xref: /llvm-project/llvm/lib/Support/ARMAttributeParser.cpp (revision 2946cd701067404b99c39fb29dc9c74bd7193eb3)
1 //===--- ARMAttributeParser.cpp - ARM Attribute Information Printer -------===//
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 "llvm/Support/ARMAttributeParser.h"
10 #include "llvm/ADT/STLExtras.h"
11 #include "llvm/ADT/StringExtras.h"
12 #include "llvm/Support/LEB128.h"
13 #include "llvm/Support/ScopedPrinter.h"
14 
15 using namespace llvm;
16 using namespace llvm::ARMBuildAttrs;
17 
18 
19 static const EnumEntry<unsigned> TagNames[] = {
20   { "Tag_File", ARMBuildAttrs::File },
21   { "Tag_Section", ARMBuildAttrs::Section },
22   { "Tag_Symbol", ARMBuildAttrs::Symbol },
23 };
24 
25 namespace llvm {
26 #define ATTRIBUTE_HANDLER(Attr_)                                                \
27   { ARMBuildAttrs::Attr_, &ARMAttributeParser::Attr_ }
28 
29 const ARMAttributeParser::DisplayHandler
30 ARMAttributeParser::DisplayRoutines[] = {
31   { ARMBuildAttrs::CPU_raw_name, &ARMAttributeParser::StringAttribute, },
32   { ARMBuildAttrs::CPU_name, &ARMAttributeParser::StringAttribute },
33   ATTRIBUTE_HANDLER(CPU_arch),
34   ATTRIBUTE_HANDLER(CPU_arch_profile),
35   ATTRIBUTE_HANDLER(ARM_ISA_use),
36   ATTRIBUTE_HANDLER(THUMB_ISA_use),
37   ATTRIBUTE_HANDLER(FP_arch),
38   ATTRIBUTE_HANDLER(WMMX_arch),
39   ATTRIBUTE_HANDLER(Advanced_SIMD_arch),
40   ATTRIBUTE_HANDLER(PCS_config),
41   ATTRIBUTE_HANDLER(ABI_PCS_R9_use),
42   ATTRIBUTE_HANDLER(ABI_PCS_RW_data),
43   ATTRIBUTE_HANDLER(ABI_PCS_RO_data),
44   ATTRIBUTE_HANDLER(ABI_PCS_GOT_use),
45   ATTRIBUTE_HANDLER(ABI_PCS_wchar_t),
46   ATTRIBUTE_HANDLER(ABI_FP_rounding),
47   ATTRIBUTE_HANDLER(ABI_FP_denormal),
48   ATTRIBUTE_HANDLER(ABI_FP_exceptions),
49   ATTRIBUTE_HANDLER(ABI_FP_user_exceptions),
50   ATTRIBUTE_HANDLER(ABI_FP_number_model),
51   ATTRIBUTE_HANDLER(ABI_align_needed),
52   ATTRIBUTE_HANDLER(ABI_align_preserved),
53   ATTRIBUTE_HANDLER(ABI_enum_size),
54   ATTRIBUTE_HANDLER(ABI_HardFP_use),
55   ATTRIBUTE_HANDLER(ABI_VFP_args),
56   ATTRIBUTE_HANDLER(ABI_WMMX_args),
57   ATTRIBUTE_HANDLER(ABI_optimization_goals),
58   ATTRIBUTE_HANDLER(ABI_FP_optimization_goals),
59   ATTRIBUTE_HANDLER(compatibility),
60   ATTRIBUTE_HANDLER(CPU_unaligned_access),
61   ATTRIBUTE_HANDLER(FP_HP_extension),
62   ATTRIBUTE_HANDLER(ABI_FP_16bit_format),
63   ATTRIBUTE_HANDLER(MPextension_use),
64   ATTRIBUTE_HANDLER(DIV_use),
65   ATTRIBUTE_HANDLER(DSP_extension),
66   ATTRIBUTE_HANDLER(T2EE_use),
67   ATTRIBUTE_HANDLER(Virtualization_use),
68   ATTRIBUTE_HANDLER(nodefaults)
69 };
70 
71 #undef ATTRIBUTE_HANDLER
72 
73 uint64_t ARMAttributeParser::ParseInteger(const uint8_t *Data,
74                                           uint32_t &Offset) {
75   unsigned Length;
76   uint64_t Value = decodeULEB128(Data + Offset, &Length);
77   Offset = Offset + Length;
78   return Value;
79 }
80 
81 StringRef ARMAttributeParser::ParseString(const uint8_t *Data,
82                                           uint32_t &Offset) {
83   const char *String = reinterpret_cast<const char*>(Data + Offset);
84   size_t Length = std::strlen(String);
85   Offset = Offset + Length + 1;
86   return StringRef(String, Length);
87 }
88 
89 void ARMAttributeParser::IntegerAttribute(AttrType Tag, const uint8_t *Data,
90                                           uint32_t &Offset) {
91 
92   uint64_t Value = ParseInteger(Data, Offset);
93   Attributes.insert(std::make_pair(Tag, Value));
94 
95   if (SW)
96     SW->printNumber(ARMBuildAttrs::AttrTypeAsString(Tag), Value);
97 }
98 
99 void ARMAttributeParser::StringAttribute(AttrType Tag, const uint8_t *Data,
100                                          uint32_t &Offset) {
101   StringRef TagName = ARMBuildAttrs::AttrTypeAsString(Tag, /*TagPrefix*/false);
102   StringRef ValueDesc = ParseString(Data, Offset);
103 
104   if (SW) {
105     DictScope AS(*SW, "Attribute");
106     SW->printNumber("Tag", Tag);
107     if (!TagName.empty())
108       SW->printString("TagName", TagName);
109     SW->printString("Value", ValueDesc);
110   }
111 }
112 
113 void ARMAttributeParser::PrintAttribute(unsigned Tag, unsigned Value,
114                                         StringRef ValueDesc) {
115   Attributes.insert(std::make_pair(Tag, Value));
116 
117   if (SW) {
118     StringRef TagName = ARMBuildAttrs::AttrTypeAsString(Tag,
119                                                         /*TagPrefix*/false);
120     DictScope AS(*SW, "Attribute");
121     SW->printNumber("Tag", Tag);
122     SW->printNumber("Value", Value);
123     if (!TagName.empty())
124       SW->printString("TagName", TagName);
125     if (!ValueDesc.empty())
126       SW->printString("Description", ValueDesc);
127   }
128 }
129 
130 void ARMAttributeParser::CPU_arch(AttrType Tag, const uint8_t *Data,
131                                   uint32_t &Offset) {
132   static const char *const Strings[] = {
133     "Pre-v4", "ARM v4", "ARM v4T", "ARM v5T", "ARM v5TE", "ARM v5TEJ", "ARM v6",
134     "ARM v6KZ", "ARM v6T2", "ARM v6K", "ARM v7", "ARM v6-M", "ARM v6S-M",
135     "ARM v7E-M", "ARM v8"
136   };
137 
138   uint64_t Value = ParseInteger(Data, Offset);
139   StringRef ValueDesc =
140     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
141   PrintAttribute(Tag, Value, ValueDesc);
142 }
143 
144 void ARMAttributeParser::CPU_arch_profile(AttrType Tag, const uint8_t *Data,
145                                           uint32_t &Offset) {
146   uint64_t Encoded = ParseInteger(Data, Offset);
147 
148   StringRef Profile;
149   switch (Encoded) {
150   default:  Profile = "Unknown"; break;
151   case 'A': Profile = "Application"; break;
152   case 'R': Profile = "Real-time"; break;
153   case 'M': Profile = "Microcontroller"; break;
154   case 'S': Profile = "Classic"; break;
155   case 0: Profile = "None"; break;
156   }
157 
158   PrintAttribute(Tag, Encoded, Profile);
159 }
160 
161 void ARMAttributeParser::ARM_ISA_use(AttrType Tag, const uint8_t *Data,
162                                      uint32_t &Offset) {
163   static const char *const Strings[] = { "Not Permitted", "Permitted" };
164 
165   uint64_t Value = ParseInteger(Data, Offset);
166   StringRef ValueDesc =
167     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
168   PrintAttribute(Tag, Value, ValueDesc);
169 }
170 
171 void ARMAttributeParser::THUMB_ISA_use(AttrType Tag, const uint8_t *Data,
172                                        uint32_t &Offset) {
173   static const char *const Strings[] = { "Not Permitted", "Thumb-1", "Thumb-2" };
174 
175   uint64_t Value = ParseInteger(Data, Offset);
176   StringRef ValueDesc =
177     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
178   PrintAttribute(Tag, Value, ValueDesc);
179 }
180 
181 void ARMAttributeParser::FP_arch(AttrType Tag, const uint8_t *Data,
182                                  uint32_t &Offset) {
183   static const char *const Strings[] = {
184     "Not Permitted", "VFPv1", "VFPv2", "VFPv3", "VFPv3-D16", "VFPv4",
185     "VFPv4-D16", "ARMv8-a FP", "ARMv8-a FP-D16"
186   };
187 
188   uint64_t Value = ParseInteger(Data, Offset);
189   StringRef ValueDesc =
190     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
191   PrintAttribute(Tag, Value, ValueDesc);
192 }
193 
194 void ARMAttributeParser::WMMX_arch(AttrType Tag, const uint8_t *Data,
195                                    uint32_t &Offset) {
196   static const char *const Strings[] = { "Not Permitted", "WMMXv1", "WMMXv2" };
197 
198   uint64_t Value = ParseInteger(Data, Offset);
199   StringRef ValueDesc =
200     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
201   PrintAttribute(Tag, Value, ValueDesc);
202 }
203 
204 void ARMAttributeParser::Advanced_SIMD_arch(AttrType Tag, const uint8_t *Data,
205                                             uint32_t &Offset) {
206   static const char *const Strings[] = {
207     "Not Permitted", "NEONv1", "NEONv2+FMA", "ARMv8-a NEON", "ARMv8.1-a NEON"
208   };
209 
210   uint64_t Value = ParseInteger(Data, Offset);
211   StringRef ValueDesc =
212     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
213   PrintAttribute(Tag, Value, ValueDesc);
214 }
215 
216 void ARMAttributeParser::PCS_config(AttrType Tag, const uint8_t *Data,
217                                     uint32_t &Offset) {
218   static const char *const Strings[] = {
219     "None", "Bare Platform", "Linux Application", "Linux DSO", "Palm OS 2004",
220     "Reserved (Palm OS)", "Symbian OS 2004", "Reserved (Symbian OS)"
221   };
222 
223   uint64_t Value = ParseInteger(Data, Offset);
224   StringRef ValueDesc =
225     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
226   PrintAttribute(Tag, Value, ValueDesc);
227 }
228 
229 void ARMAttributeParser::ABI_PCS_R9_use(AttrType Tag, const uint8_t *Data,
230                                         uint32_t &Offset) {
231   static const char *const Strings[] = { "v6", "Static Base", "TLS", "Unused" };
232 
233   uint64_t Value = ParseInteger(Data, Offset);
234   StringRef ValueDesc =
235     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
236   PrintAttribute(Tag, Value, ValueDesc);
237 }
238 
239 void ARMAttributeParser::ABI_PCS_RW_data(AttrType Tag, const uint8_t *Data,
240                                          uint32_t &Offset) {
241   static const char *const Strings[] = {
242     "Absolute", "PC-relative", "SB-relative", "Not Permitted"
243   };
244 
245   uint64_t Value = ParseInteger(Data, Offset);
246   StringRef ValueDesc =
247     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
248   PrintAttribute(Tag, Value, ValueDesc);
249 }
250 
251 void ARMAttributeParser::ABI_PCS_RO_data(AttrType Tag, const uint8_t *Data,
252                                          uint32_t &Offset) {
253   static const char *const Strings[] = {
254     "Absolute", "PC-relative", "Not Permitted"
255   };
256 
257   uint64_t Value = ParseInteger(Data, Offset);
258   StringRef ValueDesc =
259     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
260   PrintAttribute(Tag, Value, ValueDesc);
261 }
262 
263 void ARMAttributeParser::ABI_PCS_GOT_use(AttrType Tag, const uint8_t *Data,
264                                          uint32_t &Offset) {
265   static const char *const Strings[] = {
266     "Not Permitted", "Direct", "GOT-Indirect"
267   };
268 
269   uint64_t Value = ParseInteger(Data, Offset);
270   StringRef ValueDesc =
271     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
272   PrintAttribute(Tag, Value, ValueDesc);
273 }
274 
275 void ARMAttributeParser::ABI_PCS_wchar_t(AttrType Tag, const uint8_t *Data,
276                                          uint32_t &Offset) {
277   static const char *const Strings[] = {
278     "Not Permitted", "Unknown", "2-byte", "Unknown", "4-byte"
279   };
280 
281   uint64_t Value = ParseInteger(Data, Offset);
282   StringRef ValueDesc =
283     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
284   PrintAttribute(Tag, Value, ValueDesc);
285 }
286 
287 void ARMAttributeParser::ABI_FP_rounding(AttrType Tag, const uint8_t *Data,
288                                          uint32_t &Offset) {
289   static const char *const Strings[] = { "IEEE-754", "Runtime" };
290 
291   uint64_t Value = ParseInteger(Data, Offset);
292   StringRef ValueDesc =
293     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
294   PrintAttribute(Tag, Value, ValueDesc);
295 }
296 
297 void ARMAttributeParser::ABI_FP_denormal(AttrType Tag, const uint8_t *Data,
298                                          uint32_t &Offset) {
299   static const char *const Strings[] = {
300     "Unsupported", "IEEE-754", "Sign Only"
301   };
302 
303   uint64_t Value = ParseInteger(Data, Offset);
304   StringRef ValueDesc =
305     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
306   PrintAttribute(Tag, Value, ValueDesc);
307 }
308 
309 void ARMAttributeParser::ABI_FP_exceptions(AttrType Tag, const uint8_t *Data,
310                                            uint32_t &Offset) {
311   static const char *const Strings[] = { "Not Permitted", "IEEE-754" };
312 
313   uint64_t Value = ParseInteger(Data, Offset);
314   StringRef ValueDesc =
315     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
316   PrintAttribute(Tag, Value, ValueDesc);
317 }
318 
319 void ARMAttributeParser::ABI_FP_user_exceptions(AttrType Tag,
320                                                 const uint8_t *Data,
321                                                 uint32_t &Offset) {
322   static const char *const Strings[] = { "Not Permitted", "IEEE-754" };
323 
324   uint64_t Value = ParseInteger(Data, Offset);
325   StringRef ValueDesc =
326     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
327   PrintAttribute(Tag, Value, ValueDesc);
328 }
329 
330 void ARMAttributeParser::ABI_FP_number_model(AttrType Tag, const uint8_t *Data,
331                                              uint32_t &Offset) {
332   static const char *const Strings[] = {
333     "Not Permitted", "Finite Only", "RTABI", "IEEE-754"
334   };
335 
336   uint64_t Value = ParseInteger(Data, Offset);
337   StringRef ValueDesc =
338     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
339   PrintAttribute(Tag, Value, ValueDesc);
340 }
341 
342 void ARMAttributeParser::ABI_align_needed(AttrType Tag, const uint8_t *Data,
343                                           uint32_t &Offset) {
344   static const char *const Strings[] = {
345     "Not Permitted", "8-byte alignment", "4-byte alignment", "Reserved"
346   };
347 
348   uint64_t Value = ParseInteger(Data, Offset);
349 
350   std::string Description;
351   if (Value < array_lengthof(Strings))
352     Description = std::string(Strings[Value]);
353   else if (Value <= 12)
354     Description = std::string("8-byte alignment, ") + utostr(1ULL << Value)
355                 + std::string("-byte extended alignment");
356   else
357     Description = "Invalid";
358 
359   PrintAttribute(Tag, Value, Description);
360 }
361 
362 void ARMAttributeParser::ABI_align_preserved(AttrType Tag, const uint8_t *Data,
363                                              uint32_t &Offset) {
364   static const char *const Strings[] = {
365     "Not Required", "8-byte data alignment", "8-byte data and code alignment",
366     "Reserved"
367   };
368 
369   uint64_t Value = ParseInteger(Data, Offset);
370 
371   std::string Description;
372   if (Value < array_lengthof(Strings))
373     Description = std::string(Strings[Value]);
374   else if (Value <= 12)
375     Description = std::string("8-byte stack alignment, ") +
376                   utostr(1ULL << Value) + std::string("-byte data alignment");
377   else
378     Description = "Invalid";
379 
380   PrintAttribute(Tag, Value, Description);
381 }
382 
383 void ARMAttributeParser::ABI_enum_size(AttrType Tag, const uint8_t *Data,
384                                        uint32_t &Offset) {
385   static const char *const Strings[] = {
386     "Not Permitted", "Packed", "Int32", "External Int32"
387   };
388 
389   uint64_t Value = ParseInteger(Data, Offset);
390   StringRef ValueDesc =
391     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
392   PrintAttribute(Tag, Value, ValueDesc);
393 }
394 
395 void ARMAttributeParser::ABI_HardFP_use(AttrType Tag, const uint8_t *Data,
396                                         uint32_t &Offset) {
397   static const char *const Strings[] = {
398     "Tag_FP_arch", "Single-Precision", "Reserved", "Tag_FP_arch (deprecated)"
399   };
400 
401   uint64_t Value = ParseInteger(Data, Offset);
402   StringRef ValueDesc =
403     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
404   PrintAttribute(Tag, Value, ValueDesc);
405 }
406 
407 void ARMAttributeParser::ABI_VFP_args(AttrType Tag, const uint8_t *Data,
408                                       uint32_t &Offset) {
409   static const char *const Strings[] = {
410     "AAPCS", "AAPCS VFP", "Custom", "Not Permitted"
411   };
412 
413   uint64_t Value = ParseInteger(Data, Offset);
414   StringRef ValueDesc =
415     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
416   PrintAttribute(Tag, Value, ValueDesc);
417 }
418 
419 void ARMAttributeParser::ABI_WMMX_args(AttrType Tag, const uint8_t *Data,
420                                        uint32_t &Offset) {
421   static const char *const Strings[] = { "AAPCS", "iWMMX", "Custom" };
422 
423   uint64_t Value = ParseInteger(Data, Offset);
424   StringRef ValueDesc =
425     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
426   PrintAttribute(Tag, Value, ValueDesc);
427 }
428 
429 void ARMAttributeParser::ABI_optimization_goals(AttrType Tag,
430                                                 const uint8_t *Data,
431                                                 uint32_t &Offset) {
432   static const char *const Strings[] = {
433     "None", "Speed", "Aggressive Speed", "Size", "Aggressive Size", "Debugging",
434     "Best Debugging"
435   };
436 
437   uint64_t Value = ParseInteger(Data, Offset);
438   StringRef ValueDesc =
439     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
440   PrintAttribute(Tag, Value, ValueDesc);
441 }
442 
443 void ARMAttributeParser::ABI_FP_optimization_goals(AttrType Tag,
444                                                    const uint8_t *Data,
445                                                    uint32_t &Offset) {
446   static const char *const Strings[] = {
447     "None", "Speed", "Aggressive Speed", "Size", "Aggressive Size", "Accuracy",
448     "Best Accuracy"
449   };
450 
451   uint64_t Value = ParseInteger(Data, Offset);
452   StringRef ValueDesc =
453     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
454   PrintAttribute(Tag, Value, ValueDesc);
455 }
456 
457 void ARMAttributeParser::compatibility(AttrType Tag, const uint8_t *Data,
458                                        uint32_t &Offset) {
459   uint64_t Integer = ParseInteger(Data, Offset);
460   StringRef String = ParseString(Data, Offset);
461 
462   if (SW) {
463     DictScope AS(*SW, "Attribute");
464     SW->printNumber("Tag", Tag);
465     SW->startLine() << "Value: " << Integer << ", " << String << '\n';
466     SW->printString("TagName", AttrTypeAsString(Tag, /*TagPrefix*/false));
467     switch (Integer) {
468     case 0:
469       SW->printString("Description", StringRef("No Specific Requirements"));
470       break;
471     case 1:
472       SW->printString("Description", StringRef("AEABI Conformant"));
473       break;
474     default:
475       SW->printString("Description", StringRef("AEABI Non-Conformant"));
476       break;
477     }
478   }
479 }
480 
481 void ARMAttributeParser::CPU_unaligned_access(AttrType Tag, const uint8_t *Data,
482                                               uint32_t &Offset) {
483   static const char *const Strings[] = { "Not Permitted", "v6-style" };
484 
485   uint64_t Value = ParseInteger(Data, Offset);
486   StringRef ValueDesc =
487     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
488   PrintAttribute(Tag, Value, ValueDesc);
489 }
490 
491 void ARMAttributeParser::FP_HP_extension(AttrType Tag, const uint8_t *Data,
492                                          uint32_t &Offset) {
493   static const char *const Strings[] = { "If Available", "Permitted" };
494 
495   uint64_t Value = ParseInteger(Data, Offset);
496   StringRef ValueDesc =
497     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
498   PrintAttribute(Tag, Value, ValueDesc);
499 }
500 
501 void ARMAttributeParser::ABI_FP_16bit_format(AttrType Tag, const uint8_t *Data,
502                                              uint32_t &Offset) {
503   static const char *const Strings[] = { "Not Permitted", "IEEE-754", "VFPv3" };
504 
505   uint64_t Value = ParseInteger(Data, Offset);
506   StringRef ValueDesc =
507     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
508   PrintAttribute(Tag, Value, ValueDesc);
509 }
510 
511 void ARMAttributeParser::MPextension_use(AttrType Tag, const uint8_t *Data,
512                                          uint32_t &Offset) {
513   static const char *const Strings[] = { "Not Permitted", "Permitted" };
514 
515   uint64_t Value = ParseInteger(Data, Offset);
516   StringRef ValueDesc =
517     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
518   PrintAttribute(Tag, Value, ValueDesc);
519 }
520 
521 void ARMAttributeParser::DIV_use(AttrType Tag, const uint8_t *Data,
522                                  uint32_t &Offset) {
523   static const char *const Strings[] = {
524     "If Available", "Not Permitted", "Permitted"
525   };
526 
527   uint64_t Value = ParseInteger(Data, Offset);
528   StringRef ValueDesc =
529     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
530   PrintAttribute(Tag, Value, ValueDesc);
531 }
532 
533 void ARMAttributeParser::DSP_extension(AttrType Tag, const uint8_t *Data,
534                                        uint32_t &Offset) {
535   static const char *const Strings[] = { "Not Permitted", "Permitted" };
536 
537   uint64_t Value = ParseInteger(Data, Offset);
538   StringRef ValueDesc =
539     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
540   PrintAttribute(Tag, Value, ValueDesc);
541 }
542 
543 void ARMAttributeParser::T2EE_use(AttrType Tag, const uint8_t *Data,
544                                   uint32_t &Offset) {
545   static const char *const Strings[] = { "Not Permitted", "Permitted" };
546 
547   uint64_t Value = ParseInteger(Data, Offset);
548   StringRef ValueDesc =
549     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
550   PrintAttribute(Tag, Value, ValueDesc);
551 }
552 
553 void ARMAttributeParser::Virtualization_use(AttrType Tag, const uint8_t *Data,
554                                             uint32_t &Offset) {
555   static const char *const Strings[] = {
556     "Not Permitted", "TrustZone", "Virtualization Extensions",
557     "TrustZone + Virtualization Extensions"
558   };
559 
560   uint64_t Value = ParseInteger(Data, Offset);
561   StringRef ValueDesc =
562     (Value < array_lengthof(Strings)) ? Strings[Value] : nullptr;
563   PrintAttribute(Tag, Value, ValueDesc);
564 }
565 
566 void ARMAttributeParser::nodefaults(AttrType Tag, const uint8_t *Data,
567                                     uint32_t &Offset) {
568   uint64_t Value = ParseInteger(Data, Offset);
569   PrintAttribute(Tag, Value, "Unspecified Tags UNDEFINED");
570 }
571 
572 void ARMAttributeParser::ParseIndexList(const uint8_t *Data, uint32_t &Offset,
573                                         SmallVectorImpl<uint8_t> &IndexList) {
574   for (;;) {
575     unsigned Length;
576     uint64_t Value = decodeULEB128(Data + Offset, &Length);
577     Offset = Offset + Length;
578     if (Value == 0)
579       break;
580     IndexList.push_back(Value);
581   }
582 }
583 
584 void ARMAttributeParser::ParseAttributeList(const uint8_t *Data,
585                                             uint32_t &Offset, uint32_t Length) {
586   while (Offset < Length) {
587     unsigned Length;
588     uint64_t Tag = decodeULEB128(Data + Offset, &Length);
589     Offset += Length;
590 
591     bool Handled = false;
592     for (unsigned AHI = 0, AHE = array_lengthof(DisplayRoutines);
593          AHI != AHE && !Handled; ++AHI) {
594       if (uint64_t(DisplayRoutines[AHI].Attribute) == Tag) {
595         (this->*DisplayRoutines[AHI].Routine)(ARMBuildAttrs::AttrType(Tag),
596                                               Data, Offset);
597         Handled = true;
598         break;
599       }
600     }
601     if (!Handled) {
602       if (Tag < 32) {
603         errs() << "unhandled AEABI Tag " << Tag
604                << " (" << ARMBuildAttrs::AttrTypeAsString(Tag) << ")\n";
605         continue;
606       }
607 
608       if (Tag % 2 == 0)
609         IntegerAttribute(ARMBuildAttrs::AttrType(Tag), Data, Offset);
610       else
611         StringAttribute(ARMBuildAttrs::AttrType(Tag), Data, Offset);
612     }
613   }
614 }
615 
616 void ARMAttributeParser::ParseSubsection(const uint8_t *Data, uint32_t Length) {
617   uint32_t Offset = sizeof(uint32_t); /* SectionLength */
618 
619   const char *VendorName = reinterpret_cast<const char*>(Data + Offset);
620   size_t VendorNameLength = std::strlen(VendorName);
621   Offset = Offset + VendorNameLength + 1;
622 
623   if (SW) {
624     SW->printNumber("SectionLength", Length);
625     SW->printString("Vendor", StringRef(VendorName, VendorNameLength));
626   }
627 
628   if (StringRef(VendorName, VendorNameLength).lower() != "aeabi") {
629     return;
630   }
631 
632   while (Offset < Length) {
633     /// Tag_File | Tag_Section | Tag_Symbol   uleb128:byte-size
634     uint8_t Tag = Data[Offset];
635     Offset = Offset + sizeof(Tag);
636 
637     uint32_t Size =
638       *reinterpret_cast<const support::ulittle32_t*>(Data + Offset);
639     Offset = Offset + sizeof(Size);
640 
641     if (SW) {
642       SW->printEnum("Tag", Tag, makeArrayRef(TagNames));
643       SW->printNumber("Size", Size);
644     }
645 
646     if (Size > Length) {
647       errs() << "subsection length greater than section length\n";
648       return;
649     }
650 
651     StringRef ScopeName, IndexName;
652     SmallVector<uint8_t, 8> Indicies;
653     switch (Tag) {
654     case ARMBuildAttrs::File:
655       ScopeName = "FileAttributes";
656       break;
657     case ARMBuildAttrs::Section:
658       ScopeName = "SectionAttributes";
659       IndexName = "Sections";
660       ParseIndexList(Data, Offset, Indicies);
661       break;
662     case ARMBuildAttrs::Symbol:
663       ScopeName = "SymbolAttributes";
664       IndexName = "Symbols";
665       ParseIndexList(Data, Offset, Indicies);
666       break;
667     default:
668       errs() << "unrecognised tag: 0x" << Twine::utohexstr(Tag) << '\n';
669       return;
670     }
671 
672     if (SW) {
673       DictScope ASS(*SW, ScopeName);
674       if (!Indicies.empty())
675         SW->printList(IndexName, Indicies);
676       ParseAttributeList(Data, Offset, Length);
677     } else {
678       ParseAttributeList(Data, Offset, Length);
679     }
680   }
681 }
682 
683 void ARMAttributeParser::Parse(ArrayRef<uint8_t> Section, bool isLittle) {
684   size_t Offset = 1;
685   unsigned SectionNumber = 0;
686 
687   while (Offset < Section.size()) {
688     uint32_t SectionLength = isLittle ?
689       support::endian::read32le(Section.data() + Offset) :
690       support::endian::read32be(Section.data() + Offset);
691 
692     if (SW) {
693       SW->startLine() << "Section " << ++SectionNumber << " {\n";
694       SW->indent();
695     }
696 
697     ParseSubsection(Section.data() + Offset, SectionLength);
698     Offset = Offset + SectionLength;
699 
700     if (SW) {
701       SW->unindent();
702       SW->startLine() << "}\n";
703     }
704   }
705 }
706 }
707