File: | src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp |
Warning: | line 2351, 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/Log.h" |
20 | #include "lldb/Utility/RegisterValue.h" |
21 | #include "lldb/Utility/Scalar.h" |
22 | #include "lldb/Utility/StreamString.h" |
23 | #include "lldb/Utility/VMRange.h" |
24 | |
25 | #include "lldb/Host/Host.h" |
26 | #include "lldb/Utility/Endian.h" |
27 | |
28 | #include "lldb/Symbol/Function.h" |
29 | |
30 | #include "lldb/Target/ABI.h" |
31 | #include "lldb/Target/ExecutionContext.h" |
32 | #include "lldb/Target/Process.h" |
33 | #include "lldb/Target/RegisterContext.h" |
34 | #include "lldb/Target/StackFrame.h" |
35 | #include "lldb/Target/StackID.h" |
36 | #include "lldb/Target/Target.h" |
37 | #include "lldb/Target/Thread.h" |
38 | |
39 | #include "Plugins/SymbolFile/DWARF/DWARFUnit.h" |
40 | |
41 | using namespace lldb; |
42 | using namespace lldb_private; |
43 | |
44 | static lldb::addr_t |
45 | ReadAddressFromDebugAddrSection(const DWARFUnit *dwarf_cu, |
46 | uint32_t index) { |
47 | uint32_t index_size = dwarf_cu->GetAddressByteSize(); |
48 | dw_offset_t addr_base = dwarf_cu->GetAddrBase(); |
49 | lldb::offset_t offset = addr_base + index * index_size; |
50 | const DWARFDataExtractor &data = |
51 | dwarf_cu->GetSymbolFileDWARF().GetDWARFContext().getOrLoadAddrData(); |
52 | if (data.ValidOffsetForDataOfSize(offset, index_size)) |
53 | return data.GetMaxU64_unchecked(&offset, index_size); |
54 | return LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
55 | } |
56 | |
57 | // DWARFExpression constructor |
58 | DWARFExpression::DWARFExpression() : m_module_wp(), m_data() {} |
59 | |
60 | DWARFExpression::DWARFExpression(lldb::ModuleSP module_sp, |
61 | const DataExtractor &data, |
62 | const DWARFUnit *dwarf_cu) |
63 | : m_module_wp(), m_data(data), m_dwarf_cu(dwarf_cu), |
64 | m_reg_kind(eRegisterKindDWARF) { |
65 | if (module_sp) |
66 | m_module_wp = module_sp; |
67 | } |
68 | |
69 | // Destructor |
70 | DWARFExpression::~DWARFExpression() = default; |
71 | |
72 | bool DWARFExpression::IsValid() const { return m_data.GetByteSize() > 0; } |
73 | |
74 | void DWARFExpression::UpdateValue(uint64_t const_value, |
75 | lldb::offset_t const_value_byte_size, |
76 | uint8_t addr_byte_size) { |
77 | if (!const_value_byte_size) |
78 | return; |
79 | |
80 | m_data.SetData( |
81 | DataBufferSP(new DataBufferHeap(&const_value, const_value_byte_size))); |
82 | m_data.SetByteOrder(endian::InlHostByteOrder()); |
83 | m_data.SetAddressByteSize(addr_byte_size); |
84 | } |
85 | |
86 | void DWARFExpression::DumpLocation(Stream *s, const DataExtractor &data, |
87 | lldb::DescriptionLevel level, |
88 | ABI *abi) const { |
89 | llvm::DWARFExpression(data.GetAsLLVM(), data.GetAddressByteSize()) |
90 | .print(s->AsRawOstream(), llvm::DIDumpOptions(), |
91 | abi ? &abi->GetMCRegisterInfo() : nullptr, nullptr); |
92 | } |
93 | |
94 | void DWARFExpression::SetLocationListAddresses(addr_t cu_file_addr, |
95 | addr_t func_file_addr) { |
96 | m_loclist_addresses = LoclistAddresses{cu_file_addr, func_file_addr}; |
97 | } |
98 | |
99 | int DWARFExpression::GetRegisterKind() { return m_reg_kind; } |
100 | |
101 | void DWARFExpression::SetRegisterKind(RegisterKind reg_kind) { |
102 | m_reg_kind = reg_kind; |
103 | } |
104 | |
105 | bool DWARFExpression::IsLocationList() const { |
106 | return bool(m_loclist_addresses); |
107 | } |
108 | |
109 | namespace { |
110 | /// Implement enough of the DWARFObject interface in order to be able to call |
111 | /// DWARFLocationTable::dumpLocationList. We don't have access to a real |
112 | /// DWARFObject here because DWARFExpression is used in non-DWARF scenarios too. |
113 | class DummyDWARFObject final: public llvm::DWARFObject { |
114 | public: |
115 | DummyDWARFObject(bool IsLittleEndian) : IsLittleEndian(IsLittleEndian) {} |
116 | |
117 | bool isLittleEndian() const override { return IsLittleEndian; } |
118 | |
119 | llvm::Optional<llvm::RelocAddrEntry> find(const llvm::DWARFSection &Sec, |
120 | uint64_t Pos) const override { |
121 | return llvm::None; |
122 | } |
123 | private: |
124 | bool IsLittleEndian; |
125 | }; |
126 | } |
127 | |
128 | void DWARFExpression::GetDescription(Stream *s, lldb::DescriptionLevel level, |
129 | addr_t location_list_base_addr, |
130 | ABI *abi) const { |
131 | if (IsLocationList()) { |
132 | // We have a location list |
133 | lldb::offset_t offset = 0; |
134 | std::unique_ptr<llvm::DWARFLocationTable> loctable_up = |
135 | m_dwarf_cu->GetLocationTable(m_data); |
136 | |
137 | llvm::MCRegisterInfo *MRI = abi ? &abi->GetMCRegisterInfo() : nullptr; |
138 | llvm::DIDumpOptions DumpOpts; |
139 | DumpOpts.RecoverableErrorHandler = [&](llvm::Error E) { |
140 | s->AsRawOstream() << "error: " << toString(std::move(E)); |
141 | }; |
142 | loctable_up->dumpLocationList( |
143 | &offset, s->AsRawOstream(), |
144 | llvm::object::SectionedAddress{m_loclist_addresses->cu_file_addr}, MRI, |
145 | DummyDWARFObject(m_data.GetByteOrder() == eByteOrderLittle), nullptr, |
146 | DumpOpts, s->GetIndentLevel() + 2); |
147 | } else { |
148 | // We have a normal location that contains DW_OP location opcodes |
149 | DumpLocation(s, m_data, level, abi); |
150 | } |
151 | } |
152 | |
153 | static bool ReadRegisterValueAsScalar(RegisterContext *reg_ctx, |
154 | lldb::RegisterKind reg_kind, |
155 | uint32_t reg_num, Status *error_ptr, |
156 | Value &value) { |
157 | if (reg_ctx == nullptr) { |
158 | if (error_ptr) |
159 | error_ptr->SetErrorString("No register context in frame.\n"); |
160 | } else { |
161 | uint32_t native_reg = |
162 | reg_ctx->ConvertRegisterKindToRegisterNumber(reg_kind, reg_num); |
163 | if (native_reg == LLDB_INVALID_REGNUM0xffffffffU) { |
164 | if (error_ptr) |
165 | error_ptr->SetErrorStringWithFormat("Unable to convert register " |
166 | "kind=%u reg_num=%u to a native " |
167 | "register number.\n", |
168 | reg_kind, reg_num); |
169 | } else { |
170 | const RegisterInfo *reg_info = |
171 | reg_ctx->GetRegisterInfoAtIndex(native_reg); |
172 | RegisterValue reg_value; |
173 | if (reg_ctx->ReadRegister(reg_info, reg_value)) { |
174 | if (reg_value.GetScalarValue(value.GetScalar())) { |
175 | value.SetValueType(Value::ValueType::Scalar); |
176 | value.SetContext(Value::ContextType::RegisterInfo, |
177 | const_cast<RegisterInfo *>(reg_info)); |
178 | if (error_ptr) |
179 | error_ptr->Clear(); |
180 | return true; |
181 | } else { |
182 | // If we get this error, then we need to implement a value buffer in |
183 | // the dwarf expression evaluation function... |
184 | if (error_ptr) |
185 | error_ptr->SetErrorStringWithFormat( |
186 | "register %s can't be converted to a scalar value", |
187 | reg_info->name); |
188 | } |
189 | } else { |
190 | if (error_ptr) |
191 | error_ptr->SetErrorStringWithFormat("register %s is not available", |
192 | reg_info->name); |
193 | } |
194 | } |
195 | } |
196 | return false; |
197 | } |
198 | |
199 | /// Return the length in bytes of the set of operands for \p op. No guarantees |
200 | /// are made on the state of \p data after this call. |
201 | static offset_t GetOpcodeDataSize(const DataExtractor &data, |
202 | const lldb::offset_t data_offset, |
203 | const uint8_t op) { |
204 | lldb::offset_t offset = data_offset; |
205 | switch (op) { |
206 | case DW_OP_addr: |
207 | case DW_OP_call_ref: // 0x9a 1 address sized offset of DIE (DWARF3) |
208 | return data.GetAddressByteSize(); |
209 | |
210 | // Opcodes with no arguments |
211 | case DW_OP_deref: // 0x06 |
212 | case DW_OP_dup: // 0x12 |
213 | case DW_OP_drop: // 0x13 |
214 | case DW_OP_over: // 0x14 |
215 | case DW_OP_swap: // 0x16 |
216 | case DW_OP_rot: // 0x17 |
217 | case DW_OP_xderef: // 0x18 |
218 | case DW_OP_abs: // 0x19 |
219 | case DW_OP_and: // 0x1a |
220 | case DW_OP_div: // 0x1b |
221 | case DW_OP_minus: // 0x1c |
222 | case DW_OP_mod: // 0x1d |
223 | case DW_OP_mul: // 0x1e |
224 | case DW_OP_neg: // 0x1f |
225 | case DW_OP_not: // 0x20 |
226 | case DW_OP_or: // 0x21 |
227 | case DW_OP_plus: // 0x22 |
228 | case DW_OP_shl: // 0x24 |
229 | case DW_OP_shr: // 0x25 |
230 | case DW_OP_shra: // 0x26 |
231 | case DW_OP_xor: // 0x27 |
232 | case DW_OP_eq: // 0x29 |
233 | case DW_OP_ge: // 0x2a |
234 | case DW_OP_gt: // 0x2b |
235 | case DW_OP_le: // 0x2c |
236 | case DW_OP_lt: // 0x2d |
237 | case DW_OP_ne: // 0x2e |
238 | case DW_OP_lit0: // 0x30 |
239 | case DW_OP_lit1: // 0x31 |
240 | case DW_OP_lit2: // 0x32 |
241 | case DW_OP_lit3: // 0x33 |
242 | case DW_OP_lit4: // 0x34 |
243 | case DW_OP_lit5: // 0x35 |
244 | case DW_OP_lit6: // 0x36 |
245 | case DW_OP_lit7: // 0x37 |
246 | case DW_OP_lit8: // 0x38 |
247 | case DW_OP_lit9: // 0x39 |
248 | case DW_OP_lit10: // 0x3A |
249 | case DW_OP_lit11: // 0x3B |
250 | case DW_OP_lit12: // 0x3C |
251 | case DW_OP_lit13: // 0x3D |
252 | case DW_OP_lit14: // 0x3E |
253 | case DW_OP_lit15: // 0x3F |
254 | case DW_OP_lit16: // 0x40 |
255 | case DW_OP_lit17: // 0x41 |
256 | case DW_OP_lit18: // 0x42 |
257 | case DW_OP_lit19: // 0x43 |
258 | case DW_OP_lit20: // 0x44 |
259 | case DW_OP_lit21: // 0x45 |
260 | case DW_OP_lit22: // 0x46 |
261 | case DW_OP_lit23: // 0x47 |
262 | case DW_OP_lit24: // 0x48 |
263 | case DW_OP_lit25: // 0x49 |
264 | case DW_OP_lit26: // 0x4A |
265 | case DW_OP_lit27: // 0x4B |
266 | case DW_OP_lit28: // 0x4C |
267 | case DW_OP_lit29: // 0x4D |
268 | case DW_OP_lit30: // 0x4E |
269 | case DW_OP_lit31: // 0x4f |
270 | case DW_OP_reg0: // 0x50 |
271 | case DW_OP_reg1: // 0x51 |
272 | case DW_OP_reg2: // 0x52 |
273 | case DW_OP_reg3: // 0x53 |
274 | case DW_OP_reg4: // 0x54 |
275 | case DW_OP_reg5: // 0x55 |
276 | case DW_OP_reg6: // 0x56 |
277 | case DW_OP_reg7: // 0x57 |
278 | case DW_OP_reg8: // 0x58 |
279 | case DW_OP_reg9: // 0x59 |
280 | case DW_OP_reg10: // 0x5A |
281 | case DW_OP_reg11: // 0x5B |
282 | case DW_OP_reg12: // 0x5C |
283 | case DW_OP_reg13: // 0x5D |
284 | case DW_OP_reg14: // 0x5E |
285 | case DW_OP_reg15: // 0x5F |
286 | case DW_OP_reg16: // 0x60 |
287 | case DW_OP_reg17: // 0x61 |
288 | case DW_OP_reg18: // 0x62 |
289 | case DW_OP_reg19: // 0x63 |
290 | case DW_OP_reg20: // 0x64 |
291 | case DW_OP_reg21: // 0x65 |
292 | case DW_OP_reg22: // 0x66 |
293 | case DW_OP_reg23: // 0x67 |
294 | case DW_OP_reg24: // 0x68 |
295 | case DW_OP_reg25: // 0x69 |
296 | case DW_OP_reg26: // 0x6A |
297 | case DW_OP_reg27: // 0x6B |
298 | case DW_OP_reg28: // 0x6C |
299 | case DW_OP_reg29: // 0x6D |
300 | case DW_OP_reg30: // 0x6E |
301 | case DW_OP_reg31: // 0x6F |
302 | case DW_OP_nop: // 0x96 |
303 | case DW_OP_push_object_address: // 0x97 DWARF3 |
304 | case DW_OP_form_tls_address: // 0x9b DWARF3 |
305 | case DW_OP_call_frame_cfa: // 0x9c DWARF3 |
306 | case DW_OP_stack_value: // 0x9f DWARF4 |
307 | case DW_OP_GNU_push_tls_address: // 0xe0 GNU extension |
308 | return 0; |
309 | |
310 | // Opcodes with a single 1 byte arguments |
311 | case DW_OP_const1u: // 0x08 1 1-byte constant |
312 | case DW_OP_const1s: // 0x09 1 1-byte constant |
313 | case DW_OP_pick: // 0x15 1 1-byte stack index |
314 | case DW_OP_deref_size: // 0x94 1 1-byte size of data retrieved |
315 | case DW_OP_xderef_size: // 0x95 1 1-byte size of data retrieved |
316 | return 1; |
317 | |
318 | // Opcodes with a single 2 byte arguments |
319 | case DW_OP_const2u: // 0x0a 1 2-byte constant |
320 | case DW_OP_const2s: // 0x0b 1 2-byte constant |
321 | case DW_OP_skip: // 0x2f 1 signed 2-byte constant |
322 | case DW_OP_bra: // 0x28 1 signed 2-byte constant |
323 | case DW_OP_call2: // 0x98 1 2-byte offset of DIE (DWARF3) |
324 | return 2; |
325 | |
326 | // Opcodes with a single 4 byte arguments |
327 | case DW_OP_const4u: // 0x0c 1 4-byte constant |
328 | case DW_OP_const4s: // 0x0d 1 4-byte constant |
329 | case DW_OP_call4: // 0x99 1 4-byte offset of DIE (DWARF3) |
330 | return 4; |
331 | |
332 | // Opcodes with a single 8 byte arguments |
333 | case DW_OP_const8u: // 0x0e 1 8-byte constant |
334 | case DW_OP_const8s: // 0x0f 1 8-byte constant |
335 | return 8; |
336 | |
337 | // All opcodes that have a single ULEB (signed or unsigned) argument |
338 | case DW_OP_addrx: // 0xa1 1 ULEB128 index |
339 | case DW_OP_constu: // 0x10 1 ULEB128 constant |
340 | case DW_OP_consts: // 0x11 1 SLEB128 constant |
341 | case DW_OP_plus_uconst: // 0x23 1 ULEB128 addend |
342 | case DW_OP_breg0: // 0x70 1 ULEB128 register |
343 | case DW_OP_breg1: // 0x71 1 ULEB128 register |
344 | case DW_OP_breg2: // 0x72 1 ULEB128 register |
345 | case DW_OP_breg3: // 0x73 1 ULEB128 register |
346 | case DW_OP_breg4: // 0x74 1 ULEB128 register |
347 | case DW_OP_breg5: // 0x75 1 ULEB128 register |
348 | case DW_OP_breg6: // 0x76 1 ULEB128 register |
349 | case DW_OP_breg7: // 0x77 1 ULEB128 register |
350 | case DW_OP_breg8: // 0x78 1 ULEB128 register |
351 | case DW_OP_breg9: // 0x79 1 ULEB128 register |
352 | case DW_OP_breg10: // 0x7a 1 ULEB128 register |
353 | case DW_OP_breg11: // 0x7b 1 ULEB128 register |
354 | case DW_OP_breg12: // 0x7c 1 ULEB128 register |
355 | case DW_OP_breg13: // 0x7d 1 ULEB128 register |
356 | case DW_OP_breg14: // 0x7e 1 ULEB128 register |
357 | case DW_OP_breg15: // 0x7f 1 ULEB128 register |
358 | case DW_OP_breg16: // 0x80 1 ULEB128 register |
359 | case DW_OP_breg17: // 0x81 1 ULEB128 register |
360 | case DW_OP_breg18: // 0x82 1 ULEB128 register |
361 | case DW_OP_breg19: // 0x83 1 ULEB128 register |
362 | case DW_OP_breg20: // 0x84 1 ULEB128 register |
363 | case DW_OP_breg21: // 0x85 1 ULEB128 register |
364 | case DW_OP_breg22: // 0x86 1 ULEB128 register |
365 | case DW_OP_breg23: // 0x87 1 ULEB128 register |
366 | case DW_OP_breg24: // 0x88 1 ULEB128 register |
367 | case DW_OP_breg25: // 0x89 1 ULEB128 register |
368 | case DW_OP_breg26: // 0x8a 1 ULEB128 register |
369 | case DW_OP_breg27: // 0x8b 1 ULEB128 register |
370 | case DW_OP_breg28: // 0x8c 1 ULEB128 register |
371 | case DW_OP_breg29: // 0x8d 1 ULEB128 register |
372 | case DW_OP_breg30: // 0x8e 1 ULEB128 register |
373 | case DW_OP_breg31: // 0x8f 1 ULEB128 register |
374 | case DW_OP_regx: // 0x90 1 ULEB128 register |
375 | case DW_OP_fbreg: // 0x91 1 SLEB128 offset |
376 | case DW_OP_piece: // 0x93 1 ULEB128 size of piece addressed |
377 | case DW_OP_GNU_addr_index: // 0xfb 1 ULEB128 index |
378 | case DW_OP_GNU_const_index: // 0xfc 1 ULEB128 index |
379 | data.Skip_LEB128(&offset); |
380 | return offset - data_offset; |
381 | |
382 | // All opcodes that have a 2 ULEB (signed or unsigned) arguments |
383 | case DW_OP_bregx: // 0x92 2 ULEB128 register followed by SLEB128 offset |
384 | case DW_OP_bit_piece: // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3); |
385 | data.Skip_LEB128(&offset); |
386 | data.Skip_LEB128(&offset); |
387 | return offset - data_offset; |
388 | |
389 | case DW_OP_implicit_value: // 0x9e ULEB128 size followed by block of that size |
390 | // (DWARF4) |
391 | { |
392 | uint64_t block_len = data.Skip_LEB128(&offset); |
393 | offset += block_len; |
394 | return offset - data_offset; |
395 | } |
396 | |
397 | case DW_OP_GNU_entry_value: |
398 | case DW_OP_entry_value: // 0xa3 ULEB128 size + variable-length block |
399 | { |
400 | uint64_t subexpr_len = data.GetULEB128(&offset); |
401 | return (offset - data_offset) + subexpr_len; |
402 | } |
403 | |
404 | default: |
405 | break; |
406 | } |
407 | return LLDB_INVALID_OFFSET0xffffffffffffffffULL; |
408 | } |
409 | |
410 | lldb::addr_t DWARFExpression::GetLocation_DW_OP_addr(uint32_t op_addr_idx, |
411 | bool &error) const { |
412 | error = false; |
413 | if (IsLocationList()) |
414 | return LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
415 | lldb::offset_t offset = 0; |
416 | uint32_t curr_op_addr_idx = 0; |
417 | while (m_data.ValidOffset(offset)) { |
418 | const uint8_t op = m_data.GetU8(&offset); |
419 | |
420 | if (op == DW_OP_addr) { |
421 | const lldb::addr_t op_file_addr = m_data.GetAddress(&offset); |
422 | if (curr_op_addr_idx == op_addr_idx) |
423 | return op_file_addr; |
424 | else |
425 | ++curr_op_addr_idx; |
426 | } else if (op == DW_OP_GNU_addr_index || op == DW_OP_addrx) { |
427 | uint64_t index = m_data.GetULEB128(&offset); |
428 | if (curr_op_addr_idx == op_addr_idx) { |
429 | if (!m_dwarf_cu) { |
430 | error = true; |
431 | break; |
432 | } |
433 | |
434 | return ReadAddressFromDebugAddrSection(m_dwarf_cu, index); |
435 | } else |
436 | ++curr_op_addr_idx; |
437 | } else { |
438 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
439 | if (op_arg_size == LLDB_INVALID_OFFSET0xffffffffffffffffULL) { |
440 | error = true; |
441 | break; |
442 | } |
443 | offset += op_arg_size; |
444 | } |
445 | } |
446 | return LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
447 | } |
448 | |
449 | bool DWARFExpression::Update_DW_OP_addr(lldb::addr_t file_addr) { |
450 | if (IsLocationList()) |
451 | return false; |
452 | lldb::offset_t offset = 0; |
453 | while (m_data.ValidOffset(offset)) { |
454 | const uint8_t op = m_data.GetU8(&offset); |
455 | |
456 | if (op == DW_OP_addr) { |
457 | const uint32_t addr_byte_size = m_data.GetAddressByteSize(); |
458 | // We have to make a copy of the data as we don't know if this data is |
459 | // from a read only memory mapped buffer, so we duplicate all of the data |
460 | // first, then modify it, and if all goes well, we then replace the data |
461 | // for this expression |
462 | |
463 | // So first we copy the data into a heap buffer |
464 | std::unique_ptr<DataBufferHeap> head_data_up( |
465 | new DataBufferHeap(m_data.GetDataStart(), m_data.GetByteSize())); |
466 | |
467 | // Make en encoder so we can write the address into the buffer using the |
468 | // correct byte order (endianness) |
469 | DataEncoder encoder(head_data_up->GetBytes(), head_data_up->GetByteSize(), |
470 | m_data.GetByteOrder(), addr_byte_size); |
471 | |
472 | // Replace the address in the new buffer |
473 | if (encoder.PutUnsigned(offset, addr_byte_size, file_addr) == UINT32_MAX0xffffffffU) |
474 | return false; |
475 | |
476 | // All went well, so now we can reset the data using a shared pointer to |
477 | // the heap data so "m_data" will now correctly manage the heap data. |
478 | m_data.SetData(DataBufferSP(head_data_up.release())); |
479 | return true; |
480 | } else { |
481 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
482 | if (op_arg_size == LLDB_INVALID_OFFSET0xffffffffffffffffULL) |
483 | break; |
484 | offset += op_arg_size; |
485 | } |
486 | } |
487 | return false; |
488 | } |
489 | |
490 | bool DWARFExpression::ContainsThreadLocalStorage() const { |
491 | // We are assuming for now that any thread local variable will not have a |
492 | // location list. This has been true for all thread local variables we have |
493 | // seen so far produced by any compiler. |
494 | if (IsLocationList()) |
495 | return false; |
496 | lldb::offset_t offset = 0; |
497 | while (m_data.ValidOffset(offset)) { |
498 | const uint8_t op = m_data.GetU8(&offset); |
499 | |
500 | if (op == DW_OP_form_tls_address || op == DW_OP_GNU_push_tls_address) |
501 | return true; |
502 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
503 | if (op_arg_size == LLDB_INVALID_OFFSET0xffffffffffffffffULL) |
504 | return false; |
505 | else |
506 | offset += op_arg_size; |
507 | } |
508 | return false; |
509 | } |
510 | bool DWARFExpression::LinkThreadLocalStorage( |
511 | lldb::ModuleSP new_module_sp, |
512 | std::function<lldb::addr_t(lldb::addr_t file_addr)> const |
513 | &link_address_callback) { |
514 | // We are assuming for now that any thread local variable will not have a |
515 | // location list. This has been true for all thread local variables we have |
516 | // seen so far produced by any compiler. |
517 | if (IsLocationList()) |
518 | return false; |
519 | |
520 | const uint32_t addr_byte_size = m_data.GetAddressByteSize(); |
521 | // We have to make a copy of the data as we don't know if this data is from a |
522 | // read only memory mapped buffer, so we duplicate all of the data first, |
523 | // then modify it, and if all goes well, we then replace the data for this |
524 | // expression |
525 | |
526 | // So first we copy the data into a heap buffer |
527 | std::shared_ptr<DataBufferHeap> heap_data_sp( |
528 | new DataBufferHeap(m_data.GetDataStart(), m_data.GetByteSize())); |
529 | |
530 | // Make en encoder so we can write the address into the buffer using the |
531 | // correct byte order (endianness) |
532 | DataEncoder encoder(heap_data_sp->GetBytes(), heap_data_sp->GetByteSize(), |
533 | m_data.GetByteOrder(), addr_byte_size); |
534 | |
535 | lldb::offset_t offset = 0; |
536 | lldb::offset_t const_offset = 0; |
537 | lldb::addr_t const_value = 0; |
538 | size_t const_byte_size = 0; |
539 | while (m_data.ValidOffset(offset)) { |
540 | const uint8_t op = m_data.GetU8(&offset); |
541 | |
542 | bool decoded_data = false; |
543 | switch (op) { |
544 | case DW_OP_const4u: |
545 | // Remember the const offset in case we later have a |
546 | // DW_OP_form_tls_address or DW_OP_GNU_push_tls_address |
547 | const_offset = offset; |
548 | const_value = m_data.GetU32(&offset); |
549 | decoded_data = true; |
550 | const_byte_size = 4; |
551 | break; |
552 | |
553 | case DW_OP_const8u: |
554 | // Remember the const offset in case we later have a |
555 | // DW_OP_form_tls_address or DW_OP_GNU_push_tls_address |
556 | const_offset = offset; |
557 | const_value = m_data.GetU64(&offset); |
558 | decoded_data = true; |
559 | const_byte_size = 8; |
560 | break; |
561 | |
562 | case DW_OP_form_tls_address: |
563 | case DW_OP_GNU_push_tls_address: |
564 | // DW_OP_form_tls_address and DW_OP_GNU_push_tls_address must be preceded |
565 | // by a file address on the stack. We assume that DW_OP_const4u or |
566 | // DW_OP_const8u is used for these values, and we check that the last |
567 | // opcode we got before either of these was DW_OP_const4u or |
568 | // DW_OP_const8u. If so, then we can link the value accodingly. For |
569 | // Darwin, the value in the DW_OP_const4u or DW_OP_const8u is the file |
570 | // address of a structure that contains a function pointer, the pthread |
571 | // key and the offset into the data pointed to by the pthread key. So we |
572 | // must link this address and also set the module of this expression to |
573 | // the new_module_sp so we can resolve the file address correctly |
574 | if (const_byte_size > 0) { |
575 | lldb::addr_t linked_file_addr = link_address_callback(const_value); |
576 | if (linked_file_addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) |
577 | return false; |
578 | // Replace the address in the new buffer |
579 | if (encoder.PutUnsigned(const_offset, const_byte_size, |
580 | linked_file_addr) == UINT32_MAX0xffffffffU) |
581 | return false; |
582 | } |
583 | break; |
584 | |
585 | default: |
586 | const_offset = 0; |
587 | const_value = 0; |
588 | const_byte_size = 0; |
589 | break; |
590 | } |
591 | |
592 | if (!decoded_data) { |
593 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
594 | if (op_arg_size == LLDB_INVALID_OFFSET0xffffffffffffffffULL) |
595 | return false; |
596 | else |
597 | offset += op_arg_size; |
598 | } |
599 | } |
600 | |
601 | // If we linked the TLS address correctly, update the module so that when the |
602 | // expression is evaluated it can resolve the file address to a load address |
603 | // and read the |
604 | // TLS data |
605 | m_module_wp = new_module_sp; |
606 | m_data.SetData(heap_data_sp); |
607 | return true; |
608 | } |
609 | |
610 | bool DWARFExpression::LocationListContainsAddress(addr_t func_load_addr, |
611 | lldb::addr_t addr) const { |
612 | if (func_load_addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL || addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) |
613 | return false; |
614 | |
615 | if (!IsLocationList()) |
616 | return false; |
617 | |
618 | return GetLocationExpression(func_load_addr, addr) != llvm::None; |
619 | } |
620 | |
621 | bool DWARFExpression::DumpLocationForAddress(Stream *s, |
622 | lldb::DescriptionLevel level, |
623 | addr_t func_load_addr, |
624 | addr_t address, ABI *abi) { |
625 | if (!IsLocationList()) { |
626 | DumpLocation(s, m_data, level, abi); |
627 | return true; |
628 | } |
629 | if (llvm::Optional<DataExtractor> expr = |
630 | GetLocationExpression(func_load_addr, address)) { |
631 | DumpLocation(s, *expr, level, abi); |
632 | return true; |
633 | } |
634 | return false; |
635 | } |
636 | |
637 | static bool Evaluate_DW_OP_entry_value(std::vector<Value> &stack, |
638 | ExecutionContext *exe_ctx, |
639 | RegisterContext *reg_ctx, |
640 | const DataExtractor &opcodes, |
641 | lldb::offset_t &opcode_offset, |
642 | Status *error_ptr, Log *log) { |
643 | // DW_OP_entry_value(sub-expr) describes the location a variable had upon |
644 | // function entry: this variable location is presumed to be optimized out at |
645 | // the current PC value. The caller of the function may have call site |
646 | // information that describes an alternate location for the variable (e.g. a |
647 | // constant literal, or a spilled stack value) in the parent frame. |
648 | // |
649 | // Example (this is pseudo-code & pseudo-DWARF, but hopefully illustrative): |
650 | // |
651 | // void child(int &sink, int x) { |
652 | // ... |
653 | // /* "x" gets optimized out. */ |
654 | // |
655 | // /* The location of "x" here is: DW_OP_entry_value($reg2). */ |
656 | // ++sink; |
657 | // } |
658 | // |
659 | // void parent() { |
660 | // int sink; |
661 | // |
662 | // /* |
663 | // * The callsite information emitted here is: |
664 | // * |
665 | // * DW_TAG_call_site |
666 | // * DW_AT_return_pc ... (for "child(sink, 123);") |
667 | // * DW_TAG_call_site_parameter (for "sink") |
668 | // * DW_AT_location ($reg1) |
669 | // * DW_AT_call_value ($SP - 8) |
670 | // * DW_TAG_call_site_parameter (for "x") |
671 | // * DW_AT_location ($reg2) |
672 | // * DW_AT_call_value ($literal 123) |
673 | // * |
674 | // * DW_TAG_call_site |
675 | // * DW_AT_return_pc ... (for "child(sink, 456);") |
676 | // * ... |
677 | // */ |
678 | // child(sink, 123); |
679 | // child(sink, 456); |
680 | // } |
681 | // |
682 | // When the program stops at "++sink" within `child`, the debugger determines |
683 | // the call site by analyzing the return address. Once the call site is found, |
684 | // the debugger determines which parameter is referenced by DW_OP_entry_value |
685 | // and evaluates the corresponding location for that parameter in `parent`. |
686 | |
687 | // 1. Find the function which pushed the current frame onto the stack. |
688 | if ((!exe_ctx || !exe_ctx->HasTargetScope()) || !reg_ctx) { |
689 | 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("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no exe/reg context") ; } while (0); |
690 | return false; |
691 | } |
692 | |
693 | StackFrame *current_frame = exe_ctx->GetFramePtr(); |
694 | Thread *thread = exe_ctx->GetThreadPtr(); |
695 | if (!current_frame || !thread) { |
696 | 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("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no current frame/thread" ); } while (0); |
697 | return false; |
698 | } |
699 | |
700 | Target &target = exe_ctx->GetTargetRef(); |
701 | StackFrameSP parent_frame = nullptr; |
702 | addr_t return_pc = LLDB_INVALID_ADDRESS0xffffffffffffffffULL; |
703 | uint32_t current_frame_idx = current_frame->GetFrameIndex(); |
704 | uint32_t num_frames = thread->GetStackFrameCount(); |
705 | for (uint32_t parent_frame_idx = current_frame_idx + 1; |
706 | parent_frame_idx < num_frames; ++parent_frame_idx) { |
707 | parent_frame = thread->GetStackFrameAtIndex(parent_frame_idx); |
708 | // Require a valid sequence of frames. |
709 | if (!parent_frame) |
710 | break; |
711 | |
712 | // Record the first valid return address, even if this is an inlined frame, |
713 | // in order to look up the associated call edge in the first non-inlined |
714 | // parent frame. |
715 | if (return_pc == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
716 | return_pc = parent_frame->GetFrameCodeAddress().GetLoadAddress(&target); |
717 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0) |
718 | "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0) |
719 | return_pc)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0); |
720 | } |
721 | |
722 | // If we've found an inlined frame, skip it (these have no call site |
723 | // parameters). |
724 | if (parent_frame->IsInlined()) |
725 | continue; |
726 | |
727 | // We've found the first non-inlined parent frame. |
728 | break; |
729 | } |
730 | if (!parent_frame || !parent_frame->GetRegisterContext()) { |
731 | 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("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no parent frame with reg ctx" ); } while (0); |
732 | return false; |
733 | } |
734 | |
735 | Function *parent_func = |
736 | parent_frame->GetSymbolContext(eSymbolContextFunction).function; |
737 | if (!parent_func) { |
738 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no parent function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no parent function") ; } while (0); |
739 | return false; |
740 | } |
741 | |
742 | // 2. Find the call edge in the parent function responsible for creating the |
743 | // current activation. |
744 | Function *current_func = |
745 | current_frame->GetSymbolContext(eSymbolContextFunction).function; |
746 | if (!current_func) { |
747 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no current function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no current function" ); } while (0); |
748 | return false; |
749 | } |
750 | |
751 | CallEdge *call_edge = nullptr; |
752 | ModuleList &modlist = target.GetImages(); |
753 | ExecutionContext parent_exe_ctx = *exe_ctx; |
754 | parent_exe_ctx.SetFrameSP(parent_frame); |
755 | if (!parent_frame->IsArtificial()) { |
756 | // If the parent frame is not artificial, the current activation may be |
757 | // produced by an ambiguous tail call. In this case, refuse to proceed. |
758 | call_edge = parent_func->GetCallEdgeForReturnAddress(return_pc, target); |
759 | if (!call_edge) { |
760 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/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) |
761 | "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("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/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) |
762 | "in parent frame {1}",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/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) |
763 | return_pc, parent_func->GetName())do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/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); |
764 | return false; |
765 | } |
766 | Function *callee_func = call_edge->GetCallee(modlist, parent_exe_ctx); |
767 | if (callee_func != current_func) { |
768 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: ambiguous call sequence, "do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: ambiguous call sequence, " "can't find real parent frame"); } while (0) |
769 | "can't find real parent frame")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: ambiguous call sequence, " "can't find real parent frame"); } while (0); |
770 | return false; |
771 | } |
772 | } else { |
773 | // The StackFrameList solver machinery has deduced that an unambiguous tail |
774 | // call sequence that produced the current activation. The first edge in |
775 | // the parent that points to the current function must be valid. |
776 | for (auto &edge : parent_func->GetTailCallingEdges()) { |
777 | if (edge->GetCallee(modlist, parent_exe_ctx) == current_func) { |
778 | call_edge = edge.get(); |
779 | break; |
780 | } |
781 | } |
782 | } |
783 | if (!call_edge) { |
784 | 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("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent " "to current function"); } while (0) |
785 | "to current function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent " "to current function"); } while (0); |
786 | return false; |
787 | } |
788 | |
789 | // 3. Attempt to locate the DW_OP_entry_value expression in the set of |
790 | // available call site parameters. If found, evaluate the corresponding |
791 | // parameter in the context of the parent frame. |
792 | const uint32_t subexpr_len = opcodes.GetULEB128(&opcode_offset); |
793 | const void *subexpr_data = opcodes.GetData(&opcode_offset, subexpr_len); |
794 | if (!subexpr_data) { |
795 | 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("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: subexpr could not be read" ); } while (0); |
796 | return false; |
797 | } |
798 | |
799 | const CallSiteParameter *matched_param = nullptr; |
800 | for (const CallSiteParameter ¶m : call_edge->GetCallSiteParameters()) { |
801 | DataExtractor param_subexpr_extractor; |
802 | if (!param.LocationInCallee.GetExpressionData(param_subexpr_extractor)) |
803 | continue; |
804 | lldb::offset_t param_subexpr_offset = 0; |
805 | const void *param_subexpr_data = |
806 | param_subexpr_extractor.GetData(¶m_subexpr_offset, subexpr_len); |
807 | if (!param_subexpr_data || |
808 | param_subexpr_extractor.BytesLeft(param_subexpr_offset) != 0) |
809 | continue; |
810 | |
811 | // At this point, the DW_OP_entry_value sub-expression and the callee-side |
812 | // expression in the call site parameter are known to have the same length. |
813 | // Check whether they are equal. |
814 | // |
815 | // Note that an equality check is sufficient: the contents of the |
816 | // DW_OP_entry_value subexpression are only used to identify the right call |
817 | // site parameter in the parent, and do not require any special handling. |
818 | if (memcmp(subexpr_data, param_subexpr_data, subexpr_len) == 0) { |
819 | matched_param = ¶m; |
820 | break; |
821 | } |
822 | } |
823 | if (!matched_param) { |
824 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no matching call site param found" ); } while (0) |
825 | "Evaluate_DW_OP_entry_value: no matching call site param found")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no matching call site param found" ); } while (0); |
826 | return false; |
827 | } |
828 | |
829 | // TODO: Add support for DW_OP_push_object_address within a DW_OP_entry_value |
830 | // subexpresion whenever llvm does. |
831 | Value result; |
832 | const DWARFExpression ¶m_expr = matched_param->LocationInCaller; |
833 | if (!param_expr.Evaluate(&parent_exe_ctx, |
834 | parent_frame->GetRegisterContext().get(), |
835 | /*loclist_base_addr=*/LLDB_INVALID_ADDRESS0xffffffffffffffffULL, |
836 | /*initial_value_ptr=*/nullptr, |
837 | /*object_address_ptr=*/nullptr, result, error_ptr)) { |
838 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: call site param evaluation failed" ); } while (0) |
839 | "Evaluate_DW_OP_entry_value: call site param evaluation failed")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: call site param evaluation failed" ); } while (0); |
840 | return false; |
841 | } |
842 | |
843 | stack.push_back(result); |
844 | return true; |
845 | } |
846 | |
847 | bool DWARFExpression::Evaluate(ExecutionContextScope *exe_scope, |
848 | lldb::addr_t loclist_base_load_addr, |
849 | const Value *initial_value_ptr, |
850 | const Value *object_address_ptr, Value &result, |
851 | Status *error_ptr) const { |
852 | ExecutionContext exe_ctx(exe_scope); |
853 | return Evaluate(&exe_ctx, nullptr, loclist_base_load_addr, initial_value_ptr, |
854 | object_address_ptr, result, error_ptr); |
855 | } |
856 | |
857 | bool DWARFExpression::Evaluate(ExecutionContext *exe_ctx, |
858 | RegisterContext *reg_ctx, |
859 | lldb::addr_t func_load_addr, |
860 | const Value *initial_value_ptr, |
861 | const Value *object_address_ptr, Value &result, |
862 | Status *error_ptr) const { |
863 | ModuleSP module_sp = m_module_wp.lock(); |
864 | |
865 | if (IsLocationList()) { |
866 | addr_t pc; |
867 | StackFrame *frame = nullptr; |
868 | if (reg_ctx) |
869 | pc = reg_ctx->GetPC(); |
870 | else { |
871 | frame = exe_ctx->GetFramePtr(); |
872 | if (!frame) |
873 | return false; |
874 | RegisterContextSP reg_ctx_sp = frame->GetRegisterContext(); |
875 | if (!reg_ctx_sp) |
876 | return false; |
877 | pc = reg_ctx_sp->GetPC(); |
878 | } |
879 | |
880 | if (func_load_addr != LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
881 | if (pc == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
882 | if (error_ptr) |
883 | error_ptr->SetErrorString("Invalid PC in frame."); |
884 | return false; |
885 | } |
886 | |
887 | if (llvm::Optional<DataExtractor> expr = |
888 | GetLocationExpression(func_load_addr, pc)) { |
889 | return DWARFExpression::Evaluate( |
890 | exe_ctx, reg_ctx, module_sp, *expr, m_dwarf_cu, m_reg_kind, |
891 | initial_value_ptr, object_address_ptr, result, error_ptr); |
892 | } |
893 | } |
894 | if (error_ptr) |
895 | error_ptr->SetErrorString("variable not available"); |
896 | return false; |
897 | } |
898 | |
899 | // Not a location list, just a single expression. |
900 | return DWARFExpression::Evaluate(exe_ctx, reg_ctx, module_sp, m_data, |
901 | m_dwarf_cu, m_reg_kind, initial_value_ptr, |
902 | object_address_ptr, result, error_ptr); |
903 | } |
904 | |
905 | namespace { |
906 | /// The location description kinds described by the DWARF v5 |
907 | /// specification. Composite locations are handled out-of-band and |
908 | /// thus aren't part of the enum. |
909 | enum LocationDescriptionKind { |
910 | Empty, |
911 | Memory, |
912 | Register, |
913 | Implicit |
914 | /* Composite*/ |
915 | }; |
916 | /// Adjust value's ValueType according to the kind of location description. |
917 | void UpdateValueTypeFromLocationDescription(Log *log, const DWARFUnit *dwarf_cu, |
918 | LocationDescriptionKind kind, |
919 | Value *value = nullptr) { |
920 | // Note that this function is conflating DWARF expressions with |
921 | // DWARF location descriptions. Perhaps it would be better to define |
922 | // a wrapper for DWARFExpresssion::Eval() that deals with DWARF |
923 | // location descriptions (which consist of one or more DWARF |
924 | // expressions). But doing this would mean we'd also need factor the |
925 | // handling of DW_OP_(bit_)piece out of this function. |
926 | if (dwarf_cu && dwarf_cu->GetVersion() >= 4) { |
927 | const char *log_msg = "DWARF location description kind: %s"; |
928 | switch (kind) { |
929 | case Empty: |
930 | LLDB_LOGF(log, log_msg, "Empty")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Empty"); } while (0); |
931 | break; |
932 | case Memory: |
933 | LLDB_LOGF(log, log_msg, "Memory")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Memory"); } while (0); |
934 | if (value->GetValueType() == Value::ValueType::Scalar) |
935 | value->SetValueType(Value::ValueType::LoadAddress); |
936 | break; |
937 | case Register: |
938 | LLDB_LOGF(log, log_msg, "Register")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Register"); } while (0); |
939 | value->SetValueType(Value::ValueType::Scalar); |
940 | break; |
941 | case Implicit: |
942 | LLDB_LOGF(log, log_msg, "Implicit")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Implicit"); } while (0); |
943 | if (value->GetValueType() == Value::ValueType::LoadAddress) |
944 | value->SetValueType(Value::ValueType::Scalar); |
945 | break; |
946 | } |
947 | } |
948 | } |
949 | } // namespace |
950 | |
951 | bool DWARFExpression::Evaluate( |
952 | ExecutionContext *exe_ctx, RegisterContext *reg_ctx, |
953 | lldb::ModuleSP module_sp, const DataExtractor &opcodes, |
954 | const DWARFUnit *dwarf_cu, const lldb::RegisterKind reg_kind, |
955 | const Value *initial_value_ptr, const Value *object_address_ptr, |
956 | Value &result, Status *error_ptr) { |
957 | |
958 | if (opcodes.GetByteSize() == 0) { |
959 | if (error_ptr) |
960 | error_ptr->SetErrorString( |
961 | "no location, value may have been optimized out"); |
962 | return false; |
963 | } |
964 | std::vector<Value> stack; |
965 | |
966 | Process *process = nullptr; |
967 | StackFrame *frame = nullptr; |
968 | |
969 | if (exe_ctx) { |
970 | process = exe_ctx->GetProcessPtr(); |
971 | frame = exe_ctx->GetFramePtr(); |
972 | } |
973 | if (reg_ctx == nullptr && frame) |
974 | reg_ctx = frame->GetRegisterContext().get(); |
975 | |
976 | if (initial_value_ptr) |
977 | stack.push_back(*initial_value_ptr); |
978 | |
979 | lldb::offset_t offset = 0; |
980 | Value tmp; |
981 | uint32_t reg_num; |
982 | |
983 | /// Insertion point for evaluating multi-piece expression. |
984 | uint64_t op_piece_offset = 0; |
985 | Value pieces; // Used for DW_OP_piece |
986 | |
987 | Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8))); |
988 | // A generic type is "an integral type that has the size of an address and an |
989 | // unspecified signedness". For now, just use the signedness of the operand. |
990 | // TODO: Implement a real typed stack, and store the genericness of the value |
991 | // there. |
992 | auto to_generic = [&](auto v) { |
993 | bool is_signed = std::is_signed<decltype(v)>::value; |
994 | return Scalar(llvm::APSInt( |
995 | llvm::APInt(8 * opcodes.GetAddressByteSize(), v, is_signed), |
996 | !is_signed)); |
997 | }; |
998 | |
999 | // The default kind is a memory location. This is updated by any |
1000 | // operation that changes this, such as DW_OP_stack_value, and reset |
1001 | // by composition operations like DW_OP_piece. |
1002 | LocationDescriptionKind dwarf4_location_description_kind = Memory; |
1003 | |
1004 | while (opcodes.ValidOffset(offset)) { |
1005 | const lldb::offset_t op_offset = offset; |
1006 | const uint8_t op = opcodes.GetU8(&offset); |
1007 | |
1008 | if (log && log->GetVerbose()) { |
1009 | size_t count = stack.size(); |
1010 | 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 %" "llu" " values:", (uint64_t)count); } while (0) |
1011 | (uint64_t)count)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack before operation has %" "llu" " values:", (uint64_t)count); } while (0); |
1012 | for (size_t i = 0; i < count; ++i) { |
1013 | StreamString new_value; |
1014 | new_value.Printf("[%" PRIu64"llu" "]", (uint64_t)i); |
1015 | stack[i].Dump(&new_value); |
1016 | 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); |
1017 | } |
1018 | 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" "llx" ": %s", op_offset, DW_OP_value_to_name (op)); } while (0) |
1019 | DW_OP_value_to_name(op))do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("0x%8.8" "llx" ": %s", op_offset, DW_OP_value_to_name (op)); } while (0); |
1020 | } |
1021 | |
1022 | switch (op) { |
1023 | // The DW_OP_addr operation has a single operand that encodes a machine |
1024 | // address and whose size is the size of an address on the target machine. |
1025 | case DW_OP_addr: |
1026 | stack.push_back(Scalar(opcodes.GetAddress(&offset))); |
1027 | stack.back().SetValueType(Value::ValueType::FileAddress); |
1028 | // Convert the file address to a load address, so subsequent |
1029 | // DWARF operators can operate on it. |
1030 | if (frame) |
1031 | stack.back().ConvertToLoadAddress(module_sp.get(), |
1032 | frame->CalculateTarget().get()); |
1033 | break; |
1034 | |
1035 | // The DW_OP_addr_sect_offset4 is used for any location expressions in |
1036 | // shared libraries that have a location like: |
1037 | // DW_OP_addr(0x1000) |
1038 | // If this address resides in a shared library, then this virtual address |
1039 | // won't make sense when it is evaluated in the context of a running |
1040 | // process where shared libraries have been slid. To account for this, this |
1041 | // new address type where we can store the section pointer and a 4 byte |
1042 | // offset. |
1043 | // case DW_OP_addr_sect_offset4: |
1044 | // { |
1045 | // result_type = eResultTypeFileAddress; |
1046 | // lldb::Section *sect = (lldb::Section |
1047 | // *)opcodes.GetMaxU64(&offset, sizeof(void *)); |
1048 | // lldb::addr_t sect_offset = opcodes.GetU32(&offset); |
1049 | // |
1050 | // Address so_addr (sect, sect_offset); |
1051 | // lldb::addr_t load_addr = so_addr.GetLoadAddress(); |
1052 | // if (load_addr != LLDB_INVALID_ADDRESS) |
1053 | // { |
1054 | // // We successfully resolve a file address to a load |
1055 | // // address. |
1056 | // stack.push_back(load_addr); |
1057 | // break; |
1058 | // } |
1059 | // else |
1060 | // { |
1061 | // // We were able |
1062 | // if (error_ptr) |
1063 | // error_ptr->SetErrorStringWithFormat ("Section %s in |
1064 | // %s is not currently loaded.\n", |
1065 | // sect->GetName().AsCString(), |
1066 | // sect->GetModule()->GetFileSpec().GetFilename().AsCString()); |
1067 | // return false; |
1068 | // } |
1069 | // } |
1070 | // break; |
1071 | |
1072 | // OPCODE: DW_OP_deref |
1073 | // OPERANDS: none |
1074 | // DESCRIPTION: Pops the top stack entry and treats it as an address. |
1075 | // The value retrieved from that address is pushed. The size of the data |
1076 | // retrieved from the dereferenced address is the size of an address on the |
1077 | // target machine. |
1078 | case DW_OP_deref: { |
1079 | if (stack.empty()) { |
1080 | if (error_ptr) |
1081 | error_ptr->SetErrorString("Expression stack empty for DW_OP_deref."); |
1082 | return false; |
1083 | } |
1084 | Value::ValueType value_type = stack.back().GetValueType(); |
1085 | switch (value_type) { |
1086 | case Value::ValueType::HostAddress: { |
1087 | void *src = (void *)stack.back().GetScalar().ULongLong(); |
1088 | intptr_t ptr; |
1089 | ::memcpy(&ptr, src, sizeof(void *)); |
1090 | stack.back().GetScalar() = ptr; |
1091 | stack.back().ClearContext(); |
1092 | } break; |
1093 | case Value::ValueType::FileAddress: { |
1094 | auto file_addr = stack.back().GetScalar().ULongLong( |
1095 | LLDB_INVALID_ADDRESS0xffffffffffffffffULL); |
1096 | if (!module_sp) { |
1097 | if (error_ptr) |
1098 | error_ptr->SetErrorString( |
1099 | "need module to resolve file address for DW_OP_deref"); |
1100 | return false; |
1101 | } |
1102 | Address so_addr; |
1103 | if (!module_sp->ResolveFileAddress(file_addr, so_addr)) { |
1104 | if (error_ptr) |
1105 | error_ptr->SetErrorString( |
1106 | "failed to resolve file address in module"); |
1107 | return false; |
1108 | } |
1109 | addr_t load_Addr = so_addr.GetLoadAddress(exe_ctx->GetTargetPtr()); |
1110 | if (load_Addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
1111 | if (error_ptr) |
1112 | error_ptr->SetErrorString("failed to resolve load address"); |
1113 | return false; |
1114 | } |
1115 | stack.back().GetScalar() = load_Addr; |
1116 | // Fall through to load address promotion code below. |
1117 | } LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
1118 | case Value::ValueType::Scalar: |
1119 | // Promote Scalar to LoadAddress and fall through. |
1120 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
1121 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
1122 | case Value::ValueType::LoadAddress: |
1123 | if (exe_ctx) { |
1124 | if (process) { |
1125 | lldb::addr_t pointer_addr = |
1126 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS0xffffffffffffffffULL); |
1127 | Status error; |
1128 | lldb::addr_t pointer_value = |
1129 | process->ReadPointerFromMemory(pointer_addr, error); |
1130 | if (pointer_value != LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
1131 | if (ABISP abi_sp = process->GetABI()) |
1132 | pointer_value = abi_sp->FixCodeAddress(pointer_value); |
1133 | stack.back().GetScalar() = pointer_value; |
1134 | stack.back().ClearContext(); |
1135 | } else { |
1136 | if (error_ptr) |
1137 | error_ptr->SetErrorStringWithFormat( |
1138 | "Failed to dereference pointer from 0x%" PRIx64"llx" |
1139 | " for DW_OP_deref: %s\n", |
1140 | pointer_addr, error.AsCString()); |
1141 | return false; |
1142 | } |
1143 | } else { |
1144 | if (error_ptr) |
1145 | error_ptr->SetErrorString("NULL process for DW_OP_deref.\n"); |
1146 | return false; |
1147 | } |
1148 | } else { |
1149 | if (error_ptr) |
1150 | error_ptr->SetErrorString( |
1151 | "NULL execution context for DW_OP_deref.\n"); |
1152 | return false; |
1153 | } |
1154 | break; |
1155 | |
1156 | case Value::ValueType::Invalid: |
1157 | if (error_ptr) |
1158 | error_ptr->SetErrorString("Invalid value type for DW_OP_deref.\n"); |
1159 | return false; |
1160 | } |
1161 | |
1162 | } break; |
1163 | |
1164 | // OPCODE: DW_OP_deref_size |
1165 | // OPERANDS: 1 |
1166 | // 1 - uint8_t that specifies the size of the data to dereference. |
1167 | // DESCRIPTION: Behaves like the DW_OP_deref operation: it pops the top |
1168 | // stack entry and treats it as an address. The value retrieved from that |
1169 | // address is pushed. In the DW_OP_deref_size operation, however, the size |
1170 | // in bytes of the data retrieved from the dereferenced address is |
1171 | // specified by the single operand. This operand is a 1-byte unsigned |
1172 | // integral constant whose value may not be larger than the size of an |
1173 | // address on the target machine. The data retrieved is zero extended to |
1174 | // the size of an address on the target machine before being pushed on the |
1175 | // expression stack. |
1176 | case DW_OP_deref_size: { |
1177 | if (stack.empty()) { |
1178 | if (error_ptr) |
1179 | error_ptr->SetErrorString( |
1180 | "Expression stack empty for DW_OP_deref_size."); |
1181 | return false; |
1182 | } |
1183 | uint8_t size = opcodes.GetU8(&offset); |
1184 | Value::ValueType value_type = stack.back().GetValueType(); |
1185 | switch (value_type) { |
1186 | case Value::ValueType::HostAddress: { |
1187 | void *src = (void *)stack.back().GetScalar().ULongLong(); |
1188 | intptr_t ptr; |
1189 | ::memcpy(&ptr, src, sizeof(void *)); |
1190 | // I can't decide whether the size operand should apply to the bytes in |
1191 | // their |
1192 | // lldb-host endianness or the target endianness.. I doubt this'll ever |
1193 | // come up but I'll opt for assuming big endian regardless. |
1194 | switch (size) { |
1195 | case 1: |
1196 | ptr = ptr & 0xff; |
1197 | break; |
1198 | case 2: |
1199 | ptr = ptr & 0xffff; |
1200 | break; |
1201 | case 3: |
1202 | ptr = ptr & 0xffffff; |
1203 | break; |
1204 | case 4: |
1205 | ptr = ptr & 0xffffffff; |
1206 | break; |
1207 | // the casts are added to work around the case where intptr_t is a 32 |
1208 | // bit quantity; |
1209 | // presumably we won't hit the 5..7 cases if (void*) is 32-bits in this |
1210 | // program. |
1211 | case 5: |
1212 | ptr = (intptr_t)ptr & 0xffffffffffULL; |
1213 | break; |
1214 | case 6: |
1215 | ptr = (intptr_t)ptr & 0xffffffffffffULL; |
1216 | break; |
1217 | case 7: |
1218 | ptr = (intptr_t)ptr & 0xffffffffffffffULL; |
1219 | break; |
1220 | default: |
1221 | break; |
1222 | } |
1223 | stack.back().GetScalar() = ptr; |
1224 | stack.back().ClearContext(); |
1225 | } break; |
1226 | case Value::ValueType::Scalar: |
1227 | case Value::ValueType::LoadAddress: |
1228 | if (exe_ctx) { |
1229 | if (process) { |
1230 | lldb::addr_t pointer_addr = |
1231 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS0xffffffffffffffffULL); |
1232 | uint8_t addr_bytes[sizeof(lldb::addr_t)]; |
1233 | Status error; |
1234 | if (process->ReadMemory(pointer_addr, &addr_bytes, size, error) == |
1235 | size) { |
1236 | DataExtractor addr_data(addr_bytes, sizeof(addr_bytes), |
1237 | process->GetByteOrder(), size); |
1238 | lldb::offset_t addr_data_offset = 0; |
1239 | switch (size) { |
1240 | case 1: |
1241 | stack.back().GetScalar() = addr_data.GetU8(&addr_data_offset); |
1242 | break; |
1243 | case 2: |
1244 | stack.back().GetScalar() = addr_data.GetU16(&addr_data_offset); |
1245 | break; |
1246 | case 4: |
1247 | stack.back().GetScalar() = addr_data.GetU32(&addr_data_offset); |
1248 | break; |
1249 | case 8: |
1250 | stack.back().GetScalar() = addr_data.GetU64(&addr_data_offset); |
1251 | break; |
1252 | default: |
1253 | stack.back().GetScalar() = |
1254 | addr_data.GetAddress(&addr_data_offset); |
1255 | } |
1256 | stack.back().ClearContext(); |
1257 | } else { |
1258 | if (error_ptr) |
1259 | error_ptr->SetErrorStringWithFormat( |
1260 | "Failed to dereference pointer from 0x%" PRIx64"llx" |
1261 | " for DW_OP_deref: %s\n", |
1262 | pointer_addr, error.AsCString()); |
1263 | return false; |
1264 | } |
1265 | } else { |
1266 | if (error_ptr) |
1267 | error_ptr->SetErrorString("NULL process for DW_OP_deref_size.\n"); |
1268 | return false; |
1269 | } |
1270 | } else { |
1271 | if (error_ptr) |
1272 | error_ptr->SetErrorString( |
1273 | "NULL execution context for DW_OP_deref_size.\n"); |
1274 | return false; |
1275 | } |
1276 | break; |
1277 | |
1278 | case Value::ValueType::FileAddress: |
1279 | case Value::ValueType::Invalid: |
1280 | if (error_ptr) |
1281 | error_ptr->SetErrorString("Invalid value for DW_OP_deref_size.\n"); |
1282 | return false; |
1283 | } |
1284 | |
1285 | } break; |
1286 | |
1287 | // OPCODE: DW_OP_xderef_size |
1288 | // OPERANDS: 1 |
1289 | // 1 - uint8_t that specifies the size of the data to dereference. |
1290 | // DESCRIPTION: Behaves like the DW_OP_xderef operation: the entry at |
1291 | // the top of the stack is treated as an address. The second stack entry is |
1292 | // treated as an "address space identifier" for those architectures that |
1293 | // support multiple address spaces. The top two stack elements are popped, |
1294 | // a data item is retrieved through an implementation-defined address |
1295 | // calculation and pushed as the new stack top. In the DW_OP_xderef_size |
1296 | // operation, however, the size in bytes of the data retrieved from the |
1297 | // dereferenced address is specified by the single operand. This operand is |
1298 | // a 1-byte unsigned integral constant whose value may not be larger than |
1299 | // the size of an address on the target machine. The data retrieved is zero |
1300 | // extended to the size of an address on the target machine before being |
1301 | // pushed on the expression stack. |
1302 | case DW_OP_xderef_size: |
1303 | if (error_ptr) |
1304 | error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef_size."); |
1305 | return false; |
1306 | // OPCODE: DW_OP_xderef |
1307 | // OPERANDS: none |
1308 | // DESCRIPTION: Provides an extended dereference mechanism. The entry at |
1309 | // the top of the stack is treated as an address. The second stack entry is |
1310 | // treated as an "address space identifier" for those architectures that |
1311 | // support multiple address spaces. The top two stack elements are popped, |
1312 | // a data item is retrieved through an implementation-defined address |
1313 | // calculation and pushed as the new stack top. The size of the data |
1314 | // retrieved from the dereferenced address is the size of an address on the |
1315 | // target machine. |
1316 | case DW_OP_xderef: |
1317 | if (error_ptr) |
1318 | error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef."); |
1319 | return false; |
1320 | |
1321 | // All DW_OP_constXXX opcodes have a single operand as noted below: |
1322 | // |
1323 | // Opcode Operand 1 |
1324 | // DW_OP_const1u 1-byte unsigned integer constant |
1325 | // DW_OP_const1s 1-byte signed integer constant |
1326 | // DW_OP_const2u 2-byte unsigned integer constant |
1327 | // DW_OP_const2s 2-byte signed integer constant |
1328 | // DW_OP_const4u 4-byte unsigned integer constant |
1329 | // DW_OP_const4s 4-byte signed integer constant |
1330 | // DW_OP_const8u 8-byte unsigned integer constant |
1331 | // DW_OP_const8s 8-byte signed integer constant |
1332 | // DW_OP_constu unsigned LEB128 integer constant |
1333 | // DW_OP_consts signed LEB128 integer constant |
1334 | case DW_OP_const1u: |
1335 | stack.push_back(to_generic(opcodes.GetU8(&offset))); |
1336 | break; |
1337 | case DW_OP_const1s: |
1338 | stack.push_back(to_generic((int8_t)opcodes.GetU8(&offset))); |
1339 | break; |
1340 | case DW_OP_const2u: |
1341 | stack.push_back(to_generic(opcodes.GetU16(&offset))); |
1342 | break; |
1343 | case DW_OP_const2s: |
1344 | stack.push_back(to_generic((int16_t)opcodes.GetU16(&offset))); |
1345 | break; |
1346 | case DW_OP_const4u: |
1347 | stack.push_back(to_generic(opcodes.GetU32(&offset))); |
1348 | break; |
1349 | case DW_OP_const4s: |
1350 | stack.push_back(to_generic((int32_t)opcodes.GetU32(&offset))); |
1351 | break; |
1352 | case DW_OP_const8u: |
1353 | stack.push_back(to_generic(opcodes.GetU64(&offset))); |
1354 | break; |
1355 | case DW_OP_const8s: |
1356 | stack.push_back(to_generic((int64_t)opcodes.GetU64(&offset))); |
1357 | break; |
1358 | // These should also use to_generic, but we can't do that due to a |
1359 | // producer-side bug in llvm. See llvm.org/pr48087. |
1360 | case DW_OP_constu: |
1361 | stack.push_back(Scalar(opcodes.GetULEB128(&offset))); |
1362 | break; |
1363 | case DW_OP_consts: |
1364 | stack.push_back(Scalar(opcodes.GetSLEB128(&offset))); |
1365 | break; |
1366 | |
1367 | // OPCODE: DW_OP_dup |
1368 | // OPERANDS: none |
1369 | // DESCRIPTION: duplicates the value at the top of the stack |
1370 | case DW_OP_dup: |
1371 | if (stack.empty()) { |
1372 | if (error_ptr) |
1373 | error_ptr->SetErrorString("Expression stack empty for DW_OP_dup."); |
1374 | return false; |
1375 | } else |
1376 | stack.push_back(stack.back()); |
1377 | break; |
1378 | |
1379 | // OPCODE: DW_OP_drop |
1380 | // OPERANDS: none |
1381 | // DESCRIPTION: pops the value at the top of the stack |
1382 | case DW_OP_drop: |
1383 | if (stack.empty()) { |
1384 | if (error_ptr) |
1385 | error_ptr->SetErrorString("Expression stack empty for DW_OP_drop."); |
1386 | return false; |
1387 | } else |
1388 | stack.pop_back(); |
1389 | break; |
1390 | |
1391 | // OPCODE: DW_OP_over |
1392 | // OPERANDS: none |
1393 | // DESCRIPTION: Duplicates the entry currently second in the stack at |
1394 | // the top of the stack. |
1395 | case DW_OP_over: |
1396 | if (stack.size() < 2) { |
1397 | if (error_ptr) |
1398 | error_ptr->SetErrorString( |
1399 | "Expression stack needs at least 2 items for DW_OP_over."); |
1400 | return false; |
1401 | } else |
1402 | stack.push_back(stack[stack.size() - 2]); |
1403 | break; |
1404 | |
1405 | // OPCODE: DW_OP_pick |
1406 | // OPERANDS: uint8_t index into the current stack |
1407 | // DESCRIPTION: The stack entry with the specified index (0 through 255, |
1408 | // inclusive) is pushed on the stack |
1409 | case DW_OP_pick: { |
1410 | uint8_t pick_idx = opcodes.GetU8(&offset); |
1411 | if (pick_idx < stack.size()) |
1412 | stack.push_back(stack[stack.size() - 1 - pick_idx]); |
1413 | else { |
1414 | if (error_ptr) |
1415 | error_ptr->SetErrorStringWithFormat( |
1416 | "Index %u out of range for DW_OP_pick.\n", pick_idx); |
1417 | return false; |
1418 | } |
1419 | } break; |
1420 | |
1421 | // OPCODE: DW_OP_swap |
1422 | // OPERANDS: none |
1423 | // DESCRIPTION: swaps the top two stack entries. The entry at the top |
1424 | // of the stack becomes the second stack entry, and the second entry |
1425 | // becomes the top of the stack |
1426 | case DW_OP_swap: |
1427 | if (stack.size() < 2) { |
1428 | if (error_ptr) |
1429 | error_ptr->SetErrorString( |
1430 | "Expression stack needs at least 2 items for DW_OP_swap."); |
1431 | return false; |
1432 | } else { |
1433 | tmp = stack.back(); |
1434 | stack.back() = stack[stack.size() - 2]; |
1435 | stack[stack.size() - 2] = tmp; |
1436 | } |
1437 | break; |
1438 | |
1439 | // OPCODE: DW_OP_rot |
1440 | // OPERANDS: none |
1441 | // DESCRIPTION: Rotates the first three stack entries. The entry at |
1442 | // the top of the stack becomes the third stack entry, the second entry |
1443 | // becomes the top of the stack, and the third entry becomes the second |
1444 | // entry. |
1445 | case DW_OP_rot: |
1446 | if (stack.size() < 3) { |
1447 | if (error_ptr) |
1448 | error_ptr->SetErrorString( |
1449 | "Expression stack needs at least 3 items for DW_OP_rot."); |
1450 | return false; |
1451 | } else { |
1452 | size_t last_idx = stack.size() - 1; |
1453 | Value old_top = stack[last_idx]; |
1454 | stack[last_idx] = stack[last_idx - 1]; |
1455 | stack[last_idx - 1] = stack[last_idx - 2]; |
1456 | stack[last_idx - 2] = old_top; |
1457 | } |
1458 | break; |
1459 | |
1460 | // OPCODE: DW_OP_abs |
1461 | // OPERANDS: none |
1462 | // DESCRIPTION: pops the top stack entry, interprets it as a signed |
1463 | // value and pushes its absolute value. If the absolute value can not be |
1464 | // represented, the result is undefined. |
1465 | case DW_OP_abs: |
1466 | if (stack.empty()) { |
1467 | if (error_ptr) |
1468 | error_ptr->SetErrorString( |
1469 | "Expression stack needs at least 1 item for DW_OP_abs."); |
1470 | return false; |
1471 | } else if (!stack.back().ResolveValue(exe_ctx).AbsoluteValue()) { |
1472 | if (error_ptr) |
1473 | error_ptr->SetErrorString( |
1474 | "Failed to take the absolute value of the first stack item."); |
1475 | return false; |
1476 | } |
1477 | break; |
1478 | |
1479 | // OPCODE: DW_OP_and |
1480 | // OPERANDS: none |
1481 | // DESCRIPTION: pops the top two stack values, performs a bitwise and |
1482 | // operation on the two, and pushes the result. |
1483 | case DW_OP_and: |
1484 | if (stack.size() < 2) { |
1485 | if (error_ptr) |
1486 | error_ptr->SetErrorString( |
1487 | "Expression stack needs at least 2 items for DW_OP_and."); |
1488 | return false; |
1489 | } else { |
1490 | tmp = stack.back(); |
1491 | stack.pop_back(); |
1492 | stack.back().ResolveValue(exe_ctx) = |
1493 | stack.back().ResolveValue(exe_ctx) & tmp.ResolveValue(exe_ctx); |
1494 | } |
1495 | break; |
1496 | |
1497 | // OPCODE: DW_OP_div |
1498 | // OPERANDS: none |
1499 | // DESCRIPTION: pops the top two stack values, divides the former second |
1500 | // entry by the former top of the stack using signed division, and pushes |
1501 | // the result. |
1502 | case DW_OP_div: |
1503 | if (stack.size() < 2) { |
1504 | if (error_ptr) |
1505 | error_ptr->SetErrorString( |
1506 | "Expression stack needs at least 2 items for DW_OP_div."); |
1507 | return false; |
1508 | } else { |
1509 | tmp = stack.back(); |
1510 | if (tmp.ResolveValue(exe_ctx).IsZero()) { |
1511 | if (error_ptr) |
1512 | error_ptr->SetErrorString("Divide by zero."); |
1513 | return false; |
1514 | } else { |
1515 | stack.pop_back(); |
1516 | stack.back() = |
1517 | stack.back().ResolveValue(exe_ctx) / tmp.ResolveValue(exe_ctx); |
1518 | if (!stack.back().ResolveValue(exe_ctx).IsValid()) { |
1519 | if (error_ptr) |
1520 | error_ptr->SetErrorString("Divide failed."); |
1521 | return false; |
1522 | } |
1523 | } |
1524 | } |
1525 | break; |
1526 | |
1527 | // OPCODE: DW_OP_minus |
1528 | // OPERANDS: none |
1529 | // DESCRIPTION: pops the top two stack values, subtracts the former top |
1530 | // of the stack from the former second entry, and pushes the result. |
1531 | case DW_OP_minus: |
1532 | if (stack.size() < 2) { |
1533 | if (error_ptr) |
1534 | error_ptr->SetErrorString( |
1535 | "Expression stack needs at least 2 items for DW_OP_minus."); |
1536 | return false; |
1537 | } else { |
1538 | tmp = stack.back(); |
1539 | stack.pop_back(); |
1540 | stack.back().ResolveValue(exe_ctx) = |
1541 | stack.back().ResolveValue(exe_ctx) - tmp.ResolveValue(exe_ctx); |
1542 | } |
1543 | break; |
1544 | |
1545 | // OPCODE: DW_OP_mod |
1546 | // OPERANDS: none |
1547 | // DESCRIPTION: pops the top two stack values and pushes the result of |
1548 | // the calculation: former second stack entry modulo the former top of the |
1549 | // stack. |
1550 | case DW_OP_mod: |
1551 | if (stack.size() < 2) { |
1552 | if (error_ptr) |
1553 | error_ptr->SetErrorString( |
1554 | "Expression stack needs at least 2 items for DW_OP_mod."); |
1555 | return false; |
1556 | } else { |
1557 | tmp = stack.back(); |
1558 | stack.pop_back(); |
1559 | stack.back().ResolveValue(exe_ctx) = |
1560 | stack.back().ResolveValue(exe_ctx) % tmp.ResolveValue(exe_ctx); |
1561 | } |
1562 | break; |
1563 | |
1564 | // OPCODE: DW_OP_mul |
1565 | // OPERANDS: none |
1566 | // DESCRIPTION: pops the top two stack entries, multiplies them |
1567 | // together, and pushes the result. |
1568 | case DW_OP_mul: |
1569 | if (stack.size() < 2) { |
1570 | if (error_ptr) |
1571 | error_ptr->SetErrorString( |
1572 | "Expression stack needs at least 2 items for DW_OP_mul."); |
1573 | return false; |
1574 | } else { |
1575 | tmp = stack.back(); |
1576 | stack.pop_back(); |
1577 | stack.back().ResolveValue(exe_ctx) = |
1578 | stack.back().ResolveValue(exe_ctx) * tmp.ResolveValue(exe_ctx); |
1579 | } |
1580 | break; |
1581 | |
1582 | // OPCODE: DW_OP_neg |
1583 | // OPERANDS: none |
1584 | // DESCRIPTION: pops the top stack entry, and pushes its negation. |
1585 | case DW_OP_neg: |
1586 | if (stack.empty()) { |
1587 | if (error_ptr) |
1588 | error_ptr->SetErrorString( |
1589 | "Expression stack needs at least 1 item for DW_OP_neg."); |
1590 | return false; |
1591 | } else { |
1592 | if (!stack.back().ResolveValue(exe_ctx).UnaryNegate()) { |
1593 | if (error_ptr) |
1594 | error_ptr->SetErrorString("Unary negate failed."); |
1595 | return false; |
1596 | } |
1597 | } |
1598 | break; |
1599 | |
1600 | // OPCODE: DW_OP_not |
1601 | // OPERANDS: none |
1602 | // DESCRIPTION: pops the top stack entry, and pushes its bitwise |
1603 | // complement |
1604 | case DW_OP_not: |
1605 | if (stack.empty()) { |
1606 | if (error_ptr) |
1607 | error_ptr->SetErrorString( |
1608 | "Expression stack needs at least 1 item for DW_OP_not."); |
1609 | return false; |
1610 | } else { |
1611 | if (!stack.back().ResolveValue(exe_ctx).OnesComplement()) { |
1612 | if (error_ptr) |
1613 | error_ptr->SetErrorString("Logical NOT failed."); |
1614 | return false; |
1615 | } |
1616 | } |
1617 | break; |
1618 | |
1619 | // OPCODE: DW_OP_or |
1620 | // OPERANDS: none |
1621 | // DESCRIPTION: pops the top two stack entries, performs a bitwise or |
1622 | // operation on the two, and pushes the result. |
1623 | case DW_OP_or: |
1624 | if (stack.size() < 2) { |
1625 | if (error_ptr) |
1626 | error_ptr->SetErrorString( |
1627 | "Expression stack needs at least 2 items for DW_OP_or."); |
1628 | return false; |
1629 | } else { |
1630 | tmp = stack.back(); |
1631 | stack.pop_back(); |
1632 | stack.back().ResolveValue(exe_ctx) = |
1633 | stack.back().ResolveValue(exe_ctx) | tmp.ResolveValue(exe_ctx); |
1634 | } |
1635 | break; |
1636 | |
1637 | // OPCODE: DW_OP_plus |
1638 | // OPERANDS: none |
1639 | // DESCRIPTION: pops the top two stack entries, adds them together, and |
1640 | // pushes the result. |
1641 | case DW_OP_plus: |
1642 | if (stack.size() < 2) { |
1643 | if (error_ptr) |
1644 | error_ptr->SetErrorString( |
1645 | "Expression stack needs at least 2 items for DW_OP_plus."); |
1646 | return false; |
1647 | } else { |
1648 | tmp = stack.back(); |
1649 | stack.pop_back(); |
1650 | stack.back().GetScalar() += tmp.GetScalar(); |
1651 | } |
1652 | break; |
1653 | |
1654 | // OPCODE: DW_OP_plus_uconst |
1655 | // OPERANDS: none |
1656 | // DESCRIPTION: pops the top stack entry, adds it to the unsigned LEB128 |
1657 | // constant operand and pushes the result. |
1658 | case DW_OP_plus_uconst: |
1659 | if (stack.empty()) { |
1660 | if (error_ptr) |
1661 | error_ptr->SetErrorString( |
1662 | "Expression stack needs at least 1 item for DW_OP_plus_uconst."); |
1663 | return false; |
1664 | } else { |
1665 | const uint64_t uconst_value = opcodes.GetULEB128(&offset); |
1666 | // Implicit conversion from a UINT to a Scalar... |
1667 | stack.back().GetScalar() += uconst_value; |
1668 | if (!stack.back().GetScalar().IsValid()) { |
1669 | if (error_ptr) |
1670 | error_ptr->SetErrorString("DW_OP_plus_uconst failed."); |
1671 | return false; |
1672 | } |
1673 | } |
1674 | break; |
1675 | |
1676 | // OPCODE: DW_OP_shl |
1677 | // OPERANDS: none |
1678 | // DESCRIPTION: pops the top two stack entries, shifts the former |
1679 | // second entry left by the number of bits specified by the former top of |
1680 | // the stack, and pushes the result. |
1681 | case DW_OP_shl: |
1682 | if (stack.size() < 2) { |
1683 | if (error_ptr) |
1684 | error_ptr->SetErrorString( |
1685 | "Expression stack needs at least 2 items for DW_OP_shl."); |
1686 | return false; |
1687 | } else { |
1688 | tmp = stack.back(); |
1689 | stack.pop_back(); |
1690 | stack.back().ResolveValue(exe_ctx) <<= tmp.ResolveValue(exe_ctx); |
1691 | } |
1692 | break; |
1693 | |
1694 | // OPCODE: DW_OP_shr |
1695 | // OPERANDS: none |
1696 | // DESCRIPTION: pops the top two stack entries, shifts the former second |
1697 | // entry right logically (filling with zero bits) by the number of bits |
1698 | // specified by the former top of the stack, and pushes the result. |
1699 | case DW_OP_shr: |
1700 | if (stack.size() < 2) { |
1701 | if (error_ptr) |
1702 | error_ptr->SetErrorString( |
1703 | "Expression stack needs at least 2 items for DW_OP_shr."); |
1704 | return false; |
1705 | } else { |
1706 | tmp = stack.back(); |
1707 | stack.pop_back(); |
1708 | if (!stack.back().ResolveValue(exe_ctx).ShiftRightLogical( |
1709 | tmp.ResolveValue(exe_ctx))) { |
1710 | if (error_ptr) |
1711 | error_ptr->SetErrorString("DW_OP_shr failed."); |
1712 | return false; |
1713 | } |
1714 | } |
1715 | break; |
1716 | |
1717 | // OPCODE: DW_OP_shra |
1718 | // OPERANDS: none |
1719 | // DESCRIPTION: pops the top two stack entries, shifts the former second |
1720 | // entry right arithmetically (divide the magnitude by 2, keep the same |
1721 | // sign for the result) by the number of bits specified by the former top |
1722 | // of the stack, and pushes the result. |
1723 | case DW_OP_shra: |
1724 | if (stack.size() < 2) { |
1725 | if (error_ptr) |
1726 | error_ptr->SetErrorString( |
1727 | "Expression stack needs at least 2 items for DW_OP_shra."); |
1728 | return false; |
1729 | } else { |
1730 | tmp = stack.back(); |
1731 | stack.pop_back(); |
1732 | stack.back().ResolveValue(exe_ctx) >>= tmp.ResolveValue(exe_ctx); |
1733 | } |
1734 | break; |
1735 | |
1736 | // OPCODE: DW_OP_xor |
1737 | // OPERANDS: none |
1738 | // DESCRIPTION: pops the top two stack entries, performs the bitwise |
1739 | // exclusive-or operation on the two, and pushes the result. |
1740 | case DW_OP_xor: |
1741 | if (stack.size() < 2) { |
1742 | if (error_ptr) |
1743 | error_ptr->SetErrorString( |
1744 | "Expression stack needs at least 2 items for DW_OP_xor."); |
1745 | return false; |
1746 | } else { |
1747 | tmp = stack.back(); |
1748 | stack.pop_back(); |
1749 | stack.back().ResolveValue(exe_ctx) = |
1750 | stack.back().ResolveValue(exe_ctx) ^ tmp.ResolveValue(exe_ctx); |
1751 | } |
1752 | break; |
1753 | |
1754 | // OPCODE: DW_OP_skip |
1755 | // OPERANDS: int16_t |
1756 | // DESCRIPTION: An unconditional branch. Its single operand is a 2-byte |
1757 | // signed integer constant. The 2-byte constant is the number of bytes of |
1758 | // the DWARF expression to skip forward or backward from the current |
1759 | // operation, beginning after the 2-byte constant. |
1760 | case DW_OP_skip: { |
1761 | int16_t skip_offset = (int16_t)opcodes.GetU16(&offset); |
1762 | lldb::offset_t new_offset = offset + skip_offset; |
1763 | if (opcodes.ValidOffset(new_offset)) |
1764 | offset = new_offset; |
1765 | else { |
1766 | if (error_ptr) |
1767 | error_ptr->SetErrorString("Invalid opcode offset in DW_OP_skip."); |
1768 | return false; |
1769 | } |
1770 | } break; |
1771 | |
1772 | // OPCODE: DW_OP_bra |
1773 | // OPERANDS: int16_t |
1774 | // DESCRIPTION: A conditional branch. Its single operand is a 2-byte |
1775 | // signed integer constant. This operation pops the top of stack. If the |
1776 | // value popped is not the constant 0, the 2-byte constant operand is the |
1777 | // number of bytes of the DWARF expression to skip forward or backward from |
1778 | // the current operation, beginning after the 2-byte constant. |
1779 | case DW_OP_bra: |
1780 | if (stack.empty()) { |
1781 | if (error_ptr) |
1782 | error_ptr->SetErrorString( |
1783 | "Expression stack needs at least 1 item for DW_OP_bra."); |
1784 | return false; |
1785 | } else { |
1786 | tmp = stack.back(); |
1787 | stack.pop_back(); |
1788 | int16_t bra_offset = (int16_t)opcodes.GetU16(&offset); |
1789 | Scalar zero(0); |
1790 | if (tmp.ResolveValue(exe_ctx) != zero) { |
1791 | lldb::offset_t new_offset = offset + bra_offset; |
1792 | if (opcodes.ValidOffset(new_offset)) |
1793 | offset = new_offset; |
1794 | else { |
1795 | if (error_ptr) |
1796 | error_ptr->SetErrorString("Invalid opcode offset in DW_OP_bra."); |
1797 | return false; |
1798 | } |
1799 | } |
1800 | } |
1801 | break; |
1802 | |
1803 | // OPCODE: DW_OP_eq |
1804 | // OPERANDS: none |
1805 | // DESCRIPTION: pops the top two stack values, compares using the |
1806 | // equals (==) operator. |
1807 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1808 | // of the operation is true or the constant value 0 if the result of the |
1809 | // operation is false. |
1810 | case DW_OP_eq: |
1811 | if (stack.size() < 2) { |
1812 | if (error_ptr) |
1813 | error_ptr->SetErrorString( |
1814 | "Expression stack needs at least 2 items for DW_OP_eq."); |
1815 | return false; |
1816 | } else { |
1817 | tmp = stack.back(); |
1818 | stack.pop_back(); |
1819 | stack.back().ResolveValue(exe_ctx) = |
1820 | stack.back().ResolveValue(exe_ctx) == tmp.ResolveValue(exe_ctx); |
1821 | } |
1822 | break; |
1823 | |
1824 | // OPCODE: DW_OP_ge |
1825 | // OPERANDS: none |
1826 | // DESCRIPTION: pops the top two stack values, compares using the |
1827 | // greater than or equal to (>=) operator. |
1828 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1829 | // of the operation is true or the constant value 0 if the result of the |
1830 | // operation is false. |
1831 | case DW_OP_ge: |
1832 | if (stack.size() < 2) { |
1833 | if (error_ptr) |
1834 | error_ptr->SetErrorString( |
1835 | "Expression stack needs at least 2 items for DW_OP_ge."); |
1836 | return false; |
1837 | } else { |
1838 | tmp = stack.back(); |
1839 | stack.pop_back(); |
1840 | stack.back().ResolveValue(exe_ctx) = |
1841 | stack.back().ResolveValue(exe_ctx) >= tmp.ResolveValue(exe_ctx); |
1842 | } |
1843 | break; |
1844 | |
1845 | // OPCODE: DW_OP_gt |
1846 | // OPERANDS: none |
1847 | // DESCRIPTION: pops the top two stack values, compares using the |
1848 | // greater than (>) operator. |
1849 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1850 | // of the operation is true or the constant value 0 if the result of the |
1851 | // operation is false. |
1852 | case DW_OP_gt: |
1853 | if (stack.size() < 2) { |
1854 | if (error_ptr) |
1855 | error_ptr->SetErrorString( |
1856 | "Expression stack needs at least 2 items for DW_OP_gt."); |
1857 | return false; |
1858 | } else { |
1859 | tmp = stack.back(); |
1860 | stack.pop_back(); |
1861 | stack.back().ResolveValue(exe_ctx) = |
1862 | stack.back().ResolveValue(exe_ctx) > tmp.ResolveValue(exe_ctx); |
1863 | } |
1864 | break; |
1865 | |
1866 | // OPCODE: DW_OP_le |
1867 | // OPERANDS: none |
1868 | // DESCRIPTION: pops the top two stack values, compares using the |
1869 | // less than or equal to (<=) operator. |
1870 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1871 | // of the operation is true or the constant value 0 if the result of the |
1872 | // operation is false. |
1873 | case DW_OP_le: |
1874 | if (stack.size() < 2) { |
1875 | if (error_ptr) |
1876 | error_ptr->SetErrorString( |
1877 | "Expression stack needs at least 2 items for DW_OP_le."); |
1878 | return false; |
1879 | } else { |
1880 | tmp = stack.back(); |
1881 | stack.pop_back(); |
1882 | stack.back().ResolveValue(exe_ctx) = |
1883 | stack.back().ResolveValue(exe_ctx) <= tmp.ResolveValue(exe_ctx); |
1884 | } |
1885 | break; |
1886 | |
1887 | // OPCODE: DW_OP_lt |
1888 | // OPERANDS: none |
1889 | // DESCRIPTION: pops the top two stack values, compares using the |
1890 | // less than (<) operator. |
1891 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1892 | // of the operation is true or the constant value 0 if the result of the |
1893 | // operation is false. |
1894 | case DW_OP_lt: |
1895 | if (stack.size() < 2) { |
1896 | if (error_ptr) |
1897 | error_ptr->SetErrorString( |
1898 | "Expression stack needs at least 2 items for DW_OP_lt."); |
1899 | return false; |
1900 | } else { |
1901 | tmp = stack.back(); |
1902 | stack.pop_back(); |
1903 | stack.back().ResolveValue(exe_ctx) = |
1904 | stack.back().ResolveValue(exe_ctx) < tmp.ResolveValue(exe_ctx); |
1905 | } |
1906 | break; |
1907 | |
1908 | // OPCODE: DW_OP_ne |
1909 | // OPERANDS: none |
1910 | // DESCRIPTION: pops the top two stack values, compares using the |
1911 | // not equal (!=) operator. |
1912 | // STACK RESULT: push the constant value 1 onto the stack if the result |
1913 | // of the operation is true or the constant value 0 if the result of the |
1914 | // operation is false. |
1915 | case DW_OP_ne: |
1916 | if (stack.size() < 2) { |
1917 | if (error_ptr) |
1918 | error_ptr->SetErrorString( |
1919 | "Expression stack needs at least 2 items for DW_OP_ne."); |
1920 | return false; |
1921 | } else { |
1922 | tmp = stack.back(); |
1923 | stack.pop_back(); |
1924 | stack.back().ResolveValue(exe_ctx) = |
1925 | stack.back().ResolveValue(exe_ctx) != tmp.ResolveValue(exe_ctx); |
1926 | } |
1927 | break; |
1928 | |
1929 | // OPCODE: DW_OP_litn |
1930 | // OPERANDS: none |
1931 | // DESCRIPTION: encode the unsigned literal values from 0 through 31. |
1932 | // STACK RESULT: push the unsigned literal constant value onto the top |
1933 | // of the stack. |
1934 | case DW_OP_lit0: |
1935 | case DW_OP_lit1: |
1936 | case DW_OP_lit2: |
1937 | case DW_OP_lit3: |
1938 | case DW_OP_lit4: |
1939 | case DW_OP_lit5: |
1940 | case DW_OP_lit6: |
1941 | case DW_OP_lit7: |
1942 | case DW_OP_lit8: |
1943 | case DW_OP_lit9: |
1944 | case DW_OP_lit10: |
1945 | case DW_OP_lit11: |
1946 | case DW_OP_lit12: |
1947 | case DW_OP_lit13: |
1948 | case DW_OP_lit14: |
1949 | case DW_OP_lit15: |
1950 | case DW_OP_lit16: |
1951 | case DW_OP_lit17: |
1952 | case DW_OP_lit18: |
1953 | case DW_OP_lit19: |
1954 | case DW_OP_lit20: |
1955 | case DW_OP_lit21: |
1956 | case DW_OP_lit22: |
1957 | case DW_OP_lit23: |
1958 | case DW_OP_lit24: |
1959 | case DW_OP_lit25: |
1960 | case DW_OP_lit26: |
1961 | case DW_OP_lit27: |
1962 | case DW_OP_lit28: |
1963 | case DW_OP_lit29: |
1964 | case DW_OP_lit30: |
1965 | case DW_OP_lit31: |
1966 | stack.push_back(to_generic(op - DW_OP_lit0)); |
1967 | break; |
1968 | |
1969 | // OPCODE: DW_OP_regN |
1970 | // OPERANDS: none |
1971 | // DESCRIPTION: Push the value in register n on the top of the stack. |
1972 | case DW_OP_reg0: |
1973 | case DW_OP_reg1: |
1974 | case DW_OP_reg2: |
1975 | case DW_OP_reg3: |
1976 | case DW_OP_reg4: |
1977 | case DW_OP_reg5: |
1978 | case DW_OP_reg6: |
1979 | case DW_OP_reg7: |
1980 | case DW_OP_reg8: |
1981 | case DW_OP_reg9: |
1982 | case DW_OP_reg10: |
1983 | case DW_OP_reg11: |
1984 | case DW_OP_reg12: |
1985 | case DW_OP_reg13: |
1986 | case DW_OP_reg14: |
1987 | case DW_OP_reg15: |
1988 | case DW_OP_reg16: |
1989 | case DW_OP_reg17: |
1990 | case DW_OP_reg18: |
1991 | case DW_OP_reg19: |
1992 | case DW_OP_reg20: |
1993 | case DW_OP_reg21: |
1994 | case DW_OP_reg22: |
1995 | case DW_OP_reg23: |
1996 | case DW_OP_reg24: |
1997 | case DW_OP_reg25: |
1998 | case DW_OP_reg26: |
1999 | case DW_OP_reg27: |
2000 | case DW_OP_reg28: |
2001 | case DW_OP_reg29: |
2002 | case DW_OP_reg30: |
2003 | case DW_OP_reg31: { |
2004 | dwarf4_location_description_kind = Register; |
2005 | reg_num = op - DW_OP_reg0; |
2006 | |
2007 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, tmp)) |
2008 | stack.push_back(tmp); |
2009 | else |
2010 | return false; |
2011 | } break; |
2012 | // OPCODE: DW_OP_regx |
2013 | // OPERANDS: |
2014 | // ULEB128 literal operand that encodes the register. |
2015 | // DESCRIPTION: Push the value in register on the top of the stack. |
2016 | case DW_OP_regx: { |
2017 | dwarf4_location_description_kind = Register; |
2018 | reg_num = opcodes.GetULEB128(&offset); |
2019 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, tmp)) |
2020 | stack.push_back(tmp); |
2021 | else |
2022 | return false; |
2023 | } break; |
2024 | |
2025 | // OPCODE: DW_OP_bregN |
2026 | // OPERANDS: |
2027 | // SLEB128 offset from register N |
2028 | // DESCRIPTION: Value is in memory at the address specified by register |
2029 | // N plus an offset. |
2030 | case DW_OP_breg0: |
2031 | case DW_OP_breg1: |
2032 | case DW_OP_breg2: |
2033 | case DW_OP_breg3: |
2034 | case DW_OP_breg4: |
2035 | case DW_OP_breg5: |
2036 | case DW_OP_breg6: |
2037 | case DW_OP_breg7: |
2038 | case DW_OP_breg8: |
2039 | case DW_OP_breg9: |
2040 | case DW_OP_breg10: |
2041 | case DW_OP_breg11: |
2042 | case DW_OP_breg12: |
2043 | case DW_OP_breg13: |
2044 | case DW_OP_breg14: |
2045 | case DW_OP_breg15: |
2046 | case DW_OP_breg16: |
2047 | case DW_OP_breg17: |
2048 | case DW_OP_breg18: |
2049 | case DW_OP_breg19: |
2050 | case DW_OP_breg20: |
2051 | case DW_OP_breg21: |
2052 | case DW_OP_breg22: |
2053 | case DW_OP_breg23: |
2054 | case DW_OP_breg24: |
2055 | case DW_OP_breg25: |
2056 | case DW_OP_breg26: |
2057 | case DW_OP_breg27: |
2058 | case DW_OP_breg28: |
2059 | case DW_OP_breg29: |
2060 | case DW_OP_breg30: |
2061 | case DW_OP_breg31: { |
2062 | reg_num = op - DW_OP_breg0; |
2063 | |
2064 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, |
2065 | tmp)) { |
2066 | int64_t breg_offset = opcodes.GetSLEB128(&offset); |
2067 | tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset; |
2068 | tmp.ClearContext(); |
2069 | stack.push_back(tmp); |
2070 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2071 | } else |
2072 | return false; |
2073 | } break; |
2074 | // OPCODE: DW_OP_bregx |
2075 | // OPERANDS: 2 |
2076 | // ULEB128 literal operand that encodes the register. |
2077 | // SLEB128 offset from register N |
2078 | // DESCRIPTION: Value is in memory at the address specified by register |
2079 | // N plus an offset. |
2080 | case DW_OP_bregx: { |
2081 | reg_num = opcodes.GetULEB128(&offset); |
2082 | |
2083 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, |
2084 | tmp)) { |
2085 | int64_t breg_offset = opcodes.GetSLEB128(&offset); |
2086 | tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset; |
2087 | tmp.ClearContext(); |
2088 | stack.push_back(tmp); |
2089 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2090 | } else |
2091 | return false; |
2092 | } break; |
2093 | |
2094 | case DW_OP_fbreg: |
2095 | if (exe_ctx) { |
2096 | if (frame) { |
2097 | Scalar value; |
2098 | if (frame->GetFrameBaseValue(value, error_ptr)) { |
2099 | int64_t fbreg_offset = opcodes.GetSLEB128(&offset); |
2100 | value += fbreg_offset; |
2101 | stack.push_back(value); |
2102 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2103 | } else |
2104 | return false; |
2105 | } else { |
2106 | if (error_ptr) |
2107 | error_ptr->SetErrorString( |
2108 | "Invalid stack frame in context for DW_OP_fbreg opcode."); |
2109 | return false; |
2110 | } |
2111 | } else { |
2112 | if (error_ptr) |
2113 | error_ptr->SetErrorString( |
2114 | "NULL execution context for DW_OP_fbreg.\n"); |
2115 | return false; |
2116 | } |
2117 | |
2118 | break; |
2119 | |
2120 | // OPCODE: DW_OP_nop |
2121 | // OPERANDS: none |
2122 | // DESCRIPTION: A place holder. It has no effect on the location stack |
2123 | // or any of its values. |
2124 | case DW_OP_nop: |
2125 | break; |
2126 | |
2127 | // OPCODE: DW_OP_piece |
2128 | // OPERANDS: 1 |
2129 | // ULEB128: byte size of the piece |
2130 | // DESCRIPTION: The operand describes the size in bytes of the piece of |
2131 | // the object referenced by the DWARF expression whose result is at the top |
2132 | // of the stack. If the piece is located in a register, but does not occupy |
2133 | // the entire register, the placement of the piece within that register is |
2134 | // defined by the ABI. |
2135 | // |
2136 | // Many compilers store a single variable in sets of registers, or store a |
2137 | // variable partially in memory and partially in registers. DW_OP_piece |
2138 | // provides a way of describing how large a part of a variable a particular |
2139 | // DWARF expression refers to. |
2140 | case DW_OP_piece: { |
2141 | LocationDescriptionKind piece_locdesc = dwarf4_location_description_kind; |
2142 | // Reset for the next piece. |
2143 | dwarf4_location_description_kind = Memory; |
2144 | |
2145 | const uint64_t piece_byte_size = opcodes.GetULEB128(&offset); |
2146 | |
2147 | if (piece_byte_size > 0) { |
2148 | Value curr_piece; |
2149 | |
2150 | if (stack.empty()) { |
2151 | UpdateValueTypeFromLocationDescription( |
2152 | log, dwarf_cu, LocationDescriptionKind::Empty); |
2153 | // In a multi-piece expression, this means that the current piece is |
2154 | // not available. Fill with zeros for now by resizing the data and |
2155 | // appending it |
2156 | curr_piece.ResizeData(piece_byte_size); |
2157 | // Note that "0" is not a correct value for the unknown bits. |
2158 | // It would be better to also return a mask of valid bits together |
2159 | // with the expression result, so the debugger can print missing |
2160 | // members as "<optimized out>" or something. |
2161 | ::memset(curr_piece.GetBuffer().GetBytes(), 0, piece_byte_size); |
2162 | pieces.AppendDataToHostBuffer(curr_piece); |
2163 | } else { |
2164 | Status error; |
2165 | // Extract the current piece into "curr_piece" |
2166 | Value curr_piece_source_value(stack.back()); |
2167 | stack.pop_back(); |
2168 | UpdateValueTypeFromLocationDescription(log, dwarf_cu, piece_locdesc, |
2169 | &curr_piece_source_value); |
2170 | |
2171 | const Value::ValueType curr_piece_source_value_type = |
2172 | curr_piece_source_value.GetValueType(); |
2173 | switch (curr_piece_source_value_type) { |
2174 | case Value::ValueType::Invalid: |
2175 | return false; |
2176 | case Value::ValueType::LoadAddress: |
2177 | if (process) { |
2178 | if (curr_piece.ResizeData(piece_byte_size) == piece_byte_size) { |
2179 | lldb::addr_t load_addr = |
2180 | curr_piece_source_value.GetScalar().ULongLong( |
2181 | LLDB_INVALID_ADDRESS0xffffffffffffffffULL); |
2182 | if (process->ReadMemory( |
2183 | load_addr, curr_piece.GetBuffer().GetBytes(), |
2184 | piece_byte_size, error) != piece_byte_size) { |
2185 | if (error_ptr) |
2186 | error_ptr->SetErrorStringWithFormat( |
2187 | "failed to read memory DW_OP_piece(%" PRIu64"llu" |
2188 | ") from 0x%" PRIx64"llx", |
2189 | piece_byte_size, load_addr); |
2190 | return false; |
2191 | } |
2192 | } else { |
2193 | if (error_ptr) |
2194 | error_ptr->SetErrorStringWithFormat( |
2195 | "failed to resize the piece memory buffer for " |
2196 | "DW_OP_piece(%" PRIu64"llu" ")", |
2197 | piece_byte_size); |
2198 | return false; |
2199 | } |
2200 | } |
2201 | break; |
2202 | |
2203 | case Value::ValueType::FileAddress: |
2204 | case Value::ValueType::HostAddress: |
2205 | if (error_ptr) { |
2206 | lldb::addr_t addr = curr_piece_source_value.GetScalar().ULongLong( |
2207 | LLDB_INVALID_ADDRESS0xffffffffffffffffULL); |
2208 | error_ptr->SetErrorStringWithFormat( |
2209 | "failed to read memory DW_OP_piece(%" PRIu64"llu" |
2210 | ") from %s address 0x%" PRIx64"llx", |
2211 | piece_byte_size, curr_piece_source_value.GetValueType() == |
2212 | Value::ValueType::FileAddress |
2213 | ? "file" |
2214 | : "host", |
2215 | addr); |
2216 | } |
2217 | return false; |
2218 | |
2219 | case Value::ValueType::Scalar: { |
2220 | uint32_t bit_size = piece_byte_size * 8; |
2221 | uint32_t bit_offset = 0; |
2222 | Scalar &scalar = curr_piece_source_value.GetScalar(); |
2223 | if (!scalar.ExtractBitfield( |
2224 | bit_size, bit_offset)) { |
2225 | if (error_ptr) |
2226 | error_ptr->SetErrorStringWithFormat( |
2227 | "unable to extract %" PRIu64"llu" " bytes from a %" PRIu64"llu" |
2228 | " byte scalar value.", |
2229 | piece_byte_size, |
2230 | (uint64_t)curr_piece_source_value.GetScalar() |
2231 | .GetByteSize()); |
2232 | return false; |
2233 | } |
2234 | // Create curr_piece with bit_size. By default Scalar |
2235 | // grows to the nearest host integer type. |
2236 | llvm::APInt fail_value(1, 0, false); |
2237 | llvm::APInt ap_int = scalar.UInt128(fail_value); |
2238 | assert(ap_int.getBitWidth() >= bit_size)((void)0); |
2239 | llvm::ArrayRef<uint64_t> buf{ap_int.getRawData(), |
2240 | ap_int.getNumWords()}; |
2241 | curr_piece.GetScalar() = Scalar(llvm::APInt(bit_size, buf)); |
2242 | } break; |
2243 | } |
2244 | |
2245 | // Check if this is the first piece? |
2246 | if (op_piece_offset == 0) { |
2247 | // This is the first piece, we should push it back onto the stack |
2248 | // so subsequent pieces will be able to access this piece and add |
2249 | // to it. |
2250 | if (pieces.AppendDataToHostBuffer(curr_piece) == 0) { |
2251 | if (error_ptr) |
2252 | error_ptr->SetErrorString("failed to append piece data"); |
2253 | return false; |
2254 | } |
2255 | } else { |
2256 | // If this is the second or later piece there should be a value on |
2257 | // the stack. |
2258 | if (pieces.GetBuffer().GetByteSize() != op_piece_offset) { |
2259 | if (error_ptr) |
2260 | error_ptr->SetErrorStringWithFormat( |
2261 | "DW_OP_piece for offset %" PRIu64"llu" |
2262 | " but top of stack is of size %" PRIu64"llu", |
2263 | op_piece_offset, pieces.GetBuffer().GetByteSize()); |
2264 | return false; |
2265 | } |
2266 | |
2267 | if (pieces.AppendDataToHostBuffer(curr_piece) == 0) { |
2268 | if (error_ptr) |
2269 | error_ptr->SetErrorString("failed to append piece data"); |
2270 | return false; |
2271 | } |
2272 | } |
2273 | } |
2274 | op_piece_offset += piece_byte_size; |
2275 | } |
2276 | } break; |
2277 | |
2278 | case DW_OP_bit_piece: // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3); |
2279 | if (stack.size() < 1) { |
2280 | UpdateValueTypeFromLocationDescription(log, dwarf_cu, |
2281 | LocationDescriptionKind::Empty); |
2282 | // Reset for the next piece. |
2283 | dwarf4_location_description_kind = Memory; |
2284 | if (error_ptr) |
2285 | error_ptr->SetErrorString( |
2286 | "Expression stack needs at least 1 item for DW_OP_bit_piece."); |
2287 | return false; |
2288 | } else { |
2289 | UpdateValueTypeFromLocationDescription( |
2290 | log, dwarf_cu, dwarf4_location_description_kind, &stack.back()); |
2291 | // Reset for the next piece. |
2292 | dwarf4_location_description_kind = Memory; |
2293 | const uint64_t piece_bit_size = opcodes.GetULEB128(&offset); |
2294 | const uint64_t piece_bit_offset = opcodes.GetULEB128(&offset); |
2295 | switch (stack.back().GetValueType()) { |
2296 | case Value::ValueType::Invalid: |
2297 | return false; |
2298 | case Value::ValueType::Scalar: { |
2299 | if (!stack.back().GetScalar().ExtractBitfield(piece_bit_size, |
2300 | piece_bit_offset)) { |
2301 | if (error_ptr) |
2302 | error_ptr->SetErrorStringWithFormat( |
2303 | "unable to extract %" PRIu64"llu" " bit value with %" PRIu64"llu" |
2304 | " bit offset from a %" PRIu64"llu" " bit scalar value.", |
2305 | piece_bit_size, piece_bit_offset, |
2306 | (uint64_t)(stack.back().GetScalar().GetByteSize() * 8)); |
2307 | return false; |
2308 | } |
2309 | } break; |
2310 | |
2311 | case Value::ValueType::FileAddress: |
2312 | case Value::ValueType::LoadAddress: |
2313 | case Value::ValueType::HostAddress: |
2314 | if (error_ptr) { |
2315 | error_ptr->SetErrorStringWithFormat( |
2316 | "unable to extract DW_OP_bit_piece(bit_size = %" PRIu64"llu" |
2317 | ", bit_offset = %" PRIu64"llu" ") from an address value.", |
2318 | piece_bit_size, piece_bit_offset); |
2319 | } |
2320 | return false; |
2321 | } |
2322 | } |
2323 | break; |
2324 | |
2325 | // OPCODE: DW_OP_implicit_value |
2326 | // OPERANDS: 2 |
2327 | // ULEB128 size of the value block in bytes |
2328 | // uint8_t* block bytes encoding value in target's memory |
2329 | // representation |
2330 | // DESCRIPTION: Value is immediately stored in block in the debug info with |
2331 | // the memory representation of the target. |
2332 | case DW_OP_implicit_value: { |
2333 | dwarf4_location_description_kind = Implicit; |
2334 | |
2335 | const uint32_t len = opcodes.GetULEB128(&offset); |
2336 | const void *data = opcodes.GetData(&offset, len); |
2337 | |
2338 | if (!data) { |
2339 | 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("/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_implicit_value: could not be read data" ); } while (0); |
2340 | 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); |
2341 | 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);; |
2342 | return false; |
2343 | } |
2344 | |
2345 | Value result(data, len); |
2346 | stack.push_back(result); |
2347 | break; |
2348 | } |
2349 | |
2350 | case DW_OP_implicit_pointer: { |
2351 | dwarf4_location_description_kind = Implicit; |
Value stored to 'dwarf4_location_description_kind' is never read | |
2352 | 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);; |
2353 | return false; |
2354 | } |
2355 | |
2356 | // OPCODE: DW_OP_push_object_address |
2357 | // OPERANDS: none |
2358 | // DESCRIPTION: Pushes the address of the object currently being |
2359 | // evaluated as part of evaluation of a user presented expression. This |
2360 | // object may correspond to an independent variable described by its own |
2361 | // DIE or it may be a component of an array, structure, or class whose |
2362 | // address has been dynamically determined by an earlier step during user |
2363 | // expression evaluation. |
2364 | case DW_OP_push_object_address: |
2365 | if (object_address_ptr) |
2366 | stack.push_back(*object_address_ptr); |
2367 | else { |
2368 | if (error_ptr) |
2369 | error_ptr->SetErrorString("DW_OP_push_object_address used without " |
2370 | "specifying an object address"); |
2371 | return false; |
2372 | } |
2373 | break; |
2374 | |
2375 | // OPCODE: DW_OP_call2 |
2376 | // OPERANDS: |
2377 | // uint16_t compile unit relative offset of a DIE |
2378 | // DESCRIPTION: Performs subroutine calls during evaluation |
2379 | // of a DWARF expression. The operand is the 2-byte unsigned offset of a |
2380 | // debugging information entry in the current compilation unit. |
2381 | // |
2382 | // Operand interpretation is exactly like that for DW_FORM_ref2. |
2383 | // |
2384 | // This operation transfers control of DWARF expression evaluation to the |
2385 | // DW_AT_location attribute of the referenced DIE. If there is no such |
2386 | // attribute, then there is no effect. Execution of the DWARF expression of |
2387 | // a DW_AT_location attribute may add to and/or remove from values on the |
2388 | // stack. Execution returns to the point following the call when the end of |
2389 | // the attribute is reached. Values on the stack at the time of the call |
2390 | // may be used as parameters by the called expression and values left on |
2391 | // the stack by the called expression may be used as return values by prior |
2392 | // agreement between the calling and called expressions. |
2393 | case DW_OP_call2: |
2394 | if (error_ptr) |
2395 | error_ptr->SetErrorString("Unimplemented opcode DW_OP_call2."); |
2396 | return false; |
2397 | // OPCODE: DW_OP_call4 |
2398 | // OPERANDS: 1 |
2399 | // uint32_t compile unit relative offset of a DIE |
2400 | // DESCRIPTION: Performs a subroutine call during evaluation of a DWARF |
2401 | // expression. For DW_OP_call4, the operand is a 4-byte unsigned offset of |
2402 | // a debugging information entry in the current compilation unit. |
2403 | // |
2404 | // Operand interpretation DW_OP_call4 is exactly like that for |
2405 | // DW_FORM_ref4. |
2406 | // |
2407 | // This operation transfers control of DWARF expression evaluation to the |
2408 | // DW_AT_location attribute of the referenced DIE. If there is no such |
2409 | // attribute, then there is no effect. Execution of the DWARF expression of |
2410 | // a DW_AT_location attribute may add to and/or remove from values on the |
2411 | // stack. Execution returns to the point following the call when the end of |
2412 | // the attribute is reached. Values on the stack at the time of the call |
2413 | // may be used as parameters by the called expression and values left on |
2414 | // the stack by the called expression may be used as return values by prior |
2415 | // agreement between the calling and called expressions. |
2416 | case DW_OP_call4: |
2417 | if (error_ptr) |
2418 | error_ptr->SetErrorString("Unimplemented opcode DW_OP_call4."); |
2419 | return false; |
2420 | |
2421 | // OPCODE: DW_OP_stack_value |
2422 | // OPERANDS: None |
2423 | // DESCRIPTION: Specifies that the object does not exist in memory but |
2424 | // rather is a constant value. The value from the top of the stack is the |
2425 | // value to be used. This is the actual object value and not the location. |
2426 | case DW_OP_stack_value: |
2427 | dwarf4_location_description_kind = Implicit; |
2428 | if (stack.empty()) { |
2429 | if (error_ptr) |
2430 | error_ptr->SetErrorString( |
2431 | "Expression stack needs at least 1 item for DW_OP_stack_value."); |
2432 | return false; |
2433 | } |
2434 | stack.back().SetValueType(Value::ValueType::Scalar); |
2435 | break; |
2436 | |
2437 | // OPCODE: DW_OP_convert |
2438 | // OPERANDS: 1 |
2439 | // A ULEB128 that is either a DIE offset of a |
2440 | // DW_TAG_base_type or 0 for the generic (pointer-sized) type. |
2441 | // |
2442 | // DESCRIPTION: Pop the top stack element, convert it to a |
2443 | // different type, and push the result. |
2444 | case DW_OP_convert: { |
2445 | if (stack.size() < 1) { |
2446 | if (error_ptr) |
2447 | error_ptr->SetErrorString( |
2448 | "Expression stack needs at least 1 item for DW_OP_convert."); |
2449 | return false; |
2450 | } |
2451 | const uint64_t die_offset = opcodes.GetULEB128(&offset); |
2452 | uint64_t bit_size; |
2453 | bool sign; |
2454 | if (die_offset == 0) { |
2455 | // The generic type has the size of an address on the target |
2456 | // machine and an unspecified signedness. Scalar has no |
2457 | // "unspecified signedness", so we use unsigned types. |
2458 | if (!module_sp) { |
2459 | if (error_ptr) |
2460 | error_ptr->SetErrorString("No module"); |
2461 | return false; |
2462 | } |
2463 | sign = false; |
2464 | bit_size = module_sp->GetArchitecture().GetAddressByteSize() * 8; |
2465 | if (!bit_size) { |
2466 | if (error_ptr) |
2467 | error_ptr->SetErrorString("unspecified architecture"); |
2468 | return false; |
2469 | } |
2470 | } else { |
2471 | // Retrieve the type DIE that the value is being converted to. |
2472 | // FIXME: the constness has annoying ripple effects. |
2473 | DWARFDIE die = const_cast<DWARFUnit *>(dwarf_cu)->GetDIE(die_offset); |
2474 | if (!die) { |
2475 | if (error_ptr) |
2476 | error_ptr->SetErrorString("Cannot resolve DW_OP_convert type DIE"); |
2477 | return false; |
2478 | } |
2479 | uint64_t encoding = |
2480 | die.GetAttributeValueAsUnsigned(DW_AT_encoding, DW_ATE_hi_user); |
2481 | bit_size = die.GetAttributeValueAsUnsigned(DW_AT_byte_size, 0) * 8; |
2482 | if (!bit_size) |
2483 | bit_size = die.GetAttributeValueAsUnsigned(DW_AT_bit_size, 0); |
2484 | if (!bit_size) { |
2485 | if (error_ptr) |
2486 | error_ptr->SetErrorString("Unsupported type size in DW_OP_convert"); |
2487 | return false; |
2488 | } |
2489 | switch (encoding) { |
2490 | case DW_ATE_signed: |
2491 | case DW_ATE_signed_char: |
2492 | sign = true; |
2493 | break; |
2494 | case DW_ATE_unsigned: |
2495 | case DW_ATE_unsigned_char: |
2496 | sign = false; |
2497 | break; |
2498 | default: |
2499 | if (error_ptr) |
2500 | error_ptr->SetErrorString("Unsupported encoding in DW_OP_convert"); |
2501 | return false; |
2502 | } |
2503 | } |
2504 | Scalar &top = stack.back().ResolveValue(exe_ctx); |
2505 | top.TruncOrExtendTo(bit_size, sign); |
2506 | break; |
2507 | } |
2508 | |
2509 | // OPCODE: DW_OP_call_frame_cfa |
2510 | // OPERANDS: None |
2511 | // DESCRIPTION: Specifies a DWARF expression that pushes the value of |
2512 | // the canonical frame address consistent with the call frame information |
2513 | // located in .debug_frame (or in the FDEs of the eh_frame section). |
2514 | case DW_OP_call_frame_cfa: |
2515 | if (frame) { |
2516 | // Note that we don't have to parse FDEs because this DWARF expression |
2517 | // is commonly evaluated with a valid stack frame. |
2518 | StackID id = frame->GetStackID(); |
2519 | addr_t cfa = id.GetCallFrameAddress(); |
2520 | if (cfa != LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
2521 | stack.push_back(Scalar(cfa)); |
2522 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2523 | } else if (error_ptr) |
2524 | error_ptr->SetErrorString("Stack frame does not include a canonical " |
2525 | "frame address for DW_OP_call_frame_cfa " |
2526 | "opcode."); |
2527 | } else { |
2528 | if (error_ptr) |
2529 | error_ptr->SetErrorString("Invalid stack frame in context for " |
2530 | "DW_OP_call_frame_cfa opcode."); |
2531 | return false; |
2532 | } |
2533 | break; |
2534 | |
2535 | // OPCODE: DW_OP_form_tls_address (or the old pre-DWARFv3 vendor extension |
2536 | // opcode, DW_OP_GNU_push_tls_address) |
2537 | // OPERANDS: none |
2538 | // DESCRIPTION: Pops a TLS offset from the stack, converts it to |
2539 | // an address in the current thread's thread-local storage block, and |
2540 | // pushes it on the stack. |
2541 | case DW_OP_form_tls_address: |
2542 | case DW_OP_GNU_push_tls_address: { |
2543 | if (stack.size() < 1) { |
2544 | if (error_ptr) { |
2545 | if (op == DW_OP_form_tls_address) |
2546 | error_ptr->SetErrorString( |
2547 | "DW_OP_form_tls_address needs an argument."); |
2548 | else |
2549 | error_ptr->SetErrorString( |
2550 | "DW_OP_GNU_push_tls_address needs an argument."); |
2551 | } |
2552 | return false; |
2553 | } |
2554 | |
2555 | if (!exe_ctx || !module_sp) { |
2556 | if (error_ptr) |
2557 | error_ptr->SetErrorString("No context to evaluate TLS within."); |
2558 | return false; |
2559 | } |
2560 | |
2561 | Thread *thread = exe_ctx->GetThreadPtr(); |
2562 | if (!thread) { |
2563 | if (error_ptr) |
2564 | error_ptr->SetErrorString("No thread to evaluate TLS within."); |
2565 | return false; |
2566 | } |
2567 | |
2568 | // Lookup the TLS block address for this thread and module. |
2569 | const addr_t tls_file_addr = |
2570 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS0xffffffffffffffffULL); |
2571 | const addr_t tls_load_addr = |
2572 | thread->GetThreadLocalData(module_sp, tls_file_addr); |
2573 | |
2574 | if (tls_load_addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) { |
2575 | if (error_ptr) |
2576 | error_ptr->SetErrorString( |
2577 | "No TLS data currently exists for this thread."); |
2578 | return false; |
2579 | } |
2580 | |
2581 | stack.back().GetScalar() = tls_load_addr; |
2582 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
2583 | } break; |
2584 | |
2585 | // OPCODE: DW_OP_addrx (DW_OP_GNU_addr_index is the legacy name.) |
2586 | // OPERANDS: 1 |
2587 | // ULEB128: index to the .debug_addr section |
2588 | // DESCRIPTION: Pushes an address to the stack from the .debug_addr |
2589 | // section with the base address specified by the DW_AT_addr_base attribute |
2590 | // and the 0 based index is the ULEB128 encoded index. |
2591 | case DW_OP_addrx: |
2592 | case DW_OP_GNU_addr_index: { |
2593 | if (!dwarf_cu) { |
2594 | if (error_ptr) |
2595 | error_ptr->SetErrorString("DW_OP_GNU_addr_index found without a " |
2596 | "compile unit being specified"); |
2597 | return false; |
2598 | } |
2599 | uint64_t index = opcodes.GetULEB128(&offset); |
2600 | lldb::addr_t value = ReadAddressFromDebugAddrSection(dwarf_cu, index); |
2601 | stack.push_back(Scalar(value)); |
2602 | stack.back().SetValueType(Value::ValueType::FileAddress); |
2603 | } break; |
2604 | |
2605 | // OPCODE: DW_OP_GNU_const_index |
2606 | // OPERANDS: 1 |
2607 | // ULEB128: index to the .debug_addr section |
2608 | // DESCRIPTION: Pushes an constant with the size of a machine address to |
2609 | // the stack from the .debug_addr section with the base address specified |
2610 | // by the DW_AT_addr_base attribute and the 0 based index is the ULEB128 |
2611 | // encoded index. |
2612 | case DW_OP_GNU_const_index: { |
2613 | if (!dwarf_cu) { |
2614 | if (error_ptr) |
2615 | error_ptr->SetErrorString("DW_OP_GNU_const_index found without a " |
2616 | "compile unit being specified"); |
2617 | return false; |
2618 | } |
2619 | uint64_t index = opcodes.GetULEB128(&offset); |
2620 | lldb::addr_t value = ReadAddressFromDebugAddrSection(dwarf_cu, index); |
2621 | stack.push_back(Scalar(value)); |
2622 | } break; |
2623 | |
2624 | case DW_OP_GNU_entry_value: |
2625 | case DW_OP_entry_value: { |
2626 | if (!Evaluate_DW_OP_entry_value(stack, exe_ctx, reg_ctx, opcodes, offset, |
2627 | error_ptr, log)) { |
2628 | 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); |
2629 | 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);; |
2630 | return false; |
2631 | } |
2632 | break; |
2633 | } |
2634 | |
2635 | default: |
2636 | if (error_ptr) |
2637 | error_ptr->SetErrorStringWithFormatv( |
2638 | "Unhandled opcode {0} in DWARFExpression", LocationAtom(op)); |
2639 | return false; |
2640 | } |
2641 | } |
2642 | |
2643 | if (stack.empty()) { |
2644 | // Nothing on the stack, check if we created a piece value from DW_OP_piece |
2645 | // or DW_OP_bit_piece opcodes |
2646 | if (pieces.GetBuffer().GetByteSize()) { |
2647 | result = pieces; |
2648 | return true; |
2649 | } |
2650 | if (error_ptr) |
2651 | error_ptr->SetErrorString("Stack empty after evaluation."); |
2652 | return false; |
2653 | } |
2654 | |
2655 | UpdateValueTypeFromLocationDescription( |
2656 | log, dwarf_cu, dwarf4_location_description_kind, &stack.back()); |
2657 | |
2658 | if (log && log->GetVerbose()) { |
2659 | size_t count = stack.size(); |
2660 | LLDB_LOGF(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack after operation has %" "llu" " values:" , (uint64_t)count); } while (0) |
2661 | "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 %" "llu" " values:" , (uint64_t)count); } while (0); |
2662 | for (size_t i = 0; i < count; ++i) { |
2663 | StreamString new_value; |
2664 | new_value.Printf("[%" PRIu64"llu" "]", (uint64_t)i); |
2665 | stack[i].Dump(&new_value); |
2666 | 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); |
2667 | } |
2668 | } |
2669 | result = stack.back(); |
2670 | return true; // Return true on success |
2671 | } |
2672 | |
2673 | static DataExtractor ToDataExtractor(const llvm::DWARFLocationExpression &loc, |
2674 | ByteOrder byte_order, uint32_t addr_size) { |
2675 | auto buffer_sp = |
2676 | std::make_shared<DataBufferHeap>(loc.Expr.data(), loc.Expr.size()); |
2677 | return DataExtractor(buffer_sp, byte_order, addr_size); |
2678 | } |
2679 | |
2680 | llvm::Optional<DataExtractor> |
2681 | DWARFExpression::GetLocationExpression(addr_t load_function_start, |
2682 | addr_t addr) const { |
2683 | Log *log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)); |
2684 | |
2685 | std::unique_ptr<llvm::DWARFLocationTable> loctable_up = |
2686 | m_dwarf_cu->GetLocationTable(m_data); |
2687 | llvm::Optional<DataExtractor> result; |
2688 | uint64_t offset = 0; |
2689 | auto lookup_addr = |
2690 | [&](uint32_t index) -> llvm::Optional<llvm::object::SectionedAddress> { |
2691 | addr_t address = ReadAddressFromDebugAddrSection(m_dwarf_cu, index); |
2692 | if (address == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) |
2693 | return llvm::None; |
2694 | return llvm::object::SectionedAddress{address}; |
2695 | }; |
2696 | auto process_list = [&](llvm::Expected<llvm::DWARFLocationExpression> loc) { |
2697 | if (!loc) { |
2698 | 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), "/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "{0}"); } else ::llvm::consumeError(::std::move(error_private )); } while (0); |
2699 | return true; |
2700 | } |
2701 | if (loc->Range) { |
2702 | // This relocates low_pc and high_pc by adding the difference between the |
2703 | // function file address, and the actual address it is loaded in memory. |
2704 | addr_t slide = load_function_start - m_loclist_addresses->func_file_addr; |
2705 | loc->Range->LowPC += slide; |
2706 | loc->Range->HighPC += slide; |
2707 | |
2708 | if (loc->Range->LowPC <= addr && addr < loc->Range->HighPC) |
2709 | result = ToDataExtractor(*loc, m_data.GetByteOrder(), |
2710 | m_data.GetAddressByteSize()); |
2711 | } |
2712 | return !result; |
2713 | }; |
2714 | llvm::Error E = loctable_up->visitAbsoluteLocationList( |
2715 | offset, llvm::object::SectionedAddress{m_loclist_addresses->cu_file_addr}, |
2716 | lookup_addr, process_list); |
2717 | if (E) |
2718 | LLDB_LOG_ERROR(log, std::move(E), "{0}")do { ::lldb_private::Log *log_private = (log); ::llvm::Error error_private = (std::move(E)); if (log_private && error_private) { log_private->FormatError(::std::move(error_private), "/usr/src/gnu/usr.bin/clang/liblldbExpression/../../../llvm/lldb/source/Expression/DWARFExpression.cpp" , __func__, "{0}"); } else ::llvm::consumeError(::std::move(error_private )); } while (0); |
2719 | return result; |
2720 | } |
2721 | |
2722 | bool DWARFExpression::MatchesOperand(StackFrame &frame, |
2723 | const Instruction::Operand &operand) { |
2724 | using namespace OperandMatchers; |
2725 | |
2726 | RegisterContextSP reg_ctx_sp = frame.GetRegisterContext(); |
2727 | if (!reg_ctx_sp) { |
2728 | return false; |
2729 | } |
2730 | |
2731 | DataExtractor opcodes; |
2732 | if (IsLocationList()) { |
2733 | SymbolContext sc = frame.GetSymbolContext(eSymbolContextFunction); |
2734 | if (!sc.function) |
2735 | return false; |
2736 | |
2737 | addr_t load_function_start = |
2738 | sc.function->GetAddressRange().GetBaseAddress().GetFileAddress(); |
2739 | if (load_function_start == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) |
2740 | return false; |
2741 | |
2742 | addr_t pc = frame.GetFrameCodeAddress().GetLoadAddress( |
2743 | frame.CalculateTarget().get()); |
2744 | |
2745 | if (llvm::Optional<DataExtractor> expr = GetLocationExpression(load_function_start, pc)) |
2746 | opcodes = std::move(*expr); |
2747 | else |
2748 | return false; |
2749 | } else |
2750 | opcodes = m_data; |
2751 | |
2752 | |
2753 | lldb::offset_t op_offset = 0; |
2754 | uint8_t opcode = opcodes.GetU8(&op_offset); |
2755 | |
2756 | if (opcode == DW_OP_fbreg) { |
2757 | int64_t offset = opcodes.GetSLEB128(&op_offset); |
2758 | |
2759 | DWARFExpression *fb_expr = frame.GetFrameBaseExpression(nullptr); |
2760 | if (!fb_expr) { |
2761 | return false; |
2762 | } |
2763 | |
2764 | auto recurse = [&frame, fb_expr](const Instruction::Operand &child) { |
2765 | return fb_expr->MatchesOperand(frame, child); |
2766 | }; |
2767 | |
2768 | if (!offset && |
2769 | MatchUnaryOp(MatchOpType(Instruction::Operand::Type::Dereference), |
2770 | recurse)(operand)) { |
2771 | return true; |
2772 | } |
2773 | |
2774 | return MatchUnaryOp( |
2775 | MatchOpType(Instruction::Operand::Type::Dereference), |
2776 | MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum), |
2777 | MatchImmOp(offset), recurse))(operand); |
2778 | } |
2779 | |
2780 | bool dereference = false; |
2781 | const RegisterInfo *reg = nullptr; |
2782 | int64_t offset = 0; |
2783 | |
2784 | if (opcode >= DW_OP_reg0 && opcode <= DW_OP_reg31) { |
2785 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, opcode - DW_OP_reg0); |
2786 | } else if (opcode >= DW_OP_breg0 && opcode <= DW_OP_breg31) { |
2787 | offset = opcodes.GetSLEB128(&op_offset); |
2788 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, opcode - DW_OP_breg0); |
2789 | } else if (opcode == DW_OP_regx) { |
2790 | uint32_t reg_num = static_cast<uint32_t>(opcodes.GetULEB128(&op_offset)); |
2791 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, reg_num); |
2792 | } else if (opcode == DW_OP_bregx) { |
2793 | uint32_t reg_num = static_cast<uint32_t>(opcodes.GetULEB128(&op_offset)); |
2794 | offset = opcodes.GetSLEB128(&op_offset); |
2795 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, reg_num); |
2796 | } else { |
2797 | return false; |
2798 | } |
2799 | |
2800 | if (!reg) { |
2801 | return false; |
2802 | } |
2803 | |
2804 | if (dereference) { |
2805 | if (!offset && |
2806 | MatchUnaryOp(MatchOpType(Instruction::Operand::Type::Dereference), |
2807 | MatchRegOp(*reg))(operand)) { |
2808 | return true; |
2809 | } |
2810 | |
2811 | return MatchUnaryOp( |
2812 | MatchOpType(Instruction::Operand::Type::Dereference), |
2813 | MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum), |
2814 | MatchRegOp(*reg), |
2815 | MatchImmOp(offset)))(operand); |
2816 | } else { |
2817 | return MatchRegOp(*reg)(operand); |
2818 | } |
2819 | } |
2820 |