1//===-- IRMemoryMap.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/Expression/IRMemoryMap.h"
10#include "lldb/Target/MemoryRegionInfo.h"
11#include "lldb/Target/Process.h"
12#include "lldb/Target/Target.h"
13#include "lldb/Utility/DataBufferHeap.h"
14#include "lldb/Utility/DataExtractor.h"
15#include "lldb/Utility/LLDBAssert.h"
16#include "lldb/Utility/LLDBLog.h"
17#include "lldb/Utility/Log.h"
18#include "lldb/Utility/Scalar.h"
19#include "lldb/Utility/Status.h"
20
21using namespace lldb_private;
22
23IRMemoryMap::IRMemoryMap(lldb::TargetSP target_sp) : m_target_wp(target_sp) {
24 if (target_sp)
25 m_process_wp = target_sp->GetProcessSP();
26}
27
28IRMemoryMap::~IRMemoryMap() {
29 lldb::ProcessSP process_sp = m_process_wp.lock();
30
31 if (process_sp) {
32 AllocationMap::iterator iter;
33
34 Status err;
35
36 while ((iter = m_allocations.begin()) != m_allocations.end()) {
37 err.Clear();
38 if (iter->second.m_leak)
39 m_allocations.erase(position: iter);
40 else
41 Free(process_address: iter->first, error&: err);
42 }
43 }
44}
45
46lldb::addr_t IRMemoryMap::FindSpace(size_t size) {
47 // The FindSpace algorithm's job is to find a region of memory that the
48 // underlying process is unlikely to be using.
49 //
50 // The memory returned by this function will never be written to. The only
51 // point is that it should not shadow process memory if possible, so that
52 // expressions processing real values from the process do not use the wrong
53 // data.
54 //
55 // If the process can in fact allocate memory (CanJIT() lets us know this)
56 // then this can be accomplished just be allocating memory in the inferior.
57 // Then no guessing is required.
58
59 lldb::TargetSP target_sp = m_target_wp.lock();
60 lldb::ProcessSP process_sp = m_process_wp.lock();
61
62 const bool process_is_alive = process_sp && process_sp->IsAlive();
63
64 lldb::addr_t ret = LLDB_INVALID_ADDRESS;
65 if (size == 0)
66 return ret;
67
68 if (process_is_alive && process_sp->CanJIT()) {
69 Status alloc_error;
70
71 ret = process_sp->AllocateMemory(size, permissions: lldb::ePermissionsReadable |
72 lldb::ePermissionsWritable,
73 error&: alloc_error);
74
75 if (!alloc_error.Success())
76 return LLDB_INVALID_ADDRESS;
77 else
78 return ret;
79 }
80
81 // At this point we know that we need to hunt.
82 //
83 // First, go to the end of the existing allocations we've made if there are
84 // any allocations. Otherwise start at the beginning of memory.
85
86 if (m_allocations.empty()) {
87 ret = 0x0;
88 } else {
89 auto back = m_allocations.rbegin();
90 lldb::addr_t addr = back->first;
91 size_t alloc_size = back->second.m_size;
92 ret = llvm::alignTo(Value: addr + alloc_size, Align: 4096);
93 }
94
95 uint64_t end_of_memory;
96 switch (GetAddressByteSize()) {
97 case 2:
98 end_of_memory = 0xffffull;
99 break;
100 case 4:
101 end_of_memory = 0xffffffffull;
102 break;
103 case 8:
104 end_of_memory = 0xffffffffffffffffull;
105 break;
106 default:
107 lldbassert(false && "Invalid address size.");
108 return LLDB_INVALID_ADDRESS;
109 }
110
111 // Now, if it's possible to use the GetMemoryRegionInfo API to detect mapped
112 // regions, walk forward through memory until a region is found that has
113 // adequate space for our allocation.
114 if (process_is_alive) {
115 MemoryRegionInfo region_info;
116 Status err = process_sp->GetMemoryRegionInfo(load_addr: ret, range_info&: region_info);
117 if (err.Success()) {
118 while (true) {
119 if (region_info.GetReadable() != MemoryRegionInfo::OptionalBool::eNo ||
120 region_info.GetWritable() != MemoryRegionInfo::OptionalBool::eNo ||
121 region_info.GetExecutable() !=
122 MemoryRegionInfo::OptionalBool::eNo) {
123 if (region_info.GetRange().GetRangeEnd() - 1 >= end_of_memory) {
124 ret = LLDB_INVALID_ADDRESS;
125 break;
126 } else {
127 ret = region_info.GetRange().GetRangeEnd();
128 }
129 } else if (ret + size < region_info.GetRange().GetRangeEnd()) {
130 return ret;
131 } else {
132 // ret stays the same. We just need to walk a bit further.
133 }
134
135 err = process_sp->GetMemoryRegionInfo(
136 load_addr: region_info.GetRange().GetRangeEnd(), range_info&: region_info);
137 if (err.Fail()) {
138 lldbassert(0 && "GetMemoryRegionInfo() succeeded, then failed");
139 ret = LLDB_INVALID_ADDRESS;
140 break;
141 }
142 }
143 }
144 }
145
146 // We've tried our algorithm, and it didn't work. Now we have to reset back
147 // to the end of the allocations we've already reported, or use a 'sensible'
148 // default if this is our first allocation.
149 if (m_allocations.empty()) {
150 uint64_t alloc_address = target_sp->GetExprAllocAddress();
151 if (alloc_address > 0) {
152 if (alloc_address >= end_of_memory) {
153 lldbassert(0 && "The allocation address for expression evaluation must "
154 "be within process address space");
155 return LLDB_INVALID_ADDRESS;
156 }
157 ret = alloc_address;
158 } else {
159 uint32_t address_byte_size = GetAddressByteSize();
160 if (address_byte_size != UINT32_MAX) {
161 switch (address_byte_size) {
162 case 2:
163 ret = 0x8000ull;
164 break;
165 case 4:
166 ret = 0xee000000ull;
167 break;
168 case 8:
169 ret = 0xdead0fff00000000ull;
170 break;
171 default:
172 lldbassert(false && "Invalid address size.");
173 return LLDB_INVALID_ADDRESS;
174 }
175 }
176 }
177 } else {
178 auto back = m_allocations.rbegin();
179 lldb::addr_t addr = back->first;
180 size_t alloc_size = back->second.m_size;
181 uint64_t align = target_sp->GetExprAllocAlign();
182 if (align == 0)
183 align = 4096;
184 ret = llvm::alignTo(Value: addr + alloc_size, Align: align);
185 }
186
187 return ret;
188}
189
190IRMemoryMap::AllocationMap::iterator
191IRMemoryMap::FindAllocation(lldb::addr_t addr, size_t size) {
192 if (addr == LLDB_INVALID_ADDRESS)
193 return m_allocations.end();
194
195 AllocationMap::iterator iter = m_allocations.lower_bound(x: addr);
196
197 if (iter == m_allocations.end() || iter->first > addr) {
198 if (iter == m_allocations.begin())
199 return m_allocations.end();
200 iter--;
201 }
202
203 if (iter->first <= addr && iter->first + iter->second.m_size >= addr + size)
204 return iter;
205
206 return m_allocations.end();
207}
208
209bool IRMemoryMap::IntersectsAllocation(lldb::addr_t addr, size_t size) const {
210 if (addr == LLDB_INVALID_ADDRESS)
211 return false;
212
213 AllocationMap::const_iterator iter = m_allocations.lower_bound(x: addr);
214
215 // Since we only know that the returned interval begins at a location greater
216 // than or equal to where the given interval begins, it's possible that the
217 // given interval intersects either the returned interval or the previous
218 // interval. Thus, we need to check both. Note that we only need to check
219 // these two intervals. Since all intervals are disjoint it is not possible
220 // that an adjacent interval does not intersect, but a non-adjacent interval
221 // does intersect.
222 if (iter != m_allocations.end()) {
223 if (AllocationsIntersect(addr1: addr, size1: size, addr2: iter->second.m_process_start,
224 size2: iter->second.m_size))
225 return true;
226 }
227
228 if (iter != m_allocations.begin()) {
229 --iter;
230 if (AllocationsIntersect(addr1: addr, size1: size, addr2: iter->second.m_process_start,
231 size2: iter->second.m_size))
232 return true;
233 }
234
235 return false;
236}
237
238bool IRMemoryMap::AllocationsIntersect(lldb::addr_t addr1, size_t size1,
239 lldb::addr_t addr2, size_t size2) {
240 // Given two half open intervals [A, B) and [X, Y), the only 6 permutations
241 // that satisfy A<B and X<Y are the following:
242 // A B X Y
243 // A X B Y (intersects)
244 // A X Y B (intersects)
245 // X A B Y (intersects)
246 // X A Y B (intersects)
247 // X Y A B
248 // The first is B <= X, and the last is Y <= A. So the condition is !(B <= X
249 // || Y <= A)), or (X < B && A < Y)
250 return (addr2 < (addr1 + size1)) && (addr1 < (addr2 + size2));
251}
252
253lldb::ByteOrder IRMemoryMap::GetByteOrder() {
254 lldb::ProcessSP process_sp = m_process_wp.lock();
255
256 if (process_sp)
257 return process_sp->GetByteOrder();
258
259 lldb::TargetSP target_sp = m_target_wp.lock();
260
261 if (target_sp)
262 return target_sp->GetArchitecture().GetByteOrder();
263
264 return lldb::eByteOrderInvalid;
265}
266
267uint32_t IRMemoryMap::GetAddressByteSize() {
268 lldb::ProcessSP process_sp = m_process_wp.lock();
269
270 if (process_sp)
271 return process_sp->GetAddressByteSize();
272
273 lldb::TargetSP target_sp = m_target_wp.lock();
274
275 if (target_sp)
276 return target_sp->GetArchitecture().GetAddressByteSize();
277
278 return UINT32_MAX;
279}
280
281ExecutionContextScope *IRMemoryMap::GetBestExecutionContextScope() const {
282 lldb::ProcessSP process_sp = m_process_wp.lock();
283
284 if (process_sp)
285 return process_sp.get();
286
287 lldb::TargetSP target_sp = m_target_wp.lock();
288
289 if (target_sp)
290 return target_sp.get();
291
292 return nullptr;
293}
294
295IRMemoryMap::Allocation::Allocation(lldb::addr_t process_alloc,
296 lldb::addr_t process_start, size_t size,
297 uint32_t permissions, uint8_t alignment,
298 AllocationPolicy policy)
299 : m_process_alloc(process_alloc), m_process_start(process_start),
300 m_size(size), m_policy(policy), m_leak(false), m_permissions(permissions),
301 m_alignment(alignment) {
302 switch (policy) {
303 default:
304 llvm_unreachable("Invalid AllocationPolicy");
305 case eAllocationPolicyHostOnly:
306 case eAllocationPolicyMirror:
307 m_data.SetByteSize(size);
308 break;
309 case eAllocationPolicyProcessOnly:
310 break;
311 }
312}
313
314lldb::addr_t IRMemoryMap::Malloc(size_t size, uint8_t alignment,
315 uint32_t permissions, AllocationPolicy policy,
316 bool zero_memory, Status &error) {
317 lldb_private::Log *log(GetLog(mask: LLDBLog::Expressions));
318 error.Clear();
319
320 lldb::ProcessSP process_sp;
321 lldb::addr_t allocation_address = LLDB_INVALID_ADDRESS;
322 lldb::addr_t aligned_address = LLDB_INVALID_ADDRESS;
323
324 size_t allocation_size;
325
326 if (size == 0) {
327 // FIXME: Malloc(0) should either return an invalid address or assert, in
328 // order to cut down on unnecessary allocations.
329 allocation_size = alignment;
330 } else {
331 // Round up the requested size to an aligned value.
332 allocation_size = llvm::alignTo(Value: size, Align: alignment);
333
334 // The process page cache does not see the requested alignment. We can't
335 // assume its result will be any more than 1-byte aligned. To work around
336 // this, request `alignment - 1` additional bytes.
337 allocation_size += alignment - 1;
338 }
339
340 switch (policy) {
341 default:
342 error.SetErrorToGenericError();
343 error.SetErrorString("Couldn't malloc: invalid allocation policy");
344 return LLDB_INVALID_ADDRESS;
345 case eAllocationPolicyHostOnly:
346 allocation_address = FindSpace(size: allocation_size);
347 if (allocation_address == LLDB_INVALID_ADDRESS) {
348 error.SetErrorToGenericError();
349 error.SetErrorString("Couldn't malloc: address space is full");
350 return LLDB_INVALID_ADDRESS;
351 }
352 break;
353 case eAllocationPolicyMirror:
354 process_sp = m_process_wp.lock();
355 LLDB_LOGF(log,
356 "IRMemoryMap::%s process_sp=0x%" PRIxPTR
357 ", process_sp->CanJIT()=%s, process_sp->IsAlive()=%s",
358 __FUNCTION__, reinterpret_cast<uintptr_t>(process_sp.get()),
359 process_sp && process_sp->CanJIT() ? "true" : "false",
360 process_sp && process_sp->IsAlive() ? "true" : "false");
361 if (process_sp && process_sp->CanJIT() && process_sp->IsAlive()) {
362 if (!zero_memory)
363 allocation_address =
364 process_sp->AllocateMemory(size: allocation_size, permissions, error);
365 else
366 allocation_address =
367 process_sp->CallocateMemory(size: allocation_size, permissions, error);
368
369 if (!error.Success())
370 return LLDB_INVALID_ADDRESS;
371 } else {
372 LLDB_LOGF(log,
373 "IRMemoryMap::%s switching to eAllocationPolicyHostOnly "
374 "due to failed condition (see previous expr log message)",
375 __FUNCTION__);
376 policy = eAllocationPolicyHostOnly;
377 allocation_address = FindSpace(size: allocation_size);
378 if (allocation_address == LLDB_INVALID_ADDRESS) {
379 error.SetErrorToGenericError();
380 error.SetErrorString("Couldn't malloc: address space is full");
381 return LLDB_INVALID_ADDRESS;
382 }
383 }
384 break;
385 case eAllocationPolicyProcessOnly:
386 process_sp = m_process_wp.lock();
387 if (process_sp) {
388 if (process_sp->CanJIT() && process_sp->IsAlive()) {
389 if (!zero_memory)
390 allocation_address =
391 process_sp->AllocateMemory(size: allocation_size, permissions, error);
392 else
393 allocation_address =
394 process_sp->CallocateMemory(size: allocation_size, permissions, error);
395
396 if (!error.Success())
397 return LLDB_INVALID_ADDRESS;
398 } else {
399 error.SetErrorToGenericError();
400 error.SetErrorString(
401 "Couldn't malloc: process doesn't support allocating memory");
402 return LLDB_INVALID_ADDRESS;
403 }
404 } else {
405 error.SetErrorToGenericError();
406 error.SetErrorString("Couldn't malloc: process doesn't exist, and this "
407 "memory must be in the process");
408 return LLDB_INVALID_ADDRESS;
409 }
410 break;
411 }
412
413 lldb::addr_t mask = alignment - 1;
414 aligned_address = (allocation_address + mask) & (~mask);
415
416 m_allocations.emplace(
417 args: std::piecewise_construct, args: std::forward_as_tuple(args&: aligned_address),
418 args: std::forward_as_tuple(args&: allocation_address, args&: aligned_address,
419 args&: allocation_size, args&: permissions, args&: alignment, args&: policy));
420
421 if (zero_memory) {
422 Status write_error;
423 std::vector<uint8_t> zero_buf(size, 0);
424 WriteMemory(process_address: aligned_address, bytes: zero_buf.data(), size, error&: write_error);
425 }
426
427 if (log) {
428 const char *policy_string;
429
430 switch (policy) {
431 default:
432 policy_string = "<invalid policy>";
433 break;
434 case eAllocationPolicyHostOnly:
435 policy_string = "eAllocationPolicyHostOnly";
436 break;
437 case eAllocationPolicyProcessOnly:
438 policy_string = "eAllocationPolicyProcessOnly";
439 break;
440 case eAllocationPolicyMirror:
441 policy_string = "eAllocationPolicyMirror";
442 break;
443 }
444
445 LLDB_LOGF(log,
446 "IRMemoryMap::Malloc (%" PRIu64 ", 0x%" PRIx64 ", 0x%" PRIx64
447 ", %s) -> 0x%" PRIx64,
448 (uint64_t)allocation_size, (uint64_t)alignment,
449 (uint64_t)permissions, policy_string, aligned_address);
450 }
451
452 return aligned_address;
453}
454
455void IRMemoryMap::Leak(lldb::addr_t process_address, Status &error) {
456 error.Clear();
457
458 AllocationMap::iterator iter = m_allocations.find(x: process_address);
459
460 if (iter == m_allocations.end()) {
461 error.SetErrorToGenericError();
462 error.SetErrorString("Couldn't leak: allocation doesn't exist");
463 return;
464 }
465
466 Allocation &allocation = iter->second;
467
468 allocation.m_leak = true;
469}
470
471void IRMemoryMap::Free(lldb::addr_t process_address, Status &error) {
472 error.Clear();
473
474 AllocationMap::iterator iter = m_allocations.find(x: process_address);
475
476 if (iter == m_allocations.end()) {
477 error.SetErrorToGenericError();
478 error.SetErrorString("Couldn't free: allocation doesn't exist");
479 return;
480 }
481
482 Allocation &allocation = iter->second;
483
484 switch (allocation.m_policy) {
485 default:
486 case eAllocationPolicyHostOnly: {
487 lldb::ProcessSP process_sp = m_process_wp.lock();
488 if (process_sp) {
489 if (process_sp->CanJIT() && process_sp->IsAlive())
490 process_sp->DeallocateMemory(
491 ptr: allocation.m_process_alloc); // FindSpace allocated this for real
492 }
493
494 break;
495 }
496 case eAllocationPolicyMirror:
497 case eAllocationPolicyProcessOnly: {
498 lldb::ProcessSP process_sp = m_process_wp.lock();
499 if (process_sp)
500 process_sp->DeallocateMemory(ptr: allocation.m_process_alloc);
501 }
502 }
503
504 if (lldb_private::Log *log = GetLog(mask: LLDBLog::Expressions)) {
505 LLDB_LOGF(log,
506 "IRMemoryMap::Free (0x%" PRIx64 ") freed [0x%" PRIx64
507 "..0x%" PRIx64 ")",
508 (uint64_t)process_address, iter->second.m_process_start,
509 iter->second.m_process_start + iter->second.m_size);
510 }
511
512 m_allocations.erase(position: iter);
513}
514
515bool IRMemoryMap::GetAllocSize(lldb::addr_t address, size_t &size) {
516 AllocationMap::iterator iter = FindAllocation(addr: address, size);
517 if (iter == m_allocations.end())
518 return false;
519
520 Allocation &al = iter->second;
521
522 if (address > (al.m_process_start + al.m_size)) {
523 size = 0;
524 return false;
525 }
526
527 if (address > al.m_process_start) {
528 int dif = address - al.m_process_start;
529 size = al.m_size - dif;
530 return true;
531 }
532
533 size = al.m_size;
534 return true;
535}
536
537void IRMemoryMap::WriteMemory(lldb::addr_t process_address,
538 const uint8_t *bytes, size_t size,
539 Status &error) {
540 error.Clear();
541
542 AllocationMap::iterator iter = FindAllocation(addr: process_address, size);
543
544 if (iter == m_allocations.end()) {
545 lldb::ProcessSP process_sp = m_process_wp.lock();
546
547 if (process_sp) {
548 process_sp->WriteMemory(vm_addr: process_address, buf: bytes, size, error);
549 return;
550 }
551
552 error.SetErrorToGenericError();
553 error.SetErrorString("Couldn't write: no allocation contains the target "
554 "range and the process doesn't exist");
555 return;
556 }
557
558 Allocation &allocation = iter->second;
559
560 uint64_t offset = process_address - allocation.m_process_start;
561
562 lldb::ProcessSP process_sp;
563
564 switch (allocation.m_policy) {
565 default:
566 error.SetErrorToGenericError();
567 error.SetErrorString("Couldn't write: invalid allocation policy");
568 return;
569 case eAllocationPolicyHostOnly:
570 if (!allocation.m_data.GetByteSize()) {
571 error.SetErrorToGenericError();
572 error.SetErrorString("Couldn't write: data buffer is empty");
573 return;
574 }
575 ::memcpy(dest: allocation.m_data.GetBytes() + offset, src: bytes, n: size);
576 break;
577 case eAllocationPolicyMirror:
578 if (!allocation.m_data.GetByteSize()) {
579 error.SetErrorToGenericError();
580 error.SetErrorString("Couldn't write: data buffer is empty");
581 return;
582 }
583 ::memcpy(dest: allocation.m_data.GetBytes() + offset, src: bytes, n: size);
584 process_sp = m_process_wp.lock();
585 if (process_sp) {
586 process_sp->WriteMemory(vm_addr: process_address, buf: bytes, size, error);
587 if (!error.Success())
588 return;
589 }
590 break;
591 case eAllocationPolicyProcessOnly:
592 process_sp = m_process_wp.lock();
593 if (process_sp) {
594 process_sp->WriteMemory(vm_addr: process_address, buf: bytes, size, error);
595 if (!error.Success())
596 return;
597 }
598 break;
599 }
600
601 if (lldb_private::Log *log = GetLog(mask: LLDBLog::Expressions)) {
602 LLDB_LOGF(log,
603 "IRMemoryMap::WriteMemory (0x%" PRIx64 ", 0x%" PRIxPTR
604 ", 0x%" PRId64 ") went to [0x%" PRIx64 "..0x%" PRIx64 ")",
605 (uint64_t)process_address, reinterpret_cast<uintptr_t>(bytes), (uint64_t)size,
606 (uint64_t)allocation.m_process_start,
607 (uint64_t)allocation.m_process_start +
608 (uint64_t)allocation.m_size);
609 }
610}
611
612void IRMemoryMap::WriteScalarToMemory(lldb::addr_t process_address,
613 Scalar &scalar, size_t size,
614 Status &error) {
615 error.Clear();
616
617 if (size == UINT32_MAX)
618 size = scalar.GetByteSize();
619
620 if (size > 0) {
621 uint8_t buf[32];
622 const size_t mem_size =
623 scalar.GetAsMemoryData(dst: buf, dst_len: size, dst_byte_order: GetByteOrder(), error);
624 if (mem_size > 0) {
625 return WriteMemory(process_address, bytes: buf, size: mem_size, error);
626 } else {
627 error.SetErrorToGenericError();
628 error.SetErrorString(
629 "Couldn't write scalar: failed to get scalar as memory data");
630 }
631 } else {
632 error.SetErrorToGenericError();
633 error.SetErrorString("Couldn't write scalar: its size was zero");
634 }
635}
636
637void IRMemoryMap::WritePointerToMemory(lldb::addr_t process_address,
638 lldb::addr_t address, Status &error) {
639 error.Clear();
640
641 Scalar scalar(address);
642
643 WriteScalarToMemory(process_address, scalar, size: GetAddressByteSize(), error);
644}
645
646void IRMemoryMap::ReadMemory(uint8_t *bytes, lldb::addr_t process_address,
647 size_t size, Status &error) {
648 error.Clear();
649
650 AllocationMap::iterator iter = FindAllocation(addr: process_address, size);
651
652 if (iter == m_allocations.end()) {
653 lldb::ProcessSP process_sp = m_process_wp.lock();
654
655 if (process_sp) {
656 process_sp->ReadMemory(vm_addr: process_address, buf: bytes, size, error);
657 return;
658 }
659
660 lldb::TargetSP target_sp = m_target_wp.lock();
661
662 if (target_sp) {
663 Address absolute_address(process_address);
664 target_sp->ReadMemory(addr: absolute_address, dst: bytes, dst_len: size, error, force_live_memory: true);
665 return;
666 }
667
668 error.SetErrorToGenericError();
669 error.SetErrorString("Couldn't read: no allocation contains the target "
670 "range, and neither the process nor the target exist");
671 return;
672 }
673
674 Allocation &allocation = iter->second;
675
676 uint64_t offset = process_address - allocation.m_process_start;
677
678 if (offset > allocation.m_size) {
679 error.SetErrorToGenericError();
680 error.SetErrorString("Couldn't read: data is not in the allocation");
681 return;
682 }
683
684 lldb::ProcessSP process_sp;
685
686 switch (allocation.m_policy) {
687 default:
688 error.SetErrorToGenericError();
689 error.SetErrorString("Couldn't read: invalid allocation policy");
690 return;
691 case eAllocationPolicyHostOnly:
692 if (!allocation.m_data.GetByteSize()) {
693 error.SetErrorToGenericError();
694 error.SetErrorString("Couldn't read: data buffer is empty");
695 return;
696 }
697 if (allocation.m_data.GetByteSize() < offset + size) {
698 error.SetErrorToGenericError();
699 error.SetErrorString("Couldn't read: not enough underlying data");
700 return;
701 }
702
703 ::memcpy(dest: bytes, src: allocation.m_data.GetBytes() + offset, n: size);
704 break;
705 case eAllocationPolicyMirror:
706 process_sp = m_process_wp.lock();
707 if (process_sp) {
708 process_sp->ReadMemory(vm_addr: process_address, buf: bytes, size, error);
709 if (!error.Success())
710 return;
711 } else {
712 if (!allocation.m_data.GetByteSize()) {
713 error.SetErrorToGenericError();
714 error.SetErrorString("Couldn't read: data buffer is empty");
715 return;
716 }
717 ::memcpy(dest: bytes, src: allocation.m_data.GetBytes() + offset, n: size);
718 }
719 break;
720 case eAllocationPolicyProcessOnly:
721 process_sp = m_process_wp.lock();
722 if (process_sp) {
723 process_sp->ReadMemory(vm_addr: process_address, buf: bytes, size, error);
724 if (!error.Success())
725 return;
726 }
727 break;
728 }
729
730 if (lldb_private::Log *log = GetLog(mask: LLDBLog::Expressions)) {
731 LLDB_LOGF(log,
732 "IRMemoryMap::ReadMemory (0x%" PRIx64 ", 0x%" PRIxPTR
733 ", 0x%" PRId64 ") came from [0x%" PRIx64 "..0x%" PRIx64 ")",
734 (uint64_t)process_address, reinterpret_cast<uintptr_t>(bytes), (uint64_t)size,
735 (uint64_t)allocation.m_process_start,
736 (uint64_t)allocation.m_process_start +
737 (uint64_t)allocation.m_size);
738 }
739}
740
741void IRMemoryMap::ReadScalarFromMemory(Scalar &scalar,
742 lldb::addr_t process_address,
743 size_t size, Status &error) {
744 error.Clear();
745
746 if (size > 0) {
747 DataBufferHeap buf(size, 0);
748 ReadMemory(bytes: buf.GetBytes(), process_address, size, error);
749
750 if (!error.Success())
751 return;
752
753 DataExtractor extractor(buf.GetBytes(), buf.GetByteSize(), GetByteOrder(),
754 GetAddressByteSize());
755
756 lldb::offset_t offset = 0;
757
758 switch (size) {
759 default:
760 error.SetErrorToGenericError();
761 error.SetErrorStringWithFormat(
762 "Couldn't read scalar: unsupported size %" PRIu64, (uint64_t)size);
763 return;
764 case 1:
765 scalar = extractor.GetU8(offset_ptr: &offset);
766 break;
767 case 2:
768 scalar = extractor.GetU16(offset_ptr: &offset);
769 break;
770 case 4:
771 scalar = extractor.GetU32(offset_ptr: &offset);
772 break;
773 case 8:
774 scalar = extractor.GetU64(offset_ptr: &offset);
775 break;
776 }
777 } else {
778 error.SetErrorToGenericError();
779 error.SetErrorString("Couldn't read scalar: its size was zero");
780 }
781}
782
783void IRMemoryMap::ReadPointerFromMemory(lldb::addr_t *address,
784 lldb::addr_t process_address,
785 Status &error) {
786 error.Clear();
787
788 Scalar pointer_scalar;
789 ReadScalarFromMemory(scalar&: pointer_scalar, process_address, size: GetAddressByteSize(),
790 error);
791
792 if (!error.Success())
793 return;
794
795 *address = pointer_scalar.ULongLong();
796}
797
798void IRMemoryMap::GetMemoryData(DataExtractor &extractor,
799 lldb::addr_t process_address, size_t size,
800 Status &error) {
801 error.Clear();
802
803 if (size > 0) {
804 AllocationMap::iterator iter = FindAllocation(addr: process_address, size);
805
806 if (iter == m_allocations.end()) {
807 error.SetErrorToGenericError();
808 error.SetErrorStringWithFormat(
809 "Couldn't find an allocation containing [0x%" PRIx64 "..0x%" PRIx64
810 ")",
811 process_address, process_address + size);
812 return;
813 }
814
815 Allocation &allocation = iter->second;
816
817 switch (allocation.m_policy) {
818 default:
819 error.SetErrorToGenericError();
820 error.SetErrorString(
821 "Couldn't get memory data: invalid allocation policy");
822 return;
823 case eAllocationPolicyProcessOnly:
824 error.SetErrorToGenericError();
825 error.SetErrorString(
826 "Couldn't get memory data: memory is only in the target");
827 return;
828 case eAllocationPolicyMirror: {
829 lldb::ProcessSP process_sp = m_process_wp.lock();
830
831 if (!allocation.m_data.GetByteSize()) {
832 error.SetErrorToGenericError();
833 error.SetErrorString("Couldn't get memory data: data buffer is empty");
834 return;
835 }
836 if (process_sp) {
837 process_sp->ReadMemory(vm_addr: allocation.m_process_start,
838 buf: allocation.m_data.GetBytes(),
839 size: allocation.m_data.GetByteSize(), error);
840 if (!error.Success())
841 return;
842 uint64_t offset = process_address - allocation.m_process_start;
843 extractor = DataExtractor(allocation.m_data.GetBytes() + offset, size,
844 GetByteOrder(), GetAddressByteSize());
845 return;
846 }
847 } break;
848 case eAllocationPolicyHostOnly:
849 if (!allocation.m_data.GetByteSize()) {
850 error.SetErrorToGenericError();
851 error.SetErrorString("Couldn't get memory data: data buffer is empty");
852 return;
853 }
854 uint64_t offset = process_address - allocation.m_process_start;
855 extractor = DataExtractor(allocation.m_data.GetBytes() + offset, size,
856 GetByteOrder(), GetAddressByteSize());
857 return;
858 }
859 } else {
860 error.SetErrorToGenericError();
861 error.SetErrorString("Couldn't get memory data: its size was zero");
862 return;
863 }
864}
865

source code of lldb/source/Expression/IRMemoryMap.cpp