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   if (ArchKind >= ARM::AK_LAST)
466     return StringRef();
467   return AArch64ARCHNames[ArchKind].getName();
468 }
469 
470 StringRef llvm::AArch64::getCPUAttr(unsigned ArchKind) {
471   if (ArchKind == ARM::AK_INVALID || ArchKind >= ARM::AK_LAST)
472     return StringRef();
473   return AArch64ARCHNames[ArchKind].getCPUAttr();
474 }
475 
476 StringRef llvm::AArch64::getSubArch(unsigned ArchKind) {
477   if (ArchKind == ARM::AK_INVALID || ArchKind >= ARM::AK_LAST)
478     return StringRef();
479   return AArch64ARCHNames[ArchKind].getSubArch();
480 }
481 
482 unsigned llvm::AArch64::getArchAttr(unsigned ArchKind) {
483   if (ArchKind >= ARM::AK_LAST)
484     return ARMBuildAttrs::CPUArch::v8_A;
485   return AArch64ARCHNames[ArchKind].ArchAttr;
486 }
487 
488 StringRef llvm::AArch64::getArchExtName(unsigned AArchExtKind) {
489   for (const auto AE : AArch64ARCHExtNames) {
490     if (AArchExtKind == AE.ID)
491       return AE.getName();
492   }
493   return StringRef();
494 }
495 
496 const char *llvm::AArch64::getArchExtFeature(StringRef ArchExt) {
497   if (ArchExt.startswith("no")) {
498     StringRef ArchExtBase(ArchExt.substr(2));
499     for (const auto AE : AArch64ARCHExtNames) {
500       if (AE.NegFeature && ArchExtBase == AE.getName())
501         return AE.NegFeature;
502     }
503   }
504   for (const auto AE : AArch64ARCHExtNames) {
505     if (AE.Feature && ArchExt == AE.getName())
506       return AE.Feature;
507   }
508 
509   return nullptr;
510 }
511 
512 StringRef llvm::AArch64::getDefaultCPU(StringRef Arch) {
513   unsigned AK = parseArch(Arch);
514   if (AK == ARM::AK_INVALID)
515     return StringRef();
516 
517   // Look for multiple AKs to find the default for pair AK+Name.
518   for (const auto CPU : AArch64CPUNames) {
519     if (CPU.ArchID == AK && CPU.Default)
520       return CPU.getName();
521   }
522 
523   // If we can't find a default then target the architecture instead
524   return "generic";
525 }
526 
527 unsigned llvm::AArch64::checkArchVersion(StringRef Arch) {
528   if (Arch[0] == 'v' && std::isdigit(Arch[1]))
529     return (Arch[1] - 48);
530   return 0;
531 }
532 
533 // ======================================================= //
534 // Parsers
535 // ======================================================= //
536 
537 static StringRef getHWDivSynonym(StringRef HWDiv) {
538   return StringSwitch<StringRef>(HWDiv)
539       .Case("thumb,arm", "arm,thumb")
540       .Default(HWDiv);
541 }
542 
543 static StringRef getFPUSynonym(StringRef FPU) {
544   return StringSwitch<StringRef>(FPU)
545       .Cases("fpa", "fpe2", "fpe3", "maverick", "invalid") // Unsupported
546       .Case("vfp2", "vfpv2")
547       .Case("vfp3", "vfpv3")
548       .Case("vfp4", "vfpv4")
549       .Case("vfp3-d16", "vfpv3-d16")
550       .Case("vfp4-d16", "vfpv4-d16")
551       .Cases("fp4-sp-d16", "vfpv4-sp-d16", "fpv4-sp-d16")
552       .Cases("fp4-dp-d16", "fpv4-dp-d16", "vfpv4-d16")
553       .Case("fp5-sp-d16", "fpv5-sp-d16")
554       .Cases("fp5-dp-d16", "fpv5-dp-d16", "fpv5-d16")
555       // FIXME: Clang uses it, but it's bogus, since neon defaults to vfpv3.
556       .Case("neon-vfpv3", "neon")
557       .Default(FPU);
558 }
559 
560 static StringRef getArchSynonym(StringRef Arch) {
561   return StringSwitch<StringRef>(Arch)
562       .Case("v5", "v5t")
563       .Case("v5e", "v5te")
564       .Case("v6j", "v6")
565       .Case("v6hl", "v6k")
566       .Cases("v6m", "v6sm", "v6s-m", "v6-m")
567       .Cases("v6z", "v6zk", "v6kz")
568       .Cases("v7", "v7a", "v7hl", "v7l", "v7-a")
569       .Case("v7r", "v7-r")
570       .Case("v7m", "v7-m")
571       .Case("v7em", "v7e-m")
572       .Cases("v8", "v8a", "aarch64", "arm64", "v8-a")
573       .Case("v8.1a", "v8.1-a")
574       .Case("v8.2a", "v8.2-a")
575       .Case("v8m.base", "v8-m.base")
576       .Case("v8m.main", "v8-m.main")
577       .Default(Arch);
578 }
579 
580 // MArch is expected to be of the form (arm|thumb)?(eb)?(v.+)?(eb)?, but
581 // (iwmmxt|xscale)(eb)? is also permitted. If the former, return
582 // "v.+", if the latter, return unmodified string, minus 'eb'.
583 // If invalid, return empty string.
584 StringRef llvm::ARM::getCanonicalArchName(StringRef Arch) {
585   size_t offset = StringRef::npos;
586   StringRef A = Arch;
587   StringRef Error = "";
588 
589   // Begins with "arm" / "thumb", move past it.
590   if (A.startswith("arm64"))
591     offset = 5;
592   else if (A.startswith("arm"))
593     offset = 3;
594   else if (A.startswith("thumb"))
595     offset = 5;
596   else if (A.startswith("aarch64")) {
597     offset = 7;
598     // AArch64 uses "_be", not "eb" suffix.
599     if (A.find("eb") != StringRef::npos)
600       return Error;
601     if (A.substr(offset, 3) == "_be")
602       offset += 3;
603   }
604 
605   // Ex. "armebv7", move past the "eb".
606   if (offset != StringRef::npos && A.substr(offset, 2) == "eb")
607     offset += 2;
608   // Or, if it ends with eb ("armv7eb"), chop it off.
609   else if (A.endswith("eb"))
610     A = A.substr(0, A.size() - 2);
611   // Trim the head
612   if (offset != StringRef::npos)
613     A = A.substr(offset);
614 
615   // Empty string means offset reached the end, which means it's valid.
616   if (A.empty())
617     return Arch;
618 
619   // Only match non-marketing names
620   if (offset != StringRef::npos) {
621     // Must start with 'vN'.
622     if (A[0] != 'v' || !std::isdigit(A[1]))
623       return Error;
624     // Can't have an extra 'eb'.
625     if (A.find("eb") != StringRef::npos)
626       return Error;
627   }
628 
629   // Arch will either be a 'v' name (v7a) or a marketing name (xscale).
630   return A;
631 }
632 
633 unsigned llvm::ARM::parseHWDiv(StringRef HWDiv) {
634   StringRef Syn = getHWDivSynonym(HWDiv);
635   for (const auto D : HWDivNames) {
636     if (Syn == D.getName())
637       return D.ID;
638   }
639   return ARM::AEK_INVALID;
640 }
641 
642 unsigned llvm::ARM::parseFPU(StringRef FPU) {
643   StringRef Syn = getFPUSynonym(FPU);
644   for (const auto F : FPUNames) {
645     if (Syn == F.getName())
646       return F.ID;
647   }
648   return ARM::FK_INVALID;
649 }
650 
651 // Allows partial match, ex. "v7a" matches "armv7a".
652 unsigned llvm::ARM::parseArch(StringRef Arch) {
653   Arch = getCanonicalArchName(Arch);
654   StringRef Syn = getArchSynonym(Arch);
655   for (const auto A : ARCHNames) {
656     if (A.getName().endswith(Syn))
657       return A.ID;
658   }
659   return ARM::AK_INVALID;
660 }
661 
662 unsigned llvm::ARM::parseArchExt(StringRef ArchExt) {
663   for (const auto A : ARCHExtNames) {
664     if (ArchExt == A.getName())
665       return A.ID;
666   }
667   return ARM::AEK_INVALID;
668 }
669 
670 unsigned llvm::ARM::parseCPUArch(StringRef CPU) {
671   for (const auto C : CPUNames) {
672     if (CPU == C.getName())
673       return C.ArchID;
674   }
675   return ARM::AK_INVALID;
676 }
677 
678 // ARM, Thumb, AArch64
679 unsigned llvm::ARM::parseArchISA(StringRef Arch) {
680   return StringSwitch<unsigned>(Arch)
681       .StartsWith("aarch64", ARM::IK_AARCH64)
682       .StartsWith("arm64", ARM::IK_AARCH64)
683       .StartsWith("thumb", ARM::IK_THUMB)
684       .StartsWith("arm", ARM::IK_ARM)
685       .Default(ARM::EK_INVALID);
686 }
687 
688 // Little/Big endian
689 unsigned llvm::ARM::parseArchEndian(StringRef Arch) {
690   if (Arch.startswith("armeb") || Arch.startswith("thumbeb") ||
691       Arch.startswith("aarch64_be"))
692     return ARM::EK_BIG;
693 
694   if (Arch.startswith("arm") || Arch.startswith("thumb")) {
695     if (Arch.endswith("eb"))
696       return ARM::EK_BIG;
697     else
698       return ARM::EK_LITTLE;
699   }
700 
701   if (Arch.startswith("aarch64"))
702     return ARM::EK_LITTLE;
703 
704   return ARM::EK_INVALID;
705 }
706 
707 // Profile A/R/M
708 unsigned llvm::ARM::parseArchProfile(StringRef Arch) {
709   Arch = getCanonicalArchName(Arch);
710   switch (parseArch(Arch)) {
711   case ARM::AK_ARMV6M:
712   case ARM::AK_ARMV7M:
713   case ARM::AK_ARMV7EM:
714   case ARM::AK_ARMV8MMainline:
715   case ARM::AK_ARMV8MBaseline:
716     return ARM::PK_M;
717   case ARM::AK_ARMV7R:
718     return ARM::PK_R;
719   case ARM::AK_ARMV7A:
720   case ARM::AK_ARMV7K:
721   case ARM::AK_ARMV8A:
722   case ARM::AK_ARMV8_1A:
723   case ARM::AK_ARMV8_2A:
724     return ARM::PK_A;
725   }
726   return ARM::PK_INVALID;
727 }
728 
729 // Version number (ex. v7 = 7).
730 unsigned llvm::ARM::parseArchVersion(StringRef Arch) {
731   Arch = getCanonicalArchName(Arch);
732   switch (parseArch(Arch)) {
733   case ARM::AK_ARMV2:
734   case ARM::AK_ARMV2A:
735     return 2;
736   case ARM::AK_ARMV3:
737   case ARM::AK_ARMV3M:
738     return 3;
739   case ARM::AK_ARMV4:
740   case ARM::AK_ARMV4T:
741     return 4;
742   case ARM::AK_ARMV5T:
743   case ARM::AK_ARMV5TE:
744   case ARM::AK_IWMMXT:
745   case ARM::AK_IWMMXT2:
746   case ARM::AK_XSCALE:
747   case ARM::AK_ARMV5TEJ:
748     return 5;
749   case ARM::AK_ARMV6:
750   case ARM::AK_ARMV6K:
751   case ARM::AK_ARMV6T2:
752   case ARM::AK_ARMV6KZ:
753   case ARM::AK_ARMV6M:
754     return 6;
755   case ARM::AK_ARMV7A:
756   case ARM::AK_ARMV7R:
757   case ARM::AK_ARMV7M:
758   case ARM::AK_ARMV7S:
759   case ARM::AK_ARMV7EM:
760   case ARM::AK_ARMV7K:
761     return 7;
762   case ARM::AK_ARMV8A:
763   case ARM::AK_ARMV8_1A:
764   case ARM::AK_ARMV8_2A:
765   case ARM::AK_ARMV8MBaseline:
766   case ARM::AK_ARMV8MMainline:
767     return 8;
768   }
769   return 0;
770 }
771 
772 StringRef llvm::AArch64::getCanonicalArchName(StringRef Arch) {
773   return ARM::getCanonicalArchName(Arch);
774 }
775 
776 unsigned llvm::AArch64::parseFPU(StringRef FPU) {
777   return ARM::parseFPU(FPU);
778 }
779 
780 // Allows partial match, ex. "v8a" matches "armv8a".
781 unsigned llvm::AArch64::parseArch(StringRef Arch) {
782   Arch = getCanonicalArchName(Arch);
783   if (checkArchVersion(Arch) < 8)
784     return ARM::AK_INVALID;
785 
786   StringRef Syn = getArchSynonym(Arch);
787   for (const auto A : AArch64ARCHNames) {
788     if (A.getName().endswith(Syn))
789       return A.ID;
790   }
791   return ARM::AK_INVALID;
792 }
793 
794 unsigned llvm::AArch64::parseArchExt(StringRef ArchExt) {
795   for (const auto A : AArch64ARCHExtNames) {
796     if (ArchExt == A.getName())
797       return A.ID;
798   }
799   return AArch64::AEK_INVALID;
800 }
801 
802 unsigned llvm::AArch64::parseCPUArch(StringRef CPU) {
803   for (const auto C : AArch64CPUNames) {
804     if (CPU == C.getName())
805       return C.ArchID;
806   }
807   return ARM::AK_INVALID;
808 }
809 
810 // ARM, Thumb, AArch64
811 unsigned llvm::AArch64::parseArchISA(StringRef Arch) {
812   return ARM::parseArchISA(Arch);
813 }
814 
815 // Little/Big endian
816 unsigned llvm::AArch64::parseArchEndian(StringRef Arch) {
817   return ARM::parseArchEndian(Arch);
818 }
819 
820 // Profile A/R/M
821 unsigned llvm::AArch64::parseArchProfile(StringRef Arch) {
822   return ARM::parseArchProfile(Arch);
823 }
824 
825 // Version number (ex. v8 = 8).
826 unsigned llvm::AArch64::parseArchVersion(StringRef Arch) {
827   return ARM::parseArchVersion(Arch);
828 }
829