp3-d16", "vfpv3-d16")
551       .Case("vfp4-d16", "vfpv4-d16")
552       .Cases("fp4-sp-d16", "vfpv4-sp-d16", "fpv4-sp-d16")
553       .Cases("fp4-dp-d16", "fpv4-dp-d16", "vfpv4-d16")
554       .Case("fp5-sp-d16", "fpv5-sp-d16")
555       .Cases("fp5-dp-d16", "fpv5-dp-d16", "fpv5-d16")
556       // FIXME: Clang uses it, but it's bogus, since neon defaults to vfpv3.
557       .Case("neon-vfpv3", "neon")
558       .Default(FPU);
559 }
560 
561 static StringRef getArchSynonym(StringRef Arch) {
562   return StringSwitch<StringRef>(Arch)
563       .Case("v5", "v5t")
564       .Case("v5e", "v5te")
565       .Case("v6j", "v6")
566       .Case("v6hl", "v6k")
567       .Cases("v6m", "v6sm", "v6s-m", "v6-m")
568       .Cases("v6z", "v6zk", "v6kz")
569       .Cases("v7", "v7a", "v7hl", "v7l", "v7-a")
570       .Case("v7r", "v7-r")
571       .Case("v7m", "v7-m")
572       .Case("v7em", "v7e-m")
573       .Cases("v8", "v8a", "aarch64", "arm64", "v8-a")
574       .Case("v8.1a", "v8.1-a")
575       .Case("v8.2a", "v8.2-a")
576       .Case("v8m.base", "v8-m.base")
577       .Case("v8m.main", "v8-m.main")
578       .Default(Arch);
579 }
580 
581 // MArch is expected to be of the form (arm|thumb)?(eb)?(v.+)?(eb)?, but
582 // (iwmmxt|xscale)(eb)? is also permitted. If the former, return
583 // "v.+", if the latter, return unmodified string, minus 'eb'.
584 // If invalid, return empty string.
585 StringRef llvm::ARM::getCanonicalArchName(StringRef Arch) {
586   size_t offset = StringRef::npos;
587   StringRef A = Arch;
588   StringRef Error = "";
589 
590   // Begins with "arm" / "thumb", move past it.
591   if (A.startswith("arm64"))
592     offset = 5;
593   else if (A.startswith("arm"))
594     offset = 3;
595   else if (A.startswith("thumb"))
596     offset = 5;
597   else if (A.startswith("aarch64")) {
598     offset = 7;
599     // AArch64 uses "_be", not "eb" suffix.
600     if (A.find("eb") != StringRef::npos)
601       return Error;
602     if (A.substr(offset, 3) == "_be")
603       offset += 3;
604   }
605 
606   // Ex. "armebv7", move past the "eb".
607   if (offset != StringRef::npos && A.substr(offset, 2) == "eb")
608     offset += 2;
609   // Or, if it ends with eb ("armv7eb"), chop it off.
610   else if (A.endswith("eb"))
611     A = A.substr(0, A.size() - 2);
612   // Trim the head
613   if (offset != StringRef::npos)
614     A = A.substr(offset);
615 
616   // Empty string means offset reached the end, which means it's valid.
617   if (A.empty())
618     return Arch;
619 
620   // Only match non-marketing names
621   if (offset != StringRef::npos) {
622     // Must start with 'vN'.
623     if (A[0] != 'v' || !std::isdigit(A[1]))
624       return Error;
625     // Can't have an extra 'eb'.
626     if (A.find("eb") != StringRef::npos)
627       return Error;
628   }
629 
630   // Arch will either be a 'v' name (v7a) or a marketing name (xscale).
631   return A;
632 }
633 
634 unsigned llvm::ARM::parseHWDiv(StringRef HWDiv) {
635   StringRef Syn = getHWDivSynonym(HWDiv);
636   for (const auto D : HWDivNames) {
637     if (Syn == D.getName())
638       return D.ID;
639   }
640   return ARM::AEK_INVALID;
641 }
642 
643 unsigned llvm::ARM::parseFPU(StringRef FPU) {
644   StringRef Syn = getFPUSynonym(FPU);
645   for (const auto F : FPUNames) {
646     if (Syn == F.getName())
647       return F.ID;
648   }
649   return ARM::FK_INVALID;
650 }
651 
652 // Allows partial match, ex. "v7a" matches "armv7a".
653 unsigned llvm::ARM::parseArch(StringRef Arch) {
654   Arch = getCanonicalArchName(Arch);
655   StringRef Syn = getArchSynonym(Arch);
656   for (const auto A : ARCHNames) {
657     if (A.getName().endswith(Syn))
658       return A.ID;
659   }
660   return ARM::AK_INVALID;
661 }
662 
663 unsigned llvm::ARM::parseArchExt(StringRef ArchExt) {
664   for (const auto A : ARCHExtNames) {
665     if (ArchExt == A.getName())
666       return A.ID;
667   }
668   return ARM::AEK_INVALID;
669 }
670 
671 unsigned llvm::ARM::parseCPUArch(StringRef CPU) {
672   for (const auto C : CPUNames) {
673     if (CPU == C.getName())
674       return C.ArchID;
675   }
676   return ARM::AK_INVALID;
677 }
678 
679 // ARM, Thumb, AArch64
680 unsigned llvm::ARM::parseArchISA(StringRef Arch) {
681   return StringSwitch<unsigned>(Arch)
682       .StartsWith("aarch64", ARM::IK_AARCH64)
683       .StartsWith("arm64", ARM::IK_AARCH64)
684       .StartsWith("thumb", ARM::IK_THUMB)
685       .StartsWith("arm", ARM::IK_ARM)
686       .Default(ARM::EK_INVALID);
687 }
688 
689 // Little/Big endian
690 unsigned llvm::ARM::parseArchEndian(StringRef Arch) {
691   if (Arch.startswith("armeb") || Arch.startswith("thumbeb") ||
692       Arch.startswith("aarch64_be"))
693     return ARM::EK_BIG;
694 
695   if (Arch.startswith("arm") || Arch.startswith("thumb")) {
696     if (Arch.endswith("eb"))
697       return ARM::EK_BIG;
698     else
699       return ARM::EK_LITTLE;
700   }
701 
702   if (Arch.startswith("aarch64"))
703     return ARM::EK_LITTLE;
704 
705   return ARM::EK_INVALID;
706 }
707 
708 // Profile A/R/M
709 unsigned llvm::ARM::parseArchProfile(StringRef Arch) {
710   Arch = getCanonicalArchName(Arch);
711   switch (parseArch(Arch)) {
712   case ARM::AK_ARMV6M:
713   case ARM::AK_ARMV7M:
714   case ARM::AK_ARMV7EM:
715   case ARM::AK_ARMV8MMainline:
716   case ARM::AK_ARMV8MBaseline:
717     return ARM::PK_M;
718   case ARM::AK_ARMV7R:
719     return ARM::PK_R;
720   case ARM::AK_ARMV7A:
721   case ARM::AK_ARMV7K:
722   case ARM::AK_ARMV8A:
723   case ARM::AK_ARMV8_1A:
724   case ARM::AK_ARMV8_2A:
725     return ARM::PK_A;
726   }
727   return ARM::PK_INVALID;
728 }
729 
730 // Version number (ex. v7 = 7).
731 unsigned llvm::ARM::parseArchVersion(StringRef Arch) {
732   Arch = getCanonicalArchName(Arch);
733   switch (parseArch(Arch)) {
734   case ARM::AK_ARMV2:
735   case ARM::AK_ARMV2A:
736     return 2;
737   case ARM::AK_ARMV3:
738   case ARM::AK_ARMV3M:
739     return 3;
740   case ARM::AK_ARMV4:
741   case ARM::AK_ARMV4T:
742     return 4;
743   case ARM::AK_ARMV5T:
744   case ARM::AK_ARMV5TE:
745   case ARM::AK_IWMMXT:
746   case ARM::AK_IWMMXT2:
747   case ARM::AK_XSCALE:
748   case ARM::AK_ARMV5TEJ:
749     return 5;
750   case ARM::AK_ARMV6:
751   case ARM::AK_ARMV6K:
752   case ARM::AK_ARMV6T2:
753   case ARM::AK_ARMV6KZ:
754   case ARM::AK_ARMV6M:
755     return 6;
756   case ARM::AK_ARMV7A:
757   case ARM::AK_ARMV7R:
758   case ARM::AK_ARMV7M:
759   case ARM::AK_ARMV7S:
760   case ARM::AK_ARMV7EM:
761   case ARM::AK_ARMV7K:
762     return 7;
763   case ARM::AK_ARMV8A:
764   case ARM::AK_ARMV8_1A:
765   case ARM::AK_ARMV8_2A:
766   case ARM::AK_ARMV8MBaseline:
767   case ARM::AK_ARMV8MMainline:
768     return 8;
769   }
770   return 0;
771 }
772 
773 StringRef llvm::AArch64::getCanonicalArchName(StringRef Arch) {
774   return ARM::getCanonicalArchName(Arch);
775 }
776 
777 unsigned llvm::AArch64::parseFPU(StringRef FPU) {
778   return ARM::parseFPU(FPU);
779 }
780 
781 // Allows partial match, ex. "v8a" matches "armv8a".
782 unsigned llvm::AArch64::parseArch(StringRef Arch) {
783   Arch = getCanonicalArchName(Arch);
784   if (checkArchVersion(Arch) < 8)
785     return ARM::AK_INVALID;
786 
787   StringRef Syn = getArchSynonym(Arch);
788   for (const auto A : AArch64ARCHNames) {
789     if (A.getName().endswith(Syn))
790       return A.ID;
791   }
792   return ARM::AK_INVALID;
793 }
794 
795 unsigned llvm::AArch64::parseArchExt(StringRef ArchExt) {
796   for (const auto A : AArch64ARCHExtNames) {
797     if (ArchExt == A.getName())
798       return A.ID;
799   }
800   return AArch64::AEK_INVALID;
801 }
802 
803 unsigned llvm::AArch64::parseCPUArch(StringRef CPU) {
804   for (const auto C : AArch64CPUNames) {
805     if (CPU == C.getName())
806       return C.ArchID;
807   }
808   return ARM::AK_INVALID;
809 }
810 
811 // ARM, Thumb, AArch64
812 unsigned llvm::AArch64::parseArchISA(StringRef Arch) {
813   return ARM::parseArchISA(Arch);
814 }
815 
816 // Little/Big endian
817 unsigned llvm::AArch64::parseArchEndian(StringRef Arch) {
818   return ARM::parseArchEndian(Arch);
819 }
820 
821 // Profile A/R/M
822 unsigned llvm::AArch64::parseArchProfile(StringRef Arch) {
823   return ARM::parseArchProfile(Arch);
824 }
825 
826 // Version number (ex. v8 = 8).
827 unsigned llvm::AArch64::parseArchVersion(StringRef Arch) {
828   return ARM::parseArchVersion(Arch);
829 }
830