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[lld][WebAssembly] Perform data relocations during start function
[llvm-project.git] / lldb / source / Symbol / CompactUnwindInfo.cpp
blob830fe5546c1cdcf0b8b6e89ed38c2de20d40e836
1 //===-- CompactUnwindInfo.cpp ---------------------------------------------===//
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 "lldb/Symbol/CompactUnwindInfo.h"
10 #include "lldb/Core/Module.h"
11 #include "lldb/Core/Section.h"
12 #include "lldb/Symbol/ObjectFile.h"
13 #include "lldb/Symbol/UnwindPlan.h"
14 #include "lldb/Target/Process.h"
15 #include "lldb/Target/Target.h"
16 #include "lldb/Utility/ArchSpec.h"
17 #include "lldb/Utility/DataBufferHeap.h"
18 #include "lldb/Utility/Log.h"
19 #include "lldb/Utility/StreamString.h"
20
21 #include "llvm/Support/MathExtras.h"
22
23 #include <algorithm>
24 #include <memory>
25
26 using namespace lldb;
27 using namespace lldb_private;
28
29 namespace lldb_private {
30
31 // Constants from <mach-o/compact_unwind_encoding.h>
32
33 FLAGS_ANONYMOUS_ENUM(){
34 UNWIND_IS_NOT_FUNCTION_START = 0x80000000, UNWIND_HAS_LSDA = 0x40000000,
35 UNWIND_PERSONALITY_MASK = 0x30000000,
36 };
37
38 FLAGS_ANONYMOUS_ENUM(){
39 UNWIND_X86_MODE_MASK = 0x0F000000,
40 UNWIND_X86_MODE_EBP_FRAME = 0x01000000,
41 UNWIND_X86_MODE_STACK_IMMD = 0x02000000,
42 UNWIND_X86_MODE_STACK_IND = 0x03000000,
43 UNWIND_X86_MODE_DWARF = 0x04000000,
44
45 UNWIND_X86_EBP_FRAME_REGISTERS = 0x00007FFF,
46 UNWIND_X86_EBP_FRAME_OFFSET = 0x00FF0000,
47
48 UNWIND_X86_FRAMELESS_STACK_SIZE = 0x00FF0000,
49 UNWIND_X86_FRAMELESS_STACK_ADJUST = 0x0000E000,
50 UNWIND_X86_FRAMELESS_STACK_REG_COUNT = 0x00001C00,
51 UNWIND_X86_FRAMELESS_STACK_REG_PERMUTATION = 0x000003FF,
52
53 UNWIND_X86_DWARF_SECTION_OFFSET = 0x00FFFFFF,
54 };
55
56 enum {
57 UNWIND_X86_REG_NONE = 0,
58 UNWIND_X86_REG_EBX = 1,
59 UNWIND_X86_REG_ECX = 2,
60 UNWIND_X86_REG_EDX = 3,
61 UNWIND_X86_REG_EDI = 4,
62 UNWIND_X86_REG_ESI = 5,
63 UNWIND_X86_REG_EBP = 6,
64 };
65
66 FLAGS_ANONYMOUS_ENUM(){
67 UNWIND_X86_64_MODE_MASK = 0x0F000000,
68 UNWIND_X86_64_MODE_RBP_FRAME = 0x01000000,
69 UNWIND_X86_64_MODE_STACK_IMMD = 0x02000000,
70 UNWIND_X86_64_MODE_STACK_IND = 0x03000000,
71 UNWIND_X86_64_MODE_DWARF = 0x04000000,
72
73 UNWIND_X86_64_RBP_FRAME_REGISTERS = 0x00007FFF,
74 UNWIND_X86_64_RBP_FRAME_OFFSET = 0x00FF0000,
75
76 UNWIND_X86_64_FRAMELESS_STACK_SIZE = 0x00FF0000,
77 UNWIND_X86_64_FRAMELESS_STACK_ADJUST = 0x0000E000,
78 UNWIND_X86_64_FRAMELESS_STACK_REG_COUNT = 0x00001C00,
79 UNWIND_X86_64_FRAMELESS_STACK_REG_PERMUTATION = 0x000003FF,
80
81 UNWIND_X86_64_DWARF_SECTION_OFFSET = 0x00FFFFFF,
82 };
83
84 enum {
85 UNWIND_X86_64_REG_NONE = 0,
86 UNWIND_X86_64_REG_RBX = 1,
87 UNWIND_X86_64_REG_R12 = 2,
88 UNWIND_X86_64_REG_R13 = 3,
89 UNWIND_X86_64_REG_R14 = 4,
90 UNWIND_X86_64_REG_R15 = 5,
91 UNWIND_X86_64_REG_RBP = 6,
92 };
93
94 FLAGS_ANONYMOUS_ENUM(){
95 UNWIND_ARM64_MODE_MASK = 0x0F000000,
96 UNWIND_ARM64_MODE_FRAMELESS = 0x02000000,
97 UNWIND_ARM64_MODE_DWARF = 0x03000000,
98 UNWIND_ARM64_MODE_FRAME = 0x04000000,
99
100 UNWIND_ARM64_FRAME_X19_X20_PAIR = 0x00000001,
101 UNWIND_ARM64_FRAME_X21_X22_PAIR = 0x00000002,
102 UNWIND_ARM64_FRAME_X23_X24_PAIR = 0x00000004,
103 UNWIND_ARM64_FRAME_X25_X26_PAIR = 0x00000008,
104 UNWIND_ARM64_FRAME_X27_X28_PAIR = 0x00000010,
105 UNWIND_ARM64_FRAME_D8_D9_PAIR = 0x00000100,
106 UNWIND_ARM64_FRAME_D10_D11_PAIR = 0x00000200,
107 UNWIND_ARM64_FRAME_D12_D13_PAIR = 0x00000400,
108 UNWIND_ARM64_FRAME_D14_D15_PAIR = 0x00000800,
109
110 UNWIND_ARM64_FRAMELESS_STACK_SIZE_MASK = 0x00FFF000,
111 UNWIND_ARM64_DWARF_SECTION_OFFSET = 0x00FFFFFF,
112 };
113
114 FLAGS_ANONYMOUS_ENUM(){
115 UNWIND_ARM_MODE_MASK = 0x0F000000,
116 UNWIND_ARM_MODE_FRAME = 0x01000000,
117 UNWIND_ARM_MODE_FRAME_D = 0x02000000,
118 UNWIND_ARM_MODE_DWARF = 0x04000000,
119
120 UNWIND_ARM_FRAME_STACK_ADJUST_MASK = 0x00C00000,
121
122 UNWIND_ARM_FRAME_FIRST_PUSH_R4 = 0x00000001,
123 UNWIND_ARM_FRAME_FIRST_PUSH_R5 = 0x00000002,
124 UNWIND_ARM_FRAME_FIRST_PUSH_R6 = 0x00000004,
125
126 UNWIND_ARM_FRAME_SECOND_PUSH_R8 = 0x00000008,
127 UNWIND_ARM_FRAME_SECOND_PUSH_R9 = 0x00000010,
128 UNWIND_ARM_FRAME_SECOND_PUSH_R10 = 0x00000020,
129 UNWIND_ARM_FRAME_SECOND_PUSH_R11 = 0x00000040,
130 UNWIND_ARM_FRAME_SECOND_PUSH_R12 = 0x00000080,
131
132 UNWIND_ARM_FRAME_D_REG_COUNT_MASK = 0x00000700,
133
134 UNWIND_ARM_DWARF_SECTION_OFFSET = 0x00FFFFFF,
135 };
136 }
137
138 #ifndef UNWIND_SECOND_LEVEL_REGULAR
139 #define UNWIND_SECOND_LEVEL_REGULAR 2
140 #endif
141
142 #ifndef UNWIND_SECOND_LEVEL_COMPRESSED
143 #define UNWIND_SECOND_LEVEL_COMPRESSED 3
144 #endif
145
146 #ifndef UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET
147 #define UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(entry) (entry & 0x00FFFFFF)
148 #endif
149
150 #ifndef UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX
151 #define UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX(entry) \
152 ((entry >> 24) & 0xFF)
153 #endif
154
155 #define EXTRACT_BITS(value, mask) \
156 ((value >> \
157 llvm::countTrailingZeros(static_cast<uint32_t>(mask), llvm::ZB_Width)) & \
158 (((1 << llvm::countPopulation(static_cast<uint32_t>(mask)))) - 1))
159
160 // constructor
161
162 CompactUnwindInfo::CompactUnwindInfo(ObjectFile &objfile, SectionSP &section_sp)
163 : m_objfile(objfile), m_section_sp(section_sp),
164 m_section_contents_if_encrypted(), m_mutex(), m_indexes(),
165 m_indexes_computed(eLazyBoolCalculate), m_unwindinfo_data(),
166 m_unwindinfo_data_computed(false), m_unwind_header() {}
167
168 // destructor
169
170 CompactUnwindInfo::~CompactUnwindInfo() = default;
171
172 bool CompactUnwindInfo::GetUnwindPlan(Target &target, Address addr,
173 UnwindPlan &unwind_plan) {
174 if (!IsValid(target.GetProcessSP())) {
175 return false;
176 }
177 FunctionInfo function_info;
178 if (GetCompactUnwindInfoForFunction(target, addr, function_info)) {
179 // shortcut return for functions that have no compact unwind
180 if (function_info.encoding == 0)
181 return false;
182
183 if (ArchSpec arch = m_objfile.GetArchitecture()) {
184
185 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND));
186 if (log && log->GetVerbose()) {
187 StreamString strm;
188 addr.Dump(
189 &strm, nullptr,
190 Address::DumpStyle::DumpStyleResolvedDescriptionNoFunctionArguments,
191 Address::DumpStyle::DumpStyleFileAddress,
192 arch.GetAddressByteSize());
193 LLDB_LOGF(log, "Got compact unwind encoding 0x%x for function %s",
194 function_info.encoding, strm.GetData());
195 }
196
197 if (function_info.valid_range_offset_start != 0 &&
198 function_info.valid_range_offset_end != 0) {
199 SectionList *sl = m_objfile.GetSectionList();
200 if (sl) {
201 addr_t func_range_start_file_addr =
202 function_info.valid_range_offset_start +
203 m_objfile.GetBaseAddress().GetFileAddress();
204 AddressRange func_range(func_range_start_file_addr,
205 function_info.valid_range_offset_end -
206 function_info.valid_range_offset_start,
207 sl);
208 unwind_plan.SetPlanValidAddressRange(func_range);
209 }
210 }
211
212 if (arch.GetTriple().getArch() == llvm::Triple::x86_64) {
213 return CreateUnwindPlan_x86_64(target, function_info, unwind_plan,
214 addr);
215 }
216 if (arch.GetTriple().getArch() == llvm::Triple::aarch64 ||
217 arch.GetTriple().getArch() == llvm::Triple::aarch64_32) {
218 return CreateUnwindPlan_arm64(target, function_info, unwind_plan, addr);
219 }
220 if (arch.GetTriple().getArch() == llvm::Triple::x86) {
221 return CreateUnwindPlan_i386(target, function_info, unwind_plan, addr);
222 }
223 if (arch.GetTriple().getArch() == llvm::Triple::arm ||
224 arch.GetTriple().getArch() == llvm::Triple::thumb) {
225 return CreateUnwindPlan_armv7(target, function_info, unwind_plan, addr);
226 }
227 }
228 }
229 return false;
230 }
231
232 bool CompactUnwindInfo::IsValid(const ProcessSP &process_sp) {
233 if (m_section_sp.get() == nullptr)
234 return false;
235
236 if (m_indexes_computed == eLazyBoolYes && m_unwindinfo_data_computed)
237 return true;
238
239 ScanIndex(process_sp);
240
241 return m_indexes_computed == eLazyBoolYes && m_unwindinfo_data_computed;
242 }
243
244 void CompactUnwindInfo::ScanIndex(const ProcessSP &process_sp) {
245 std::lock_guard<std::mutex> guard(m_mutex);
246 if (m_indexes_computed == eLazyBoolYes && m_unwindinfo_data_computed)
247 return;
248
249 // We can't read the index for some reason.
250 if (m_indexes_computed == eLazyBoolNo) {
251 return;
252 }
253
254 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND));
255 if (log)
256 m_objfile.GetModule()->LogMessage(
257 log, "Reading compact unwind first-level indexes");
258
259 if (!m_unwindinfo_data_computed) {
260 if (m_section_sp->IsEncrypted()) {
261 // Can't get section contents of a protected/encrypted section until we
262 // have a live process and can read them out of memory.
263 if (process_sp.get() == nullptr)
264 return;
265 m_section_contents_if_encrypted =
266 std::make_shared<DataBufferHeap>(m_section_sp->GetByteSize(), 0);
267 Status error;
268 if (process_sp->ReadMemory(
269 m_section_sp->GetLoadBaseAddress(&process_sp->GetTarget()),
270 m_section_contents_if_encrypted->GetBytes(),
271 m_section_sp->GetByteSize(),
272 error) == m_section_sp->GetByteSize() &&
273 error.Success()) {
274 m_unwindinfo_data.SetAddressByteSize(
275 process_sp->GetTarget().GetArchitecture().GetAddressByteSize());
276 m_unwindinfo_data.SetByteOrder(
277 process_sp->GetTarget().GetArchitecture().GetByteOrder());
278 m_unwindinfo_data.SetData(m_section_contents_if_encrypted, 0);
279 }
280 } else {
281 m_objfile.ReadSectionData(m_section_sp.get(), m_unwindinfo_data);
282 }
283 if (m_unwindinfo_data.GetByteSize() != m_section_sp->GetByteSize())
284 return;
285 m_unwindinfo_data_computed = true;
286 }
287
288 if (m_unwindinfo_data.GetByteSize() > 0) {
289 offset_t offset = 0;
290
291 // struct unwind_info_section_header
292 // {
293 // uint32_t version; // UNWIND_SECTION_VERSION
294 // uint32_t commonEncodingsArraySectionOffset;
295 // uint32_t commonEncodingsArrayCount;
296 // uint32_t personalityArraySectionOffset;
297 // uint32_t personalityArrayCount;
298 // uint32_t indexSectionOffset;
299 // uint32_t indexCount;
300
301 m_unwind_header.version = m_unwindinfo_data.GetU32(&offset);
302 m_unwind_header.common_encodings_array_offset =
303 m_unwindinfo_data.GetU32(&offset);
304 m_unwind_header.common_encodings_array_count =
305 m_unwindinfo_data.GetU32(&offset);
306 m_unwind_header.personality_array_offset =
307 m_unwindinfo_data.GetU32(&offset);
308 m_unwind_header.personality_array_count = m_unwindinfo_data.GetU32(&offset);
309 uint32_t indexSectionOffset = m_unwindinfo_data.GetU32(&offset);
310
311 uint32_t indexCount = m_unwindinfo_data.GetU32(&offset);
312
313 if (m_unwind_header.common_encodings_array_offset >
314 m_unwindinfo_data.GetByteSize() ||
315 m_unwind_header.personality_array_offset >
316 m_unwindinfo_data.GetByteSize() ||
317 indexSectionOffset > m_unwindinfo_data.GetByteSize() ||
318 offset > m_unwindinfo_data.GetByteSize()) {
319 Host::SystemLog(Host::eSystemLogError, "error: Invalid offset "
320 "encountered in compact unwind "
321 "info, skipping\n");
322 // don't trust anything from this compact_unwind section if it looks
323 // blatantly invalid data in the header.
324 m_indexes_computed = eLazyBoolNo;
325 return;
326 }
327
328 // Parse the basic information from the indexes We wait to scan the second
329 // level page info until it's needed
330
331 // struct unwind_info_section_header_index_entry {
332 // uint32_t functionOffset;
333 // uint32_t secondLevelPagesSectionOffset;
334 // uint32_t lsdaIndexArraySectionOffset;
335 // };
336
337 bool clear_address_zeroth_bit = false;
338 if (ArchSpec arch = m_objfile.GetArchitecture()) {
339 if (arch.GetTriple().getArch() == llvm::Triple::arm ||
340 arch.GetTriple().getArch() == llvm::Triple::thumb)
341 clear_address_zeroth_bit = true;
342 }
343
344 offset = indexSectionOffset;
345 for (uint32_t idx = 0; idx < indexCount; idx++) {
346 uint32_t function_offset =
347 m_unwindinfo_data.GetU32(&offset); // functionOffset
348 uint32_t second_level_offset =
349 m_unwindinfo_data.GetU32(&offset); // secondLevelPagesSectionOffset
350 uint32_t lsda_offset =
351 m_unwindinfo_data.GetU32(&offset); // lsdaIndexArraySectionOffset
352
353 if (second_level_offset > m_section_sp->GetByteSize() ||
354 lsda_offset > m_section_sp->GetByteSize()) {
355 m_indexes_computed = eLazyBoolNo;
356 }
357
358 if (clear_address_zeroth_bit)
359 function_offset &= ~1ull;
360
361 UnwindIndex this_index;
362 this_index.function_offset = function_offset;
363 this_index.second_level = second_level_offset;
364 this_index.lsda_array_start = lsda_offset;
365
366 if (m_indexes.size() > 0) {
367 m_indexes[m_indexes.size() - 1].lsda_array_end = lsda_offset;
368 }
369
370 if (second_level_offset == 0) {
371 this_index.sentinal_entry = true;
372 }
373
374 m_indexes.push_back(this_index);
375 }
376 m_indexes_computed = eLazyBoolYes;
377 } else {
378 m_indexes_computed = eLazyBoolNo;
379 }
380 }
381
382 uint32_t CompactUnwindInfo::GetLSDAForFunctionOffset(uint32_t lsda_offset,
383 uint32_t lsda_count,
384 uint32_t function_offset) {
385 // struct unwind_info_section_header_lsda_index_entry {
386 // uint32_t functionOffset;
387 // uint32_t lsdaOffset;
388 // };
389
390 offset_t first_entry = lsda_offset;
391 uint32_t low = 0;
392 uint32_t high = lsda_count;
393 while (low < high) {
394 uint32_t mid = (low + high) / 2;
395 offset_t offset = first_entry + (mid * 8);
396 uint32_t mid_func_offset =
397 m_unwindinfo_data.GetU32(&offset); // functionOffset
398 uint32_t mid_lsda_offset = m_unwindinfo_data.GetU32(&offset); // lsdaOffset
399 if (mid_func_offset == function_offset) {
400 return mid_lsda_offset;
401 }
402 if (mid_func_offset < function_offset) {
403 low = mid + 1;
404 } else {
405 high = mid;
406 }
407 }
408 return 0;
409 }
410
411 lldb::offset_t CompactUnwindInfo::BinarySearchRegularSecondPage(
412 uint32_t entry_page_offset, uint32_t entry_count, uint32_t function_offset,
413 uint32_t *entry_func_start_offset, uint32_t *entry_func_end_offset) {
414 // typedef uint32_t compact_unwind_encoding_t;
415 // struct unwind_info_regular_second_level_entry {
416 // uint32_t functionOffset;
417 // compact_unwind_encoding_t encoding;
418
419 offset_t first_entry = entry_page_offset;
420
421 uint32_t low = 0;
422 uint32_t high = entry_count;
423 uint32_t last = high - 1;
424 while (low < high) {
425 uint32_t mid = (low + high) / 2;
426 offset_t offset = first_entry + (mid * 8);
427 uint32_t mid_func_offset =
428 m_unwindinfo_data.GetU32(&offset); // functionOffset
429 uint32_t next_func_offset = 0;
430 if (mid < last) {
431 offset = first_entry + ((mid + 1) * 8);
432 next_func_offset = m_unwindinfo_data.GetU32(&offset); // functionOffset
433 }
434 if (mid_func_offset <= function_offset) {
435 if (mid == last || (next_func_offset > function_offset)) {
436 if (entry_func_start_offset)
437 *entry_func_start_offset = mid_func_offset;
438 if (mid != last && entry_func_end_offset)
439 *entry_func_end_offset = next_func_offset;
440 return first_entry + (mid * 8);
441 } else {
442 low = mid + 1;
443 }
444 } else {
445 high = mid;
446 }
447 }
448 return LLDB_INVALID_OFFSET;
449 }
450
451 uint32_t CompactUnwindInfo::BinarySearchCompressedSecondPage(
452 uint32_t entry_page_offset, uint32_t entry_count,
453 uint32_t function_offset_to_find, uint32_t function_offset_base,
454 uint32_t *entry_func_start_offset, uint32_t *entry_func_end_offset) {
455 offset_t first_entry = entry_page_offset;
456
457 uint32_t low = 0;
458 uint32_t high = entry_count;
459 uint32_t last = high - 1;
460 while (low < high) {
461 uint32_t mid = (low + high) / 2;
462 offset_t offset = first_entry + (mid * 4);
463 uint32_t entry = m_unwindinfo_data.GetU32(&offset); // entry
464 uint32_t mid_func_offset = UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(entry);
465 mid_func_offset += function_offset_base;
466 uint32_t next_func_offset = 0;
467 if (mid < last) {
468 offset = first_entry + ((mid + 1) * 4);
469 uint32_t next_entry = m_unwindinfo_data.GetU32(&offset); // entry
470 next_func_offset = UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(next_entry);
471 next_func_offset += function_offset_base;
472 }
473 if (mid_func_offset <= function_offset_to_find) {
474 if (mid == last || (next_func_offset > function_offset_to_find)) {
475 if (entry_func_start_offset)
476 *entry_func_start_offset = mid_func_offset;
477 if (mid != last && entry_func_end_offset)
478 *entry_func_end_offset = next_func_offset;
479 return UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX(entry);
480 } else {
481 low = mid + 1;
482 }
483 } else {
484 high = mid;
485 }
486 }
487
488 return UINT32_MAX;
489 }
490
491 bool CompactUnwindInfo::GetCompactUnwindInfoForFunction(
492 Target &target, Address address, FunctionInfo &unwind_info) {
493 unwind_info.encoding = 0;
494 unwind_info.lsda_address.Clear();
495 unwind_info.personality_ptr_address.Clear();
496
497 if (!IsValid(target.GetProcessSP()))
498 return false;
499
500 addr_t text_section_file_address = LLDB_INVALID_ADDRESS;
501 SectionList *sl = m_objfile.GetSectionList();
502 if (sl) {
503 SectionSP text_sect = sl->FindSectionByType(eSectionTypeCode, true);
504 if (text_sect.get()) {
505 text_section_file_address = text_sect->GetFileAddress();
506 }
507 }
508 if (text_section_file_address == LLDB_INVALID_ADDRESS)
509 return false;
510
511 addr_t function_offset =
512 address.GetFileAddress() - m_objfile.GetBaseAddress().GetFileAddress();
513
514 UnwindIndex key;
515 key.function_offset = function_offset;
516
517 std::vector<UnwindIndex>::const_iterator it;
518 it = std::lower_bound(m_indexes.begin(), m_indexes.end(), key);
519 if (it == m_indexes.end()) {
520 return false;
521 }
522
523 if (it->function_offset != key.function_offset) {
524 if (it != m_indexes.begin())
525 --it;
526 }
527
528 if (it->sentinal_entry) {
529 return false;
530 }
531
532 auto next_it = it + 1;
533 if (next_it != m_indexes.end()) {
534 // initialize the function offset end range to be the start of the next
535 // index offset. If we find an entry which is at the end of the index
536 // table, this will establish the range end.
537 unwind_info.valid_range_offset_end = next_it->function_offset;
538 }
539
540 offset_t second_page_offset = it->second_level;
541 offset_t lsda_array_start = it->lsda_array_start;
542 offset_t lsda_array_count = (it->lsda_array_end - it->lsda_array_start) / 8;
543
544 offset_t offset = second_page_offset;
545 uint32_t kind = m_unwindinfo_data.GetU32(
546 &offset); // UNWIND_SECOND_LEVEL_REGULAR or UNWIND_SECOND_LEVEL_COMPRESSED
547
548 if (kind == UNWIND_SECOND_LEVEL_REGULAR) {
549 // struct unwind_info_regular_second_level_page_header {
550 // uint32_t kind; // UNWIND_SECOND_LEVEL_REGULAR
551 // uint16_t entryPageOffset;
552 // uint16_t entryCount;
553
554 // typedef uint32_t compact_unwind_encoding_t;
555 // struct unwind_info_regular_second_level_entry {
556 // uint32_t functionOffset;
557 // compact_unwind_encoding_t encoding;
558
559 uint16_t entry_page_offset =
560 m_unwindinfo_data.GetU16(&offset); // entryPageOffset
561 uint16_t entry_count = m_unwindinfo_data.GetU16(&offset); // entryCount
562
563 offset_t entry_offset = BinarySearchRegularSecondPage(
564 second_page_offset + entry_page_offset, entry_count, function_offset,
565 &unwind_info.valid_range_offset_start,
566 &unwind_info.valid_range_offset_end);
567 if (entry_offset == LLDB_INVALID_OFFSET) {
568 return false;
569 }
570 entry_offset += 4; // skip over functionOffset
571 unwind_info.encoding = m_unwindinfo_data.GetU32(&entry_offset); // encoding
572 if (unwind_info.encoding & UNWIND_HAS_LSDA) {
573 SectionList *sl = m_objfile.GetSectionList();
574 if (sl) {
575 uint32_t lsda_offset = GetLSDAForFunctionOffset(
576 lsda_array_start, lsda_array_count, function_offset);
577 addr_t objfile_base_address =
578 m_objfile.GetBaseAddress().GetFileAddress();
579 unwind_info.lsda_address.ResolveAddressUsingFileSections(
580 objfile_base_address + lsda_offset, sl);
581 }
582 }
583 if (unwind_info.encoding & UNWIND_PERSONALITY_MASK) {
584 uint32_t personality_index =
585 EXTRACT_BITS(unwind_info.encoding, UNWIND_PERSONALITY_MASK);
586
587 if (personality_index > 0) {
588 personality_index--;
589 if (personality_index < m_unwind_header.personality_array_count) {
590 offset_t offset = m_unwind_header.personality_array_offset;
591 offset += 4 * personality_index;
592 SectionList *sl = m_objfile.GetSectionList();
593 if (sl) {
594 uint32_t personality_offset = m_unwindinfo_data.GetU32(&offset);
595 addr_t objfile_base_address =
596 m_objfile.GetBaseAddress().GetFileAddress();
597 unwind_info.personality_ptr_address.ResolveAddressUsingFileSections(
598 objfile_base_address + personality_offset, sl);
599 }
600 }
601 }
602 }
603 return true;
604 } else if (kind == UNWIND_SECOND_LEVEL_COMPRESSED) {
605 // struct unwind_info_compressed_second_level_page_header {
606 // uint32_t kind; // UNWIND_SECOND_LEVEL_COMPRESSED
607 // uint16_t entryPageOffset; // offset from this 2nd lvl page
608 // idx to array of entries
609 // // (an entry has a function
610 // offset and index into the
611 // encodings)
612 // // NB function offset from the
613 // entry in the compressed page
614 // // must be added to the index's
615 // functionOffset value.
616 // uint16_t entryCount;
617 // uint16_t encodingsPageOffset; // offset from this 2nd lvl page
618 // idx to array of encodings
619 // uint16_t encodingsCount;
620
621 uint16_t entry_page_offset =
622 m_unwindinfo_data.GetU16(&offset); // entryPageOffset
623 uint16_t entry_count = m_unwindinfo_data.GetU16(&offset); // entryCount
624 uint16_t encodings_page_offset =
625 m_unwindinfo_data.GetU16(&offset); // encodingsPageOffset
626 uint16_t encodings_count =
627 m_unwindinfo_data.GetU16(&offset); // encodingsCount
628
629 uint32_t encoding_index = BinarySearchCompressedSecondPage(
630 second_page_offset + entry_page_offset, entry_count, function_offset,
631 it->function_offset, &unwind_info.valid_range_offset_start,
632 &unwind_info.valid_range_offset_end);
633 if (encoding_index == UINT32_MAX ||
634 encoding_index >=
635 encodings_count + m_unwind_header.common_encodings_array_count) {
636 return false;
637 }
638 uint32_t encoding = 0;
639 if (encoding_index < m_unwind_header.common_encodings_array_count) {
640 offset = m_unwind_header.common_encodings_array_offset +
641 (encoding_index * sizeof(uint32_t));
642 encoding = m_unwindinfo_data.GetU32(
643 &offset); // encoding entry from the commonEncodingsArray
644 } else {
645 uint32_t page_specific_entry_index =
646 encoding_index - m_unwind_header.common_encodings_array_count;
647 offset = second_page_offset + encodings_page_offset +
648 (page_specific_entry_index * sizeof(uint32_t));
649 encoding = m_unwindinfo_data.GetU32(
650 &offset); // encoding entry from the page-specific encoding array
651 }
652 if (encoding == 0)
653 return false;
654
655 unwind_info.encoding = encoding;
656 if (unwind_info.encoding & UNWIND_HAS_LSDA) {
657 SectionList *sl = m_objfile.GetSectionList();
658 if (sl) {
659 uint32_t lsda_offset = GetLSDAForFunctionOffset(
660 lsda_array_start, lsda_array_count, function_offset);
661 addr_t objfile_base_address =
662 m_objfile.GetBaseAddress().GetFileAddress();
663 unwind_info.lsda_address.ResolveAddressUsingFileSections(
664 objfile_base_address + lsda_offset, sl);
665 }
666 }
667 if (unwind_info.encoding & UNWIND_PERSONALITY_MASK) {
668 uint32_t personality_index =
669 EXTRACT_BITS(unwind_info.encoding, UNWIND_PERSONALITY_MASK);
670
671 if (personality_index > 0) {
672 personality_index--;
673 if (personality_index < m_unwind_header.personality_array_count) {
674 offset_t offset = m_unwind_header.personality_array_offset;
675 offset += 4 * personality_index;
676 SectionList *sl = m_objfile.GetSectionList();
677 if (sl) {
678 uint32_t personality_offset = m_unwindinfo_data.GetU32(&offset);
679 addr_t objfile_base_address =
680 m_objfile.GetBaseAddress().GetFileAddress();
681 unwind_info.personality_ptr_address.ResolveAddressUsingFileSections(
682 objfile_base_address + personality_offset, sl);
683 }
684 }
685 }
686 }
687 return true;
688 }
689 return false;
690 }
691
692 enum x86_64_eh_regnum {
693 rax = 0,
694 rdx = 1,
695 rcx = 2,
696 rbx = 3,
697 rsi = 4,
698 rdi = 5,
699 rbp = 6,
700 rsp = 7,
701 r8 = 8,
702 r9 = 9,
703 r10 = 10,
704 r11 = 11,
705 r12 = 12,
706 r13 = 13,
707 r14 = 14,
708 r15 = 15,
709 rip = 16 // this is officially the Return Address register number, but close
710 // enough
711 };
712
713 // Convert the compact_unwind_info.h register numbering scheme to
714 // eRegisterKindEHFrame (eh_frame) register numbering scheme.
715 uint32_t translate_to_eh_frame_regnum_x86_64(uint32_t unwind_regno) {
716 switch (unwind_regno) {
717 case UNWIND_X86_64_REG_RBX:
718 return x86_64_eh_regnum::rbx;
719 case UNWIND_X86_64_REG_R12:
720 return x86_64_eh_regnum::r12;
721 case UNWIND_X86_64_REG_R13:
722 return x86_64_eh_regnum::r13;
723 case UNWIND_X86_64_REG_R14:
724 return x86_64_eh_regnum::r14;
725 case UNWIND_X86_64_REG_R15:
726 return x86_64_eh_regnum::r15;
727 case UNWIND_X86_64_REG_RBP:
728 return x86_64_eh_regnum::rbp;
729 default:
730 return LLDB_INVALID_REGNUM;
731 }
732 }
733
734 bool CompactUnwindInfo::CreateUnwindPlan_x86_64(Target &target,
735 FunctionInfo &function_info,
736 UnwindPlan &unwind_plan,
737 Address pc_or_function_start) {
738 unwind_plan.SetSourceName("compact unwind info");
739 unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
740 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
741 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
742 unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
743
744 unwind_plan.SetLSDAAddress(function_info.lsda_address);
745 unwind_plan.SetPersonalityFunctionPtr(function_info.personality_ptr_address);
746
747 UnwindPlan::RowSP row(new UnwindPlan::Row);
748
749 const int wordsize = 8;
750 int mode = function_info.encoding & UNWIND_X86_64_MODE_MASK;
751 switch (mode) {
752 case UNWIND_X86_64_MODE_RBP_FRAME: {
753 row->GetCFAValue().SetIsRegisterPlusOffset(
754 translate_to_eh_frame_regnum_x86_64(UNWIND_X86_64_REG_RBP),
755 2 * wordsize);
756 row->SetOffset(0);
757 row->SetRegisterLocationToAtCFAPlusOffset(x86_64_eh_regnum::rbp,
758 wordsize * -2, true);
759 row->SetRegisterLocationToAtCFAPlusOffset(x86_64_eh_regnum::rip,
760 wordsize * -1, true);
761 row->SetRegisterLocationToIsCFAPlusOffset(x86_64_eh_regnum::rsp, 0, true);
762
763 uint32_t saved_registers_offset =
764 EXTRACT_BITS(function_info.encoding, UNWIND_X86_64_RBP_FRAME_OFFSET);
765
766 uint32_t saved_registers_locations =
767 EXTRACT_BITS(function_info.encoding, UNWIND_X86_64_RBP_FRAME_REGISTERS);
768
769 saved_registers_offset += 2;
770
771 for (int i = 0; i < 5; i++) {
772 uint32_t regnum = saved_registers_locations & 0x7;
773 switch (regnum) {
774 case UNWIND_X86_64_REG_NONE:
775 break;
776 case UNWIND_X86_64_REG_RBX:
777 case UNWIND_X86_64_REG_R12:
778 case UNWIND_X86_64_REG_R13:
779 case UNWIND_X86_64_REG_R14:
780 case UNWIND_X86_64_REG_R15:
781 row->SetRegisterLocationToAtCFAPlusOffset(
782 translate_to_eh_frame_regnum_x86_64(regnum),
783 wordsize * -saved_registers_offset, true);
784 break;
785 }
786 saved_registers_offset--;
787 saved_registers_locations >>= 3;
788 }
789 unwind_plan.AppendRow(row);
790 return true;
791 } break;
792
793 case UNWIND_X86_64_MODE_STACK_IND: {
794 // The clang in Xcode 6 is emitting incorrect compact unwind encodings for
795 // this style of unwind. It was fixed in llvm r217020. The clang in Xcode
796 // 7 has this fixed.
797 return false;
798 } break;
799
800 case UNWIND_X86_64_MODE_STACK_IMMD: {
801 uint32_t stack_size = EXTRACT_BITS(function_info.encoding,
802 UNWIND_X86_64_FRAMELESS_STACK_SIZE);
803 uint32_t register_count = EXTRACT_BITS(
804 function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_REG_COUNT);
805 uint32_t permutation = EXTRACT_BITS(
806 function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_REG_PERMUTATION);
807
808 if (mode == UNWIND_X86_64_MODE_STACK_IND &&
809 function_info.valid_range_offset_start != 0) {
810 uint32_t stack_adjust = EXTRACT_BITS(
811 function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_ADJUST);
812
813 // offset into the function instructions; 0 == beginning of first
814 // instruction
815 uint32_t offset_to_subl_insn = EXTRACT_BITS(
816 function_info.encoding, UNWIND_X86_64_FRAMELESS_STACK_SIZE);
817
818 SectionList *sl = m_objfile.GetSectionList();
819 if (sl) {
820 ProcessSP process_sp = target.GetProcessSP();
821 if (process_sp) {
822 Address subl_payload_addr(function_info.valid_range_offset_start, sl);
823 subl_payload_addr.Slide(offset_to_subl_insn);
824 Status error;
825 uint64_t large_stack_size = process_sp->ReadUnsignedIntegerFromMemory(
826 subl_payload_addr.GetLoadAddress(&target), 4, 0, error);
827 if (large_stack_size != 0 && error.Success()) {
828 // Got the large stack frame size correctly - use it
829 stack_size = large_stack_size + (stack_adjust * wordsize);
830 } else {
831 return false;
832 }
833 } else {
834 return false;
835 }
836 } else {
837 return false;
838 }
839 }
840
841 int32_t offset = mode == UNWIND_X86_64_MODE_STACK_IND
842 ? stack_size
843 : stack_size * wordsize;
844 row->GetCFAValue().SetIsRegisterPlusOffset(x86_64_eh_regnum::rsp, offset);
845
846 row->SetOffset(0);
847 row->SetRegisterLocationToAtCFAPlusOffset(x86_64_eh_regnum::rip,
848 wordsize * -1, true);
849 row->SetRegisterLocationToIsCFAPlusOffset(x86_64_eh_regnum::rsp, 0, true);
850
851 if (register_count > 0) {
852
853 // We need to include (up to) 6 registers in 10 bits. That would be 18
854 // bits if we just used 3 bits per reg to indicate the order they're
855 // saved on the stack.
856 //
857 // This is done with Lehmer code permutation, e.g. see
858 // http://stackoverflow.com/questions/1506078/fast-permutation-number-
859 // permutation-mapping-algorithms
860 int permunreg[6] = {0, 0, 0, 0, 0, 0};
861
862 // This decodes the variable-base number in the 10 bits and gives us the
863 // Lehmer code sequence which can then be decoded.
864
865 switch (register_count) {
866 case 6:
867 permunreg[0] = permutation / 120; // 120 == 5!
868 permutation -= (permunreg[0] * 120);
869 permunreg[1] = permutation / 24; // 24 == 4!
870 permutation -= (permunreg[1] * 24);
871 permunreg[2] = permutation / 6; // 6 == 3!
872 permutation -= (permunreg[2] * 6);
873 permunreg[3] = permutation / 2; // 2 == 2!
874 permutation -= (permunreg[3] * 2);
875 permunreg[4] = permutation; // 1 == 1!
876 permunreg[5] = 0;
877 break;
878 case 5:
879 permunreg[0] = permutation / 120;
880 permutation -= (permunreg[0] * 120);
881 permunreg[1] = permutation / 24;
882 permutation -= (permunreg[1] * 24);
883 permunreg[2] = permutation / 6;
884 permutation -= (permunreg[2] * 6);
885 permunreg[3] = permutation / 2;
886 permutation -= (permunreg[3] * 2);
887 permunreg[4] = permutation;
888 break;
889 case 4:
890 permunreg[0] = permutation / 60;
891 permutation -= (permunreg[0] * 60);
892 permunreg[1] = permutation / 12;
893 permutation -= (permunreg[1] * 12);
894 permunreg[2] = permutation / 3;
895 permutation -= (permunreg[2] * 3);
896 permunreg[3] = permutation;
897 break;
898 case 3:
899 permunreg[0] = permutation / 20;
900 permutation -= (permunreg[0] * 20);
901 permunreg[1] = permutation / 4;
902 permutation -= (permunreg[1] * 4);
903 permunreg[2] = permutation;
904 break;
905 case 2:
906 permunreg[0] = permutation / 5;
907 permutation -= (permunreg[0] * 5);
908 permunreg[1] = permutation;
909 break;
910 case 1:
911 permunreg[0] = permutation;
912 break;
913 }
914
915 // Decode the Lehmer code for this permutation of the registers v.
916 // http://en.wikipedia.org/wiki/Lehmer_code
917
918 int registers[6] = {UNWIND_X86_64_REG_NONE, UNWIND_X86_64_REG_NONE,
919 UNWIND_X86_64_REG_NONE, UNWIND_X86_64_REG_NONE,
920 UNWIND_X86_64_REG_NONE, UNWIND_X86_64_REG_NONE};
921 bool used[7] = {false, false, false, false, false, false, false};
922 for (uint32_t i = 0; i < register_count; i++) {
923 int renum = 0;
924 for (int j = 1; j < 7; j++) {
925 if (!used[j]) {
926 if (renum == permunreg[i]) {
927 registers[i] = j;
928 used[j] = true;
929 break;
930 }
931 renum++;
932 }
933 }
934 }
935
936 uint32_t saved_registers_offset = 1;
937 saved_registers_offset++;
938
939 for (int i = (sizeof(registers) / sizeof(int)) - 1; i >= 0; i--) {
940 switch (registers[i]) {
941 case UNWIND_X86_64_REG_NONE:
942 break;
943 case UNWIND_X86_64_REG_RBX:
944 case UNWIND_X86_64_REG_R12:
945 case UNWIND_X86_64_REG_R13:
946 case UNWIND_X86_64_REG_R14:
947 case UNWIND_X86_64_REG_R15:
948 case UNWIND_X86_64_REG_RBP:
949 row->SetRegisterLocationToAtCFAPlusOffset(
950 translate_to_eh_frame_regnum_x86_64(registers[i]),
951 wordsize * -saved_registers_offset, true);
952 saved_registers_offset++;
953 break;
954 }
955 }
956 }
957 unwind_plan.AppendRow(row);
958 return true;
959 } break;
960
961 case UNWIND_X86_64_MODE_DWARF: {
962 return false;
963 } break;
964
965 case 0: {
966 return false;
967 } break;
968 }
969 return false;
970 }
971
972 enum i386_eh_regnum {
973 eax = 0,
974 ecx = 1,
975 edx = 2,
976 ebx = 3,
977 ebp = 4,
978 esp = 5,
979 esi = 6,
980 edi = 7,
981 eip = 8 // this is officially the Return Address register number, but close
982 // enough
983 };
984
985 // Convert the compact_unwind_info.h register numbering scheme to
986 // eRegisterKindEHFrame (eh_frame) register numbering scheme.
987 uint32_t translate_to_eh_frame_regnum_i386(uint32_t unwind_regno) {
988 switch (unwind_regno) {
989 case UNWIND_X86_REG_EBX:
990 return i386_eh_regnum::ebx;
991 case UNWIND_X86_REG_ECX:
992 return i386_eh_regnum::ecx;
993 case UNWIND_X86_REG_EDX:
994 return i386_eh_regnum::edx;
995 case UNWIND_X86_REG_EDI:
996 return i386_eh_regnum::edi;
997 case UNWIND_X86_REG_ESI:
998 return i386_eh_regnum::esi;
999 case UNWIND_X86_REG_EBP:
1000 return i386_eh_regnum::ebp;
1001 default:
1002 return LLDB_INVALID_REGNUM;
1003 }
1004 }
1005
1006 bool CompactUnwindInfo::CreateUnwindPlan_i386(Target &target,
1007 FunctionInfo &function_info,
1008 UnwindPlan &unwind_plan,
1009 Address pc_or_function_start) {
1010 unwind_plan.SetSourceName("compact unwind info");
1011 unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
1012 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
1013 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
1014 unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
1015
1016 unwind_plan.SetLSDAAddress(function_info.lsda_address);
1017 unwind_plan.SetPersonalityFunctionPtr(function_info.personality_ptr_address);
1018
1019 UnwindPlan::RowSP row(new UnwindPlan::Row);
1020
1021 const int wordsize = 4;
1022 int mode = function_info.encoding & UNWIND_X86_MODE_MASK;
1023 switch (mode) {
1024 case UNWIND_X86_MODE_EBP_FRAME: {
1025 row->GetCFAValue().SetIsRegisterPlusOffset(
1026 translate_to_eh_frame_regnum_i386(UNWIND_X86_REG_EBP), 2 * wordsize);
1027 row->SetOffset(0);
1028 row->SetRegisterLocationToAtCFAPlusOffset(i386_eh_regnum::ebp,
1029 wordsize * -2, true);
1030 row->SetRegisterLocationToAtCFAPlusOffset(i386_eh_regnum::eip,
1031 wordsize * -1, true);
1032 row->SetRegisterLocationToIsCFAPlusOffset(i386_eh_regnum::esp, 0, true);
1033
1034 uint32_t saved_registers_offset =
1035 EXTRACT_BITS(function_info.encoding, UNWIND_X86_EBP_FRAME_OFFSET);
1036
1037 uint32_t saved_registers_locations =
1038 EXTRACT_BITS(function_info.encoding, UNWIND_X86_EBP_FRAME_REGISTERS);
1039
1040 saved_registers_offset += 2;
1041
1042 for (int i = 0; i < 5; i++) {
1043 uint32_t regnum = saved_registers_locations & 0x7;
1044 switch (regnum) {
1045 case UNWIND_X86_REG_NONE:
1046 break;
1047 case UNWIND_X86_REG_EBX:
1048 case UNWIND_X86_REG_ECX:
1049 case UNWIND_X86_REG_EDX:
1050 case UNWIND_X86_REG_EDI:
1051 case UNWIND_X86_REG_ESI:
1052 row->SetRegisterLocationToAtCFAPlusOffset(
1053 translate_to_eh_frame_regnum_i386(regnum),
1054 wordsize * -saved_registers_offset, true);
1055 break;
1056 }
1057 saved_registers_offset--;
1058 saved_registers_locations >>= 3;
1059 }
1060 unwind_plan.AppendRow(row);
1061 return true;
1062 } break;
1063
1064 case UNWIND_X86_MODE_STACK_IND:
1065 case UNWIND_X86_MODE_STACK_IMMD: {
1066 uint32_t stack_size =
1067 EXTRACT_BITS(function_info.encoding, UNWIND_X86_FRAMELESS_STACK_SIZE);
1068 uint32_t register_count = EXTRACT_BITS(
1069 function_info.encoding, UNWIND_X86_FRAMELESS_STACK_REG_COUNT);
1070 uint32_t permutation = EXTRACT_BITS(
1071 function_info.encoding, UNWIND_X86_FRAMELESS_STACK_REG_PERMUTATION);
1072
1073 if (mode == UNWIND_X86_MODE_STACK_IND &&
1074 function_info.valid_range_offset_start != 0) {
1075 uint32_t stack_adjust = EXTRACT_BITS(function_info.encoding,
1076 UNWIND_X86_FRAMELESS_STACK_ADJUST);
1077
1078 // offset into the function instructions; 0 == beginning of first
1079 // instruction
1080 uint32_t offset_to_subl_insn =
1081 EXTRACT_BITS(function_info.encoding, UNWIND_X86_FRAMELESS_STACK_SIZE);
1082
1083 SectionList *sl = m_objfile.GetSectionList();
1084 if (sl) {
1085 ProcessSP process_sp = target.GetProcessSP();
1086 if (process_sp) {
1087 Address subl_payload_addr(function_info.valid_range_offset_start, sl);
1088 subl_payload_addr.Slide(offset_to_subl_insn);
1089 Status error;
1090 uint64_t large_stack_size = process_sp->ReadUnsignedIntegerFromMemory(
1091 subl_payload_addr.GetLoadAddress(&target), 4, 0, error);
1092 if (large_stack_size != 0 && error.Success()) {
1093 // Got the large stack frame size correctly - use it
1094 stack_size = large_stack_size + (stack_adjust * wordsize);
1095 } else {
1096 return false;
1097 }
1098 } else {
1099 return false;
1100 }
1101 } else {
1102 return false;
1103 }
1104 }
1105
1106 int32_t offset =
1107 mode == UNWIND_X86_MODE_STACK_IND ? stack_size : stack_size * wordsize;
1108 row->GetCFAValue().SetIsRegisterPlusOffset(i386_eh_regnum::esp, offset);
1109 row->SetOffset(0);
1110 row->SetRegisterLocationToAtCFAPlusOffset(i386_eh_regnum::eip,
1111 wordsize * -1, true);
1112 row->SetRegisterLocationToIsCFAPlusOffset(i386_eh_regnum::esp, 0, true);
1113
1114 if (register_count > 0) {
1115
1116 // We need to include (up to) 6 registers in 10 bits. That would be 18
1117 // bits if we just used 3 bits per reg to indicate the order they're
1118 // saved on the stack.
1119 //
1120 // This is done with Lehmer code permutation, e.g. see
1121 // http://stackoverflow.com/questions/1506078/fast-permutation-number-
1122 // permutation-mapping-algorithms
1123 int permunreg[6] = {0, 0, 0, 0, 0, 0};
1124
1125 // This decodes the variable-base number in the 10 bits and gives us the
1126 // Lehmer code sequence which can then be decoded.
1127
1128 switch (register_count) {
1129 case 6:
1130 permunreg[0] = permutation / 120; // 120 == 5!
1131 permutation -= (permunreg[0] * 120);
1132 permunreg[1] = permutation / 24; // 24 == 4!
1133 permutation -= (permunreg[1] * 24);
1134 permunreg[2] = permutation / 6; // 6 == 3!
1135 permutation -= (permunreg[2] * 6);
1136 permunreg[3] = permutation / 2; // 2 == 2!
1137 permutation -= (permunreg[3] * 2);
1138 permunreg[4] = permutation; // 1 == 1!
1139 permunreg[5] = 0;
1140 break;
1141 case 5:
1142 permunreg[0] = permutation / 120;
1143 permutation -= (permunreg[0] * 120);
1144 permunreg[1] = permutation / 24;
1145 permutation -= (permunreg[1] * 24);
1146 permunreg[2] = permutation / 6;
1147 permutation -= (permunreg[2] * 6);
1148 permunreg[3] = permutation / 2;
1149 permutation -= (permunreg[3] * 2);
1150 permunreg[4] = permutation;
1151 break;
1152 case 4:
1153 permunreg[0] = permutation / 60;
1154 permutation -= (permunreg[0] * 60);
1155 permunreg[1] = permutation / 12;
1156 permutation -= (permunreg[1] * 12);
1157 permunreg[2] = permutation / 3;
1158 permutation -= (permunreg[2] * 3);
1159 permunreg[3] = permutation;
1160 break;
1161 case 3:
1162 permunreg[0] = permutation / 20;
1163 permutation -= (permunreg[0] * 20);
1164 permunreg[1] = permutation / 4;
1165 permutation -= (permunreg[1] * 4);
1166 permunreg[2] = permutation;
1167 break;
1168 case 2:
1169 permunreg[0] = permutation / 5;
1170 permutation -= (permunreg[0] * 5);
1171 permunreg[1] = permutation;
1172 break;
1173 case 1:
1174 permunreg[0] = permutation;
1175 break;
1176 }
1177
1178 // Decode the Lehmer code for this permutation of the registers v.
1179 // http://en.wikipedia.org/wiki/Lehmer_code
1180
1181 int registers[6] = {UNWIND_X86_REG_NONE, UNWIND_X86_REG_NONE,
1182 UNWIND_X86_REG_NONE, UNWIND_X86_REG_NONE,
1183 UNWIND_X86_REG_NONE, UNWIND_X86_REG_NONE};
1184 bool used[7] = {false, false, false, false, false, false, false};
1185 for (uint32_t i = 0; i < register_count; i++) {
1186 int renum = 0;
1187 for (int j = 1; j < 7; j++) {
1188 if (!used[j]) {
1189 if (renum == permunreg[i]) {
1190 registers[i] = j;
1191 used[j] = true;
1192 break;
1193 }
1194 renum++;
1195 }
1196 }
1197 }
1198
1199 uint32_t saved_registers_offset = 1;
1200 saved_registers_offset++;
1201
1202 for (int i = (sizeof(registers) / sizeof(int)) - 1; i >= 0; i--) {
1203 switch (registers[i]) {
1204 case UNWIND_X86_REG_NONE:
1205 break;
1206 case UNWIND_X86_REG_EBX:
1207 case UNWIND_X86_REG_ECX:
1208 case UNWIND_X86_REG_EDX:
1209 case UNWIND_X86_REG_EDI:
1210 case UNWIND_X86_REG_ESI:
1211 case UNWIND_X86_REG_EBP:
1212 row->SetRegisterLocationToAtCFAPlusOffset(
1213 translate_to_eh_frame_regnum_i386(registers[i]),
1214 wordsize * -saved_registers_offset, true);
1215 saved_registers_offset++;
1216 break;
1217 }
1218 }
1219 }
1220
1221 unwind_plan.AppendRow(row);
1222 return true;
1223 } break;
1224
1225 case UNWIND_X86_MODE_DWARF: {
1226 return false;
1227 } break;
1228 }
1229 return false;
1230 }
1231
1232 // DWARF register numbers from "DWARF for the ARM 64-bit Architecture (AArch64)"
1233 // doc by ARM
1234
1235 enum arm64_eh_regnum {
1236 x19 = 19,
1237 x20 = 20,
1238 x21 = 21,
1239 x22 = 22,
1240 x23 = 23,
1241 x24 = 24,
1242 x25 = 25,
1243 x26 = 26,
1244 x27 = 27,
1245 x28 = 28,
1246
1247 fp = 29,
1248 ra = 30,
1249 sp = 31,
1250 pc = 32,
1251
1252 // Compact unwind encodes d8-d15 but we don't have eh_frame / dwarf reg #'s
1253 // for the 64-bit fp regs. Normally in DWARF it's context sensitive - so it
1254 // knows it is fetching a 32- or 64-bit quantity from reg v8 to indicate s0
1255 // or d0 - but the unwinder is operating at a lower level and we'd try to
1256 // fetch 128 bits if we were told that v8 were stored on the stack...
1257 v8 = 72,
1258 v9 = 73,
1259 v10 = 74,
1260 v11 = 75,
1261 v12 = 76,
1262 v13 = 77,
1263 v14 = 78,
1264 v15 = 79,
1265 };
1266
1267 enum arm_eh_regnum {
1268 arm_r0 = 0,
1269 arm_r1 = 1,
1270 arm_r2 = 2,
1271 arm_r3 = 3,
1272 arm_r4 = 4,
1273 arm_r5 = 5,
1274 arm_r6 = 6,
1275 arm_r7 = 7,
1276 arm_r8 = 8,
1277 arm_r9 = 9,
1278 arm_r10 = 10,
1279 arm_r11 = 11,
1280 arm_r12 = 12,
1281
1282 arm_sp = 13,
1283 arm_lr = 14,
1284 arm_pc = 15,
1285
1286 arm_d0 = 256,
1287 arm_d1 = 257,
1288 arm_d2 = 258,
1289 arm_d3 = 259,
1290 arm_d4 = 260,
1291 arm_d5 = 261,
1292 arm_d6 = 262,
1293 arm_d7 = 263,
1294 arm_d8 = 264,
1295 arm_d9 = 265,
1296 arm_d10 = 266,
1297 arm_d11 = 267,
1298 arm_d12 = 268,
1299 arm_d13 = 269,
1300 arm_d14 = 270,
1301 };
1302
1303 bool CompactUnwindInfo::CreateUnwindPlan_arm64(Target &target,
1304 FunctionInfo &function_info,
1305 UnwindPlan &unwind_plan,
1306 Address pc_or_function_start) {
1307 unwind_plan.SetSourceName("compact unwind info");
1308 unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
1309 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
1310 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
1311 unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
1312
1313 unwind_plan.SetLSDAAddress(function_info.lsda_address);
1314 unwind_plan.SetPersonalityFunctionPtr(function_info.personality_ptr_address);
1315
1316 UnwindPlan::RowSP row(new UnwindPlan::Row);
1317
1318 const int wordsize = 8;
1319 int mode = function_info.encoding & UNWIND_ARM64_MODE_MASK;
1320
1321 if (mode == UNWIND_ARM64_MODE_DWARF)
1322 return false;
1323
1324 if (mode == UNWIND_ARM64_MODE_FRAMELESS) {
1325 row->SetOffset(0);
1326
1327 uint32_t stack_size =
1328 (EXTRACT_BITS(function_info.encoding,
1329 UNWIND_ARM64_FRAMELESS_STACK_SIZE_MASK)) *
1330 16;
1331
1332 // Our previous Call Frame Address is the stack pointer plus the stack size
1333 row->GetCFAValue().SetIsRegisterPlusOffset(arm64_eh_regnum::sp, stack_size);
1334
1335 // Our previous PC is in the LR
1336 row->SetRegisterLocationToRegister(arm64_eh_regnum::pc, arm64_eh_regnum::ra,
1337 true);
1338
1339 unwind_plan.AppendRow(row);
1340 return true;
1341 }
1342
1343 // Should not be possible
1344 if (mode != UNWIND_ARM64_MODE_FRAME)
1345 return false;
1346
1347 // mode == UNWIND_ARM64_MODE_FRAME
1348
1349 row->GetCFAValue().SetIsRegisterPlusOffset(arm64_eh_regnum::fp, 2 * wordsize);
1350 row->SetOffset(0);
1351 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::fp, wordsize * -2,
1352 true);
1353 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::pc, wordsize * -1,
1354 true);
1355 row->SetRegisterLocationToIsCFAPlusOffset(arm64_eh_regnum::sp, 0, true);
1356
1357 int reg_pairs_saved_count = 1;
1358
1359 uint32_t saved_register_bits = function_info.encoding & 0xfff;
1360
1361 if (saved_register_bits & UNWIND_ARM64_FRAME_X19_X20_PAIR) {
1362 int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
1363 cfa_offset -= wordsize;
1364 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x19, cfa_offset,
1365 true);
1366 cfa_offset -= wordsize;
1367 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x20, cfa_offset,
1368 true);
1369 reg_pairs_saved_count++;
1370 }
1371
1372 if (saved_register_bits & UNWIND_ARM64_FRAME_X21_X22_PAIR) {
1373 int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
1374 cfa_offset -= wordsize;
1375 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x21, cfa_offset,
1376 true);
1377 cfa_offset -= wordsize;
1378 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x22, cfa_offset,
1379 true);
1380 reg_pairs_saved_count++;
1381 }
1382
1383 if (saved_register_bits & UNWIND_ARM64_FRAME_X23_X24_PAIR) {
1384 int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
1385 cfa_offset -= wordsize;
1386 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x23, cfa_offset,
1387 true);
1388 cfa_offset -= wordsize;
1389 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x24, cfa_offset,
1390 true);
1391 reg_pairs_saved_count++;
1392 }
1393
1394 if (saved_register_bits & UNWIND_ARM64_FRAME_X25_X26_PAIR) {
1395 int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
1396 cfa_offset -= wordsize;
1397 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x25, cfa_offset,
1398 true);
1399 cfa_offset -= wordsize;
1400 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x26, cfa_offset,
1401 true);
1402 reg_pairs_saved_count++;
1403 }
1404
1405 if (saved_register_bits & UNWIND_ARM64_FRAME_X27_X28_PAIR) {
1406 int cfa_offset = reg_pairs_saved_count * -2 * wordsize;
1407 cfa_offset -= wordsize;
1408 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x27, cfa_offset,
1409 true);
1410 cfa_offset -= wordsize;
1411 row->SetRegisterLocationToAtCFAPlusOffset(arm64_eh_regnum::x28, cfa_offset,
1412 true);
1413 reg_pairs_saved_count++;
1414 }
1415
1416 // If we use the v8-v15 regnums here, the unwinder will try to grab 128 bits
1417 // off the stack;
1418 // not sure if we have a good way to represent the 64-bitness of these saves.
1419
1420 if (saved_register_bits & UNWIND_ARM64_FRAME_D8_D9_PAIR) {
1421 reg_pairs_saved_count++;
1422 }
1423 if (saved_register_bits & UNWIND_ARM64_FRAME_D10_D11_PAIR) {
1424 reg_pairs_saved_count++;
1425 }
1426 if (saved_register_bits & UNWIND_ARM64_FRAME_D12_D13_PAIR) {
1427 reg_pairs_saved_count++;
1428 }
1429 if (saved_register_bits & UNWIND_ARM64_FRAME_D14_D15_PAIR) {
1430 reg_pairs_saved_count++;
1431 }
1432
1433 unwind_plan.AppendRow(row);
1434 return true;
1435 }
1436
1437 bool CompactUnwindInfo::CreateUnwindPlan_armv7(Target &target,
1438 FunctionInfo &function_info,
1439 UnwindPlan &unwind_plan,
1440 Address pc_or_function_start) {
1441 unwind_plan.SetSourceName("compact unwind info");
1442 unwind_plan.SetSourcedFromCompiler(eLazyBoolYes);
1443 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
1444 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
1445 unwind_plan.SetRegisterKind(eRegisterKindEHFrame);
1446
1447 unwind_plan.SetLSDAAddress(function_info.lsda_address);
1448 unwind_plan.SetPersonalityFunctionPtr(function_info.personality_ptr_address);
1449
1450 UnwindPlan::RowSP row(new UnwindPlan::Row);
1451
1452 const int wordsize = 4;
1453 int mode = function_info.encoding & UNWIND_ARM_MODE_MASK;
1454
1455 if (mode == UNWIND_ARM_MODE_DWARF)
1456 return false;
1457
1458 uint32_t stack_adjust = (EXTRACT_BITS(function_info.encoding,
1459 UNWIND_ARM_FRAME_STACK_ADJUST_MASK)) *
1460 wordsize;
1461
1462 row->GetCFAValue().SetIsRegisterPlusOffset(arm_r7,
1463 (2 * wordsize) + stack_adjust);
1464 row->SetOffset(0);
1465 row->SetRegisterLocationToAtCFAPlusOffset(
1466 arm_r7, (wordsize * -2) - stack_adjust, true);
1467 row->SetRegisterLocationToAtCFAPlusOffset(
1468 arm_pc, (wordsize * -1) - stack_adjust, true);
1469 row->SetRegisterLocationToIsCFAPlusOffset(arm_sp, 0, true);
1470
1471 int cfa_offset = -stack_adjust - (2 * wordsize);
1472
1473 uint32_t saved_register_bits = function_info.encoding & 0xff;
1474
1475 if (saved_register_bits & UNWIND_ARM_FRAME_FIRST_PUSH_R6) {
1476 cfa_offset -= wordsize;
1477 row->SetRegisterLocationToAtCFAPlusOffset(arm_r6, cfa_offset, true);
1478 }
1479
1480 if (saved_register_bits & UNWIND_ARM_FRAME_FIRST_PUSH_R5) {
1481 cfa_offset -= wordsize;
1482 row->SetRegisterLocationToAtCFAPlusOffset(arm_r5, cfa_offset, true);
1483 }
1484
1485 if (saved_register_bits & UNWIND_ARM_FRAME_FIRST_PUSH_R4) {
1486 cfa_offset -= wordsize;
1487 row->SetRegisterLocationToAtCFAPlusOffset(arm_r4, cfa_offset, true);
1488 }
1489
1490 if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R12) {
1491 cfa_offset -= wordsize;
1492 row->SetRegisterLocationToAtCFAPlusOffset(arm_r12, cfa_offset, true);
1493 }
1494
1495 if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R11) {
1496 cfa_offset -= wordsize;
1497 row->SetRegisterLocationToAtCFAPlusOffset(arm_r11, cfa_offset, true);
1498 }
1499
1500 if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R10) {
1501 cfa_offset -= wordsize;
1502 row->SetRegisterLocationToAtCFAPlusOffset(arm_r10, cfa_offset, true);
1503 }
1504
1505 if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R9) {
1506 cfa_offset -= wordsize;
1507 row->SetRegisterLocationToAtCFAPlusOffset(arm_r9, cfa_offset, true);
1508 }
1509
1510 if (saved_register_bits & UNWIND_ARM_FRAME_SECOND_PUSH_R8) {
1511 cfa_offset -= wordsize;
1512 row->SetRegisterLocationToAtCFAPlusOffset(arm_r8, cfa_offset, true);
1513 }
1514
1515 if (mode == UNWIND_ARM_MODE_FRAME_D) {
1516 uint32_t d_reg_bits =
1517 EXTRACT_BITS(function_info.encoding, UNWIND_ARM_FRAME_D_REG_COUNT_MASK);
1518 switch (d_reg_bits) {
1519 case 0:
1520 // vpush {d8}
1521 cfa_offset -= 8;
1522 row->SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
1523 break;
1524 case 1:
1525 // vpush {d10}
1526 // vpush {d8}
1527 cfa_offset -= 8;
1528 row->SetRegisterLocationToAtCFAPlusOffset(arm_d10, cfa_offset, true);
1529 cfa_offset -= 8;
1530 row->SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
1531 break;
1532 case 2:
1533 // vpush {d12}
1534 // vpush {d10}
1535 // vpush {d8}
1536 cfa_offset -= 8;
1537 row->SetRegisterLocationToAtCFAPlusOffset(arm_d12, cfa_offset, true);
1538 cfa_offset -= 8;
1539 row->SetRegisterLocationToAtCFAPlusOffset(arm_d10, cfa_offset, true);
1540 cfa_offset -= 8;
1541 row->SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
1542 break;
1543 case 3:
1544 // vpush {d14}
1545 // vpush {d12}
1546 // vpush {d10}
1547 // vpush {d8}
1548 cfa_offset -= 8;
1549 row->SetRegisterLocationToAtCFAPlusOffset(arm_d14, cfa_offset, true);
1550 cfa_offset -= 8;
1551 row->SetRegisterLocationToAtCFAPlusOffset(arm_d12, cfa_offset, true);
1552 cfa_offset -= 8;
1553 row->SetRegisterLocationToAtCFAPlusOffset(arm_d10, cfa_offset, true);
1554 cfa_offset -= 8;
1555 row->SetRegisterLocationToAtCFAPlusOffset(arm_d8, cfa_offset, true);
1556 break;
1557 case 4:
1558 // vpush {d14}
1559 // vpush {d12}
1560 // sp = (sp - 24) & (-16);
1561 // vst {d8, d9, d10}
1562 cfa_offset -= 8;
1563 row->SetRegisterLocationToAtCFAPlusOffset(arm_d14, cfa_offset, true);
1564 cfa_offset -= 8;
1565 row->SetRegisterLocationToAtCFAPlusOffset(arm_d12, cfa_offset, true);
1566
1567 // FIXME we don't have a way to represent reg saves at an specific
1568 // alignment short of
1569 // coming up with some DWARF location description.
1570
1571 break;
1572 case 5:
1573 // vpush {d14}
1574 // sp = (sp - 40) & (-16);
1575 // vst {d8, d9, d10, d11}
1576 // vst {d12}
1577
1578 cfa_offset -= 8;
1579 row->SetRegisterLocationToAtCFAPlusOffset(arm_d14, cfa_offset, true);
1580
1581 // FIXME we don't have a way to represent reg saves at an specific
1582 // alignment short of
1583 // coming up with some DWARF location description.
1584
1585 break;
1586 case 6:
1587 // sp = (sp - 56) & (-16);
1588 // vst {d8, d9, d10, d11}
1589 // vst {d12, d13, d14}
1590
1591 // FIXME we don't have a way to represent reg saves at an specific
1592 // alignment short of
1593 // coming up with some DWARF location description.
1594
1595 break;
1596 case 7:
1597 // sp = (sp - 64) & (-16);
1598 // vst {d8, d9, d10, d11}
1599 // vst {d12, d13, d14, d15}
1600
1601 // FIXME we don't have a way to represent reg saves at an specific
1602 // alignment short of
1603 // coming up with some DWARF location description.
1604
1605 break;
1606 }
1607 }
1608
1609 unwind_plan.AppendRow(row);
1610 return true;
1611 }
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