| File: | build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/lldb/source/Expression/DWARFExpression.cpp |
| Warning: | line 2189, column 9 Value stored to 'dwarf4_location_description_kind' is never read |
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| 1 | //===-- DWARFExpression.cpp -----------------------------------------------===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #include "lldb/Expression/DWARFExpression.h" |
| 10 | |
| 11 | #include <cinttypes> |
| 12 | |
| 13 | #include <vector> |
| 14 | |
| 15 | #include "lldb/Core/Module.h" |
| 16 | #include "lldb/Core/Value.h" |
| 17 | #include "lldb/Core/dwarf.h" |
| 18 | #include "lldb/Utility/DataEncoder.h" |
| 19 | #include "lldb/Utility/LLDBLog.h" |
| 20 | #include "lldb/Utility/Log.h" |
| 21 | #include "lldb/Utility/RegisterValue.h" |
| 22 | #include "lldb/Utility/Scalar.h" |
| 23 | #include "lldb/Utility/StreamString.h" |
| 24 | #include "lldb/Utility/VMRange.h" |
| 25 | |
| 26 | #include "lldb/Host/Host.h" |
| 27 | #include "lldb/Utility/Endian.h" |
| 28 | |
| 29 | #include "lldb/Symbol/Function.h" |
| 30 | |
| 31 | #include "lldb/Target/ABI.h" |
| 32 | #include "lldb/Target/ExecutionContext.h" |
| 33 | #include "lldb/Target/Process.h" |
| 34 | #include "lldb/Target/RegisterContext.h" |
| 35 | #include "lldb/Target/StackFrame.h" |
| 36 | #include "lldb/Target/StackID.h" |
| 37 | #include "lldb/Target/Target.h" |
| 38 | #include "lldb/Target/Thread.h" |
| 39 | #include "llvm/DebugInfo/DWARF/DWARFDebugLoc.h" |
| 40 | #include "llvm/DebugInfo/DWARF/DWARFExpression.h" |
| 41 | |
| 42 | #include "Plugins/SymbolFile/DWARF/DWARFUnit.h" |
| 43 | |
| 44 | using namespace lldb; |
| 45 | using namespace lldb_private; |
| 46 | using namespace lldb_private::dwarf; |
| 47 | |
| 48 | // DWARFExpression constructor |
| 49 | DWARFExpression::DWARFExpression() : m_data() {} |
| 50 | |
| 51 | DWARFExpression::DWARFExpression(const DataExtractor &data) : m_data(data) {} |
| 52 | |
| 53 | // Destructor |
| 54 | DWARFExpression::~DWARFExpression() = default; |
| 55 | |
| 56 | bool DWARFExpression::IsValid() const { return m_data.GetByteSize() > 0; } |
| 57 | |
| 58 | void DWARFExpression::UpdateValue(uint64_t const_value, |
| 59 | lldb::offset_t const_value_byte_size, |
| 60 | uint8_t addr_byte_size) { |
| 61 | if (!const_value_byte_size) |
| 62 | return; |
| 63 | |
| 64 | m_data.SetData( |
| 65 | DataBufferSP(new DataBufferHeap(&const_value, const_value_byte_size))); |
| 66 | m_data.SetByteOrder(endian::InlHostByteOrder()); |
| 67 | m_data.SetAddressByteSize(addr_byte_size); |
| 68 | } |
| 69 | |
| 70 | void DWARFExpression::DumpLocation(Stream *s, lldb::DescriptionLevel level, |
| 71 | ABI *abi) const { |
| 72 | llvm::DWARFExpression(m_data.GetAsLLVM(), m_data.GetAddressByteSize()) |
| 73 | .print(s->AsRawOstream(), llvm::DIDumpOptions(), |
| 74 | abi ? &abi->GetMCRegisterInfo() : nullptr, nullptr); |
| 75 | } |
| 76 | |
| 77 | RegisterKind DWARFExpression::GetRegisterKind() const { return m_reg_kind; } |
| 78 | |
| 79 | void DWARFExpression::SetRegisterKind(RegisterKind reg_kind) { |
| 80 | m_reg_kind = reg_kind; |
| 81 | } |
| 82 | |
| 83 | |
| 84 | static bool ReadRegisterValueAsScalar(RegisterContext *reg_ctx, |
| 85 | lldb::RegisterKind reg_kind, |
| 86 | uint32_t reg_num, Status *error_ptr, |
| 87 | Value &value) { |
| 88 | if (reg_ctx == nullptr) { |
| 89 | if (error_ptr) |
| 90 | error_ptr->SetErrorString("No register context in frame.\n"); |
| 91 | } else { |
| 92 | uint32_t native_reg = |
| 93 | reg_ctx->ConvertRegisterKindToRegisterNumber(reg_kind, reg_num); |
| 94 | if (native_reg == LLDB_INVALID_REGNUM(4294967295U)) { |
| 95 | if (error_ptr) |
| 96 | error_ptr->SetErrorStringWithFormat("Unable to convert register " |
| 97 | "kind=%u reg_num=%u to a native " |
| 98 | "register number.\n", |
| 99 | reg_kind, reg_num); |
| 100 | } else { |
| 101 | const RegisterInfo *reg_info = |
| 102 | reg_ctx->GetRegisterInfoAtIndex(native_reg); |
| 103 | RegisterValue reg_value; |
| 104 | if (reg_ctx->ReadRegister(reg_info, reg_value)) { |
| 105 | if (reg_value.GetScalarValue(value.GetScalar())) { |
| 106 | value.SetValueType(Value::ValueType::Scalar); |
| 107 | value.SetContext(Value::ContextType::RegisterInfo, |
| 108 | const_cast<RegisterInfo *>(reg_info)); |
| 109 | if (error_ptr) |
| 110 | error_ptr->Clear(); |
| 111 | return true; |
| 112 | } else { |
| 113 | // If we get this error, then we need to implement a value buffer in |
| 114 | // the dwarf expression evaluation function... |
| 115 | if (error_ptr) |
| 116 | error_ptr->SetErrorStringWithFormat( |
| 117 | "register %s can't be converted to a scalar value", |
| 118 | reg_info->name); |
| 119 | } |
| 120 | } else { |
| 121 | if (error_ptr) |
| 122 | error_ptr->SetErrorStringWithFormat("register %s is not available", |
| 123 | reg_info->name); |
| 124 | } |
| 125 | } |
| 126 | } |
| 127 | return false; |
| 128 | } |
| 129 | |
| 130 | /// Return the length in bytes of the set of operands for \p op. No guarantees |
| 131 | /// are made on the state of \p data after this call. |
| 132 | static offset_t GetOpcodeDataSize(const DataExtractor &data, |
| 133 | const lldb::offset_t data_offset, |
| 134 | const uint8_t op) { |
| 135 | lldb::offset_t offset = data_offset; |
| 136 | switch (op) { |
| 137 | case DW_OP_addr: |
| 138 | case DW_OP_call_ref: // 0x9a 1 address sized offset of DIE (DWARF3) |
| 139 | return data.GetAddressByteSize(); |
| 140 | |
| 141 | // Opcodes with no arguments |
| 142 | case DW_OP_deref: // 0x06 |
| 143 | case DW_OP_dup: // 0x12 |
| 144 | case DW_OP_drop: // 0x13 |
| 145 | case DW_OP_over: // 0x14 |
| 146 | case DW_OP_swap: // 0x16 |
| 147 | case DW_OP_rot: // 0x17 |
| 148 | case DW_OP_xderef: // 0x18 |
| 149 | case DW_OP_abs: // 0x19 |
| 150 | case DW_OP_and: // 0x1a |
| 151 | case DW_OP_div: // 0x1b |
| 152 | case DW_OP_minus: // 0x1c |
| 153 | case DW_OP_mod: // 0x1d |
| 154 | case DW_OP_mul: // 0x1e |
| 155 | case DW_OP_neg: // 0x1f |
| 156 | case DW_OP_not: // 0x20 |
| 157 | case DW_OP_or: // 0x21 |
| 158 | case DW_OP_plus: // 0x22 |
| 159 | case DW_OP_shl: // 0x24 |
| 160 | case DW_OP_shr: // 0x25 |
| 161 | case DW_OP_shra: // 0x26 |
| 162 | case DW_OP_xor: // 0x27 |
| 163 | case DW_OP_eq: // 0x29 |
| 164 | case DW_OP_ge: // 0x2a |
| 165 | case DW_OP_gt: // 0x2b |
| 166 | case DW_OP_le: // 0x2c |
| 167 | case DW_OP_lt: // 0x2d |
| 168 | case DW_OP_ne: // 0x2e |
| 169 | case DW_OP_lit0: // 0x30 |
| 170 | case DW_OP_lit1: // 0x31 |
| 171 | case DW_OP_lit2: // 0x32 |
| 172 | case DW_OP_lit3: // 0x33 |
| 173 | case DW_OP_lit4: // 0x34 |
| 174 | case DW_OP_lit5: // 0x35 |
| 175 | case DW_OP_lit6: // 0x36 |
| 176 | case DW_OP_lit7: // 0x37 |
| 177 | case DW_OP_lit8: // 0x38 |
| 178 | case DW_OP_lit9: // 0x39 |
| 179 | case DW_OP_lit10: // 0x3A |
| 180 | case DW_OP_lit11: // 0x3B |
| 181 | case DW_OP_lit12: // 0x3C |
| 182 | case DW_OP_lit13: // 0x3D |
| 183 | case DW_OP_lit14: // 0x3E |
| 184 | case DW_OP_lit15: // 0x3F |
| 185 | case DW_OP_lit16: // 0x40 |
| 186 | case DW_OP_lit17: // 0x41 |
| 187 | case DW_OP_lit18: // 0x42 |
| 188 | case DW_OP_lit19: // 0x43 |
| 189 | case DW_OP_lit20: // 0x44 |
| 190 | case DW_OP_lit21: // 0x45 |
| 191 | case DW_OP_lit22: // 0x46 |
| 192 | case DW_OP_lit23: // 0x47 |
| 193 | case DW_OP_lit24: // 0x48 |
| 194 | case DW_OP_lit25: // 0x49 |
| 195 | case DW_OP_lit26: // 0x4A |
| 196 | case DW_OP_lit27: // 0x4B |
| 197 | case DW_OP_lit28: // 0x4C |
| 198 | case DW_OP_lit29: // 0x4D |
| 199 | case DW_OP_lit30: // 0x4E |
| 200 | case DW_OP_lit31: // 0x4f |
| 201 | case DW_OP_reg0: // 0x50 |
| 202 | case DW_OP_reg1: // 0x51 |
| 203 | case DW_OP_reg2: // 0x52 |
| 204 | case DW_OP_reg3: // 0x53 |
| 205 | case DW_OP_reg4: // 0x54 |
| 206 | case DW_OP_reg5: // 0x55 |
| 207 | case DW_OP_reg6: // 0x56 |
| 208 | case DW_OP_reg7: // 0x57 |
| 209 | case DW_OP_reg8: // 0x58 |
| 210 | case DW_OP_reg9: // 0x59 |
| 211 | case DW_OP_reg10: // 0x5A |
| 212 | case DW_OP_reg11: // 0x5B |
| 213 | case DW_OP_reg12: // 0x5C |
| 214 | case DW_OP_reg13: // 0x5D |
| 215 | case DW_OP_reg14: // 0x5E |
| 216 | case DW_OP_reg15: // 0x5F |
| 217 | case DW_OP_reg16: // 0x60 |
| 218 | case DW_OP_reg17: // 0x61 |
| 219 | case DW_OP_reg18: // 0x62 |
| 220 | case DW_OP_reg19: // 0x63 |
| 221 | case DW_OP_reg20: // 0x64 |
| 222 | case DW_OP_reg21: // 0x65 |
| 223 | case DW_OP_reg22: // 0x66 |
| 224 | case DW_OP_reg23: // 0x67 |
| 225 | case DW_OP_reg24: // 0x68 |
| 226 | case DW_OP_reg25: // 0x69 |
| 227 | case DW_OP_reg26: // 0x6A |
| 228 | case DW_OP_reg27: // 0x6B |
| 229 | case DW_OP_reg28: // 0x6C |
| 230 | case DW_OP_reg29: // 0x6D |
| 231 | case DW_OP_reg30: // 0x6E |
| 232 | case DW_OP_reg31: // 0x6F |
| 233 | case DW_OP_nop: // 0x96 |
| 234 | case DW_OP_push_object_address: // 0x97 DWARF3 |
| 235 | case DW_OP_form_tls_address: // 0x9b DWARF3 |
| 236 | case DW_OP_call_frame_cfa: // 0x9c DWARF3 |
| 237 | case DW_OP_stack_value: // 0x9f DWARF4 |
| 238 | case DW_OP_GNU_push_tls_address: // 0xe0 GNU extension |
| 239 | return 0; |
| 240 | |
| 241 | // Opcodes with a single 1 byte arguments |
| 242 | case DW_OP_const1u: // 0x08 1 1-byte constant |
| 243 | case DW_OP_const1s: // 0x09 1 1-byte constant |
| 244 | case DW_OP_pick: // 0x15 1 1-byte stack index |
| 245 | case DW_OP_deref_size: // 0x94 1 1-byte size of data retrieved |
| 246 | case DW_OP_xderef_size: // 0x95 1 1-byte size of data retrieved |
| 247 | return 1; |
| 248 | |
| 249 | // Opcodes with a single 2 byte arguments |
| 250 | case DW_OP_const2u: // 0x0a 1 2-byte constant |
| 251 | case DW_OP_const2s: // 0x0b 1 2-byte constant |
| 252 | case DW_OP_skip: // 0x2f 1 signed 2-byte constant |
| 253 | case DW_OP_bra: // 0x28 1 signed 2-byte constant |
| 254 | case DW_OP_call2: // 0x98 1 2-byte offset of DIE (DWARF3) |
| 255 | return 2; |
| 256 | |
| 257 | // Opcodes with a single 4 byte arguments |
| 258 | case DW_OP_const4u: // 0x0c 1 4-byte constant |
| 259 | case DW_OP_const4s: // 0x0d 1 4-byte constant |
| 260 | case DW_OP_call4: // 0x99 1 4-byte offset of DIE (DWARF3) |
| 261 | return 4; |
| 262 | |
| 263 | // Opcodes with a single 8 byte arguments |
| 264 | case DW_OP_const8u: // 0x0e 1 8-byte constant |
| 265 | case DW_OP_const8s: // 0x0f 1 8-byte constant |
| 266 | return 8; |
| 267 | |
| 268 | // All opcodes that have a single ULEB (signed or unsigned) argument |
| 269 | case DW_OP_addrx: // 0xa1 1 ULEB128 index |
| 270 | case DW_OP_constu: // 0x10 1 ULEB128 constant |
| 271 | case DW_OP_consts: // 0x11 1 SLEB128 constant |
| 272 | case DW_OP_plus_uconst: // 0x23 1 ULEB128 addend |
| 273 | case DW_OP_breg0: // 0x70 1 ULEB128 register |
| 274 | case DW_OP_breg1: // 0x71 1 ULEB128 register |
| 275 | case DW_OP_breg2: // 0x72 1 ULEB128 register |
| 276 | case DW_OP_breg3: // 0x73 1 ULEB128 register |
| 277 | case DW_OP_breg4: // 0x74 1 ULEB128 register |
| 278 | case DW_OP_breg5: // 0x75 1 ULEB128 register |
| 279 | case DW_OP_breg6: // 0x76 1 ULEB128 register |
| 280 | case DW_OP_breg7: // 0x77 1 ULEB128 register |
| 281 | case DW_OP_breg8: // 0x78 1 ULEB128 register |
| 282 | case DW_OP_breg9: // 0x79 1 ULEB128 register |
| 283 | case DW_OP_breg10: // 0x7a 1 ULEB128 register |
| 284 | case DW_OP_breg11: // 0x7b 1 ULEB128 register |
| 285 | case DW_OP_breg12: // 0x7c 1 ULEB128 register |
| 286 | case DW_OP_breg13: // 0x7d 1 ULEB128 register |
| 287 | case DW_OP_breg14: // 0x7e 1 ULEB128 register |
| 288 | case DW_OP_breg15: // 0x7f 1 ULEB128 register |
| 289 | case DW_OP_breg16: // 0x80 1 ULEB128 register |
| 290 | case DW_OP_breg17: // 0x81 1 ULEB128 register |
| 291 | case DW_OP_breg18: // 0x82 1 ULEB128 register |
| 292 | case DW_OP_breg19: // 0x83 1 ULEB128 register |
| 293 | case DW_OP_breg20: // 0x84 1 ULEB128 register |
| 294 | case DW_OP_breg21: // 0x85 1 ULEB128 register |
| 295 | case DW_OP_breg22: // 0x86 1 ULEB128 register |
| 296 | case DW_OP_breg23: // 0x87 1 ULEB128 register |
| 297 | case DW_OP_breg24: // 0x88 1 ULEB128 register |
| 298 | case DW_OP_breg25: // 0x89 1 ULEB128 register |
| 299 | case DW_OP_breg26: // 0x8a 1 ULEB128 register |
| 300 | case DW_OP_breg27: // 0x8b 1 ULEB128 register |
| 301 | case DW_OP_breg28: // 0x8c 1 ULEB128 register |
| 302 | case DW_OP_breg29: // 0x8d 1 ULEB128 register |
| 303 | case DW_OP_breg30: // 0x8e 1 ULEB128 register |
| 304 | case DW_OP_breg31: // 0x8f 1 ULEB128 register |
| 305 | case DW_OP_regx: // 0x90 1 ULEB128 register |
| 306 | case DW_OP_fbreg: // 0x91 1 SLEB128 offset |
| 307 | case DW_OP_piece: // 0x93 1 ULEB128 size of piece addressed |
| 308 | case DW_OP_GNU_addr_index: // 0xfb 1 ULEB128 index |
| 309 | case DW_OP_GNU_const_index: // 0xfc 1 ULEB128 index |
| 310 | data.Skip_LEB128(&offset); |
| 311 | return offset - data_offset; |
| 312 | |
| 313 | // All opcodes that have a 2 ULEB (signed or unsigned) arguments |
| 314 | case DW_OP_bregx: // 0x92 2 ULEB128 register followed by SLEB128 offset |
| 315 | case DW_OP_bit_piece: // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3); |
| 316 | data.Skip_LEB128(&offset); |
| 317 | data.Skip_LEB128(&offset); |
| 318 | return offset - data_offset; |
| 319 | |
| 320 | case DW_OP_implicit_value: // 0x9e ULEB128 size followed by block of that size |
| 321 | // (DWARF4) |
| 322 | { |
| 323 | uint64_t block_len = data.Skip_LEB128(&offset); |
| 324 | offset += block_len; |
| 325 | return offset - data_offset; |
| 326 | } |
| 327 | |
| 328 | case DW_OP_GNU_entry_value: |
| 329 | case DW_OP_entry_value: // 0xa3 ULEB128 size + variable-length block |
| 330 | { |
| 331 | uint64_t subexpr_len = data.GetULEB128(&offset); |
| 332 | return (offset - data_offset) + subexpr_len; |
| 333 | } |
| 334 | |
| 335 | default: |
| 336 | break; |
| 337 | } |
| 338 | return LLDB_INVALID_OFFSET(18446744073709551615UL); |
| 339 | } |
| 340 | |
| 341 | lldb::addr_t DWARFExpression::GetLocation_DW_OP_addr(const DWARFUnit *dwarf_cu, |
| 342 | uint32_t op_addr_idx, |
| 343 | bool &error) const { |
| 344 | error = false; |
| 345 | lldb::offset_t offset = 0; |
| 346 | uint32_t curr_op_addr_idx = 0; |
| 347 | while (m_data.ValidOffset(offset)) { |
| 348 | const uint8_t op = m_data.GetU8(&offset); |
| 349 | |
| 350 | if (op == DW_OP_addr) { |
| 351 | const lldb::addr_t op_file_addr = m_data.GetAddress(&offset); |
| 352 | if (curr_op_addr_idx == op_addr_idx) |
| 353 | return op_file_addr; |
| 354 | ++curr_op_addr_idx; |
| 355 | } else if (op == DW_OP_GNU_addr_index || op == DW_OP_addrx) { |
| 356 | uint64_t index = m_data.GetULEB128(&offset); |
| 357 | if (curr_op_addr_idx == op_addr_idx) { |
| 358 | if (!dwarf_cu) { |
| 359 | error = true; |
| 360 | break; |
| 361 | } |
| 362 | |
| 363 | return dwarf_cu->ReadAddressFromDebugAddrSection(index); |
| 364 | } |
| 365 | ++curr_op_addr_idx; |
| 366 | } else { |
| 367 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
| 368 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) { |
| 369 | error = true; |
| 370 | break; |
| 371 | } |
| 372 | offset += op_arg_size; |
| 373 | } |
| 374 | } |
| 375 | return LLDB_INVALID_ADDRESS(18446744073709551615UL); |
| 376 | } |
| 377 | |
| 378 | bool DWARFExpression::Update_DW_OP_addr(lldb::addr_t file_addr) { |
| 379 | lldb::offset_t offset = 0; |
| 380 | while (m_data.ValidOffset(offset)) { |
| 381 | const uint8_t op = m_data.GetU8(&offset); |
| 382 | |
| 383 | if (op == DW_OP_addr) { |
| 384 | const uint32_t addr_byte_size = m_data.GetAddressByteSize(); |
| 385 | // We have to make a copy of the data as we don't know if this data is |
| 386 | // from a read only memory mapped buffer, so we duplicate all of the data |
| 387 | // first, then modify it, and if all goes well, we then replace the data |
| 388 | // for this expression |
| 389 | |
| 390 | // Make en encoder that contains a copy of the location expression data |
| 391 | // so we can write the address into the buffer using the correct byte |
| 392 | // order. |
| 393 | DataEncoder encoder(m_data.GetDataStart(), m_data.GetByteSize(), |
| 394 | m_data.GetByteOrder(), addr_byte_size); |
| 395 | |
| 396 | // Replace the address in the new buffer |
| 397 | if (encoder.PutAddress(offset, file_addr) == UINT32_MAX(4294967295U)) |
| 398 | return false; |
| 399 | |
| 400 | // All went well, so now we can reset the data using a shared pointer to |
| 401 | // the heap data so "m_data" will now correctly manage the heap data. |
| 402 | m_data.SetData(encoder.GetDataBuffer()); |
| 403 | return true; |
| 404 | } else { |
| 405 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
| 406 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) |
| 407 | break; |
| 408 | offset += op_arg_size; |
| 409 | } |
| 410 | } |
| 411 | return false; |
| 412 | } |
| 413 | |
| 414 | bool DWARFExpression::ContainsThreadLocalStorage() const { |
| 415 | lldb::offset_t offset = 0; |
| 416 | while (m_data.ValidOffset(offset)) { |
| 417 | const uint8_t op = m_data.GetU8(&offset); |
| 418 | |
| 419 | if (op == DW_OP_form_tls_address || op == DW_OP_GNU_push_tls_address) |
| 420 | return true; |
| 421 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
| 422 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) |
| 423 | return false; |
| 424 | offset += op_arg_size; |
| 425 | } |
| 426 | return false; |
| 427 | } |
| 428 | bool DWARFExpression::LinkThreadLocalStorage( |
| 429 | std::function<lldb::addr_t(lldb::addr_t file_addr)> const |
| 430 | &link_address_callback) { |
| 431 | const uint32_t addr_byte_size = m_data.GetAddressByteSize(); |
| 432 | // We have to make a copy of the data as we don't know if this data is from a |
| 433 | // read only memory mapped buffer, so we duplicate all of the data first, |
| 434 | // then modify it, and if all goes well, we then replace the data for this |
| 435 | // expression. |
| 436 | // Make en encoder that contains a copy of the location expression data so we |
| 437 | // can write the address into the buffer using the correct byte order. |
| 438 | DataEncoder encoder(m_data.GetDataStart(), m_data.GetByteSize(), |
| 439 | m_data.GetByteOrder(), addr_byte_size); |
| 440 | |
| 441 | lldb::offset_t offset = 0; |
| 442 | lldb::offset_t const_offset = 0; |
| 443 | lldb::addr_t const_value = 0; |
| 444 | size_t const_byte_size = 0; |
| 445 | while (m_data.ValidOffset(offset)) { |
| 446 | const uint8_t op = m_data.GetU8(&offset); |
| 447 | |
| 448 | bool decoded_data = false; |
| 449 | switch (op) { |
| 450 | case DW_OP_const4u: |
| 451 | // Remember the const offset in case we later have a |
| 452 | // DW_OP_form_tls_address or DW_OP_GNU_push_tls_address |
| 453 | const_offset = offset; |
| 454 | const_value = m_data.GetU32(&offset); |
| 455 | decoded_data = true; |
| 456 | const_byte_size = 4; |
| 457 | break; |
| 458 | |
| 459 | case DW_OP_const8u: |
| 460 | // Remember the const offset in case we later have a |
| 461 | // DW_OP_form_tls_address or DW_OP_GNU_push_tls_address |
| 462 | const_offset = offset; |
| 463 | const_value = m_data.GetU64(&offset); |
| 464 | decoded_data = true; |
| 465 | const_byte_size = 8; |
| 466 | break; |
| 467 | |
| 468 | case DW_OP_form_tls_address: |
| 469 | case DW_OP_GNU_push_tls_address: |
| 470 | // DW_OP_form_tls_address and DW_OP_GNU_push_tls_address must be preceded |
| 471 | // by a file address on the stack. We assume that DW_OP_const4u or |
| 472 | // DW_OP_const8u is used for these values, and we check that the last |
| 473 | // opcode we got before either of these was DW_OP_const4u or |
| 474 | // DW_OP_const8u. If so, then we can link the value accordingly. For |
| 475 | // Darwin, the value in the DW_OP_const4u or DW_OP_const8u is the file |
| 476 | // address of a structure that contains a function pointer, the pthread |
| 477 | // key and the offset into the data pointed to by the pthread key. So we |
| 478 | // must link this address and also set the module of this expression to |
| 479 | // the new_module_sp so we can resolve the file address correctly |
| 480 | if (const_byte_size > 0) { |
| 481 | lldb::addr_t linked_file_addr = link_address_callback(const_value); |
| 482 | if (linked_file_addr == LLDB_INVALID_ADDRESS(18446744073709551615UL)) |
| 483 | return false; |
| 484 | // Replace the address in the new buffer |
| 485 | if (encoder.PutUnsigned(const_offset, const_byte_size, |
| 486 | linked_file_addr) == UINT32_MAX(4294967295U)) |
| 487 | return false; |
| 488 | } |
| 489 | break; |
| 490 | |
| 491 | default: |
| 492 | const_offset = 0; |
| 493 | const_value = 0; |
| 494 | const_byte_size = 0; |
| 495 | break; |
| 496 | } |
| 497 | |
| 498 | if (!decoded_data) { |
| 499 | const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op); |
| 500 | if (op_arg_size == LLDB_INVALID_OFFSET(18446744073709551615UL)) |
| 501 | return false; |
| 502 | else |
| 503 | offset += op_arg_size; |
| 504 | } |
| 505 | } |
| 506 | |
| 507 | m_data.SetData(encoder.GetDataBuffer()); |
| 508 | return true; |
| 509 | } |
| 510 | |
| 511 | static bool Evaluate_DW_OP_entry_value(std::vector<Value> &stack, |
| 512 | ExecutionContext *exe_ctx, |
| 513 | RegisterContext *reg_ctx, |
| 514 | const DataExtractor &opcodes, |
| 515 | lldb::offset_t &opcode_offset, |
| 516 | Status *error_ptr, Log *log) { |
| 517 | // DW_OP_entry_value(sub-expr) describes the location a variable had upon |
| 518 | // function entry: this variable location is presumed to be optimized out at |
| 519 | // the current PC value. The caller of the function may have call site |
| 520 | // information that describes an alternate location for the variable (e.g. a |
| 521 | // constant literal, or a spilled stack value) in the parent frame. |
| 522 | // |
| 523 | // Example (this is pseudo-code & pseudo-DWARF, but hopefully illustrative): |
| 524 | // |
| 525 | // void child(int &sink, int x) { |
| 526 | // ... |
| 527 | // /* "x" gets optimized out. */ |
| 528 | // |
| 529 | // /* The location of "x" here is: DW_OP_entry_value($reg2). */ |
| 530 | // ++sink; |
| 531 | // } |
| 532 | // |
| 533 | // void parent() { |
| 534 | // int sink; |
| 535 | // |
| 536 | // /* |
| 537 | // * The callsite information emitted here is: |
| 538 | // * |
| 539 | // * DW_TAG_call_site |
| 540 | // * DW_AT_return_pc ... (for "child(sink, 123);") |
| 541 | // * DW_TAG_call_site_parameter (for "sink") |
| 542 | // * DW_AT_location ($reg1) |
| 543 | // * DW_AT_call_value ($SP - 8) |
| 544 | // * DW_TAG_call_site_parameter (for "x") |
| 545 | // * DW_AT_location ($reg2) |
| 546 | // * DW_AT_call_value ($literal 123) |
| 547 | // * |
| 548 | // * DW_TAG_call_site |
| 549 | // * DW_AT_return_pc ... (for "child(sink, 456);") |
| 550 | // * ... |
| 551 | // */ |
| 552 | // child(sink, 123); |
| 553 | // child(sink, 456); |
| 554 | // } |
| 555 | // |
| 556 | // When the program stops at "++sink" within `child`, the debugger determines |
| 557 | // the call site by analyzing the return address. Once the call site is found, |
| 558 | // the debugger determines which parameter is referenced by DW_OP_entry_value |
| 559 | // and evaluates the corresponding location for that parameter in `parent`. |
| 560 | |
| 561 | // 1. Find the function which pushed the current frame onto the stack. |
| 562 | if ((!exe_ctx || !exe_ctx->HasTargetScope()) || !reg_ctx) { |
| 563 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no exe/reg context")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no exe/reg context") ; } while (0); |
| 564 | return false; |
| 565 | } |
| 566 | |
| 567 | StackFrame *current_frame = exe_ctx->GetFramePtr(); |
| 568 | Thread *thread = exe_ctx->GetThreadPtr(); |
| 569 | if (!current_frame || !thread) { |
| 570 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no current frame/thread")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no current frame/thread" ); } while (0); |
| 571 | return false; |
| 572 | } |
| 573 | |
| 574 | Target &target = exe_ctx->GetTargetRef(); |
| 575 | StackFrameSP parent_frame = nullptr; |
| 576 | addr_t return_pc = LLDB_INVALID_ADDRESS(18446744073709551615UL); |
| 577 | uint32_t current_frame_idx = current_frame->GetFrameIndex(); |
| 578 | uint32_t num_frames = thread->GetStackFrameCount(); |
| 579 | for (uint32_t parent_frame_idx = current_frame_idx + 1; |
| 580 | parent_frame_idx < num_frames; ++parent_frame_idx) { |
| 581 | parent_frame = thread->GetStackFrameAtIndex(parent_frame_idx); |
| 582 | // Require a valid sequence of frames. |
| 583 | if (!parent_frame) |
| 584 | break; |
| 585 | |
| 586 | // Record the first valid return address, even if this is an inlined frame, |
| 587 | // in order to look up the associated call edge in the first non-inlined |
| 588 | // parent frame. |
| 589 | if (return_pc == LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
| 590 | return_pc = parent_frame->GetFrameCodeAddress().GetLoadAddress(&target); |
| 591 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0) |
| 592 | "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0) |
| 593 | return_pc)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}" , return_pc); } while (0); |
| 594 | } |
| 595 | |
| 596 | // If we've found an inlined frame, skip it (these have no call site |
| 597 | // parameters). |
| 598 | if (parent_frame->IsInlined()) |
| 599 | continue; |
| 600 | |
| 601 | // We've found the first non-inlined parent frame. |
| 602 | break; |
| 603 | } |
| 604 | if (!parent_frame || !parent_frame->GetRegisterContext()) { |
| 605 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no parent frame with reg ctx")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no parent frame with reg ctx" ); } while (0); |
| 606 | return false; |
| 607 | } |
| 608 | |
| 609 | Function *parent_func = |
| 610 | parent_frame->GetSymbolContext(eSymbolContextFunction).function; |
| 611 | if (!parent_func) { |
| 612 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no parent function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no parent function") ; } while (0); |
| 613 | return false; |
| 614 | } |
| 615 | |
| 616 | // 2. Find the call edge in the parent function responsible for creating the |
| 617 | // current activation. |
| 618 | Function *current_func = |
| 619 | current_frame->GetSymbolContext(eSymbolContextFunction).function; |
| 620 | if (!current_func) { |
| 621 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no current function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no current function" ); } while (0); |
| 622 | return false; |
| 623 | } |
| 624 | |
| 625 | CallEdge *call_edge = nullptr; |
| 626 | ModuleList &modlist = target.GetImages(); |
| 627 | ExecutionContext parent_exe_ctx = *exe_ctx; |
| 628 | parent_exe_ctx.SetFrameSP(parent_frame); |
| 629 | if (!parent_frame->IsArtificial()) { |
| 630 | // If the parent frame is not artificial, the current activation may be |
| 631 | // produced by an ambiguous tail call. In this case, refuse to proceed. |
| 632 | call_edge = parent_func->GetCallEdgeForReturnAddress(return_pc, target); |
| 633 | if (!call_edge) { |
| 634 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0) |
| 635 | "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} "do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0) |
| 636 | "in parent frame {1}",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0) |
| 637 | return_pc, parent_func->GetName())do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} " "in parent frame {1}", return_pc, parent_func->GetName()) ; } while (0); |
| 638 | return false; |
| 639 | } |
| 640 | Function *callee_func = call_edge->GetCallee(modlist, parent_exe_ctx); |
| 641 | if (callee_func != current_func) { |
| 642 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: ambiguous call sequence, "do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: ambiguous call sequence, " "can't find real parent frame"); } while (0) |
| 643 | "can't find real parent frame")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: ambiguous call sequence, " "can't find real parent frame"); } while (0); |
| 644 | return false; |
| 645 | } |
| 646 | } else { |
| 647 | // The StackFrameList solver machinery has deduced that an unambiguous tail |
| 648 | // call sequence that produced the current activation. The first edge in |
| 649 | // the parent that points to the current function must be valid. |
| 650 | for (auto &edge : parent_func->GetTailCallingEdges()) { |
| 651 | if (edge->GetCallee(modlist, parent_exe_ctx) == current_func) { |
| 652 | call_edge = edge.get(); |
| 653 | break; |
| 654 | } |
| 655 | } |
| 656 | } |
| 657 | if (!call_edge) { |
| 658 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent "do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent " "to current function"); } while (0) |
| 659 | "to current function")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent " "to current function"); } while (0); |
| 660 | return false; |
| 661 | } |
| 662 | |
| 663 | // 3. Attempt to locate the DW_OP_entry_value expression in the set of |
| 664 | // available call site parameters. If found, evaluate the corresponding |
| 665 | // parameter in the context of the parent frame. |
| 666 | const uint32_t subexpr_len = opcodes.GetULEB128(&opcode_offset); |
| 667 | const void *subexpr_data = opcodes.GetData(&opcode_offset, subexpr_len); |
| 668 | if (!subexpr_data) { |
| 669 | LLDB_LOG(log, "Evaluate_DW_OP_entry_value: subexpr could not be read")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: subexpr could not be read" ); } while (0); |
| 670 | return false; |
| 671 | } |
| 672 | |
| 673 | const CallSiteParameter *matched_param = nullptr; |
| 674 | for (const CallSiteParameter ¶m : call_edge->GetCallSiteParameters()) { |
| 675 | DataExtractor param_subexpr_extractor; |
| 676 | if (!param.LocationInCallee.GetExpressionData(param_subexpr_extractor)) |
| 677 | continue; |
| 678 | lldb::offset_t param_subexpr_offset = 0; |
| 679 | const void *param_subexpr_data = |
| 680 | param_subexpr_extractor.GetData(¶m_subexpr_offset, subexpr_len); |
| 681 | if (!param_subexpr_data || |
| 682 | param_subexpr_extractor.BytesLeft(param_subexpr_offset) != 0) |
| 683 | continue; |
| 684 | |
| 685 | // At this point, the DW_OP_entry_value sub-expression and the callee-side |
| 686 | // expression in the call site parameter are known to have the same length. |
| 687 | // Check whether they are equal. |
| 688 | // |
| 689 | // Note that an equality check is sufficient: the contents of the |
| 690 | // DW_OP_entry_value subexpression are only used to identify the right call |
| 691 | // site parameter in the parent, and do not require any special handling. |
| 692 | if (memcmp(subexpr_data, param_subexpr_data, subexpr_len) == 0) { |
| 693 | matched_param = ¶m; |
| 694 | break; |
| 695 | } |
| 696 | } |
| 697 | if (!matched_param) { |
| 698 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no matching call site param found" ); } while (0) |
| 699 | "Evaluate_DW_OP_entry_value: no matching call site param found")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: no matching call site param found" ); } while (0); |
| 700 | return false; |
| 701 | } |
| 702 | |
| 703 | // TODO: Add support for DW_OP_push_object_address within a DW_OP_entry_value |
| 704 | // subexpresion whenever llvm does. |
| 705 | Value result; |
| 706 | const DWARFExpressionList ¶m_expr = matched_param->LocationInCaller; |
| 707 | if (!param_expr.Evaluate(&parent_exe_ctx, |
| 708 | parent_frame->GetRegisterContext().get(), |
| 709 | LLDB_INVALID_ADDRESS(18446744073709551615UL), |
| 710 | /*initial_value_ptr=*/nullptr, |
| 711 | /*object_address_ptr=*/nullptr, result, error_ptr)) { |
| 712 | LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: call site param evaluation failed" ); } while (0) |
| 713 | "Evaluate_DW_OP_entry_value: call site param evaluation failed")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_entry_value: call site param evaluation failed" ); } while (0); |
| 714 | return false; |
| 715 | } |
| 716 | |
| 717 | stack.push_back(result); |
| 718 | return true; |
| 719 | } |
| 720 | |
| 721 | namespace { |
| 722 | /// The location description kinds described by the DWARF v5 |
| 723 | /// specification. Composite locations are handled out-of-band and |
| 724 | /// thus aren't part of the enum. |
| 725 | enum LocationDescriptionKind { |
| 726 | Empty, |
| 727 | Memory, |
| 728 | Register, |
| 729 | Implicit |
| 730 | /* Composite*/ |
| 731 | }; |
| 732 | /// Adjust value's ValueType according to the kind of location description. |
| 733 | void UpdateValueTypeFromLocationDescription(Log *log, const DWARFUnit *dwarf_cu, |
| 734 | LocationDescriptionKind kind, |
| 735 | Value *value = nullptr) { |
| 736 | // Note that this function is conflating DWARF expressions with |
| 737 | // DWARF location descriptions. Perhaps it would be better to define |
| 738 | // a wrapper for DWARFExpression::Eval() that deals with DWARF |
| 739 | // location descriptions (which consist of one or more DWARF |
| 740 | // expressions). But doing this would mean we'd also need factor the |
| 741 | // handling of DW_OP_(bit_)piece out of this function. |
| 742 | if (dwarf_cu && dwarf_cu->GetVersion() >= 4) { |
| 743 | const char *log_msg = "DWARF location description kind: %s"; |
| 744 | switch (kind) { |
| 745 | case Empty: |
| 746 | LLDB_LOGF(log, log_msg, "Empty")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Empty"); } while (0); |
| 747 | break; |
| 748 | case Memory: |
| 749 | LLDB_LOGF(log, log_msg, "Memory")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Memory"); } while (0); |
| 750 | if (value->GetValueType() == Value::ValueType::Scalar) |
| 751 | value->SetValueType(Value::ValueType::LoadAddress); |
| 752 | break; |
| 753 | case Register: |
| 754 | LLDB_LOGF(log, log_msg, "Register")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Register"); } while (0); |
| 755 | value->SetValueType(Value::ValueType::Scalar); |
| 756 | break; |
| 757 | case Implicit: |
| 758 | LLDB_LOGF(log, log_msg, "Implicit")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf(log_msg, "Implicit"); } while (0); |
| 759 | if (value->GetValueType() == Value::ValueType::LoadAddress) |
| 760 | value->SetValueType(Value::ValueType::Scalar); |
| 761 | break; |
| 762 | } |
| 763 | } |
| 764 | } |
| 765 | } // namespace |
| 766 | |
| 767 | /// Helper function to move common code used to resolve a file address and turn |
| 768 | /// into a load address. |
| 769 | /// |
| 770 | /// \param exe_ctx Pointer to the execution context |
| 771 | /// \param module_sp shared_ptr contains the module if we have one |
| 772 | /// \param error_ptr pointer to Status object if we have one |
| 773 | /// \param dw_op_type C-style string used to vary the error output |
| 774 | /// \param file_addr the file address we are trying to resolve and turn into a |
| 775 | /// load address |
| 776 | /// \param so_addr out parameter, will be set to load address or section offset |
| 777 | /// \param check_sectionoffset bool which determines if having a section offset |
| 778 | /// but not a load address is considerd a success |
| 779 | /// \returns llvm::Optional containing the load address if resolving and getting |
| 780 | /// the load address succeed or an empty Optinal otherwise. If |
| 781 | /// check_sectionoffset is true we consider LLDB_INVALID_ADDRESS a |
| 782 | /// success if so_addr.IsSectionOffset() is true. |
| 783 | static llvm::Optional<lldb::addr_t> |
| 784 | ResolveLoadAddress(ExecutionContext *exe_ctx, lldb::ModuleSP &module_sp, |
| 785 | Status *error_ptr, const char *dw_op_type, |
| 786 | lldb::addr_t file_addr, Address &so_addr, |
| 787 | bool check_sectionoffset = false) { |
| 788 | if (!module_sp) { |
| 789 | if (error_ptr) |
| 790 | error_ptr->SetErrorStringWithFormat( |
| 791 | "need module to resolve file address for %s", dw_op_type); |
| 792 | return {}; |
| 793 | } |
| 794 | |
| 795 | if (!module_sp->ResolveFileAddress(file_addr, so_addr)) { |
| 796 | if (error_ptr) |
| 797 | error_ptr->SetErrorString("failed to resolve file address in module"); |
| 798 | return {}; |
| 799 | } |
| 800 | |
| 801 | addr_t load_addr = so_addr.GetLoadAddress(exe_ctx->GetTargetPtr()); |
| 802 | |
| 803 | if (load_addr == LLDB_INVALID_ADDRESS(18446744073709551615UL) && |
| 804 | (check_sectionoffset && !so_addr.IsSectionOffset())) { |
| 805 | if (error_ptr) |
| 806 | error_ptr->SetErrorString("failed to resolve load address"); |
| 807 | return {}; |
| 808 | } |
| 809 | |
| 810 | return load_addr; |
| 811 | } |
| 812 | |
| 813 | /// Helper function to move common code used to load sized data from a uint8_t |
| 814 | /// buffer. |
| 815 | /// |
| 816 | /// \param addr_bytes uint8_t buffer containg raw data |
| 817 | /// \param size_addr_bytes how large is the underlying raw data |
| 818 | /// \param byte_order what is the byter order of the underlyig data |
| 819 | /// \param size How much of the underlying data we want to use |
| 820 | /// \return The underlying data converted into a Scalar |
| 821 | static Scalar DerefSizeExtractDataHelper(uint8_t *addr_bytes, |
| 822 | size_t size_addr_bytes, |
| 823 | ByteOrder byte_order, size_t size) { |
| 824 | DataExtractor addr_data(addr_bytes, size_addr_bytes, byte_order, size); |
| 825 | |
| 826 | lldb::offset_t addr_data_offset = 0; |
| 827 | if (size <= 8) |
| 828 | return addr_data.GetMaxU64(&addr_data_offset, size); |
| 829 | else |
| 830 | return addr_data.GetAddress(&addr_data_offset); |
| 831 | } |
| 832 | |
| 833 | bool DWARFExpression::Evaluate( |
| 834 | ExecutionContext *exe_ctx, RegisterContext *reg_ctx, |
| 835 | lldb::ModuleSP module_sp, const DataExtractor &opcodes, |
| 836 | const DWARFUnit *dwarf_cu, const lldb::RegisterKind reg_kind, |
| 837 | const Value *initial_value_ptr, const Value *object_address_ptr, |
| 838 | Value &result, Status *error_ptr) { |
| 839 | |
| 840 | if (opcodes.GetByteSize() == 0) { |
| 841 | if (error_ptr) |
| 842 | error_ptr->SetErrorString( |
| 843 | "no location, value may have been optimized out"); |
| 844 | return false; |
| 845 | } |
| 846 | std::vector<Value> stack; |
| 847 | |
| 848 | Process *process = nullptr; |
| 849 | StackFrame *frame = nullptr; |
| 850 | |
| 851 | if (exe_ctx) { |
| 852 | process = exe_ctx->GetProcessPtr(); |
| 853 | frame = exe_ctx->GetFramePtr(); |
| 854 | } |
| 855 | if (reg_ctx == nullptr && frame) |
| 856 | reg_ctx = frame->GetRegisterContext().get(); |
| 857 | |
| 858 | if (initial_value_ptr) |
| 859 | stack.push_back(*initial_value_ptr); |
| 860 | |
| 861 | lldb::offset_t offset = 0; |
| 862 | Value tmp; |
| 863 | uint32_t reg_num; |
| 864 | |
| 865 | /// Insertion point for evaluating multi-piece expression. |
| 866 | uint64_t op_piece_offset = 0; |
| 867 | Value pieces; // Used for DW_OP_piece |
| 868 | |
| 869 | Log *log = GetLog(LLDBLog::Expressions); |
| 870 | // A generic type is "an integral type that has the size of an address and an |
| 871 | // unspecified signedness". For now, just use the signedness of the operand. |
| 872 | // TODO: Implement a real typed stack, and store the genericness of the value |
| 873 | // there. |
| 874 | auto to_generic = [&](auto v) { |
| 875 | bool is_signed = std::is_signed<decltype(v)>::value; |
| 876 | return Scalar(llvm::APSInt( |
| 877 | llvm::APInt(8 * opcodes.GetAddressByteSize(), v, is_signed), |
| 878 | !is_signed)); |
| 879 | }; |
| 880 | |
| 881 | // The default kind is a memory location. This is updated by any |
| 882 | // operation that changes this, such as DW_OP_stack_value, and reset |
| 883 | // by composition operations like DW_OP_piece. |
| 884 | LocationDescriptionKind dwarf4_location_description_kind = Memory; |
| 885 | |
| 886 | while (opcodes.ValidOffset(offset)) { |
| 887 | const lldb::offset_t op_offset = offset; |
| 888 | const uint8_t op = opcodes.GetU8(&offset); |
| 889 | |
| 890 | if (log && log->GetVerbose()) { |
| 891 | size_t count = stack.size(); |
| 892 | LLDB_LOGF(log, "Stack before operation has %" PRIu64 " values:",do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack before operation has %" "l" "u" " values:", (uint64_t)count); } while (0) |
| 893 | (uint64_t)count)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack before operation has %" "l" "u" " values:", (uint64_t)count); } while (0); |
| 894 | for (size_t i = 0; i < count; ++i) { |
| 895 | StreamString new_value; |
| 896 | new_value.Printf("[%" PRIu64"l" "u" "]", (uint64_t)i); |
| 897 | stack[i].Dump(&new_value); |
| 898 | 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); |
| 899 | } |
| 900 | LLDB_LOGF(log, "0x%8.8" PRIx64 ": %s", op_offset,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("0x%8.8" "l" "x" ": %s", op_offset, DW_OP_value_to_name (op)); } while (0) |
| 901 | DW_OP_value_to_name(op))do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("0x%8.8" "l" "x" ": %s", op_offset, DW_OP_value_to_name (op)); } while (0); |
| 902 | } |
| 903 | |
| 904 | switch (op) { |
| 905 | // The DW_OP_addr operation has a single operand that encodes a machine |
| 906 | // address and whose size is the size of an address on the target machine. |
| 907 | case DW_OP_addr: |
| 908 | stack.push_back(Scalar(opcodes.GetAddress(&offset))); |
| 909 | stack.back().SetValueType(Value::ValueType::FileAddress); |
| 910 | // Convert the file address to a load address, so subsequent |
| 911 | // DWARF operators can operate on it. |
| 912 | if (frame) |
| 913 | stack.back().ConvertToLoadAddress(module_sp.get(), |
| 914 | frame->CalculateTarget().get()); |
| 915 | break; |
| 916 | |
| 917 | // The DW_OP_addr_sect_offset4 is used for any location expressions in |
| 918 | // shared libraries that have a location like: |
| 919 | // DW_OP_addr(0x1000) |
| 920 | // If this address resides in a shared library, then this virtual address |
| 921 | // won't make sense when it is evaluated in the context of a running |
| 922 | // process where shared libraries have been slid. To account for this, this |
| 923 | // new address type where we can store the section pointer and a 4 byte |
| 924 | // offset. |
| 925 | // case DW_OP_addr_sect_offset4: |
| 926 | // { |
| 927 | // result_type = eResultTypeFileAddress; |
| 928 | // lldb::Section *sect = (lldb::Section |
| 929 | // *)opcodes.GetMaxU64(&offset, sizeof(void *)); |
| 930 | // lldb::addr_t sect_offset = opcodes.GetU32(&offset); |
| 931 | // |
| 932 | // Address so_addr (sect, sect_offset); |
| 933 | // lldb::addr_t load_addr = so_addr.GetLoadAddress(); |
| 934 | // if (load_addr != LLDB_INVALID_ADDRESS) |
| 935 | // { |
| 936 | // // We successfully resolve a file address to a load |
| 937 | // // address. |
| 938 | // stack.push_back(load_addr); |
| 939 | // break; |
| 940 | // } |
| 941 | // else |
| 942 | // { |
| 943 | // // We were able |
| 944 | // if (error_ptr) |
| 945 | // error_ptr->SetErrorStringWithFormat ("Section %s in |
| 946 | // %s is not currently loaded.\n", |
| 947 | // sect->GetName().AsCString(), |
| 948 | // sect->GetModule()->GetFileSpec().GetFilename().AsCString()); |
| 949 | // return false; |
| 950 | // } |
| 951 | // } |
| 952 | // break; |
| 953 | |
| 954 | // OPCODE: DW_OP_deref |
| 955 | // OPERANDS: none |
| 956 | // DESCRIPTION: Pops the top stack entry and treats it as an address. |
| 957 | // The value retrieved from that address is pushed. The size of the data |
| 958 | // retrieved from the dereferenced address is the size of an address on the |
| 959 | // target machine. |
| 960 | case DW_OP_deref: { |
| 961 | if (stack.empty()) { |
| 962 | if (error_ptr) |
| 963 | error_ptr->SetErrorString("Expression stack empty for DW_OP_deref."); |
| 964 | return false; |
| 965 | } |
| 966 | Value::ValueType value_type = stack.back().GetValueType(); |
| 967 | switch (value_type) { |
| 968 | case Value::ValueType::HostAddress: { |
| 969 | void *src = (void *)stack.back().GetScalar().ULongLong(); |
| 970 | intptr_t ptr; |
| 971 | ::memcpy(&ptr, src, sizeof(void *)); |
| 972 | stack.back().GetScalar() = ptr; |
| 973 | stack.back().ClearContext(); |
| 974 | } break; |
| 975 | case Value::ValueType::FileAddress: { |
| 976 | auto file_addr = stack.back().GetScalar().ULongLong( |
| 977 | LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
| 978 | |
| 979 | Address so_addr; |
| 980 | auto maybe_load_addr = ResolveLoadAddress( |
| 981 | exe_ctx, module_sp, error_ptr, "DW_OP_deref", file_addr, so_addr); |
| 982 | |
| 983 | if (!maybe_load_addr) |
| 984 | return false; |
| 985 | |
| 986 | stack.back().GetScalar() = *maybe_load_addr; |
| 987 | // Fall through to load address promotion code below. |
| 988 | } |
| 989 | [[fallthrough]]; |
| 990 | case Value::ValueType::Scalar: |
| 991 | // Promote Scalar to LoadAddress and fall through. |
| 992 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
| 993 | [[fallthrough]]; |
| 994 | case Value::ValueType::LoadAddress: |
| 995 | if (exe_ctx) { |
| 996 | if (process) { |
| 997 | lldb::addr_t pointer_addr = |
| 998 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
| 999 | Status error; |
| 1000 | lldb::addr_t pointer_value = |
| 1001 | process->ReadPointerFromMemory(pointer_addr, error); |
| 1002 | if (pointer_value != LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
| 1003 | if (ABISP abi_sp = process->GetABI()) |
| 1004 | pointer_value = abi_sp->FixCodeAddress(pointer_value); |
| 1005 | stack.back().GetScalar() = pointer_value; |
| 1006 | stack.back().ClearContext(); |
| 1007 | } else { |
| 1008 | if (error_ptr) |
| 1009 | error_ptr->SetErrorStringWithFormat( |
| 1010 | "Failed to dereference pointer from 0x%" PRIx64"l" "x" |
| 1011 | " for DW_OP_deref: %s\n", |
| 1012 | pointer_addr, error.AsCString()); |
| 1013 | return false; |
| 1014 | } |
| 1015 | } else { |
| 1016 | if (error_ptr) |
| 1017 | error_ptr->SetErrorString("NULL process for DW_OP_deref.\n"); |
| 1018 | return false; |
| 1019 | } |
| 1020 | } else { |
| 1021 | if (error_ptr) |
| 1022 | error_ptr->SetErrorString( |
| 1023 | "NULL execution context for DW_OP_deref.\n"); |
| 1024 | return false; |
| 1025 | } |
| 1026 | break; |
| 1027 | |
| 1028 | case Value::ValueType::Invalid: |
| 1029 | if (error_ptr) |
| 1030 | error_ptr->SetErrorString("Invalid value type for DW_OP_deref.\n"); |
| 1031 | return false; |
| 1032 | } |
| 1033 | |
| 1034 | } break; |
| 1035 | |
| 1036 | // OPCODE: DW_OP_deref_size |
| 1037 | // OPERANDS: 1 |
| 1038 | // 1 - uint8_t that specifies the size of the data to dereference. |
| 1039 | // DESCRIPTION: Behaves like the DW_OP_deref operation: it pops the top |
| 1040 | // stack entry and treats it as an address. The value retrieved from that |
| 1041 | // address is pushed. In the DW_OP_deref_size operation, however, the size |
| 1042 | // in bytes of the data retrieved from the dereferenced address is |
| 1043 | // specified by the single operand. This operand is a 1-byte unsigned |
| 1044 | // integral constant whose value may not be larger than the size of an |
| 1045 | // address on the target machine. The data retrieved is zero extended to |
| 1046 | // the size of an address on the target machine before being pushed on the |
| 1047 | // expression stack. |
| 1048 | case DW_OP_deref_size: { |
| 1049 | if (stack.empty()) { |
| 1050 | if (error_ptr) |
| 1051 | error_ptr->SetErrorString( |
| 1052 | "Expression stack empty for DW_OP_deref_size."); |
| 1053 | return false; |
| 1054 | } |
| 1055 | uint8_t size = opcodes.GetU8(&offset); |
| 1056 | Value::ValueType value_type = stack.back().GetValueType(); |
| 1057 | switch (value_type) { |
| 1058 | case Value::ValueType::HostAddress: { |
| 1059 | void *src = (void *)stack.back().GetScalar().ULongLong(); |
| 1060 | intptr_t ptr; |
| 1061 | ::memcpy(&ptr, src, sizeof(void *)); |
| 1062 | // I can't decide whether the size operand should apply to the bytes in |
| 1063 | // their |
| 1064 | // lldb-host endianness or the target endianness.. I doubt this'll ever |
| 1065 | // come up but I'll opt for assuming big endian regardless. |
| 1066 | switch (size) { |
| 1067 | case 1: |
| 1068 | ptr = ptr & 0xff; |
| 1069 | break; |
| 1070 | case 2: |
| 1071 | ptr = ptr & 0xffff; |
| 1072 | break; |
| 1073 | case 3: |
| 1074 | ptr = ptr & 0xffffff; |
| 1075 | break; |
| 1076 | case 4: |
| 1077 | ptr = ptr & 0xffffffff; |
| 1078 | break; |
| 1079 | // the casts are added to work around the case where intptr_t is a 32 |
| 1080 | // bit quantity; |
| 1081 | // presumably we won't hit the 5..7 cases if (void*) is 32-bits in this |
| 1082 | // program. |
| 1083 | case 5: |
| 1084 | ptr = (intptr_t)ptr & 0xffffffffffULL; |
| 1085 | break; |
| 1086 | case 6: |
| 1087 | ptr = (intptr_t)ptr & 0xffffffffffffULL; |
| 1088 | break; |
| 1089 | case 7: |
| 1090 | ptr = (intptr_t)ptr & 0xffffffffffffffULL; |
| 1091 | break; |
| 1092 | default: |
| 1093 | break; |
| 1094 | } |
| 1095 | stack.back().GetScalar() = ptr; |
| 1096 | stack.back().ClearContext(); |
| 1097 | } break; |
| 1098 | case Value::ValueType::FileAddress: { |
| 1099 | auto file_addr = |
| 1100 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
| 1101 | Address so_addr; |
| 1102 | auto maybe_load_addr = |
| 1103 | ResolveLoadAddress(exe_ctx, module_sp, error_ptr, |
| 1104 | "DW_OP_deref_size", file_addr, so_addr, |
| 1105 | /*check_sectionoffset=*/true); |
| 1106 | |
| 1107 | if (!maybe_load_addr) |
| 1108 | return false; |
| 1109 | |
| 1110 | addr_t load_addr = *maybe_load_addr; |
| 1111 | |
| 1112 | if (load_addr == LLDB_INVALID_ADDRESS(18446744073709551615UL) && so_addr.IsSectionOffset()) { |
| 1113 | uint8_t addr_bytes[8]; |
| 1114 | Status error; |
| 1115 | |
| 1116 | if (exe_ctx->GetTargetRef().ReadMemory( |
| 1117 | so_addr, &addr_bytes, size, error, |
| 1118 | /*force_live_memory=*/false) == size) { |
| 1119 | ObjectFile *objfile = module_sp->GetObjectFile(); |
| 1120 | |
| 1121 | stack.back().GetScalar() = DerefSizeExtractDataHelper( |
| 1122 | addr_bytes, size, objfile->GetByteOrder(), size); |
| 1123 | stack.back().ClearContext(); |
| 1124 | break; |
| 1125 | } else { |
| 1126 | if (error_ptr) |
| 1127 | error_ptr->SetErrorStringWithFormat( |
| 1128 | "Failed to dereference pointer for for DW_OP_deref_size: " |
| 1129 | "%s\n", |
| 1130 | error.AsCString()); |
| 1131 | return false; |
| 1132 | } |
| 1133 | } |
| 1134 | stack.back().GetScalar() = load_addr; |
| 1135 | // Fall through to load address promotion code below. |
| 1136 | } |
| 1137 | |
| 1138 | [[fallthrough]]; |
| 1139 | case Value::ValueType::Scalar: |
| 1140 | case Value::ValueType::LoadAddress: |
| 1141 | if (exe_ctx) { |
| 1142 | if (process) { |
| 1143 | lldb::addr_t pointer_addr = |
| 1144 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
| 1145 | uint8_t addr_bytes[sizeof(lldb::addr_t)]; |
| 1146 | Status error; |
| 1147 | if (process->ReadMemory(pointer_addr, &addr_bytes, size, error) == |
| 1148 | size) { |
| 1149 | |
| 1150 | stack.back().GetScalar() = |
| 1151 | DerefSizeExtractDataHelper(addr_bytes, sizeof(addr_bytes), |
| 1152 | process->GetByteOrder(), size); |
| 1153 | stack.back().ClearContext(); |
| 1154 | } else { |
| 1155 | if (error_ptr) |
| 1156 | error_ptr->SetErrorStringWithFormat( |
| 1157 | "Failed to dereference pointer from 0x%" PRIx64"l" "x" |
| 1158 | " for DW_OP_deref: %s\n", |
| 1159 | pointer_addr, error.AsCString()); |
| 1160 | return false; |
| 1161 | } |
| 1162 | } else { |
| 1163 | if (error_ptr) |
| 1164 | error_ptr->SetErrorString("NULL process for DW_OP_deref_size.\n"); |
| 1165 | return false; |
| 1166 | } |
| 1167 | } else { |
| 1168 | if (error_ptr) |
| 1169 | error_ptr->SetErrorString( |
| 1170 | "NULL execution context for DW_OP_deref_size.\n"); |
| 1171 | return false; |
| 1172 | } |
| 1173 | break; |
| 1174 | |
| 1175 | case Value::ValueType::Invalid: |
| 1176 | if (error_ptr) |
| 1177 | error_ptr->SetErrorString("Invalid value for DW_OP_deref_size.\n"); |
| 1178 | return false; |
| 1179 | } |
| 1180 | |
| 1181 | } break; |
| 1182 | |
| 1183 | // OPCODE: DW_OP_xderef_size |
| 1184 | // OPERANDS: 1 |
| 1185 | // 1 - uint8_t that specifies the size of the data to dereference. |
| 1186 | // DESCRIPTION: Behaves like the DW_OP_xderef operation: the entry at |
| 1187 | // the top of the stack is treated as an address. The second stack entry is |
| 1188 | // treated as an "address space identifier" for those architectures that |
| 1189 | // support multiple address spaces. The top two stack elements are popped, |
| 1190 | // a data item is retrieved through an implementation-defined address |
| 1191 | // calculation and pushed as the new stack top. In the DW_OP_xderef_size |
| 1192 | // operation, however, the size in bytes of the data retrieved from the |
| 1193 | // dereferenced address is specified by the single operand. This operand is |
| 1194 | // a 1-byte unsigned integral constant whose value may not be larger than |
| 1195 | // the size of an address on the target machine. The data retrieved is zero |
| 1196 | // extended to the size of an address on the target machine before being |
| 1197 | // pushed on the expression stack. |
| 1198 | case DW_OP_xderef_size: |
| 1199 | if (error_ptr) |
| 1200 | error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef_size."); |
| 1201 | return false; |
| 1202 | // OPCODE: DW_OP_xderef |
| 1203 | // OPERANDS: none |
| 1204 | // DESCRIPTION: Provides an extended dereference mechanism. The entry at |
| 1205 | // the top of the stack is treated as an address. The second stack entry is |
| 1206 | // treated as an "address space identifier" for those architectures that |
| 1207 | // support multiple address spaces. The top two stack elements are popped, |
| 1208 | // a data item is retrieved through an implementation-defined address |
| 1209 | // calculation and pushed as the new stack top. The size of the data |
| 1210 | // retrieved from the dereferenced address is the size of an address on the |
| 1211 | // target machine. |
| 1212 | case DW_OP_xderef: |
| 1213 | if (error_ptr) |
| 1214 | error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef."); |
| 1215 | return false; |
| 1216 | |
| 1217 | // All DW_OP_constXXX opcodes have a single operand as noted below: |
| 1218 | // |
| 1219 | // Opcode Operand 1 |
| 1220 | // DW_OP_const1u 1-byte unsigned integer constant |
| 1221 | // DW_OP_const1s 1-byte signed integer constant |
| 1222 | // DW_OP_const2u 2-byte unsigned integer constant |
| 1223 | // DW_OP_const2s 2-byte signed integer constant |
| 1224 | // DW_OP_const4u 4-byte unsigned integer constant |
| 1225 | // DW_OP_const4s 4-byte signed integer constant |
| 1226 | // DW_OP_const8u 8-byte unsigned integer constant |
| 1227 | // DW_OP_const8s 8-byte signed integer constant |
| 1228 | // DW_OP_constu unsigned LEB128 integer constant |
| 1229 | // DW_OP_consts signed LEB128 integer constant |
| 1230 | case DW_OP_const1u: |
| 1231 | stack.push_back(to_generic(opcodes.GetU8(&offset))); |
| 1232 | break; |
| 1233 | case DW_OP_const1s: |
| 1234 | stack.push_back(to_generic((int8_t)opcodes.GetU8(&offset))); |
| 1235 | break; |
| 1236 | case DW_OP_const2u: |
| 1237 | stack.push_back(to_generic(opcodes.GetU16(&offset))); |
| 1238 | break; |
| 1239 | case DW_OP_const2s: |
| 1240 | stack.push_back(to_generic((int16_t)opcodes.GetU16(&offset))); |
| 1241 | break; |
| 1242 | case DW_OP_const4u: |
| 1243 | stack.push_back(to_generic(opcodes.GetU32(&offset))); |
| 1244 | break; |
| 1245 | case DW_OP_const4s: |
| 1246 | stack.push_back(to_generic((int32_t)opcodes.GetU32(&offset))); |
| 1247 | break; |
| 1248 | case DW_OP_const8u: |
| 1249 | stack.push_back(to_generic(opcodes.GetU64(&offset))); |
| 1250 | break; |
| 1251 | case DW_OP_const8s: |
| 1252 | stack.push_back(to_generic((int64_t)opcodes.GetU64(&offset))); |
| 1253 | break; |
| 1254 | // These should also use to_generic, but we can't do that due to a |
| 1255 | // producer-side bug in llvm. See llvm.org/pr48087. |
| 1256 | case DW_OP_constu: |
| 1257 | stack.push_back(Scalar(opcodes.GetULEB128(&offset))); |
| 1258 | break; |
| 1259 | case DW_OP_consts: |
| 1260 | stack.push_back(Scalar(opcodes.GetSLEB128(&offset))); |
| 1261 | break; |
| 1262 | |
| 1263 | // OPCODE: DW_OP_dup |
| 1264 | // OPERANDS: none |
| 1265 | // DESCRIPTION: duplicates the value at the top of the stack |
| 1266 | case DW_OP_dup: |
| 1267 | if (stack.empty()) { |
| 1268 | if (error_ptr) |
| 1269 | error_ptr->SetErrorString("Expression stack empty for DW_OP_dup."); |
| 1270 | return false; |
| 1271 | } else |
| 1272 | stack.push_back(stack.back()); |
| 1273 | break; |
| 1274 | |
| 1275 | // OPCODE: DW_OP_drop |
| 1276 | // OPERANDS: none |
| 1277 | // DESCRIPTION: pops the value at the top of the stack |
| 1278 | case DW_OP_drop: |
| 1279 | if (stack.empty()) { |
| 1280 | if (error_ptr) |
| 1281 | error_ptr->SetErrorString("Expression stack empty for DW_OP_drop."); |
| 1282 | return false; |
| 1283 | } else |
| 1284 | stack.pop_back(); |
| 1285 | break; |
| 1286 | |
| 1287 | // OPCODE: DW_OP_over |
| 1288 | // OPERANDS: none |
| 1289 | // DESCRIPTION: Duplicates the entry currently second in the stack at |
| 1290 | // the top of the stack. |
| 1291 | case DW_OP_over: |
| 1292 | if (stack.size() < 2) { |
| 1293 | if (error_ptr) |
| 1294 | error_ptr->SetErrorString( |
| 1295 | "Expression stack needs at least 2 items for DW_OP_over."); |
| 1296 | return false; |
| 1297 | } else |
| 1298 | stack.push_back(stack[stack.size() - 2]); |
| 1299 | break; |
| 1300 | |
| 1301 | // OPCODE: DW_OP_pick |
| 1302 | // OPERANDS: uint8_t index into the current stack |
| 1303 | // DESCRIPTION: The stack entry with the specified index (0 through 255, |
| 1304 | // inclusive) is pushed on the stack |
| 1305 | case DW_OP_pick: { |
| 1306 | uint8_t pick_idx = opcodes.GetU8(&offset); |
| 1307 | if (pick_idx < stack.size()) |
| 1308 | stack.push_back(stack[stack.size() - 1 - pick_idx]); |
| 1309 | else { |
| 1310 | if (error_ptr) |
| 1311 | error_ptr->SetErrorStringWithFormat( |
| 1312 | "Index %u out of range for DW_OP_pick.\n", pick_idx); |
| 1313 | return false; |
| 1314 | } |
| 1315 | } break; |
| 1316 | |
| 1317 | // OPCODE: DW_OP_swap |
| 1318 | // OPERANDS: none |
| 1319 | // DESCRIPTION: swaps the top two stack entries. The entry at the top |
| 1320 | // of the stack becomes the second stack entry, and the second entry |
| 1321 | // becomes the top of the stack |
| 1322 | case DW_OP_swap: |
| 1323 | if (stack.size() < 2) { |
| 1324 | if (error_ptr) |
| 1325 | error_ptr->SetErrorString( |
| 1326 | "Expression stack needs at least 2 items for DW_OP_swap."); |
| 1327 | return false; |
| 1328 | } else { |
| 1329 | tmp = stack.back(); |
| 1330 | stack.back() = stack[stack.size() - 2]; |
| 1331 | stack[stack.size() - 2] = tmp; |
| 1332 | } |
| 1333 | break; |
| 1334 | |
| 1335 | // OPCODE: DW_OP_rot |
| 1336 | // OPERANDS: none |
| 1337 | // DESCRIPTION: Rotates the first three stack entries. The entry at |
| 1338 | // the top of the stack becomes the third stack entry, the second entry |
| 1339 | // becomes the top of the stack, and the third entry becomes the second |
| 1340 | // entry. |
| 1341 | case DW_OP_rot: |
| 1342 | if (stack.size() < 3) { |
| 1343 | if (error_ptr) |
| 1344 | error_ptr->SetErrorString( |
| 1345 | "Expression stack needs at least 3 items for DW_OP_rot."); |
| 1346 | return false; |
| 1347 | } else { |
| 1348 | size_t last_idx = stack.size() - 1; |
| 1349 | Value old_top = stack[last_idx]; |
| 1350 | stack[last_idx] = stack[last_idx - 1]; |
| 1351 | stack[last_idx - 1] = stack[last_idx - 2]; |
| 1352 | stack[last_idx - 2] = old_top; |
| 1353 | } |
| 1354 | break; |
| 1355 | |
| 1356 | // OPCODE: DW_OP_abs |
| 1357 | // OPERANDS: none |
| 1358 | // DESCRIPTION: pops the top stack entry, interprets it as a signed |
| 1359 | // value and pushes its absolute value. If the absolute value can not be |
| 1360 | // represented, the result is undefined. |
| 1361 | case DW_OP_abs: |
| 1362 | if (stack.empty()) { |
| 1363 | if (error_ptr) |
| 1364 | error_ptr->SetErrorString( |
| 1365 | "Expression stack needs at least 1 item for DW_OP_abs."); |
| 1366 | return false; |
| 1367 | } else if (!stack.back().ResolveValue(exe_ctx).AbsoluteValue()) { |
| 1368 | if (error_ptr) |
| 1369 | error_ptr->SetErrorString( |
| 1370 | "Failed to take the absolute value of the first stack item."); |
| 1371 | return false; |
| 1372 | } |
| 1373 | break; |
| 1374 | |
| 1375 | // OPCODE: DW_OP_and |
| 1376 | // OPERANDS: none |
| 1377 | // DESCRIPTION: pops the top two stack values, performs a bitwise and |
| 1378 | // operation on the two, and pushes the result. |
| 1379 | case DW_OP_and: |
| 1380 | if (stack.size() < 2) { |
| 1381 | if (error_ptr) |
| 1382 | error_ptr->SetErrorString( |
| 1383 | "Expression stack needs at least 2 items for DW_OP_and."); |
| 1384 | return false; |
| 1385 | } else { |
| 1386 | tmp = stack.back(); |
| 1387 | stack.pop_back(); |
| 1388 | stack.back().ResolveValue(exe_ctx) = |
| 1389 | stack.back().ResolveValue(exe_ctx) & tmp.ResolveValue(exe_ctx); |
| 1390 | } |
| 1391 | break; |
| 1392 | |
| 1393 | // OPCODE: DW_OP_div |
| 1394 | // OPERANDS: none |
| 1395 | // DESCRIPTION: pops the top two stack values, divides the former second |
| 1396 | // entry by the former top of the stack using signed division, and pushes |
| 1397 | // the result. |
| 1398 | case DW_OP_div: |
| 1399 | if (stack.size() < 2) { |
| 1400 | if (error_ptr) |
| 1401 | error_ptr->SetErrorString( |
| 1402 | "Expression stack needs at least 2 items for DW_OP_div."); |
| 1403 | return false; |
| 1404 | } else { |
| 1405 | tmp = stack.back(); |
| 1406 | if (tmp.ResolveValue(exe_ctx).IsZero()) { |
| 1407 | if (error_ptr) |
| 1408 | error_ptr->SetErrorString("Divide by zero."); |
| 1409 | return false; |
| 1410 | } else { |
| 1411 | stack.pop_back(); |
| 1412 | stack.back() = |
| 1413 | stack.back().ResolveValue(exe_ctx) / tmp.ResolveValue(exe_ctx); |
| 1414 | if (!stack.back().ResolveValue(exe_ctx).IsValid()) { |
| 1415 | if (error_ptr) |
| 1416 | error_ptr->SetErrorString("Divide failed."); |
| 1417 | return false; |
| 1418 | } |
| 1419 | } |
| 1420 | } |
| 1421 | break; |
| 1422 | |
| 1423 | // OPCODE: DW_OP_minus |
| 1424 | // OPERANDS: none |
| 1425 | // DESCRIPTION: pops the top two stack values, subtracts the former top |
| 1426 | // of the stack from the former second entry, and pushes the result. |
| 1427 | case DW_OP_minus: |
| 1428 | if (stack.size() < 2) { |
| 1429 | if (error_ptr) |
| 1430 | error_ptr->SetErrorString( |
| 1431 | "Expression stack needs at least 2 items for DW_OP_minus."); |
| 1432 | return false; |
| 1433 | } else { |
| 1434 | tmp = stack.back(); |
| 1435 | stack.pop_back(); |
| 1436 | stack.back().ResolveValue(exe_ctx) = |
| 1437 | stack.back().ResolveValue(exe_ctx) - tmp.ResolveValue(exe_ctx); |
| 1438 | } |
| 1439 | break; |
| 1440 | |
| 1441 | // OPCODE: DW_OP_mod |
| 1442 | // OPERANDS: none |
| 1443 | // DESCRIPTION: pops the top two stack values and pushes the result of |
| 1444 | // the calculation: former second stack entry modulo the former top of the |
| 1445 | // stack. |
| 1446 | case DW_OP_mod: |
| 1447 | if (stack.size() < 2) { |
| 1448 | if (error_ptr) |
| 1449 | error_ptr->SetErrorString( |
| 1450 | "Expression stack needs at least 2 items for DW_OP_mod."); |
| 1451 | return false; |
| 1452 | } else { |
| 1453 | tmp = stack.back(); |
| 1454 | stack.pop_back(); |
| 1455 | stack.back().ResolveValue(exe_ctx) = |
| 1456 | stack.back().ResolveValue(exe_ctx) % tmp.ResolveValue(exe_ctx); |
| 1457 | } |
| 1458 | break; |
| 1459 | |
| 1460 | // OPCODE: DW_OP_mul |
| 1461 | // OPERANDS: none |
| 1462 | // DESCRIPTION: pops the top two stack entries, multiplies them |
| 1463 | // together, and pushes the result. |
| 1464 | case DW_OP_mul: |
| 1465 | if (stack.size() < 2) { |
| 1466 | if (error_ptr) |
| 1467 | error_ptr->SetErrorString( |
| 1468 | "Expression stack needs at least 2 items for DW_OP_mul."); |
| 1469 | return false; |
| 1470 | } else { |
| 1471 | tmp = stack.back(); |
| 1472 | stack.pop_back(); |
| 1473 | stack.back().ResolveValue(exe_ctx) = |
| 1474 | stack.back().ResolveValue(exe_ctx) * tmp.ResolveValue(exe_ctx); |
| 1475 | } |
| 1476 | break; |
| 1477 | |
| 1478 | // OPCODE: DW_OP_neg |
| 1479 | // OPERANDS: none |
| 1480 | // DESCRIPTION: pops the top stack entry, and pushes its negation. |
| 1481 | case DW_OP_neg: |
| 1482 | if (stack.empty()) { |
| 1483 | if (error_ptr) |
| 1484 | error_ptr->SetErrorString( |
| 1485 | "Expression stack needs at least 1 item for DW_OP_neg."); |
| 1486 | return false; |
| 1487 | } else { |
| 1488 | if (!stack.back().ResolveValue(exe_ctx).UnaryNegate()) { |
| 1489 | if (error_ptr) |
| 1490 | error_ptr->SetErrorString("Unary negate failed."); |
| 1491 | return false; |
| 1492 | } |
| 1493 | } |
| 1494 | break; |
| 1495 | |
| 1496 | // OPCODE: DW_OP_not |
| 1497 | // OPERANDS: none |
| 1498 | // DESCRIPTION: pops the top stack entry, and pushes its bitwise |
| 1499 | // complement |
| 1500 | case DW_OP_not: |
| 1501 | if (stack.empty()) { |
| 1502 | if (error_ptr) |
| 1503 | error_ptr->SetErrorString( |
| 1504 | "Expression stack needs at least 1 item for DW_OP_not."); |
| 1505 | return false; |
| 1506 | } else { |
| 1507 | if (!stack.back().ResolveValue(exe_ctx).OnesComplement()) { |
| 1508 | if (error_ptr) |
| 1509 | error_ptr->SetErrorString("Logical NOT failed."); |
| 1510 | return false; |
| 1511 | } |
| 1512 | } |
| 1513 | break; |
| 1514 | |
| 1515 | // OPCODE: DW_OP_or |
| 1516 | // OPERANDS: none |
| 1517 | // DESCRIPTION: pops the top two stack entries, performs a bitwise or |
| 1518 | // operation on the two, and pushes the result. |
| 1519 | case DW_OP_or: |
| 1520 | if (stack.size() < 2) { |
| 1521 | if (error_ptr) |
| 1522 | error_ptr->SetErrorString( |
| 1523 | "Expression stack needs at least 2 items for DW_OP_or."); |
| 1524 | return false; |
| 1525 | } else { |
| 1526 | tmp = stack.back(); |
| 1527 | stack.pop_back(); |
| 1528 | stack.back().ResolveValue(exe_ctx) = |
| 1529 | stack.back().ResolveValue(exe_ctx) | tmp.ResolveValue(exe_ctx); |
| 1530 | } |
| 1531 | break; |
| 1532 | |
| 1533 | // OPCODE: DW_OP_plus |
| 1534 | // OPERANDS: none |
| 1535 | // DESCRIPTION: pops the top two stack entries, adds them together, and |
| 1536 | // pushes the result. |
| 1537 | case DW_OP_plus: |
| 1538 | if (stack.size() < 2) { |
| 1539 | if (error_ptr) |
| 1540 | error_ptr->SetErrorString( |
| 1541 | "Expression stack needs at least 2 items for DW_OP_plus."); |
| 1542 | return false; |
| 1543 | } else { |
| 1544 | tmp = stack.back(); |
| 1545 | stack.pop_back(); |
| 1546 | stack.back().GetScalar() += tmp.GetScalar(); |
| 1547 | } |
| 1548 | break; |
| 1549 | |
| 1550 | // OPCODE: DW_OP_plus_uconst |
| 1551 | // OPERANDS: none |
| 1552 | // DESCRIPTION: pops the top stack entry, adds it to the unsigned LEB128 |
| 1553 | // constant operand and pushes the result. |
| 1554 | case DW_OP_plus_uconst: |
| 1555 | if (stack.empty()) { |
| 1556 | if (error_ptr) |
| 1557 | error_ptr->SetErrorString( |
| 1558 | "Expression stack needs at least 1 item for DW_OP_plus_uconst."); |
| 1559 | return false; |
| 1560 | } else { |
| 1561 | const uint64_t uconst_value = opcodes.GetULEB128(&offset); |
| 1562 | // Implicit conversion from a UINT to a Scalar... |
| 1563 | stack.back().GetScalar() += uconst_value; |
| 1564 | if (!stack.back().GetScalar().IsValid()) { |
| 1565 | if (error_ptr) |
| 1566 | error_ptr->SetErrorString("DW_OP_plus_uconst failed."); |
| 1567 | return false; |
| 1568 | } |
| 1569 | } |
| 1570 | break; |
| 1571 | |
| 1572 | // OPCODE: DW_OP_shl |
| 1573 | // OPERANDS: none |
| 1574 | // DESCRIPTION: pops the top two stack entries, shifts the former |
| 1575 | // second entry left by the number of bits specified by the former top of |
| 1576 | // the stack, and pushes the result. |
| 1577 | case DW_OP_shl: |
| 1578 | if (stack.size() < 2) { |
| 1579 | if (error_ptr) |
| 1580 | error_ptr->SetErrorString( |
| 1581 | "Expression stack needs at least 2 items for DW_OP_shl."); |
| 1582 | return false; |
| 1583 | } else { |
| 1584 | tmp = stack.back(); |
| 1585 | stack.pop_back(); |
| 1586 | stack.back().ResolveValue(exe_ctx) <<= tmp.ResolveValue(exe_ctx); |
| 1587 | } |
| 1588 | break; |
| 1589 | |
| 1590 | // OPCODE: DW_OP_shr |
| 1591 | // OPERANDS: none |
| 1592 | // DESCRIPTION: pops the top two stack entries, shifts the former second |
| 1593 | // entry right logically (filling with zero bits) by the number of bits |
| 1594 | // specified by the former top of the stack, and pushes the result. |
| 1595 | case DW_OP_shr: |
| 1596 | if (stack.size() < 2) { |
| 1597 | if (error_ptr) |
| 1598 | error_ptr->SetErrorString( |
| 1599 | "Expression stack needs at least 2 items for DW_OP_shr."); |
| 1600 | return false; |
| 1601 | } else { |
| 1602 | tmp = stack.back(); |
| 1603 | stack.pop_back(); |
| 1604 | if (!stack.back().ResolveValue(exe_ctx).ShiftRightLogical( |
| 1605 | tmp.ResolveValue(exe_ctx))) { |
| 1606 | if (error_ptr) |
| 1607 | error_ptr->SetErrorString("DW_OP_shr failed."); |
| 1608 | return false; |
| 1609 | } |
| 1610 | } |
| 1611 | break; |
| 1612 | |
| 1613 | // OPCODE: DW_OP_shra |
| 1614 | // OPERANDS: none |
| 1615 | // DESCRIPTION: pops the top two stack entries, shifts the former second |
| 1616 | // entry right arithmetically (divide the magnitude by 2, keep the same |
| 1617 | // sign for the result) by the number of bits specified by the former top |
| 1618 | // of the stack, and pushes the result. |
| 1619 | case DW_OP_shra: |
| 1620 | if (stack.size() < 2) { |
| 1621 | if (error_ptr) |
| 1622 | error_ptr->SetErrorString( |
| 1623 | "Expression stack needs at least 2 items for DW_OP_shra."); |
| 1624 | return false; |
| 1625 | } else { |
| 1626 | tmp = stack.back(); |
| 1627 | stack.pop_back(); |
| 1628 | stack.back().ResolveValue(exe_ctx) >>= tmp.ResolveValue(exe_ctx); |
| 1629 | } |
| 1630 | break; |
| 1631 | |
| 1632 | // OPCODE: DW_OP_xor |
| 1633 | // OPERANDS: none |
| 1634 | // DESCRIPTION: pops the top two stack entries, performs the bitwise |
| 1635 | // exclusive-or operation on the two, and pushes the result. |
| 1636 | case DW_OP_xor: |
| 1637 | if (stack.size() < 2) { |
| 1638 | if (error_ptr) |
| 1639 | error_ptr->SetErrorString( |
| 1640 | "Expression stack needs at least 2 items for DW_OP_xor."); |
| 1641 | return false; |
| 1642 | } else { |
| 1643 | tmp = stack.back(); |
| 1644 | stack.pop_back(); |
| 1645 | stack.back().ResolveValue(exe_ctx) = |
| 1646 | stack.back().ResolveValue(exe_ctx) ^ tmp.ResolveValue(exe_ctx); |
| 1647 | } |
| 1648 | break; |
| 1649 | |
| 1650 | // OPCODE: DW_OP_skip |
| 1651 | // OPERANDS: int16_t |
| 1652 | // DESCRIPTION: An unconditional branch. Its single operand is a 2-byte |
| 1653 | // signed integer constant. The 2-byte constant is the number of bytes of |
| 1654 | // the DWARF expression to skip forward or backward from the current |
| 1655 | // operation, beginning after the 2-byte constant. |
| 1656 | case DW_OP_skip: { |
| 1657 | int16_t skip_offset = (int16_t)opcodes.GetU16(&offset); |
| 1658 | lldb::offset_t new_offset = offset + skip_offset; |
| 1659 | // New offset can point at the end of the data, in this case we should |
| 1660 | // terminate the DWARF expression evaluation (will happen in the loop |
| 1661 | // condition). |
| 1662 | if (new_offset <= opcodes.GetByteSize()) |
| 1663 | offset = new_offset; |
| 1664 | else { |
| 1665 | if (error_ptr) |
| 1666 | error_ptr->SetErrorStringWithFormatv( |
| 1667 | "Invalid opcode offset in DW_OP_skip: {0}+({1}) > {2}", offset, |
| 1668 | skip_offset, opcodes.GetByteSize()); |
| 1669 | return false; |
| 1670 | } |
| 1671 | } break; |
| 1672 | |
| 1673 | // OPCODE: DW_OP_bra |
| 1674 | // OPERANDS: int16_t |
| 1675 | // DESCRIPTION: A conditional branch. Its single operand is a 2-byte |
| 1676 | // signed integer constant. This operation pops the top of stack. If the |
| 1677 | // value popped is not the constant 0, the 2-byte constant operand is the |
| 1678 | // number of bytes of the DWARF expression to skip forward or backward from |
| 1679 | // the current operation, beginning after the 2-byte constant. |
| 1680 | case DW_OP_bra: |
| 1681 | if (stack.empty()) { |
| 1682 | if (error_ptr) |
| 1683 | error_ptr->SetErrorString( |
| 1684 | "Expression stack needs at least 1 item for DW_OP_bra."); |
| 1685 | return false; |
| 1686 | } else { |
| 1687 | tmp = stack.back(); |
| 1688 | stack.pop_back(); |
| 1689 | int16_t bra_offset = (int16_t)opcodes.GetU16(&offset); |
| 1690 | Scalar zero(0); |
| 1691 | if (tmp.ResolveValue(exe_ctx) != zero) { |
| 1692 | lldb::offset_t new_offset = offset + bra_offset; |
| 1693 | // New offset can point at the end of the data, in this case we should |
| 1694 | // terminate the DWARF expression evaluation (will happen in the loop |
| 1695 | // condition). |
| 1696 | if (new_offset <= opcodes.GetByteSize()) |
| 1697 | offset = new_offset; |
| 1698 | else { |
| 1699 | if (error_ptr) |
| 1700 | error_ptr->SetErrorStringWithFormatv( |
| 1701 | "Invalid opcode offset in DW_OP_bra: {0}+({1}) > {2}", offset, |
| 1702 | bra_offset, opcodes.GetByteSize()); |
| 1703 | return false; |
| 1704 | } |
| 1705 | } |
| 1706 | } |
| 1707 | break; |
| 1708 | |
| 1709 | // OPCODE: DW_OP_eq |
| 1710 | // OPERANDS: none |
| 1711 | // DESCRIPTION: pops the top two stack values, compares using the |
| 1712 | // equals (==) operator. |
| 1713 | // STACK RESULT: push the constant value 1 onto the stack if the result |
| 1714 | // of the operation is true or the constant value 0 if the result of the |
| 1715 | // operation is false. |
| 1716 | case DW_OP_eq: |
| 1717 | if (stack.size() < 2) { |
| 1718 | if (error_ptr) |
| 1719 | error_ptr->SetErrorString( |
| 1720 | "Expression stack needs at least 2 items for DW_OP_eq."); |
| 1721 | return false; |
| 1722 | } else { |
| 1723 | tmp = stack.back(); |
| 1724 | stack.pop_back(); |
| 1725 | stack.back().ResolveValue(exe_ctx) = |
| 1726 | stack.back().ResolveValue(exe_ctx) == tmp.ResolveValue(exe_ctx); |
| 1727 | } |
| 1728 | break; |
| 1729 | |
| 1730 | // OPCODE: DW_OP_ge |
| 1731 | // OPERANDS: none |
| 1732 | // DESCRIPTION: pops the top two stack values, compares using the |
| 1733 | // greater than or equal to (>=) operator. |
| 1734 | // STACK RESULT: push the constant value 1 onto the stack if the result |
| 1735 | // of the operation is true or the constant value 0 if the result of the |
| 1736 | // operation is false. |
| 1737 | case DW_OP_ge: |
| 1738 | if (stack.size() < 2) { |
| 1739 | if (error_ptr) |
| 1740 | error_ptr->SetErrorString( |
| 1741 | "Expression stack needs at least 2 items for DW_OP_ge."); |
| 1742 | return false; |
| 1743 | } else { |
| 1744 | tmp = stack.back(); |
| 1745 | stack.pop_back(); |
| 1746 | stack.back().ResolveValue(exe_ctx) = |
| 1747 | stack.back().ResolveValue(exe_ctx) >= tmp.ResolveValue(exe_ctx); |
| 1748 | } |
| 1749 | break; |
| 1750 | |
| 1751 | // OPCODE: DW_OP_gt |
| 1752 | // OPERANDS: none |
| 1753 | // DESCRIPTION: pops the top two stack values, compares using the |
| 1754 | // greater than (>) operator. |
| 1755 | // STACK RESULT: push the constant value 1 onto the stack if the result |
| 1756 | // of the operation is true or the constant value 0 if the result of the |
| 1757 | // operation is false. |
| 1758 | case DW_OP_gt: |
| 1759 | if (stack.size() < 2) { |
| 1760 | if (error_ptr) |
| 1761 | error_ptr->SetErrorString( |
| 1762 | "Expression stack needs at least 2 items for DW_OP_gt."); |
| 1763 | return false; |
| 1764 | } else { |
| 1765 | tmp = stack.back(); |
| 1766 | stack.pop_back(); |
| 1767 | stack.back().ResolveValue(exe_ctx) = |
| 1768 | stack.back().ResolveValue(exe_ctx) > tmp.ResolveValue(exe_ctx); |
| 1769 | } |
| 1770 | break; |
| 1771 | |
| 1772 | // OPCODE: DW_OP_le |
| 1773 | // OPERANDS: none |
| 1774 | // DESCRIPTION: pops the top two stack values, compares using the |
| 1775 | // less than or equal to (<=) operator. |
| 1776 | // STACK RESULT: push the constant value 1 onto the stack if the result |
| 1777 | // of the operation is true or the constant value 0 if the result of the |
| 1778 | // operation is false. |
| 1779 | case DW_OP_le: |
| 1780 | if (stack.size() < 2) { |
| 1781 | if (error_ptr) |
| 1782 | error_ptr->SetErrorString( |
| 1783 | "Expression stack needs at least 2 items for DW_OP_le."); |
| 1784 | return false; |
| 1785 | } else { |
| 1786 | tmp = stack.back(); |
| 1787 | stack.pop_back(); |
| 1788 | stack.back().ResolveValue(exe_ctx) = |
| 1789 | stack.back().ResolveValue(exe_ctx) <= tmp.ResolveValue(exe_ctx); |
| 1790 | } |
| 1791 | break; |
| 1792 | |
| 1793 | // OPCODE: DW_OP_lt |
| 1794 | // OPERANDS: none |
| 1795 | // DESCRIPTION: pops the top two stack values, compares using the |
| 1796 | // less than (<) operator. |
| 1797 | // STACK RESULT: push the constant value 1 onto the stack if the result |
| 1798 | // of the operation is true or the constant value 0 if the result of the |
| 1799 | // operation is false. |
| 1800 | case DW_OP_lt: |
| 1801 | if (stack.size() < 2) { |
| 1802 | if (error_ptr) |
| 1803 | error_ptr->SetErrorString( |
| 1804 | "Expression stack needs at least 2 items for DW_OP_lt."); |
| 1805 | return false; |
| 1806 | } else { |
| 1807 | tmp = stack.back(); |
| 1808 | stack.pop_back(); |
| 1809 | stack.back().ResolveValue(exe_ctx) = |
| 1810 | stack.back().ResolveValue(exe_ctx) < tmp.ResolveValue(exe_ctx); |
| 1811 | } |
| 1812 | break; |
| 1813 | |
| 1814 | // OPCODE: DW_OP_ne |
| 1815 | // OPERANDS: none |
| 1816 | // DESCRIPTION: pops the top two stack values, compares using the |
| 1817 | // not equal (!=) operator. |
| 1818 | // STACK RESULT: push the constant value 1 onto the stack if the result |
| 1819 | // of the operation is true or the constant value 0 if the result of the |
| 1820 | // operation is false. |
| 1821 | case DW_OP_ne: |
| 1822 | if (stack.size() < 2) { |
| 1823 | if (error_ptr) |
| 1824 | error_ptr->SetErrorString( |
| 1825 | "Expression stack needs at least 2 items for DW_OP_ne."); |
| 1826 | return false; |
| 1827 | } else { |
| 1828 | tmp = stack.back(); |
| 1829 | stack.pop_back(); |
| 1830 | stack.back().ResolveValue(exe_ctx) = |
| 1831 | stack.back().ResolveValue(exe_ctx) != tmp.ResolveValue(exe_ctx); |
| 1832 | } |
| 1833 | break; |
| 1834 | |
| 1835 | // OPCODE: DW_OP_litn |
| 1836 | // OPERANDS: none |
| 1837 | // DESCRIPTION: encode the unsigned literal values from 0 through 31. |
| 1838 | // STACK RESULT: push the unsigned literal constant value onto the top |
| 1839 | // of the stack. |
| 1840 | case DW_OP_lit0: |
| 1841 | case DW_OP_lit1: |
| 1842 | case DW_OP_lit2: |
| 1843 | case DW_OP_lit3: |
| 1844 | case DW_OP_lit4: |
| 1845 | case DW_OP_lit5: |
| 1846 | case DW_OP_lit6: |
| 1847 | case DW_OP_lit7: |
| 1848 | case DW_OP_lit8: |
| 1849 | case DW_OP_lit9: |
| 1850 | case DW_OP_lit10: |
| 1851 | case DW_OP_lit11: |
| 1852 | case DW_OP_lit12: |
| 1853 | case DW_OP_lit13: |
| 1854 | case DW_OP_lit14: |
| 1855 | case DW_OP_lit15: |
| 1856 | case DW_OP_lit16: |
| 1857 | case DW_OP_lit17: |
| 1858 | case DW_OP_lit18: |
| 1859 | case DW_OP_lit19: |
| 1860 | case DW_OP_lit20: |
| 1861 | case DW_OP_lit21: |
| 1862 | case DW_OP_lit22: |
| 1863 | case DW_OP_lit23: |
| 1864 | case DW_OP_lit24: |
| 1865 | case DW_OP_lit25: |
| 1866 | case DW_OP_lit26: |
| 1867 | case DW_OP_lit27: |
| 1868 | case DW_OP_lit28: |
| 1869 | case DW_OP_lit29: |
| 1870 | case DW_OP_lit30: |
| 1871 | case DW_OP_lit31: |
| 1872 | stack.push_back(to_generic(op - DW_OP_lit0)); |
| 1873 | break; |
| 1874 | |
| 1875 | // OPCODE: DW_OP_regN |
| 1876 | // OPERANDS: none |
| 1877 | // DESCRIPTION: Push the value in register n on the top of the stack. |
| 1878 | case DW_OP_reg0: |
| 1879 | case DW_OP_reg1: |
| 1880 | case DW_OP_reg2: |
| 1881 | case DW_OP_reg3: |
| 1882 | case DW_OP_reg4: |
| 1883 | case DW_OP_reg5: |
| 1884 | case DW_OP_reg6: |
| 1885 | case DW_OP_reg7: |
| 1886 | case DW_OP_reg8: |
| 1887 | case DW_OP_reg9: |
| 1888 | case DW_OP_reg10: |
| 1889 | case DW_OP_reg11: |
| 1890 | case DW_OP_reg12: |
| 1891 | case DW_OP_reg13: |
| 1892 | case DW_OP_reg14: |
| 1893 | case DW_OP_reg15: |
| 1894 | case DW_OP_reg16: |
| 1895 | case DW_OP_reg17: |
| 1896 | case DW_OP_reg18: |
| 1897 | case DW_OP_reg19: |
| 1898 | case DW_OP_reg20: |
| 1899 | case DW_OP_reg21: |
| 1900 | case DW_OP_reg22: |
| 1901 | case DW_OP_reg23: |
| 1902 | case DW_OP_reg24: |
| 1903 | case DW_OP_reg25: |
| 1904 | case DW_OP_reg26: |
| 1905 | case DW_OP_reg27: |
| 1906 | case DW_OP_reg28: |
| 1907 | case DW_OP_reg29: |
| 1908 | case DW_OP_reg30: |
| 1909 | case DW_OP_reg31: { |
| 1910 | dwarf4_location_description_kind = Register; |
| 1911 | reg_num = op - DW_OP_reg0; |
| 1912 | |
| 1913 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, tmp)) |
| 1914 | stack.push_back(tmp); |
| 1915 | else |
| 1916 | return false; |
| 1917 | } break; |
| 1918 | // OPCODE: DW_OP_regx |
| 1919 | // OPERANDS: |
| 1920 | // ULEB128 literal operand that encodes the register. |
| 1921 | // DESCRIPTION: Push the value in register on the top of the stack. |
| 1922 | case DW_OP_regx: { |
| 1923 | dwarf4_location_description_kind = Register; |
| 1924 | reg_num = opcodes.GetULEB128(&offset); |
| 1925 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, tmp)) |
| 1926 | stack.push_back(tmp); |
| 1927 | else |
| 1928 | return false; |
| 1929 | } break; |
| 1930 | |
| 1931 | // OPCODE: DW_OP_bregN |
| 1932 | // OPERANDS: |
| 1933 | // SLEB128 offset from register N |
| 1934 | // DESCRIPTION: Value is in memory at the address specified by register |
| 1935 | // N plus an offset. |
| 1936 | case DW_OP_breg0: |
| 1937 | case DW_OP_breg1: |
| 1938 | case DW_OP_breg2: |
| 1939 | case DW_OP_breg3: |
| 1940 | case DW_OP_breg4: |
| 1941 | case DW_OP_breg5: |
| 1942 | case DW_OP_breg6: |
| 1943 | case DW_OP_breg7: |
| 1944 | case DW_OP_breg8: |
| 1945 | case DW_OP_breg9: |
| 1946 | case DW_OP_breg10: |
| 1947 | case DW_OP_breg11: |
| 1948 | case DW_OP_breg12: |
| 1949 | case DW_OP_breg13: |
| 1950 | case DW_OP_breg14: |
| 1951 | case DW_OP_breg15: |
| 1952 | case DW_OP_breg16: |
| 1953 | case DW_OP_breg17: |
| 1954 | case DW_OP_breg18: |
| 1955 | case DW_OP_breg19: |
| 1956 | case DW_OP_breg20: |
| 1957 | case DW_OP_breg21: |
| 1958 | case DW_OP_breg22: |
| 1959 | case DW_OP_breg23: |
| 1960 | case DW_OP_breg24: |
| 1961 | case DW_OP_breg25: |
| 1962 | case DW_OP_breg26: |
| 1963 | case DW_OP_breg27: |
| 1964 | case DW_OP_breg28: |
| 1965 | case DW_OP_breg29: |
| 1966 | case DW_OP_breg30: |
| 1967 | case DW_OP_breg31: { |
| 1968 | reg_num = op - DW_OP_breg0; |
| 1969 | |
| 1970 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, |
| 1971 | tmp)) { |
| 1972 | int64_t breg_offset = opcodes.GetSLEB128(&offset); |
| 1973 | tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset; |
| 1974 | tmp.ClearContext(); |
| 1975 | stack.push_back(tmp); |
| 1976 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
| 1977 | } else |
| 1978 | return false; |
| 1979 | } break; |
| 1980 | // OPCODE: DW_OP_bregx |
| 1981 | // OPERANDS: 2 |
| 1982 | // ULEB128 literal operand that encodes the register. |
| 1983 | // SLEB128 offset from register N |
| 1984 | // DESCRIPTION: Value is in memory at the address specified by register |
| 1985 | // N plus an offset. |
| 1986 | case DW_OP_bregx: { |
| 1987 | reg_num = opcodes.GetULEB128(&offset); |
| 1988 | |
| 1989 | if (ReadRegisterValueAsScalar(reg_ctx, reg_kind, reg_num, error_ptr, |
| 1990 | tmp)) { |
| 1991 | int64_t breg_offset = opcodes.GetSLEB128(&offset); |
| 1992 | tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset; |
| 1993 | tmp.ClearContext(); |
| 1994 | stack.push_back(tmp); |
| 1995 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
| 1996 | } else |
| 1997 | return false; |
| 1998 | } break; |
| 1999 | |
| 2000 | case DW_OP_fbreg: |
| 2001 | if (exe_ctx) { |
| 2002 | if (frame) { |
| 2003 | Scalar value; |
| 2004 | if (frame->GetFrameBaseValue(value, error_ptr)) { |
| 2005 | int64_t fbreg_offset = opcodes.GetSLEB128(&offset); |
| 2006 | value += fbreg_offset; |
| 2007 | stack.push_back(value); |
| 2008 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
| 2009 | } else |
| 2010 | return false; |
| 2011 | } else { |
| 2012 | if (error_ptr) |
| 2013 | error_ptr->SetErrorString( |
| 2014 | "Invalid stack frame in context for DW_OP_fbreg opcode."); |
| 2015 | return false; |
| 2016 | } |
| 2017 | } else { |
| 2018 | if (error_ptr) |
| 2019 | error_ptr->SetErrorString( |
| 2020 | "NULL execution context for DW_OP_fbreg.\n"); |
| 2021 | return false; |
| 2022 | } |
| 2023 | |
| 2024 | break; |
| 2025 | |
| 2026 | // OPCODE: DW_OP_nop |
| 2027 | // OPERANDS: none |
| 2028 | // DESCRIPTION: A place holder. It has no effect on the location stack |
| 2029 | // or any of its values. |
| 2030 | case DW_OP_nop: |
| 2031 | break; |
| 2032 | |
| 2033 | // OPCODE: DW_OP_piece |
| 2034 | // OPERANDS: 1 |
| 2035 | // ULEB128: byte size of the piece |
| 2036 | // DESCRIPTION: The operand describes the size in bytes of the piece of |
| 2037 | // the object referenced by the DWARF expression whose result is at the top |
| 2038 | // of the stack. If the piece is located in a register, but does not occupy |
| 2039 | // the entire register, the placement of the piece within that register is |
| 2040 | // defined by the ABI. |
| 2041 | // |
| 2042 | // Many compilers store a single variable in sets of registers, or store a |
| 2043 | // variable partially in memory and partially in registers. DW_OP_piece |
| 2044 | // provides a way of describing how large a part of a variable a particular |
| 2045 | // DWARF expression refers to. |
| 2046 | case DW_OP_piece: { |
| 2047 | LocationDescriptionKind piece_locdesc = dwarf4_location_description_kind; |
| 2048 | // Reset for the next piece. |
| 2049 | dwarf4_location_description_kind = Memory; |
| 2050 | |
| 2051 | const uint64_t piece_byte_size = opcodes.GetULEB128(&offset); |
| 2052 | |
| 2053 | if (piece_byte_size > 0) { |
| 2054 | Value curr_piece; |
| 2055 | |
| 2056 | if (stack.empty()) { |
| 2057 | UpdateValueTypeFromLocationDescription( |
| 2058 | log, dwarf_cu, LocationDescriptionKind::Empty); |
| 2059 | // In a multi-piece expression, this means that the current piece is |
| 2060 | // not available. Fill with zeros for now by resizing the data and |
| 2061 | // appending it |
| 2062 | curr_piece.ResizeData(piece_byte_size); |
| 2063 | // Note that "0" is not a correct value for the unknown bits. |
| 2064 | // It would be better to also return a mask of valid bits together |
| 2065 | // with the expression result, so the debugger can print missing |
| 2066 | // members as "<optimized out>" or something. |
| 2067 | ::memset(curr_piece.GetBuffer().GetBytes(), 0, piece_byte_size); |
| 2068 | pieces.AppendDataToHostBuffer(curr_piece); |
| 2069 | } else { |
| 2070 | Status error; |
| 2071 | // Extract the current piece into "curr_piece" |
| 2072 | Value curr_piece_source_value(stack.back()); |
| 2073 | stack.pop_back(); |
| 2074 | UpdateValueTypeFromLocationDescription(log, dwarf_cu, piece_locdesc, |
| 2075 | &curr_piece_source_value); |
| 2076 | |
| 2077 | const Value::ValueType curr_piece_source_value_type = |
| 2078 | curr_piece_source_value.GetValueType(); |
| 2079 | switch (curr_piece_source_value_type) { |
| 2080 | case Value::ValueType::Invalid: |
| 2081 | return false; |
| 2082 | case Value::ValueType::LoadAddress: |
| 2083 | if (process) { |
| 2084 | if (curr_piece.ResizeData(piece_byte_size) == piece_byte_size) { |
| 2085 | lldb::addr_t load_addr = |
| 2086 | curr_piece_source_value.GetScalar().ULongLong( |
| 2087 | LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
| 2088 | if (process->ReadMemory( |
| 2089 | load_addr, curr_piece.GetBuffer().GetBytes(), |
| 2090 | piece_byte_size, error) != piece_byte_size) { |
| 2091 | if (error_ptr) |
| 2092 | error_ptr->SetErrorStringWithFormat( |
| 2093 | "failed to read memory DW_OP_piece(%" PRIu64"l" "u" |
| 2094 | ") from 0x%" PRIx64"l" "x", |
| 2095 | piece_byte_size, load_addr); |
| 2096 | return false; |
| 2097 | } |
| 2098 | } else { |
| 2099 | if (error_ptr) |
| 2100 | error_ptr->SetErrorStringWithFormat( |
| 2101 | "failed to resize the piece memory buffer for " |
| 2102 | "DW_OP_piece(%" PRIu64"l" "u" ")", |
| 2103 | piece_byte_size); |
| 2104 | return false; |
| 2105 | } |
| 2106 | } |
| 2107 | break; |
| 2108 | |
| 2109 | case Value::ValueType::FileAddress: |
| 2110 | case Value::ValueType::HostAddress: |
| 2111 | if (error_ptr) { |
| 2112 | lldb::addr_t addr = curr_piece_source_value.GetScalar().ULongLong( |
| 2113 | LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
| 2114 | error_ptr->SetErrorStringWithFormat( |
| 2115 | "failed to read memory DW_OP_piece(%" PRIu64"l" "u" |
| 2116 | ") from %s address 0x%" PRIx64"l" "x", |
| 2117 | piece_byte_size, curr_piece_source_value.GetValueType() == |
| 2118 | Value::ValueType::FileAddress |
| 2119 | ? "file" |
| 2120 | : "host", |
| 2121 | addr); |
| 2122 | } |
| 2123 | return false; |
| 2124 | |
| 2125 | case Value::ValueType::Scalar: { |
| 2126 | uint32_t bit_size = piece_byte_size * 8; |
| 2127 | uint32_t bit_offset = 0; |
| 2128 | Scalar &scalar = curr_piece_source_value.GetScalar(); |
| 2129 | if (!scalar.ExtractBitfield( |
| 2130 | bit_size, bit_offset)) { |
| 2131 | if (error_ptr) |
| 2132 | error_ptr->SetErrorStringWithFormat( |
| 2133 | "unable to extract %" PRIu64"l" "u" " bytes from a %" PRIu64"l" "u" |
| 2134 | " byte scalar value.", |
| 2135 | piece_byte_size, |
| 2136 | (uint64_t)curr_piece_source_value.GetScalar() |
| 2137 | .GetByteSize()); |
| 2138 | return false; |
| 2139 | } |
| 2140 | // Create curr_piece with bit_size. By default Scalar |
| 2141 | // grows to the nearest host integer type. |
| 2142 | llvm::APInt fail_value(1, 0, false); |
| 2143 | llvm::APInt ap_int = scalar.UInt128(fail_value); |
| 2144 | assert(ap_int.getBitWidth() >= bit_size)(static_cast <bool> (ap_int.getBitWidth() >= bit_size ) ? void (0) : __assert_fail ("ap_int.getBitWidth() >= bit_size" , "lldb/source/Expression/DWARFExpression.cpp", 2144, __extension__ __PRETTY_FUNCTION__)); |
| 2145 | llvm::ArrayRef<uint64_t> buf{ap_int.getRawData(), |
| 2146 | ap_int.getNumWords()}; |
| 2147 | curr_piece.GetScalar() = Scalar(llvm::APInt(bit_size, buf)); |
| 2148 | } break; |
| 2149 | } |
| 2150 | |
| 2151 | // Check if this is the first piece? |
| 2152 | if (op_piece_offset == 0) { |
| 2153 | // This is the first piece, we should push it back onto the stack |
| 2154 | // so subsequent pieces will be able to access this piece and add |
| 2155 | // to it. |
| 2156 | if (pieces.AppendDataToHostBuffer(curr_piece) == 0) { |
| 2157 | if (error_ptr) |
| 2158 | error_ptr->SetErrorString("failed to append piece data"); |
| 2159 | return false; |
| 2160 | } |
| 2161 | } else { |
| 2162 | // If this is the second or later piece there should be a value on |
| 2163 | // the stack. |
| 2164 | if (pieces.GetBuffer().GetByteSize() != op_piece_offset) { |
| 2165 | if (error_ptr) |
| 2166 | error_ptr->SetErrorStringWithFormat( |
| 2167 | "DW_OP_piece for offset %" PRIu64"l" "u" |
| 2168 | " but top of stack is of size %" PRIu64"l" "u", |
| 2169 | op_piece_offset, pieces.GetBuffer().GetByteSize()); |
| 2170 | return false; |
| 2171 | } |
| 2172 | |
| 2173 | if (pieces.AppendDataToHostBuffer(curr_piece) == 0) { |
| 2174 | if (error_ptr) |
| 2175 | error_ptr->SetErrorString("failed to append piece data"); |
| 2176 | return false; |
| 2177 | } |
| 2178 | } |
| 2179 | } |
| 2180 | op_piece_offset += piece_byte_size; |
| 2181 | } |
| 2182 | } break; |
| 2183 | |
| 2184 | case DW_OP_bit_piece: // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3); |
| 2185 | if (stack.size() < 1) { |
| 2186 | UpdateValueTypeFromLocationDescription(log, dwarf_cu, |
| 2187 | LocationDescriptionKind::Empty); |
| 2188 | // Reset for the next piece. |
| 2189 | dwarf4_location_description_kind = Memory; |
Value stored to 'dwarf4_location_description_kind' is never read | |
| 2190 | if (error_ptr) |
| 2191 | error_ptr->SetErrorString( |
| 2192 | "Expression stack needs at least 1 item for DW_OP_bit_piece."); |
| 2193 | return false; |
| 2194 | } else { |
| 2195 | UpdateValueTypeFromLocationDescription( |
| 2196 | log, dwarf_cu, dwarf4_location_description_kind, &stack.back()); |
| 2197 | // Reset for the next piece. |
| 2198 | dwarf4_location_description_kind = Memory; |
| 2199 | const uint64_t piece_bit_size = opcodes.GetULEB128(&offset); |
| 2200 | const uint64_t piece_bit_offset = opcodes.GetULEB128(&offset); |
| 2201 | switch (stack.back().GetValueType()) { |
| 2202 | case Value::ValueType::Invalid: |
| 2203 | return false; |
| 2204 | case Value::ValueType::Scalar: { |
| 2205 | if (!stack.back().GetScalar().ExtractBitfield(piece_bit_size, |
| 2206 | piece_bit_offset)) { |
| 2207 | if (error_ptr) |
| 2208 | error_ptr->SetErrorStringWithFormat( |
| 2209 | "unable to extract %" PRIu64"l" "u" " bit value with %" PRIu64"l" "u" |
| 2210 | " bit offset from a %" PRIu64"l" "u" " bit scalar value.", |
| 2211 | piece_bit_size, piece_bit_offset, |
| 2212 | (uint64_t)(stack.back().GetScalar().GetByteSize() * 8)); |
| 2213 | return false; |
| 2214 | } |
| 2215 | } break; |
| 2216 | |
| 2217 | case Value::ValueType::FileAddress: |
| 2218 | case Value::ValueType::LoadAddress: |
| 2219 | case Value::ValueType::HostAddress: |
| 2220 | if (error_ptr) { |
| 2221 | error_ptr->SetErrorStringWithFormat( |
| 2222 | "unable to extract DW_OP_bit_piece(bit_size = %" PRIu64"l" "u" |
| 2223 | ", bit_offset = %" PRIu64"l" "u" ") from an address value.", |
| 2224 | piece_bit_size, piece_bit_offset); |
| 2225 | } |
| 2226 | return false; |
| 2227 | } |
| 2228 | } |
| 2229 | break; |
| 2230 | |
| 2231 | // OPCODE: DW_OP_implicit_value |
| 2232 | // OPERANDS: 2 |
| 2233 | // ULEB128 size of the value block in bytes |
| 2234 | // uint8_t* block bytes encoding value in target's memory |
| 2235 | // representation |
| 2236 | // DESCRIPTION: Value is immediately stored in block in the debug info with |
| 2237 | // the memory representation of the target. |
| 2238 | case DW_OP_implicit_value: { |
| 2239 | dwarf4_location_description_kind = Implicit; |
| 2240 | |
| 2241 | const uint32_t len = opcodes.GetULEB128(&offset); |
| 2242 | const void *data = opcodes.GetData(&offset, len); |
| 2243 | |
| 2244 | if (!data) { |
| 2245 | LLDB_LOG(log, "Evaluate_DW_OP_implicit_value: could not be read data")do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Format("lldb/source/Expression/DWARFExpression.cpp" , __func__, "Evaluate_DW_OP_implicit_value: could not be read data" ); } while (0); |
| 2246 | 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); |
| 2247 | 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);; |
| 2248 | return false; |
| 2249 | } |
| 2250 | |
| 2251 | Value result(data, len); |
| 2252 | stack.push_back(result); |
| 2253 | break; |
| 2254 | } |
| 2255 | |
| 2256 | case DW_OP_implicit_pointer: { |
| 2257 | dwarf4_location_description_kind = Implicit; |
| 2258 | 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);; |
| 2259 | return false; |
| 2260 | } |
| 2261 | |
| 2262 | // OPCODE: DW_OP_push_object_address |
| 2263 | // OPERANDS: none |
| 2264 | // DESCRIPTION: Pushes the address of the object currently being |
| 2265 | // evaluated as part of evaluation of a user presented expression. This |
| 2266 | // object may correspond to an independent variable described by its own |
| 2267 | // DIE or it may be a component of an array, structure, or class whose |
| 2268 | // address has been dynamically determined by an earlier step during user |
| 2269 | // expression evaluation. |
| 2270 | case DW_OP_push_object_address: |
| 2271 | if (object_address_ptr) |
| 2272 | stack.push_back(*object_address_ptr); |
| 2273 | else { |
| 2274 | if (error_ptr) |
| 2275 | error_ptr->SetErrorString("DW_OP_push_object_address used without " |
| 2276 | "specifying an object address"); |
| 2277 | return false; |
| 2278 | } |
| 2279 | break; |
| 2280 | |
| 2281 | // OPCODE: DW_OP_call2 |
| 2282 | // OPERANDS: |
| 2283 | // uint16_t compile unit relative offset of a DIE |
| 2284 | // DESCRIPTION: Performs subroutine calls during evaluation |
| 2285 | // of a DWARF expression. The operand is the 2-byte unsigned offset of a |
| 2286 | // debugging information entry in the current compilation unit. |
| 2287 | // |
| 2288 | // Operand interpretation is exactly like that for DW_FORM_ref2. |
| 2289 | // |
| 2290 | // This operation transfers control of DWARF expression evaluation to the |
| 2291 | // DW_AT_location attribute of the referenced DIE. If there is no such |
| 2292 | // attribute, then there is no effect. Execution of the DWARF expression of |
| 2293 | // a DW_AT_location attribute may add to and/or remove from values on the |
| 2294 | // stack. Execution returns to the point following the call when the end of |
| 2295 | // the attribute is reached. Values on the stack at the time of the call |
| 2296 | // may be used as parameters by the called expression and values left on |
| 2297 | // the stack by the called expression may be used as return values by prior |
| 2298 | // agreement between the calling and called expressions. |
| 2299 | case DW_OP_call2: |
| 2300 | if (error_ptr) |
| 2301 | error_ptr->SetErrorString("Unimplemented opcode DW_OP_call2."); |
| 2302 | return false; |
| 2303 | // OPCODE: DW_OP_call4 |
| 2304 | // OPERANDS: 1 |
| 2305 | // uint32_t compile unit relative offset of a DIE |
| 2306 | // DESCRIPTION: Performs a subroutine call during evaluation of a DWARF |
| 2307 | // expression. For DW_OP_call4, the operand is a 4-byte unsigned offset of |
| 2308 | // a debugging information entry in the current compilation unit. |
| 2309 | // |
| 2310 | // Operand interpretation DW_OP_call4 is exactly like that for |
| 2311 | // DW_FORM_ref4. |
| 2312 | // |
| 2313 | // This operation transfers control of DWARF expression evaluation to the |
| 2314 | // DW_AT_location attribute of the referenced DIE. If there is no such |
| 2315 | // attribute, then there is no effect. Execution of the DWARF expression of |
| 2316 | // a DW_AT_location attribute may add to and/or remove from values on the |
| 2317 | // stack. Execution returns to the point following the call when the end of |
| 2318 | // the attribute is reached. Values on the stack at the time of the call |
| 2319 | // may be used as parameters by the called expression and values left on |
| 2320 | // the stack by the called expression may be used as return values by prior |
| 2321 | // agreement between the calling and called expressions. |
| 2322 | case DW_OP_call4: |
| 2323 | if (error_ptr) |
| 2324 | error_ptr->SetErrorString("Unimplemented opcode DW_OP_call4."); |
| 2325 | return false; |
| 2326 | |
| 2327 | // OPCODE: DW_OP_stack_value |
| 2328 | // OPERANDS: None |
| 2329 | // DESCRIPTION: Specifies that the object does not exist in memory but |
| 2330 | // rather is a constant value. The value from the top of the stack is the |
| 2331 | // value to be used. This is the actual object value and not the location. |
| 2332 | case DW_OP_stack_value: |
| 2333 | dwarf4_location_description_kind = Implicit; |
| 2334 | if (stack.empty()) { |
| 2335 | if (error_ptr) |
| 2336 | error_ptr->SetErrorString( |
| 2337 | "Expression stack needs at least 1 item for DW_OP_stack_value."); |
| 2338 | return false; |
| 2339 | } |
| 2340 | stack.back().SetValueType(Value::ValueType::Scalar); |
| 2341 | break; |
| 2342 | |
| 2343 | // OPCODE: DW_OP_convert |
| 2344 | // OPERANDS: 1 |
| 2345 | // A ULEB128 that is either a DIE offset of a |
| 2346 | // DW_TAG_base_type or 0 for the generic (pointer-sized) type. |
| 2347 | // |
| 2348 | // DESCRIPTION: Pop the top stack element, convert it to a |
| 2349 | // different type, and push the result. |
| 2350 | case DW_OP_convert: { |
| 2351 | if (stack.size() < 1) { |
| 2352 | if (error_ptr) |
| 2353 | error_ptr->SetErrorString( |
| 2354 | "Expression stack needs at least 1 item for DW_OP_convert."); |
| 2355 | return false; |
| 2356 | } |
| 2357 | const uint64_t die_offset = opcodes.GetULEB128(&offset); |
| 2358 | uint64_t bit_size; |
| 2359 | bool sign; |
| 2360 | if (die_offset == 0) { |
| 2361 | // The generic type has the size of an address on the target |
| 2362 | // machine and an unspecified signedness. Scalar has no |
| 2363 | // "unspecified signedness", so we use unsigned types. |
| 2364 | if (!module_sp) { |
| 2365 | if (error_ptr) |
| 2366 | error_ptr->SetErrorString("No module"); |
| 2367 | return false; |
| 2368 | } |
| 2369 | sign = false; |
| 2370 | bit_size = module_sp->GetArchitecture().GetAddressByteSize() * 8; |
| 2371 | if (!bit_size) { |
| 2372 | if (error_ptr) |
| 2373 | error_ptr->SetErrorString("unspecified architecture"); |
| 2374 | return false; |
| 2375 | } |
| 2376 | } else { |
| 2377 | // Retrieve the type DIE that the value is being converted to. This |
| 2378 | // offset is compile unit relative so we need to fix it up. |
| 2379 | const uint64_t abs_die_offset = die_offset + dwarf_cu->GetOffset(); |
| 2380 | // FIXME: the constness has annoying ripple effects. |
| 2381 | DWARFDIE die = const_cast<DWARFUnit *>(dwarf_cu)->GetDIE(abs_die_offset); |
| 2382 | if (!die) { |
| 2383 | if (error_ptr) |
| 2384 | error_ptr->SetErrorString("Cannot resolve DW_OP_convert type DIE"); |
| 2385 | return false; |
| 2386 | } |
| 2387 | uint64_t encoding = |
| 2388 | die.GetAttributeValueAsUnsigned(DW_AT_encoding, DW_ATE_hi_user); |
| 2389 | bit_size = die.GetAttributeValueAsUnsigned(DW_AT_byte_size, 0) * 8; |
| 2390 | if (!bit_size) |
| 2391 | bit_size = die.GetAttributeValueAsUnsigned(DW_AT_bit_size, 0); |
| 2392 | if (!bit_size) { |
| 2393 | if (error_ptr) |
| 2394 | error_ptr->SetErrorString("Unsupported type size in DW_OP_convert"); |
| 2395 | return false; |
| 2396 | } |
| 2397 | switch (encoding) { |
| 2398 | case DW_ATE_signed: |
| 2399 | case DW_ATE_signed_char: |
| 2400 | sign = true; |
| 2401 | break; |
| 2402 | case DW_ATE_unsigned: |
| 2403 | case DW_ATE_unsigned_char: |
| 2404 | sign = false; |
| 2405 | break; |
| 2406 | default: |
| 2407 | if (error_ptr) |
| 2408 | error_ptr->SetErrorString("Unsupported encoding in DW_OP_convert"); |
| 2409 | return false; |
| 2410 | } |
| 2411 | } |
| 2412 | Scalar &top = stack.back().ResolveValue(exe_ctx); |
| 2413 | top.TruncOrExtendTo(bit_size, sign); |
| 2414 | break; |
| 2415 | } |
| 2416 | |
| 2417 | // OPCODE: DW_OP_call_frame_cfa |
| 2418 | // OPERANDS: None |
| 2419 | // DESCRIPTION: Specifies a DWARF expression that pushes the value of |
| 2420 | // the canonical frame address consistent with the call frame information |
| 2421 | // located in .debug_frame (or in the FDEs of the eh_frame section). |
| 2422 | case DW_OP_call_frame_cfa: |
| 2423 | if (frame) { |
| 2424 | // Note that we don't have to parse FDEs because this DWARF expression |
| 2425 | // is commonly evaluated with a valid stack frame. |
| 2426 | StackID id = frame->GetStackID(); |
| 2427 | addr_t cfa = id.GetCallFrameAddress(); |
| 2428 | if (cfa != LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
| 2429 | stack.push_back(Scalar(cfa)); |
| 2430 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
| 2431 | } else if (error_ptr) |
| 2432 | error_ptr->SetErrorString("Stack frame does not include a canonical " |
| 2433 | "frame address for DW_OP_call_frame_cfa " |
| 2434 | "opcode."); |
| 2435 | } else { |
| 2436 | if (error_ptr) |
| 2437 | error_ptr->SetErrorString("Invalid stack frame in context for " |
| 2438 | "DW_OP_call_frame_cfa opcode."); |
| 2439 | return false; |
| 2440 | } |
| 2441 | break; |
| 2442 | |
| 2443 | // OPCODE: DW_OP_form_tls_address (or the old pre-DWARFv3 vendor extension |
| 2444 | // opcode, DW_OP_GNU_push_tls_address) |
| 2445 | // OPERANDS: none |
| 2446 | // DESCRIPTION: Pops a TLS offset from the stack, converts it to |
| 2447 | // an address in the current thread's thread-local storage block, and |
| 2448 | // pushes it on the stack. |
| 2449 | case DW_OP_form_tls_address: |
| 2450 | case DW_OP_GNU_push_tls_address: { |
| 2451 | if (stack.size() < 1) { |
| 2452 | if (error_ptr) { |
| 2453 | if (op == DW_OP_form_tls_address) |
| 2454 | error_ptr->SetErrorString( |
| 2455 | "DW_OP_form_tls_address needs an argument."); |
| 2456 | else |
| 2457 | error_ptr->SetErrorString( |
| 2458 | "DW_OP_GNU_push_tls_address needs an argument."); |
| 2459 | } |
| 2460 | return false; |
| 2461 | } |
| 2462 | |
| 2463 | if (!exe_ctx || !module_sp) { |
| 2464 | if (error_ptr) |
| 2465 | error_ptr->SetErrorString("No context to evaluate TLS within."); |
| 2466 | return false; |
| 2467 | } |
| 2468 | |
| 2469 | Thread *thread = exe_ctx->GetThreadPtr(); |
| 2470 | if (!thread) { |
| 2471 | if (error_ptr) |
| 2472 | error_ptr->SetErrorString("No thread to evaluate TLS within."); |
| 2473 | return false; |
| 2474 | } |
| 2475 | |
| 2476 | // Lookup the TLS block address for this thread and module. |
| 2477 | const addr_t tls_file_addr = |
| 2478 | stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS(18446744073709551615UL)); |
| 2479 | const addr_t tls_load_addr = |
| 2480 | thread->GetThreadLocalData(module_sp, tls_file_addr); |
| 2481 | |
| 2482 | if (tls_load_addr == LLDB_INVALID_ADDRESS(18446744073709551615UL)) { |
| 2483 | if (error_ptr) |
| 2484 | error_ptr->SetErrorString( |
| 2485 | "No TLS data currently exists for this thread."); |
| 2486 | return false; |
| 2487 | } |
| 2488 | |
| 2489 | stack.back().GetScalar() = tls_load_addr; |
| 2490 | stack.back().SetValueType(Value::ValueType::LoadAddress); |
| 2491 | } break; |
| 2492 | |
| 2493 | // OPCODE: DW_OP_addrx (DW_OP_GNU_addr_index is the legacy name.) |
| 2494 | // OPERANDS: 1 |
| 2495 | // ULEB128: index to the .debug_addr section |
| 2496 | // DESCRIPTION: Pushes an address to the stack from the .debug_addr |
| 2497 | // section with the base address specified by the DW_AT_addr_base attribute |
| 2498 | // and the 0 based index is the ULEB128 encoded index. |
| 2499 | case DW_OP_addrx: |
| 2500 | case DW_OP_GNU_addr_index: { |
| 2501 | if (!dwarf_cu) { |
| 2502 | if (error_ptr) |
| 2503 | error_ptr->SetErrorString("DW_OP_GNU_addr_index found without a " |
| 2504 | "compile unit being specified"); |
| 2505 | return false; |
| 2506 | } |
| 2507 | uint64_t index = opcodes.GetULEB128(&offset); |
| 2508 | lldb::addr_t value = dwarf_cu->ReadAddressFromDebugAddrSection(index); |
| 2509 | stack.push_back(Scalar(value)); |
| 2510 | stack.back().SetValueType(Value::ValueType::FileAddress); |
| 2511 | } break; |
| 2512 | |
| 2513 | // OPCODE: DW_OP_GNU_const_index |
| 2514 | // OPERANDS: 1 |
| 2515 | // ULEB128: index to the .debug_addr section |
| 2516 | // DESCRIPTION: Pushes an constant with the size of a machine address to |
| 2517 | // the stack from the .debug_addr section with the base address specified |
| 2518 | // by the DW_AT_addr_base attribute and the 0 based index is the ULEB128 |
| 2519 | // encoded index. |
| 2520 | case DW_OP_GNU_const_index: { |
| 2521 | if (!dwarf_cu) { |
| 2522 | if (error_ptr) |
| 2523 | error_ptr->SetErrorString("DW_OP_GNU_const_index found without a " |
| 2524 | "compile unit being specified"); |
| 2525 | return false; |
| 2526 | } |
| 2527 | uint64_t index = opcodes.GetULEB128(&offset); |
| 2528 | lldb::addr_t value = dwarf_cu->ReadAddressFromDebugAddrSection(index); |
| 2529 | stack.push_back(Scalar(value)); |
| 2530 | } break; |
| 2531 | |
| 2532 | case DW_OP_GNU_entry_value: |
| 2533 | case DW_OP_entry_value: { |
| 2534 | if (!Evaluate_DW_OP_entry_value(stack, exe_ctx, reg_ctx, opcodes, offset, |
| 2535 | error_ptr, log)) { |
| 2536 | 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); |
| 2537 | 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);; |
| 2538 | return false; |
| 2539 | } |
| 2540 | break; |
| 2541 | } |
| 2542 | |
| 2543 | default: |
| 2544 | if (error_ptr) |
| 2545 | error_ptr->SetErrorStringWithFormatv( |
| 2546 | "Unhandled opcode {0} in DWARFExpression", LocationAtom(op)); |
| 2547 | return false; |
| 2548 | } |
| 2549 | } |
| 2550 | |
| 2551 | if (stack.empty()) { |
| 2552 | // Nothing on the stack, check if we created a piece value from DW_OP_piece |
| 2553 | // or DW_OP_bit_piece opcodes |
| 2554 | if (pieces.GetBuffer().GetByteSize()) { |
| 2555 | result = pieces; |
| 2556 | return true; |
| 2557 | } |
| 2558 | if (error_ptr) |
| 2559 | error_ptr->SetErrorString("Stack empty after evaluation."); |
| 2560 | return false; |
| 2561 | } |
| 2562 | |
| 2563 | UpdateValueTypeFromLocationDescription( |
| 2564 | log, dwarf_cu, dwarf4_location_description_kind, &stack.back()); |
| 2565 | |
| 2566 | if (log && log->GetVerbose()) { |
| 2567 | size_t count = stack.size(); |
| 2568 | LLDB_LOGF(log,do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack after operation has %" "l" "u" " values:", (uint64_t)count); } while (0) |
| 2569 | "Stack after operation has %" PRIu64 " values:", (uint64_t)count)do { ::lldb_private::Log *log_private = (log); if (log_private ) log_private->Printf("Stack after operation has %" "l" "u" " values:", (uint64_t)count); } while (0); |
| 2570 | for (size_t i = 0; i < count; ++i) { |
| 2571 | StreamString new_value; |
| 2572 | new_value.Printf("[%" PRIu64"l" "u" "]", (uint64_t)i); |
| 2573 | stack[i].Dump(&new_value); |
| 2574 | 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); |
| 2575 | } |
| 2576 | } |
| 2577 | result = stack.back(); |
| 2578 | return true; // Return true on success |
| 2579 | } |
| 2580 | |
| 2581 | bool DWARFExpression::ParseDWARFLocationList( |
| 2582 | const DWARFUnit *dwarf_cu, const DataExtractor &data, |
| 2583 | DWARFExpressionList *location_list) { |
| 2584 | location_list->Clear(); |
| 2585 | std::unique_ptr<llvm::DWARFLocationTable> loctable_up = |
| 2586 | dwarf_cu->GetLocationTable(data); |
| 2587 | Log *log = GetLog(LLDBLog::Expressions); |
| 2588 | auto lookup_addr = |
| 2589 | [&](uint32_t index) -> llvm::Optional<llvm::object::SectionedAddress> { |
| 2590 | addr_t address = dwarf_cu->ReadAddressFromDebugAddrSection(index); |
| 2591 | if (address == LLDB_INVALID_ADDRESS(18446744073709551615UL)) |
| 2592 | return llvm::None; |
| 2593 | return llvm::object::SectionedAddress{address}; |
| 2594 | }; |
| 2595 | auto process_list = [&](llvm::Expected<llvm::DWARFLocationExpression> loc) { |
| 2596 | if (!loc) { |
| 2597 | LLDB_LOG_ERROR(log, loc.takeError(), "{0}")do { ::lldb_private::Log *log_private = (log); ::llvm::Error error_private = (loc.takeError()); if (log_private && error_private ) { log_private->FormatError(::std::move(error_private), "lldb/source/Expression/DWARFExpression.cpp" , __func__, "{0}"); } else ::llvm::consumeError(::std::move(error_private )); } while (0); |
| 2598 | return true; |
| 2599 | } |
| 2600 | auto buffer_sp = |
| 2601 | std::make_shared<DataBufferHeap>(loc->Expr.data(), loc->Expr.size()); |
| 2602 | DWARFExpression expr = DWARFExpression(DataExtractor( |
| 2603 | buffer_sp, data.GetByteOrder(), data.GetAddressByteSize())); |
| 2604 | location_list->AddExpression(loc->Range->LowPC, loc->Range->HighPC, expr); |
| 2605 | return true; |
| 2606 | }; |
| 2607 | llvm::Error error = loctable_up->visitAbsoluteLocationList( |
| 2608 | 0, llvm::object::SectionedAddress{dwarf_cu->GetBaseAddress()}, |
| 2609 | lookup_addr, process_list); |
| 2610 | location_list->Sort(); |
| 2611 | if (error) { |
| 2612 | LLDB_LOG_ERROR(log, std::move(error), "{0}")do { ::lldb_private::Log *log_private = (log); ::llvm::Error error_private = (std::move(error)); if (log_private && error_private ) { log_private->FormatError(::std::move(error_private), "lldb/source/Expression/DWARFExpression.cpp" , __func__, "{0}"); } else ::llvm::consumeError(::std::move(error_private )); } while (0); |
| 2613 | return false; |
| 2614 | } |
| 2615 | return true; |
| 2616 | } |
| 2617 | |
| 2618 | bool DWARFExpression::MatchesOperand( |
| 2619 | StackFrame &frame, const Instruction::Operand &operand) const { |
| 2620 | using namespace OperandMatchers; |
| 2621 | |
| 2622 | RegisterContextSP reg_ctx_sp = frame.GetRegisterContext(); |
| 2623 | if (!reg_ctx_sp) { |
| 2624 | return false; |
| 2625 | } |
| 2626 | |
| 2627 | DataExtractor opcodes(m_data); |
| 2628 | |
| 2629 | lldb::offset_t op_offset = 0; |
| 2630 | uint8_t opcode = opcodes.GetU8(&op_offset); |
| 2631 | |
| 2632 | if (opcode == DW_OP_fbreg) { |
| 2633 | int64_t offset = opcodes.GetSLEB128(&op_offset); |
| 2634 | |
| 2635 | DWARFExpressionList *fb_expr = frame.GetFrameBaseExpression(nullptr); |
| 2636 | if (!fb_expr) { |
| 2637 | return false; |
| 2638 | } |
| 2639 | |
| 2640 | auto recurse = [&frame, fb_expr](const Instruction::Operand &child) { |
| 2641 | return fb_expr->MatchesOperand(frame, child); |
| 2642 | }; |
| 2643 | |
| 2644 | if (!offset && |
| 2645 | MatchUnaryOp(MatchOpType(Instruction::Operand::Type::Dereference), |
| 2646 | recurse)(operand)) { |
| 2647 | return true; |
| 2648 | } |
| 2649 | |
| 2650 | return MatchUnaryOp( |
| 2651 | MatchOpType(Instruction::Operand::Type::Dereference), |
| 2652 | MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum), |
| 2653 | MatchImmOp(offset), recurse))(operand); |
| 2654 | } |
| 2655 | |
| 2656 | bool dereference = false; |
| 2657 | const RegisterInfo *reg = nullptr; |
| 2658 | int64_t offset = 0; |
| 2659 | |
| 2660 | if (opcode >= DW_OP_reg0 && opcode <= DW_OP_reg31) { |
| 2661 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, opcode - DW_OP_reg0); |
| 2662 | } else if (opcode >= DW_OP_breg0 && opcode <= DW_OP_breg31) { |
| 2663 | offset = opcodes.GetSLEB128(&op_offset); |
| 2664 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, opcode - DW_OP_breg0); |
| 2665 | } else if (opcode == DW_OP_regx) { |
| 2666 | uint32_t reg_num = static_cast<uint32_t>(opcodes.GetULEB128(&op_offset)); |
| 2667 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, reg_num); |
| 2668 | } else if (opcode == DW_OP_bregx) { |
| 2669 | uint32_t reg_num = static_cast<uint32_t>(opcodes.GetULEB128(&op_offset)); |
| 2670 | offset = opcodes.GetSLEB128(&op_offset); |
| 2671 | reg = reg_ctx_sp->GetRegisterInfo(m_reg_kind, reg_num); |
| 2672 | } else { |
| 2673 | return false; |
| 2674 | } |
| 2675 | |
| 2676 | if (!reg) { |
| 2677 | return false; |
| 2678 | } |
| 2679 | |
| 2680 | if (dereference) { |
| 2681 | if (!offset && |
| 2682 | MatchUnaryOp(MatchOpType(Instruction::Operand::Type::Dereference), |
| 2683 | MatchRegOp(*reg))(operand)) { |
| 2684 | return true; |
| 2685 | } |
| 2686 | |
| 2687 | return MatchUnaryOp( |
| 2688 | MatchOpType(Instruction::Operand::Type::Dereference), |
| 2689 | MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum), |
| 2690 | MatchRegOp(*reg), |
| 2691 | MatchImmOp(offset)))(operand); |
| 2692 | } else { |
| 2693 | return MatchRegOp(*reg)(operand); |
| 2694 | } |
| 2695 | } |