File: | build/llvm-toolchain-snapshot-15~++20220315111331+5c4d64eb0de4/lldb/source/Expression/DWARFExpression.cpp |
Warning: | line 2346, column 7 Value stored to 'dwarf4_location_description_kind' is never read |
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1 | //===-- DWARFExpression.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/DWARFExpression.h" |
10 | |
11 | #include <cinttypes> |
12 | |
13 | #include <vector> |
14 | |
15 | #include "lldb/Core/Module.h" |
16 | #include "lldb/Core/Value.h" |
17 | #include "lldb/Core/dwarf.h" |
18 | #include "lldb/Utility/DataEncoder.h" |
19 | #include "lldb/Utility/LLDBLog.h" |
20 | #include "lldb/Utility/Log.h" |
21 | #include "lldb/Utility/RegisterValue.h" |
22 | #include "lldb/Utility/Scalar.h" |
23 | #include "lldb/Utility/StreamString.h" |
24 | #include "lldb/Utility/VMRange.h" |
25 | |
26 | #include "lldb/Host/Host.h" |
27 | #include "lldb/Utility/Endian.h" |
28 | |
29 | #include "lldb/Symbol/Function.h" |
30 | |
31 | #include "lldb/Target/ABI.h" |
32 | #include "lldb/Target/ExecutionContext.h" |
33 | #include "lldb/Target/Process.h" |
34 | #include "lldb/Target/RegisterContext.h" |
35 | #include "lldb/Target/StackFrame.h" |
36 | #include "lldb/Target/StackID.h" |
37 | #include "lldb/Target/Target.h" |
38 | #include "lldb/Target/Thread.h" |
39 | #include "llvm/DebugInfo/DWARF/DWARFDebugLoc.h" |
40 | #include "llvm/DebugInfo/DWARF/DWARFExpression.h" |
41 | |
42 | #include "Plugins/SymbolFile/DWARF/DWARFUnit.h" |
43 | |
44 | using namespace lldb; |
45 | using namespace lldb_private; |
46 | using namespace lldb_private::dwarf; |
47 | |
48 | static lldb::addr_t |
49 | ReadAddressFromDebugAddrSection(const DWARFUnit *dwarf_cu, |
50 | uint32_t index) { |
51 | uint32_t index_size = dwarf_cu->GetAddressByteSize(); |
52 | dw_offset_t addr_base = dwarf_cu->GetAddrBase(); |
53 | lldb::offset_t offset = addr_base + index * index_size; |
54 | const DWARFDataExtractor &data = |
55 | dwarf_cu->GetSymbolFileDWARF().GetDWARFContext().getOrLoadAddrData(); |
56 | if (data.ValidOffsetForDataOfSize(offset, index_size)) |
57 | return data.GetMaxU64_unchecked(&offset, index_size); |
58 | return LLDB_INVALID_ADDRESS(18446744073709551615UL); |
59 | } |
60 | |
61 | // DWARFExpression constructor |
62 | DWARFExpression::DWARFExpression() : m_module_wp(), m_data() {} |
63 | |
64 | DWARFExpression::DWARFExpression(lldb::ModuleSP module_sp, |
65 | const DataExtractor &data, |
66 | const DWARFUnit *dwarf_cu) |
67 | : m_module_wp(), m_data(data), m_dwarf_cu(dwarf_cu) { |
68 | if (module_sp) |
69 | m_module_wp = module_sp; |
70 | } |
71 | |
72 | // Destructor |
73 | DWARFExpression::~DWARFExpression() = default; |
74 | |
75 | bool DWARFExpression::IsValid() const { return m_data.GetByteSize() > 0; } |
76 | |
77 | void DWARFExpression::UpdateValue(uint64_t const_value, |
78 | lldb::offset_t const_value_byte_size, |
79 | uint8_t addr_byte_size) { |
80 | if (!const_value_byte_size) |
81 | return; |
82 | |
83 | m_data.SetData( |
84 | DataBufferSP(new DataBufferHeap(&const_value, const_value_byte_size))); |
85 | m_data.SetByteOrder(endian::InlHostByteOrder()); |
86 | m_data.SetAddressByteSize(addr_byte_size); |
87 | } |
88 | |
89 | void DWARFExpression::DumpLocation(Stream *s, const DataExtractor &data, |
90 | lldb::DescriptionLevel level, |
91 | ABI *abi) const { |
92 | llvm::DWARFExpression(data.GetAsLLVM(), data.GetAddressByteSize()) |
93 | .print(s->AsRawOstream(), llvm::DIDumpOptions(), |
94 | abi ? &abi->GetMCRegisterInfo() : nullptr, nullptr); |
95 | } |
96 | |
97 | void DWARFExpression::SetLocationListAddresses(addr_t cu_file_addr, |
98 | addr_t func_file_addr) { |
99 | m_loclist_addresses = LoclistAddresses{cu_file_addr, func_file_addr}; |
100 | } |
101 | |
102 | int DWARFExpression::GetRegisterKind() { return m_reg_kind; } |
103 | |
104 | void DWARFExpression::SetRegisterKind(RegisterKind reg_kind) { |
105 | m_reg_kind = reg_kind; |
106 | } |
107 | |
108 | bool DWARFExpression::IsLocationList() const { |
109 | return bool(m_loclist_addresses); |
110 | } |
111 | |
112 | namespace { |
113 | /// Implement enough of the DWARFObject interface in order to be able to call |
114 | /// DWARFLocationTable::dumpLocationList. We don't have access to a real |
115 | /// DWARFObject here because DWARFExpression is used in non-DWARF scenarios too. |
116 | class DummyDWARFObject final: public llvm::DWARFObject { |
117 | public: |
118 | DummyDWARFObject(bool IsLittleEndian) : IsLittleEndian(IsLittleEndian) {} |
119 | |
120 | bool isLittleEndian() const override { return IsLittleEndian; } |
121 | |
122 | llvm::Optional<llvm::RelocAddrEntry> find(const llvm::DWARFSection &Sec, |
123 | uint64_t Pos) const override { |
124 | return llvm::None; |
125 | } |
126 | private: |
127 | bool IsLittleEndian; |
128 | }; |
129 | } |
130 | |
131 | void DWARFExpression::GetDescription(Stream *s, lldb::DescriptionLevel level, |
132 | ABI *abi) const { |
133 | if (IsLocationList()) { |
134 | // We have a location list |
135 | lldb::offset_t offset = 0; |
136 | std::unique_ptr<llvm::DWARFLocationTable> loctable_up = |
137 | m_dwarf_cu->GetLocationTable(m_data); |
138 | |
139 | llvm::MCRegisterInfo *MRI = abi ? &abi->GetMCRegisterInfo() : nullptr; |
140 | llvm::DIDumpOptions DumpOpts; |
141 | DumpOpts.RecoverableErrorHandler = [&](llvm::Error E) { |
142 | s->AsRawOstream() << "error: " << toString(std::move(E)); |
143 | }; |
144 | loctable_up->dumpLocationList( |
145 | &offset, s->AsRawOstream(), |
146 | llvm::object::SectionedAddress{m_loclist_addresses->cu_file_addr}, MRI, |
147 | DummyDWARFObject(m_data.GetByteOrder() == eByteOrderLittle), nullptr, |
148 | DumpOpts, s->GetIndentLevel() + 2); |
149 | } else { |
150 | // We have a normal location that contains DW_OP location opcodes |
151 | DumpLocation(s, m_data, level, abi); |
152 | } |
153 | } |
154 | |
155 | static bool ReadRegisterValueAsScalar(RegisterContext *reg_ctx, |
156 | lldb::RegisterKind reg_kind, |
157 | uint32_t reg_num, Status *error_ptr, |
158 | Value &value) { |
159 | if (reg_ctx == nullptr) { |
160 | if (error_ptr) |
161 | error_ptr->SetErrorString("No register context in frame.\n"); |
162 | } else { |
163 | uint32_t native_reg = |
164 | reg_ctx->ConvertRegisterKindToRegisterNumber(reg_kind, reg_num); |
165 | if (native_reg == LLDB_INVALID_REGNUM(4294967295U)) { |
166 | if (error_ptr) |
167 | error_ptr->SetErrorStringWithFormat("Unable to convert register " |
168 | "kind=%u reg_num=%u to a native " |
169 | "register number.\n", |
170 | reg_kind, reg_num); |
171 | } else { |
172 | const RegisterInfo *reg_info = |
173 | reg_ctx->GetRegisterInfoAtIndex(native_reg); |
174 | RegisterValue reg_value; |
175 | if (reg_ctx->ReadRegister(reg_info, reg_value)) { |
176 | if (reg_value.GetScalarValue(value.GetScalar())) { |
177 | value.SetValueType(Value::ValueType::Scalar); |
178 | value.SetContext(Value::ContextType::RegisterInfo, |
179 | const_cast<RegisterInfo *>(reg_info)); |
180 | if (error_ptr) |
181 | error_ptr->Clear(); |
182 | return true; |
183 | } else { |
184 | // If we get this error, then we need to implement a value buffer in |
185 | // the dwarf expression evaluation function... |
186 | if (error_ptr) |
187 | error_ptr->SetErrorStringWithFormat( |
188 | "register %s can't be converted to a scalar value", |
189 | reg_info->name); |
190 | } |
191 | } else { |
192 | if (error_ptr) |
193 | error_ptr->SetErrorStringWithFormat("register %s is not available", |
194 | reg_info->name); |
195 | } |
196 | } |
197 | } |
198 | return false; |
199 | } |
200 | |
201 | /// Return the length in bytes of the set of operands for \p op. No guarantees |
202 | /// are made on the state of \p data after this call. |
203 | static offset_t GetOpcodeDataSize(const DataExtractor &data, |
204 | const lldb::offset_t data_offset, |
205 | const uint8_t op) { |
206 | lldb::offset_t offset = data_offset; |
207 | switch (op) { |
208 | case DW_OP_addr: |
209 | case DW_OP_call_ref: // 0x9a 1 address sized offset of DIE (DWARF3) |
210 | return data.GetAddressByteSize(); |
211 | |
212 | // Opcodes with no arguments |
213 | case DW_OP_deref: // 0x06 |
214 | case DW_OP_dup: // 0x12 |
215 | case DW_OP_drop: // 0x13 |
216 | case DW_OP_over: // 0x14 |
217 | case DW_OP_swap: // 0x16 |
218 | case DW_OP_rot: // 0x17 |
219 | case DW_OP_xderef: // 0x18 |
220 | case DW_OP_abs: // 0x19 |
221 | case DW_OP_and: // 0x1a |
222 | case DW_OP_div: // 0x1b |
223 | case DW_OP_minus: // 0x1c |
224 | case DW_OP_mod: // 0x1d |
225 | case DW_OP_mul: // 0x1e |
226 | case DW_OP_neg: // 0x1f |
227 | case DW_OP_not: // 0x20 |
228 | case DW_OP_or: // 0x21 |
229 | case DW_OP_plus: // 0x22 |
230 | case DW_OP_shl: // 0x24 |
231 | case DW_OP_shr: // 0x25 |
232 | case DW_OP_shra: // 0x26 |
233 | case DW_OP_xor: // 0x27 |
234 | case DW_OP_eq: // 0x29 |
235 | case DW_OP_ge: // 0x2a |
236 | case DW_OP_gt: // 0x2b |
237 | case DW_OP_le: // 0x2c |
238 | case DW_OP_lt: // 0x2d |
239 | case DW_OP_ne: // 0x2e |
240 | case DW_OP_lit0: // 0x30 |
241 | case DW_OP_lit1: // 0x31 |
242 | case DW_OP_lit2: // 0x32 |
243 | case DW_OP_lit3: // 0x33 |
244 | case DW_OP_lit4: // 0x34 |
245 | case DW_OP_lit5: // 0x35 |
246 | case DW_OP_lit6: // 0x36 |
247 | case DW_OP_lit7: // 0x37 |
248 | case DW_OP_lit8: // 0x38 |
249 | case DW_OP_lit9: // 0x39 |
250 | case DW_OP_lit10: // 0x3A |
251 | case DW_OP_lit11: // 0x3B |
252 | case DW_OP_lit12: // 0x3C |
253 | case DW_OP_lit13: // 0x3D |
254 | case DW_OP_lit14: // 0x3E |
255 | case DW_OP_lit15: // 0x3F |
256 | case DW_OP_lit16: // 0x40 |
257 | case DW_OP_lit17: // 0x41 |
258 | case DW_OP_lit18: // 0x42 |
259 | case DW_OP_lit19: // 0x43 |
260 | case DW_OP_lit20: // 0x44 |
261 | case DW_OP_lit21: // 0x45 |
262 | case DW_OP_lit22: // 0x46 |
263 | case DW_OP_lit23: // 0x47 |
264 | case DW_OP_lit24: // 0x48 |
265 | case DW_OP_lit25: // 0x49 |
266 | case DW_OP_lit26: // 0x4A |
267 | case DW_OP_lit27: // 0x4B |
268 | case DW_OP_lit28: // 0x4C |
269 | case DW_OP_lit29: // 0x4D |
270 | case DW_OP_lit30: // 0x4E |
271 | case DW_OP_lit31: // 0x4f |
272 | case DW_OP_reg0: // 0x50 |
273 | case DW_OP_reg1: // 0x51 |
274 | case DW_OP_reg2: // 0x52 |
275 | case DW_OP_reg3: // 0x53 |
276 | case DW_OP_reg4: // 0x54 |
277 | case DW_OP_reg5: // 0x55 |
278 | case DW_OP_reg6: // 0x56 |
279 | case DW_OP_reg7: // 0x57 |
280 | case DW_OP_reg8: // 0x58 |
281 | case DW_OP_reg9: // 0x59 |
282 | case DW_OP_reg10: // 0x5A |
283 | case DW_OP_reg11: // 0x5B |
284 | case DW_OP_reg12: // 0x5C |
285 | case DW_OP_reg13: // 0x5D |
286 | case DW_OP_reg14: // 0x5E |
287 | case DW_OP_reg15: // 0x5F |
288 | case DW_OP_reg16: // 0x60 |
289 | case DW_OP_reg17: // 0x61 |
290 | case DW_OP_reg18: // 0x62 |
291 | case DW_OP_reg19: // 0x63 |
292 | case DW_OP_reg20: // 0x64 |
293 | case DW_OP_reg21: // 0x65 |
294 | case DW_OP_reg22: // 0x66 |
295 | case DW_OP_reg23: // 0x67 |
296 | case DW_OP_reg24: // 0x68 |
297 | case DW_OP_reg25: // 0x69 |
298 | case DW_OP_reg26: // 0x6A |
299 | case DW_OP_reg27: // 0x6B |
300 | case DW_OP_reg28: // 0x6C |
301 | case DW_OP_reg29: // 0x6D |
302 | case DW_OP_reg30: // 0x6E |
303 | case DW_OP_reg31: // 0x6F |
304 | case DW_OP_nop: // 0x96 |
305 | case DW_OP_push_object_address: // 0x97 DWARF3 |
306 | case DW_OP_form_tls_address: // 0x9b DWARF3 |
307 | case DW_OP_call_frame_cfa: // 0x9c DWARF3 |
308 | case DW_OP_stack_value: // 0x9f DWARF4 |
309 | case DW_OP_GNU_push_tls_address: // 0xe0 GNU extension |
310 | return 0; |
311 | |
312 | // Opcodes with a single 1 byte arguments |
313 | case DW_OP_const1u: // 0x08 1 1-byte constant |
314 | case DW_OP_const1s: // 0x09 1 1-byte constant |
315 | case DW_OP_pick: // 0x15 1 1-byte stack index |
316 | case DW_OP_deref_size: // 0x94 1 1-byte size of data retrieved |
317 | case DW_OP_xderef_size: // 0x95 1 1-byte size of data retrieved |
318 | return 1; |
319 | |
320 | // Opcodes with a single 2 byte arguments |
321 | case DW_OP_const2u: // 0x0a 1 2-byte constant |
322 | case DW_OP_const2s: // 0x0b 1 2-byte constant |
323 | case DW_OP_skip: // 0x2f 1 signed 2-byte constant |
324 | case DW_OP_bra: // 0x28 1 signed 2-byte constant |
325 | case DW_OP_call2: // 0x98 1 2-byte offset of DIE (DWARF3) |
326 | return 2; |
327 | |
328 | // Opcodes with a single 4 byte arguments |
329 | case DW_OP_const4u: // 0x0c 1 4-byte constant |
330 | case DW_OP_const4s: // 0x0d 1 4-byte constant |
331 | case DW_OP_call4: // 0x99 1 4-byte offset of DIE (DWARF3) |
332 | return 4; |
333 | |
334 | // Opcodes with a single 8 byte arguments |
335 | case DW_OP_const8u: // 0x0e 1 8-byte constant |
336 | case DW_OP_const8s: // 0x0f 1 8-byte constant |
337 | return 8; |
338 | |
339 | // All opcodes that have a single ULEB (signed or unsigned) argument |
340 | case DW_OP_addrx: // 0xa1 1 ULEB128 index |
341 | case DW_OP_constu: // 0x10 1 ULEB128 constant |
342 | case DW_OP_consts: // 0x11 1 SLEB128 constant |
343 | case DW_OP_plus_uconst: // 0x23 1 ULEB128 addend |
344 | case DW_OP_breg0: // 0x70 1 ULEB128 register |
345 | case DW_OP_breg1: // 0x71 1 ULEB128 register |
346 | case DW_OP_breg2: // 0x72 1 ULEB128 register |
347 | case DW_OP_breg3: // 0x73 1 ULEB128 register |
348 | case DW_OP_breg4: // 0x74 1 ULEB128 register |
349 | case DW_OP_breg5: // 0x75 1 ULEB128 register |
350 | case DW_OP_breg6: // 0x76 1 ULEB128 register |
351 | case DW_OP_breg7: // 0x77 1 ULEB128 register |
352 | case DW_OP_breg8: // 0x78 1 ULEB128 register |
353 | case DW_OP_breg9: // 0x79 1 ULEB128 register |
354 | case DW_OP_breg10: // 0x7a 1 ULEB128 register |
355 | case DW_OP_breg11: // 0x7b 1 ULEB128 register |
356 | case DW_OP_breg12: // 0x7c 1 ULEB128 register |
357 | case DW_OP_breg13: // 0x7d 1 ULEB128 register |
358 | case DW_OP_breg14: // 0x7e 1 ULEB128 register |
359 | case DW_OP_breg15: // 0x7f 1 ULEB128 register |
360 | case DW_OP_breg16: // 0x80 1 ULEB128 register |
361 | case DW_OP_breg17: // 0x81 1 ULEB128 register |
362 | case DW_OP_breg18: // 0x82 1 ULEB128 register |
363 | case DW_OP_breg19: // 0x83 1 ULEB128 register |
364 | case DW_OP_breg20: // 0x84 1 ULEB128 register |
365 | case DW_OP_breg21: // 0x85 1 ULEB128 register |
366 | case DW_OP_breg22: // 0x86 1 ULEB128 register |
367 | case DW_OP_breg23: // 0x87 1 ULEB128 register |
368 | case DW_OP_breg24: // 0x88 1 ULEB128 register |
369 | case DW_OP_breg25: // 0x89 1 ULEB128 register |
370 | case DW_OP_breg26: // 0x8a 1 ULEB128 register |
371 | case DW_OP_breg27: // 0x8b 1 ULEB128 register |
372 | case DW_OP_breg28: // 0x8c 1 ULEB128 register |
373 | case DW_OP_breg29: // 0x8d 1 ULEB128 register |
374 | case DW_OP_breg30: // 0x8e 1 ULEB128 register |
375 | case DW_OP_breg31: // 0x8f 1 ULEB128 register |
376 | case DW_OP_regx: // 0x90 1 ULEB128 register |
377 | case DW_OP_fbreg: // 0x91 1 SLEB128 offset |
378 | case DW_OP_piece: // 0x93 1 ULEB128 size of piece addressed |
379 | case DW_OP_GNU_addr_index: // 0xfb 1 ULEB128 index |
380 | case DW_OP_GNU_const_index: // 0xfc 1 ULEB128 index |
381 | data.Skip_LEB128(&offset); |
382 | return offset - data_offset; |
383 | |
384 | // All opcodes that have a 2 ULEB (signed or unsigned) arguments |
385 | case DW_OP_bregx: // 0x92 2 ULEB128 register followed by SLEB128 offset |
386 | case DW_OP_bit_piece: // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3); |
387 | data.Skip_LEB128(&offset); |
388 | data.Skip_LEB128(&offset); |
389 | return offset - data_offset; |
390 | |
391 | case DW_OP_implicit_value: // 0x9e ULEB128 size followed by block of that size |
392 | // (DWARF4) |
393 | { |
394 | uint64_t block_len = data.Skip_LEB128(&offset); |
395 | offset += block_len; |
396 | return offset - data_offset; |
397 | } |
398 | |
399 | case DW_OP_GNU_entry_value: |
400 | case DW_OP_entry_value: // 0xa3 ULEB128 size + variable-length block |
401 | { |
402 | uint64_t subexpr_len = data.GetULEB128(&offset); |
403 | return (offset - data_offset) + subexpr_len; |
404 | } |
405 | |
406 | default: |
407 | break; |
408 | } |
409 | return LLDB_INVALID_OFFSET(18446744073709551615UL); |
410 | } |
411 | |
412 | lldb::addr_t DWARFExpression::GetLocation_DW_OP_addr(uint32_t op_addr_idx, |
413 | bool &error) const { |
414 | error = false; |
415 | if (IsLocationList()) |
416 | return LLDB_INVALID_ADDRESS(18446744073709551615UL); |
417 | lldb::offset_t offset = 0; |
418 | uint32_t curr_op_addr_idx = 0; |
419 | while (m_data.ValidOffset(offset)) { |
420 | const uint8_t op = m_data.GetU8(&offset); |
421 | |
422 | if (op == DW_OP_addr) { |
423 | const lldb::addr_t op_file_addr = m_data.GetAddress(&offset); |
424 | if (curr_op_addr_idx == op_addr_idx) |
425 | return op_file_addr; |
426 | else |
427 | ++curr_op_addr_idx; |
428 | } else if (op == DW_OP_GNU_addr_index || op == DW_OP_addrx) { |
429 | uint64_t index = m_data.GetULEB128(&offset); |
430 | if (curr_op_addr_idx == op_addr_idx) { |
431 | if (!m_dwarf_cu) { |
432 | error = true; |
433 | break; |
434 | } |
435 | |
436 | return ReadAddressFromDebugAddrSection(m_dwarf_cu, index); |
437 | } else |
438 | ++curr_op_addr_idx; |
439 | } else { |
440 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
441 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) { |
442 | error = true; |
443 | break; |
444 | } |
445 | offset += op_arg_size; |
446 | } |
447 | } |
448 | return LLDB_INVALID_ADDRESS(18446744073709551615UL); |
449 | } |
450 | |
451 | bool DWARFExpression::Update_DW_OP_addr(lldb::addr_t file_addr) { |
452 | if (IsLocationList()) |
453 | return false; |
454 | lldb::offset_t offset = 0; |
455 | while (m_data.ValidOffset(offset)) { |
456 | const uint8_t op = m_data.GetU8(&offset); |
457 | |
458 | if (op == DW_OP_addr) { |
459 | const uint32_t addr_byte_size = m_data.GetAddressByteSize(); |
460 | // We have to make a copy of the data as we don't know if this data is |
461 | // from a read only memory mapped buffer, so we duplicate all of the data |
462 | // first, then modify it, and if all goes well, we then replace the data |
463 | // for this expression |
464 | |
465 | // Make en encoder that contains a copy of the location expression data |
466 | // so we can write the address into the buffer using the correct byte |
467 | // order. |
468 | DataEncoder encoder(m_data.GetDataStart(), m_data.GetByteSize(), |
469 | m_data.GetByteOrder(), addr_byte_size); |
470 | |
471 | // Replace the address in the new buffer |
472 | if (encoder.PutAddress(offset, file_addr) == UINT32_MAX(4294967295U)) |
473 | return false; |
474 | |
475 | // All went well, so now we can reset the data using a shared pointer to |
476 | // the heap data so "m_data" will now correctly manage the heap data. |
477 | m_data.SetData(encoder.GetDataBuffer()); |
478 | return true; |
479 | } else { |
480 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
481 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) |
482 | break; |
483 | offset += op_arg_size; |
484 | } |
485 | } |
486 | return false; |
487 | } |
488 | |
489 | bool DWARFExpression::ContainsThreadLocalStorage() const { |
490 | // We are assuming for now that any thread local variable will not have a |
491 | // location list. This has been true for all thread local variables we have |
492 | // seen so far produced by any compiler. |
493 | if (IsLocationList()) |
494 | return false; |
495 | lldb::offset_t offset = 0; |
496 | while (m_data.ValidOffset(offset)) { |
497 | const uint8_t op = m_data.GetU8(&offset); |
498 | |
499 | if (op == DW_OP_form_tls_address || op == DW_OP_GNU_push_tls_address) |
500 | return true; |
501 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
502 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) |
503 | return false; |
504 | else |
505 | offset += op_arg_size; |
506 | } |
507 | return false; |
508 | } |
509 | bool DWARFExpression::LinkThreadLocalStorage( |
510 | lldb::ModuleSP new_module_sp, |
511 | std::function<lldb::addr_t(lldb::addr_t file_addr)> const |
512 | &link_address_callback) { |
513 | // We are assuming for now that any thread local variable will not have a |
514 | // location list. This has been true for all thread local variables we have |
515 | // seen so far produced by any compiler. |
516 | if (IsLocationList()) |
517 | return false; |
518 | |
519 | const uint32_t addr_byte_size = m_data.GetAddressByteSize(); |
520 | // We have to make a copy of the data as we don't know if this data is from a |
521 | // read only memory mapped buffer, so we duplicate all of the data first, |
522 | // then modify it, and if all goes well, we then replace the data for this |
523 | // expression. |
524 | |
525 | // Make en encoder that contains a copy of the location expression data so we |
526 | // can write the address into the buffer using the correct byte order. |
527 | DataEncoder encoder(m_data.GetDataStart(), m_data.GetByteSize(), |
528 | m_data.GetByteOrder(), addr_byte_size); |
529 | |
530 | lldb::offset_t offset = 0; |
531 | lldb::offset_t const_offset = 0; |
532 | lldb::addr_t const_value = 0; |
533 | size_t const_byte_size = 0; |
534 | while (m_data.ValidOffset(offset)) { |
535 | const uint8_t op = m_data.GetU8(&offset); |
536 | |
537 | bool decoded_data = false; |
538 | switch (op) { |
539 | case DW_OP_const4u: |
540 | // Remember the const offset in case we later have a |
541 | // DW_OP_form_tls_address or DW_OP_GNU_push_tls_address |
542 | const_offset = offset; |
543 | const_value = m_data.GetU32(&offset); |
544 | decoded_data = true; |
545 | const_byte_size = 4; |
546 | break; |
547 | |
548 | case DW_OP_const8u: |
549 | // Remember the const offset in case we later have a |
550 | // DW_OP_form_tls_address or DW_OP_GNU_push_tls_address |
551 | const_offset = offset; |
552 | const_value = m_data.GetU64(&offset); |
553 | decoded_data = true; |
554 | const_byte_size = 8; |
555 | break; |
556 | |
557 | case DW_OP_form_tls_address: |
558 | case DW_OP_GNU_push_tls_address: |
559 | // DW_OP_form_tls_address and DW_OP_GNU_push_tls_address must be preceded |
560 | // by a file address on the stack. We assume that DW_OP_const4u or |
561 | // DW_OP_const8u is used for these values, and we check that the last |
562 | // opcode we got before either of these was DW_OP_const4u or |
563 | // DW_OP_const8u. If so, then we can link the value accodingly. For |
564 | // Darwin, the value in the DW_OP_const4u or DW_OP_const8u is the file |
565 | // address of a structure that contains a function pointer, the pthread |
566 | // key and the offset into the data pointed to by the pthread key. So we |
567 | // must link this address and also set the module of this expression to |
568 | // the new_module_sp so we can resolve the file address correctly |
569 | if (const_byte_size > 0) { |
570 | lldb::addr_t linked_file_addr = link_address_callback(const_value); |
571 | if (linked_file_addr == LLDB_INVALID_ADDRESS(18446744073709551615UL)) |
572 | return false; |
573 | // Replace the address in the new buffer |
574 | if (encoder.PutUnsigned(const_offset, const_byte_size, |
575 | linked_file_addr) == UINT32_MAX(4294967295U)) |
576 | return false; |
577 | } |
578 | break; |
579 | |
580 | default: |
581 | const_offset = 0; |
582 | const_value = 0; |
583 | const_byte_size = 0; |
584 | break; |
585 | } |
586 | |
587 | if (!decoded_data) { |
588 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
589 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) |
590 | return false; |
591 | else |
592 | offset += op_arg_size; |
593 | } |
594 | } |
595 | |
596 | // If we linked the TLS address correctly, update the module so that when the |
597 | // expression is evaluated it can resolve the file address to a load address |
598 | // and read the |
599 | // TLS data |
600 | m_module_wp = new_module_sp; |
601 | m_data.SetData(encoder.GetDataBuffer()); |
602 | return true; |
603 | } |
604 | |
605 | bool DWARFExpression::LocationListContainsAddress(addr_t func_load_addr, |
606 | lldb::addr_t addr) const { |
607 | if (func_load_addr == LLDB_INVALID_ADDRESS(18446744073709551615UL) || addr == LLDB_INVALID_ADDRESS(18446744073709551615UL)) |
608 | return false; |
609 | |
610 | if (!IsLocationList()) |
611 | return false; |
612 | |
613 | return GetLocationExpression(func_load_addr, addr) != llvm::None; |
614 | } |
615 | |
616 | bool DWARFExpression::DumpLocationForAddress(Stream *s, |
617 | lldb::DescriptionLevel level, |
618 | addr_t func_load_addr, |
619 | addr_t address, ABI *abi) { |
620 | if (!IsLocationList()) { |
621 | DumpLocation(s, m_data, level, abi); |
622 | return true; |
623 | } |
624 | if (llvm::Optional<DataExtractor> expr = |
625 | GetLocationExpression(func_load_addr, address)) { |
626 | DumpLocation(s, *expr, level, abi); |
627 | return true; |
628 | } |
629 | return false; |
630 | } |
631 | |
632 | static bool Evaluate_DW_OP_entry_value(std::vector<Value> &stack, |
633 | ExecutionContext *exe_ctx, |
634 | RegisterContext *reg_ctx, |
635 | const DataExtractor &opcodes, |
636 | lldb::offset_t &opcode_offset, |
637 | Status *error_ptr, Log *log) { |
638 | // DW_OP_entry_value(sub-expr) describes the location a variable had upon |
639 | // function entry: this variable location is presumed to be optimized out at |
640 | // the current PC value. The caller of the function may have call site |
641 | // information that describes an alternate location for the variable (e.g. a |
642 | // constant literal, or a spilled stack value) in the parent frame. |
643 | // |
644 | // Example (this is pseudo-code & pseudo-DWARF, but hopefully illustrative): |
645 | // |
646 | // void child(int &sink, int x) { |
647 | // ... |
648 | // /* "x" gets optimized out. */ |
649 | // |
650 | // /* The location of "x" here is: DW_OP_entry_value($reg2). */ |
651 | // ++sink; |
652 | // } |
653 | // |
654 | // void parent() { |
655 | // int sink; |
656 | // |
657 | // /* |
658 | // * The callsite information emitted here is: |
659 | // * |
660 | // * DW_TAG_call_site |
661 | // * DW_AT_return_pc ... (for "child(sink, 123);") |
662 | // * DW_TAG_call_site_parameter (for "sink") |
663 | // * DW_AT_location ($reg1) |
664 | // * DW_AT_call_value ($SP - 8) |
665 | // * DW_TAG_call_site_parameter (for "x") |
666 | // * DW_AT_location ($reg2) |
667 | // * DW_AT_call_value ($literal 123) |
668 | // * |
669 | // * DW_TAG_call_site |
670 | // * DW_AT_return_pc ... (for "child(sink, 456);") |
671 | // * ... |
672 | // */ |
673 | // child(sink, 123); |
674 | // child(sink, 456); |
675 | // } |
676 | // |
677 | // When the program stops at "++sink" within `child`, the debugger determines |
678 | // the call site by analyzing the return address. Once the call site is found, |
679 | // the debugger determines which parameter is referenced by DW_OP_entry_value |
680 | // and evaluates the corresponding location for that parameter in `parent`. |
681 | |
682 | // 1. Find the function which pushed the current frame onto the stack. |
683 | if ((!exe_ctx || !exe_ctx->HasTargetScope()) || !reg_ctx) { |
684 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no exe/reg context")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no exe/reg context") ; } while (0); |
685 | return false; |
686 | } |
687 | |
688 | StackFrame *current_frame = exe_ctx->GetFramePtr(); |
689 | Thread *thread = exe_ctx->GetThreadPtr(); |
690 | if (!current_frame || !thread) { |
691 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no current frame/thread")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no current frame/thread" ); } while (0); |
692 | return false; |
693 | } |
694 | |
695 | Target &target = exe_ctx->GetTargetRef(); |
696 | StackFrameSP parent_frame = nullptr; |
697 | addr_t return_pc = LLDB_INVALID_ADDRESS(18446744073709551615UL); |
698 | uint32_t current_frame_idx = current_frame->GetFrameIndex(); |
699 | uint32_t num_frames = thread->GetStackFrameCount(); |
700 | for (uint32_t parent_frame_idx = current_frame_idx + 1; |
701 | parent_frame_idx < num_frames; ++parent_frame_idx) { |
702 | parent_frame = thread->GetStackFrameAtIndex(parent_frame_idx); |
703 | // Require a valid sequence of frames. |
704 | if (!parent_frame) |
705 | break; |
706 | |
707 | // Record the first valid return address, even if this is an inlined frame, |
708 | // in order to look up the associated call edge in the first non-inlined |
709 | // parent frame. |
710 | if (return_pc == LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
711 | return_pc = parent_frame->GetFrameCodeAddress().GetLoadAddress(&target); |
712 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0) |
713 | "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0) |
714 | return_pc)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0); |
715 | } |
716 | |
717 | // If we've found an inlined frame, skip it (these have no call site |
718 | // parameters). |
719 | if (parent_frame->IsInlined()) |
720 | continue; |
721 | |
722 | // We've found the first non-inlined parent frame. |
723 | break; |
724 | } |
725 | if (!parent_frame || !parent_frame->GetRegisterContext()) { |
726 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no parent frame with reg ctx")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no parent frame with reg ctx" ); } while (0); |
727 | return false; |
728 | } |
729 | |
730 | Function *parent_func = |
731 | parent_frame->GetSymbolContext(eSymbolContextFunction).function; |
732 | if (!parent_func) { |
733 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no parent function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no parent function") ; } while (0); |
734 | return false; |
735 | } |
736 | |
737 | // 2. Find the call edge in the parent function responsible for creating the |
738 | // current activation. |
739 | Function *current_func = |
740 | current_frame->GetSymbolContext(eSymbolContextFunction).function; |
741 | if (!current_func) { |
742 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no current function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no current function" ); } while (0); |
743 | return false; |
744 | } |
745 | |
746 | CallEdge *call_edge = nullptr; |
747 | ModuleList &modlist = target.GetImages(); |
748 | ExecutionContext parent_exe_ctx = *exe_ctx; |
749 | parent_exe_ctx.SetFrameSP(parent_frame); |
750 | if (!parent_frame->IsArtificial()) { |
751 | // If the parent frame is not artificial, the current activation may be |
752 | // produced by an ambiguous tail call. In this case, refuse to proceed. |
753 | call_edge = parent_func->GetCallEdgeForReturnAddress(return_pc, target); |
754 | if (!call_edge) { |
755 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0) |
756 | "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} "do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0) |
757 | "in parent frame {1}",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0) |
758 | return_pc, parent_func->GetName())do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0); |
759 | return false; |
760 | } |
761 | Function *callee_func = call_edge->GetCallee(modlist, parent_exe_ctx); |
762 | if (callee_func != current_func) { |
763 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: ambiguous call sequence, "do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: ambiguous call sequence, " "can't find real parent frame"); } while (0) |
764 | "can't find real parent frame")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: ambiguous call sequence, " "can't find real parent frame"); } while (0); |
765 | return false; |
766 | } |
767 | } else { |
768 | // The StackFrameList solver machinery has deduced that an unambiguous tail |
769 | // call sequence that produced the current activation. The first edge in |
770 | // the parent that points to the current function must be valid. |
771 | for (auto &edge : parent_func->GetTailCallingEdges()) { |
772 | if (edge->GetCallee(modlist, parent_exe_ctx) == current_func) { |
773 | call_edge = edge.get(); |
774 | break; |
775 | } |
776 | } |
777 | } |
778 | if (!call_edge) { |
779 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent "do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent " "to current function"); } while (0) |
780 | "to current function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent " "to current function"); } while (0); |
781 | return false; |
782 | } |
783 | |
784 | // 3. Attempt to locate the DW_OP_entry_value expression in the set of |
785 | // available call site parameters. If found, evaluate the corresponding |
786 | // parameter in the context of the parent frame. |
787 | const uint32_t subexpr_len = opcodes.GetULEB128(&opcode_offset); |
788 | const void *subexpr_data = opcodes.GetData(&opcode_offset, subexpr_len); |
789 | if (!subexpr_data) { |
790 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: subexpr could not be read")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: subexpr could not be read" ); } while (0); |
791 | return false; |
792 | } |
793 | |
794 | const CallSiteParameter *matched_param = nullptr; |
795 | for (const CallSiteParameter ¶m : call_edge->GetCallSiteParameters()) { |
796 | DataExtractor param_subexpr_extractor; |
797 | if (!param.LocationInCallee.GetExpressionData(param_subexpr_extractor)) |
798 | continue; |
799 | lldb::offset_t param_subexpr_offset = 0; |
800 | const void *param_subexpr_data = |
801 | param_subexpr_extractor.GetData(¶m_subexpr_offset, subexpr_len); |
802 | if (!param_subexpr_data || |
803 | param_subexpr_extractor.BytesLeft(param_subexpr_offset) != 0) |
804 | continue; |
805 | |
806 | // At this point, the DW_OP_entry_value sub-expression and the callee-side |
807 | // expression in the call site parameter are known to have the same length. |
808 | // Check whether they are equal. |
809 | // |
810 | // Note that an equality check is sufficient: the contents of the |
811 | // DW_OP_entry_value subexpression are only used to identify the right call |
812 | // site parameter in the parent, and do not require any special handling. |
813 | if (memcmp(subexpr_data, param_subexpr_data, subexpr_len) == 0) { |
814 | matched_param = ¶m; |
815 | break; |
816 | } |
817 | } |
818 | if (!matched_param) { |
819 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no matching call site param found" ); } while (0) |
820 | "Evaluate_DW_OP_entry_value: no matching call site param found")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no matching call site param found" ); } while (0); |
821 | return false; |
822 | } |
823 | |
824 | // TODO: Add support for DW_OP_push_object_address within a DW_OP_entry_value |
825 | // subexpresion whenever llvm does. |
826 | Value result; |
827 | const DWARFExpression ¶m_expr = matched_param->LocationInCaller; |
828 | if (!param_expr.Evaluate(&parent_exe_ctx, |
829 | parent_frame->GetRegisterContext().get(), |
830 | /*loclist_base_load_addr=*/LLDB_INVALID_ADDRESS(18446744073709551615UL), |
831 | /*initial_value_ptr=*/nullptr, |
832 | /*object_address_ptr=*/nullptr, result, error_ptr)) { |
833 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: call site param evaluation failed" ); } while (0) |
834 | "Evaluate_DW_OP_entry_value: call site param evaluation failed")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: call site param evaluation failed" ); } while (0); |
835 | return false; |
836 | } |
837 | |
838 | stack.push_back(result); |
839 | return true; |
840 | } |
841 | |
842 | bool DWARFExpression::Evaluate(ExecutionContextScope *exe_scope, |
843 | lldb::addr_t loclist_base_load_addr, |
844 | const Value *initial_value_ptr, |
845 | const Value *object_address_ptr, Value &result, |
846 | Status *error_ptr) const { |
847 | ExecutionContext exe_ctx(exe_scope); |
848 | return Evaluate(&exe_ctx, nullptr, loclist_base_load_addr, initial_value_ptr, |
849 | object_address_ptr, result, error_ptr); |
850 | } |
851 | |
852 | bool DWARFExpression::Evaluate(ExecutionContext *exe_ctx, |
853 | RegisterContext *reg_ctx, |
854 | lldb::addr_t func_load_addr, |
855 | const Value *initial_value_ptr, |
856 | const Value *object_address_ptr, Value &result, |
857 | Status *error_ptr) const { |
858 | ModuleSP module_sp = m_module_wp.lock(); |
859 | |
860 | if (IsLocationList()) { |
861 | addr_t pc; |
862 | StackFrame *frame = nullptr; |
863 | if (reg_ctx) |
864 | pc = reg_ctx->GetPC(); |
865 | else { |
866 | frame = exe_ctx->GetFramePtr(); |
867 | if (!frame) |
868 | return false; |
869 | RegisterContextSP reg_ctx_sp = frame->GetRegisterContext(); |
870 | if (!reg_ctx_sp) |
871 | return false; |
872 | pc = reg_ctx_sp->GetPC(); |
873 | } |
874 | |
875 | if (func_load_addr != LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
876 | if (pc == LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
877 | if (error_ptr) |
878 | error_ptr->SetErrorString("Invalid PC in frame."); |
879 | return false; |
880 | } |
881 | |
882 | if (llvm::Optional<DataExtractor> expr = |
883 | GetLocationExpression(func_load_addr, pc)) { |
884 | return DWARFExpression::Evaluate( |
885 | exe_ctx, reg_ctx, module_sp, *expr, m_dwarf_cu, m_reg_kind, |
886 | initial_value_ptr, object_address_ptr, result, error_ptr); |
887 | } |
888 | } |
889 | if (error_ptr) |
890 | error_ptr->SetErrorString("variable not available"); |
891 | return false; |
892 | } |
893 | |
894 | // Not a location list, just a single expression. |
895 | return DWARFExpression::Evaluate(exe_ctx, reg_ctx, module_sp, m_data, |
896 | m_dwarf_cu, m_reg_kind, initial_value_ptr, |
897 | object_address_ptr, result, error_ptr); |
898 | } |
899 | |
900 | namespace { |
901 | /// The location description kinds described by the DWARF v5 |
902 | /// specification. Composite locations are handled out-of-band and |
903 | /// thus aren't part of the enum. |
904 | enum LocationDescriptionKind { |
905 | Empty, |
906 | Memory, |
907 | Register, |
908 | Implicit |
909 | /* Composite*/ |
910 | }; |
911 | /// Adjust value's ValueType according to the kind of location description. |
912 | void UpdateValueTypeFromLocationDescription(Log *log, const DWARFUnit *dwarf_cu, |
913 | LocationDescriptionKind kind, |
914 | Value *value = nullptr) { |
915 | // Note that this function is conflating DWARF expressions with |
916 | // DWARF location descriptions. Perhaps it would be better to define |
917 | // a wrapper for DWARFExpresssion::Eval() that deals with DWARF |
918 | // location descriptions (which consist of one or more DWARF |
919 | // expressions). But doing this would mean we'd also need factor the |
920 | // handling of DW_OP_(bit_)piece out of this function. |
921 | if (dwarf_cu && dwarf_cu->GetVersion() >= 4) { |
922 | const char *log_msg = "DWARF location description kind: %s"; |
923 | switch (kind) { |
924 | case Empty: |
925 | LLDB_LOGF(log, log_msg, "Empty")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Empty"); } while (0); |
926 | break; |
927 | case Memory: |
928 | LLDB_LOGF(log, log_msg, "Memory")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Memory"); } while (0); |
929 | if (value->GetValueType() == Value::ValueType::Scalar) |
930 | value->SetValueType(Value::ValueType::LoadAddress); |
931 | break; |
932 | case Register: |
933 | LLDB_LOGF(log, log_msg, "Register")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Register"); } while (0); |
934 | value->SetValueType(Value::ValueType::Scalar); |
935 | break; |
936 | case Implicit: |
937 | LLDB_LOGF(log, log_msg, "Implicit")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Implicit"); } while (0); |
938 | if (value->GetValueType() == Value::ValueType::LoadAddress) |
939 | value->SetValueType(Value::ValueType::Scalar); |
940 | break; |
941 | } |
942 | } |
943 | } |
944 | } // namespace |
945 | |
946 | bool DWARFExpression::Evaluate( |
947 | ExecutionContext *exe_ctx, RegisterContext *reg_ctx, |
948 | lldb::ModuleSP module_sp, const DataExtractor &opcodes, |
949 | const DWARFUnit *dwarf_cu, const lldb::RegisterKind reg_kind, |
950 | const Value *initial_value_ptr, const Value *object_address_ptr, |
951 | Value &result, Status *error_ptr) { |
952 | |
953 | if (opcodes.GetByteSize() == 0) { |
954 | if (error_ptr) |
955 | error_ptr->SetErrorString( |
956 | "no location, value may have been optimized out"); |
957 | return false; |
958 | } |
959 | std::vector<Value> stack; |
960 | |
961 | Process *process = nullptr; |
962 | StackFrame *frame = nullptr; |
963 | |
964 | if (exe_ctx) { |
965 | process = exe_ctx->GetProcessPtr(); |
966 | frame = exe_ctx->GetFramePtr(); |
967 | } |
968 | if (reg_ctx == nullptr && frame) |
969 | reg_ctx = frame->GetRegisterContext().get(); |
970 | |
971 | if (initial_value_ptr) |
972 | stack.push_back(*initial_value_ptr); |
973 | |
974 | lldb::offset_t offset = 0; |
975 | Value tmp; |
976 | uint32_t reg_num; |
977 | |
978 | /// Insertion point for evaluating multi-piece expression. |
979 | uint64_t op_piece_offset = 0; |
980 | Value pieces; // Used for DW_OP_piece |
981 | |
982 | Log *log = GetLog(LLDBLog::Expressions); |
983 | // A generic type is "an integral type that has the size of an address and an |
984 | // unspecified signedness". For now, just use the signedness of the operand. |
985 | // TODO: Implement a real typed stack, and store the genericness of the value |
986 | // there. |
987 | auto to_generic = [&](auto v) { |
988 | bool is_signed = std::is_signed<decltype(v)>::value; |
989 | return Scalar(llvm::APSInt( |
990 | llvm::APInt(8 * opcodes.GetAddressByteSize(), v, is_signed), |
991 | !is_signed)); |
992 | }; |
993 | |
994 | // The default kind is a memory location. This is updated by any |
995 | // operation that changes this, such as DW_OP_stack_value, and reset |
996 | // by composition operations like DW_OP_piece. |
997 | LocationDescriptionKind dwarf4_location_description_kind = Memory; |
998 | |
999 | while (opcodes.ValidOffset(offset)) { |
1000 | const lldb::offset_t op_offset = offset; |
1001 | const uint8_t op = opcodes.GetU8(&offset); |
1002 | |
1003 | if (log && log->GetVerbose()) { |
1004 | size_t count = stack.size(); |
1005 | LLDB_LOGF(log, "Stack before operation has %" PRIu64 " values:",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack before operation has %" "l" "u" " values:", (uint64_t)count); } while (0) |
1006 | (uint64_t)count)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack before operation has %" "l" "u" " values:", (uint64_t)count); } while (0); |
1007 | for (size_t i = 0; i < count; ++i) { |
1008 | StreamString new_value; |
1009 | new_value.Printf("[%" PRIu64"l" "u" "]", (uint64_t)i); |
1010 | stack[i].Dump(&new_value); |
1011 | LLDB_LOGF(log, " %s", new_value.GetData())do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(" %s", new_value.GetData()); } while (0); |
1012 | } |
1013 | LLDB_LOGF(log, "0x%8.8" PRIx64 ": %s", op_offset,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("0x%8.8" "l" "x" ": %s", op_offset, DW_OP_value_to_name (op)); } while (0) |
1014 | DW_OP_value_to_name(op))do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("0x%8.8" "l" "x" ": %s", op_offset, DW_OP_value_to_name (op)); } while (0); |
1015 | } |
1016 | |
1017 | switch (op) { |
1018 | // The DW_OP_addr operation has a single operand that encodes a machine |
1019 | // address and whose size is the size of an address on the target machine. |
1020 | case DW_OP_addr: |
1021 | stack.push_back(Scalar(opcodes.GetAddress(&offset))); |
1022 | stack.back().SetValueType(Value::ValueType::FileAddress); |
1023 | // Convert the file address to a load address, so subsequent |
1024 | // DWARF operators can operate on it. |
1025 | if (frame) |
1026 | stack.back().ConvertToLoadAddress(module_sp.get(), |
1027 | frame->CalculateTarget().get()); |
1028 | break; |
1029 | |
1030 | // The DW_OP_addr_sect_offset4 is used for any location expressions in |
1031 | // shared libraries that have a location like: |
1032 | // DW_OP_addr(0x1000) |
1033 | // If this address resides in a shared library, then this virtual address |
1034 | // won't make sense when it is evaluated in the context of a running |
1035 | // process where shared libraries have been slid. To account for this, this |
1036 | // new address type where we can store the section pointer and a 4 byte |
1037 | // offset. |
1038 | // case DW_OP_addr_sect_offset4: |
1039 | // { |
1040 | // result_type = eResultTypeFileAddress; |
1041 | // lldb::Section *sect = (lldb::Section |
1042 | // *)opcodes.GetMaxU64(&offset, sizeof(void *)); |
1043 | // lldb::addr_t sect_offset = opcodes.GetU32(&offset); |
1044 | // |
1045 | // Address so_addr (sect, sect_offset); |
1046 | // lldb::addr_t load_addr = so_addr.GetLoadAddress(); |
1047 | // if (load_addr != LLDB_INVALID_ADDRESS) |
1048 | // { |
1049 | // // We successfully resolve a file address to a load |
1050 | // // address. |
1051 | // stack.push_back(load_addr); |
1052 | // break; |
1053 | // } |
1054 | // else |
1055 | // { |
1056 | // // We were able |
1057 | // if (error_ptr) |
1058 | // error_ptr->SetErrorStringWithFormat ("Section %s in |
1059 | // %s is not currently loaded.\n", |
1060 | // sect->GetName().AsCString(), |
1061 | // sect->GetModule()->GetFileSpec().GetFilename().AsCString()); |
1062 | // return false; |
1063 | // } |
1064 | // } |
1065 | // break; |
1066 | |
1067 | // OPCODE: DW_OP_deref |
1068 | // OPERANDS: none |
1069 | // DESCRIPTION: Pops the top stack entry and treats it as an address. |
1070 | // The value retrieved from that address is pushed. The size of the data |
1071 | // retrieved from the dereferenced address is the size of an address on the |
1072 | // target machine. |
1073 | case DW_OP_deref: { |
1074 | if (stack.empty()) { |
1075 | if (error_ptr) |
1076 | error_ptr->SetErrorString("Expression stack empty for DW_OP_deref."); |
1077 | return false; |
1078 | } |
1079 | Value::ValueType value_type = stack.back().GetValueType(); |
1080 | switch (value_type) { |
1081 | case Value::ValueType::HostAddress: { |
1082 | void *src = (void *)stack.back().GetScalar().ULongLong(); |
1083 | intptr_t ptr; |
1084 | ::memcpy(&ptr, src, sizeof(void *)); |
1085 | stack.back().GetScalar() = ptr; |
1086 | stack.back().ClearContext(); |
1087 | } break; |
1088 | case Value::ValueType::FileAddress: { |
1089 | auto file_addr = stack.back().GetScalar().ULongLong( |
1090 | LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
1091 | if (!module_sp) { |
1092 | if (error_ptr) |
1093 | error_ptr->SetErrorString( |
1094 | "need module to resolve file address for DW_OP_deref"); |
1095 | return false; |
1096 | } |
1097 | Address so_addr; |
1098 | if (!module_sp->ResolveFileAddress(file_addr, so_addr)) { |
1099 | if (error_ptr) |
1100 | error_ptr->SetErrorString( |
1101 | "failed to resolve file address in module"); |
1102 | return false; |
1103 | } |
1104 | addr_t load_Addr = so_addr.GetLoadAddress(exe_ctx->GetTargetPtr()); |
1105 | if (load_Addr == LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
1106 | if (error_ptr) |
1107 | error_ptr->SetErrorString("failed to resolve load address"); |
1108 | return false; |
1109 | } |
1110 | stack.back().GetScalar() = load_Addr; |
1111 | // Fall through to load address promotion code below. |
1112 | } LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
1113 | case Value::ValueType::Scalar: |
1114 | // Promote Scalar to LoadAddress and fall through. |
1115 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
1116 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
1117 | case Value::ValueType::LoadAddress: |
1118 | if (exe_ctx) { |
1119 | if (process) { |
1120 | lldb::addr_t pointer_addr = |
1121 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
1122 | Status error; |
1123 | lldb::addr_t pointer_value = |
1124 | process->ReadPointerFromMemory(pointer_addr, error); |
1125 | if (pointer_value != LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
1126 | if (ABISP abi_sp = process->GetABI()) |
1127 | pointer_value = abi_sp->FixCodeAddress(pointer_value); |
1128 | stack.back().GetScalar() = pointer_value; |
1129 | stack.back().ClearContext(); |
1130 | } else { |
1131 | if (error_ptr) |
1132 | error_ptr->SetErrorStringWithFormat( |
1133 | "Failed to dereference pointer from 0x%" PRIx64"l" "x" |
1134 | " for DW_OP_deref: %s\n", |
1135 | pointer_addr, error.AsCString()); |
1136 | return false; |
1137 | } |
1138 | } else { |
1139 | if (error_ptr) |
1140 | error_ptr->SetErrorString("NULL process for DW_OP_deref.\n"); |
1141 | return false; |
1142 | } |
1143 | } else { |
1144 | if (error_ptr) |
1145 | error_ptr->SetErrorString( |
1146 | "NULL execution context for DW_OP_deref.\n"); |
1147 | return false; |
1148 | } |
1149 | break; |
1150 | |
1151 | case Value::ValueType::Invalid: |
1152 | if (error_ptr) |
1153 | error_ptr->SetErrorString("Invalid value type for DW_OP_deref.\n"); |
1154 | return false; |
1155 | } |
1156 | |
1157 | } break; |
1158 | |
1159 | // OPCODE: DW_OP_deref_size |
1160 | // OPERANDS: 1 |
1161 | // 1 - uint8_t that specifies the size of the data to dereference. |
1162 | // DESCRIPTION: Behaves like the DW_OP_deref operation: it pops the top |
1163 | // stack entry and treats it as an address. The value retrieved from that |
1164 | // address is pushed. In the DW_OP_deref_size operation, however, the size |
1165 | // in bytes of the data retrieved from the dereferenced address is |
1166 | // specified by the single operand. This operand is a 1-byte unsigned |
1167 | // integral constant whose value may not be larger than the size of an |
1168 | // address on the target machine. The data retrieved is zero extended to |
1169 | // the size of an address on the target machine before being pushed on the |
1170 | // expression stack. |
1171 | case DW_OP_deref_size: { |
1172 | if (stack.empty()) { |
1173 | if (error_ptr) |
1174 | error_ptr->SetErrorString( |
1175 | "Expression stack empty for DW_OP_deref_size."); |
1176 | return false; |
1177 | } |
1178 | uint8_t size = opcodes.GetU8(&offset); |
1179 | Value::ValueType value_type = stack.back().GetValueType(); |
1180 | switch (value_type) { |
1181 | case Value::ValueType::HostAddress: { |
1182 | void *src = (void *)stack.back().GetScalar().ULongLong(); |
1183 | intptr_t ptr; |
1184 | ::memcpy(&ptr, src, sizeof(void *)); |
1185 | // I can't decide whether the size operand should apply to the bytes in |
1186 | // their |
1187 | // lldb-host endianness or the target endianness.. I doubt this'll ever |
1188 | // come up but I'll opt for assuming big endian regardless. |
1189 | switch (size) { |
1190 | case 1: |
1191 | ptr = ptr & 0xff; |
1192 | break; |
1193 | case 2: |
1194 | ptr = ptr & 0xffff; |
1195 | break; |
1196 | case 3: |
1197 | ptr = ptr & 0xffffff; |
1198 | break; |
1199 | case 4: |
1200 | ptr = ptr & 0xffffffff; |
1201 | break; |
1202 | // the casts are added to work around the case where intptr_t is a 32 |
1203 | // bit quantity; |
1204 | // presumably we won't hit the 5..7 cases if (void*) is 32-bits in this |
1205 | // program. |
1206 | case 5: |
1207 | ptr = (intptr_t)ptr & 0xffffffffffULL; |
1208 | break; |
1209 | case 6: |
1210 | ptr = (intptr_t)ptr & 0xffffffffffffULL; |
1211 | break; |
1212 | case 7: |
1213 | ptr = (intptr_t)ptr & 0xffffffffffffffULL; |
1214 | break; |
1215 | default: |
1216 | break; |
1217 | } |
1218 | stack.back().GetScalar() = ptr; |
1219 | stack.back().ClearContext(); |
1220 | } break; |
1221 | case Value::ValueType::Scalar: |
1222 | case Value::ValueType::LoadAddress: |
1223 | if (exe_ctx) { |
1224 | if (process) { |
1225 | lldb::addr_t pointer_addr = |
1226 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
1227 | uint8_t addr_bytes[sizeof(lldb::addr_t)]; |
1228 | Status error; |
1229 | if (process->ReadMemory(pointer_addr, &addr_bytes, size, error) == |
1230 | size) { |
1231 | DataExtractor addr_data(addr_bytes, sizeof(addr_bytes), |
1232 | process->GetByteOrder(), size); |
1233 | lldb::offset_t addr_data_offset = 0; |
1234 | switch (size) { |
1235 | case 1: |
1236 | stack.back().GetScalar() = addr_data.GetU8(&addr_data_offset); |
1237 | break; |
1238 | case 2: |
1239 | stack.back().GetScalar() = addr_data.GetU16(&addr_data_offset); |
1240 | break; |
1241 | case 4: |
1242 | stack.back().GetScalar() = addr_data.GetU32(&addr_data_offset); |
1243 | break; |
1244 | case 8: |
1245 | stack.back().GetScalar() = addr_data.GetU64(&addr_data_offset); |
1246 | break; |
1247 | default: |
1248 | stack.back().GetScalar() = |
1249 | addr_data.GetAddress(&addr_data_offset); |
1250 | } |
1251 | stack.back().ClearContext(); |
1252 | } else { |
1253 | if (error_ptr) |
1254 | error_ptr->SetErrorStringWithFormat( |
1255 | "Failed to dereference pointer from 0x%" PRIx64"l" "x" |
1256 | " for DW_OP_deref: %s\n", |
1257 | pointer_addr, error.AsCString()); |
1258 | return false; |
1259 | } |
1260 | } else { |
1261 | if (error_ptr) |
1262 | error_ptr->SetErrorString("NULL process for DW_OP_deref_size.\n"); |
1263 | return false; |
1264 | } |
1265 | } else { |
1266 | if (error_ptr) |
1267 | error_ptr->SetErrorString( |
1268 | "NULL execution context for DW_OP_deref_size.\n"); |
1269 | return false; |
1270 | } |
1271 | break; |
1272 | |
1273 | case Value::ValueType::FileAddress: |
1274 | case Value::ValueType::Invalid: |
1275 | if (error_ptr) |
1276 | error_ptr->SetErrorString("Invalid value for DW_OP_deref_size.\n"); |
1277 | return false; |
1278 | } |
1279 | |
1280 | } break; |
1281 | |
1282 | // OPCODE: DW_OP_xderef_size |
1283 | // OPERANDS: 1 |
1284 | // 1 - uint8_t that specifies the size of the data to dereference. |
1285 | // DESCRIPTION: Behaves like the DW_OP_xderef operation: the entry at |
1286 | // the top of the stack is treated as an address. The second stack entry is |
1287 | // treated as an "address space identifier" for those architectures that |
1288 | // support multiple address spaces. The top two stack elements are popped, |
1289 | // a data item is retrieved through an implementation-defined address |
1290 | // calculation and pushed as the new stack top. In the DW_OP_xderef_size |
1291 | // operation, however, the size in bytes of the data retrieved from the |
1292 | // dereferenced address is specified by the single operand. This operand is |
1293 | // a 1-byte unsigned integral constant whose value may not be larger than |
1294 | // the size of an address on the target machine. The data retrieved is zero |
1295 | // extended to the size of an address on the target machine before being |
1296 | // pushed on the expression stack. |
1297 | case DW_OP_xderef_size: |
1298 | if (error_ptr) |
1299 | error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef_size."); |
1300 | return false; |
1301 | // OPCODE: DW_OP_xderef |
1302 | // OPERANDS: none |
1303 | // DESCRIPTION: Provides an extended dereference mechanism. The entry at |
1304 | // the top of the stack is treated as an address. The second stack entry is |
1305 | // treated as an "address space identifier" for those architectures that |
1306 | // support multiple address spaces. The top two stack elements are popped, |
1307 | // a data item is retrieved through an implementation-defined address |
1308 | // calculation and pushed as the new stack top. The size of the data |
1309 | // retrieved from the dereferenced address is the size of an address on the |
1310 | // target machine. |
1311 | case DW_OP_xderef: |
1312 | if (error_ptr) |
1313 | error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef."); |
1314 | return false; |
1315 | |
1316 | // All DW_OP_constXXX opcodes have a single operand as noted below: |
1317 | // |
1318 | // Opcode Operand 1 |
1319 | // DW_OP_const1u 1-byte unsigned integer constant |
1320 | // DW_OP_const1s 1-byte signed integer constant |
1321 | // DW_OP_const2u 2-byte unsigned integer constant |
1322 | // DW_OP_const2s 2-byte signed integer constant |
1323 | // DW_OP_const4u 4-byte unsigned integer constant |
1324 | // DW_OP_const4s 4-byte signed integer constant |
1325 | // DW_OP_const8u 8-byte unsigned integer constant |
1326 | // DW_OP_const8s 8-byte signed integer constant |
1327 | // DW_OP_constu unsigned LEB128 integer constant |
1328 | // DW_OP_consts signed LEB128 integer constant |
1329 | case DW_OP_const1u: |
1330 | stack.push_back(to_generic(opcodes.GetU8(&offset))); |
1331 | break; |
1332 | case DW_OP_const1s: |
1333 | stack.push_back(to_generic((int8_t)opcodes.GetU8(&offset))); |
1334 | break; |
1335 | case DW_OP_const2u: |
1336 | stack.push_back(to_generic(opcodes.GetU16(&offset))); |
1337 | break; |
1338 | case DW_OP_const2s: |
1339 | stack.push_back(to_generic((int16_t)opcodes.GetU16(&offset))); |
1340 | break; |
1341 | case DW_OP_const4u: |
1342 | stack.push_back(to_generic(opcodes.GetU32(&offset))); |
1343 | break; |
1344 | case DW_OP_const4s: |
1345 | stack.push_back(to_generic((int32_t)opcodes.GetU32(&offset))); |
1346 | break; |
1347 | case DW_OP_const8u: |
1348 | stack.push_back(to_generic(opcodes.GetU64(&offset))); |
1349 | break; |
1350 | case DW_OP_const8s: |
1351 | stack.push_back(to_generic((int64_t)opcodes.GetU64(&offset))); |
1352 | break; |
1353 | // These should also use to_generic, but we can't do that due to a |
1354 | // producer-side bug in llvm. See llvm.org/pr48087. |
1355 | case DW_OP_constu: |
1356 | stack.push_back(Scalar(opcodes.GetULEB128(&offset))); |
1357 | break; |
1358 | case DW_OP_consts: |
1359 | stack.push_back(Scalar(opcodes.GetSLEB128(&offset))); |
1360 | break; |
1361 | |
1362 | // OPCODE: DW_OP_dup |
1363 | // OPERANDS: none |
1364 | // DESCRIPTION: duplicates the value at the top of the stack |
1365 | case DW_OP_dup: |
1366 | if (stack.empty()) { |
1367 | if (error_ptr) |
1368 | error_ptr->SetErrorString("Expression stack empty for DW_OP_dup."); |
1369 | return false; |
1370 | } else |
1371 | stack.push_back(stack.back()); |
1372 | break; |
1373 | |
1374 | // OPCODE: DW_OP_drop |
1375 | // OPERANDS: none |
1376 | // DESCRIPTION: pops the value at the top of the stack |
1377 | case DW_OP_drop: |
1378 | if (stack.empty()) { |
1379 | if (error_ptr) |
1380 | error_ptr->SetErrorString("Expression stack empty for DW_OP_drop."); |
1381 | return false; |
1382 | } else |
1383 | stack.pop_back(); |
1384 | break; |
1385 | |
1386 | // OPCODE: DW_OP_over |
1387 | // OPERANDS: none |
1388 | // DESCRIPTION: Duplicates the entry currently second in the stack at |
1389 | // the top of the stack. |
1390 | case DW_OP_over: |
1391 | if (stack.size() < 2) { |
1392 | if (error_ptr) |
1393 | error_ptr->SetErrorString( |
1394 | "Expression stack needs at least 2 items for DW_OP_over."); |
1395 | return false; |
1396 | } else |
1397 | stack.push_back(stack[stack.size() - 2]); |
1398 | break; |
1399 | |
1400 | // OPCODE: DW_OP_pick |
1401 | // OPERANDS: uint8_t index into the current stack |
1402 | // DESCRIPTION: The stack entry with the specified index (0 through 255, |
1403 | // inclusive) is pushed on the stack |
1404 | case DW_OP_pick: { |
1405 | uint8_t pick_idx = opcodes.GetU8(&offset); |
1406 | if (pick_idx < stack.size()) |
1407 | stack.push_back(stack[stack.size() - 1 - pick_idx]); |
1408 | else { |
1409 | if (error_ptr) |
1410 | error_ptr->SetErrorStringWithFormat( |
1411 | "Index %u out of range for DW_OP_pick.\n", pick_idx); |
1412 | return false; |
1413 | } |
1414 | } break; |
1415 | |
1416 | // OPCODE: DW_OP_swap |
1417 | // OPERANDS: none |
1418 | // DESCRIPTION: swaps the top two stack entries. The entry at the top |
1419 | // of the stack becomes the second stack entry, and the second entry |
1420 | // becomes the top of the stack |
1421 | case DW_OP_swap: |
1422 | if (stack.size() < 2) { |
1423 | if (error_ptr) |
1424 | error_ptr->SetErrorString( |
1425 | "Expression stack needs at least 2 items for DW_OP_swap."); |
1426 | return false; |
1427 | } else { |
1428 | tmp = stack.back(); |
1429 | stack.back() = stack[stack.size() - 2]; |
1430 | stack[stack.size() - 2] = tmp; |
1431 | } |
1432 | break; |
1433 | |
1434 | // OPCODE: DW_OP_rot |
1435 | // OPERANDS: none |
1436 | // DESCRIPTION: Rotates the first three stack entries. The entry at |
1437 | // the top of the stack becomes the third stack entry, the second entry |
1438 | // becomes the top of the stack, and the third entry becomes the second |
1439 | // entry. |
1440 | case DW_OP_rot: |
1441 | if (stack.size() < 3) { |
1442 | if (error_ptr) |
1443 | error_ptr->SetErrorString( |
1444 | "Expression stack needs at least 3 items for DW_OP_rot."); |
1445 | return false; |
1446 | } else { |
1447 | size_t last_idx = stack.size() - 1; |
1448 | Value old_top = stack[last_idx]; |
1449 | stack[last_idx] = stack[last_idx - 1]; |
1450 | stack[last_idx - 1] = stack[last_idx - 2]; |
1451 | stack[last_idx - 2] = old_top; |
1452 | } |
1453 | break; |
1454 | |
1455 | // OPCODE: DW_OP_abs |
1456 | // OPERANDS: none |
1457 | // DESCRIPTION: pops the top stack entry, interprets it as a signed |
1458 | // value and pushes its absolute value. If the absolute value can not be |
1459 | // represented, the result is undefined. |
1460 | case DW_OP_abs: |
1461 | if (stack.empty()) { |
1462 | if (error_ptr) |
1463 | error_ptr->SetErrorString( |
1464 | "Expression stack needs at least 1 item for DW_OP_abs."); |
1465 | return false; |
1466 | } else if (!stack.back().ResolveValue(exe_ctx).AbsoluteValue()) { |
1467 | if (error_ptr) |
1468 | error_ptr->SetErrorString( |
1469 | "Failed to take the absolute value of the first stack item."); |
1470 | return false; |
1471 | } |
1472 | break; |
1473 | |
1474 | // OPCODE: DW_OP_and |
1475 | // OPERANDS: none |
1476 | // DESCRIPTION: pops the top two stack values, performs a bitwise and |
1477 | // operation on the two, and pushes the result. |
1478 | case DW_OP_and: |
1479 | if (stack.size() < 2) { |
1480 | if (error_ptr) |
1481 | error_ptr->SetErrorString( |
1482 | "Expression stack needs at least 2 items for DW_OP_and."); |
1483 | return false; |
1484 | } else { |
1485 | tmp = stack.back(); |
1486 | stack.pop_back(); |
1487 | stack.back().ResolveValue(exe_ctx) = |
1488 | stack.back().ResolveValue(exe_ctx) & tmp.ResolveValue(exe_ctx); |
1489 | } |
1490 | break; |
1491 | |
1492 | // OPCODE: DW_OP_div |
1493 | // OPERANDS: none |
1494 | // DESCRIPTION: pops the top two stack values, divides the former second |
1495 | // entry by the former top of the stack using signed division, and pushes |
1496 | // the result. |
1497 | case DW_OP_div: |
1498 | if (stack.size() < 2) { |
1499 | if (error_ptr) |
1500 | error_ptr->SetErrorString( |
1501 | "Expression stack needs at least 2 items for DW_OP_div."); |
1502 | return false; |
1503 | } else { |
1504 | tmp = stack.back(); |
1505 | if (tmp.ResolveValue(exe_ctx).IsZero()) { |
1506 | if (error_ptr) |
1507 | error_ptr->SetErrorString("Divide by zero."); |
1508 | return false; |
1509 | } else { |
1510 | stack.pop_back(); |
1511 | stack.back() = |
1512 | stack.back().ResolveValue(exe_ctx) / tmp.ResolveValue(exe_ctx); |
1513 | if (!stack.back().ResolveValue(exe_ctx).IsValid()) { |
1514 | if (error_ptr) |
1515 | error_ptr->SetErrorString("Divide failed."); |
1516 | return false; |
1517 | } |
1518 | } |
1519 | } |
1520 | break; |
1521 | |
1522 | // OPCODE: DW_OP_minus |
1523 | // OPERANDS: none |
1524 | // DESCRIPTION: pops the top two stack values, subtracts the former top |
1525 | // of the stack from the former second entry, and pushes the result. |
1526 | case DW_OP_minus: |
1527 | if (stack.size() < 2) { |
1528 | if (error_ptr) |
1529 | error_ptr->SetErrorString( |
1530 | "Expression stack needs at least 2 items for DW_OP_minus."); |
1531 | return false; |
1532 | } else { |
1533 | tmp = stack.back(); |
1534 | stack.pop_back(); |
1535 | stack.back().ResolveValue(exe_ctx) = |
1536 | stack.back().ResolveValue(exe_ctx) - tmp.ResolveValue(exe_ctx); |
1537 | } |
1538 | break; |
1539 | |
1540 | // OPCODE: DW_OP_mod |
1541 | // OPERANDS: none |
1542 | // DESCRIPTION: pops the top two stack values and pushes the result of |
1543 | // the calculation: former second stack entry modulo the former top of the |
1544 | // stack. |
1545 | case DW_OP_mod: |
1546 | if (stack.size() < 2) { |
1547 | if (error_ptr) |
1548 | error_ptr->SetErrorString( |
1549 | "Expression stack needs at least 2 items for DW_OP_mod."); |
1550 | return false; |
1551 | } else { |
1552 | tmp = stack.back(); |
1553 | stack.pop_back(); |
1554 | stack.back().ResolveValue(exe_ctx) = |
1555 | stack.back().ResolveValue(exe_ctx) % tmp.ResolveValue(exe_ctx); |
1556 | } |
1557 | break; |
1558 | |
1559 | // OPCODE: DW_OP_mul |
1560 | // OPERANDS: none |
1561 | // DESCRIPTION: pops the top two stack entries, multiplies them |
1562 | // together, and pushes the result. |
1563 | case DW_OP_mul: |
1564 | if (stack.size() < 2) { |
1565 | if (error_ptr) |
1566 | error_ptr->SetErrorString( |
1567 | "Expression stack needs at least 2 items for DW_OP_mul."); |
1568 | return false; |
1569 | } else { |
1570 | tmp = stack.back(); |
1571 | stack.pop_back(); |
1572 | stack.back().ResolveValue(exe_ctx) = |
1573 | stack.back().ResolveValue(exe_ctx) * tmp.ResolveValue(exe_ctx); |
1574 | } |
1575 | break; |
1576 | |
1577 | // OPCODE: DW_OP_neg |
1578 | // OPERANDS: none |
1579 | // DESCRIPTION: pops the top stack entry, and pushes its negation. |
1580 | case DW_OP_neg: |
1581 | if (stack.empty()) { |
1582 | if (error_ptr) |
1583 | error_ptr->SetErrorString( |
1584 | "Expression stack needs at least 1 item for DW_OP_neg."); |
1585 | return false; |
1586 | } else { |
1587 | if (!stack.back().ResolveValue(exe_ctx).UnaryNegate()) { |
1588 | if (error_ptr) |
1589 | error_ptr->SetErrorString("Unary negate failed."); |
1590 | return false; |
1591 | } |
1592 | } |
1593 | break; |
1594 | |
1595 | // OPCODE: DW_OP_not |
1596 | // OPERANDS: none |
1597 | // DESCRIPTION: pops the top stack entry, and pushes its bitwise |
1598 | // complement |
1599 | case DW_OP_not: |
1600 | if (stack.empty()) { |
1601 | if (error_ptr) |
1602 | error_ptr->SetErrorString( |
1603 | "Expression stack needs at least 1 item for DW_OP_not."); |
1604 | return false; |
1605 | } else { |
1606 | if (!stack.back().ResolveValue(exe_ctx).OnesComplement()) { |
1607 | if (error_ptr) |
1608 | error_ptr->SetErrorString("Logical NOT failed."); |
1609 | return false; |
1610 | } |
1611 | } |
1612 | break; |
1613 | |
1614 | // OPCODE: DW_OP_or |
1615 | // OPERANDS: none |
1616 | // DESCRIPTION: pops the top two stack entries, performs a bitwise or |
1617 | // operation on the two, and pushes the result. |
1618 | case DW_OP_or: |
1619 | if (stack.size() < 2) { |
1620 | if (error_ptr) |
1621 | error_ptr->SetErrorString( |
1622 | "Expression stack needs at least 2 items for DW_OP_or."); |
1623 | return false; |
1624 | } else { |
1625 | tmp = stack.back(); |
1626 | stack.pop_back(); |
1627 | stack.back().ResolveValue(exe_ctx) = |
1628 | stack.back().ResolveValue(exe_ctx) | tmp.ResolveValue(exe_ctx); |
1629 | } |
1630 | break; |
1631 | |
1632 | // OPCODE: DW_OP_plus |
1633 | // OPERANDS: none |
1634 | // DESCRIPTION: pops the top two stack entries, adds them together, and |
1635 | // pushes the result. |
1636 | case DW_OP_plus: |
1637 | if (stack.size() < 2) { |
1638 | if (error_ptr) |
1639 | error_ptr->SetErrorString( |
1640 | "Expression stack needs at least 2 items for DW_OP_plus."); |
1641 | return false; |
1642 | } else { |
1643 | tmp = stack.back(); |
1644 | stack.pop_back(); |
1645 | stack.back().GetScalar() += tmp.GetScalar(); |
1646 | } |
1647 | break; |
1648 | |
1649 | // OPCODE: DW_OP_plus_uconst |
1650 | // OPERANDS: none |
1651 | // DESCRIPTION: pops the top stack entry, adds it to the unsigned LEB128 |
1652 | // constant operand and pushes the result. |
1653 | case DW_OP_plus_uconst: |
1654 | if (stack.empty()) { |
1655 | if (error_ptr) |
1656 | error_ptr->SetErrorString( |
1657 | "Expression stack needs at least 1 item for DW_OP_plus_uconst."); |
1658 | return false; |
1659 | } else { |
1660 | const uint64_t uconst_value = opcodes.GetULEB128(&offset); |
1661 | // Implicit conversion from a UINT to a Scalar... |
1662 | stack.back().GetScalar() += uconst_value; |
1663 | if (!stack.back().GetScalar().IsValid()) { |
1664 | if (error_ptr) |
1665 | error_ptr->SetErrorString("DW_OP_plus_uconst failed."); |
1666 | return false; |
1667 | } |
1668 | } |
1669 | break; |
1670 | |
1671 | // OPCODE: DW_OP_shl |
1672 | // OPERANDS: none |
1673 | // DESCRIPTION: pops the top two stack entries, shifts the former |
1674 | // second entry left by the number of bits specified by the former top of |
1675 | // the stack, and pushes the result. |
1676 | case DW_OP_shl: |
1677 | if (stack.size() < 2) { |
1678 | if (error_ptr) |
1679 | error_ptr->SetErrorString( |
1680 | "Expression stack needs at least 2 items for DW_OP_shl."); |
1681 | return false; |
1682 | } else { |
1683 | tmp = stack.back(); |
1684 | stack.pop_back(); |
1685 | stack.back().ResolveValue(exe_ctx) <<= tmp.ResolveValue(exe_ctx); |
1686 | } |
1687 | break; |
1688 | |
1689 | // OPCODE: DW_OP_shr |
1690 | // OPERANDS: none |
1691 | // DESCRIPTION: pops the top two stack entries, shifts the former second |
1692 | // entry right logically (filling with zero bits) by the number of bits |
1693 | // specified by the former top of the stack, and pushes the result. |
1694 | case DW_OP_shr: |
1695 | if (stack.size() < 2) { |
1696 | if (error_ptr) |
1697 | error_ptr->SetErrorString( |
1698 | "Expression stack needs at least 2 items for DW_OP_shr."); |
1699 | return false; |
1700 | } else { |
1701 | tmp = stack.back(); |
1702 | stack.pop_back(); |
1703 | if (!stack.back().ResolveValue(exe_ctx).ShiftRightLogical( |
1704 | tmp.ResolveValue(exe_ctx))) { |
1705 | if (error_ptr) |
1706 | error_ptr->SetErrorString("DW_OP_shr failed."); |
1707 | return false; |
1708 | } |
1709 | } |
1710 | break; |
1711 | |
1712 | // OPCODE: DW_OP_shra |
1713 | // OPERANDS: none |
1714 | // DESCRIPTION: pops the top two stack entries, shifts the former second |
1715 | // entry right arithmetically (divide the magnitude by 2, keep the same |
1716 | // sign for the result) by the number of bits specified by the former top |
1717 | // of the stack, and pushes the result. |
1718 | case DW_OP_shra: |
1719 | if (stack.size() < 2) { |
1720 | if (error_ptr) |
1721 | error_ptr->SetErrorString( |
1722 | "Expression stack needs at least 2 items for DW_OP_shra."); |
1723 | return false; |
1724 | } else { |
1725 | tmp = stack.back(); |
1726 | stack.pop_back(); |
1727 | stack.back().ResolveValue(exe_ctx) >>= tmp.ResolveValue(exe_ctx); |
1728 | } |
1729 | break; |
1730 | |
1731 | // OPCODE: DW_OP_xor |
1732 | // OPERANDS: none |
1733 | // DESCRIPTION: pops the top two stack entries, performs the bitwise |
1734 | // exclusive-or operation on the two, and pushes the result. |
1735 | case DW_OP_xor: |
1736 | if (stack.size() < 2) { |
1737 | if (error_ptr) |
1738 | error_ptr->SetErrorString( |
1739 | "Expression stack needs at least 2 items for DW_OP_xor."); |
1740 | return false; |
1741 | } else { |
1742 | tmp = stack.back(); |
1743 | stack.pop_back(); |
1744 | stack.back().ResolveValue(exe_ctx) = |
1745 | stack.back().ResolveValue(exe_ctx) ^ tmp.ResolveValue(exe_ctx); |
1746 | } |
1747 | break; |
1748 | |
1749 | // OPCODE: DW_OP_skip |
1750 | // OPERANDS: int16_t |
1751 | // DESCRIPTION: An unconditional branch. Its single operand is a 2-byte |
1752 | // signed integer constant. The 2-byte constant is the number of bytes of |
1753 | // the DWARF expression to skip forward or backward from the current |
1754 | // operation, beginning after the 2-byte constant. |
1755 | case DW_OP_skip: { |
1756 | int16_t skip_offset = (int16_t)opcodes.GetU16(&offset); |
1757 | lldb::offset_t new_offset = offset + skip_offset; |
1758 | if (opcodes.ValidOffset(new_offset)) |
1759 | offset = new_offset; |
1760 | else { |
1761 | if (error_ptr) |
1762 | error_ptr->SetErrorString("Invalid opcode offset in DW_OP_skip."); |
1763 | return false; |
1764 | } |
1765 | } break; |
1766 | |
1767 | // OPCODE: DW_OP_bra |
1768 | // OPERANDS: int16_t |
1769 | // DESCRIPTION: A conditional branch. Its single operand is a 2-byte |
1770 | // signed integer constant. This operation pops the top of stack. If the |
1771 | // value popped is not the constant 0, the 2-byte constant operand is the |
1772 | // number of bytes of the DWARF expression to skip forward or backward from |
1773 | // the current operation, beginning after the 2-byte constant. |
1774 | case DW_OP_bra: |
1775 | if (stack.empty()) { |
1776 | if (error_ptr) |
1777 | error_ptr->SetErrorString( |
1778 | "Expression stack needs at least 1 item for DW_OP_bra."); |
1779 | return false; |
1780 | } else { |
1781 | tmp = stack.back(); |
1782 | stack.pop_back(); |
1783 | int16_t bra_offset = (int16_t)opcodes.GetU16(&offset); |
1784 | Scalar zero(0); |
1785 | if (tmp.ResolveValue(exe_ctx) != zero) { |
1786 | lldb::offset_t new_offset = offset + bra_offset; |
1787 | if (opcodes.ValidOffset(new_offset)) |
1788 | offset = new_offset; |
1789 | else { |
1790 | if (error_ptr) |
1791 | error_ptr->SetErrorString("Invalid opcode offset in DW_OP_bra."); |
1792 | return false; |
1793 | } |
1794 | } |
1795 | } |
1796 | break; |
1797 | |
1798 | // OPCODE: DW_OP_eq |
1799 | // OPERANDS: none |
1800 | // DESCRIPTION: pops the top two stack values, compares using the |
1801 | // equals (==) operator. |
1802 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1803 | // of the operation is true or the constant value 0 if the result of the |
1804 | // operation is false. |
1805 | case DW_OP_eq: |
1806 | if (stack.size() < 2) { |
1807 | if (error_ptr) |
1808 | error_ptr->SetErrorString( |
1809 | "Expression stack needs at least 2 items for DW_OP_eq."); |
1810 | return false; |
1811 | } else { |
1812 | tmp = stack.back(); |
1813 | stack.pop_back(); |
1814 | stack.back().ResolveValue(exe_ctx) = |
1815 | stack.back().ResolveValue(exe_ctx) == tmp.ResolveValue(exe_ctx); |
1816 | } |
1817 | break; |
1818 | |
1819 | // OPCODE: DW_OP_ge |
1820 | // OPERANDS: none |
1821 | // DESCRIPTION: pops the top two stack values, compares using the |
1822 | // greater than or equal to (>=) operator. |
1823 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1824 | // of the operation is true or the constant value 0 if the result of the |
1825 | // operation is false. |
1826 | case DW_OP_ge: |
1827 | if (stack.size() < 2) { |
1828 | if (error_ptr) |
1829 | error_ptr->SetErrorString( |
1830 | "Expression stack needs at least 2 items for DW_OP_ge."); |
1831 | return false; |
1832 | } else { |
1833 | tmp = stack.back(); |
1834 | stack.pop_back(); |
1835 | stack.back().ResolveValue(exe_ctx) = |
1836 | stack.back().ResolveValue(exe_ctx) >= tmp.ResolveValue(exe_ctx); |
1837 | } |
1838 | break; |
1839 | |
1840 | // OPCODE: DW_OP_gt |
1841 | // OPERANDS: none |
1842 | // DESCRIPTION: pops the top two stack values, compares using the |
1843 | // greater than (>) operator. |
1844 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1845 | // of the operation is true or the constant value 0 if the result of the |
1846 | // operation is false. |
1847 | case DW_OP_gt: |
1848 | if (stack.size() < 2) { |
1849 | if (error_ptr) |
1850 | error_ptr->SetErrorString( |
1851 | "Expression stack needs at least 2 items for DW_OP_gt."); |
1852 | return false; |
1853 | } else { |
1854 | tmp = stack.back(); |
1855 | stack.pop_back(); |
1856 | stack.back().ResolveValue(exe_ctx) = |
1857 | stack.back().ResolveValue(exe_ctx) > tmp.ResolveValue(exe_ctx); |
1858 | } |
1859 | break; |
1860 | |
1861 | // OPCODE: DW_OP_le |
1862 | // OPERANDS: none |
1863 | // DESCRIPTION: pops the top two stack values, compares using the |
1864 | // less than or equal to (<=) operator. |
1865 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1866 | // of the operation is true or the constant value 0 if the result of the |
1867 | // operation is false. |
1868 | case DW_OP_le: |
1869 | if (stack.size() < 2) { |
1870 | if (error_ptr) |
1871 | error_ptr->SetErrorString( |
1872 | "Expression stack needs at least 2 items for DW_OP_le."); |
1873 | return false; |
1874 | } else { |
1875 | tmp = stack.back(); |
1876 | stack.pop_back(); |
1877 | stack.back().ResolveValue(exe_ctx) = |
1878 | stack.back().ResolveValue(exe_ctx) <= tmp.ResolveValue(exe_ctx); |
1879 | } |
1880 | break; |
1881 | |
1882 | // OPCODE: DW_OP_lt |
1883 | // OPERANDS: none |
1884 | // DESCRIPTION: pops the top two stack values, compares using the |
1885 | // less than (<) operator. |
1886 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1887 | // of the operation is true or the constant value 0 if the result of the |
1888 | // operation is false. |
1889 | case DW_OP_lt: |
1890 | if (stack.size() < 2) { |
1891 | if (error_ptr) |
1892 | error_ptr->SetErrorString( |
1893 | "Expression stack needs at least 2 items for DW_OP_lt."); |
1894 | return false; |
1895 | } else { |
1896 | tmp = stack.back(); |
1897 | stack.pop_back(); |
1898 | stack.back().ResolveValue(exe_ctx) = |
1899 | stack.back().ResolveValue(exe_ctx) < tmp.ResolveValue(exe_ctx); |
1900 | } |
1901 | break; |
1902 | |
1903 | // OPCODE: DW_OP_ne |
1904 | // OPERANDS: none |
1905 | // DESCRIPTION: pops the top two stack values, compares using the |
1906 | // not equal (!=) operator. |
1907 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1908 | // of the operation is true or the constant value 0 if the result of the |
1909 | // operation is false. |
1910 | case DW_OP_ne: |
1911 | if (stack.size() < 2) { |
1912 | if (error_ptr) |
1913 | error_ptr->SetErrorString( |
1914 | "Expression stack needs at least 2 items for DW_OP_ne."); |
1915 | return false; |
1916 | } else { |
1917 | tmp = stack.back(); |
1918 | stack.pop_back(); |
1919 | stack.back().ResolveValue(exe_ctx) = |
1920 | stack.back().ResolveValue(exe_ctx) != tmp.ResolveValue(exe_ctx); |
1921 | } |
1922 | break; |
1923 | |
1924 | // OPCODE: DW_OP_litn |
1925 | // OPERANDS: none |
1926 | // DESCRIPTION: encode the unsigned literal values from 0 through 31. |
1927 | // STACK RESULT: push the unsigned literal constant value onto the top |
1928 | // of the stack. |
1929 | case DW_OP_lit0: |
1930 | case DW_OP_lit1: |
1931 | case DW_OP_lit2: |
1932 | case DW_OP_lit3: |
1933 | case DW_OP_lit4: |
1934 | case DW_OP_lit5: |
1935 | case DW_OP_lit6: |
1936 | case DW_OP_lit7: |
1937 | case DW_OP_lit8: |
1938 | case DW_OP_lit9: |
1939 | case DW_OP_lit10: |
1940 | case DW_OP_lit11: |
1941 | case DW_OP_lit12: |
1942 | case DW_OP_lit13: |
1943 | case DW_OP_lit14: |
1944 | case DW_OP_lit15: |
1945 | case DW_OP_lit16: |
1946 | case DW_OP_lit17: |
1947 | case DW_OP_lit18: |
1948 | case DW_OP_lit19: |
1949 | case DW_OP_lit20: |
1950 | case DW_OP_lit21: |
1951 | case DW_OP_lit22: |
1952 | case DW_OP_lit23: |
1953 | case DW_OP_lit24: |
1954 | case DW_OP_lit25: |
1955 | case DW_OP_lit26: |
1956 | case DW_OP_lit27: |
1957 | case DW_OP_lit28: |
1958 | case DW_OP_lit29: |
1959 | case DW_OP_lit30: |
1960 | case DW_OP_lit31: |
1961 | stack.push_back(to_generic(op - DW_OP_lit0)); |
1962 | break; |
1963 | |
1964 | // OPCODE: DW_OP_regN |
1965 | // OPERANDS: none |
1966 | // DESCRIPTION: Push the value in register n on the top of the stack. |
1967 | case DW_OP_reg0: |
1968 | case DW_OP_reg1: |
1969 | case DW_OP_reg2: |
1970 | case DW_OP_reg3: |
1971 | case DW_OP_reg4: |
1972 | case DW_OP_reg5: |
1973 | case DW_OP_reg6: |
1974 | case DW_OP_reg7: |
1975 | case DW_OP_reg8: |
1976 | case DW_OP_reg9: |
1977 | case DW_OP_reg10: |
1978 | case DW_OP_reg11: |
1979 | case DW_OP_reg12: |
1980 | case DW_OP_reg13: |
1981 | case DW_OP_reg14: |
1982 | case DW_OP_reg15: |
1983 | case DW_OP_reg16: |
1984 | case DW_OP_reg17: |
1985 | case DW_OP_reg18: |
1986 | case DW_OP_reg19: |
1987 | case DW_OP_reg20: |
1988 | case DW_OP_reg21: |
1989 | case DW_OP_reg22: |
1990 | case DW_OP_reg23: |
1991 | case DW_OP_reg24: |
1992 | case DW_OP_reg25: |
1993 | case DW_OP_reg26: |
1994 | case DW_OP_reg27: |
1995 | case DW_OP_reg28: |
1996 | case DW_OP_reg29: |
1997 | case DW_OP_reg30: |
1998 | case DW_OP_reg31: { |
1999 | dwarf4_location_description_kind = Register; |
2000 | reg_num = op - DW_OP_reg0; |
2001 | |
2002 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, tmp)) |
2003 | stack.push_back(tmp); |
2004 | else |
2005 | return false; |
2006 | } break; |
2007 | // OPCODE: DW_OP_regx |
2008 | // OPERANDS: |
2009 | // ULEB128 literal operand that encodes the register. |
2010 | // DESCRIPTION: Push the value in register on the top of the stack. |
2011 | case DW_OP_regx: { |
2012 | dwarf4_location_description_kind = Register; |
2013 | reg_num = opcodes.GetULEB128(&offset); |
2014 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, tmp)) |
2015 | stack.push_back(tmp); |
2016 | else |
2017 | return false; |
2018 | } break; |
2019 | |
2020 | // OPCODE: DW_OP_bregN |
2021 | // OPERANDS: |
2022 | // SLEB128 offset from register N |
2023 | // DESCRIPTION: Value is in memory at the address specified by register |
2024 | // N plus an offset. |
2025 | case DW_OP_breg0: |
2026 | case DW_OP_breg1: |
2027 | case DW_OP_breg2: |
2028 | case DW_OP_breg3: |
2029 | case DW_OP_breg4: |
2030 | case DW_OP_breg5: |
2031 | case DW_OP_breg6: |
2032 | case DW_OP_breg7: |
2033 | case DW_OP_breg8: |
2034 | case DW_OP_breg9: |
2035 | case DW_OP_breg10: |
2036 | case DW_OP_breg11: |
2037 | case DW_OP_breg12: |
2038 | case DW_OP_breg13: |
2039 | case DW_OP_breg14: |
2040 | case DW_OP_breg15: |
2041 | case DW_OP_breg16: |
2042 | case DW_OP_breg17: |
2043 | case DW_OP_breg18: |
2044 | case DW_OP_breg19: |
2045 | case DW_OP_breg20: |
2046 | case DW_OP_breg21: |
2047 | case DW_OP_breg22: |
2048 | case DW_OP_breg23: |
2049 | case DW_OP_breg24: |
2050 | case DW_OP_breg25: |
2051 | case DW_OP_breg26: |
2052 | case DW_OP_breg27: |
2053 | case DW_OP_breg28: |
2054 | case DW_OP_breg29: |
2055 | case DW_OP_breg30: |
2056 | case DW_OP_breg31: { |
2057 | reg_num = op - DW_OP_breg0; |
2058 | |
2059 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, |
2060 | tmp)) { |
2061 | int64_t breg_offset = opcodes.GetSLEB128(&offset); |
2062 | tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset; |
2063 | tmp.ClearContext(); |
2064 | stack.push_back(tmp); |
2065 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2066 | } else |
2067 | return false; |
2068 | } break; |
2069 | // OPCODE: DW_OP_bregx |
2070 | // OPERANDS: 2 |
2071 | // ULEB128 literal operand that encodes the register. |
2072 | // SLEB128 offset from register N |
2073 | // DESCRIPTION: Value is in memory at the address specified by register |
2074 | // N plus an offset. |
2075 | case DW_OP_bregx: { |
2076 | reg_num = opcodes.GetULEB128(&offset); |
2077 | |
2078 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, |
2079 | tmp)) { |
2080 | int64_t breg_offset = opcodes.GetSLEB128(&offset); |
2081 | tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset; |
2082 | tmp.ClearContext(); |
2083 | stack.push_back(tmp); |
2084 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2085 | } else |
2086 | return false; |
2087 | } break; |
2088 | |
2089 | case DW_OP_fbreg: |
2090 | if (exe_ctx) { |
2091 | if (frame) { |
2092 | Scalar value; |
2093 | if (frame->GetFrameBaseValue(value, error_ptr)) { |
2094 | int64_t fbreg_offset = opcodes.GetSLEB128(&offset); |
2095 | value += fbreg_offset; |
2096 | stack.push_back(value); |
2097 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2098 | } else |
2099 | return false; |
2100 | } else { |
2101 | if (error_ptr) |
2102 | error_ptr->SetErrorString( |
2103 | "Invalid stack frame in context for DW_OP_fbreg opcode."); |
2104 | return false; |
2105 | } |
2106 | } else { |
2107 | if (error_ptr) |
2108 | error_ptr->SetErrorString( |
2109 | "NULL execution context for DW_OP_fbreg.\n"); |
2110 | return false; |
2111 | } |
2112 | |
2113 | break; |
2114 | |
2115 | // OPCODE: DW_OP_nop |
2116 | // OPERANDS: none |
2117 | // DESCRIPTION: A place holder. It has no effect on the location stack |
2118 | // or any of its values. |
2119 | case DW_OP_nop: |
2120 | break; |
2121 | |
2122 | // OPCODE: DW_OP_piece |
2123 | // OPERANDS: 1 |
2124 | // ULEB128: byte size of the piece |
2125 | // DESCRIPTION: The operand describes the size in bytes of the piece of |
2126 | // the object referenced by the DWARF expression whose result is at the top |
2127 | // of the stack. If the piece is located in a register, but does not occupy |
2128 | // the entire register, the placement of the piece within that register is |
2129 | // defined by the ABI. |
2130 | // |
2131 | // Many compilers store a single variable in sets of registers, or store a |
2132 | // variable partially in memory and partially in registers. DW_OP_piece |
2133 | // provides a way of describing how large a part of a variable a particular |
2134 | // DWARF expression refers to. |
2135 | case DW_OP_piece: { |
2136 | LocationDescriptionKind piece_locdesc = dwarf4_location_description_kind; |
2137 | // Reset for the next piece. |
2138 | dwarf4_location_description_kind = Memory; |
2139 | |
2140 | const uint64_t piece_byte_size = opcodes.GetULEB128(&offset); |
2141 | |
2142 | if (piece_byte_size > 0) { |
2143 | Value curr_piece; |
2144 | |
2145 | if (stack.empty()) { |
2146 | UpdateValueTypeFromLocationDescription( |
2147 | log, dwarf_cu, LocationDescriptionKind::Empty); |
2148 | // In a multi-piece expression, this means that the current piece is |
2149 | // not available. Fill with zeros for now by resizing the data and |
2150 | // appending it |
2151 | curr_piece.ResizeData(piece_byte_size); |
2152 | // Note that "0" is not a correct value for the unknown bits. |
2153 | // It would be better to also return a mask of valid bits together |
2154 | // with the expression result, so the debugger can print missing |
2155 | // members as "<optimized out>" or something. |
2156 | ::memset(curr_piece.GetBuffer().GetBytes(), 0, piece_byte_size); |
2157 | pieces.AppendDataToHostBuffer(curr_piece); |
2158 | } else { |
2159 | Status error; |
2160 | // Extract the current piece into "curr_piece" |
2161 | Value curr_piece_source_value(stack.back()); |
2162 | stack.pop_back(); |
2163 | UpdateValueTypeFromLocationDescription(log, dwarf_cu, piece_locdesc, |
2164 | &curr_piece_source_value); |
2165 | |
2166 | const Value::ValueType curr_piece_source_value_type = |
2167 | curr_piece_source_value.GetValueType(); |
2168 | switch (curr_piece_source_value_type) { |
2169 | case Value::ValueType::Invalid: |
2170 | return false; |
2171 | case Value::ValueType::LoadAddress: |
2172 | if (process) { |
2173 | if (curr_piece.ResizeData(piece_byte_size) == piece_byte_size) { |
2174 | lldb::addr_t load_addr = |
2175 | curr_piece_source_value.GetScalar().ULongLong( |
2176 | LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
2177 | if (process->ReadMemory( |
2178 | load_addr, curr_piece.GetBuffer().GetBytes(), |
2179 | piece_byte_size, error) != piece_byte_size) { |
2180 | if (error_ptr) |
2181 | error_ptr->SetErrorStringWithFormat( |
2182 | "failed to read memory DW_OP_piece(%" PRIu64"l" "u" |
2183 | ") from 0x%" PRIx64"l" "x", |
2184 | piece_byte_size, load_addr); |
2185 | return false; |
2186 | } |
2187 | } else { |
2188 | if (error_ptr) |
2189 | error_ptr->SetErrorStringWithFormat( |
2190 | "failed to resize the piece memory buffer for " |
2191 | "DW_OP_piece(%" PRIu64"l" "u" ")", |
2192 | piece_byte_size); |
2193 | return false; |
2194 | } |
2195 | } |
2196 | break; |
2197 | |
2198 | case Value::ValueType::FileAddress: |
2199 | case Value::ValueType::HostAddress: |
2200 | if (error_ptr) { |
2201 | lldb::addr_t addr = curr_piece_source_value.GetScalar().ULongLong( |
2202 | LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
2203 | error_ptr->SetErrorStringWithFormat( |
2204 | "failed to read memory DW_OP_piece(%" PRIu64"l" "u" |
2205 | ") from %s address 0x%" PRIx64"l" "x", |
2206 | piece_byte_size, curr_piece_source_value.GetValueType() == |
2207 | Value::ValueType::FileAddress |
2208 | ? "file" |
2209 | : "host", |
2210 | addr); |
2211 | } |
2212 | return false; |
2213 | |
2214 | case Value::ValueType::Scalar: { |
2215 | uint32_t bit_size = piece_byte_size * 8; |
2216 | uint32_t bit_offset = 0; |
2217 | Scalar &scalar = curr_piece_source_value.GetScalar(); |
2218 | if (!scalar.ExtractBitfield( |
2219 | bit_size, bit_offset)) { |
2220 | if (error_ptr) |
2221 | error_ptr->SetErrorStringWithFormat( |
2222 | "unable to extract %" PRIu64"l" "u" " bytes from a %" PRIu64"l" "u" |
2223 | " byte scalar value.", |
2224 | piece_byte_size, |
2225 | (uint64_t)curr_piece_source_value.GetScalar() |
2226 | .GetByteSize()); |
2227 | return false; |
2228 | } |
2229 | // Create curr_piece with bit_size. By default Scalar |
2230 | // grows to the nearest host integer type. |
2231 | llvm::APInt fail_value(1, 0, false); |
2232 | llvm::APInt ap_int = scalar.UInt128(fail_value); |
2233 | assert(ap_int.getBitWidth() >= bit_size)(static_cast <bool> (ap_int.getBitWidth() >= bit_size ) ? void (0) : __assert_fail ("ap_int.getBitWidth() >= bit_size" , "lldb/source/Expression/DWARFExpression.cpp", 2233, __extension__ __PRETTY_FUNCTION__)); |
2234 | llvm::ArrayRef<uint64_t> buf{ap_int.getRawData(), |
2235 | ap_int.getNumWords()}; |
2236 | curr_piece.GetScalar() = Scalar(llvm::APInt(bit_size, buf)); |
2237 | } break; |
2238 | } |
2239 | |
2240 | // Check if this is the first piece? |
2241 | if (op_piece_offset == 0) { |
2242 | // This is the first piece, we should push it back onto the stack |
2243 | // so subsequent pieces will be able to access this piece and add |
2244 | // to it. |
2245 | if (pieces.AppendDataToHostBuffer(curr_piece) == 0) { |
2246 | if (error_ptr) |
2247 | error_ptr->SetErrorString("failed to append piece data"); |
2248 | return false; |
2249 | } |
2250 | } else { |
2251 | // If this is the second or later piece there should be a value on |
2252 | // the stack. |
2253 | if (pieces.GetBuffer().GetByteSize() != op_piece_offset) { |
2254 | if (error_ptr) |
2255 | error_ptr->SetErrorStringWithFormat( |
2256 | "DW_OP_piece for offset %" PRIu64"l" "u" |
2257 | " but top of stack is of size %" PRIu64"l" "u", |
2258 | op_piece_offset, pieces.GetBuffer().GetByteSize()); |
2259 | return false; |
2260 | } |
2261 | |
2262 | if (pieces.AppendDataToHostBuffer(curr_piece) == 0) { |
2263 | if (error_ptr) |
2264 | error_ptr->SetErrorString("failed to append piece data"); |
2265 | return false; |
2266 | } |
2267 | } |
2268 | } |
2269 | op_piece_offset += piece_byte_size; |
2270 | } |
2271 | } break; |
2272 | |
2273 | case DW_OP_bit_piece: // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3); |
2274 | if (stack.size() < 1) { |
2275 | UpdateValueTypeFromLocationDescription(log, dwarf_cu, |
2276 | LocationDescriptionKind::Empty); |
2277 | // Reset for the next piece. |
2278 | dwarf4_location_description_kind = Memory; |
2279 | if (error_ptr) |
2280 | error_ptr->SetErrorString( |
2281 | "Expression stack needs at least 1 item for DW_OP_bit_piece."); |
2282 | return false; |
2283 | } else { |
2284 | UpdateValueTypeFromLocationDescription( |
2285 | log, dwarf_cu, dwarf4_location_description_kind, &stack.back()); |
2286 | // Reset for the next piece. |
2287 | dwarf4_location_description_kind = Memory; |
2288 | const uint64_t piece_bit_size = opcodes.GetULEB128(&offset); |
2289 | const uint64_t piece_bit_offset = opcodes.GetULEB128(&offset); |
2290 | switch (stack.back().GetValueType()) { |
2291 | case Value::ValueType::Invalid: |
2292 | return false; |
2293 | case Value::ValueType::Scalar: { |
2294 | if (!stack.back().GetScalar().ExtractBitfield(piece_bit_size, |
2295 | piece_bit_offset)) { |
2296 | if (error_ptr) |
2297 | error_ptr->SetErrorStringWithFormat( |
2298 | "unable to extract %" PRIu64"l" "u" " bit value with %" PRIu64"l" "u" |
2299 | " bit offset from a %" PRIu64"l" "u" " bit scalar value.", |
2300 | piece_bit_size, piece_bit_offset, |
2301 | (uint64_t)(stack.back().GetScalar().GetByteSize() * 8)); |
2302 | return false; |
2303 | } |
2304 | } break; |
2305 | |
2306 | case Value::ValueType::FileAddress: |
2307 | case Value::ValueType::LoadAddress: |
2308 | case Value::ValueType::HostAddress: |
2309 | if (error_ptr) { |
2310 | error_ptr->SetErrorStringWithFormat( |
2311 | "unable to extract DW_OP_bit_piece(bit_size = %" PRIu64"l" "u" |
2312 | ", bit_offset = %" PRIu64"l" "u" ") from an address value.", |
2313 | piece_bit_size, piece_bit_offset); |
2314 | } |
2315 | return false; |
2316 | } |
2317 | } |
2318 | break; |
2319 | |
2320 | // OPCODE: DW_OP_implicit_value |
2321 | // OPERANDS: 2 |
2322 | // ULEB128 size of the value block in bytes |
2323 | // uint8_t* block bytes encoding value in target's memory |
2324 | // representation |
2325 | // DESCRIPTION: Value is immediately stored in block in the debug info with |
2326 | // the memory representation of the target. |
2327 | case DW_OP_implicit_value: { |
2328 | dwarf4_location_description_kind = Implicit; |
2329 | |
2330 | const uint32_t len = opcodes.GetULEB128(&offset); |
2331 | const void *data = opcodes.GetData(&offset, len); |
2332 | |
2333 | if (!data) { |
2334 | LLDB_LOG(log, "Evaluate_DW_OP_implicit_value: could not be read data")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_implicit_value: could not be read data" ); } while (0); |
2335 | LLDB_ERRORF(error_ptr, "Could not evaluate %s.",do { if (error_ptr) { (error_ptr)->SetErrorStringWithFormat (("Could not evaluate %s."), DW_OP_value_to_name(op)); } } while (0); |
2336 | DW_OP_value_to_name(op))do { if (error_ptr) { (error_ptr)->SetErrorStringWithFormat (("Could not evaluate %s."), DW_OP_value_to_name(op)); } } while (0);; |
2337 | return false; |
2338 | } |
2339 | |
2340 | Value result(data, len); |
2341 | stack.push_back(result); |
2342 | break; |
2343 | } |
2344 | |
2345 | case DW_OP_implicit_pointer: { |
2346 | dwarf4_location_description_kind = Implicit; |
Value stored to 'dwarf4_location_description_kind' is never read | |
2347 | LLDB_ERRORF(error_ptr, "Could not evaluate %s.", DW_OP_value_to_name(op))do { if (error_ptr) { (error_ptr)->SetErrorStringWithFormat (("Could not evaluate %s."), DW_OP_value_to_name(op)); } } while (0);; |
2348 | return false; |
2349 | } |
2350 | |
2351 | // OPCODE: DW_OP_push_object_address |
2352 | // OPERANDS: none |
2353 | // DESCRIPTION: Pushes the address of the object currently being |
2354 | // evaluated as part of evaluation of a user presented expression. This |
2355 | // object may correspond to an independent variable described by its own |
2356 | // DIE or it may be a component of an array, structure, or class whose |
2357 | // address has been dynamically determined by an earlier step during user |
2358 | // expression evaluation. |
2359 | case DW_OP_push_object_address: |
2360 | if (object_address_ptr) |
2361 | stack.push_back(*object_address_ptr); |
2362 | else { |
2363 | if (error_ptr) |
2364 | error_ptr->SetErrorString("DW_OP_push_object_address used without " |
2365 | "specifying an object address"); |
2366 | return false; |
2367 | } |
2368 | break; |
2369 | |
2370 | // OPCODE: DW_OP_call2 |
2371 | // OPERANDS: |
2372 | // uint16_t compile unit relative offset of a DIE |
2373 | // DESCRIPTION: Performs subroutine calls during evaluation |
2374 | // of a DWARF expression. The operand is the 2-byte unsigned offset of a |
2375 | // debugging information entry in the current compilation unit. |
2376 | // |
2377 | // Operand interpretation is exactly like that for DW_FORM_ref2. |
2378 | // |
2379 | // This operation transfers control of DWARF expression evaluation to the |
2380 | // DW_AT_location attribute of the referenced DIE. If there is no such |
2381 | // attribute, then there is no effect. Execution of the DWARF expression of |
2382 | // a DW_AT_location attribute may add to and/or remove from values on the |
2383 | // stack. Execution returns to the point following the call when the end of |
2384 | // the attribute is reached. Values on the stack at the time of the call |
2385 | // may be used as parameters by the called expression and values left on |
2386 | // the stack by the called expression may be used as return values by prior |
2387 | // agreement between the calling and called expressions. |
2388 | case DW_OP_call2: |
2389 | if (error_ptr) |
2390 | error_ptr->SetErrorString("Unimplemented opcode DW_OP_call2."); |
2391 | return false; |
2392 | // OPCODE: DW_OP_call4 |
2393 | // OPERANDS: 1 |
2394 | // uint32_t compile unit relative offset of a DIE |
2395 | // DESCRIPTION: Performs a subroutine call during evaluation of a DWARF |
2396 | // expression. For DW_OP_call4, the operand is a 4-byte unsigned offset of |
2397 | // a debugging information entry in the current compilation unit. |
2398 | // |
2399 | // Operand interpretation DW_OP_call4 is exactly like that for |
2400 | // DW_FORM_ref4. |
2401 | // |
2402 | // This operation transfers control of DWARF expression evaluation to the |
2403 | // DW_AT_location attribute of the referenced DIE. If there is no such |
2404 | // attribute, then there is no effect. Execution of the DWARF expression of |
2405 | // a DW_AT_location attribute may add to and/or remove from values on the |
2406 | // stack. Execution returns to the point following the call when the end of |
2407 | // the attribute is reached. Values on the stack at the time of the call |
2408 | // may be used as parameters by the called expression and values left on |
2409 | // the stack by the called expression may be used as return values by prior |
2410 | // agreement between the calling and called expressions. |
2411 | case DW_OP_call4: |
2412 | if (error_ptr) |
2413 | error_ptr->SetErrorString("Unimplemented opcode DW_OP_call4."); |
2414 | return false; |
2415 | |
2416 | // OPCODE: DW_OP_stack_value |
2417 | // OPERANDS: None |
2418 | // DESCRIPTION: Specifies that the object does not exist in memory but |
2419 | // rather is a constant value. The value from the top of the stack is the |
2420 | // value to be used. This is the actual object value and not the location. |
2421 | case DW_OP_stack_value: |
2422 | dwarf4_location_description_kind = Implicit; |
2423 | if (stack.empty()) { |
2424 | if (error_ptr) |
2425 | error_ptr->SetErrorString( |
2426 | "Expression stack needs at least 1 item for DW_OP_stack_value."); |
2427 | return false; |
2428 | } |
2429 | stack.back().SetValueType(Value::ValueType::Scalar); |
2430 | break; |
2431 | |
2432 | // OPCODE: DW_OP_convert |
2433 | // OPERANDS: 1 |
2434 | // A ULEB128 that is either a DIE offset of a |
2435 | // DW_TAG_base_type or 0 for the generic (pointer-sized) type. |
2436 | // |
2437 | // DESCRIPTION: Pop the top stack element, convert it to a |
2438 | // different type, and push the result. |
2439 | case DW_OP_convert: { |
2440 | if (stack.size() < 1) { |
2441 | if (error_ptr) |
2442 | error_ptr->SetErrorString( |
2443 | "Expression stack needs at least 1 item for DW_OP_convert."); |
2444 | return false; |
2445 | } |
2446 | const uint64_t die_offset = opcodes.GetULEB128(&offset); |
2447 | uint64_t bit_size; |
2448 | bool sign; |
2449 | if (die_offset == 0) { |
2450 | // The generic type has the size of an address on the target |
2451 | // machine and an unspecified signedness. Scalar has no |
2452 | // "unspecified signedness", so we use unsigned types. |
2453 | if (!module_sp) { |
2454 | if (error_ptr) |
2455 | error_ptr->SetErrorString("No module"); |
2456 | return false; |
2457 | } |
2458 | sign = false; |
2459 | bit_size = module_sp->GetArchitecture().GetAddressByteSize() * 8; |
2460 | if (!bit_size) { |
2461 | if (error_ptr) |
2462 | error_ptr->SetErrorString("unspecified architecture"); |
2463 | return false; |
2464 | } |
2465 | } else { |
2466 | // Retrieve the type DIE that the value is being converted to. |
2467 | // FIXME: the constness has annoying ripple effects. |
2468 | DWARFDIE die = const_cast<DWARFUnit *>(dwarf_cu)->GetDIE(die_offset); |
2469 | if (!die) { |
2470 | if (error_ptr) |
2471 | error_ptr->SetErrorString("Cannot resolve DW_OP_convert type DIE"); |
2472 | return false; |
2473 | } |
2474 | uint64_t encoding = |
2475 | die.GetAttributeValueAsUnsigned(DW_AT_encoding, DW_ATE_hi_user); |
2476 | bit_size = die.GetAttributeValueAsUnsigned(DW_AT_byte_size, 0) * 8; |
2477 | if (!bit_size) |
2478 | bit_size = die.GetAttributeValueAsUnsigned(DW_AT_bit_size, 0); |
2479 | if (!bit_size) { |
2480 | if (error_ptr) |
2481 | error_ptr->SetErrorString("Unsupported type size in DW_OP_convert"); |
2482 | return false; |
2483 | } |
2484 | switch (encoding) { |
2485 | case DW_ATE_signed: |
2486 | case DW_ATE_signed_char: |
2487 | sign = true; |
2488 | break; |
2489 | case DW_ATE_unsigned: |
2490 | case DW_ATE_unsigned_char: |
2491 | sign = false; |
2492 | break; |
2493 | default: |
2494 | if (error_ptr) |
2495 | error_ptr->SetErrorString("Unsupported encoding in DW_OP_convert"); |
2496 | return false; |
2497 | } |
2498 | } |
2499 | Scalar &top = stack.back().ResolveValue(exe_ctx); |
2500 | top.TruncOrExtendTo(bit_size, sign); |
2501 | break; |
2502 | } |
2503 | |
2504 | // OPCODE: DW_OP_call_frame_cfa |
2505 | // OPERANDS: None |
2506 | // DESCRIPTION: Specifies a DWARF expression that pushes the value of |
2507 | // the canonical frame address consistent with the call frame information |
2508 | // located in .debug_frame (or in the FDEs of the eh_frame section). |
2509 | case DW_OP_call_frame_cfa: |
2510 | if (frame) { |
2511 | // Note that we don't have to parse FDEs because this DWARF expression |
2512 | // is commonly evaluated with a valid stack frame. |
2513 | StackID id = frame->GetStackID(); |
2514 | addr_t cfa = id.GetCallFrameAddress(); |
2515 | if (cfa != LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
2516 | stack.push_back(Scalar(cfa)); |
2517 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2518 | } else if (error_ptr) |
2519 | error_ptr->SetErrorString("Stack frame does not include a canonical " |
2520 | "frame address for DW_OP_call_frame_cfa " |
2521 | "opcode."); |
2522 | } else { |
2523 | if (error_ptr) |
2524 | error_ptr->SetErrorString("Invalid stack frame in context for " |
2525 | "DW_OP_call_frame_cfa opcode."); |
2526 | return false; |
2527 | } |
2528 | break; |
2529 | |
2530 | // OPCODE: DW_OP_form_tls_address (or the old pre-DWARFv3 vendor extension |
2531 | // opcode, DW_OP_GNU_push_tls_address) |
2532 | // OPERANDS: none |
2533 | // DESCRIPTION: Pops a TLS offset from the stack, converts it to |
2534 | // an address in the current thread's thread-local storage block, and |
2535 | // pushes it on the stack. |
2536 | case DW_OP_form_tls_address: |
2537 | case DW_OP_GNU_push_tls_address: { |
2538 | if (stack.size() < 1) { |
2539 | if (error_ptr) { |
2540 | if (op == DW_OP_form_tls_address) |
2541 | error_ptr->SetErrorString( |
2542 | "DW_OP_form_tls_address needs an argument."); |
2543 | else |
2544 | error_ptr->SetErrorString( |
2545 | "DW_OP_GNU_push_tls_address needs an argument."); |
2546 | } |
2547 | return false; |
2548 | } |
2549 | |
2550 | if (!exe_ctx || !module_sp) { |
2551 | if (error_ptr) |
2552 | error_ptr->SetErrorString("No context to evaluate TLS within."); |
2553 | return false; |
2554 | } |
2555 | |
2556 | Thread *thread = exe_ctx->GetThreadPtr(); |
2557 | if (!thread) { |
2558 | if (error_ptr) |
2559 | error_ptr->SetErrorString("No thread to evaluate TLS within."); |
2560 | return false; |
2561 | } |
2562 | |
2563 | // Lookup the TLS block address for this thread and module. |
2564 | const addr_t tls_file_addr = |
2565 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
2566 | const addr_t tls_load_addr = |
2567 | thread->GetThreadLocalData(module_sp, tls_file_addr); |
2568 | |
2569 | if (tls_load_addr == LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
2570 | if (error_ptr) |
2571 | error_ptr->SetErrorString( |
2572 | "No TLS data currently exists for this thread."); |
2573 | return false; |
2574 | } |
2575 | |
2576 | stack.back().GetScalar() = tls_load_addr; |
2577 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2578 | } break; |
2579 | |
2580 | // OPCODE: DW_OP_addrx (DW_OP_GNU_addr_index is the legacy name.) |
2581 | // OPERANDS: 1 |
2582 | // ULEB128: index to the .debug_addr section |
2583 | // DESCRIPTION: Pushes an address to the stack from the .debug_addr |
2584 | // section with the base address specified by the DW_AT_addr_base attribute |
2585 | // and the 0 based index is the ULEB128 encoded index. |
2586 | case DW_OP_addrx: |
2587 | case DW_OP_GNU_addr_index: { |
2588 | if (!dwarf_cu) { |
2589 | if (error_ptr) |
2590 | error_ptr->SetErrorString("DW_OP_GNU_addr_index found without a " |
2591 | "compile unit being specified"); |
2592 | return false; |
2593 | } |
2594 | uint64_t index = opcodes.GetULEB128(&offset); |
2595 | lldb::addr_t value = ReadAddressFromDebugAddrSection(dwarf_cu, index); |
2596 | stack.push_back(Scalar(value)); |
2597 | stack.back().SetValueType(Value::ValueType::FileAddress); |
2598 | } break; |
2599 | |
2600 | // OPCODE: DW_OP_GNU_const_index |
2601 | // OPERANDS: 1 |
2602 | // ULEB128: index to the .debug_addr section |
2603 | // DESCRIPTION: Pushes an constant with the size of a machine address to |
2604 | // the stack from the .debug_addr section with the base address specified |
2605 | // by the DW_AT_addr_base attribute and the 0 based index is the ULEB128 |
2606 | // encoded index. |
2607 | case DW_OP_GNU_const_index: { |
2608 | if (!dwarf_cu) { |
2609 | if (error_ptr) |
2610 | error_ptr->SetErrorString("DW_OP_GNU_const_index found without a " |
2611 | "compile unit being specified"); |
2612 | return false; |
2613 | } |
2614 | uint64_t index = opcodes.GetULEB128(&offset); |
2615 | lldb::addr_t value = ReadAddressFromDebugAddrSection(dwarf_cu, index); |
2616 | stack.push_back(Scalar(value)); |
2617 | } break; |
2618 | |
2619 | case DW_OP_GNU_entry_value: |
2620 | case DW_OP_entry_value: { |
2621 | if (!Evaluate_DW_OP_entry_value(stack, exe_ctx, reg_ctx, opcodes, offset, |
2622 | error_ptr, log)) { |
2623 | LLDB_ERRORF(error_ptr, "Could not evaluate %s.",do { if (error_ptr) { (error_ptr)->SetErrorStringWithFormat (("Could not evaluate %s."), DW_OP_value_to_name(op)); } } while (0); |
2624 | DW_OP_value_to_name(op))do { if (error_ptr) { (error_ptr)->SetErrorStringWithFormat (("Could not evaluate %s."), DW_OP_value_to_name(op)); } } while (0);; |
2625 | return false; |
2626 | } |
2627 | break; |
2628 | } |
2629 | |
2630 | default: |
2631 | if (error_ptr) |
2632 | error_ptr->SetErrorStringWithFormatv( |
2633 | "Unhandled opcode {0} in DWARFExpression", LocationAtom(op)); |
2634 | return false; |
2635 | } |
2636 | } |
2637 | |
2638 | if (stack.empty()) { |
2639 | // Nothing on the stack, check if we created a piece value from DW_OP_piece |
2640 | // or DW_OP_bit_piece opcodes |
2641 | if (pieces.GetBuffer().GetByteSize()) { |
2642 | result = pieces; |
2643 | return true; |
2644 | } |
2645 | if (error_ptr) |
2646 | error_ptr->SetErrorString("Stack empty after evaluation."); |
2647 | return false; |
2648 | } |
2649 | |
2650 | UpdateValueTypeFromLocationDescription( |
2651 | log, dwarf_cu, dwarf4_location_description_kind, &stack.back()); |
2652 | |
2653 | if (log && log->GetVerbose()) { |
2654 | size_t count = stack.size(); |
2655 | LLDB_LOGF(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack after operation has %" "l" "u" " values:", (uint64_t)count); } while (0) |
2656 | "Stack after operation has %" PRIu64 " values:", (uint64_t)count)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack after operation has %" "l" "u" " values:", (uint64_t)count); } while (0); |
2657 | for (size_t i = 0; i < count; ++i) { |
2658 | StreamString new_value; |
2659 | new_value.Printf("[%" PRIu64"l" "u" "]", (uint64_t)i); |
2660 | stack[i].Dump(&new_value); |
2661 | LLDB_LOGF(log, " %s", new_value.GetData())do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(" %s", new_value.GetData()); } while (0); |
2662 | } |
2663 | } |
2664 | result = stack.back(); |
2665 | return true; // Return true on success |
2666 | } |
2667 | |
2668 | static DataExtractor ToDataExtractor(const llvm::DWARFLocationExpression &loc, |
2669 | ByteOrder byte_order, uint32_t addr_size) { |
2670 | auto buffer_sp = |
2671 | std::make_shared<DataBufferHeap>(loc.Expr.data(), loc.Expr.size()); |
2672 | return DataExtractor(buffer_sp, byte_order, addr_size); |
2673 | } |
2674 | |
2675 | bool DWARFExpression::DumpLocations(Stream *s, lldb::DescriptionLevel level, |
2676 | addr_t load_function_start, addr_t addr, |
2677 | ABI *abi) { |
2678 | if (!IsLocationList()) { |
2679 | DumpLocation(s, m_data, level, abi); |
2680 | return true; |
2681 | } |
2682 | bool dump_all = addr == LLDB_INVALID_ADDRESS(18446744073709551615UL); |
2683 | llvm::ListSeparator separator; |
2684 | auto callback = [&](llvm::DWARFLocationExpression loc) -> bool { |
2685 | if (loc.Range && |
2686 | (dump_all || (loc.Range->LowPC <= addr && addr < loc.Range->HighPC))) { |
2687 | uint32_t addr_size = m_data.GetAddressByteSize(); |
2688 | DataExtractor data = ToDataExtractor(loc, m_data.GetByteOrder(), |
2689 | m_data.GetAddressByteSize()); |
2690 | s->AsRawOstream() << separator; |
2691 | s->PutCString("["); |
2692 | s->AsRawOstream() << llvm::format_hex(loc.Range->LowPC, |
2693 | 2 + 2 * addr_size); |
2694 | s->PutCString(", "); |
2695 | s->AsRawOstream() << llvm::format_hex(loc.Range->HighPC, |
2696 | 2 + 2 * addr_size); |
2697 | s->PutCString(") -> "); |
2698 | DumpLocation(s, data, level, abi); |
2699 | return dump_all; |
2700 | } |
2701 | return true; |
2702 | }; |
2703 | if (!GetLocationExpressions(load_function_start, callback)) |
2704 | return false; |
2705 | return true; |
2706 | } |
2707 | |
2708 | bool DWARFExpression::GetLocationExpressions( |
2709 | addr_t load_function_start, |
2710 | llvm::function_ref<bool(llvm::DWARFLocationExpression)> callback) const { |
2711 | if (load_function_start == LLDB_INVALID_ADDRESS(18446744073709551615UL)) |
2712 | return false; |
2713 | |
2714 | Log *log = GetLog(LLDBLog::Expressions); |
2715 | |
2716 | std::unique_ptr<llvm::DWARFLocationTable> loctable_up = |
2717 | m_dwarf_cu->GetLocationTable(m_data); |
2718 | |
2719 | uint64_t offset = 0; |
2720 | auto lookup_addr = |
2721 | [&](uint32_t index) -> llvm::Optional<llvm::object::SectionedAddress> { |
2722 | addr_t address = ReadAddressFromDebugAddrSection(m_dwarf_cu, index); |
2723 | if (address == LLDB_INVALID_ADDRESS(18446744073709551615UL)) |
2724 | return llvm::None; |
2725 | return llvm::object::SectionedAddress{address}; |
2726 | }; |
2727 | auto process_list = [&](llvm::Expected<llvm::DWARFLocationExpression> loc) { |
2728 | if (!loc) { |
2729 | LLDB_LOG_ERROR(log, loc.takeError(), "{0}")do { ::lldb_private::Log *log_private = (log); ::llvm::Error error_private = (loc.takeError()); if (log_private && error_private ) { log_private->FormatError(::std::move(error_private), "lldb/source/Expression/DWARFExpression.cpp" , __func__, "{0}"); } else ::llvm::consumeError(::std::move(error_private )); } while (0); |
2730 | return true; |
2731 | } |
2732 | if (loc->Range) { |
2733 | // This relocates low_pc and high_pc by adding the difference between the |
2734 | // function file address, and the actual address it is loaded in memory. |
2735 | addr_t slide = load_function_start - m_loclist_addresses->func_file_addr; |
2736 | loc->Range->LowPC += slide; |
2737 | loc->Range->HighPC += slide; |
2738 | } |
2739 | return callback(*loc); |
2740 | }; |
2741 | llvm::Error error = loctable_up->visitAbsoluteLocationList( |
2742 | offset, llvm::object::SectionedAddress{m_loclist_addresses->cu_file_addr}, |
2743 | lookup_addr, process_list); |
2744 | if (error) { |
2745 | LLDB_LOG_ERROR(log, std::move(error), "{0}")do { ::lldb_private::Log *log_private = (log); ::llvm::Error error_private = (std::move(error)); if (log_private && error_private ) { log_private->FormatError(::std::move(error_private), "lldb/source/Expression/DWARFExpression.cpp" , __func__, "{0}"); } else ::llvm::consumeError(::std::move(error_private )); } while (0); |
2746 | return false; |
2747 | } |
2748 | return true; |
2749 | } |
2750 | |
2751 | llvm::Optional<DataExtractor> |
2752 | DWARFExpression::GetLocationExpression(addr_t load_function_start, |
2753 | addr_t addr) const { |
2754 | llvm::Optional<DataExtractor> data; |
2755 | auto callback = [&](llvm::DWARFLocationExpression loc) { |
2756 | if (loc.Range && loc.Range->LowPC <= addr && addr < loc.Range->HighPC) { |
2757 | data = ToDataExtractor(loc, m_data.GetByteOrder(), |
2758 | m_data.GetAddressByteSize()); |
2759 | } |
2760 | return !data; |
2761 | }; |
2762 | GetLocationExpressions(load_function_start, callback); |
2763 | return data; |
2764 | } |
2765 | |
2766 | bool DWARFExpression::MatchesOperand(StackFrame &frame, |
2767 | const Instruction::Operand &operand) { |
2768 | using namespace OperandMatchers; |
2769 | |
2770 | RegisterContextSP reg_ctx_sp = frame.GetRegisterContext(); |
2771 | if (!reg_ctx_sp) { |
2772 | return false; |
2773 | } |
2774 | |
2775 | DataExtractor opcodes; |
2776 | if (IsLocationList()) { |
2777 | SymbolContext sc = frame.GetSymbolContext(eSymbolContextFunction); |
2778 | if (!sc.function) |
2779 | return false; |
2780 | |
2781 | addr_t load_function_start = |
2782 | sc.function->GetAddressRange().GetBaseAddress().GetFileAddress(); |
2783 | if (load_function_start == LLDB_INVALID_ADDRESS(18446744073709551615UL)) |
2784 | return false; |
2785 | |
2786 | addr_t pc = frame.GetFrameCodeAddress().GetLoadAddress( |
2787 | frame.CalculateTarget().get()); |
2788 | |
2789 | if (llvm::Optional<DataExtractor> expr = |
2790 | GetLocationExpression(load_function_start, pc)) |
2791 | opcodes = std::move(*expr); |
2792 | else |
2793 | return false; |
2794 | } else |
2795 | opcodes = m_data; |
2796 | |
2797 | |
2798 | lldb::offset_t op_offset = 0; |
2799 | uint8_t opcode = opcodes.GetU8(&op_offset); |
2800 | |
2801 | if (opcode == DW_OP_fbreg) { |
2802 | int64_t offset = opcodes.GetSLEB128(&op_offset); |
2803 | |
2804 | DWARFExpression *fb_expr = frame.GetFrameBaseExpression(nullptr); |
2805 | if (!fb_expr) { |
2806 | return false; |
2807 | } |
2808 | |
2809 | auto recurse = [&frame, fb_expr](const Instruction::Operand &child) { |
2810 | return fb_expr->MatchesOperand(frame, child); |
2811 | }; |
2812 | |
2813 | if (!offset && |
2814 | MatchUnaryOp(MatchOpType(Instruction::Operand::Type::Dereference), |
2815 | recurse)(operand)) { |
2816 | return true; |
2817 | } |
2818 | |
2819 | return MatchUnaryOp( |
2820 | MatchOpType(Instruction::Operand::Type::Dereference), |
2821 | MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum), |
2822 | MatchImmOp(offset), recurse))(operand); |
2823 | } |
2824 | |
2825 | bool dereference = false; |
2826 | const RegisterInfo *reg = nullptr; |
2827 | int64_t offset = 0; |
2828 | |
2829 | if (opcode >= DW_OP_reg0 && opcode <= DW_OP_reg31) { |
2830 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, opcode - DW_OP_reg0); |
2831 | } else if (opcode >= DW_OP_breg0 && opcode <= DW_OP_breg31) { |
2832 | offset = opcodes.GetSLEB128(&op_offset); |
2833 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, opcode - DW_OP_breg0); |
2834 | } else if (opcode == DW_OP_regx) { |
2835 | uint32_t reg_num = static_cast<uint32_t>(opcodes.GetULEB128(&op_offset)); |
2836 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, reg_num); |
2837 | } else if (opcode == DW_OP_bregx) { |
2838 | uint32_t reg_num = static_cast<uint32_t>(opcodes.GetULEB128(&op_offset)); |
2839 | offset = opcodes.GetSLEB128(&op_offset); |
2840 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, reg_num); |
2841 | } else { |
2842 | return false; |
2843 | } |
2844 | |
2845 | if (!reg) { |
2846 | return false; |
2847 | } |
2848 | |
2849 | if (dereference) { |
2850 | if (!offset && |
2851 | MatchUnaryOp(MatchOpType(Instruction::Operand::Type::Dereference), |
2852 | MatchRegOp(*reg))(operand)) { |
2853 | return true; |
2854 | } |
2855 | |
2856 | return MatchUnaryOp( |
2857 | MatchOpType(Instruction::Operand::Type::Dereference), |
2858 | MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum), |
2859 | MatchRegOp(*reg), |
2860 | MatchImmOp(offset)))(operand); |
2861 | } else { |
2862 | return MatchRegOp(*reg)(operand); |
2863 | } |
2864 | } |